βIII-Tubulin: A novel mediator of chemoresistance and metastases in pancreatic cancer

Pancreatic cancer is a leading cause of cancer-related deaths in Western societies. This poor prognosis is due to chemotherapeutic drug resistance and metastatic spread. Evidence suggests that microtubule proteins namely, beta-tubulins are dysregulated in tumor cells and are involved in regulating chemosensitivity. However, the role of beta-tubulins in pancreatic cancer are unknown. We measured the expression of different beta-tubulin isotypes in pancreatic adenocarcinoma tissue and pancreatic cancer cells. Next, we used RNAi to silence beta III-tubulin expression in pancreatic cancer cells, and measured cell growth in the absence and presence of chemotherapeutic drugs. Finally, we assessed the role of beta III-tubulin in regulating tumor growth and metastases using an orthotopic pancreatic cancer mouse model. We found that beta III-tubulin is highly expressed in pancreatic adenocarcinoma tissue and pancreatic cancer cells. Further, we demonstrated that silencing beta III-tubulin expression reduced pancreatic cancer cell growth and tumorigenic potential in the absence and presence of chemotherapeutic drugs. Finally, we demonstrated that suppression of beta III-tubulin reduced tumor growth and metastases in vivo. Our novel data demonstrate that beta III-tubulin is a key player in promoting pancreatic cancer growth and survival, and silencing its expression may be a potential therapeutic strategy to increase the long-term survival of pancreatic cancer patients.
National Health and Medical Research Council (NHMRC); Cancer Council New South Wales; Cure Cancer Australia Foundation Grant; Cancer Institute NSW Fellowship; NHMRC CDF Fellowship; NHMRC Senior Research Fellowship