These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Evidence for selection of homogeneously staining regions in a human melanoma cell line. Author: Trent JM, Thompson FH, Ludwig C. Journal: Cancer Res; 1984 Jan; 44(1):233-7. PubMed ID: 6197160. Abstract: Cytogenetic analysis of tumor cells from a human malignant melanoma was performed on both the primary tumor colony-forming cells and a cell line (HA-A) established subsequently from the clonogenic population. Chromosome-banding analysis demonstrated identical karyotypic alterations in both the tumor colony-forming cells and the HA-A cell line, documenting their origin from a common precursor. The most distinctive chromosome alterations shared between tumor colony-forming cells and the HA-A cell line were double-minute bodies (DMs) and a homogeneously staining region (HSR) on chromosome 7 at band p22. This represents the first observation of DMs or HSRs in cells from a human malignant melanoma. The frequency of HSR-bearing cells observed in the original tumor was less than 1%, while DM-containing cells were present in greater than 90% of all cells examined. In contrast, serial chromosome harvests at early passage of the HA-A cell line revealed positive selection for HSR-bearing cells with concomitant loss of DM-containing cells after increasing time in vitro. Following the ninth serial passage in vitro, HSRs were observed in 100% of cells with DMs no longer observed in the HA-A cell line. The finding of an HSR-bearing marker in the original tumor sample supports the view that HSRs are not an artifact of in vitro monolayer growth. However, our results demonstrate that the frequency of HSR-bearing cells within established cell lines may reflect in vitro selection and therefore not accurately reflect the frequency of this population in vivo.[Abstract] [Full Text] [Related] [New Search]