Biomarkers as predictors of response to cancer treatment

Introduction: Breast cancer treatment has experienced several changes in the last decades due to the innovation of genetic biomarkers. Presently, more women are being treated with neoadjuvant (preoperative) therapy which... [ view full abstract ]

Introduction: Breast cancer treatment has experienced several changes in the last decades due to the innovation of genetic biomarkers. Presently, more women are being treated with neoadjuvant (preoperative) therapy which involves chemotherapy or endocrine agents before surgery, for earlier-stage operable breast carcinoma. Following this mode of pre-operative systemic treatment could improve the surgical option and make inoperable tumors operable. It can also increase the breast conservation rate. Another key benefit of neoadjuvant therapy is monitoring response to the treatment. The good response to neoadjuvant therapy with complete pathological response (pCR) is a surrogate marker for overall survival.
Objective: The aim of this research was to demonstrate the gene expression changes with response to treatment. This information can be helpful to check the sensitivity of drug after short period of therapy. Specifically, to built a model to interrogate the association between neoadjuvent chemotherapy response (pCR in this case) and gene expression modules, recapitulating important biological processes such as proliferation, immune, stroma and ”druggable”oncogenic pathways in different breast cancer subtypes.
Patients and Methods: We searched for publicly available gene expression studies evaluating anthracycline with or without taxane-based neoadjuvant chemotherapy and identified eight studies with 996 patients. We computed 17 gene modules and calculated odds ratios (ORs) for pathologic complete response (pCR) for one-unit increases in scaled modules with and without adjustment for clinicopathologic characteristics.. Results: We demonstrated different biological processes and pathways are associated with pCR in different BC subtypes.