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Published on: May 17, 2013

Altered growth of human colon cancer cell lines disrupted at activated Ki-ras

S Shirasawa1, M Furuse, N Yokoyama

  • 1Department of Genetics, Kyushu University, Fukuoka, Japan.

Science (New York, N.Y.)
|April 2, 1993
PubMed

Insights

Activating mutations in the Ki-ras gene drive colorectal cancer by altering cell growth and differentiation. Disrupting these mutations in cancer cells reduced tumor growth and c-myc expression.

Area of Science:

  • Oncology
  • Molecular Biology
  • Genetics

Background:

  • Point mutations activating the Ki-ras proto-oncogene are found in approximately 50% of human colorectal tumors.
  • The specific role of activated Ki-ras in colorectal tumorigenesis requires further functional investigation.

Purpose of the Study:

  • To investigate the functional significance of activating Ki-ras mutations in colorectal cancer.
  • To elucidate the impact of activated Ki-ras on cell differentiation and growth.

Main Methods:

  • Utilized homologous recombination to disrupt activated Ki-ras genes in DLD-1 and HCT 116 colon carcinoma cell lines.
  • Compared the characteristics of gene-disrupted cells with their parental counterparts, including morphology, growth, and gene expression.

Main Results:

  • Cells with disrupted activated Ki-ras genes exhibited morphological alterations.
  • Loss of anchorage-independent growth and slower proliferation rates were observed in vitro and in vivo (nude mice).
  • Reduced expression of the c-myc oncogene was noted in cells lacking activated Ki-ras.

Conclusions:

  • The activated Ki-ras gene plays a critical role in colorectal tumorigenesis.
  • Activated Ki-ras influences colorectal cancer development by modulating cell differentiation and growth pathways.

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