Role and mechanism of KIAA1429 in regulating cellular ferroptosis and radioresistance in colorectal cancer.

Colorectal cancer (CRC) is one of the most common non-cutaneous malignancies, causing significant mortality and a substantial burden. This study aims to explore the role of KIAA1429 (also known as vir-like m6A methyltransferase associated [VIRMA]) protein in the radioresistance of CRC. CRC cells and a radioresistant cell line were cultured, and KIAA1429 expression was detected. After the down-regulation of KIAA1429, its effect on the radioresistance and ferroptosis of cancer cells was analyzed. The role of ferroptosis in radioresistance was verified. The binding relationship among long non-coding RNA endogenous Bornavirus-like nucleoprotein 3, pseudogene (lncRNA EBLN3P), microRNA (miR)-153-3p, and KIAA1429 was analyzed. KIAA1429 and lncRNA EBLN3P were highly expressed in CRC, while miR-153-3p was poorly expressed. KIAA1429 and lncRNA EBLN3P were further increased/decreased in the radioresistant cells. KIAA1429 knockdown decreased the survival rate of the radioresistant cell line after X-ray irradiation and increased gamma H2A histone family member X (γ-H2AX), ferroptosis, and oxidative stress. A ferroptosis inhibitor alleviated the inhibitory effect of KIAA1429 knockdown on radioresistance. KIAA1429-mediated m6A modification up-regulated lncRNA EBLN3P, and lncRNA EBLN3P increased KIAA1429 by competitively binding to miR-153-3p. miR-153-3p silencing or lncRNA EBLN3P overexpression attenuated the promotion of ferroptosis and the inhibition of radioresistance induced by KIAA1429 knockdown. Overall, KIAA1429-mediated m6A modification up-regulated lncRNA EBLN3P expression, and lncRNA EBLN3P increased KIAA1429 expression by competitively binding to miR-153-3p, thus reducing ferroptosis and increasing the radioresistance of CRC.