Determination of heterozygosis loss in different chromosomic loci in carcinomas of the lung, colon and breast: implications as prognostic factor

• Grant number: 91/03581-3
• Support Opportunities: Research Projects - Thematic Grants
• Start date: May 01, 1992
• End date: April 30, 1994
• Field of knowledge: Health Sciences - Medicine
• Principal Investigator: Ricardo Renzo Brentani
• Grantee: Ricardo Renzo Brentani
• Host Institution: Instituto Ludwig de Pesquisa sobre o Câncer (ILPC). São Paulo , SP, Brazil

Abstract

Chromosomic segments frequently lost in tumors can be considered as being candidate regions for the location of cancer suppressor genes. In this work, with the initial objective of determining the frequency of the loss of heterozygosis in solid tumors, we will analyze DNA samples of the tumor and the normal tissue of patients with carcinomas of the colon, lung and breast for RFLP analysis using 25 probes of polymorphic DNA distributed in 7 chromosomes. In order to attempt to evaluate the sequence in which the loss of heterozygosis occurs in cancer of the breast, we will use samples of tumors fixed and preserved in blocks of paraffin of patients with a minimum of five years "follow up”. The DNA samples extracted from normal tissue and from the tissue resulting from the dissection of specific stages for each tumor will be enlarged by the PCR method for a panel of highly polymorphic loci within regions which present frequent losses of heterozygosis (determined by the RFLP). (AU)