Background and Objectives: Metoclopramide is an antagonist of dopamine D2 receptor and is capable of alleviating chemotherapy-induced nausea and vomiting. However, its underlying mechanisms and function in improving the efficiency of chemotherapy are not fully understood. In this study, we investigated the sensitizing effect of metoclopramide on the platinum-based drugs-mediated apoptosis in human head and neck cancer cells.Subjects and Method Apoptosis was analyzed using a cell-based cytometer. The protein expression and messenger ribonucleic acid (mRNA) levels were assessed by Western blotting and real-time polymerase chain reaction, respectively. Results: Metoclopramide sensitized the platinum-based drug (cisplatin and oxaliplatin)-mediated apoptosis in AMC-HN4 cells, but not in normal cells. Mechanistically, we found that metoclopramide decreased Mcl-1 protein expression through post-translational regulation. Moreover, the overexpression of Mcl-1 prevented apoptosis by combined treatment of metoclopramide and platinum-based drugs. Conclusion Metoclopramide induced proteasome-mediated Mcl-1 downregulation, resulting in increased sensitivity to platinum-based drugs.

BACKGROUND/OBJECTIVES: Rosa hybrida has been demonstrated to exert biological effects on several cell types. This study investigated the efficacy of the edible ethanol extract of R.hybrida (EERH) against human colorectal carcinoma cell line (HCT116) cells.MATERIALS/METHODS: HCT116 cells were cultured with different concentrations of EERH (0, 400, 600, 800, and 1,000 µg/mL) in Dulbecco’s modified Eagle medium. Cell viability was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide and viable cell counting assays. Cell cycle pattern was observed by flow cytometry analysis. The wound-healing migration assay, invasion assay, and zymography were used to determine the migratory and invasive level of HCT116 cells treated with EERH. The protein expression and binding ability level of HCT116 cells following EERH treatment were analyzed via immunoblotting and the electrophoretic mobility shift assay. RESULTS: EERH suppressed HCT116 cell proliferation, thus arresting the G1-phase cell cycle.It also reduced cyclin-dependent kinases and cyclins, which are associated with p27KIP1 expression. Additionally, EERH differentially regulated the phosphorylation of extracellular signal-regulated kinase 1/2, c-Jun NH2-terminal kinase, p38, and protein kinase B. Moreover, EERH treatment inhibited the enzymatic activity of matrix metalloproteinase-9 (MMP-9) and MMP-2, resulting in HCT116 cell migration and invasion. The EERH-induced inhibition of MMP-9 and MMP-2 was attributed to the reduced transcriptional binding of activator protein-1, specificity protein-1, and nuclear factor-κB motifs in HCT116 cells. Kaempferol was identified as the main compound contributing to EERH's antitumor activity. CONCLUSION EERH inhibits HCT116 cell proliferation and metastatic potential. Therefore, it is potentially useful as a preventive and curative nutraceutical agent against colorectal cancer.

Background and Objectives: Metoclopramide is an antagonist of dopamine D2 receptor and is capable of alleviating chemotherapy-induced nausea and vomiting. However, its underlying mechanisms and function in improving the efficiency of chemotherapy are not fully understood. In this study, we investigated the sensitizing effect of metoclopramide on the platinum-based drugs-mediated apoptosis in human head and neck cancer cells.Subjects and Method Apoptosis was analyzed using a cell-based cytometer. The protein expression and messenger ribonucleic acid (mRNA) levels were assessed by Western blotting and real-time polymerase chain reaction, respectively. Results: Metoclopramide sensitized the platinum-based drug (cisplatin and oxaliplatin)-mediated apoptosis in AMC-HN4 cells, but not in normal cells. Mechanistically, we found that metoclopramide decreased Mcl-1 protein expression through post-translational regulation. Moreover, the overexpression of Mcl-1 prevented apoptosis by combined treatment of metoclopramide and platinum-based drugs. Conclusion Metoclopramide induced proteasome-mediated Mcl-1 downregulation, resulting in increased sensitivity to platinum-based drugs.

BACKGROUND/OBJECTIVES: Rosa hybrida has been demonstrated to exert biological effects on several cell types. This study investigated the efficacy of the edible ethanol extract of R.hybrida (EERH) against human colorectal carcinoma cell line (HCT116) cells.MATERIALS/METHODS: HCT116 cells were cultured with different concentrations of EERH (0, 400, 600, 800, and 1,000 µg/mL) in Dulbecco’s modified Eagle medium. Cell viability was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide and viable cell counting assays. Cell cycle pattern was observed by flow cytometry analysis. The wound-healing migration assay, invasion assay, and zymography were used to determine the migratory and invasive level of HCT116 cells treated with EERH. The protein expression and binding ability level of HCT116 cells following EERH treatment were analyzed via immunoblotting and the electrophoretic mobility shift assay. RESULTS: EERH suppressed HCT116 cell proliferation, thus arresting the G1-phase cell cycle.It also reduced cyclin-dependent kinases and cyclins, which are associated with p27KIP1 expression. Additionally, EERH differentially regulated the phosphorylation of extracellular signal-regulated kinase 1/2, c-Jun NH2-terminal kinase, p38, and protein kinase B. Moreover, EERH treatment inhibited the enzymatic activity of matrix metalloproteinase-9 (MMP-9) and MMP-2, resulting in HCT116 cell migration and invasion. The EERH-induced inhibition of MMP-9 and MMP-2 was attributed to the reduced transcriptional binding of activator protein-1, specificity protein-1, and nuclear factor-κB motifs in HCT116 cells. Kaempferol was identified as the main compound contributing to EERH's antitumor activity. CONCLUSION EERH inhibits HCT116 cell proliferation and metastatic potential. Therefore, it is potentially useful as a preventive and curative nutraceutical agent against colorectal cancer.

Background and Objectives: Metoclopramide is an antagonist of dopamine D2 receptor and is capable of alleviating chemotherapy-induced nausea and vomiting. However, its underlying mechanisms and function in improving the efficiency of chemotherapy are not fully understood. In this study, we investigated the sensitizing effect of metoclopramide on the platinum-based drugs-mediated apoptosis in human head and neck cancer cells.Subjects and Method Apoptosis was analyzed using a cell-based cytometer. The protein expression and messenger ribonucleic acid (mRNA) levels were assessed by Western blotting and real-time polymerase chain reaction, respectively. Results: Metoclopramide sensitized the platinum-based drug (cisplatin and oxaliplatin)-mediated apoptosis in AMC-HN4 cells, but not in normal cells. Mechanistically, we found that metoclopramide decreased Mcl-1 protein expression through post-translational regulation. Moreover, the overexpression of Mcl-1 prevented apoptosis by combined treatment of metoclopramide and platinum-based drugs. Conclusion Metoclopramide induced proteasome-mediated Mcl-1 downregulation, resulting in increased sensitivity to platinum-based drugs.

Background and Objectives: Metoclopramide is an antagonist of dopamine D2 receptor and is capable of alleviating chemotherapy-induced nausea and vomiting. However, its underlying mechanisms and function in improving the efficiency of chemotherapy are not fully understood. In this study, we investigated the sensitizing effect of metoclopramide on the platinum-based drugs-mediated apoptosis in human head and neck cancer cells.Subjects and Method Apoptosis was analyzed using a cell-based cytometer. The protein expression and messenger ribonucleic acid (mRNA) levels were assessed by Western blotting and real-time polymerase chain reaction, respectively. Results: Metoclopramide sensitized the platinum-based drug (cisplatin and oxaliplatin)-mediated apoptosis in AMC-HN4 cells, but not in normal cells. Mechanistically, we found that metoclopramide decreased Mcl-1 protein expression through post-translational regulation. Moreover, the overexpression of Mcl-1 prevented apoptosis by combined treatment of metoclopramide and platinum-based drugs. Conclusion Metoclopramide induced proteasome-mediated Mcl-1 downregulation, resulting in increased sensitivity to platinum-based drugs.

Transcription factor CP2-like protein 1 (Tfcp2l1), a naïve pluripotency transcription factor, is expressed in both early embryonic and adult tissues, where it enforces pluripotency of embryonic stem cells (ESCs) and stemness features of cancer cells, respectively. However, the detailed molecular pathways by which Tfcp2l1 is regulated in early embryonic development and cancer cells remain unknown. Here, we identified the pseudophosphatase dual specificity phosphatase 27 (Dusp27), also known as serine/threonine/tyrosine-interacting like-2, as a novel Tfcp2l1-interacting protein through a sterile alpha motif-like domain in the C-terminus of Tfcp2l1 in murine ESCs. The interaction between Dusp27 and Tfcp2l1 was dependent on the cell cycle status and increased during mitosis. Expression of Dusp27 was upregulated during naïve pluripotency and repressed during spontaneous differentiation of murine ESCs. Ectopic expression of Dusp27 enhanced the transcriptional activity of Tfcp2l1 and promoted features associated with the naïve pluripotent state, while suppressing meso-endodermal lineage differentiation. The present study demonstrates that Dusp27 is a novel positive regulator of Tfcp2l1 through a physical interaction and thereby fine-tunes the pluripotency status and meso-endodermal differentiation of murine ESCs.