Cervical cancer cells induce apoptosis in TCD4+ lymphocytes through the secretion of TGF-ß.

PURPOSE: Tumor cells are known to secrete cytokines that modify their microenvironment in order to favor their survival and continuous proliferation. In this work, we evaluated if TGF-ß secreted in vitro by cervical cancer cells could interfere with the proliferation and survival of lymphocytes. METHODS: Lymphocytes were obtained from peripheral blood of healthy human volunteers, and isolated by density gradient centrifugation and cultured in 96-well plates. Lymphocyte proliferation was induced with phytohemaglutinin and co-cultured with conditioned media (CM) from cervical cancer cell lines, and the inhibition of proliferation was evaluated after 72 h by the incorporated radioactivity and a CFSE-labeling assay. TGF-ß quantification on these CM was evaluated by ELISA. Non-apoptotic cellular death was evaluated through disruption of cell membrane integrity by measuring the liberation of lactate dehydrogenase. The apoptosis process was evaluated by annexin-V and active caspase-3. The presence of CD4+ or CD8+ lymphocytes was evaluated by flow cytometry using specific antibodies. RESULTS: It was found that the conditioned media from these cells significantly inhibited the proliferation of lymphocytes and induced them to go into apoptosis. Antibodies against TGF-ß almost completely blocked this activity, suggesting that this cytokine is responsible for the inhibitory activity. When the induced apoptosis on subpopulations of lymphocytes was evaluated, it was detected that the CD4+ cells were specifically targeted. CONCLUSIONS: Cervical cancer cells secrete TGF-ß that inhibits lymphocyte proliferation and induces apoptosis in CD4+, but not in CD8+ lymphocytes.

Synthesis of 26-hydroxy-22-oxocholestanic frameworks from diosgenin and hecogenin and their in vitro antiproliferative and apoptotic activity on human cervical cancer CaSki cells.

Certain steroidal compounds have demonstrated an antiproliferative effect against several tumor cell lines; however, their complete role on cancer cells is not currently established. Herein, we report the synthesis and evaluation of two new 26-hydroxy-22-oxocholestanic steroids on cervical cancer CaSki cells. The title compounds were prepared from diosgenin and hecogenin in excellent yields. We determined their effect on cell proliferation, cell cycle, and cell death. The cytotoxic effect of the title compounds on CaSki and human lymphocytes was also evaluated, indicating that the main cell death process is not necrosis; the null effect on lymphocytes implies that they are not cytotoxic. The observation of apoptotic bodies as well as the increase in the expression of active caspase-3 along with the fragmentation of DNA confirmed that such new cholestanic frameworks induced apoptosis in tumor cells. Significantly, their antiproliferative activity on tumor cells did not affect the proliferative potential of normal fibroblasts from cervix and peripheral blood lymphocytes. The title compounds show selective antitumor activity and therefore serve as promising lead candidates for further optimization.

Evaluation of the antitumour activity of Rinvanil and Phenylacetylrinvanil on the cervical cancer tumour cell lines HeLa, CaSKi and ViBo.

Capsaicin is a potent inducer of apoptosis in tumourreceptor potential vanilloid 1 (TRPV1). The present study determined the IC50 and cytotoxic and apoptotic activities of the Capsaicin analogues Rinvanil and Phenylacetylrinvanil (PhAR) on three cervical cancer cell lines: HeLa, CaSKi and ViBo. These analogues possess an increased affinity for TRPV1 receptors. The IC50 obtained proved to be cytotoxic for all three cell lines; however, in the cells treated with Capsaicin both active caspase-3 and nuclear fragmentation were present. Capsaicin and its analogues also inhibited the normal proliferation of lymphocytes, suggesting that they are non-selective antitumour compounds. Finally, we discuss the possible loss of the relation between apoptosis and affinity to TRPV1, and the need for other strategies to synthesise Capsaicin analogues that can be useful in cancer treatments.

Synthesis and selective anticancer activity of steroidal glycoconjugates.

The synthesis of glucosamine derivatives of the steroidal sapogenins diosgenin and hecogenin using the N-phthaloyl protected trichloroacetimidate of d-glucosamine as donor and TMSOTf as promoter is reported. The corresponding glycoconjugates were transformed into their acetamido derivatives and the hydrochloride salt (from diosgenin) and tested against HeLa, CaSki, and ViBo cervicouterine cancer cells. These compounds showed low cytotoxicity values on tumor cells and human lymphocytes, indicating that the main cell death process is presumably not necrosis. Significantly, the antiproliferative activity of these compounds on tumor cells did not affect the proliferative potential of peripheral blood lymphocytes.

Synthesis and biological evaluation of the glycoside (25R)-3ß,16ß-diacetoxy-22-oxocholest-5-en-26-yl ß-d-glucopyranoside: a selective anticancer agent in cervicouterine cell lines.

The synthesis and biological evaluation of the new cholestane glycoside (25R)-3ß,16ß-diacetoxy-22-oxocholest-5-en-26-yl ß-d-glucopyranoside starting from diosgenin is described. This compound showed selective antiproliferative activity against CaSki, ViBo, and HeLa cervicouterine cancer cells. Its effect on the cell-cycle was determined. The cytotoxic effects of the title compound on cervicouterine cancer cell lines and human lymphocytes indicate that the main cell death process is not necrosis; hence it is not cytotoxic. The title compound induced apoptosis in cervicouterine cancer cells. Importantly, the antiproliferative activity on tumor cells did not affect the proliferative potential of peripheral blood lymphocytes. The title compound showed selective antitumor activity and greater antiproliferative activity than its aglycon, and therefore serves as a promising lead candidate for further optimization.

Synthesis of the steroidal glycoside (25R)-3ß,16ß-diacetoxy-12,22-dioxo-5α-cholestan-26-yl ß-D-glucopyranoside and its anti-cancer properties on cervicouterine HeLa, CaSki, and ViBo cells.

The synthesis of the new glycoside (25R)-3ß,16ß-diacetoxy-12,22-dioxo-5α-cholestan-26-yl ß-D-glucopyranoside starting from hecogenin is described. This compound showed anti-cancer activity against cervicouterine cancer cells HeLa, CaSki and ViBo in the micromolar range. Its effect on cell proliferation, cell cycle and cell death is also described. The cytotoxic effect of the title compound on HeLa, CaSki and ViBo cells and human lymphocytes was evaluated through the LDH released in the culture supernatant, indicating that the main cell death process is not necrosis; the null effect on lymphocytes implies that it is not cytotoxic. The ability of this novel glycoside to induce apoptosis was investigated; several apoptosis events like chromatin condensation, formation of apoptotic bodies, as well as the increase in the expression of active caspase-3 and the fragmentation of DNA confirmed that the compound induced apoptosis in cervicouterine cancer cells. Significantly, the antiproliferative activity on tumor cells did not affect the proliferative potential of normal fibroblasts from cervix and peripheral blood lymphocytes. The glycoside showed selective antitumor activity and greater antiproliferative activity than its aglycon; it therefore serves as a promising lead candidate for further optimization.