Home    Missions and Scope    Editorial Board     Instructions for Authors    Contact Us

The Implications of Higher TGF-β1, IGF-II and IGF-1R mRNA Expression in Infiltrating Breast Carcinoma and Their Association with Tumorigenesis and Angiogenesis

¹Department of Microbiology and Immunology, University of Miami, Miller School of Medicine, Miami, Florida-33136, USA.

²Department of Immunopathology, ³Histopathology and ⁴General Surgery, Postgraduate Institute of Medical Education & Research, Chandigarh, India

*Corresponding Author:

Sunil K. Arora, Ph.D., MNAMS

Additional Professor

Department of Immunopathology

Postgraduate Institute of Medical Education & Research,

Chandigarh-160012, India

Ph.: 0091-172-2755192, FAX: 0091-172-2744401

Email: skarora_in@yahoo.com

Abstract

Insulin-like growth factor (IGF) and transforming growth factor (TGF) systems are implicated in breast tumorigenesis and are known to facilitate angiogenesis. The aim of the present study was to analyze intratumoral expression of various growth factors i.e TGF-β1, IGF-II, IGF-1R and to determine, whether their expression correlated with angiogenesis and other clinicopathological factors in infiltrating breast carcinoma in North Indian patients. Intratumoral expression of TGF-β1, IGF-II and IGF-1R genes was analyzed by RT-PCR in 60 biopsies of infiltrating breast carcinoma and compared that with its levels in their adjacent normal tissue. A comparative analysis of expression of each factor was done along with their relationship with angiogenesis in terms of intratumoral expression of vascular endothelial growth factor (VEGF, an invasogenic and angiogenic growth factor) and intratumoral microvessel density (IMD, a prognostic marker for angiogenesis). The relative mRNA abundance of all these genes was found to be higher in tumor tissues as compared to normal tissues. Statistical analysis of data revealed significantly higher values of TGF-β1 transcripts in tumor tissues (p<0.001) as compared to normal tissues, that relate positively with the expression of angiogenic factors like VEGF and IMD in the tumor microenvironment. Further a significant correlation between expression of IGF-1R and higher grade tumors (p<0.05) was observed. A linear association of intratumoral TGF-β1 expression with invasion and vascularity suggests/indicates a role of TGF-β1 in the pathogenesis of tumor angiogenesis.

Keywords:  IGF-II; IGF-1R; TGF-β1; VEGF; intratumoral microvessel density (IMD); infiltrating breast carcinoma.

Download the full article (PDF)