sepantronium and Head-and-Neck-Neoplasms

BACKGROUND YM155, which inhibits the anti-apoptotic protein survivin, is known to exert anti-tumor effects in various cancers. However, there were few reports describing the inhibitory effect of YM155 on human oral squamous cell carcinoma (OSCC) cells that highly express survivin. In this study, we investigated the anti-tumor effects of YM155 on OSCC cells and then examined its molecular mechanisms. MATERIAL AND METHODS SCC9 cells of OSCC were treated with series of concentrations of YM155 (0.01, 0.1, 1, and 10 ng/ml) for 6, 12, and 24 h. The effect of YM155 on survival of SCC9 cells was detected by MTT and colony formation assay. Cell apoptosis was detected by flow cytometric analysis and the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) assays. Western blot was used to detect the protein expression of survivin, p53, and PUMA. Caspase-3 activity was measured by cleavage of the caspase-3 substrate. To test the role of PUMA and caspase-3 on YM155-induced apoptosis and growth inhibition, the SCC9 cells was transfected with PUMA siRNA or caspase-3 siRNA or control siRNA for 16 h before YM155 (1 and 10 ng/ml) treatment for 24 h. In addition, we also investigated the effect of YM155 in an in vivo xenograft model. RESULTS Treatment of YM155 efficiently reduced survivin expression and increased PUMA expression and caspase-3 activation in the SCC9 cells. YM155 treatment resulted in 18-86% decrease in cell viability, 10-60% decrease in colony numbers, and 8-40% increase in cell apoptosis (p<0.05 and p<0.01). However, the induction of cell apoptosis growth inhibition was reversed by PUMA siRNA or caspase-3 transfection. In addition, animals treated with YM155 showed more than 60% tumor growth inhibition compared to the controls (p<0.05). CONCLUSIONS YM155 is a potent inhibitor of progression of SCC9 cells, which could be due to attenuation of survivin, and activation of the PUMA/caspase-3 cellular signaling processes. This study suggests that YM155 may be a potential molecular target with therapeutic relevance for the treatment of OSCC.

Topics: Animals; Apoptosis; Apoptosis Regulatory Proteins; Carcinoma, Squamous Cell; Caspase 3; Cell Line, Tumor; Cell Proliferation; Cell Survival; Down-Regulation; Head and Neck Neoplasms; Humans; Imidazoles; Inhibitor of Apoptosis Proteins; Mice; Mice, Nude; Mouth Neoplasms; Naphthoquinones; Proto-Oncogene Proteins; Squamous Cell Carcinoma of Head and Neck; Survivin; Transcriptional Activation; Xenograft Model Antitumor Assays

The apoptotic activity of methanol extracts of Impatiens balsamina L. (MEIB) and related mechanisms in human oral squamous cell carcinoma (OSCC) cells have been systematically investigated.. The effects of MEIB on human OSCC cell lines were investigated using trypan blue exclusion assay, MTS assay, Western blot, 4'-6-diamidino-2-phenylindole (DAPI) staining, Live/Dead assay, Immunohistochemistry, reverse transcription-polymerase chain reaction, and promoter assay.. MEIB decreased cell viability and induced apoptosis in HSC-4 cells. Higher levels of p-Akt expression were observed in OSCC than in normal oral mucosa (NOM), and it correlated with poor survival of the patients. MEIB dephosphorylated p-Akt and decreased Akt expression through proteasome-dependent degradation. LY294002 (PI3K inhibitor) decreased p-Akt and Akt, resulting in enhancing MEIB-induced apoptosis. MEIB down-regulated the expression level of survivin protein at the transcriptional level and YM155 (survivin inhibitor) decreased survivin, which facilitated MEIB-induced apoptosis. MEIB and LY294002 significantly increased Bax, thereby inducing the conformational change, mitochondrial translocation, and oligomerization. In addition, MEIB-induced growth inhibition and apoptosis in OSC-20, another human OSCC cells were mediated by regulating Akt and it downstream targets, survivin and Bax.. These results suggest that MEIB may serve as a potential drug candidate for the treatment of human OSCC.

Topics: Adult; Antineoplastic Agents, Phytogenic; Apoptosis; Carcinoma, Squamous Cell; Cell Line, Tumor; Chromones; Down-Regulation; Head and Neck Neoplasms; Humans; Imidazoles; Impatiens; Methanol; Molar, Third; Morpholines; Mouth Mucosa; Mouth Neoplasms; Naphthoquinones; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Plant Extracts; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-akt; Squamous Cell Carcinoma of Head and Neck

Survivin is ubiquitously expressed in patients with head neck squamous cell carcinoma (HNSCC) and is associated with poor survival and chemotherapy resistance. Sepantronium bromide (YM155) is a selective survivin suppressant that exhibits potent antitumor activities by inducing apoptosis and autophagy in various types of cancer. However, the curative effects and underlying mechanisms of YM155 in HNSCC remain unclear. This study showed that survivin overexpression positively correlated with p-S6, p-Rb and LAMP2 but negatively correlated with the autophagic marker LC3 in human HNSCC tissues. In vitro studies revealed that YM155 triggered apoptosis of HNSCC cells in mitochondria and death receptor-dependent manner. The treatment also significantly enhanced autophagy by upregulating Beclin1, which led to cell death. YM155 not only downregulated the expression of survivin but also remarkably suppressed the activation of the mTOR signaling pathway in vitro and in vivo. YM155 displayed potent antitumor activities in both CAL27 xenograft and transgenic HNSCC mice models by delaying tumor onset and suppressing tumor growth. Furthermore, YM155 combined with docetaxel promoted tumor regression better than either treatment alone without causing considerable body weight loss in the HNSCC xenograft models. Overall, targeting survivin by YM155 can benefit HNSCC therapy by increasing apoptotic and autophagic cell death, and suppressing prosurvival pathways.

Topics: Animals; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Apoptosis Regulatory Proteins; Autophagy; Beclin-1; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Proliferation; Docetaxel; Drug Resistance, Neoplasm; Head and Neck Neoplasms; Humans; Imidazoles; In Situ Nick-End Labeling; Inhibitor of Apoptosis Proteins; Lysosomal-Associated Membrane Protein 2; Membrane Proteins; Mice; Mice, Knockout; Mice, Nude; Microtubule-Associated Proteins; Mitochondria; Naphthoquinones; Phosphorylation; Retinoblastoma Protein; Signal Transduction; Squamous Cell Carcinoma of Head and Neck; Survivin; Tamoxifen; Taxoids; TOR Serine-Threonine Kinases; Xenograft Model Antitumor Assays

Cisplatin is one of the commonly used chemotherapeutic drugs for the treatment of head and neck squamous cell carcinoma (HNSCC). However, acquisition of cisplatin resistance is common in patients with HNSCC, and it often leads to local and distant failure. In this study, we showed that survivin expression is significantly upregulated in HNSCC primary tumors and cell lines. In addition, survivin levels were significantly higher in human papilloma virus-negative patients that normally respond poorly to cisplatin treatment. Survivin expression was further increased in cisplatin-resistant cells (CAL27-CisR) as compared with its parent cells (CAL27). Therefore, we hypothesized that targeting of survivin in HNSCC could reverse the resistant phenotype in tumor cells, thereby enhancing the therapeutic efficacy of cisplatin. We used both in vitro and in vivo models to test the efficacy of YM155, a small molecule survivin inhibitor, either as a single agent or in combination with cisplatin. YM155 significantly decreased survivin levels and cell proliferation in a dose-dependent manner. In addition, YM155 pretreatment significantly reversed cisplatin resistance in cancer cells. Interestingly, YM155 treatment altered the dynamic localization of survivin in cells by inducing a rapid reduction in cytoplasmic survivin, which plays a critical role in its antiapoptotic function. In a severe combined immunodeficient mouse xenograft model, YM155 significantly enhanced the antitumor and antiangiogenic effects of cisplatin, with no added systemic toxicity. Taken together, our results suggest a potentially novel strategy to use YM155 to overcome the resistance in tumor cells, thereby enhancing the effectiveness of the chemotherapy in HNSCC.

Topics: Adult; Aged; Animals; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Proliferation; Cisplatin; Cytoplasm; Drug Synergism; Female; Head and Neck Neoplasms; Human papillomavirus 16; Humans; Imidazoles; Inhibitor of Apoptosis Proteins; Inhibitory Concentration 50; Male; Mice; Mice, SCID; Middle Aged; Naphthoquinones; Neovascularization, Pathologic; Papillomavirus Infections; Statistics, Nonparametric; Survivin; Tissue Array Analysis; Tumor Burden; Up-Regulation; Xenograft Model Antitumor Assays