HOTAIR induces the down regulation of miR-200 family members including miR-200a, 200b, 200c in gastric cancer cell lines

Gastric cancer (GC) is the fourth most common human malignancy and the second reason for cancer morbidity worldwide. Long non-coding RNA HOTAIR has recently emerged as a promoter of metastasis in various cancer types, including GC, through EMT process. However, the exact mechanism of HOTAIR in promoting of EMT has been unknown. Aberrant expression of the miR-200 family has been also linked to the occurrence and development of various types of malignant tumors. This study investigates the correlation between the HOTAIR and miR-200 family genes expression patterns in GC cell lines. We investigated the miR-200 and HOTAIR due to their common molecular features in EMT process.

We transfected the AGS and MKN45 cell lines with siRNA targeting the HOTAIR along with a negative control. We analyzed the effect of HOTAIR knock down on cell viability as well as expression of miR-200 family members including miR-200a, 200b, and 200c in cell lines using qRT-PCR. Statistical analysis was performed to find the potential correlation between the expression level of HOTAIR and miRs.

Our results showed significantly increased miR-200 family expression level in transfected AGS and MKN45 GC cells (Fold changes>2, P-value <0.001). Moreover, we observed a negative correlation between HOTAIR and miR-200 expression levels in GC cell lines (P-value<0.05).

Our findings showed a significant association between miR-200 family and HOTAIR expression levels in GC cell lines. Taken together, the HOTAIR-miR-200 axis seems to play a vital role in human GC, suggesting a potential therapeutic target in future GC treatment.