Effects of cyclosporin A on growth and polyamine metabolism of MOLT-4 T-lymphoblastic leukaemia cells

Coping with the cancer experience. I. Developing an education and support programme for cancer patients and their significant others

Cancer patients and their significant others need information to understand events throughout the course of cancer. They also need support in mobilizing coping strategies as situational demands exceed their personal resources. Following a learning-needs assessment, Swedish cancer patients and their significant others demonstrated a desire to learn not only about the disease and treatment procedures, but also about the adaptation process to live with the uncertainty inherent in a diagnosis of cancer. It has, however, repeatedly been reported that communication barriers exist, and that information does not always reach the intended target. Thus, to increase knowledge and facilitate efforts to cope with the cancer experience an approach was used in which the provision of information was combined with emotional support in an education course. Patients and their significant others (n = 149) were actively involved in developing the education and support programme together with extensive learning materials. The programme, entitled Learning to live with cancer, has its roots in the educational philosophy of human learning, and is based on the findings from the original learning-needs assessment.

Growth inhibition of human gastrointestinal cancer cells by cyclosporin A

We have studied the ability of cyclosporin A (CsA) to inhibit the growth of human AGS gastric and HT29 colon carcinoma cells in vitro. Using continuous drug exposure in growth assays of cultured tumour cells we found that CsA produced a dose-dependent growth inhibition in gastric and colon cancer cells with a half-maximal effect at 5 microM and 6 microM CsA respectively. The growth inhibition of CsA was reversible in AGS cells, when the tumour cells were incubated in normal growth medium following CsA treatment. Trypan blue dye exclusion in AGS cells indicated a cytostatic rather than a cytotoxic effect in the concentration range used. Coincubation of CsA-treated cells with 10-400 U/ml interleukin-2 (IL-2) could not abrogate this growth inhibition, suggesting an IL-2 independent mechanism of action. Flow-cytometric analysis did not reveal a phase arrest of the gastric cancer cells within the cell cycle. We conclude from our experiments that CsA cytostatically and reversibly inhibits the growth of human gastric cancer cells in a dose-dependent manner. In contrast to its mechanism of action in lymphocytes, this direct antiproliferative effect of CsA seems not to be mediated by an IL-2-dependent pathway or a cell-cycle-phase arrest of the tumour cells.

FK506 and cyclosporin a regulate proliferation and proto-oncogene expression in HTLV-1-associated myelopathy/tropical-spastic-paraparesis-derived T cells

Human T-cell-leukemia-virus-type-1 (HTLV-1) infection is associated with adult T-cell leukemia/lymphoma (ATL) and HTLV-1-associated myelopathy (HAM)/tropical spastic paraparesis (TSP). The T-cell-targeting immunosuppressants, FK506 and cyclosporin A (CsA), suppressed proliferation of the HAM/TSP-derived T-cell lines, H89-59, H89-79 and H109. FK506 and CsA also reduced expression of the proto-oncogenes, c-myc and c-fos, but not c-jun and interleukin-2-receptor-alpha (IL-2R alpha) gene in H109 cells. The growth-inhibitory effects of FK506 and CsA were not abrogated by interleukin 2 (IL-2). These results suggest that the inhibitory effects of FK506 and CsA are independent of IL-2, and are associated with the reduction of c-myc and c-fos gene expression.

Effects of cyclosporin A and a non-immunosuppressive analogue, O-acetyl cyclosporin A, upon the growth of parent and multidrug resistant human lung cancer cells in vitro

We have studied the ability of cyclosporin A (CsA) and a non-immunosuppressive analogue, O-acetyl cyclosporin A (OACsA, B3-243) to inhibit the growth of human lung cancer cells in vitro. Using continuous drug exposure and the MTT colorimetric assay to determine cell growth we found that CsA produced partial growth inhibition at doses ranging from 0.5 to 3.0 micrograms ml-1 (0.4-2.4 microM). At progressively higher doses, complete growth inhibition and in situ cell lysis were seen. The P-glycoprotein expressing multidrug resistant (MDR) variant H69/LX4 of the small cell line H69/P was less sensitive to cyclosporins than the parent line, but this was not true of the non-P-glycoprotein expressing MDR variants of large cell line COR-L23 or adenocarcinoma line MOR. Sensitivity to OACsA was approximately 2-fold higher than that to CsA in most of the lines although not in the most sensitive line, COR-L88. Even in COR-L88, exposed to CsA or OACsA for 24 h, clonogenic cell survival was reduced only to 50%. There was no reduction in polyamine content of COR-L23 or COR-L88 cells following 48 h of exposure to CsA or OACsA. The effects on cell growth could not be inhibited by the addition of exogenous putrescine, nor could they be enhanced by the addition of alpha-difluoromethylorthinine. It does not appear therefore that inhibition of polyamine synthesis is the basis of the observed growth inhibition.