MicroRNA expression profiling and target gene analysis in gastric cancer

Glioma stem cell-derived exosomes induce the transformation of astrocytes via the miR-3065-5p/DLG2 signaling axis

Tumor-associated astrocytes (TAAs) in the glioblastoma microenvironment play an important role in tumor development and malignant progression initiated by glioma stem cells (GSCs). In the current study, normal human astrocytes (NHAs) were cultured and continuously treated with GSC-derived exosomes (GSC-EXOs) induction to explore the mechanism by which GSCs affect astrocyte remodeling. This study revealed that GSC-EXOs can induce the transformation of NHAs into TAAs, with relatively swollen cell bodies and multiple extended processes. In addition, high proliferation, elevated resistance to temozolomide (TMZ), and increased expression of TAA-related markers (TGF-β, CD44, and tenascin-C) were observed in the TAAs. Furthermore, GSC-derived exosomal miR-3065-5p could be delivered to NHAs, and miR-3065-5p levels increased significantly in TAAs, as verified by miRNA expression profile sequencing and Reverse transcription polymerase chain reaction. Overexpression of miR-3065-5p also enhanced NHA proliferation, elevated resistance to TMZ, and increased the expression levels of TAA-related markers. In addition, both GSC-EXO-induced and miR-3065-5p-overexpressing NHAs promoted tumorigenesis of GSCs in vivo. Discs Large Homolog 2 (DLG2, downregulated in glioblastoma) is a direct downstream target of miR-3065-5p in TAAs, and DLG2 overexpression could partially reverse the transformation of NHAs into TAAs. Collectively, these data demonstrate that GSC-EXOs induce the transformation of NHAs into TAAs via the miR-3065-5p/DLG2 signaling axis and that TAAs can further promote the tumorigenesis of GSCs. Thus, precisely blocking the interactions between astrocytes and GSCs via exosomes may be a novel strategy to inhibit glioblastoma development, but more in-depth mechanistic studies are still needed.

Landscape of Innovative Methods for Early Diagnosis of Gastric Cancer: A Systematic Review

From a global perspective, gastric cancer (GC) persists as a significant healthcare issue. In the Western world, the majority of cases are discovered at late stages, when the treatment is generally unsuccessful. There are no organized screening programs outside of Asia (Japan and Republic of Korea). Traditional diagnosis techniques (such as upper endoscopy), conventional tumor markers (CEA, CA19-9, and CA72-4), radiographic imaging, and CT scanning all have drawbacks. The gold standard for the earliest detection of cancer and related premalignant lesions is still endoscopy with a proper biopsy follow-up. Since there are currently no clinically approved biomarkers for the early diagnosis of GC, the identification of non-invasive biomarkers is expected to help improve the prognosis and survival rate of these patients. The search for new screening biomarkers is currently underway. These include genetic biomarkers, such as circulating tumor cells, microRNAs, and exosomes, as well as metabolic biomarkers obtained from biofluids. Meanwhile, cutting-edge high-resolution endoscopic technologies are demonstrating promising outcomes in the visual diagnosis of mucosal lesions with the aid of linked color imaging and machine learning models. Following the PRISMA guidelines, this study examined the articles in databases such as PubMed, resulting in 167 included articles. This review discusses the currently available and emerging methods for diagnosing GC early on, as well as new developments in the endoscopic detection of early lesions of the stomach.

The clinical validity of miR-126 as a prognostic marker in epithelial ovarian cancer

BACKGROUND

Ovarian cancer is the leading cause of gynecological cancer related death in females worldwide. Our previous study demonstrated that decreased expression of microRNA (miR-126) promoted ovarian cancer angiogenesis and invasion by targeting VEGF-A. This study aimed to evaluate the clinical validity of miR-126 as a prognostic marker for epithelial ovarian cancer (EOC).

PATIENT CONCERNS

The patients with EOC ranged in age from 27 to 79 years, with a mean age of 57 years.

DIAGNOSIS

All patients had never had chemotherapy or biotherapy, and the diagnoses were confirmed pathologically in all cases.

METHODS

MiR-126 levels in EOC tissue and normal ovaries were determined by qRT-PCR. Its prognostic value was analyzed using the Cox proportional hazards regression model. Survival curves were drawn using the Kaplan-Meier method.

RESULTS

In this study, we found that compared to normal tissues, miR-126 expression was lower in EOC tissues, particularly in omental metastases. Though in our previous study we found that miR-126 may inhibit proliferation and invasion in EOC cell lines, but in this study patients with elevated miR-126 expression exhibited poor overall survival and relapse free survival. Multivariate Cox regression analysis showed that miRNA-126 was an independent prognostic factor for poor relapse-free survival (P = .044). Receiver operating characteristic analysis showed that the area under the curve of miR-126 was 0.806 (95% confidence interval, 0.669-0.942).

CONCLUSION

In this study, we established miR-126 as a potential independent biomarker for predicting recurrence in patients with EOC.

Biomarkers of gastric cancer: current advancement

Gastric cancer (GC) is one of the most prevalent malignant types worldwide, especially in East Asia. Due to its frequently advanced stage at diagnosis, the mortality from GC is high and the prognosis is still unsatisfactory. Thus, early detection using effective screening approaches is vital to decrease the morbidity and mortality of GC. Interestingly, biomarkers can be used for diagnosis, prediction of sensitivity to treatment, and prognosis in GC. The potential biomarkers detectable in liquid biopsies such as circulating tumor cells (CTCs), long non-coding RNAs (lncRNAs), cell-free DNA (cfDNA), microRNAs, and exosomes reveal numerous information regarding the early prediction and the outcomes for GC patients. Additionally, using the novel serum biomarkers has opened up new opportunities for diagnosing and monitoring patients with GC. This review mainly summarizes the novel progress and approaches in GC biomarkers, which could be potentially used for early diagnosis and therapy monitoring. Meanwhile, we also discussed the advantages, disadvantages, and future perspectives of GC biomarkers.

miR-31-3p functions as a tumor suppressor by directly targeting GABBR2 in prostate cancer

MicroRNAs are key regulators of gene expression in tumorigenesis. In this study, we investigated the tumor-suppressive function of miR-31-3p. Analysis of the Gene Expression Omnibus database revealed that the expression of miR-31-3p in prostate cancer tissues is lower than that in adjacent normal tissues from patients with prostate cancer. Moreover, miR-31-3p induces apoptosis in DU145, PC-3, and LNCap prostate cancer cells, while those transfected with miR-31-3p exhibit significantly decreased cell proliferation, migration, invasiveness, and tumor sphere-forming ability, as determined using the cell counting kit-8, transwell, and sphere-forming assays. Further analysis revealed that GABBR2 is a direct target of miR-31-3p. Within a DU145 xenograft murine model, intratumoral injection of a miR-31-3p mimic suppresses tumor growth. Taken together, the findings of this study suggest that miR-31-3p performs a novel tumor-suppressive function in prostate cancer and may represent a novel target for anti-prostate cancer miRNA therapeutics.

CircRNA protein tyrosine phosphatase receptor type a suppresses proliferation and induces apoptosis of lung adenocarcinoma cells via regulation of microRNA-582-3p

Circular RNAs (circRNAs) are associated with cancer progression. The present study aimed to examine the function of circRNA protein tyrosine phosphatase receptor type A (circRNA_PTPRA) in lung cancer cells and elucidate the underlying molecular mechanisms. The levels of circRNA_PTPRA and microRNA (miRNA/miR)-582-3p were measured in lung cancer tissue and cells using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Cell proliferation and apoptosis were evaluated using an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry, respectively. The expression of cyclin D1, caspase-3, and cleaved caspase-3 was assessed via western blotting. The sites of circRNA_PTPRA/miR-582-3p interaction were identified using StarBase, and validated using a dual-luciferase reporter assay. We observed that circRNA_PTPRA levels were remarkably decreased, and miR-582-3p expression was up-regulated in lung cancer tissues and cells. circRNA_PTPRA directly interacts with miR-582-3p and downregulates miR-582-3p expression in lung cancer cells. Moreover, an miR-582-3p inhibitor decreased lung cancer cell proliferation and promoted apoptosis. The overexpression of circRNA_PTPRA decreased cell proliferation and increased apoptotic cell numbers, whereas miR-582-3p overexpression reversed these effects. These findings demonstrate that the up-regulation of circRNA_PTPRA significantly reduces lung cancer cell proliferation and induces apoptosis by regulating miR-582-3p expression.

PHLPP1 Overexpression was Associated With a Good Prognosis With Decreased AKT Activity in Gastric Cancer

Introduction: The aim of this study was to perform a clinicopathologic analysis of PHLPP1 expression in gastric cancer patients and analyze AKT activity with chemotherapy drug treatment in cancer subtypes. Materials and Methods: Surgically resected gastric cancer tissue specimens were obtained from 309 patients who underwent gastrectomy, and PHLPP1 expression was validated by tissue microarray analysis with immunohistochemistry. We assessed whether PHLPP1 selectively dephosphorylates Ser473 of AKT in an in-vitro study. Results: We found that the PHLPP1 overexpression (OE) group showed significantly greater proportions of differentiated subtype samples and early T stage samples, lower lymph node metastasis, and lower TNM stage than the PHLPP1 underexpression (UE) group. The overall survival of the PHLPP1-OE group was significantly higher (53.39 ± 0.96 months) than that of the PHLPP1-UE group (47.82 ± 2.57 months) (P = .01). In vitro analysis, we found that the PHLPP1-OE group showed a significant decrease in relative AKT S-473 levels in both cell lines (MKN-74 and KATO-III). We found that treatment with chemotherapy drugs decreased the activity of Ser473 in the MKN-74 cell line with PHLPP1 OE, but it did not affect the activity of Ser473 in KATO-III cells. Conclusion: We found that patients who overexpressed PHLPP1 showed low recurrence and good prognosis. PHLPP1 was found to work by lowering the activity of AKT Ser473 in gastric cancer. Additionally, we found a clue regarding the mechanism of chemotherapeutic drug resistance in a cell line of signet ring cell origin and will uncover this mechanism in the future.

A new insight into sex-specific non-coding RNAs and networks in response to SARS-CoV-2

SARS-CoV-2 is the RNA virus responsible for COVID-19, the prognosis of which has been found to be slightly worse in men. The present study aimed to analyze the expression of different mRNAs and their regulatory molecules (miRNAs and lncRNAs) to consider the potential existence of sex-specific expression patterns and COVID-19 susceptibility using bioinformatics analysis. The binding sites of all human mature miRNA sequences on the SARS-CoV-2 genome nucleotide sequence were predicted by the miRanda tool. Sequencing data was excavated using the Galaxy web server from GSE157103, and the output of feature counts was analyzed using DEseq2 packages to obtain differentially expressed genes (DEGs). Gene set enrichment analysis (GSEA) and DEG annotation analyses were performed using the ToppGene and Metascape tools. Using the RNA Interactome Database, we predicted interactions between differentially expressed lncRNAs and differentially expressed mRNAs. Finally, their networks were constructed with top miRNAs. We identified 11 miRNAs with three to five binding sites on the SARS-COVID-2 genome reference. MiR-29c-3p, miR-21-3p, and miR-6838-5p occupied four binding sites, and miR-29a-3p had five binding sites on the SARS-CoV-2 genome. Moreover, miR-29a-3p, and miR-29c-3p were the top miRNAs targeting DEGs. The expression levels of miRNAs (125, 181b, 130a, 29a, b, c, 212, 181a, 133a) changed in males with COVID-19, in whom they regulated ACE2 expression and affected the immune response by affecting phagosomes, complement activation, and cell-matrix adhesion. Our results indicated that XIST lncRNA was up-regulated, and TTTY14, TTTY10, and ZFY-AS1 lncRN as were down-regulated in both ICU and non-ICU men with COVID-19. Dysregulation of noncoding-RNAs has critical effects on the pathophysiology of men with COVID-19, which is why they may be used as biomarkers and therapeutic agents. Overall, our results indicated that the miR-29 family target regulation patterns and might become promising biomarkers for severity and survival outcome in men with COVID-19.

Predicting Associations of miRNAs and Candidate Gastric Cancer Genes for Nanomedicine

Nanoscale miRNAs regulate the synthesis of most human proteins involved in differentiation, proliferation, cell cycle, apoptosis, and other processes associated with the growth and the development of an organism. miRNAs also play a number of important roles in the development of gastric cancer. In this work, we studied the quantitative characteristics of miRNA interactions with 69 candidate gastric cancer genes using bioinformatics approaches. To this end, the MirTarget program was used, which determines the characteristics of miRNA binding to mRNA in the 5′UTR, CDS, and 3′UTR. Associations of miRNAs with alternative target genes and associations of genes with alternative miRNAs were established. The cluster organization of miRNA binding sites (BSs) in mRNA was revealed, leading to the emergence of miRNA competition for binding to the mRNA of a target gene. Groups of target genes with clusters of overlapping BSs include miR-5095, miR-619-5p, miR-1273 family, miR-466, ID01030.3p-miR, ID00436.3p-miR, miR-574-5p, and ID00470.5p-miR. In the defined associations of target genes and miRNAs, miRNA BSs are organized into clusters of multiple BSs, which facilitate the design and the development of a system of chips that can be used to control the state of miRNA and target genes associations in gastric cancer.