Impact of connexin 43 coupling on survival and migration of multiple myeloma cells

Cancer-associated fibroblast-derived exosome microRNA-21 promotes angiogenesis in multiple myeloma

Multiple myeloma (MM) is the second most common hematological malignancy, and angiogenesis determines its progression. In the tumor microenvironment, normal fibroblasts (NFs) are transformed into cancer-associated fibroblasts (CAFs), which can promote angiogenesis. Microribonucleic acid-21 (miR-21) is highly expressed in various tumors. However, research on the relationship between tumor angiogenesis and miR-21 is rare. We analyzed the relationship between miR-21, CAFs, and angiogenesis in MM. NFs and CAFs were isolated from the bone marrow fluids of patients with dystrophic anemia and newly-diagnosed MM. Co-culturing of CAF exosomes with multiple myeloma endothelial cells (MMECs) showed that CAF exosomes were able to enter MMECs in a time-dependent manner and initiate angiogenesis by promoting proliferation, migration, and tubulogenesis. We found that miR-21 was abundant in CAF exosomes, entering MMECs and regulating angiogenesis in MM. By transfecting NFs with mimic NC, miR-21 mimic, inhibitor NC, and miR-21 inhibitor, we found that miR-21 significantly increased the expression of alpha-smooth muscle actin and fibroblast activation protein in NFs. Our results showed that miR-21 can transform NFs into CAFs, and that CAF exosomes promote angiogenesis by carrying miR-21 into MMECs. Therefore, CAF-derived exosomal miR-21 may serve as a novel diagnostic biomarker and therapeutic target for MM.

Long non-coding RNA SNHG1 promotes cell proliferation and invasion of hepatocellular carcinoma by acting as a molecular sponge to modulate miR-195

INTRODUCTION

Although long non-coding RNA SNHG1 (lncRNA SNHG1) action on cell proliferation and invasion of hepatocellular carcinoma (HCC) cells has been reported, the effects of lncRNA SNHG1 on migration of HCC cells and the mechanisms are still unclear. The present study aimed to investigate the influence of lncRNA SNHG1 on metastasis in HCC cells and the possible mechanisms underlying this phenotype.

MATERIAL AND METHODS

Expression of lncRNA SNHG1 and miR-195 was determined using qRT-PCR in both HCC cell lines Huh7 and HepG2. Si-RNA was used to silence SNHG1 and miR-195 inhibitor was used to inhibit expression of miR-195. Luciferase reporter assay was conducted to confirm whether miR-195 was the direct binding target of SNHG1.

RESULTS

lncRNA SNHG1 was significantly up-regulated and miR-195 was significantly down-regulated in HCC cell lines. When transfected with si-SNHG1, migration and invasion of HCC cells, as well as expression of astrocyte elevated gene 1 (AEG-1) protein, were significantly inhibited compared with the control cells. Results of dual luciferase reporter assay showed that lncRNA SNHG1 acted as an endogenous sponge of miR-195. On the other hand, the expression of miR-195 in tumor tissue was much lower than that of miR-195 in the corresponding normal tissue. Furthermore, the correlation analysis showed a strong negative relationship between lncRNA SNHG1 and miR-195 expression in HCC tissues.

CONCLUSIONS

SNHG1 may promote cell invasion and migration in HCC cells by sponging miR-195. These results can provide deeper understanding of SNHG1 in hepatocellular cancer and give new potential targets for treatment of HCC.

MicroRNA-331-3p inhibits proliferation and metastasis of ovarian cancer by targeting RCC2

INTRODUCTION

Epithelial ovarian carcinoma (EOC) is one of the most lethal gynecologic malignancies, with a poor 5-year survival rate. Numerous studies have shown that microRNAs participate in the malignant behavior of ovarian cancer cells by directly targeting multiple oncogenes or tumor suppressor genes.

MATERIAL AND METHODS

Reverse transcription-PCR was used to determine the level of miR-331-3p in EOC. Cells proliferation was measured with the Cell Counting Kit-8. Cell mobility were measured by wound-healing assay. Cell migration and invasion were measured by transwell assay. Luciferase assays were used to demonstrate that RCC2 was a directed target of miR-331-3p in EOC. Western blots were used to measure the protein expression.

RESULTS

We found that the expression of microRNA-331-3p (miR-331-3p) in ovarian cancer cell lines is reduced (p < 0.01), and an increase of expression of miR-331-3p in ovarian cancer cells significantly inhibits cell proliferation (p < 0.001). Transwell and wound-healing assays showed that miR-331-3p inhibits the cell motility of ovarian cancer cells (p < 0.001). Regulator of chromosome condensation 2 (RCC2) was predicted to be a novel target for miR-331-3p. Our luciferase activity assay confirmed that RCC2 is directly targeted by miR-331-3p. RCC2 was negatively regulated by miR-331-3p (p < 0.001), and overexpression of RCC2 could restore the malignant behaviors of ovarian cancer cells, which was suppressed by miR-331-3p.

CONCLUSIONS

These data indicate that miR-331-3p can inhibit proliferation, migration, and invasion of ovarian cancer cells via directly targeting RCC2. Our study provides potential therapeutic targets for the treatment of ovarian cancer.