No abstract

Melanoma is the most malignant skin cancer. Curcumin has shown to have therapeutic effects when used in the treatment of malignant diseases. However, the precise molecular mechanisms of its action are not fully elucidated. In this research, we hypothesized that reactive oxygen species (ROS) play a key role in curcumin induced DNA damage, apoptosis and cell dead. To test our hypothesis, cytotoxic, genotoxic, apoptotic, ROS generating and mitochondrial membrane potential (MMP) of curcumin on mouse melanoma cancer cells (B16-F10) and fibroblastic normal cells (L-929) were investigated. Our results demonstrated that curcumin decreased cell viability and MMP and, increased DNA damage, apoptosis and ROS levels in both melanoma cancer and normal cells in a dose dependent manner and, these activities were significantly higher in melanoma cells than in normal cells with higher concentrations. There were positive strong relationships between DNA damage, apoptosis, cytotoxicity and ROS generation and MMP levels in curcumin treated melanoma and normal cells.  In summary, this in vitro study provide clear evidence that curcumin induced DNA damage, apoptosis  and cytotoxicity via its pro-oxidant activity in a dose dependent manner in both cancer and normal cells and these activities were higher in cancer cells than those of normal cells.

Selective inhibition with sulphonamides of carbonic anhydrase (CA) IX reduces cell proliferation and induces apoptosis in human cancer cells. The effect on CA IX expression of seven previously synthesised sulphonamide inhibitors, with high affinity for CA IX, as well as their effect on the proliferation/apoptosis of cancer/normal cell lines was investigated. Two normal and three human cancer cell lines were used. Treatment resulted in dose- and time-dependent inhibition of the growth of various cancer cell lines. One compound showed remarkably high toxicity towards CA IX-positive HeLa cells. The mechanisms of apoptosis induction were determined with Annexin-V and AO/EB staining, cleaved caspases (caspase-3, caspase-8, caspase-9) and cleaved PARP activation, reactive oxygen species production (ROS), mitochondrial membrane potential (MMP), intracellular pH (pHi), extracellular pH (pHe), lactate level and cell cycle analysis. The autophagy induction mechanisms were also investigated. The modulation of apoptotic and autophagic genes (Bax, Bcl-2, caspase-3, caspase-8, caspase-9, caspase-12, Beclin and LC3) was measured using real time PCR. The positive staining using γ-H2AX and AO/EB dye, showed increased cleaved caspase-3, caspase-8, caspase-9, increased ROS production, MMP and enhanced mRNA expression of apoptotic genes, suggesting that anticancer effects are also exerted through its apoptosis-inducing properties. Our results show that such sulphonamides might have the potential as new leads for detailed investigations against CA IX-positive cervical cancers.

Carbonic anhydrase IX (CA IX) has recently been validated as an antitumor/antimetastatic drug target. In this study, we examined the underlying molecular mechanisms and the anticancer activity of sulfonamide CA IX inhibitors against cervical cancer cell lines. The effects of several sulfonamides on HeLa, MDA-MB-231, HT-29 cancer cell lines, and normal cell lines (HEK-293, PNT-1A) viability were determined. The compounds showed high cytotoxic and apoptotic activities, mainly against HeLa cells overexpressing CA IX. We were also examined for intracellular reactive oxygen species (ROS) production; intra-/extracellular pH changes, for inhibition of cell proliferation, cellular mitochondrial membrane potential change and for the detection of caspase 3, 8, 9, and CA IX protein levels. Of the investigated sulfonamides, one compound was found to possess high cytotoxic and anti-proliferative effects in HeLa cells. The cytotoxic effect occurred via apoptosis, being accompanied by a return of pHe/pHi towards normal values as for other CA IX inhibitors investigated earlier.

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in a vast number of infections and deaths that deeply affect the world. When the virus encounters the host cell, it binds to angiotensin-converting enzyme 2, then the S protein of the virus is broken down by the transmembrane protease serine 2 with the help of furin, allowing the virus to enter the cell. The elevated inflammatory cytokines suggest that a cytokine storm, also known as cytokine release syndrome, may play a major role in the pathology of COVID-19. Therefore, the aim of this study is to investigate the relationship between circulating furin levels, disease severity, and inflammation in patients with SARS-CoV-2. A total of 52 SARS-CoV-2 patients and 36 healthy control participants were included in this study. SARS- CoV-2 patients were scored by the disease activity score. Serum furin, presepsin, and interleukin-6 (IL-6) levels were assessed using an enzyme-linked immunosorbent assay. The mean furin, presepsin, and IL-6 levels were significantly higher in the peripheral blood of SARS-CoV-2 compared to the controls ( p < 0.001). There were close positive relationship between serum furin and IL-6, furin and presepsin, and furin and disease severity ( r = 0.793, p < 0001; r = 0.521, p < 0.001; and r = 0,533, p < 0.001, respectively) in patients with SARS-CoV-2. These results suggest that furin may contribute to the exacerbation of SARS-CoV-2 infection and increased inflammation, and could be used as a predictor of disease severity in COVID-19 patients.