[Cited FineTest Protein] Current Research on Non Small Cell Lung Cancer Treatment

FineTest recombinant protein contributes to the research on non small cell lung cancer treatment. The western blot is designed to measure GPX4 in NSCLC cells.

Publication Details
Article Title: Timosaponin AIII promotes non-small-cell lung cancer ferroptosis through targeting and facilitating HSP90 mediated GPX4 ubiquitination and degradation
Journal Title: International Journal of Biological Sciences
DOI: 10.7150/ijbs.77979
IF: 10.75

Abstract: Timosaponin AIII (Tim-AIII), a steroid saponin, exhibits strong anticancer activity in a variety of cancers, especially breast cancer and liver cancer. However, the underlying mechanism of the effects of Tim-AIII-mediated anti-lung cancer effects remain obscure. In this study, we showed that Tim-AIII suppressed cell proliferation and migration, induced G2/M phase arrest and ultimately triggered cell death of non-small cell lung cancer (NSCLC) cell lines accompanied by the release of reactive oxygen species (ROS) and iron accumulation, malondialdehyde (MDA) production, and glutathione (GSH) depletion. Interestingly, we found that Tim-AIII-mediated cell death was reversed by ferroptosis inhibitor ferrostatin-1 (Fer-1). Meanwhile, the heat shock protein 90 (HSP90) was predicted and verified as the direct binding target of Tim-AIII by SwissTargetPrediction (STP) and surface plasmon resonance (SPR) assay. Further study showed that Tim-AIII promoted HSP90 expression and Tim-AIII induced cell death was blocked by the HSP90 inhibitor tanespimycin, indicating that HSP90 was the main target of Tim-AIII to further trigger intracellular events. Mechanical analysis revealed that the Tim-AIII-HSP90 complex further targeted and degraded glutathione peroxidase 4 (GPX4), and promoted the ubiquitination of GPX4, as shown by an immunoprecipitation, degradation and in vitro ubiquitination assay. In addition, Tim-AIII inhibited cell proliferation, induced cell death, led to ROS and iron accumulation, MDA production, GSH depletion, as well as GPX4 ubiquitination and degradation, were markedly abrogated when HSP90 was knockdown by HSP90-shRNA transfection. Importantly, Tim-AIII also showed a strong capacity of preventing tumor growth by promoting ferroptosis in a subcutaneous xenograft tumor model, whether C57BL/6J or BALB/c-nu/nu nude mice. Together, HSP90 was identified as a new target of Tim-AIII. Tim-AIII, by binding and forming a complex with HSP90, further targeted and degraded GPX4, ultimately induced ferroptosis in NSCLC. These findings provided solid evidence that Tim-AIII can serve as a potential candidate for NSCLC treatment.

Keywords: Non-small Cell Lung Cancer Treatment, Timosaponin AIII, Heat Shock Protein 90, Glutathione Peroxidase 4, Ferroptosis

Western Blot

Validated Image

Figure Source:  Int J Biol Sci 2023; 19(5):1471-1489. doi:10.7150/ijbs.77979.

Figure 5A: The protein expression of HSP90 and GPX4 was examined by WB after treatment with Tim-AIII with or without tanespimycin for 48 h in H1299 and A549 cells.