Effects of infiltrating lymphocytes and estrogen receptor on gene expression and prognosis in breast cancer.

The involvement of the immune system for the course of breast cancer, as evidenced by varying degrees of lymphocyte infiltration (LI) into the tumor is still poorly understood. The aim of this study was to evaluate the prognostic value of LI in breast cancer samples using microarray-based screening for LI-associated genes. Starting from the observation that most published ER gene signatures are heavily influenced by the LI effect, we developed and applied a novel approach to dissect molecular signatures.

Tyrosine kinase inhibitor STI571 (Imatinib) cooperates with wild-type p53 on K562 cell line to enhance its proapoptotic effects.

In order to ascertain whether p53 has a role in chronic myeloid leukemia hematopoietic progenitor response to the innovative tyrosine kinase inhibitor STI571 (Imatinib), we overexpressed a wild type (wt) p53 construct in the K562 cell line, generated from a human blast crisis and lacking endogenous p53. Wt p53 overexpression was associated with a significant reduction of bcr-abl expression levels resulting, at least in part, from post-transcriptional events affecting the stability of p210 bcr-abl fusion protein. Moreover, we demonstrated that p53 overexpression enhances the commitment to the apoptotic death fate of K562 following its in vitro exposure to 1 microM STI571.