A study of the production of the selected cytokines interleukin 1, interleukin 6, and tumour necrosis factor by certain tumours and tumour cell lines
An investigation was carried out to examine the production of the inflammatory cytokines IL1, IL1, IL6, TNF, and TNF in two tumour cell lines, the MCF-7 breast cell line and the T-24 bladder cell line, and in samples of breast, bladder, lung and ovarian tumours. Two methods were used to investigate cytokine production. These were the polymerase chain reaction method (PCR) to examine cytokine mRNA production and immuno-staining of frozen or paraffin-embedded tissue sections to demonstrate the presence of the cytokine polypeptide directly. In the PCR experiments, the most frequently found cytokine was IL6, followed by IL1. Only a few tumours of any type displayed TNF, and even fewer produced TNF. In the immunostaining experiments performed on frozen sections, IL1 and IL6 proteins were detected in sections of tumours which gave positive results with PCR. Cell phenotyping indicated that the IL1 and IL6 were probably being synthesised by the tumour cells themselves although there was lymphocyte infiltration in every section examined. In the immuno-histology study performed on the paraffin-embedded sections, a new collection of tumours was used. These tumours were not subjected to parallel PCR due to size of tumour samples being too small. The results obtained from these experiments conflicted with the results observed in the PCR study. IL1 was detected in all of the breast tumours used for immuno-histology but in none of the breast tumours in the PCR experiments. While the conflict could not definately be resolved, it was thought that the results of the immuno-histology experiments were more accurate as they detected expression of cytokine protein on a cellular scale. The immuno-histology experiments demonstrated that some tumour cells produced IL1 in breast and bladder carcinomas, and some produced IL6 in breast and lung carcinomas.