Differential pp60c-src activity in well and poorly differentiated human colon carcinomas and cell lines.

T K Weber; G Steele; I C Summerhayes

doi:10.1172/JCI115956

Differential pp60c-src activity in well and poorly differentiated human colon carcinomas and cell lines.

T K Weber, G Steele, and I C Summerhayes

Published September 1, 1992 - More info

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Abstract

The results presented in this report demonstrate increased pp60c-src kinase activity associated with moderate to well differentiated colon tumors, corroborating previous observations by other groups. Extension of this analysis to include a small number of poorly differentiated colon carcinomas revealed src kinase activity comparable to that observed in normal colonic mucosa, considerably less than that observed in moderate/well differentiated lesions. Correlations of src kinase activity with differentiation was confirmed within a panel of colon cell lines where increased activity, associated with moderate/well differentiated lines, was accompanied by increased expression of pp60c-src protein. Use of an antiphosphotyrosine antibody in immunoprecipitation revealed the presence of novel phosphotyrosyl cellular substrates in human colon cell lines displaying elevated pp60c-src kinase activity. These observations suggest a role for the src protooncogene in colonic differentiation pathways.

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