Dissemination in athymic XXXX of lacZ transfected @entity151 cells identified by X-gal staining.

@entity19 @entity151 @entity5 @entity3
The @entity151 cell lines GLC-2 and DMS 456 were genetically labeled with the lacZ gene and examined for invasive and metastatic potential in META/Bom @entity19 . The lacZ gene encodes the enzyme beta-D- galactosidase, and cells expressing this enzyme were identified by staining with the chromogenic substrate X-gal. lacZ expressing cells were investigated after subcutaneous (s.c.) inoculation and intravenous (i.v.) injection. The X-gal detection of beta-D-galactosidase activity proved to be a rapid and easy means for specific and highly sensitive identification of @entity3 . All primary s.c. @entity5 stained by X-gal. The @entity5 of GLC-2 regularly demonstrated local invasive growth and produced multiple @entity3 in several organs. In contrast, primary DMS 456 @entity5 only occasionally demonstrated local invasion and very rarely generated secondary foci. No experimental @entity3 were found after i.v. injection of the examined @entity5 lines. The results indicate an intratumoral heterogeneity among @entity5 in the capacity for invasion and metastatic spread. The different metastatic pattern of GLC-2 after s.c. and i.v. inoculation supports the hypothesis that initial steps of the metastatic cascade occurring in the @entity5 are necessary for the subsequent production of growing @entity3 .
