Abstract A30: Characterizing the non-linear dependency of the CDK5-Rb axis in non-small cell lung cancer

In spite of recent therapeutics advances and early detection, lung cancer is still the leading cause of cancer-associated deaths worldwide. The five-year survival rates for its two major subtypes, small-cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC) are estimated to be 6% and 18%, respectively. This high mortality is due to its aggressive nature even when detected at an early stage. Besides its aggressive nature and tendency for early metastasis, another feature of lung cancer is the inactivation of the retinoblastoma protein (Rb) that is observed in both lung cancer subtypes. NSCLC exhibits Rb inactivation by hyper-phosphorylation. Rb is phosphorylated by cyclin dependent kinases (CDKs) and their cyclin regulatory partners. CDK5 is a unique CDK because its regulatory partners, p35 and p39, are not cyclins, hence its function is not cell cycle related. This work aims to employ empirical modeling and statistical experimental design techniques to gain a comprehensive mechanistic understanding of metastasis. Previous mass spectroscopy experiments performed in our laboratory on a panel of NSCLC cell lines identified five-residues (S249, S612, S807, S811, and T821) whose phosphorylation is associated with lack of E-cadherin expression, and therefore may be associated with metastasis. Our hypothesis is that Rb inactivation via phosphorylation due to CDK5 leads to the acquisition of the epithelial-to-mesenchymal transition (EMT) phenotype and the disruption of cell-c...
Source: Cancer Research - Category: Cancer & Oncology Authors: Tags: Systems Biology Source Type: research