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BACKGROUND In recent years, the incidence of gastric cancer (GC) has been increasing worldwide. Emerging evidence shows that microRNAs (miRs) may be involved in the pathogenesis of GC. Thus, this study explored the mediatory role of miR-495 in GC chemosensitivity, and investigated the mechanism by which it affects the biological behaviors of GC cells via the mTOR signaling pathway. MATERIAL AND METHODS After GC and paracancerous tissue collection, the positive rate of ERBB2 and mTOR was evaluated by immunohistochemistry. Subsequently, the expression of miR-495, ERBB2, and mTOR was determined by RT-qPCR and Western blot analysis. Next, the targeting relationship between miR-495 and ERBB2 was confirmed by dual-luciferase reporter gene assay. In addition, chemosensitivity and proliferation were detected by MTT assay and apoptosis was assessed by flow cytometry. RESULTS We found higher positive rates of ERBB2 and mTOR and decreased expression of miR-495 in GC tissues and showed that ERBB2 is the target gene of miR-495. Furthermore, we determined that overexpression of miR-495 and silencing of ERBB2 enhanced GC cell chemosensitivity and apoptosis, but inhibited GC cell proliferation. We also found that the effect of miR-495 inhibition was lost when ERBB2 was suppressed. CONCLUSIONS The key findings of our study demonstrate that the miR-495 exerts promotive effects on GC chemosensitivity via inactivation of the mTOR signaling pathway by suppressing ERBB2. The study provides reliable evidence supporting the use of miR-495 as a novel potential target in the chemotherapy of GC.

Emerging evidence has shown that circular RNAs (circRNAs) serve as a promising biomarker in different malignancies. Specifically, circ_001569 has been found to be upregulated in some types of human gastrointestinal cancer. In this study, we aimed to investigate clinical significances, diagnostic and prognostic values of circ_001569 in pancreatic cancer (PC), and identify its effects on the malignant behaviors of PC cells. The expression of circ_001569 was determined in 26 tissues samples and 97 plasma samples from PC patients by qRT-PCR. Relationship between circ_001569 expression and clinicopathological parameters was analyzed by Chi-square test. Diagnostic and prognostic values of circ_001569 were evaluated by ROC curves, Kaplan-Meier curves, and Cox regression analysis. The effects of circ_001569 on the proliferation, migration, invasion, and apoptosis of PC cells were assessed by MTT, wound healing, Transwell invasion assays, and flow cytometric analysis, respectively. Results showed that the expression of circ_001569 was upregulated in tissues and plasma of PC patients. High circ_001569 level was positively correlated with lymphatic metastasis, clinical stage, and venous invasion. Circ_001569 level was an independent prognostic indicator for overall survival rates of PC patients, and patients with high circ_001569 level had a poor prognosis. The AUC of circ_001569 was 0.716 (95% CI: 0.642-0.790) with a sensitivity and specificity of 62.76% and 74.29%, respectively. In vitro, circ_001569 silencing decreased cell proliferation, migration, and invasion, but promoted cell apoptosis of PC cells. Our data demonstrate that high circ_001569 level associates with tumor malignant behaviors, and may serve as a potential biomarker in the diagnosis and prognosis of PC.

Background Patients with lung adenocarcinoma (LUAD) have high mortality rate and poor prognosis. The LUAD cells display increased aerobic glycolysis, which generates energy required for their survival and proliferation. Deregulation of Wnt/β-catenin signaling pathway induces the metabolism switching and oncogenesis in tumor cells. RING finger protein 115 (RNF115) is an E3 ligase for ubiquitin-mediated degradation. Although the oncogenic functions of RNF115 have been revealed in breast tumor cells, the effect of RNF115 on lung cancer is still not clear. Methods RNF115 expression and its correlation with the features of LUAD patients were analyzed by using public database and our own cohort. The functions of RNF115 in proliferation and energy metabolism in LUAD cells were explored by downregulating or upregulating RNF115 expression. Results We demonstrated that RNF115 was overexpressed in LUAD tissues and its expression was positively correlated with the poor overall survival of LUAD patients. Moreover, RNF115 overexpression inhibited LUAD cell apoptosis and promoted cellular proliferation and metabolism in LUAD cells. On the contrary, RNF115 knockdown displayed reverse effects. Furthermore, the underlying mechanism of the biological function of RNF115 in LUAD was through regulating Wnt/β-catenin pathway via ubiquitination of adenomatous polyposis coli (APC). Conclusion The current study reveals a close association between RNF115 expression and prognostic conditions in LUAD patients and the oncogenic roles of RNF115 in LUAD at the first time. These findings may help establish the foundation for the development of therapeutics strategies and clinical management for lung cancer in future.

Long non-coding RNAs (lncRNAs) are emerging as important modulators of cancer progression, among which prostate cancer-associated transcript 1 (PCAT1) has been shown to be an oncogene in several tumors. However, the clinical significance and biological function of PCAT1 in endometrial carcinoma (EC) remain unclear. In this study, we used 89 EC tissues and HEC-1B, Ishikawa, RL95-2 and AN3CA EC cell lines. We found elevated expression levels of PCAT1 in EC tissues and cell lines using reverse transcription qPCR (RT-qPCR). The prognostic value of PCAT1 was determined using Kaplan–Meier survival and Cox regression analysis. The results showed that higher PCAT1 expression was positively correlated with FIGO stage, myometrial invasion, lymph node metastasis, and a shorter overall survival. A series of functional assays showed that the knockdown of PCAT1 by small interfering RNA (siRNA) targeting PCAT1 (siPCAT1) suppressed cell proliferation, migration and invasion, but promoted apoptosis. Western blot analysis further showed that B-cell lymphoma 2 (Bcl-2), vimentin and N-cadherin were downregulated, but E-cadherin and Bcl-2-associated death promoter (Bad) were upregulated in PCAT1-silenced EC cells. Taken together, our results underscore the oncogenic role of PCAT1 in EC and show that PCAT1 may be a potential therapeutic target in EC treatment.

Background. Long noncoding RNAs (lncRNAs) have been known to play important roles in the progression of various types of human cancer. LncRNA GATA3 antisense RNA 1, GATA3-AS1, has been reported to be associated with T-cell development and differentiation. However, the expression pattern and function of GATA3-AS1 in hepatocellular carcinoma (HCC) remain unknown. Methods. Real-time quantitative PCR (RT-qPCR) assay was conducted to detect GATA3-AS1 expression levels in 80 cases of pairs HCC tissues and matched normal tissues. Chi-squared (χ2) test was used to analyze the correlation between GATA3-AS1 expression and clinicopathologic variables. Survival curves were plotted using the Kaplan–Meier method and were compared via the log-rank test. The cell counting kit-8 (CCK-8) and wound scratch assays were applied to detect the effect of GATA3-AS1 knockdown and overexpression on cell growth and migration of HCC. RT-qPCR was performed for the detection of the phosphatase and tensin homolog (PTEN), cyclin-dependent kinase inhibitor 1A (CDKN1A), and tumor protein p53 (TP53) expression in HCC cells after GATA3-AS1 knockdown and overexpression. Results. GATA3-AS1 was significantly upregulated in HCC tissues compared with matched normal tissues. The high expression of GATA3-AS1 was significantly correlated with larger tumor size, advanced TNM stage, and more lymph node metastasis. High GATA3-AS1 expression was markedly correlated with shorter overall survival times of HCC patients. Furthermore, knockdown of GATA3-AS1 obviously inhibited Hep3B and HCCLM3 cell growth and migration, whereas overexpression of GATA3-AS1 had the opposite effects. In addition, GATA3-AS1 knockdown resulted in upregulated expression levels of tumor-suppressive genes, PTEN, CDKN1A, and TP53, in Hep3B and HCCLM3 cells, while restoration of GATA3-AS1 decreased PTEN, CDKN1A, and TP53 expression levels. Conclusion. Our data suggested that GATA3-AS1 promotes cell proliferation and metastasis of HCC by suppression of PTEN, CDKN1A, and TP53.

Aromatase inhibitors (AIs) are widely used in the treatment of hormone‑dependent breast cancer and as a result, aromatase inhibitor‑associated bone loss (AIBL) has become a major concern amongst patients receiving AI treatment. Modified Shu‑Gan‑Liang‑Xue decoction (mSGLXD), a clinical prescription, has been used for ameliorating AIBL in patients with breast cancer for decades and has achieved good clinical efficacy. However, the mechanism underlying how mSGLXD influences bone homeostasis and alleviates AIBL has remained elusive. In the present study, mSGLXD was supplemented with Rhizoma Drynariae containing phytoestrogens, and the safety of mSGLXD was evaluated. mSGLXD did not possess estrogenic activity and significantly inhibited the proliferation of estrogen receptor‑positive breast cancer cell line MCF‑7, which suggested that mSGLXD was safe for postmenopausal patients with breast cancer. Subsequently, the effects of mSGLXD alone or in combination with anastrozole on osteoblastic MC3T3‑E1 cell proliferation and differentiation were investigated. Cell counting kit‑8, reverse transcription‑polymerase chain reaction and biochemical methods, such as ELISA and alizarin red S staining, were used in the present study. It was revealed that mSGLXD not only stimulated MC3T3‑E1 cell proliferation, but also upregulated alkaline phosphatase and osteocalcin gene and protein expression levels. High concentrations of anastrozole (10 or 100 µmol/l) markedly inhibited MC3T3‑E1 cell proliferation, but this inhibitory effect was attenuated by mSGLXD. Furthermore, mSGLXD increased MC3T3‑E1 cell mineralization following β‑glycerophosphate and ascorbic acid induction. Therefore, the results of the present study suggested that mSGLXD may be a promising adjuvant therapy, with high safety and efficacy, for the prevention and treatment of AIBL in patients with breast cancer who receive AI treatment.

Background Overexpression of Metastasis-associated protein 1 (MTA1) in various cancer cells promotes tumor invasion and migration and predicts cancer patients’ poor prognosis. The pilot RNA-Seq data from our laboratory indicated that Epithelial cell adhesion molecule (EpCAM) was statistically reduced in MTA1-silencing cells. EpCAM has been recognized as more than a mere cell adhesion molecule and recent findings have revealed its causal role in mediating migratory and invasive capacity. Thus, this study was aimed to explore whether MTA1 was able to upregulate EpCAM expression and, consequently, modulate its effects on invasion and migration of the lung cancer cells as well as patients’ prognosis. Methods We checked the EpCAM expression by overexpressing or silencing MTA1 in lung cancer cells. Furthermore, these lung cancer cells with stably overexpressed or silenced MTA1 were transfected with siEpCAM or EpCAM-expressing plasmids and then subjected to western blot, invasion and migration assays. In addition, patients (n = 118) with early-stage lung cancer were enrolled in this study to confirm the correlations between MTA1 and EpCAM and pathoclinical parameters by using immunohistochemistry (IHC). All statistical analyses were performed with SPSS 20.0 statistical software. Results MTA1 upregulated EpCAM expression in lung cancer cell lines, and EpCAM overexpression rescued the inhibitory effects by silencing MTA1 on cell invasion and migration in vitro. What’s more, both MTA1 and EpCAM, correlated to each other, were overexpressed in lung cancer tissues and significantly correlated with their clinical stages, tumor diameters, lymph node metastasis. Multivariate analysis indicated that local advancement (p = 0.03), MTA1 overexpression (p = 0.001) and EpCAM overexpression (p = 0.045) of the lung cancer tissues remained significant in predicting unfavorable overall survival. Conclusions We revealed a new molecular mechanism of MTA1-mediated invasion and metastasis in lung cancer through downstream target EpCAM, and interfering with EpCAM function may be a novel therapeutic strategy for treatment of MTA1-overexpressing lung carcinoma.

Ai-Ling Liang,1–3,* Hai-Li Qian,4,* Ting-Ting Zhang,1–3 Ning Zhou,1–3 Hai-Juan Wang,4 Xi-Ting Men,4 Wei Qi,5 Ping-Ping Zhang,6 Ming Fu,4 Xiao Liang,4 Chen Lin,4 Yong-Jun Liu1–3 1Medical Molecular Diagnostics Key Laboratory of Guangdong, 2Department of Biochemistry and Molecular Biology, 3Department of Clinical Biochemistry, Guangdong Medical University, Dongguan, Guangdong, 4State Key Laboratory of Molecular Oncology, Cancer Institute, Chinese Academy of Medical Sciences, Beijing, 5Electroencephalogram Room, 6Department of Orthopedics, Guangdong Medical University Affiliated Hospital, Zhanjiang, Guangdong, People’s Republic of China *These authors contributed equally tothis study Abstract: Breast cancer is the most common cancer and the leading cause of cancer-related death among women worldwide, with urgent need to develop new therapeutics. Targeted therapy is a promising strategy for breast cancer therapy. Stromal-derived factor-1/CXC chemokine receptor 4 (CXCR4) has been implicated in the metastasis of breast cancer, which renders it to be therapeutic target. This study aimed to evaluate the anticancer effect of fused TAT–DV1–BH3 polypeptide, an antagonist of CXCR4, and investigate the underlying mechanism for the cancer cell-killing effect in the treatment of breast cancer in vitro and in vivo. This results in a potent inhibitory effect of fused TAT–DV1–BH3 polypeptide on tumor growth and metastasis in nude mice bearing established MDA-MB-231 tumors. Fused TAT–DV1–BH3 polypeptide inhibited the proliferation of MDA-MB-231 and MCF-7 cells but did not affect that of HEK-293 cells. The fused TAT–DV1–BH3 polypeptide colocalized with mitochondria and exhibited a proapoptotic effect through the regulation of caspase-9 and -3. Furthermore, the fused TAT–DV1–BH3 polypeptide suppressed the migration and invasion of the highly metastatic breast cancer cell line MDA-MB-231 in a concentration-dependent manner. Notably, the DV1-mediated inhibition of the stromal-derived factor-1/CXCR4 pathway contributed to the antimetastasis effect, evident from the reduction in the level of phosphoinositide 3 kinase and matrix metalloproteinase 9 in MDA-MB-231 cells. Collectively, these results indicate that the apoptosis-inducing effect and migration- and invasion-suppressing effect explain the tumor regression and metastasis inhibition in vivo, with the involvement of caspase- and CXCR4-mediated signaling pathway. The data suggest that the fused TAT–DV1–BH3 polypeptide is a promising agent for the treatment of breast cancer, and more studies are warranted to fully elucidate the therapeutic targets and molecular mechanism. Keywords: bifunctional, fused polypeptide, CXCR4, breast cancer, apoptosis, transfer

Gastric cancer (GC) is one of the leading causes of cancer-related mortality worldwide. Cancer stem cells (CSCs), which were first identified in acute myeloid leukemia and subsequently in a large array of solid tumors, play important roles in cancer initiation, dissemination and recurrence. CSCs are often transformed tissue-specific stem cells or de-differentiated transit amplifying progenitor cells. Several populations of multipotent gastric stem cells (GSCs) that reside in the stomach have been determined to regulate physiological tissue renewal and injury repair. These populations include the Villin+ and Lgr5+ GSCs in the antrum, the Troy+ chief cells in the corpus, and the Sox2+ GSCs that are found in both the antrum and the corpus. The disruption of tumor suppressors in Villin+ or Lgr5+ GSCs leads to GC in mouse models. In addition to residing GSCs, bone marrow-derived cells can initiate GC in a mouse model of chronic Helicobacter infection. Furthermore, expression of the cell surface markers CD133 or CD44 defines gastric CSCs in mouse models and in human primary GC tissues and cell lines. Targeted elimination of CSCs effectively reduces tumor size and grade in mouse models. In summary, the recent identification of normal GSCs and gastric CSCs has greatly improved our understanding of the molecular and cellular etiology of GC and will aid in the development of effective therapies to treat patients.

BACKGROUND: Chronic stress or prolonged administration of glucocorticoids suppresses proliferation and/or survival of newborn cells in adult rat dentate gyrus. Earlier we showed that administration of the glucocorticoid receptor antagonist mifepristone during the final 4 days of a 21 days period of corticosterone treatment fully normalized the number of newborn cells. Here we aimed to better understand how mifepristone achieves this effect and questioned whether an even shorter (single day) mifepristone treatment (instead of 4 days) also suffices to normalize neurogenesis.METHODS: We investigated various steps of the neurogenic process, using the immunohistochemical markers BrdU, doublecortin, proliferating cell nuclear antigen as well as glial fibrillary acidic protein, after 17 or 21 days of corticosterone (versus vehicle) treatment.RESULTS: Corticosterone primarily attenuates the proliferation of cells which subsequently develop into neurons; this is fully reversed by mifepristone. Surprisingly, the corticosteroid effects on neurogenesis can even be fully re-set by a single-day treatment with mifepristone (on day 18), despite the continued corticosterone exposure on subsequent days.CONCLUSIONS: Our results emphasize that studies into the therapeutical efficacy of new antidepressants, especially those targeting HPA-activity or the glucocorticoid receptor, should explore the possibility to reduce treatment duration.