By Sameh Saber, Alexandru Hasan, Simona Cavalu et al.
Sorafenib, a multikinase inhibitor, is a first-line treatment for advanced hepatocellular carcinoma, but its longterm effectiveness is limited by the emergence of resistance mechanisms. HSP90 plays a critical role in conferring resistance to sorafenib in HepG2 cells under hypoxic
conditions and N-Nitrosodiethylamine-exposed mice. To augment the effects of sorafenib, we investigated the use of ganetespib, an HSP90 inhibitor. We observed a significant negative correlation between LAMP2 and MLKL. Combining ganetespib with sorafenib showed a synergistic cytotoxic effect and resulted in the accumulation of p62 and inhibition of macroautophagy. Copyright Sameh Saber, Alexandru Hasan, Simona Cavalu et al.
The proper transportation of proteins across the lysosomal membrane
in the CMA process is dependent on essential components,
including HSP90 and LAMP2. Our study indicates that under hypoxic
conditions, there is a significant upregulation of HSP90 and LAMP2
expression. Our findings suggest that MLKL, which is the mediator of
necroptosis, can be degraded through the CMA pathway under hypoxia.
Furthermore, our preclinical data show that HSP90 plays a critical role
in conferring resistance to SFB under hypoxia by inhibiting necroptosis.
Combining GTSB with SFB may offer a promising therapy for HCC. Copyright Sameh Saber, Alexandru Hasan, Simona Cavalu et al.
Full text available at: https://doi.org/10.1016/j.biopha.2023.114918