Showing papers in "Journal of Cellular Physiology in 2018"

Macrophage plasticity, polarization, and function in health and disease.

Abstract: Macrophages are heterogeneous and their phenotype and functions are regulated by the surrounding micro-environment. Macrophages commonly exist in two distinct subsets: 1) Classically activated or M1 macrophages, which are pro-inflammatory and polarized by lipopolysaccharide (LPS) either alone or in association with Th1 cytokines such as IFN-γ, GM-CSF, and produce pro-inflammatory cytokines such as interleukin-1β (IL-1β), IL-6, IL-12, IL-23, and TNF-α; and 2) Alternatively activated or M2 macrophages, which are anti-inflammatory and immunoregulatory and polarized by Th2 cytokines such as IL-4 and IL-13 and produce anti-inflammatory cytokines such as IL-10 and TGF-β. M1 and M2 macrophages have different functions and transcriptional profiles. They have unique abilities by destroying pathogens or repair the inflammation-associated injury. It is known that M1/M2 macrophage balance polarization governs the fate of an organ in inflammation or injury. When the infection or inflammation is severe enough to affect an organ, macrophages first exhibit the M1 phenotype to release TNF-α, IL-1β, IL-12, and IL-23 against the stimulus. But, if M1 phase continues, it can cause tissue damage. Therefore, M2 macrophages secrete high amounts of IL-10 and TGF-β to suppress the inflammation, contribute to tissue repair, remodeling, vasculogenesis, and retain homeostasis. In this review, we first discuss the basic biology of macrophages including origin, differentiation and activation, tissue distribution, plasticity and polarization, migration, antigen presentation capacity, cytokine and chemokine production, metabolism, and involvement of microRNAs in macrophage polarization and function. Secondly, we discuss the protective and pathogenic role of the macrophage subsets in normal and pathological pregnancy, anti-microbial defense, anti-tumor immunity, metabolic disease and obesity, asthma and allergy, atherosclerosis, fibrosis, wound healing, and autoimmunity.

NLRP3 inflammasome: Its regulation and involvement in atherosclerosis

Abstract: Inflammasomes are intracellular complexes involved in the innate immunity that convert proIL-1β and proIL-18 to mature forms and initiate pyroptosis via cleaving procaspase-1. The most well-known inflammasome is NLRP3. Several studies have indicated a decisive and important role of NLRP3 inflammasome, IL-1β, IL-18, and pyroptosis in atherosclerosis. Modern hypotheses introduce atherosclerosis as an inflammatory/lipid-based disease and NLRP3 inflammasome has been considered as a link between lipid metabolism and inflammation because crystalline cholesterol and oxidized low-density lipoprotein (oxLDL) (two abundant components in atherosclerotic plaques) activate NLRP3 inflammasome. In addition, oxidative stress, mitochondrial dysfunction, endoplasmic reticulum (ER) stress, and lysosome rupture, which are implicated in inflammasome activation, have been discussed as important events in atherosclerosis. In spite of these clues, some studies have reported that NLRP3 inflammasome has no significant effect in atherogenesis. Our review reveals that some molecules such as JNK-1 and ASK-1 (upstream regulators of inflammasome activation) can reduce atherosclerosis through inducing apoptosis in macrophages. Notably, NLRP3 inflammasome can also cause apoptosis in macrophages, suggesting that NLRP3 inflammasome may mediate JNK-induced apoptosis, and the apoptotic function of NLRP3 inflammasome may be a reason for the conflicting results reported. The present review shows that the role of NLRP3 in atherogenesis can be significant. Here, the molecular pathways of NLRP3 inflammasome activation and the implications of this activation in atherosclerosis are explained.

Interplay between miRNAs and human diseases

Abstract: MicroRNAs (miRNAs) are endogenous, non-coding RNAs, which have evoked a great deal of interest due to their importance in many aspects of homeostasis and diseases. MicroRNAs are stable and are essential components of gene regulatory networks. They play a crucial role in healthy individuals and their dysregulations have also been implicated in a wide range of diseases, including diabetes, cardiovascular disease, kidney disease, and cancer. This review summarized the current understanding of interactions between miRNAs and different diseases and their role in disease diagnosis and therapy.

The roles of signaling pathways in bone repair and regeneration.

Abstract: Regenerative medicine has sparked interest in potential strategies for bone repair. Bone defects are widespread and could be caused by trauma, congenital malformations, infections, and surgery. Although bone has a large self-healing capacity, some defects or fractures are too big to regenerate. To regenerate bone structures which can be used for treatment of patients, bone growth must be induced by a number of bioactive implantable materials, cell types and intracellular, and extracellular molecular signaling pathways. Since mesenchymal stem cells (MSCs) and their differentiation during remodeling processes have important roles in bone regeneration, it is believed that understanding molecular signaling pathways involved is crucial to the development of bone implants, bone substitute materials, and cell-based scaffolds for bone regeneration. In this review, we briefly introduce concepts in fracture repair and regeneration following bone injuries, and then discuss the current clinical methods in bone regeneration. In the next section, we review the involvement of the various key signaling pathways in bone regeneration.

Breast cancer diagnosis: Imaging techniques and biochemical markers.

Abstract: Breast cancer is a complex disease which is found as the second cause of cancer-associated death among women. Accumulating of evidence indicated that various factors (i.e., gentical and envirmental factors) could be associated with initiation and progression of breast cancer. Diagnosis of breast cancer patients in early stages is one of important aspects of breast cancer treatment. Among of various diagnosis platforms, imaging techniques are main diagnosis approaches which could provide valuable data on patients with breast cancer. It has been showed that various imaging techniques such as mammography, magnetic resonance imaging (MRI), positron-emission tomography (PET), Computed tomography (CT), and single-photon emission computed tomography (SPECT) could be used for diagnosis and monitoring patients with breast cancer in various stages. Beside, imaging techniques, utilization of biochemical biomarkers such as proteins, DNAs, mRNAs, and microRNAs could be employed as new diagnosis and therapeutic tools for patients with breast cancer. Here, we summarized various imaging techniques and biochemical biomarkers could be utilized as diagnosis of patients with breast cancer. Moreover, we highlighted microRNAs and exosomes as new diagnosis and therapeutic biomarkers for monitoring patients with breast cancer.

Treating cancer with microRNA replacement therapy: A literature review.

Abstract: microRNAs (miRNAs) are small non-coding RNAs that regulate gene expression post-transcriptionally by interfering with the translation of one or more target mRNAs. The unique miRNA sequences are involved in many physiological and pathological processes. Dysregulation of miRNAs contributes to the pathogenesis of all types of cancer. Notably, the diminished expression of tumor suppressor miRNAs, such as members of the Let-7 and miR-34 family, promotes tumor progression, invasion and metastasis. The past lustrum in particular, has witnessed substantial improvement of miRNA replacement therapy. This approach aims to restore tumor suppressor miRNA function in tumor cells using synthetic miRNA mimics or miRNA expression plasmids. Here, we provide a comprehensive review of recent advances in miRNA replacement therapy for treatment of cancer and its advantages over conventional gene therapy. We discuss a wide variety of delivery methods and vectors, as well as obstacles that remain to be overcome. Lastly, we review efforts to reverse epigenetic alterations, which affect miRNA expression in cancer cells, and the promising observation that restoring miRNA function re-sensitizes resistant tumor cells to chemotherapeutic drugs. The fact that various miRNA replacement therapies are currently in clinical trial demonstrates the great potential of this approach to treat cancer.

Probiotics are a good choice in remission of inflammatory bowel diseases: A meta analysis and systematic review.

Abstract: Altered gut bacteria and bacterial metabolic pathways are two important factors in initiation and progression of inflammatory bowel disease (IBD). However, efficacy of probiotics in remission of patients with IBD has not been characterized. This study was performed on the studies that specifically assessed the efficacy of probiotics in attaining clinical response on patients with various types of IBD. The efficacy of variant species of probiotics in different conditions and the influence of study quality in outcomes of randomized controlled trials (RCTs) were also assessed. The RCTs were collected by searching in MEDLINE Web of Science and Google scholar. Then all studies were abstracted in abstraction form and the outcomes were analyzed with fixed-effect and mixed-effect models for assessment of efficacy of variant species of probiotics in subgroups of IBDs. Analysis of 9 trials showed that probiotics had not significant effect on Crohn's disease (CD) (p = 0.07) but analysis of 3 trials in children with IBD revealed a significant advantage (p < 0.01). Analysis of 18 trials revealed that probiotics in patients with Ulcerative colitis (UC) in different conditions have significant effects (p = 0.007). VSL#3 probiotics in patients with UC had significant effect (p < 0.01). Combination of Lactobacillus probiotic, prebiotics had significant effect (p = 0.03) only in patients with UC. Combination of Saccharomyces boulardii, Lactobacillus, and VSL#3 probiotics in CD had also a trend for efficiency (p = 0.057). In children with IBD, the combination of Lactobacillus with VSL#3 probiotics had significant effect (p < 0.01). Probiotics are beneficial in IBD, especially the combination ones in UC.

Crosstalk of ER stress-mediated autophagy and ER-phagy: Involvement of UPR and the core autophagy machinery.

Abstract: Endoplasmic reticulum (ER) stress, a common cellular stress response, is closely related to the activation of autophagy that is an important and evolutionarily conserved mechanism for maintaining cellular homeostasis. Autophagy induced by ER stress mainly includes the ER stress-mediated autophagy and ER-phagy. The ER stress-mediated autophagy is characterized by the generation of autophagosomes that include worn-out proteins, protein aggregates, and damaged organelles. While the autophagosomes of ER-phagy selectively include ER membranes, and the double membranes also derive, at least in part, from the ER. The signaling pathways of IRE1α, PERK, ATF6, and Ca2+ are necessary for the activation of ER stress-mediated autophagy, while the receptor-mediated selective ER-phagy degrades the ER is Atg40/FAM134B. The ER stress-mediated autophagy and ER-phagy not only have differences, but also have connections. The activation of ER-phagy requires the core autophagy machinery, and the ER-phagy may be a branch of ER stress-mediated autophagy that selectively targets the ER. However, the determined factors that control the changeover switch between ER stress-mediated autophagy and ER-phagy are largely obscure, which may be associated with the type of cells and the extent of stimulation. This review summarized the crosstalk between ER stress-mediated autophagy and ER-phagy and their signaling networks. Additionally, we discussed the possible factors that influence the type of autophagy induced by ER stress.

Therapeutic effects of curcumin in inflammatory and immune-mediated diseases: A nature-made jack-of-all-trades?

Abstract: Curcumin is a dietary polyphenol from turmeric with numerous pharmacological activities. Novel animal and human studies indicate that curcumin can affect different immune cells, such as various T lymphocyte subsets, macrophages, dendritic cells, B lymphocytes and natural killer cells, which results in decreasing severity of various diseases with immunological etiology. The present review provides a comprehensive overview of the effects of curcumin on different immune cells and immune system-related diseases.

The prognostic value of MGMT promoter methylation in glioblastoma: A meta-analysis of clinical trials

Abstract: The DNA repair protein O6-Methylguanine-DNA methyltransferase (MGMT) is suggested to be associated with resistance to alkylating agents such as Temozolomide which is being used in treatment of patients with glioblastoma (GBM). Therefore, we evaluated the associations between MGMT promoter methylation and prognosis of patients with glioblastoma (GBM). Data were extracted from publications in Embase, PubMed, and the Cochrane Library. Data on overall survival (OS), progression-free survival (PFS), and MGMT methylation status were obtained and 4,097 subjects were enrolled. Data from 34 studies showed that MGMT methylated patients had better OS, compared to GBM unmethylated patients (pooled HRs, 0.494; 95%CI 0.412-0.591; p = 0.001). Meta-analysis of 10 eligible studies reporting on PFS, demonstrated that MGMT promoter methylation was not significantly associated with better PFS (pooled HRs, 0.653; 95%CI 0.414-1.030; p = 0.067). GBM patients with MGMT methylation were associated with longer overall survival, although this effect was not detected for PFS. Moreover, we performed further analysis in patients underwent a comprehensive imaging evaluation. This data showed a significant association with better OS and PFS, although further studies are warranted to assess the value of emerging marker in prospective setting in patients with glioblastoma as a risk stratification biomarker in clinical management of the patients.

MicroRNA: A novel target of curcumin in cancer therapy.

Abstract: Curcumin is known as a natural dietary polyphenol which is extracted from Curcuma longa L. It has been shown that curcumin has a variety of pharmacological effects such as antioxidant, anti-cancer, anti-inflammatory, and anti-microbial activities. Anti-cancer effects of curcumin are due to targeting of a wide range of cellular and molecular pathways involved in cancer pathogenesis including NF-kB, MAPK, PTEN, P53, and microRNAs (miRNA) network. Multiple lines of evidence have indicated that curcumin exerts its therapeutic effects via regulating miRNA expression (e.g., miR-1, miR-7, miR-9, miR-34a, miR-181, miR-21, and miR-19) which could lead to the regulation of underlying cellular and molecular pathways involved in cancer pathogenesis. Exosomes are one of the important classes of biological vehicles which could be released from various types of cells such as cancer cells and stem cells and could change the behavior of recipient cells. It has been shown that treatment of cancer cells with different dose of curcumin leads to the release of exosomes containing curcumin. These exosomes could induce anti-cancer properties in recipient cells and reduce tumor growth. Hence, exosomes containing curcumin could be applied as powerful tools for cancer treatment. Here, we highlighted various miRNAs which could be affected by curcumin in various types of cancer. Moreover, we highlight exosomes containing curcumin as suitable therapeutic tools in cancer therapy.

Curcumin as a potential candidate for treating hyperlipidemia: A review of cellular and metabolic mechanisms.

Abstract: Curcumin is an herbal polyphenol extensively investigated for antioxidant, anti-inflammatory, and hypolipidaemic properties. In the present review, the efficacy of curcumin for improving a plasma lipid profile has been evaluated and compared with statins, a well-known class of medicines for treating hypercholesterolemia and hyperlipidaemia. Curcumin is presumably most effective in reducing triglyceride (TG), while statins are most efficient in lowering low-density lipoproteins-cholesterol (LDL-C). Additionally, various molecular and metabolic mediators of cholesterol and plasma lipid homeostasis are discussed in relation to how they are modulated by curcumin or statins. Overall, curcumin influences the same mediators of plasma lipid alteration as statins do. Almost all the pathways through which cholesterol trafficking takes place are affected by these agents. These include gastrointestinal absorption of dietary cholesterol, hepatocellular removal of plasma cholesterol, the mediators of reverse cholesterol transport, and removal of cholesterol from peripheral tissues. Moreover, the reactive oxygen species (ROS) scavenging potential of curcumin limits the risk of lipid peroxidation that triggers inflammatory responses causing cardiovascular diseases (CVD) and atherosclerosis. Taken together, curcumin could be used as a safe and well-tolerated adjunct to statins to control hyperlipidaemia more effectively than statins alone.

Inflammasome: its role in traumatic brain and spinal cord injury†

Abstract: Traumatic brain injury (TBI) and spinal cord injury (SCI) are pathological events that lead to neuropathological conditions which have in consequence the initiation of pro-inflammatory cytokine production. Neuroinflammation plays a key role in the secondary phase of both TBI and SCI after initial cell death. Activation of cytoplasmic inflammasome complexes is regarded as the essential step of neuroinflammation and a key trigger for neuronal death called pyroptosis. Inflammasome complexes are involved in activation of caspase-1 which catalyzes the cleavage of pro-interleukins into their active forms (including interleukin-18 [IL-18] and IL-1β). The focus of this article is to discuss the time-course and regulation of inflammasome assembly and activation during TBI and SCI and their targeting in designing therapeutic approaches. We particularly focus on the inflammasomes NLRP1 and NLRP3 which play a pivotal function during TBI and SCI in the central nervous system (CNS).

Adipocytes properties and crosstalk with immune system in obesity‐related inflammation

Abstract: Obesity is a condition likely associated with several dysmetabolic conditions or worsening of cardiovascular and other chronic disturbances. A key role in this mechanism seem to be played by the onset of low-grade systemic inflammation, highlighting the importance of the interplay between adipocytes and immune system cells. Adipocytes express a complex and highly adaptive biological profile being capable to selectively activate different metabolic pathways in order to respond to environmental stimuli. It has been demonstrated how adipocytes, under appropriate stimulation, can easily differentiate and de-differentiate thereby converting themselves into different phenotypes according to metabolic necessities. Although underlying mechanisms are not fully understood, growing in adipocyte size and the inability of storing triglycerides under overfeeding conditions seem to be crucial for the switching to a dysfunctional metabolic profile, which is characterized by inflammatory and apoptotic pathways activation, and by the shifting to pro-inflammatory adipokines secretion. In obesity, changes in adipokines secretion along with adipocyte deregulation and fatty acids release into circulation contribute to maintain immune cells activation as well as their infiltration into regulatory organs. Over the well-established role of macrophages, recent findings suggest the involvement of new classes of immune cells such as T regulatory lymphocytes and neutrophils in the development inflammation and multi systemic worsening. Deeply understanding the pathways of adipocyte regulation and the de-differentiation process could be extremely useful for developing novel strategies aimed at curbing obesity-related inflammation and related metabolic disorders.

MicroRNAs: Potential candidates for diagnosis and treatment of colorectal cancer.

Abstract: Colorectal cancer (CRC) is known as the third common cancer worldwide and an important public health problem in different populations. Several genetics and environmental risk factors are involved in the development and progression of CRC including chromosomal abnormalities, epigenetic alterations, and unhealthy lifestyle. Identification of risk factors and biomarkers could lead to a better understanding of molecular pathways involved in CRC pathogenesis. MicroRNAs (miRNAs) are important regulatory molecules which could affect a variety of cellular and molecular targets in CRC. A large number of studies have indicated deregulations of some known tissue-specific miRNAs, for example, miR-21, miR-9, miR-155, miR-17, miR-19, let-7, and miR-24 as well as circulating miRNAs, for example, miR-181b, miR-21, miR-183, let-7g, miR-17, and miR-126, in patients with CRC. In the current review, we focus on the findings of preclinical and clinical studies performed on tissue-specific and circulating miRNAs as diagnostic biomarkers and therapeutic targets for the detection of patients at various stages of CRC.

Ferritinophagy/ferroptosis: Iron‐related newcomers in human diseases

Abstract: Nuclear receptor coactivator 4 mediated ferritinophagy is an autophagic phenomenon that specifically involves ferritin to release intracellular free iron. Ferritinophagy is implicated in maintaining efficient erythropoiesis. Notably, ferritinophagy also plays a central role in driving some pathological processes, including Parkinson's disease (PD) and urinary tract infections. Some evidence has demonstrated that ferritinophagy is critical to induce ferroptosis. Ferroptosis is a newly nonapoptotic form of cell death, characterized by the accumulation of iron-based lipid reactive oxygen species. Ferroptosis plays an important role in inhibiting some types of cancers, such as hepatocellular carcinoma, pancreatic carcinoma, prostate cancer, and breast cancer. Conversely, the activation of ferroptosis accelerates neurodegeneration diseases, including PD and Alzheimer's disease. Therefore, in this review, we summarize the regulatory mechanisms related to ferritinophagy and ferroptosis. Moreover, the distinctive effects of ferritinophagy in human erythropoiesis and some pathologies, coupled with the promotive or inhibitory role of tumorous and neurodegenerative diseases mediated by ferroptosis, are elucidated. Obviously, activating or inhibiting ferroptosis could be exploited to achieve desirable therapeutic effects on diverse cancers and neurodegeneration diseases. Interrupting ferritinophagy to control iron level might provide a potentially therapeutic avenue to suppress urinary tract infections.

Exosomal miRNAs as novel cancer biomarkers: Challenges and opportunities

Abstract: A biomarker with high specificity and sensitivity, is a basic requirement for non-invasive cancer diagnosis. Exosomes are a type of lipid bilayer extracellular vesicles (EVs), containing different components, including proteins, lipids, DNA, messenger RNA (mRNA), and non-coding RNAs. Increasing evidence indicates that nucleic acids are protected by exosome lipid membrane. These vesicles are almost released from all cell types, into biological fluids. In cancer, the expression of microRNAs (miRNAs), located in the tumor cell-derived exosomes, is deregulated and it could be led to metastasis and therapy resistance. Due to the presence of exosomes in various body fluids and the stability of miRNAs in exosomes, exosomal miRNAs can provide a new class of biomarkers for early and minimally invasive cancer diagnosis. In this article, we review the miRNAs and their roles in cancer. Furthermore, we explain the different types of EVs, especially exosomes, and their functional roles in cancer. At the end, we discuss about the importance of exosomal miRNAs for cancer diagnosis. As well as, we briefly summarize the exosome isolation techniques and obstacles, limiting the clinical applications of exosomal miRNAs.

MicroRNA: Relevance to stroke diagnosis, prognosis, and therapy

Abstract: Stroke is a life-threatening disease that accounts for a considerable burden of mortality in both developing and developed world. Identification of specific biomarkers for stroke and its outcomes can greatly contribute to improved care of patients. MicroRNAs (miRNAs) are known as novel biomarkers that could be used as diagnostic, prognostic, and therapeutic biomarkers. Various studies have shown that miRNAs have key roles in the pathogenesis of stroke, and its complications and outcomes. In addition, there is evidence showing that mesenchaymal stromal cell-derived exosomes containing miRNAs can be used for monitoring and treatment of various diseases such as stroke. Here, we summarized various aspects of miRNA applications in different stages of stroke.

Three-dimensional cell culture models for anticancer drug screening: Worth the effort?

Abstract: High attrition of new oncology drug candidates in clinical trials is partially caused by the poor predictive capacity of artificial monolayer cell culture assays early in drug discovery. Monolayer assays do not take the natural three-dimensional (3D) microenvironment of cells into account. As a result, false positive compounds often enter clinical trials, leading to high dropout rates and a waste of time and money. Over the past 2 decades, tissue engineers and cell biologists have developed a broad range of 3D in vitro culturing tools that better represent in vivo cell biology. These tools preserve the 3D architecture of cells and can be used to predict toxicity of and resistance against antitumor agents. Recent progress in tissue engineering further improves 3D models by taking into account the tumor microenvironment, which is important for metastatic progression and vascularization. However, the widespread implementation of 3D cell cultures into cell-based research programs has been limited by various factors, including their cost and reproducibility. In addition, different 3D cell culture techniques often produce spheroids of different size and shape, which can strongly influence drug efficacy and toxicity. Hence, it is imperative to morphometrically characterize multicellular spheroids to avoid generalizations among different spheroid types. Standardized 3D culturing procedures could further reduce data variability and enhance biological relevance. Here, we critically evaluate the benefits and challenges inherent to growing cells in 3D, along with an overview of the techniques used to form spheroids. This is done with a specific focus on antitumor drug screening.

Monocyte-to-HDL-cholesterol ratio as a prognostic marker in cardiovascular diseases.

Abstract: Inflammation and lipid accumulation are two basic hallmarks of atherosclerosis as a chronic disease. Inflammation not only is a local response but can also be considered as a systemic process followed by an elevation of inflammatory mediators. Monocytes are a major source of proinflammatory species during atherogenesis. In atherosclerosis, modified low-density lipoproteins (LDLs) are removed by macrophages; these are recruited in the vessel wall, inducing the release of inflammatory cytokines in inflamed tissue. Hence, inflammatory cholesterol ester-loaded plaque is generated. High-density lipoprotein-cholesterol (HDL-C) exhibits antiatherosclerotic effects by neutralizing the proinflammatory and pro-oxidant effects of monocytes via inhibiting the migration of macrophages and LDL oxidation in addition to the efflux of cholesterol from these cells. Furthermore, HDL plays a role in suppressing the activation of monocytes and proliferation-differentiation of monocyte progenitor cells. Thus, accumulation of monocytes and reduction of HDL-C may participate in atherosclerosis and cardiovascular diseases (CVD). Given that the relationship between the high number of monocytes and low HDL-C levels has been reported in inflammatory disorders, this review focused on understanding whether the monocyte-to-HDL ratio could be a convenient marker to predict atherosclerosis development and progression, hallmarks of CV events, instead of the individual monocyte count or HDL-C level.

miRNAs and ovarian cancer: An overview†

Abstract: Ovarian cancer (OC) is the sixth most common cancer in women globally. However, even with the advances in detection andtherapeutics it still represents the most dangerous gynecologic malignancy in women of the industrialized countries. The discovery of micro- RNAs (miRNA), a small noncoding RNA molecule targeting multiple mRNAs and regulation of gene expression by triggering translation repression and/or RNA degradation, has revealed the existence of a new array for regulation of genes involved in cancer. This review summarizes the current knowledge regarding the role of miRNAs expression in OC. It also provides information about potential clinical relevance of circulating miRNAs for OC diagnosis, prognosis, and therapeutics. The identification of functional targets for miRNAs represents a major obstacle in our understanding of microRNA function in OC, but significant progress is being made. The better understanding of the role of microRNA expression in ovarian cancer may provide new array for the detection, diagnosis, and therapy of the OC. This article is protected by copyright. All rights reserved

Modulating tumor hypoxia by nanomedicine for effective cancer therapy.

Abstract: Hypoxia, a characteristic feature of tumors, is indispensable to tumor angiogenesis, metastasis, and multi drug resistance. Hypoxic avascular regions, deeply embedded inside the tumors significantly hinder delivery of therapeutic agents. The low oxygen tension results in resistance to the current applied anti-cancer therapeutics including radiotherapy, chemotherapy, and photodynamic therapy, the efficacy of which is firmly tied to the level of tumor oxygen supply. However, emerging data indicate that nanocarriers/nanodrugs can offer substantial benefits to improve the efficacy of current therapeutics, through modulation of tumor hypoxia. This review aims to introduce the most recent advances made in nanocarrier mediated targeting of tumor hypoxia. The first part is dedicated to the approaches by which nanocarriers could be designed to target/leverage hypoxia. These approaches include i) inhibiting Hypoxia Inducer Factor (HIF-1α); ii) hypoxia activated prodrugs/linkers; and iii) obligate anaerobe mediated targeting of tumor hypoxia. The second part, details novel nanosystems proposed to modulate tumor hypoxia through tumor oxygenation. These methods seek to lessen tumor hypoxia through vascular normalization, or reoxygenation therapy. The reoxygenation of tumor could be accomplished by: i) generation of oxygen filled nanocarriers; ii) natural/artificial oxygen nanocarriers; and iii) oxygen generators. The efficacy of each approach and their potential in cancer therapy is further discussed.

Myeloid-derived suppressor cells: Important contributors to tumor progression and metastasis.

Abstract: Myeloid-derived suppressor cells (MDSCs) are traditionally considered among the major components of the immunosuppressive tumor microenvironment (TME). However, there is currently increasing evidence indicating that MDSCs in addition to suppression of immune surveillance is also involved in an array of non-immunological functions like augmenting metastatic potential of tumor cells. Indeed, MDSCs can promote metastasis in animal models and cancer patients through promoting premetastatic niche formation, tumor angiogenesis and invasion. Moreover, MDSC frequency and function have been associated with progressive disease and correlated with clinical outcome. This review will summarize and discusses the data demonstrating the role for MDSCs in tumor metastasis.

LncRNA MALAT1 induces colon cancer development by regulating miR-129-5p/HMGB1 axis

Abstract: Recent studies have exhibited significant roles of lncRNAs in various tumors' development, including colon cancer. Our study focused on the biological roles of lncRNA MALAT1 in colon cancer. In our study, it was demonstrated that MALAT1 was upregulated in human colon cancer cell lines including Lovo, HCT116, SW480 and HT29 cells compared to the normal human intestinal epithelial HIEC cells. Moreover, we observed that miR-129-5p was downregulated in colon cancer cells with a significant increase of HMGB1 expression. Inhibition of MALAT1 can inhibit the proliferation of colon cancer SW480 and HCT116 cells and next, bioinformatics analysis was used to predict the target microRNA of MALAT1. miR-129-5p was identified and confirmed as a direct regulator of MALAT1 and it was shown that miR-129-5p mimics were able to restrain the progression of colon cancer cells. In addition, high motility group box protein 1 (HMGB1), was predicted as a mRNA target of miR-129-5p. Furthermore, we found that MALAT1 exerted its biological functions through regulating HMGB1 by sponging miR-129-5p in vitro. Silencing MALAT1 greatly inhibited HMGB1 expression which can be reversed by miR-129-5p inhibitors. It was indicated in our investigation that MALAT1 may serve as a competing endogenous lncRNA (ceRNA) to mediate HMGB1 by sponging miR-129-5p in colon cancer. Taken together, our results indicated that MALAT1/miR-129-5p/HMGB1 axis could be provided as an important prognostic biomarker in colon cancer development. This article is protected by copyright. All rights reserved

Emerging roles of ER stress and unfolded protein response pathways in skeletal muscle health and disease

Abstract: Skeletal muscle is the most abundant tissue in the human body and can adapt its mass as a consequence of physical activity, metabolism, growth factors, and disease conditions. Skeletal muscle contains an extensive network of endoplasmic reticulum (ER), called sarcoplasmic reticulum, which plays an important role in the regulation of proteostasis and calcium homeostasis. In many cell types, environmental and genetic factors that disrupt ER function cause an accumulation of misfolded and unfolded proteins in the ER lumen that ultimately leads to ER stress. To alleviate the stress and restore homeostasis, the ER activates a signaling network called the unfolded protein response (UPR). The UPR has three arms, which regulate protein synthesis and expression of many ER chaperone and regulatory proteins. However, the role of individual UPR pathways in skeletal muscle has just begun to be investigated. Recent studies suggest that UPR pathways play pivotal roles in muscle stem cell homeostasis, myogenic differentiation, and regeneration of injured skeletal muscle. Moreover, markers of ER stress and the UPR are activated in skeletal muscle in diverse conditions such as exercise, denervation, starvation, high fat diet, cancer cachexia, and aging. Accumulating evidence also suggests that ER stress may have important roles in the pathogenesis of inflammatory myopathies and genetic muscle disorders. The purpose of this review article is to discuss the role and potential mechanisms by which ER stress and the individual arms of the UPR regulate skeletal muscle formation, plasticity, and function in various physiological and pathophysiological conditions.

Nanoparticles as new tools for inhibition of cancer angiogenesis.

Abstract: Angiogenesis is known as one of the hallmarks of cancer. Multiple lines evidence indicated that vascular endothelium growth factor (VEGF) is a key player in the progression of angiogenesis and exerts its functions via interaction with tyrosine kinase receptors (TKRs). These receptors could trigger a variety of cascades that lead to the supply of oxygen and nutrients to tumor cells and survival of these cells. With respect to pivotal role of angiogenesis in the tumor growth and survival, finding new therapeutic approaches via targeting angiogenesis could open a new horizon in cancer therapy. Among various types of therapeutic strategies, nanotechnology has emerged as new approach for the treatment of various cancers. Nanoparticles (NPs) could be used as effective tools for targeting a variety of therapeutic agents. According to in vitro and in vivo studies, NPs are efficient in depriving tumor cells from nutrients and oxygen by inhibiting angiogenesis. However, the utilization of NPs are associated with a variety of limitations. It seems that new approaches such as NPs conjugated with hydrogels could overcome to some limitations. In the present review, we summarize various mechanisms involved in angiogenesis, common anti-angiogenesis strategies, and application of NPs for targeting angiogenesis in various cancers.

The prognostic and therapeutic application of microRNAs in breast cancer: Tissue and circulating microRNAs

Abstract: Breast cancer is the second most common malignancy diagnosed in women, supporting the need for identification of novel prognostic and diagnostic biomarkers. Recently, microRNAs have emerged as molecular regulators that can have key roles in pathogenesis and progression of different malignancies, including breast cancer. Micro-RNAs can be circulated in body fluid, suggesting their values as non-invasive marker. There is growing body of evidence showing the aberrant activation of some known circulating miRNAs, for example let-151a, miR-21, miR-155, miR-,145 miR-18a, miR-16 as well as tissue specific-miRNAs, for example miR-182, miR-145, miR-21, miR-155/154, miR-203, miR-213, miR-7 in patients affected by breast cancer. In addition, there is growing body of evidences on the value of miRNAs to be associated with drug-resistance, suggesting their values as a potential approach to overcome chemo-resistance. Attuned with these facts, this review highlights recent preclinical and clinical investigation performed on tissue-specific miRNAs and circulating as novel promising biomarkers for detection of patients at early stages, prediction of prognosis, and monitoring of the patients in response to therapy.

The lncRNA MALAT1 contributes to non-small cell lung cancer development via modulating miR-124/STAT3 axis.

Abstract: lncRNAs can exert many biological effects in several cancer types. MALAT1 is a kind of lncRNA which is greatly overexpressed in several tumors including non-small cell lung cancer (NSCLC). However, the mechanism of MALAT1 in NSCLC still remains unclear. In our current study, we concentrated on the biological mechanism of MALAT1 in NSCLC. It was observed that MALAT1 was significantly upregulated in five human NSCLC cells including A549, H23, H522, H1299, and H460 cells compared to normal bronchial epithelial cell line 16HBE cells. On the contrary, miR-124 was remarkably downregulated, which indicated a potential negative correlation between miR-124 and MALAT1. MALAT1 inhibition can increase miR-124 expression in A549 and H460 cells. In addition, miR-124 mimics were able to repress MALAT1 expression and miR124 inhibitors can promote MALAT1 levels. Then it was found that shMALAT1 can inhibit NSCLC cell proliferation, colony formation and apoptosis, which can be reversed by miR-124 inhibitors. Bioinformatic analysis predicted the correlation between miR-124 and MALAT1. In addition, STAT3 was found to be a novel mRNA target of miR-124. Downregulation of MALAT1 can inhibit NSCLC development by enhancing miR-124 and decreasing STAT3 expression. We speculated that MALAT1can act as a competing endogenous lncRNA (ceRNA) to modulate miR-124/STAT3 in NSCLC. Taken these together, we revealed that MALAT1/miR-124/STAT3 was involved in NSCLC development.

Molecular mechanisms of drug resistance in ovarian cancer.

Abstract: Ovarian cancer is the most lethal malignancy among the gynecological cancers, with a 5-year survival rate, mainly due to being diagnosed at advanced stages, recurrence and resistance to the current chemotherapeutic agents. Drug resistance is a complex phenomenon and the number of known involved genes and cross-talks between signaling pathways in this process is growing rapidly. Thus, discovering and understanding the underlying molecular mechanisms involved in chemo-resistance are crucial for management of treatment and identifying novel and effective drug targets as well as drug discovery to improve therapeutic outcomes. In this review, the major and recently identified molecular mechanisms of drug resistance in ovarian cancer from relevant literature have been investigated. In the final section of the paper, new approaches for studying detailed mechanisms of chemo-resistance have been briefly discussed.

Circulating microRNAs as diagnostic and therapeutic biomarkers in gastric and esophageal cancers

Abstract: Gastric and esophageal cancers are as main cancers of the gastrointestinal (GI) tract, which are associated with poor diagnosis and survival. Several efforts were made in the past few decades to finding effective therapeutic approaches, but these approaches had several problems. Finding new biomarkers is a critical step in finding new approaches for the treatment of these cancers. Finding new biomarkers that cover various aspects of the diseases could provide a choice of suitable therapies and better monitoring of patients with these cancers. Among several biomarkers tissue specific and circulating microRNAs (miRNAs) have emerged as powerful candidates in the diagnosis of gastric and esophageal cancers. MiRNAs are small noncoding single-stranded RNA molecules that are found in the blood and regulate gene expression. These have numerous characteristics that make them suitable for being used as ideal biomarkers in cancer diagnosis. Research has indicated that the level and profile of miRNA in serum and plasma are very high. They are potentially noninvasive and sensitive enough to detect tumors in their primary stages of infection. Multiple lines of evidence indicate that the presence, absence, or deregulation of several circulating miRNAs (i.e., let-7a, miR-21, miR-93, miR-192a, miR-18a, and miR-10b for gastric cancer, and miR-21, miR-375, miR-25-3p, miR-151a-3p, and miR-100-3p for esophageal cancer) are associated with initiation and progression of gastric and esophageal cancers. The aim of this review is to highlight the recent advances in the roles of miRNAs in diagnosis and treatment of gastric and esophageal cancers.