Role of chromosomal instability and clonal heterogeneity in Breast Cancer: a pilot study.

Chromosomal instability (CI), defined as cell-to-cell variability in the number or structure of chromosomes, has been recognized as a hallmark of cancer and a source of genetic variation (clonal heterogeneity - HC) that favors tumor adaptation to stressful environments.

Breast Cancer (CS) is characterized by unstable karyotypes, and recent reports have indicated that HF can influence the response to different chemotherapy regimens in HER2 positive (HER2+) tumors.

However, information on the role of IC in other CS subtypes is rare or absent.

A greater understanding of the role of IC and HC in CS could help optimize existing therapeutic regimens.

Objectives: 1) To evaluate HF and HC in a group of 40 patients with estrogen receptor positive (ER+)/HER2-negative (HER2-) CS and 40 patients with ER negative (ER-)/HER2- CS with prolonged follow-up, and 2)

Establish associations between HF and HC with clinicopathological and sociodemographic parameters and response to treatment.

Methodology: Through the application of Molecular Cytogenetics (FISH) techniques, IC and HC will be evaluated in a population of patients with CS diagnosed at the Méderi University Hospital between 2000 and 2015, and correlations between IC and HC will be determined. with clinicopathological, sociodemographic characteristics and response to therapy.

Expected results: By carrying out this study we hope to find differences of clinical impact, at the level of IC and HC according to the state of the RE, as well as we hope to find associations between the level of IC and HC with the response to the therapy and with clinical-pathological and sociodemographic parameters.

Chromosomal instability, clonal heterogeneity, Breast Cancer.