CA : A Cancer Journal for Clinicians

MicroRNAs (miRNAs) are endogenous ∼23 nt RNAs that play important gene-regulatory roles in animals and plants by pairing to the mRNAs of protein-coding genes to direct their posttranscriptional repression. This review outlines the current understanding of miRNA target recognition in animals and discusses the widespread impact of miRNAs on both the expression and evolution of protein-coding genes.

MicroRNAs: Target Recognition and Regulatory Functions

The operative treatment of pectus excavatum.

Ubiquitination is a post-translational modification (PTM) that is essential for balancing numerous physiological processes. To enable delineation of protein ubiquitination at a site-specific level, we generated an antibody, denoted UbiSite, recognizing the C-terminal 13 amino acids of ubiquitin, which remain attached to modified peptides after proteolytic digestion with the endoproteinase LysC. Notably, UbiSite is specific to ubiquitin. Furthermore, besides ubiquitination on lysine residues, protein N-terminal ubiquitination is readily detected as well. By combining UbiSite enrichment with sequential LysC and trypsin digestion and high-accuracy MS, we identified over 63,000 unique ubiquitination sites on 9,200 proteins in two human cell lines. In addition to uncovering widespread involvement of this PTM in all cellular aspects, the analyses reveal an inverse association between protein N-terminal ubiquitination and acetylation, as well as a complete lack of correlation between changes in protein abundance and alterations in ubiquitination sites upon proteasome inhibition.

UbiSite approach for comprehensive mapping of lysine and N-terminal ubiquitination sites

https://pure.rug.nl/ws/files/66477432/1_s2.0_S156816371830093X_main.pdf

Towards frailty biomarkers: Candidates from genes and pathways regulated in aging and age-related diseases

MicroRNAs (miRNAs) play critical roles in cancer development and progression. In this study, we examined the roles and molecular mechanisms of miR-342-3p in human non-small cell lung cancer (NSCLC). The results showed that miR-342-3p is downregulated in NSCLC cell lines and tissues, and its overexpression induces significant inhibition of NSCLC cell proliferation, invasion, and tumor growth in nude mice. In addition, miR-342-3p repressed RAP2B expression through interactions with its 3'-UTR region. Restoration of RAP2B expression reversed miR-342-3p-mediated inhibitory activity in NSCLC cells. Finally, analyses of miR-342-3p and RAP2B levels in NSCLCs revealed that miR-342-3p inversely correlated with RAP2B mRNA expression. Our collective findings provide preliminary evidence that miR-342-3p acts as a tumor suppressor in NSCLC through repression of RAP2B.

miR-342-3p targets RAP2B to suppress proliferation and invasion of non-small cell lung cancer cells

Ubiquitination is a post-translational modification that plays a role in several cellular processes including cell cycle progression, cell proliferation, DNA replication and apoptosis. Ubiquitin-mediated signaling is frequently altered in cancer cells. Several tumor suppressors and oncogenes interact with enzymes of the ubiquitin-proteasome pathway that function in ubiquitin conjugation and deconjugation. Increasing evidence indicates that the ubiquitin-proteasome system (UPS) plays an important role in cancer development. Several small molecule inhibitors of the UPS have been applied to the treatment of cancer. The current review focuses on the role of the UPS in cancer development and the development of UPS inhibitors for cancer treatment.

The role of the ubiquitin-proteasome pathway in cancer development and treatment.

Deubiquitinases (DUBs) and noncoding RNAs have been the subjects of recent extensive studies regarding their roles in lung cancer, but the mechanisms involved are largely unknown. In our study, we used The Cancer Genome Atlas data set and bioinformatics analyses and identified USP21, a DUB, as a potential contributor to oncogenesis in non-small-cell lung cancer (NSCLC). We further demonstrated that USP21 was highly expressed in NSCLCs. We then conducted a series of in vitro and in vivo assays to explore the effect of USP21 on NSCLC progression and the underlying mechanism involved. USP21 promoted NSCLC cell proliferation, migration, and invasion and in vivo tumor growth by stabilizing a well-known oncogene, Yin Yang-1 (YY1), via mediating its deubiquitination. Furthermore, YY1 transcriptionally regulates the expression of SNHG16. Moreover, StarBase bioinformatics analyses predicted that miR-4500 targets SNHG16 and USP21. A series of in vitro experiments indicated that SNHG16 increased the expression of USP21 through miR-4500. In summary, the USP21/YY1/SNHG16 axis plays a role in promoting the progression of NSCLC. Therefore, the USP21/YY1/SNHG16/miR-4500 axis may be a potential therapeutic target in NSCLC treatment.

The USP21/YY1/SNHG16 axis contributes to tumor proliferation, migration, and invasion of non-small-cell lung cancer.

MicroRNAs are a class of small non-coding RNAs that play essential roles in cancer development and progression. Recent studies suggested that abnormal expression of miRNAs occurs frequently in non-small cell lung cancer (NSCLC) tissues compared to adjacent normal tissues. In this study, we investigated the expression and the biological roles of miR-106a in non-small cell lung cancer. Our results showed that miR-106a was up-regulated in NSCLC tissues and cell lines. Inhibition of miR-106a in NSCLC cells substantially inhibited cell proliferation, migration, and invasion. Phosphatase and tensin homolog (PTEN) was identified as a direct target of miR-106a, and over-expression of miR-106a suppressed PTEN by direct binding to its 3'-untranslated region (3'-UTR). Furthermore, the presence of miR-106a was inversely correlated with PTEN in NSCLC tissues. Overall, this study suggested that miR-106a inhibited the growth and metastasis of NSCLC cells by decreasing PTEN expression. These data provide novel insights with potential therapeutic applications for the treatment of NSCLC.

miR-106a promotes growth and metastasis of non-small cell lung cancer by targeting PTEN

Introduction: Long non coding RNAs (lncRNAs) have emerged recently as major players in tumor biology and may be used for cancer diagnosis, prognosis, and potential therapeutic targets. The lncRNA HMlincRNA717, a newly identified lncRNA, was demonstrated to be down-regulated in gastric cancer. However, little is known about its role in non small cell lung cancer (NSCLC). Methods: Expression of lncRNA HMlincRNA717 in tumor and their matched non-tumor tissues was determined by quantitative real-time PCR (qRT-PCR) in NSCLC patients. Then, we analyzed the potential relationship between lncRNA HMlincRNA717 expression levels in tumor tissues and clinicopathological features of NSCLC, and clinical outcome. Results: lncRNA HMlincRNA717 expression level was significantly decreased in NSCLC tissues in comparison to adjacent non-tumor tissues. It was also proved that HMlincRNA717 expression was to be associated with NSCLC histological grade, and lymph node metastasis. In addition, survival analysis proved that down-regulated HMlincRNA717 expression was associated with poor overall survival of NSCLC patients. Multivariate survival analysis also proved that HMlincRNA717 was an independent prognostic factor for NSCLC patients. Conclusions: The present study showed the down-regulation of HMlincRNA717 and its association with tumor progression in human NSCLC. It also provided that HMlincRNA717 expression was an independent prognostic factor for patients with NSCLC, which might be a potential prognostic biomarker and therapeutic target for NSCLC.

Haibo Xiao

Papers

miR-342-3p targets RAP2B to suppress proliferation and invasion of non-small cell lung cancer cells

The role of the ubiquitin-proteasome pathway in cancer development and treatment.

The USP21/YY1/SNHG16 axis contributes to tumor proliferation, migration, and invasion of non-small-cell lung cancer.

miR-106a promotes growth and metastasis of non-small cell lung cancer by targeting PTEN

LncRNA HMlincRNA717 is down-regulated in non-small cell lung cancer and associated with poor prognosis.