MiR-191-5p inhibits KLF6 to promote epithelial-mesenchymal transition in breast cancer

Extracellular vesicles from adipose-derived mesenchymal stem cells promote colony formation ability and EMT of corneal limbal epithelial cells

Corneal diseases are a leading cause of visual impairment, and their treatment remains challenging. Corneal epithelial stem cells exist in the limbus, the peripheral region of the cornea, and play an important role in corneal regeneration. Here, we evaluated the effects of extracellular vesicles from human adipose-derived mesenchymal stem cells (AdMSC-EVs) on limbal epithelial cells (LECs). Colony formation assays showed that the colony-forming efficiency of LECs significantly increased in the presence of AdMSC-EVs. We next demonstrated that AdMSC-EVs accelerated the migration of LECs in a scratch assay, whereas the proliferation of LECs was decreased by AdMSC-EVs in the cell proliferation assay. RNA sequencing analysis of LECs indicated that AdMSC-EVs maintained their stem cell properties and improved epithelial-mesenchymal transition (EMT). Furthermore, after identifying the six most abundant microRNAs (miRNAs) in AdMSC-EVs, LEC transfection with miRNA mimics indicated that miR-25, miR-191, and miR-335 were the most probable miRNA factors within AdMSC-EVs at improving colony formation ability and EMT. Taken together, our findings indicated that AdMSC-EVs enhanced the colony formation ability and EMT of LECs, and the effects of AdMSC-EVs were in-part mediated by the miRNAs within the AdMSC-EVs.

Upregulation of vesicle-associated membrane protein 7 in breast cancer tissues

BACKGROUND

Vesicle-associated membrane protein 7 (VAMP7) plays oncogenic roles in cancers. However, its clinical significance in breast cancer (BC) tissues remains unknown.

OBJECTIVE

To elucidate the clinical implications of VAMP7, as well as its involvement in the tumor microenvironment and molecular pathways of breast cancer.

METHODS

BC (n=100) and non-cancerous breast tissues (n= 100) were collected for an immunohistochemical experiment (1:200). The protein expression level of VAMP7 was determined by using a semi-quantitative scoring method. High-throughput RNA-sequencing data of BC tissues were analyzed to confirm the mRNA expression trend of VAMP7. Additionally, the largest BC prognosis cohort data were collected to mine the potential impact VAMP7 has on BC progression. The association between VAMP7 and the microenvironment of BC was evaluated by using a CIBERSORT algorithm. Moreover, we explored the co-expressed molecular mechanisms of VAMP7 in BC by calculating Pearson correlation coefficients and overexpressed genes. Finally, the biological mechanism underlying the relationship between VAMP7 and the key pathways was also explored using gene set enrichment analysis (GSEA). Potential therapeutic strategies were predicted targeting VAMP7.

RESULTS

VAMP7 protein was significantly over-expressed in BC tissue than that in controls (p< 0.001). Compared with 459 normal breast tissues and 113 non-cancerous breast tissues, the expression level of VAMP7 mRNA was significantly increased in 1111 BC tissues. CD4+T cells, macrophages, and naïve B cells had a higher infiltration rate in BC tissues with high VAMP7 expression, while regulatory T cells and CD8+T cells had a lower infiltration rate. Over-expressed VAMP7 was associated with macrophages activation and transition from M1 to M2 polarization. Upregulated VAMP7 could predicted poorer OS, DMFS, PPS, and RFS outcomes. Upregulated VAMP7 co-expressed genes were significantly enriched in the cell cycle checkpoints. GSEA confirmed that over-expressed VAMP7 are markedly associated with functional enrichment in cell cycle related categories, including mitotic spindle, G2M checkpoint, and E2F targets. KU-55933 was predicted as a putative therapeutic drug for BC targeting VAMP7.

CONCLUSIONS

VAMP7 was upregulated in BC tissue and correlated with poor prognosis of BC patients. VAMP7 may promote BC progression by targeting the cell cycle pathway.