ABSTRACT
Background/Aim: We aimed to investigate the in vitro modulating effects of medicarpin on the PI3K/AKT signal pathway gene expressions in head and neck squamous cell carcinoma (HNSCC). Materials and Methods: The effect of medicarpin on PTEN and other associated genes in the PTEN/AKT signal pathway was investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, real-time quantitative polymerase chain reaction, and Western blot analysis in the SCCL-MT1 (HNSCC) and control (HEK-293) cell lines. Results: The IC50 dose was 80 µM as a result of medicarpin treatment on HNSCC cells (P = 0.0006). It was found that PTEN and AKT gene expressions increased after the medicarpin administration while PDK1 gene expression was decreased in SCCL-MT1 cells (P = 0.0002, P = 0.0003, and P = 0.05, respectively). Protein expression results showed that medicarpin-treated cells significantly increased in pAKT (P = 0.024), pPTEN (P = 0.032), and decreased pPDK1 (P = 0.059) in SCCL-MT1. Conclusions: Our data show that medicarpin modulates HNSCC cells by increasing the PTEN and decreasing PDK1 expressions. PDK1 gene expression effects mTOR pathway which may increase AKT gene. Our study suggests that both medicarpin extracts combination with the HNSCC drug may be more effective in cancer treatment. Future prospective studies that integrate molecular and pharmacogenetic studies are crucial for revealing the mechanism and preventive medical efforts.
Subject(s)
Head and Neck Neoplasms , Proto-Oncogene Proteins c-akt , Cell Line, Tumor , Cell Proliferation , HEK293 Cells , Head and Neck Neoplasms/drug therapy , Head and Neck Neoplasms/genetics , Humans , PTEN Phosphohydrolase/genetics , PTEN Phosphohydrolase/metabolism , Phosphatidylinositol 3-Kinases/genetics , Phosphatidylinositol 3-Kinases/metabolism , Prospective Studies , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , Pterocarpans , Signal Transduction , Squamous Cell Carcinoma of Head and Neck/drug therapy , Squamous Cell Carcinoma of Head and Neck/geneticsABSTRACT
Melatonin is a hormone of the pineal gland that has a wide range of biological effects such as antioxidant, anti-inflammatory, and anti-tumor activity. Previous studies have shown that melatonin also affects survival, proliferation, and apoptosis of the cells. In this study, we investigated the effect of melatonin on apoptosis, self-renewal, and differentiation. For this purpose, MCF-7 and HEK293 cells were subjected to melatonin treatment. Expression of genes related to apoptosis (Bax and Bcl2) and self-renewal and differentiation (Oct4, Sox2, and Nanog) analyzed after the sorting of cancer stem cells from MCF-7 cells. Results showed that the effect of melatonin is dependent on the melatonin concentration and treatment periods. Melatonin treatment decreased the cell proliferation rate of MCF-7 in contrast to HEK293. Also, this treatment increased apoptosis in MCF-7 cells and decreased in HEK293 cells. Gene expression of Nanog was decreased and Sox2 was increased in both cell groups after the melatonin treatment. Expression of Oct4 was decreased in MCF-7 cells and increased in HEK293 cells. We determined that melatonin decreases apoptosis and differentiation of stem cells in normal HEK293 stem cells, but increases apoptosis and differentiation in the MCF-7 cancer stem cells.
Subject(s)
Apoptosis/drug effects , Cell Differentiation/drug effects , Melatonin/pharmacology , Neoplastic Stem Cells/drug effects , Blotting, Western , Flow Cytometry , HEK293 Cells , Humans , MCF-7 CellsABSTRACT
Tunicamycin is an inhibitor of glycosylation that disturbs protein folding machinery in eukaryotic cells. Tunicamycin causes accumulation of unfolded proteins in cell endoplasmic reticulum (ER) and induces ER stress. ER stress is an essential mechanism for cellular homeostasis has role in cell death via reprogramming of protein processing, regulation of autophagy and apoptosis. In this study we show effect of tunicamycin on subpopulation and invasion of CD44+/CD24- MCF7 breast cancer stem cells. CD44+/CD24- cells were isolated from MCF7 cell line by fluorescence activated cell sorting (FACS) and treated with tunicamycin. ER stress was monitored by evaluation of X-box binding protein 1(XBP-1) mRNA splicing, cleaved activating transcription factor 6 (ATF6) nuclear translocation and CCAAT/enhancer-binding protein homologous protein (CHOP) expression. CD44+/CD24- subpopulation was analyzed using flow cytometry. Invasion was investigated by scratch assay, trypan blue staining, 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide (MTT) proliferation and in vitro migration assays. Increased level of spliced XBP-1, ATF6 nuclear translocation and CHOP protein expression were detected in CD44+/CD24- and original MCF7 cells treated with tunicamycin. Also, a significant decline in CD44+/CD24- cell subpopulation was determined in the cells treated with tunicamycin. The results also showed inhibited invasion, increased cell death, suppressed proliferation and reduced migration in the CD44+/CD24- and CD44+/CD24- rich MCF7 cell culture, under effect of tunicamycin. Our results indicate that CD44+/CD24- phenotype MCF7 cells are susceptible to tunicamycin. The results showed that tunicamycin-induced ER stress suppresses CD44+/CD24- phenotype cell subpopulation and in vitro invasion and accelerates tumorosphore formation. These results suggest that tunicamycin-induced ER stress inhibits CD44+/CD24- phenotype MCF7 breast cancer stem cells. We conclude that using ER-targeting chemicals like tunicamycin is an interesting approach to target breast cancer stem cells inside tumor.
