Carfilzomib suppressed LDHA-mediated metabolic reprogramming by targeting ATF3 in esophageal squamous cell carcinoma

Carfilzomib, a second-generation proteasome inhibitor, has been approved as a treatment for relapsed and/or refractory multiple myeloma. Nevertheless, the molecular mechanism by which Carfilzomib inhibits esophageal squamous cell carcinoma (ESCC) progression largely remains to be determined. In the present study, we found that Carfilzomib demonstrated potent anti-tumor activity against esophageal squamous cell carcinoma both in vitro and in vivo. Mechanistically, carfilzomib triggers mitochondrial apoptosis and reprograms cellular metabolism in ESCC cells. Moreover, it has been identified that activating transcription factor 3 (ATF3) plays a crucial cellular target role in ESCC cells treated with Carfilzomib. Overexpression of ATF3 effectively antagonized the effects of carfilzomib on ESCC cell proliferation, apoptosis, and metabolic reprogramming. Furthermore, the ATF3 protein is specifically bound to lactate dehydrogenase A (LDHA) to effectively suppress LDHA-mediated metabolic reprogramming in response to carfilzomib treatment. Research conducted in xenograft models demonstrates that ATF3 mediates the anti-tumor activity of Carfilzomib. The examination of human esophageal squamous cell carcinoma indicated that ATF3 and LDHA have the potential to function as innovative targets for therapeutic intervention in the treatment of ESCC. Our findings demonstrate the novel function of Carfilzomib in modulating ESCC metabolism and progression, highlighting the potential of Carfilzomib as a promising therapeutic agent for the treatment of ESCC.