M6P/IGF2 receptor: a candidate breast tumor suppressor gene.

Journal Article

The mannose 6-phosphate/insulin-like growth factor 2 receptor (M6P/IGF2r) functions in the activation of TGFbeta, a potent growth inhibitor for most cell types, the degradation of the mitogen, IGF2, and the intracellular trafficking of lysosomal enzymes. We have found its expression to be significantly reduced in both rat and human hepatocellular carcinomas (HCCs) and recently reported loss of heterozygosity (LOH) at this locus with mutations in the remaining allele in human liver tumors. Using the polymerase chain reaction, we utilized two polymorphisms in the 3' untranslated region of M6P/IGF2r to screen breast tumors for LOH. Forty of 62 (65%) patients were informative (heterozygous) and 12/40 (30%) breast tumors had LOH; 5/19 (26%) carcinomas in situ (CIS) and 7/21 (33%) invasive carcinomas. To investigate the early molecular genetic events in breast carcinogenesis, we screened the CIS with LOH for mutations. In 2/5 (40%) of these tumors, missense mutations were found in the remaining allele that gave rise to significant amino acid substitutions. These findings provide evidence that M6P/IGF2r allelic loss is an early event in the etiology of breast cancer, that this gene functions as a tumor suppressor gene in the breast.

Full Text

Duke Authors

Cited Authors

  • Hankins, GR; De Souza, AT; Bentley, RC; Patel, MR; Marks, JR; Iglehart, JD; Jirtle, RL

Published Date

  • May 2, 1996

Published In

Volume / Issue

  • 12 / 9

Start / End Page

  • 2003 - 2009

PubMed ID

  • 8649861

International Standard Serial Number (ISSN)

  • 0950-9232

Language

  • eng

Conference Location

  • England