The application of antidepressant drugs in cancer treatment

Antidepressants refer to psychotropic drugs which are used to treat mental illness with prominent emotional depression symptoms. It was reported that antidepressants had associated with anti-carcinogenic function which was associated with various signaling pathways and changing of microenvironment. Its mechanism includes cell apoptosis, antiproliferative effects, mitochondria-mediated oxidative stress, DNA damaging, changing of immune response and inflammatory conditions, and acting by inhibiting multidrug resistance of cancer cells. Accumulated studies showed that antidepressants influenced the metabolic pathway of tumor cells. This review summarized recent developments with the impacts and mechanisms of 10 kinds of antidepressants in carcinostasis. Antidepressants are also used in combination therapy with typical anti-tumor drugs which shows a synergic effect in anti-tumor. By contrast, the promotion roles of antidepressants in increasing cancer recurrence risk, mortality, and morbidity are also included. Further clinical experiments and mechanism analyses needed to be achieved. A full understanding of the underlying mechanisms of antidepressants-mediated anticarcinogenic effects may provide new clues for cancer prevention and clinical treatment.

Action of the insecticide cyfluthrin on Ca2+ signal transduction and cytotoxicity in human osteosarcoma cells

Cyfluthrin is a pyrethroid insecticide and common household pesticide. The effect of cyfluthrin on Ca²⁺-related physiology in human osteosarcoma is unclear. This study investigated the effect of cyfluthrin on cytosolic-free Ca²⁺ concentrations ([Ca²⁺]_i) and viability in MG63 human osteosarcoma cells. Cyfluthrin concentration-dependently induced [Ca²⁺]_i rises. Cyfluthrin-induced Ca²⁺ entry was confirmed by the Mn²⁺-induced quench of fura-2 fluorescence. Cyfluthrin at concentrations of 10-100 μM induced [Ca²⁺]_i rises. Ca²⁺ removal reduced the signal by approximately 50%. Cyfluthrin (100 μM) induced Mn²⁺ influx suggesting Ca²⁺ entry. Cyfluthrin-induced Ca²⁺ entry was inhibited 50% by protein kinase C (PKC) activator (phorbol 12-myristate 13-acetate) and inhibitor (GF109203X) and also by three inhibitors of store-operated Ca²⁺ channels: nifedipine, econazole, and SKF96365. In Ca²⁺-free medium, treatment with the endoplasmic reticulum Ca²⁺ pump inhibitor thapsigargin (TG) completely inhibited cyfluthrin-evoked [Ca²⁺]_i rises. Conversely, treatment with cyfluthrin abolished TG-evoked [Ca²⁺]_i rises. Inhibition of phospholipase C (PLC) with 1-[6-[((17β)-3-methoxyestra-1,3,5[10]-trien-17-yl)amino]hexyl]-1H-pyrrole-2,5-dion abolished cyfluthrin-induced [Ca²⁺]_i rises. Cyfluthrin at 25-65 μM decreased cell viability, which was not reversed by pretreatment with the Ca²⁺ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester. Together, in MG63 cells, cyfluthrin induced [Ca²⁺]_i rises by evoking PLC-dependent Ca²⁺ release from the endoplasmic reticulum and Ca²⁺ entry via PKC-sensitive store-operated Ca²⁺ entry. Cyfluthrin also caused Ca²⁺-independent cell death.