Sensitivity to extrinsically supplied interferon and the endogenous expression of interferon in melanoma cell lines.

Interferons (IFNs) have been shown to Induce loss of growth potential in melanoma cell lines. However, human melanomas have shown limited responsiveness to clinical therapy with IFN. In a previous study on melanoma cell lines we found that greatest sensitivity to IFN was found in cell lines with the greatest number of copies of chromosome 9p, where the IFN gene family is located.

S-phase fraction related to prognosis in localised prostate cancer. No specific significance of chromosome 7 gain or deletion of 7q31.1.

A flow-cytometric (FCM) and fluorescence in situ hybridization (FISH) study was performed in 153 patients with clinically localised prostate cancer (PC) to evaluate retrospectively the prognostic significance of DNA ploidy, S-phase fraction (SPF) and chromosome 7 copy number. Deletions in 7q31.1 were analysed in a subset of 26 tumours.

Prevalence of Klinefelter's syndrome in male breast cancer patients.

Klinefelter's syndrome (KS, XXY) as a risk factor for developing breast cancer was evaluated in a retrospective study of 93 unselected male breast cancer patients from the Healthcare region of Western Sweden. Archival normal material from lymph nodes or skin and subcutaneous tissue was examined using the FISH (fluorescence in situ hybridisation)-technique. The best yield of intact nuclei was obtained from lymph node tissue.

A rapid and simplified technique for analysis of archival formalin-fixed, paraffin-embedded tissue by fluorescence in situ hybridization (FISH).

We here present a simplification of the entire procedure for preparing formalin-fixed, paraffin-embedded tissue to be used for FISH-analysis. The steps for deparaffinisation and disintegration of the tissue to produce intact cell nuclei in a monodispersed suspension are detailed as well as the hybridisation steps. The procedure results in a clear cell suspension with intact cell nuclei and without clumped debris particles.

Action of interferon alpha and beta on four human melanoma cell lines in vitro.

Four human melanoma cell lines with different copy numbers of chromosomes 9 and 21q, as studied by the G-band technique, fluorescent in situ hybridisation (FISH) and Polymerase chain reaction (PCR), were tested for their sensitivity to Interferon-alpha (IFN-alpha) and Interferon-beta (IFN-beta) in relation to dosage of interferon genes (#9) and interferon receptor genes (#21p). The two most sensitive cell lines were those containing the highest numbers of #9 per cell, while the number of #21q copies (receptor genes) seemed to have no influence on the interferon sensitivity.