Chemosensitizer effect of cisplatin-treated bladder cancer cells by phenazine-5,10-dioxides

Valeric acid acts as a novel HDAC3 inhibitor against prostate cancer

Prostate cancer is the second cause of cancer-related deaths in men worldwide, and new agents for curing the disease are still needed. In this study, we theoretically and experimentally demonstrated that valeric acid (VA) was a HDAC inhibitor, and anti-cancer efficacy of VA in prostate cancer cells was also observed using either 2D or 3D culture systems. VA was cytotoxic for prostate cancer cells but low toxic to normal cells. VA significantly inhibited E2F1/E2F3 expression but increased CASP3 activity. In vivo mouse models further showed its anti-cancer activity and potential property of chemosensitizer with promoting apoptosis. The findings suggest that VA acts as a HDAC3 inhibitor with anti-cancer effect on prostate cancer by regulating E2F1/E2F3/CASP3 axis.

Advances in Phenazines over the Past Decade: Review of Their Pharmacological Activities, Mechanisms of Action, Biosynthetic Pathways and Synthetic Strategies

Phenazines are a large group of nitrogen-containing heterocycles, providing diverse chemical structures and various biological activities. Natural phenazines are mainly isolated from marine and terrestrial microorganisms. So far, more than 100 different natural compounds and over 6000 synthetic derivatives have been found and investigated. Many phenazines show great pharmacological activity in various fields, such as antimicrobial, antiparasitic, neuroprotective, insecticidal, anti-inflammatory and anticancer activity. Researchers continued to investigate these compounds and hope to develop them as medicines. Cimmino et al. published a significant review about anticancer activity of phenazines, containing articles from 2000 to 2011. Here, we mainly summarize articles from 2012 to 2021. According to sources of compounds, phenazines were categorized into natural phenazines and synthetic phenazine derivatives in this review. Their pharmacological activities, mechanisms of action, biosynthetic pathways and synthetic strategies were summarized. These may provide guidance for the investigation on phenazines in the future.

MiR-486-5p enhances cisplatin sensitivity of human muscle-invasive bladder cancer cells by induction of apoptosis and down-regulation of metastatic genes

OBJECTIVES

Cisplatin is one of the common chemotherapy drugs for bladder cancer, and resistance to this drug is one of the major obstacles to effective chemotherapy. MicroRNAs (miRNAs) are a category of small noncoding RNAs that can regulate the expression of numerous genes. Recent studies showed that miRNAs can act as a powerful regulator of chemo-sensitivity in cancer cells. Hence, this study aimed to investigate the effects of miRNA-486-5p on cisplatin-sensitivity of different bladder cancer cells.

MATERIAL AND METHODS

The 5637 and EJ138 cancer cells were treated with miRNA-486-5p and cisplatin, individually or in combination.

RESULTS

Afterward, the cytotoxicity effects of these treatments were determined by MTT assay and the increased cisplatin-sensitivity observed in both cell lines, especially, 5637 cells. Moreover, subG1 phase cell cycle arrest, changes in the expression of caspase-9, caspase-3, P53, SIRT1, OLFM4, SMAD2, and Bcl-2 genes and nuclear fragmentation also revealed the induction of apoptosis in all treatments, which increased in combination groups. Also, the combination of miRNA-486-5p with cisplatin significantly down-regulated the expression of migration associated genes including ROCK, CD44, and MMP-9 as compared with cisplatin alone.

CONCLUSION

Altogether, these results indicated that the miRNA-486-5p could induce apoptosis and inhibit cell migration ability of the cells. It seems that pre-electroporation of cells with miRNA-486-5p has useful results in the enhancement of cisplatin sensitivity of 5637 and EJ138 cancer cells and this combination may be a promising treatment strategy for bladder cancer therapy.

Chemosensitizing Effect of Cernumidine Extracted from Solanum cernuum on Bladder Cancer Cells in Vitro

Cernumidine (CER) is a guanidinic alkaloid isolated from Solanum cernuum leaves. In this work, we investigated the cytotoxicity, chemosensitizing effect of cernumidine to cisplatin (cDDP) and the possible mechanism of action of the combination on bladder cancer cells. Cernumidine showed cytotoxicity and could sensitize bladder cancer cells to cisplatin. The combination of CER+cDDP inhibited cell migration on T24 cells. CER+cDDP down-regulated MMP-2/9 and p-ERK1/2, while it increased EGFR activity corroborating the observed cell migration inhibition. Down-regulation of Bcl-2 and up-regulation pro-apoptotic Bax and further depletion of the mitochondrial membrane potential (ΔΨm) indicates that mitochondria play a central role in the combination treatment inducing the mitochondrial signaling pathway of apoptosis in T24 cells. Our data showed that the alkaloid cernumidine is worthy of further studies as a chemosensitizing agent to be used in complementary chemotherapy.