Bufotalin induces cell cycle arrest and cell apoptosis in human malignant melanoma A375 cells

Malignant melanoma is the most lethal type of skin cancer. Previous studies have shown that ailanthone has potent antitumor activity in a variety of cell lines. However, the anti-tumor effect of ailanthone on malignant melanoma remains unclear. To investigate the anti-tumor mechanisms of ailanthone in human melanoma B16 and mouse melanoma A375 cells, the cell counting kit-8 assay, colony formation assay, DNA content analysis, Hoechst 33258, and Annexin V-FITC/PI staining were used to assess cell proliferation, cell cycle distribution, and cell apoptosis, respectively. Western blotting was performed to evaluate the expression of cell cycle- and apoptosis-related proteins and regulatory molecules. The results showed that ailanthone significantly inhibited melanoma B16 and A375 cell proliferation as well as remarkably induced cell cycle arrest at the G0–G1 phase in B16 cells and the G2–M phase in A375 cells in a dose-dependent manner. Further investigation revealed that ailanthone promoted the expression of p21 and suppressed the expression of cyclin E in B16 cells or cyclin B in A375 cells through the PI3K-Akt signaling pathway. In addition, ailanthone induced B16 and A375 cell apoptosis via a caspase-dependent mechanism. Further studies showed that ailanthone remarkably downregulated Bcl-2 and upregulated Apaf-1 and Bax, and subsequently increased mitochondrial membrane permeabilization and released cytochrome c from the mitochondria in B16 cells and A375 cells. Taken together, ailanthone induces cell cycle arrest via the PI3K-Akt signaling pathway as well as cell apoptosis via the mitochondria-mediated apoptotic signaling pathway. Ailanthone may be potentially utilized as an anti-tumor agent in the management of malignant melanoma.

Download Full-text

ROS-Mediated Apoptosis and Genotoxicity Induced by Palladium Nanoparticles in Human Skin Malignant Melanoma Cells

Oxidative Medicine and Cellular Longevity ◽

10.1155/2017/8439098 ◽

2017 ◽

Vol 2017 ◽

pp. 1-10 ◽

Cited By ~ 29

Author(s):

Saud Alarifi ◽

Daoud Ali ◽

Saad Alkahtani ◽

Rafa S. Almeer

Keyword(s):

Cell Cycle ◽

Dna Damage ◽

Malignant Melanoma ◽

Cell Cycle Arrest ◽

Human Skin ◽

Palladium Nanoparticles ◽

Molecular Mechanisms ◽

Time Dependent ◽

Cycle Arrest ◽

A375 Cells

The present work was designed to investigate the effect of palladium nanoparticles (PdNPs) on human skin malignant melanoma (A375) cells, for example, induction of apoptosis, cytotoxicity, and DNA damage. Diseases resulting from dermal exposure may have a significant impact on human health. There is a little study that has been reported on the toxic potential of PdNPs on A375. Cytotoxic potential of PdNPs (0, 5, 10, 20, and 40 μg/ml) was measured by tetrazolium bromide (MTT assay) and NRU assay in A375 cells. PdNPs elicited concentration and time-dependent cytotoxicity, and longer exposure period induced more cytotoxicity as measured by MTT and NRU assay. The molecular mechanisms of cytotoxicity through cell cycle arrest and apoptosis were investigated by AO (acridine orange)/EtBr (ethidium bromide) stain and flow cytometry. PdNPs not only inhibit proliferation of A375 cells in a dose- and time-dependent model but also induce apoptosis and cell cycle arrest at G2/M phase (before 12 h) and S phase (after 24 h). The induction of oxidative stress in A375 cells treated with above concentration PdNPs for 24 and 48 h increased ROS level; on the other hand, glutathione level was declined. Apoptosis and DNA damage was significantly increased after treatment of PdNPs. Considering all results, PdNPs showed cytotoxicity and genotoxic effect in A375 cells.

Download Full-text

Anti-oncogenic MicroRNA-203 Induces Senescence by Targeting E2F3 Protein in Human Melanoma Cells

Journal of Biological Chemistry ◽

10.1074/jbc.m111.325027 ◽

2012 ◽

Vol 287 (15) ◽

pp. 11769-11777 ◽

Cited By ~ 79

Author(s):

Shunsuke Noguchi ◽

Takashi Mori ◽

Yusami Otsuka ◽

Nami Yamada ◽

Yuki Yasui ◽

...

Keyword(s):

Cell Cycle ◽

Cell Growth ◽

Malignant Melanoma ◽

Cell Cycle Arrest ◽

Ectopic Expression ◽

Melanoma Cells ◽

Microrna Target ◽

Human Malignant Melanoma ◽

Cycle Arrest ◽

Tissue Specimens

MicroRNAs regulate gene expression by repressing translation or directing sequence-specific degradation of their complementary mRNA. We recently reported that miR-203 is down-regulated, and its exogenous expression inhibits cell growth in canine oral malignant melanoma tissue specimens as well as in canine and human malignant melanoma cells. A microRNA target database predicted E2F3 and ZBP-89 as putative targets of microRNA-203 (miR-203). The expression levels of E2F3a, E2F3b, and ZBP-89 were markedly up-regulated in human malignant melanoma Mewo cells compared with those in human epidermal melanocytes. miR-203 significantly suppressed the luciferase activity of reporter plasmids containing the 3′-UTR sequence of either E2F3 or ZBP-89 complementary to miR-203. The ectopic expression of miR-203 in melanoma cells reduced the levels of E2F3a, E2F3b, and ZBP-89 protein expression. At the same time, miR-203 induced cell cycle arrest and senescence phenotypes, such as elevated expression of hypophosphorylated retinoblastoma and other markers for senescence. Silencing of E2F3, but not of ZBP-89, inhibited cell growth and induced cell cycle arrest and senescence. These results demonstrate a novel role for miR-203 as a tumor suppressor acting by inducing senescence in melanoma cells.

Download Full-text