Changes in the Sensitivity of MCF-7 and MCF-7/DX Breast Cancer Cells to Cytostatic in the Presence of Metformin.

Multidrug resistance is a serious problem in modern medicine and the reason for the failure of various therapies. A particularly important problem is the occurrence of multidrug resistance in cancer therapies which affects many cancer patients. Observations on the effect of metformin-a well-known hypoglycemic drug used in the treatment of type 2 diabetes-on cancer cells indicate the possibility of an interaction of this substance with drugs already used and, as a result, an increase in the sensitivity of cancer cells to cytostatics. The aim of this study was to evaluate the effect of metformin on the occurrence of multidrug resistance of breast cancer cells. The MCF-7-sensitive cell line and the MCF-7/DX cytostatic-resistant cell line were used for this study. WST-1 and LDH assays were used to evaluate the effects of metformin and doxorubicin on cell proliferation and viability. The effect of metformin on increasing the sensitivity of MCF-7 and MCF-7/DX cells to doxorubicin was evaluated in an MDR test. The participation of metformin in increasing the sensitivity of resistant cells to the effect of the cytostatic (doxorubicin) has been demonstrated.

[A multidirectional effect of metformin]. / Molekularne podstawy wielokierunkowego dzialania metforminy.

Diabetes as chronic civilization disease, very often occurs together with health disorders. One of the basic pharmaceuticals commonly used in her therapy is metformin. Many other positive effects, not related to diabetes, have been observed in tatients treated with metformin for a long time. These are: positive changes in diagnostiic parameters, protection against cancer development, less frequent occurrence of other pathologies and diseases, increased sensitivity to selected drugs (e.g. cytostatics), delayed aging processes of organism. In addition to the molecular changes resulting in a hypoglycemic effect, the most common modifications of gene expression have been described, indicated as the basis for the anti-aging, anti-atherosclerotic and anticancer effects of this drug and its effect on melanogenesis or the nervous system. The results presented in the study are very promising, but most of them relate to experiments carried out in cell cultures or animals. The possibility of obtaining similar effects in humans requires much more research.

[Anti-cancer properties of dichloroacetate]. / Przeciwnowotworowe wlasciwosci dichlorooctanu.

One of the hallmarks of cancer cells is aerobic glycolysis (the Warburg effect). The effect of dichloroacetate (DCA) is to switch glucose metabolism (cellular respiration) to a more efficient process involving oxygen, reduce the production of lactic acid, activate the respiratory chain, change the potential of the mitochondrial membrane, and release pro-apoptotic mediators (cytochrome c and AIF) into the cytosol. As a result, the control over the mutated cells is improved, their sensitivity to various drugs or radiotherapy and their sensitivity to apoptosis increase. In the study the review of data on the mechanism of action of DCA on neoplastic cells was performed to indicate the side effects associated with the possible introduction of this compound to cancer therapy.