15792 β3-Tubulin knockdown impairs microtubule dynamics, induces cell cycle arrest, and decreases the spontaneous release of microvesicles in human skin malignant melanoma cells (A375)

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.

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In Vitro Anticancer Effects of All-trans Retinoic Acid in Combination with Dacarbazine against CD117+ Melanoma Cells

Drug Research ◽

10.1055/a-1240-0072 ◽

2020 ◽

Vol 70 (12) ◽

pp. 563-569

Author(s):

Bahareh Mohammadi Jobani ◽

Elham Mohebi ◽

Nowruz Najafzadeh

Keyword(s):

Cell Cycle ◽

Retinoic Acid ◽

Malignant Melanoma ◽

Cell Cycle Arrest ◽

Combined Treatment ◽

Melanoma Cells ◽

Cycle Arrest ◽

Trans Retinoic Acid ◽

All Trans Retinoic Acid

Abstract Background Malignant melanoma is a common form of skin cancer that contains different cell types recognized by various cell surface markers. Dacarbazine-based combination chemotherapy is frequently used for the treatment of melanoma. Despite its potent anticancer properties, resistance to dacarbazine develops in malignant melanoma. Here, we aim to improve response to dacarbazine therapy by pretreatment with all-trans retinoic acid (ATRA) in CD117+ melanoma cells. Methods The CD117+ melanoma cells were sorted from A375 malignant melanoma cell line using magnetic-activated cell sorting (MACS). The cell viability was examined by cell proliferation assay (MTT). Apoptosis was determined by acridine orange/ ethidium bromide staining. Indeed, we performed flow cytometry to evaluate the cell cycle arrest. Results Here, the CD117+ melanoma cells were incubated with various concentrations of ATRA, dacarbazine, and their combination to determine IC50 values. We found that 20 µM ATRA treatment followed by dacarbazine was found to be more effective than dacarbazine alone. There was an indication that the combination of ATRA with dacarbazine (ATRA/dacarbazine) caused more apoptosis and necrosis in the melanoma cells (P<0.05). Furthermore, ATRA/dacarbazine treatment inhibited the cell at the G0/G1 phase, while dacarbazine alone inhibited the cells at S phase. Conclusion Collectively, combined treatment with ATRA and dacarbazine induced more apoptosis and enhanced the cell cycle arrest of CD117+ melanoma cells. These results suggested that ATRA increased the sensitivity of melanoma cells to the effect of dacarbazine.

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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.

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