Lei Shen

Bio: Lei Shen is an academic researcher from Nantong University. The author has contributed to research in topics: CA15-3 & Akt/PKB signaling pathway. The author has an hindex of 4, co-authored 5 publications receiving 47 citations.

Diagnostic Value of Serum Concentration and Integrity of Circulating Cell-Free DNA in Breast Cancer: A Comparative Study With CEA and CA15-3.

Abstract: Breast cancer (BC) is one of the most common types of malignant neoplasm in women; the incidence of BC increases yearly. In a previous study, a novel and sensitive method for quantitying cell-free DNA (CFD) in human blood was established and tested for its ability to predict which patients harbored tumors. Our objective in this study was to investigate the clinical value of serum concentration and the integrity of circulating free DNA (CFD) as a biomarker for auxiliary diagnosis of BC. The concentration of CFD was quantitated by branched DNA (bDNA)-based Alu assay. Carcinoembryonic antigen (CEA) and cancer antigen 15-3 (CA 15-3) concentrations were determined via Abbott ARCHITECT I2000 SR testing. We report that the median (quartile interval) values of serum ALU115 and ALU247/115 in patients with BC were significantly higher than those in patients with benign mammary hyperplasia and in healthy control individuals (1083.66 ng/mL [1.81] vs 145.87 ng/mL [0.33] and 228.19 ng/mL [0.48]; P .05). The cutoff values of ALU115, ALU247/115, CEA, and CA15-3 were set as 300.96 ng per mL, 0.78, 5 ng per mL, and 31.3 ng per mL, respectively. The area under the receiver operating characteristic (ROC) curve was 0.70 (95% confidence interval [CI], 0.58-0.81), 0.97 ( .99), 0.75 (0.65-0.86), and 0.89 (0.82-0.96), respectively. Combined detection of the 4 indices significantly improved the diagnostic accuracy of BC, with sensitivity of 97.5% and negative predictive value of 96.4%. Also, serum ALU115 was significantly correlated with lymph-node metastasis (P = .048), and the ALU247/115 index was significantly correlated with tumor stage (P = .001) and lymph-node metastasis (P = .008) in patients with BC. Serum cell-free DNA (CFD) and its integrity may prove to be useful biomarkers for auxiliary diagnosis, grading of malignant neoplasms, and prognostic prediction of BC.

As a biomarker for gastric cancer, circPTPN22 regulates the progression of gastric cancer through the EMT pathway.

Abstract: Gastric cancer (GC) is one of the most common cancers in the world. Due to the lack of specific symptoms, more than 80% of patients are diagnosed as the advanced stage with a high mortality rate, so the early diagnosis of GC is incredibly essential. Circular RNAs (CircRNAs) are a kind of endogenous non-coding RNA with stable structure, the long half-life, and tumor specificity. It can be used as a diagnostic marker for tumors. Using circRNA sequencing technology screened three pairs of GC and adjacent tissues, and circRNAs with significant expression differences were screened out. The circular structure and characteristics of circPTPN22 were determined by RT-qPCR, agarose gel electrophoresis, Sanger sequencing, RNase R, and actinomycin D assays. Cell Counting Kit‐8, colony formation, Transwell, Wound healing, tumor formation in mice and western blotting assays were used to detect the effects of circPTPN22 on the proliferation, invasion, migration, tumor growth of GC cells in vitro and protein expression. CircPTPN22 is up-regulated and positively correlated with metastasis in GC tissues, cells, and plasma. RT-qPCR results showed that circPTPN22 had good diagnostic efficacy and could be used to predict the prognosis of GC patients. In vitro and vivo experiments showed that the downregulation of circPTPN22 could inhibit cell proliferation, migration, and invasion through the epithelial-mesenchymal transformation (EMT) pathway. CircPTPN22 may regulate GC progression through the competitive binding of miRNAs. CircPTPN22 can be used as a potential diagnostic and prognostic marker for GC and can inhibit cell proliferation and metastasis through the competitive binding of miRNA to inhibit the EMT pathway.

Serum miR-30d as a novel biomarker for multiple myeloma and its antitumor role in U266 cells through the targeting of the MTDH/PI3K/Akt signaling pathway

Abstract: Multiple myeloma (MM) is a hematological tumor and is characterized by the infiltration of malignant clonal plasma cells (PCs) in bone marrow. MicroRNAs (miRNAs or miRs) have been reported to play an important role in the genesis and progression of MM. However, little is known about the clinical diagnostic value and biological functions of miR-30d in MM. In this study, to investigate the role of miR-30d in MM, we used reverse transcription-quantitative polymerase chain reaction quantitative (RT-qPCR) to detect the relative expression level of miR-30d in the serum of 81 patients with primary MM and 78 healthy donors (HDs). The biological functions of miR-30d were then assessed by CCK-8 assay, flow cytometric analysis of apoptosis and western blot (WB) analysis in U266 cells. Moreover, the confirmation of the target gene of miR-30d was conducted by luciferase reporter assay. Our results indicated that miR-30d expression was significantly downregulated in the serum of patients with primary MM compared with that of the HDs and that it was significantly associated with several clinical indicators of MM. Further cell functional analyses using the U266 cells revealed that miR-30d functions as a tumor suppressor gene in MM by inhibiting cell viability and promoting cell apoptosis. Moreover, miR-30d was confirmed to directly bind to the 3'UTR of its target gene, metadherin (MTDH) and inhibit the activation of the downstream PI3K/Akt signaling pathway. On the whole, the findings of this study indicate that the serum expression level of miR-30d is of great significance to the diagnosis and treatment monitoring of patients with MM. Moreover, miR-30d carries out its antitumor role in U266 cells through the inhibition of the activation of the PI3K/Akt signaling pathway by negatively regulating MTDH, which reveals its potential for use as a therapeutic target for MM.

Clinical significance of circulating tumor cells from lung cancer patients using microfluidic chip

Abstract: Circulating tumor cells (CTCs) exist in the peripheral blood and have an important role in the disease development, tumor metastasis and clinical surveillance, especially in the process of metastasis. However, the technology of detecting CTCs still had a large challenge since they were rare in the peripheral blood. Here, we developed a size-based microfluidic chip, which contained array and filter channel array that could enrich CTCs from blood samples more quickly and conveniently. Combined with clinical specimen, we analyzed CTCs in 200 lung cancer patients by this microfluidic chip. The microfluidic device has high specificity and sensitivity in detecting CTCs (86.0% sensitivity and 98% specificity). Furthermore, the number of CTCs showed a increasing trend according to the stage of the disease (the mean number of I stage 5.0 ± 5.121 versus II stage 8.731 ± 6.36 versus III stage 16.81 ± 9.556 versus IV stage 28.72 ± 17.39 cells/mL, P < 0.05). The number of CTCs was concurrent with the condition of pathological type and metastasis patients. Compared to conventional markers like CEA, CY211, SCC, CTCs showed a higher positive rate in diagnosed patients. The advanced microfluidic device could capture tumor cells without reliance on cell surface expression markers and provide a fast, convenient, economical method in detecting CTCs, thereby offering potential to design effective and individualized cancer therapies.

CircHAS2 promotes the proliferation, migration, and invasion of gastric cancer cells by regulating PPM1E mediated by hsa-miR-944.

Abstract: Gastric cancer (GC) is considered one of the most common gastrointestinal malignancies worldwide. Circular RNAs (circRNAs) are a new class of endogenous noncoding RNAs, which can be used as biomarkers and therapeutic targets for many tumors. However, the role and potential regulatory mechanisms of circRNAs in GC remain unclear. In this study, we demonstrated that a specific circRNA, circHAS2, was upregulated in GC tissues and cells and was positively correlated with tumor metastasis. In vitro experiments demonstrated that circHAS2 knockdown or the addition of hsa-miR-944 mimics inhibited the proliferation, migration, and invasion ability of GC cells and affected the epithelial-mesenchymal transition. In addition, hsa-miR-944 interacted with protein phosphatase, Mg2+/Mn2+-dependent 1E (PPM1E), and was found to be a target gene of circHAS2. The upregulation of PPM1E reversed the effects of circHAS2 knockout on GC cells. The circHAS2/hsa-miR-944/PPM1E axis may be involved in the progression of GC; thus, circHAS2 may be a potential biomarker and therapeutic target for GC.

Microfluidics for studying metastatic patterns of lung cancer

Abstract: The incidence of lung cancer continues to rise worldwide. Because the aggressive metastasis of lung cancer cells is the major drawback of successful therapies, the crucial challenge of modern nanomedicine is to develop diagnostic tools to map the molecular mechanisms of metastasis in lung cancer patients. In recent years, microfluidic platforms have been given much attention as tools for novel point-of-care diagnostic, an important aspect being the reconstruction of the body organs and tissues mimicking the in vivo conditions in one simple microdevice. Herein, we present the first comprehensive overview of the microfluidic systems used as innovative tools in the studies of lung cancer metastasis including single cancer cell analysis, endothelial transmigration, distant niches migration and finally neoangiogenesis. The application of the microfluidic systems to study the intercellular crosstalk between lung cancer cells and surrounding tumor microenvironment and the connection with multiple molecular signals coming from the external cellular matrix are discussed. We also focus on recent breakthrough technologies regarding lab-on-chip devices that serve as tools for detecting circulating lung cancer cells. The superiority of microfluidic systems over traditional in vitro cell-based assays with regard to modern nanosafety studies and new cancer drug design and discovery is also addressed. Finally, the current progress and future challenges regarding printable and paper-based microfluidic devices for personalized nanomedicine are summarized.

Diagnostic Value of Concentration of Circulating Cell-Free DNA in Breast Cancer: A Meta-Analysis.

Abstract: The diagnostic value of the concentration of circulating cell-free DNA (cfDNA) for breast cancer has generated inconsistent results. The aim of this study was to evaluate the first diagnostic value of the concentration of cfDNA for breast cancer by meta-analysis. Studies were retrieved by searching PubMed, Cochrane Library, and Web of Science before June 2018. Sensitivity, specificity, diagnostic odds ratio (DOR), the summary receiver operating characteristic (SROC) curve, and the area under curve (AUC) were used to summarize overall diagnostic performance. The random-effects model was used to calculate the pooled statistics. Subgroup analysis and meta-regression analysis were carried out to detect the source of heterogeneity. A total of 13 studies were identified with 1,087 breast cancer patients and 720 healthy controls. Overall, the pooled sensitivity and specificity of concentration of cfDNA for breast cancer were 87% (95% CI, 73-94%) and 87% (95% CI, 79-93%), respectively. The pooled DOR was 32.93 (95% CI, 13.52-80.19) and the SROC curve revealed an AUC of 0.93 (95% CI, 0.91-0.95). Meta-regression analysis showed that no covariate had a significant correlation with relative DOR (RDOR). Publication bias was not detected in this meta-analysis. This meta-analysis indicates that the concentration of cfDNA has potential first diagnostic value for breast cancer and plasma may be a better source of cfDNA for detection of breast cancer.

Microfluidic applications on circulating tumor cell isolation and biomimicking of cancer metastasis

Abstract: The prognosis of malignant tumors is challenged by insufficient means to effectively detect tumors at early stage. Liquid biopsy using circulating tumor cells (CTCs) as biomarkers demonstrates a promising solution to tackle the challenge, because CTCs play a critical role in cancer metastatic process via intravasation, circulation, extravasation, and formation of secondary tumor. However, the effectiveness of the solution is compromised by rarity, heterogeneity, and vulnerability associated with CTCs. Among a plethora of novel approaches for CTC isolation and enrichment, microfluidics leads to isolation and detection of CTCs in a cost-effective and operation-friendly way. Development of microfluidics also makes it feasible to model the cancer metastasis in vitro using a microfluidic system to mimick the in vivo microenvironment, thereby enabling analysis and monitor of tumor metastasis. This paper aims to review the latest advances for exploring the dual-roles microfluidics has played in early cancer diagnosis via CTC isolation and investigating the role of CTCs in cancer metastasis; the merits and drawbacks for dominating microfluidics-based CTC isolation methods are discussed; biomimicking cancer metastasis using microfluidics are presented with example applications on modelling of tumor microenvironment, tumor cell dissemination, tumor migration, and tumor angiogenesis. The future perspectives and challenges are discussed.