Stromal-induced downregulation of miR-1247 promotes prostate cancer malignancy

Cancer progression is strictly dependent on the relationship between tumor cells and the surrounding stroma, which supports cancer malignancy promoting several crucial steps of tumor progression, including the execution of the epithelial to mesenchymal transition (EMT) associated with enhancement in cell invasion, resistance to both anoikis and chemotherapeutic treatments. Recently it has been highlighted the central role of microRNAs (miRNAs) as regulators of tumor progression. Notably, in several tumors a strong deregulation of miRNAs is observed, supporting proliferation, invasion, and metabolic reprogramming of tumor cells. Here we demonstrated that cancer-associated fibroblasts induce a downregulation of miR-1247 in prostate cancer (PCa) cells. We proved that miR-1247 repression is functional for the achievement of EMT and increased cell invasion as well as stemness traits. These phenomena contribute to promote the metastatic potential of PCa cells as demonstrated by increased lung colonization in in vivo experiments. Moreover, as a consequence of miR-1247 downregulation, we observed a correlated increased expression level of neuropilin-1, a miR-1247 target involved as a coreceptor in the epidermal growth factor receptor signaling. Taken together, our data highlight miR-1247 as a potential target for molecular therapies aimed to block the progression and diffusion of PCa.

Bioinformatic analysis of four miRNAs relevant to metastasis-regulated processes in endometrial carcinoma

BACKGROUND

The purpose of this study was to investigate the expression of different miRNAs in nonmetastatic and metastatic endometrial cancer Existing evidence indicates that there are many factors affecting the metastasis of endometrial cancer, and miRNAs play an unique role in many processes of endometiral cancer.

MATERIALS AND METHODS

miRNA sequences were downloaded from The Cancer Genome Atlas Project database, and Bioinformatics technique was used to deal with those data.

RESULTS

We elucidated the relation between differentially expressed miRNAs and clinical information for a total of 260 tumor tissues and 22 tumor tissues that had metastasized. We used the threshold of P <0.05| log 2 FC | >1.2 to identify potential miRNAs. Four differentially expressed miRNAs were identified in nonmetastatic and metastatic endometrial cancers. Further differential analysis of metastatic tissue revealed that miR-1247 is associated with metastasis of endometrial cancer to the lung, and miR-3200 is associated with the clinical stage of endometrial cancer. A functional enrichment analysis showed that the four miRNAs may be involved in multiple pathways of cancer, including the Wnt, NOTCH, and TGF-β signaling pathways and signaling pathways regulating pluripotency of stem cells. Protein-protein interaction analysis showed that PAK6, SNAP25, MAN1A1, MYB, ZBTB4, UST, ALDH1A3, and NRP2 are hub genes of relevant miRNAs in endometrial cancers.

CONCLUSION

The current study indicates that these four miRNAs may be related to molecular markers of metastasis of endometrial cancer.

MicroRNA-1247 inhibits cell proliferation by directly targeting ZNF346 in childhood neuroblastoma

BACKGROUND

Neuroblastoma (NB) represents the most common extracranial solid tumor in children. Accumulating evidence shows that microRNAs (miRs) play an important role in the carcinogenesis of NB. Here, we investigated the biological function of miR-1247 in NB in vitro.

METHODS/RESULTS

We found miR-1247 was downregulated in NB tissues and cells using quantitative PCR analysis. Gain- and loss-of-function studies demonstrated that miR-1247 significantly suppressed cell proliferation and induced cell cycle G0/G1 phase arrest and cell apoptosis of NB cells in vitro by using MTT, colony formation assay and Flow cytometry analysis. Luciferase assay suggested ZNF346 was the target of miR-1247 and its expression could be downregulated by miR-1247 overexpression using Western blotting. Furthermore, downregulation of ZNF346 by siRNA performed similar effects with overexpression of miR-1247 in NB cells.

CONCLUSIONS

Our findings suggested miR-1247 directly targeted to repress ZNF346 expression, thus suppressing the progression of NB, which might be a novel therapeutic target against NB.

Epigenetically altered miR-1247 functions as a tumor suppressor in pancreatic cancer

Altered expression of microRNAs has been strongly implicated in human cancers, and growing evidence is emerging that a number of miRNAs are downregulated in cancer associated with CpG island hypermethylation. Although pancreatic cancer is one of the most malignant human cancers, the roles of miRNAs underlying the tumorigenesis of pancreatic cancer are still poorly understood. In the present study, we explored the molecular functional role of microRNA-1247 as tumor suppressor associated with epigenetic alteration in pancreatic cancer. CpG islands methylation of miR-1247 is frequently observed in various pancreatic cancer cell lines and in primary pancreatic tumors, but not in normal pancreatic tissue. Ectopic expression of miR-1247 in five pancreatic cancer cell lines results in suppressing of cell growth, proliferation, migration, and invasion in vitro and tumorigenicity of pancreatic cancer cells in vivo. Interestingly, we found one putative target gene of miR-1247, regulator of chromosome condensation 2 (RCC2), harbored miR-1247 target sequences in the 3′ UTR of its mRNA. In functional studies in vitro to understand the interaction between miR-1247 and RCC2, decreasing of RCC2 gene expression by miR-1247 was observed by immunoblotting and immunohistochemistry at both mRNA and protein levels. Moreover, luciferase reporter assay confirmed that RCC2 was a direct target of miR-1247. Taken together, our data suggest that CpG island hypermethylation of miR-1247 is responsible for its downregulation in pancreatic cancer, and ectopic expression of miR-1247 functions as a potential tumor suppressor targeting RCC2 in pancreatic cancer cells.

MiRNA profile of osteosarcoma with CD117 and stro-1 expression: miR-1247 functions as an onco-miRNA by targeting MAP3K9

microRNAs (miRNA) are regulators of gene expression, but little is known about miRNA expression profiles in stem cells of osteosarcoma (OS). C117 and Stro-1 are known stem cell markers of OS. In the study, CD117 and stro-1 positive (CD117(+)stro-1(+)) and CD117 and stro-1 negative (CD117(-)stro-1(-)) cells were isolated from MG63 cells CD117(+)stro-1(+) cells showed more metastatic ability and stem cell formation rate than CD117(-)stro-1(-) ones. To find the difference between CD117(+)stro-1(+) and CD117(-)stro-1(-) cells, the miRNA expression profile was examined using DNA microarray. MicroRNAs were differentially expressed in osteosarcoma cells with CD117(+)stro-1(+) and CD117(-)stro-1(-). The significant miRNAs included miR-15a, miR-302a, miR-423-5p, miR-1247, miR-1243 and others, which were confirmed by real time RT-PCR. The significant down-regulated miR-1247 was confirmed that was a potential tumor suppressor by targeting MAP3K9. Our results indicated that dysregulation of miRNAs is involved in osteosarcoma and miR-1247 plays an important role in progression of osteosarcoma.