Expresión de Heat Shock Protein-90 (HSP-90) como factor predictor de la respuesta a radioterapia en pacientes con tumores de cabeza y cuello

Abstract

Introduction and objectivesHSP-90 is an intracellular protein that protects the cell from environmental stress situations. The overexpression of HSP-90 isoforms could serve as a mechanism of resistance to radiotherapy for tumour cells. We studied this effect in a sample of head and neck tumours. MethodsWe included 87 patients diagnosed with oral cavity, oropharynx, larynx and hypopharynx tumours. We studied the expression of the HSP-90 isoforms by real-time PCR on pre-treatment biopsy samples. We analysed the relationship between HSP-90 expression levels and local relapse of the tumour with CRT decision trees. ResultsThe expression levels of the inducible citosolic isoform (HSP90AA) allowed the definition of 2 groups of patients with different rates of local relapse. The group with a low expression level showed a 2.9% local relapse rate, while the group with a high expression level showed a 38.2% rate.Survival curves showed differences in time to local relapse for both groups of patients. These differences did not reach statistical significance. ConclusionsRadiotherapy response was related to expression levels of HSP-90 in a sample of head and neck cancer patients. This result could prove useful in the selection of treatments for this group of patients.