Summary
Type 2 Diabetes (T2D) and male gender are associated with hepatocellular carcinoma (HCC) development. We demonstrate that heterozygous deletion of the Ncoa5 gene causes spontaneous development of HCC, exclusively in male mice. Tumor development is preceded by increased IL-6 expression, early-onset glucose intolerance, and progressive steatosis and dysplasia in livers. Blockading IL-6 overexpression averts glucose intolerance and partially deters HCC development. Moreover, reduced NCOA5 expression is associated with a fraction of human HCCs and HCCs with comorbid T2D. These findings suggest that NCOA5 is a haplo-insufficient tumor suppressor, and NCOA5 deficiency increases susceptibility to both glucose intolerance and HCC, partially by increasing IL-6 expression. Thus, our findings open additional avenues for developing therapeutic approaches to combat these diseases.
Lung adenocarcinoma, the most common type of human non-small cell lung cancer (NSCLC), frequently overexpresses EGFR. However, the mechanisms underlying EGFR overexpression are not completely understood. Recent studies have identified that decreased expression of TIP30 is associated with the metastasis of human NSCLCs, but a causative relationship between TIP30 deficiency and NSCLC development remains unclear. We show here that Tip30 deletion leads to spontaneous development of lung adenomas and adenocarcinomas in mice. Lung tumor development was preceded by aberrant expansion of bronchioalveolar stem/progenitor and alveolar type II cells, as well as increased expression of EGFR and its downstream signaling factors in the lung of Tip30−/− mice. Moreover, TIP30 knockdown in human lung adenocarcinoma cells resulted in prolonged EGFR activity in early endosomes, delayed EGFR degradation, increased EGFR nuclear localization, leading to up-regulated pAKT and pERK1/2 expression. Importantly, in human lung adenocarcinomas, low TIP30 expression correlates with prolonged patient overall and post-progression survival times. Together, these results suggest that TIP30 functions as a tumor suppressor to inhibit EGFR cytoplasmic and nuclear signaling and suppress adenocarcinogenesis in the lung and highlight the potential of therapeutic strategies aiming at inhibiting EGFR signaling for patients with low TIP30 expression lung adenocarcinoma.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.