Inhibition of ITCH Suppresses Proliferation and Induces Apoptosis of Lung Cancer Cells

Abstract

Background/Aims: The E3 ubiquitin ligase ITCH plays an important role in invasive and metastatic cancers. However, the role of ITCH in the progression of lung cancer has not been fully described. Methods: Real-time PCR was used to detect the expression of ITCH mRNA in the tumor tissues and paracarcinoma tissues from 32 patients with lung cancer. SiRNA was used to inhibit the expression of ITCH in two lung cancer cell lines, H1975 and Calu3 and the cell proliferation and apoptosis were measured by MTT and flow cytometric assay. In addition, to further investigate whether ITCH affected the apoptosis of cancer cells and its underlying mechanisms, the expression of important markers of apoptosis and invasion in lung cancer cells were detected by Western blot. Results: The study showed significant increments in the expression of ITCH in lung cancer tissues (p< 0.001). ITCH siRNA effectively inhibited the proliferation and invasion of the lung cancer cells and promoted cell apoptosis. Molecular analysis further showed significant reductions in the expression of Bcl2, MMP2, MMP9 and β-catenin and an increase in the expression of Bax and E-cadherin in the lung cancer cells with ITCH deficiency. Conclusions: Inhibition of ITCH might suppress lung cancer proliferation and invasion via regulation of MMPs, EMT and Bcl2/Bax signaling pathway.

Keywords

• Itch
• Lung cancer
• MMPs
• EMT
• Bcl2/Bax