SFTA2 reduced colorectal cancer ferroptosis promoting metastasis through regulating EMT transition by degradation of Nrf2.

Colon cancer is a common malignancy of the digestive system, tumor disease, and its prevalence in China shows a consistently increasing trend. This study aimed to investigate the role of surfactant associated 2 (SFTA2) in colorectal cancer (CRC) and its molecular mechanism involving ferroptosis. Colon cancer tissues were obtained from patients and normal volunteers from our hospital, and a mouse model of CRC was established using azoxymethane (AOM)/dextran sulfate sodium (DSS) induction. SFTA2 expression was significantly up-regulated at both the messenger RNA (mRNA) and protein levels in CRC tissues and cell lines. Patients with high SFTA2 expression exhibited a shorter survival time compared to those with low SFTA2 expression. SFTA2 was found to be expressed in cancer cells of CRC patients, associated with key signaling molecules. Sh-SFTA2 reduced cancer proliferation in the mice model of CRC. SFTA2 up-regulation promoted cell proliferation of CRC. SFTA2 down-regulation promoted cell proliferation of CRC. SFTA2 up-regulation reduced oxidative stress and ferroptosis of CRC. SFTA2 up-regulation reduced ferroptosis of CRC through mitochondrial damage-tricarboxylic acid cycle (TAC). SFTA2 down-regulation suppressed nuclear factor erythroid 2-related factor 2 (Nrf2) expression in the model of CRC. SFTA2 up-regulation reduced Nrf2 ubiquitination in the model of CRC. Nrf2 reversed the effects of si-SFTA2 on ferroptosis of CRC. Furthermore, SFTA2 down-regulation suppressed Nrf2 expression, while SFTA2 up-regulation decreased Nrf2 ubiquitination in the CRC model. Nrf2 was shown to reverse the pro-ferroptotic effects of si-SFTA2, indicating that SFTA2 activates the Nrf2 pathway by inhibiting its ubiquitination, thereby reducing mitochondrial damage and TCA cycle disruption in CRC. SFTA2 induced the Nrf2 pathway to reduce mitochondrial damage-TAC of the CRC model through the inhibition of Nrf2 ubiquitination. SFTA2 is thus a potentiallyeffective therapeutic strategy for patients with CRC or other cancers.