by using the lacz gene as a sensitive quantitative marker , analyses of micrometastasis development in the lung indicate that the ras oncogene contributes to the metastatic phenotype in this ej ha-ras model system , although further genetic and/or phenotypic alterations appear to be necessary for long-term growth and development into overt metastases .
C1513276
micrometastasis
C0027627
metastases