Association of Circulating Insulin-like Growth Factors and IGF Binding Protein with Early Cases of Cancer Cervix BC19-BC22
Dr. Praveen Sablania,
Associate Professor, Department of Biochemistry, Andaman and Nicobar Islands Institute of Medical Sciences,
DHS Annexe Building, Port Blair, Andaman and Nicobar Islands, India.
Introduction: Insulin-like Growth Factor (IGF) signaling pathway has important roles in regulating cellular proliferation, apoptosis, differentiation and transformation. IGF-axis is implicated in pathogenesis of several common cancers including cancer cervix and its pre cancer stage.
Aim: To measure the circulating levels of IGF-I, IGF-II and IGFBP-3 and evaluate their association with early stages of cancer cervix.
Materials and Methods: The present case-control study consisted of 29 histologically proven cases of early cancer cervix (FIGO Stage I and II) and 37 age matched cytologically proven normal healthy controls. The study was conducted in Department of Biochemistry, Maulana Azad Medical College, Delhi, India from May 2004-April 2007. Peripheral blood was drawn in a heparinized vial and plasma was separated by centrifugation and stored at -80°C till analysis. Concentration of IGF-I, IGF-II and IGFBP-3 was measured using commercially available ELISA kit (DRG Diagnostics) in units of ng/mL. Statistical analysis was done using SPSS statistics (V21.0) and Microsoft excel software, viz. Student-t-test for comparison of significant mean, binary logistic regression was used to measure Odds Ratios (OR). Bio-Effective Mitogen (BEM) was calculated as (IGF-I in nM+IGF-II in nM+100)–(90% IGFBP-3 in nM) and mitogenic index as BEM/10% IGFBP-3 in nM.
Results: Plasma levels of IGF-I were significantly decreased (p<0.01) while IGF-II levels were not significantly different between cases and controls (p=0.12). IGFBP-3 levels were decreased significantly in cases than controls (p<0.01). Mitogenic index was significantly increased in cases as compared to controls (p=0.01). OR for cancer cervix was calculated based on distribution of 50th percentile in control group and OR (95% CI) was 3.5 (1.04-11.73); p=0.04.
Conclusion: Circulating IGF-I, IGF-II and IGFBP-3 are in a dynamic relationship; hence, mitogenic index was educed from these factors. We found mitogenic index to be associated with cancer cervix in concordance to the cognizant role of IGFs and their binding proteins.