MiR-219-5p inhibits prostate cancer cell growth and metastasis by targeting HMGA2

HMGA2 promotes cancer metastasis by regulating epithelial-mesenchymal transition

Epithelial-mesenchymal transition (EMT) is a complex physiological process that transforms polarized epithelial cells into moving mesenchymal cells. Dysfunction of EMT promotes the invasion and metastasis of cancer. The architectural transcription factor high mobility group AT-hook 2 (HMGA2) is highly overexpressed in various types of cancer (e.g., colorectal cancer, liver cancer, breast cancer, uterine leiomyomas) and significantly correlated with poor survival rates. Evidence indicated that HMGA2 overexpression markedly decreased the expression of epithelial marker E-cadherin (CDH1) and increased that of vimentin (VIM), Snail, N-cadherin (CDH2), and zinc finger E-box binding homeobox 1 (ZEB1) by targeting the transforming growth factor beta/SMAD (TGFβ/SMAD), mitogen-activated protein kinase (MAPK), and WNT/beta-catenin (WNT/β-catenin) signaling pathways. Furthermore, a new class of non-coding RNAs (miRNAs, circular RNAs, and long non-coding RNAs) plays an essential role in the process of HMGA2-induced metastasis and invasion of cancer by accelerating the EMT process. In this review, we discuss alterations in the expression of HMGA2 in various types of cancer. Furthermore, we highlight the role of HMGA2-induced EMT in promoting tumor growth, migration, and invasion. More importantly, we discuss extensively the mechanism through which HMGA2 regulates the EMT process and invasion in most cancers, including signaling pathways and the interacting RNA signaling axis. Thus, the elucidation of molecular mechanisms that underlie the effects of HMGA2 on cancer invasion and patient survival by mediating EMT may offer new therapeutic methods for preventing cancer progression.

Effect and Mechanism of lncRNA CERS6-AS1 on the Biological Behavior of Prostate Cancer Cell

Objective

To investigate the effect of long noncoding RNA (lncRNA) CERS6 antisense RNA1 (CERS6-AS1) on the biological behavior of prostate cancer cells DU145 and its mechanism.

Methods

RT-PCR was used to detect the relative level of CERS6-AS1 and miR-16-5p in prostate cancer tissues, adjacent tissues, prostate cancer cells DU145, and human normal prostate epithelial cells RWPE-1. DU145 cells were divided into control group, si-CERS6-AS1 group, si-NC group, miR-16-5p mimic group, miR-NC group, and si-CERS6-AS1+miR-16-5p inhibitor group. And CCK-8 method and colony formation test was applied to detect cell proliferation ability, flow cytometry was selected to calculate cell apoptosis, and scratch healing test was employed to assess cell migration ability. Western blot was determined to detect high mobility protein A2 (HMGA2) expression. RT-PCR and dual-luciferase reporter experiments were used to analyze the targeting relationship among CERS6-AS1, miR-16-5p, and HMGA2.

Results

Compared with the adjacent tissues, the relative level of CERS6-AS1 in prostate cancer tissue was increased (P < 0.05), and the relative level of miR-16-5p was decreased (P < 0.05). Compared with RWPE-1 cells, the relative level of CERS6-AS1 in DU145 cells was increased (P < 0.05), and the relative level of miR-16-5p was decreased (P < 0.05). Compared with the control group and the si-NC group, the HMGA2 protein expression, the colony formation number, and the scratch healing rate of DU145 cells in the si-CERS6-AS1 group and the miR-16-5p mimic group were reduced (P < 0.05), and the relative level of miR-16-5p and the proliferation inhibition rate and apoptosis were increased (P < 0.05). miR-16-5p is specifically bound to CERS6-AS1 and HMGA2, respectively. Compared with the si-CERS6-AS1 group, the HMGA2 protein expression, the colony formation number, and the scratch healing rate of DU145 cells in the si-CERS6-AS1+miR-16-5p inhibitor group were increased (P < 0.05), and the cell proliferation inhibition rate and apoptosis rate were reduced (P < 0.05).

Conclusion

Silencing CERS6-AS1 can inhibit the proliferation and migration of prostate cancer cell DU145 and induce cell apoptosis, the mechanism is related to the regulation of the miR-16-5p/HMGA2 axis.

circUBAP2 regulates osteosarcoma progression via the miR‑204‑3p/HMGA2 axis

Circular RNA (circRNA/circ)-ubiquitin associated protein 2 (UBAP2), a newly recognized circRNA, serves a functional role in several types of tumor, including ovarian cancer, colorectal cancer and osteosarcoma. However, the precise roles and molecular mechanism under-lying circUBAP2 in osteosarcoma (OS) are not completely understood. In the present study, the expression levels of circUBAP2, microRNA (miR)-204-3p and (HMGA2) were evaluated via reverse transcription-quantitative PCR in OS tissues and cells. OS cell proliferation, migration, invasion and apoptosis were assessed by performing Cell Counting Kit-8, Transwell and flow cytometry assays, respectively. HMGA2 protein expression levels were determined via western blot-ting. Dual-luciferase reporter assays were performed to verify the interaction between circUBAP2 and miR-204-3p, and between miR-204-3p and HMGA2. An RNA immunoprecipitation (RIP) assay was conducted to confirm the interaction between circUBAP2 and miR-204-3p. The results demonstrated that circUBAP2 expression was significantly upregulated in OS tissues and cell lines compared with para-cancerous tissues and hFOB1.19 cells, respectively. In addition, high circUBAP2 expression levels in patients with OS were associated with a lower survival rate compared with lower expression levels in patients with OS. The functional assays revealed that circUBAP2 knockdown significantly inhibited OS cell proliferation, migration and invasion, but increased OS cell apoptosis compared with the small interfering RNA-negative control (si-NC) group. The dual-luciferase reporter and RIP assay results confirmed that circUBAP2 bound to miR-204-3p. Moreover, miR-204-3p expression was significantly downregulated in OS tissues compared with paracancerous tissues, and miR-204-3p expression was negatively correlated with circUBAP2 expression in OS tissues. Collectively, the results demonstrated that miR-204-3p was associated with circUBAP2 knockdown-mediated inhibition of OS cell malignant behavior. Moreover, miR-204-3p was also identified as one of the direct targets of HMGA2. Collectively, the results indicated that compared with the si-NC group, circUBAP2 knockdown significantly inhibited OS cell malignant behavior by binding to miR-204-3p, which subsequently regulated HMGA2 expression. Therefore, the present study demonstrated that circUBAP2 expression was upregulated in OS, and circUBAP2 regulated OS cell malignant behavior via the miR-204-3p/HMGA2 axis.