Paclitaxel (PTX) is a chemotherapeutic agent affecting microtubule polymerization. The efficacy of PTX depends on the type of tumor, and its improvement would be beneficial in patients' treatment. Therefore, we tested the effect of slow sulfide donor GYY4137 on paclitaxel sensitivity in two different breast cancer cell lines, MDA-MB-231, derived from a triple negative cell line, and JIMT1, which overexpresses HER2 and is resistant to trastuzumab. In JIMT1 and MDA-MB-231 cells, we compared IC50 and some metabolic (apoptosis induction, lactate/pyruvate conversion, production of reactive oxygen species, etc.), morphologic (changes in cytoskeleton), and functional (migration, angiogenesis) parameters for PTX and PTX/GYY4137, aiming to determine the mechanism of the sensitization of PTX. We observed improved sensitivity to paclitaxel in the presence of GYY4137 in both cell lines, but also some differences in apoptosis induction and pyruvate/lactate conversion between these cells. In MDA-MB-231 cells, GYY4137 increased apoptosis without affecting the IP3R1 protein, changing the morphology of the cytoskeleton. A mechanism of PTX sensitization by GYY4137 in JIMT1 cells is distinct from MDA-MB-231, and remains to be further elucidated. We suggest different mechanisms of action for H2S on the paclitaxel treatment of MDA-MB-231 and JIMT1 breast cancer cell lines.

• Keywords
• apoptosis, breast cancer cell lines, metabolism, paclitaxel, slow sulfide donor,
• MeSH
• Apoptosis * drug effects   MeSH
• Drug Resistance, Neoplasm drug effects   MeSH
• Humans MeSH
• Morpholines * pharmacology   MeSH
• Cell Line, Tumor MeSH
• Breast Neoplasms * drug therapy   pathology   metabolism   MeSH
• Organothiophosphorus Compounds * pharmacology   MeSH
• Paclitaxel * pharmacology   MeSH
• Reactive Oxygen Species metabolism   MeSH
• Sulfides pharmacology   MeSH
• Check Tag
• Humans MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• GYY 4137 MeSH Browser
• Morpholines * MeSH
• Organothiophosphorus Compounds * MeSH
• Paclitaxel * MeSH
• Reactive Oxygen Species MeSH
• Sulfides MeSH

The sodium/calcium exchanger (NCX) is a unique calcium transport system, generally transporting calcium ions out of the cell in exchange for sodium ions. Nevertheless, under special conditions this transporter can also work in a reverse mode, in which direction of the ion transport is inverted-calcium ions are transported inside the cell and sodium ions are transported out of the cell. To date, three isoforms of the NCX have been identified and characterized in humans. Majority of information about the NCX function comes from isoform 1 (NCX1). Although knowledge about NCX function has evolved rapidly in recent years, little is known about these transport systems in cancer cells. This review aims to summarize current knowledge about NCX functions in individual types of cancer cells.

• Keywords
• apoptosis, calcium, cancer cells, sodium-calcium exchanger,
• MeSH
• Neoplasm Invasiveness MeSH
• Ion Transport MeSH
• Humans MeSH
• Neoplasms metabolism   MeSH
• Sodium-Calcium Exchanger metabolism   MeSH
• Sodium metabolism   MeSH
• Calcium metabolism   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Review MeSH
• Names of Substances
• Sodium-Calcium Exchanger MeSH
• Sodium MeSH
• Calcium MeSH