Down-regulation of YAP prevents smoking- and alcohol-induced carcinogenesis of esophageal paracancerous tissue by promoting cellular pyroptosis

Paracancerous tissues (PCTs) were previously considered benign regions, but recent findings reveal genomic instability in these areas. Smoking and alcohol consumption are closely associated with esophageal cancer (EC) development. This study explored the interplay between the Hippo pathway and pyroptosis in EC, PCTs, and distal normal tissues (DNTs). We used molecular epidemiological methods to analyze the effects of smoking and alcohol on these pathways. We found that key genes in both pathways were more altered in smokers and/or drinkers compared to non-smokers and non-drinkers. Additionally, we observed changes in some genes and proteins in PCTs, while the Hippo pathway and pyroptosis had not yet been influenced. We applied 4.0% alcohol combined with various concentrations of cigarette smoke extract (CSE) to PCTs cultured in vitro to observe carcinogenesis and changes in these pathways. Verteporfin, as an inhibitor of YAP, was also used in vitro culture experiments to observe its effects on cellular carcinogenesis. Among 56 EC patients, 41 had a history of smoking and/or alcohol consumption in this study. Compared to DNTs, Hippo pathway genes (Lats1, Yap, and Taz) and pyroptosis genes (Nlrp3, Asc, Gsdmd, and Caspase-1) were altered in 49 EC tissues, while changes of Lats1, Nlrp3, and Asc were observed in 47 PCTs. Additionally, 4.0% alcohol combined with 3.2%, 4.0%, and 5.8% CSE, respectively, not only induced cellular heterogeneity and even cancerous transformation, but also suppressed the Hippo pathway and pyroptosis in the PCTs cultured in vitro. Furthermore, in vitro, 9 μM verteporfin inhibited cellular heterogeneity/carcinogenesis in PCTs induced by 4.0% alcohol combined with 5.8% CSE through inhibiting YAP and promoting pyroptosis. It is speculated that the downregulation of YAP could prevent smoking- and alcohol-induced carcinogenesis in esophageal PCTs by promoting pyroptosis, which may offer new insights for the treatment of esophageal squamous carcinoma.