Manoalide Shows Mutual Interaction between Cellular and Mitochondrial Reactive Species with Apoptosis in Oral Cancer Cells

Methanol Extract of Commelina Plant Inhibits Oral Cancer Cell Proliferation

Data regarding the effects of crude extract of Commelina plants in oral cancer treatment are scarce. This present study aimed to assess the proliferation-modulating effects of the Commelina sp. (MECO) methanol extract on oral cancer cells in culture, Ca9-22, and CAL 27. MECO suppressed viability to a greater extent in oral cancer cells than in normal cells. MECO also induced more annexin V, apoptosis, and caspase signaling for caspases 3/8/9 in oral cancer cells. The preferential antiproliferation and apoptosis were associated with cellular and mitochondrial oxidative stress in oral cancer cells. Moreover, MECO also preferentially induced DNA damage in oral cancer cells by elevating γH2AX and 8-hydroxyl-2′-deoxyguanosine. The oxidative stress scavengers N-acetylcysteine or MitoTEMPO reverted these preferential antiproliferation mechanisms. It can be concluded that MECO is a natural product with preferential antiproliferation effects and exhibits an oxidative stress-associated mechanism in oral cancer cells.

Synergistic Antiproliferation of Cisplatin and Nitrated [6,6,6]Tricycle Derivative (SK2) for a Combined Treatment of Oral Cancer Cells

SK2, a nitrated [6,6,6]tricycle derivative with an n-butyloxy group, showed selective antiproliferation effects on oral cancer but not on normal oral cells. This investigation assessed for the first time the synergistic antiproliferation potential of cisplatin/SK2 in oral cancer cells. Cell viability assay at 24 h showed that a low dose of combined cisplatin/SK2 (10 μM/10 μg/mL) provided more antiproliferation than cisplatin or SK2 alone. Cisplatin/SK2 triggered also more apoptosis inductions in terms of subG1 accumulation, annexin V, pancaspase, and caspase 3/8/9 measurements. Moreover, cisplatin/SK2 provided more oxidative stress and DNA damage in oral cancer cells than independent treatments. Oxidative stress inhibitors rescued the cisplatin/SK2-induced antiproliferation and oxidative stress generation. Moreover, cisplatin/SK2 induced more antiproliferation, apoptosis, oxidative stress, and DNA damage in oral cancer cells than in normal oral cells (S-G). In conclusion, low-dose cisplatin/SK2 combined treatment promoted selective and synergistic antiproliferation in oral cancer cells depending on oxidative-stress-associated responses.

Withaferin A Triggers Apoptosis and DNA Damage in Bladder Cancer J82 Cells through Oxidative Stress

Withaferin A (WFA), the Indian ginseng bioactive compound, exhibits an antiproliferation effect on several kinds of cancer, but it was rarely reported in bladder cancer cells. This study aims to assess the anticancer effect and mechanism of WFA in bladder cancer cells. WFA shows antiproliferation to bladder cancer J82 cells based on the finding of the MTS assay. WFA disturbs cell cycle progression associated with subG1 accumulation in J82 cells. Furthermore, WFA triggers apoptosis as determined by flow cytometry assays using annexin V/7-aminoactinomycin D and pancaspase detection. Western blotting also supports WFA-induced apoptosis by increasing cleavage of caspases 3, 8, and 9 and poly ADP-ribose polymerase. Mechanistically, WFA triggers oxidative stress-association changes, such as the generation of reactive oxygen species and mitochondrial superoxide and diminishment of the mitochondrial membrane potential, in J82 cells. In response to oxidative stresses, mRNA for antioxidant signaling, such as nuclear factor erythroid 2-like 2 (NFE2L2), catalase (CAT), superoxide dismutase 1 (SOD1), thioredoxin (TXN), glutathione-disulfide reductase (GSR), quinone dehydrogenase 1 (NQO1), and heme oxygenase 1 (HMOX1), are overexpressed in J82 cells. In addition, WFA causes DNA strand breaks and oxidative DNA damages. Moreover, the ROS scavenger N-acetylcysteine reverts all tested WFA-modulating effects. In conclusion, WFA possesses anti-bladder cancer effects by inducing antiproliferation, apoptosis, and DNA damage in an oxidative stress-dependent manner.