ABSTRACT
@#BACKGROUND: Exosomes and exosomal microRNAs have been implicated in tumor occurrence and metastasis. Our previous study showed that microRNA-761 (miR-761) is overexpressed in hepatocellular carcinoma (HCC) tissues and that its inhibition affects mitochondrial function and inhibits HCC metastasis. The mechanism by which exosomal miR-761 modulates the tumor microenvironment has not been elucidated. METHODS: Exosomal miR-761 was detected in six cell lines. Cell counting kit-8 (CCK-8) and transwell migration assays were performed to determine the function of exosomal miR-761 in HCC cells. The luciferase reporter assay was used to analyze miR-761 target genes in normal fibroblasts (NFs). The inhibitors AZD1480 and C188-9 were employed to determine the role of the Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) signaling pathway in the transformation of cancer-associated fibroblasts (CAFs). RESULTS: In this study, we characterized the mechanism by which miR-761 reprogrammed the tumor microenvironment. We found that HCC-derived exosomal miR-761 was taken up by NFs. Moreover, HCC exosomes affected the tumor microenvironment by activating NFs via suppressor of cytokine signaling 2 (SOCS2) and the JAK2/STAT3 signaling pathway. CONCLUSIONS: These results demonstrated that exosomal miR-761 modulated the tumor microenvironment via SOCS2/JAK2/STAT3 pathway-dependent activation of CAFs. Our findings may inspire new strategies for HCC prevention and therapy.
ABSTRACT
<p><b>OBJECTIVE</b>To study the transfection of pancreatic cancer cells BxPC-3 with recombinant plasmid pSilencer4.1-CMV neo-hTERT-siRNA and its silencing effects.</p><p><b>METHODS</b>Pancreatic cancer cells BxPC-3 transfected with recombinant plasmid pSilencer4.1-CMV neo-hTERT-siRNA were selected as target and divided into five groups: (1) T1 group (pSilencer4.1CMV neo-hTERT1-siRNA), (2) T2 group (pSilencer4.1CMV neo-hTERT2-siRNA), (3) Lipofectamine (Lipofectamine), (4) mismatch group(pSilence4.1CMV, as negative control), (5) cell control group(without transfection). The expression of hTERT mRNA was detected by RT-PCR. The viability of cells was measured by MTT method. The cell cycle and cell apoptosis was measured by flow cytometry. The expression of telomerase protein was measured by Western blot.</p><p><b>RESULTS</b>Compared with Lipofectamine group, negative control group and cell control group, the expression of hTERT-mRNA and telomerase protein in cells was downregulated significantly(P<0.05), the viability of BxPC-3 cells was decreased significantly (P<0.05), the ratio of cells in G0/G1 stage was increased, the ratio of cells in S stage and G2/M stage was decreased, and the ratio of apoptotic cells was increased significantly in T1 group and T2 group.</p><p><b>CONCLUSION</b>Recombinant plasmid T1 and T2 can downregulate the expression of hTERT mRNA and telomerase protein in BxPC-3 cells , and has good RNAi silencing effects. T1 and T2 can also inhibit the growth of BxPC-3 cells, block the cell cycle, promote the apoptosis of cells, and has anti-pancreatic cancer effects in vitro.</p>