LncRNA XIST interacts with miR-454 to inhibit cells proliferation, epithelial mesenchymal transition and induces apoptosis in triple-negative breast cancer

Triple-negative breast cancer (TNBC) is a one of the subtypes of breast cancer which accounts for approximately 10–20% of all breast cancers. LncRNA XIST (XIST) is reported to be dysfunctional in numerous tumortypes and is involved in the key pathways of cancer initiation, progression and metastasis. Thus, in the presentstudy, we explored the detailed molecular mechanism of XIST in TNBC. XIST was down-regulated in TNBCtissues and cell lines. Overexpressed XIST inhibited cell proliferation, epithelial mesenchymal transition(EMT) and induced apoptosis in vitro as well as suppressed TNBC tumor growth in vivo. MicroRNA (miR)-454 was up-regulated in TNBC tissues and cell lines. Knockdown of miR-454 inhibited TNBC progression bysuppressing cell proliferation, EMT and inducing cell apoptosis. Moreover, miR-454 was predicted andconfirmed to be a target of XIST, and rescue assay indicated that overexpressed miR-454 could reverse XISTrestoration mediated-anti-tumor effects on TNBC cells. In conclusion, XIST interacts with miR-454 to inhibitcells proliferation, EMT and induce apoptosis in TNBC, indicating a promising treatment strategy for TNBCpatients.

Silencing LncRNA HOXD-AS1 enhances the radiosensitivity of H460 cells by regulating miR-454-3p expression / 中华放射肿瘤学杂志

Objective To explore the effect of LncRNA HOXD-AS1 on the radiosensitivity of H460 cells by targeting the regulation of miR-454-3p expression. Methods H460 cells were irradiated with 0, 2, 4, 6 and 8 Gy, and the expression levels of HOXD-AS1 and miR-454-3p were detected by qRT-PCR. Cell apoptosis rate were measured by flow cytometry experiments. Cell cloning experiments were used to detect cell radiosensitivity. The protein expression levels of Caspase-3, Cyclin D1 and γ-H2AX were detected by Western blot. Results The expression of HOXD-AS1 in H460 cells was significantly increased after X-ray irradiation ( P<0.05) , while the expression of miR-454-3p was significantly decreased ( P<0.05) . Silencing HOXD-AS1 significantly promoted apoptosis, increased radiosensitivity of lung cancer cells, promoted Caspase-3, γ-H2AX protein expression, and inhibited Cyclin D1 expression. HOXD-AS1 could target the expression of miR-454-3p. Conclusion Silencing HOXD-AS1 can promote the apoptosis of lung cancer cells and inhibit cell survival by targeting miR-454-3p to increase the radiosensitivity of lung cancer cells.

Expression of tumor suppressor factors SEMA3F, CYLD and miR-454 in rectal cancer patients / 中国现代普通外科进展

Objective:To study the expression of tumor suppressor factors SEMA3F,CYLD and miR-454 in rectal cancer.Methods:21 patients with colorectal cancer admitted in our hospital from January to March in 2016 were selected as the study materials.The tumor inhibitoryfactor SEMA3F in rectal cancer tissue,cancerous surrounding tissue and normal rectum tissue were detected respectively,CYLD and miR-454,and to analyze the correlation between tumor suppressor factors SEMA3F,CYLD and miR-454,and to explore their roles in the carcinogenesis and progression of rectal cancer.Results:The expression of SEMA3F,CYLD and miR-454 in cancer tissue,paracancer tissue and normal tissue were statistically significant (P＜0.01).The levels of SEMA3F and CYLD were significantly lower in patients with metastasis than those without metastasis,and miR-454 was significantly higher than that in patients without metastasis (P＜0.01).The expression level of SEMA3F and CYLD in CRC tissues was significantly higher than that in moderately and poorly differentiated tissues,and the expression of miR-454 was significantly lower than that in moderately and poorly differentiated ones (P＜0.01).There was significant negative correlation between tumor suppressor CYLD and miR-454 (r=-0.971,P＜0.01).There was a significant negative correlation between tumor inhibitory factor SEMA3F and miR-454(r=-0.955,P＜0.01).Conclusion:The tumor suppressor factors SEMA3F and CYLD play an important role in inhibiting the formation and proliferation of cancer cells in colorectal cancer.The expression of tumor suppressor factors SEMA3F and CYLD in colorectal cancer is high in the early stage and gradually declines with the progression of the disease.MiR-454 can promote the growth of rectal cancer cells The expression of tumor suppressor factors SEMA3F,CYLD and miR-454 in colorectal carcinoma were significantly higher than those in SEMA3F and CYLD.The expression of tumor suppressor factors such as SEMA3F,CYLD and miR-454 were significantly correlated with the progression and prognosis of rectal cancer The evaluation has important reference value.