Abstract A181: IGF-IR expression predicts responsiveness to ionizing radiation in patients with locally advanced cervical cancer.

Background: The aim of the present study was to evaluate a possible association of expression IGF-IR, IGF-I, IGF-II, GAPDH and hemoglobin levels with tumor response to radiotherapy alone in patients HPV 16 positive with locally advanced cervical cancer. Methods: In this study of case-control nested in a cohort, 38 patients were included to whom tumor sample in fresh of the transformation zone of cervix was taken them before treatment. All of them were treated with exclusive pelvic external beam radiotherapy plus intracavitary brachytherapy. Response was defined as no evidence of residual disease after clinical examination by measuring tumor size, three months after the completion of the therapeutic sequence. Gene expression levels before radiotherapy were compared between complete response and non response. Results: A major increase was observed in gene expression IGF-IR (34%), followed by the expression of IGF-II (24%) in the cases of cancer in comparison with either the control group or normal tissue samples of the transformation zone of cervix obtained from non-oncologic patients treated by hysterectomy. GAPDH expression was directly correlated with the IGF-IR & IGF-II co expression under hemoglobin lower than 11g/dl (p=0.05). Patients with IGF-IR expression had 26.8 times more risk of treatment failure (p=0.018). Conclusion: This is the first report in the clinical setting that relates the expression of IGF-IR as a strong marker of responsiveness. Therefore, the IGF-IR can be considered as a molecular target for optimizing the treatment of cervical cancer with radiotherapy. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr A181.