Journal of International Oncology ›› 2026, Vol. 53 ›› Issue (5): 268-275.doi: 10.3760/cma.j.cn371439-20250712-00044

• Original Article • Previous Articles     Next Articles

Effect and mechanism of IFITM1 gene silencing in mitigating cisplatin resistance in small cell lung cancer cells

Qian Haihong(), Wang Xuemei, Liu Siyan, Wang Hua, Zhang Hengjiao, Yang Donghai, Sun Qiong, Zhao Danye   

  1. Tumor CenterPeople's Hospital of Yuxi City, Yunnan Province/Sixth Affiliated Hospital of Kunming Medical UniversityYuxi 653100, China
  • Received:2025-07-12 Online:2026-05-08 Published:2026-05-06
  • Contact: Qian Haihong E-mail:15987717153@163.com
  • Supported by:
    Science and Technology Plan of Yunnan Provincial Department of Science and Technology(202101AY070001-197)

Abstract:

Objective To investigate the effect of targeted silencing of interferon-induced transmembrane protein 1 (IFITM1) on cisplatin resistance in small cell lung cancer (SCLC) cells and to explore the underlying mechanisms. Methods Tumor tissue samples of 24 patients with SCLC who received chemotherapy with cisplatin regimen at the Tumor Center of People's Hospital of Yuxi City in Yunnan Province from January 2019 to December 2020 were collected and divided into the resistant group (n=12) and the non-resistant group (n=12). The mRNA and protein expression levels of IFITM1 were detected by real-time quantitative PCR and enzyme-linked immunosorbent assay, respectively. After targeted silencing of IFITM1 in the cisplatin-resistant SCLC cell lines NCI-H82/cisplatin and SHP-77/cisplatin cells, changes in the IC50 of cisplatin were evaluated. IFITM1-silenced cisplatin-resistant cells were treated with low-dose cisplatin and divided into cisplatin-resistant cell group, IFITM1-silencing negative control group, IFITM1-silencing group, gradient cisplatin treatment group, IFITM1-silencing+gradient cisplatin treatment group, cisplatin (10 μmol/L) treatment group, IFITM1-silencing negative control+cisplatin(10 μmol/L) treatment group, IFITM1-silencing+cisplatin (10 μmol/L) treatment group. Cell proliferation was assessed using the CCK-8 assay, cell invasion was evaluated using the Transwell assay, cell apoptosis was detected by TUNEL staining, and protein expression levels were analyzed by Western blotting. Results The expression levels of IFITM1 mRNA and protein in the tissues of SCLC patients in the resistant group were both higher than those in the non-resistant group (both P<0.05). IC50 analysis results showed that the IC50 values of cisplatin in NCI-H82/cisplatin cells were (43.12±8.00), (41.48±10.57), and (14.82±4.78)μmol/L in the cisplatin-resistant cell group, IFITM1-silencing negative control group, and IFITM1-silencing group, respectively, with a statistically significant difference (F=11.44, P=0.009), and the IC50 values in the IFITM1-silencing group were lower than those in the cisplatin-resistant cell group and IFITM1-silencing negative control group (both P<0.05). CCK-8 assay results showed that, the proliferation activities of NCI-H82/cisplatin cells in the cisplatin-resistant cell group, cisplatin treatment group, IFITM1-silencing negative control+cisplatin treatment group, and IFITM1-silencing+cisplatin treatment group were 1.35±0.18, 1.15±0.17, 1.06±0.18, and 0.52±0.08, respectively, with a statistically significant difference (F=15.17, P=0.001), and proliferation activity in the IFITM1-silencing+cisplatin treatment group was significantly lower than that in the cisplatin-resistant group, cisplatin treatment group and IFITM1-silencing negative control+cisplatin treatment group (all P<0.05). Transwell assay results indicated that, the numbers of invading NCI-H82/cisplatin cells in the cisplatin-resistant cell group, cisplatin treatment group, IFITM1-silencing negative control+cisplatin treatment group, and IFITM1-silencing+cisplatin treatment group were 1 380.00±166.43, 1 259.33±198.01, 1 143.00±169.14, and 563.00±127.39, respectively, with a statistically significant difference (F=15.11, P=0.001), and the numbers of invasion were significantly lower in the IFITM1-silencing+cisplatin treatment group than those in the cisplatin-resistant cell group, cisplatin treatment group and IFITM1-silencing negative control+cisplatin treatment group (all P<0.05). TUNEL staining results showed that, apoptosis rates of NCI-H82/cisplatin cells in the above four groups were (12.00±2.91)%, (15.83±3.50)%, (16.37±3.59)%, and (42.46±4.95)%, respectively, with a statistically significant difference (F=40.45, P<0.001), and the apoptosis rate of the IFITM1-silencing+cisplatin treatment group was significantly higher than that of the cisplatin-resistant cell group, cisplatin treatment group and IFITM1-silencing negative control+cisplatin treatment group (all P<0.05). The above experimental results for SHP-77/cisplatin cells were consistent with those of NCI-H82/cisplatin cells. The results of Western blotting showed that there were statistically significant differences in the protein expression levels of IFITM1, p-β-catenin, ABCB1, and ABCG2 among the NCI-H82/cisplatin resistant cell group, the IFITM1-silencing negative control group, and the IFITM1-silencing group (all P<0.05). Compared with the cisplatin-resistant cell group and the IFITM1-silencing negative control group, the IFITM1-silencing group exhibited significantly higher p-β-catenin expression and significantly lower IFITM1, ABCB1, and ABCG2 expression levels (all P<0.05). Conclusions IFITM1 plays a promotive role in cisplatin resistance of SCLC cells. Targeted silencing of IFITM1 effectively reduces cisplatin resistance by inhibiting the Wnt signaling pathway.

Key words: Small cell lung carcinoma, Cisplatin, Drug resistance, neoplasm, Wnt signaling pathway, Interferon-induced transmembrane protein 1