lignans and Mouth-Neoplasms

Magnolia extract (ME) is known to inhibit cancer growth and metastasis in several cell types in vitro and in animal models. However, there is no detailed study on the preventive efficacy of ME for oral cancer, and the key components in ME and their exact mechanisms of action are not clear. The overall goal of this study is to characterize ME preclinically as a potent oral cancer chemopreventive agent and to determine the key components and their molecular mechanism(s) that underlie its chemopreventive efficacy.. The antitumor efficacy of ME in oral cancer was investigated in a 4-nitroquinoline-1-oxide (4NQO)-induced mouse model and in two oral cancer orthotopic models. The effects of ME on mitochondrial electron transport chain activity and ROS production in mouse oral tumors was also investigated.. ME did not cause detectable side effects indicating that it is a promising and safe chemopreventive agent for oral cancer. Three major key active compounds in ME (honokiol, magnolol and 4-O-methylhonokiol) contribute to its chemopreventive effects. ME inhibits mitochondrial respiration at complex I of the electron transport chain, oxidizes peroxiredoxins, activates AMPK, and inhibits STAT3 phosphorylation, resulting in inhibition of the growth and proliferation of oral cancer cells.. Our data using highly relevant preclinical oral cancer models, which share histopathological features seen in human oral carcinogenesis, suggest a novel signaling and regulatory role for mitochondria-generated superoxide and hydrogen peroxide in suppressing oral cancer cell proliferation, progression, and metastasis. Video abstract.

Topics: Animals; Antineoplastic Agents, Phytogenic; Biphenyl Compounds; Cell Line, Tumor; Drug Evaluation, Preclinical; Female; Humans; Lignans; Magnolia; Mice; Mice, Nude; Mitochondria; Mouth Neoplasms; Plant Extracts; Reactive Oxygen Species

Topics: 4-Nitroquinoline-1-oxide; Animals; Antineoplastic Agents, Phytogenic; Apoptosis; Arecoline; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Proliferation; ErbB Receptors; Humans; Lactones; Lignans; Male; Mice, Inbred C57BL; Mouth Neoplasms; Phosphoinositide-3 Kinase Inhibitors

Honokiol, an active natural product derived from Magnolia officinalis, exerted anticancer effects through a variety of mechanisms on multiple types of cancers. In this study, the molecular mechanisms of honokiol in suppressing the human oral squamous cell carcinoma (OSCC) cells were evaluated. Treatment of two OSCC cell lines with honokiol resulted in reducing the cell proliferation and arresting the cell cycle at G1 stage which was correlated with the down-regulation of Cdk2 and Cdk4 and the up-regulation of cell cycle suppressors, p21 and p27. In addition, the caspase-dependent programmed cell death was substantially detected, and the autophagy was induced as the autophagosome formation and autophagic flux proceeded. Modulation of autophagy by autophagic inducer, rapamycin or inhibitors, 3-MA or bafilomycin, potentiated the honokiol-mediated anti-OSCC effects where honokiol exerted multiple actions in suppression of MAPK pathway and regulation of Akt/mTOR or AMPK pathways. As compared to clinical therapeutic agent, 5-FU, honokiol exhibited more potent activity against OSCC cells and synergistically enhanced the cytotoxic effect of 5-FU. Furthermore, orally administrated honokiol exerted effective antitumour activity in vivo in OSCC-xenografted mice. Thus, this study revealed that honokiol could be a promising candidate in preventing human OSCCs.

Topics: Adenine; Animals; Antineoplastic Agents, Phytogenic; Apoptosis; Autophagy; Biphenyl Compounds; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Proliferation; Cyclin-Dependent Kinase 2; Cyclin-Dependent Kinase 4; Cyclin-Dependent Kinase Inhibitor p21; Cyclin-Dependent Kinase Inhibitor p27; Fluorouracil; G1 Phase Cell Cycle Checkpoints; Gene Expression Regulation, Neoplastic; Humans; Lignans; Macrolides; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Mouth Neoplasms; Proto-Oncogene Proteins c-akt; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases; Tumor Burden; Xenograft Model Antitumor Assays

Magnolol, a polyphenol compound from herbal medicines, was shown to alter physiology in various cell models. However, the effect of magnolol on Ca. Cytosolic Ca. Together, in OC2 cells, magnolol induced [Ca

Topics: Biphenyl Compounds; Calcium; Calcium Signaling; Cell Line, Tumor; Cell Survival; Cytosol; Endoplasmic Reticulum; Fura-2; Homeostasis; Humans; Lignans; Manganese; Mouth Neoplasms; Protein Kinase C; Tetrazolium Salts; Type C Phospholipases

Oral squamous cell carcinoma (OSCC) is one of the most common cancers worldwide with poor prognosis. Numerous studies have attempted to explore alternative regimens aimed at reducing cancer stem cells (CSCs) without compromising the efficacy of conventional chemoradiotherapy. The present study sought to assess the effect of a natural compound honokiol on the reduction of elevated cancer stemness, metastatic capacity, and chemoresistance of oral carcinoma stem cells (OCSCs). Our results demonstrated that honokiol attenuated the cell survival and self-renewal of OCSCs in a dose-dependent manner. Moreover, honokiol downregulated the expression of 2 selective markers of OCSCs, ALDH1, and CD44, as well as the migration and invasion abilities, indicating its potential to suppress cancer stemness. We showed that honokiol reduced the secretion of IL-6 and phosphorylation of STAT3, and the honokiol-inhibited self-renewal, invasion and colony formation were reversed by administration of IL-6. Most importantly, our data demonstrated that honokiol was able to potentiate the effect of Cisplatin, leading to a lower proportion of OCSCs and the decreased cancer stemness features. Taken together, this study demonstrated the benefits of utilizing honokiol as an adjunct therapy for OSCC treatment.

Topics: Antineoplastic Combined Chemotherapy Protocols; Biphenyl Compounds; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Survival; Cisplatin; Down-Regulation; Drug Resistance, Neoplasm; Drug Synergism; Humans; Interleukin-6; Lignans; Mouth Neoplasms; Neoplastic Stem Cells; Signal Transduction; STAT3 Transcription Factor

2-O-methylmagnolol (MM1), a derivative of magnolol bearing one methoxy moiety, has been shown to display improved anti-tumor activity against skin cancers. In this study, we examined the anti-tumor effects of magnolol and MM1 on oral squamous cell carcinoma (OSCC).. Trypane blue staining and clonogenic assays were performed to determine the cytotoxic effects of magnolol and MM1 in OSCC cells. Migration and matrigel invasion assays were carried out to examine the metastasis effects of magnolol and MM1 in OSCC cells. IL6-stimulation, Western blot, and immunohistochemistry were used to investigate the IL-6/STAT3 signaling and apoptosis. A bioluminescent mouse model of orthotopically implanted SAS cells was used to determine the anti-tumor activity of MM1 in vivo.. MM1 displays greater activity than magnolol on affecting the cytotoxicity, migration, and invasion of OSCC cells cultured in vitro. The improved anti-tumor activity of MM1 was shown to associate with its greater activity to inhibit STAT3 signaling and to induce apoptosis in the OSCC. In addition, we presented evidence that MM1 is effective in inhibiting the growth of orthotopic implanted OSCC cells in vivo.. Our data indicate that MM1 displays greater anti-tumor activity than magnolol in OSCC and is an attractive agent to be further explored for its potential clinical application.

Topics: Animals; Apoptosis; Biphenyl Compounds; Cadherins; Carcinoma, Squamous Cell; Caspase 3; Cell Line, Tumor; Cell Movement; Cell Proliferation; Humans; Interleukin-6; Lignans; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Mouth Neoplasms; Signal Transduction; STAT3 Transcription Factor; Transplantation, Heterologous; Vimentin

Arecoline, the most abundant alkaloid in betel nut is known to promote abnormal proliferation of epithelial cells by enhancing epidermal growth factor receptor (EGFR) activation and cyclooxygenase-2 (COX2) expression. Taiwanin C, a naturally occurring lignan extracted from Taiwania cryptomerioides, has been found to be a potential inhibitor of COX2 expression. Based on the MTT assay results, taiwanin C was found to be effective in inhibiting the tumorous T28 cell than the non-tumorous N28 cells. The modulations in the expression of relevant proteins were determined to understand the mechanism induced by taiwanin C to inhibit T28 cell proliferation. The levels of activated EGFR and COX2 were found to be abnormally high in the T28 oral cancer cells. However, taiwanin C was found to inhibit the activation of EGFR and regulated other related downstream proteins and thereby inhibited the T28 cell proliferation. In conclusion the results indicate that taiwanin C suppresses COX2-EGFR and enhances P27 pathways to suppress arecoline induced oral cancer cell proliferation via ERK1/2 inactivation. © 2015 Wiley Periodicals, Inc. Environ Toxicol 32: 62-69, 2017.

Topics: 4-Nitroquinoline-1-oxide; Animals; Antineoplastic Agents, Phytogenic; Arecoline; Cell Cycle Proteins; Cell Proliferation; Cyclooxygenase 2 Inhibitors; ErbB Receptors; Lactones; Lignans; Male; MAP Kinase Signaling System; Mice; Mice, Inbred C57BL; Mouth Neoplasms

5-Fluorouracil (5-FU) is an essential chemotherapeutic agent for oral squamous cell carcinoma (OSCC). However, toxic side effects have limited its role in OSCC therapy. The aim of this study was to explore whether combination therapy with 5-FU and honokiol (HNK), a small natural organic molecule shown to induce apoptosis in OSCC cells, could enhance the anticancer activity of 5-FU without notably increasing its toxicity.. 5-FU and/or HNK were used to treat OSCC cells both in vitro and in vivo. The therapeutic effect and underlying mechanisms were evaluated by cell viability assay, flow cytometry, OSCC xenograft mouse model, and Western blot. Tumor tissue apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay. Toxicity was assessed following hematoxylin and eosin staining.. Exposure to HNK + 5-FU produced a synergistic cytotoxic effect on OSCC cells. Both HNK and 5-FU could induce apoptosis through the mitochondria-mediated intrinsic pathway, and their specific signaling pathways were different. In the mouse OSCC xenograft model, treatment with 5-FU + HNK substantively retarded tumor growth, as compared to treatment with either drug individually. TUNEL analysis further confirmed that the superior in vivo antitumor efficacy of 5-FU + HNK was associated with enhanced stimulation of cell apoptosis. Notably, HNK did not increase the toxicity of 5-FU.. These findings suggest that HNK and 5-FU exert a synergistic therapeutic effect on OSCC by inducing apoptosis. HNK might thus enhance the clinical therapeutic efficacy of 5-FU without increasing its toxicity.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Biphenyl Compounds; Carcinoma, Squamous Cell; Cell Line, Tumor; Drug Synergism; Female; Fluorouracil; Humans; Lignans; Mice; Mice, Inbred BALB C; Mouth Neoplasms

Cancer is one of the leading causes of death worldwide, and oral squamous cell carcinoma (OSCC) accounts for almost a sixth of all reported cancers. Arecoline, from areca nut is known to enhance carcinogenesis in oral squamous cells. The objective of this study is to determine the effect of Taiwanin C, from Taiwania cryptomerioides Hayata against Arecoline-associated carcinogenesis. An OSCC model was created in C57BL/6J Narl mice by administrating 0.5 mg mL

Topics: 4-Nitroquinoline-1-oxide; Animals; Arecoline; beta Catenin; Cell Line, Tumor; Cell Movement; Cell Proliferation; Dose-Response Relationship, Drug; Down-Regulation; Enzyme Activation; Gene Expression Regulation, Neoplastic; Glycogen Synthase Kinase 3 beta; Humans; Lactones; Lignans; Mice; Mouth Neoplasms; Signal Transduction; Xenograft Model Antitumor Assays

Topics: Animals; Antineoplastic Agents, Phytogenic; Arecoline; Carcinoma, Squamous Cell; Cell Line, Tumor; Cyclin-Dependent Kinase Inhibitor p27; Cyclooxygenase 2; Dinoprostone; ErbB Receptors; Extracellular Signal-Regulated MAP Kinases; G2 Phase Cell Cycle Checkpoints; Heterografts; Lignans; Male; MAP Kinase Signaling System; Mice, Nude; Mouth Neoplasms; Signal Transduction; Transcription Factor AP-1

Eliminating cancer stem cells (CSCs) has been suggested for prevention of tumor recurrence and metastasis. Honokiol, an active compound of Magnolia officinalis, had been proposed to be a potential candidate drug for cancer treatment. We explored its effects on the elimination of oral CSCs both in vitro and in vivo.. By using the Hoechst side population (SP) technique, CSCs-like SP cells were isolated from human oral squamous cell carcinoma (OSCC) cell lines, SAS and OECM-1. Effects of honokiol on the apoptosis and signaling pathways of SP-derived spheres were examined by Annexin V/Propidium iodide staining and Western blotting, respectively. The in vivo effectiveness was examined by xenograft mouse model and immunohistochemical tissue staining.. The SP cells possessed higher stemness marker expression (ABCG2, Ep-CAM, Oct-4 and Nestin), clonogenicity, sphere formation capacity as well as tumorigenicity when compared to the parental cells. Treatment of these SP-derived spheres with honokiol resulted in apoptosis induction via Bax/Bcl-2 and caspase-3-dependent pathway. This apoptosis induction was associated with marked suppression of JAK2/STAT3, Akt and Erk signaling pathways in honokiol-treated SAS spheres. Consistent with its effect on JAK2/STAT3 suppression, honokiol also markedly inhibited IL-6-mediated migration of SAS cells. Accordingly, honokiol dose-dependently inhibited the growth of SAS SP xenograft and markedly reduced the immunohistochemical staining of PCNA and endothelial marker CD31 in the xenograft tumor.. Honokiol suppressed the sphere formation and xenograft growth of oral CSC-like cells in association with apoptosis induction and inhibition of survival/proliferation signaling pathways as well as angiogenesis. These results suggest its potential as an integrative medicine for combating oral cancer through targeting on CSCs.

Topics: Animals; Antineoplastic Agents, Phytogenic; Apoptosis; Biphenyl Compounds; Cell Proliferation; Gene Expression Regulation, Neoplastic; Humans; Janus Kinases; Lignans; Mice; Mouth Neoplasms; Neoplasm Proteins; Neoplastic Stem Cells; Side-Population Cells; STAT Transcription Factors; Xenograft Model Antitumor Assays

The aim of this study was to investigate anti-inflammatory and anti-cancer effects of honokiol (HK) in two oral squamous cancer cell carcinoma (OSCC) cell lines, HN22 and HSC4, through the regulation of inducible nitric oxide synthase (iNOS) and endoplasmic reticulum resident protein 44 (ERp44). Griess assay, zymography, and quantitative PCR were performed to study iNOS expression and subsequent nitric oxide (NO) production in OSCC cell lines. Liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based proteomic analysis was used to elucidate the proteins associated with ER stress and cellular cytotoxic response induced by HK. Pull-down assay and molecular modeling were performed to better understand how HK interacts with ERp44. In vitro and in vivo experiments in which ERp44 expression was knocked down were performed to better understand the effects of ERp44 on a cellular level and anti-cancer effects of HK. Expression levels of iNOS and subsequent NO secretion were reduced in OSCC cell lines treated with HK. ERp44 was significantly decreased in OSCC cell lines by HK treatment. HK directly bound to ERp44, and ERp44 knock-down significantly inhibited oral cancer cell proliferation and colony formation. Moreover, HK treatment effectively inhibited tumor growth and ERp44 levels in BALB/c nude mice bearing HN22 cell xenografts. Our findings suggest that HK inhibited inflammation and induced apoptosis by suppressing both iNOS/NO and ERp44 expression in HN22 and HSC4 cells and xenograft tumors, and thus could be a potent anti-inflammatory and anti-cancer drug candidate for human oral cancer treatment.

Topics: Animals; Anti-Inflammatory Agents; Antineoplastic Agents; Apoptosis; Biphenyl Compounds; Calcium; Carcinoma, Squamous Cell; Chromatography, Liquid; Humans; Lignans; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Membrane Potential, Mitochondrial; Mice; Mice, Nude; Mouth Neoplasms; NF-kappa B; Nitric Oxide Synthase Type II; Oxidation-Reduction; Tandem Mass Spectrometry; Xenograft Model Antitumor Assays

Recently, biphenolic components derived from the Magnolia family have been studied for anti-cancer, anti-stress, and anti-inflammatory pharmacological effects. However, the pharmacological mechanism of action of 4-O-methylhonokiol (MH) is not clear in oral cancer. The aim of this study was to investigate the role of MH in apoptosis and its molecular mechanism in oral squamous cell carcinoma (OSCC) cell lines, HN22 and HSC4, as well as tumor xenografts. Here, we demonstrated that MH decreased cell growth and induced apoptosis in HN22 and HSC4 cells through the regulation of specificity protein 1 (Sp1). We employed several experimental techniques such as MTS assay, DAPI staining, PI staining, Annexin-V/7-ADD staining, RT-PCR, western blot analysis, immunocytochemistry, immunohistochemistry, TUNEL assay and in vivo xenograft model analysis. MH inhibited Sp1 protein expression and reduced Sp1 protein levels via both proteasome-dependent protein degradation and inhibition of protein synthesis in HN22 and HSC4 cells; MH did not alter Sp1 mRNA levels. We found that MH directly binds Sp1 by Sepharose 4B pull-down assay and molecular modeling. In addition, treatment with MH or knocking down Sp1 expression suppressed oral cancer cell colony formation. Moreover, MH treatment effectively inhibited tumor growth and Sp1 levels in BALB/c nude mice bearing HN22 cell xenografts. These results indicated that MH inhibited cell growth, colony formation and also induced apoptosis via Sp1 suppression in OSCC cells and xenograft tumors. Thus, MH is a potent anti-cancer drug candidate for oral cancer.

Topics: Aged; Aged, 80 and over; Animals; Antineoplastic Agents, Phytogenic; Apoptosis; Biphenyl Compounds; Carcinoma, Squamous Cell; Cell Survival; Female; Gene Expression; Humans; Inhibitory Concentration 50; Lignans; Male; Mice, Nude; Middle Aged; Mouth Neoplasms; Neoplasm Transplantation; Sp1 Transcription Factor

To observe arctigenin's inhibitory effect on oral squamous cell carcinoma, and explore the possible mechanism.. The expression of VEGF in 32 cases of oral squamous cell cancer and 20 adjacent tissue specimen were detected with immunohistochemistry. Human nude mouse transplantation tumor model of oral squamous cell cancer was prepared with HSC-3 cells line. Transplanted tumor growth and VEGF expression in transplanted tumor tissues were assayed after treatment with arctigenin. One-way ANOVA was used for comparison between groups with SPSS 16.0 software package.. Compared with the adjacent tissue, immunohistochemical staining score of VEGF was significantly higher (P<0.01) in oral squamous cell carcinoma tissues. After treatment with arctigenin, the growth of oral squamous cell transplanted tumors in nude mouse was inhibited (P<0.05), and decreased weight in end point of observation was noted (P<0.05). There were significant differences between high dose group and low dose group (P<0.05). Compared with the nude mouse model group, the optical density of VEGF staining was significantly lower in arctigenin group (P<0.05). There were significant differences between high dose group and low dose group (P<0.05).. Arctigenin can dose-dependently inhibit the growth of oral squamous cell carcinomas, and this effect may be related to down regulation of VEGF expression.

Topics: Animals; Antineoplastic Agents; Carcinoma, Squamous Cell; Down-Regulation; Furans; Humans; Immunohistochemistry; Lignans; Mice; Mice, Nude; Mouth Neoplasms; Neoplasm Transplantation; Vascular Endothelial Growth Factor A

Honokiol (HK), a novel plant-derived natural product, is a physiologically activated compound with polyphenolic structure, and has been identified to function as an anticancer agent. It has been widely used in several diseases as a traditional medicine for a long time. We investigated whether HK could show anticancer effects on two oral squamous cell lines (OSCCs), HN-22 and HSC-4. We demonstrated that HK-treated cells showed dramatic reduction in cell growth and apoptotic cell morphologies. Intriguingly, the transcription factor specificity protein 1 (Sp1) was significantly inhibited by HK in a dose-dependent manner. Furthermore, we checked changes in cell cycle regulatory proteins and anti-apoptotic proteins at the molecular level, which are known as Sp1 target genes. The important key regulators in the cell cycle such as p27 and p21 were up-regulated by HK-mediated down-regulation of Sp1, whereas anti-apoptotic proteins including Mcl-1 and survivin were decreased, resulting in caspase-dependent apoptosis. Taken together, results from this study suggest that HK could modulate Sp1 transactivation and induce apoptotic cell death through the regulation of cell cycle and suppression of anti‑apoptotic proteins. In addition, HK may be used in cancer prevention and therapies to improve the clinical outcome as an anticancer drug.

Topics: Antineoplastic Agents; Apoptosis; Biphenyl Compounds; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Proliferation; Down-Regulation; Gene Expression Regulation, Neoplastic; Humans; Lignans; Mouth Neoplasms; Plants; Sp1 Transcription Factor

Honokiol (HNK) is a small organic molecule purified from magnolia species and has demonstrated anticancer activities in a variety of cancer cell lines; however, its effect on oral squamous cell carcinoma (OSCC) cells is unknown. We investigated the antitumor activities of HNK on OSCC cells in vitro for the first time. The inhibitory effects of HNK on the growth and proliferation of OSCC cells were demonstrated via in vitro 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and propidium iodide (PI) assays, and the apoptotic cells were investigated by the observation of morphological changes and detection of DNA fragmentation via PI, TdT-mediated dUTP-biotin nick end labeling (TUNEL), and DNA ladder assays, as well as flow cytometry assay. The results showed that HNK inhibited the growth and proliferation of OSCC cells in vitro in a time and dose-dependent manner. The inhibitory effect was associated with the cell apoptosis induced by HNK, evidenced by the morphological features of apoptotic cells, TUNEL-positive cells and a degradation of chromosomal DNA into small internucleosomal fragments. The study also demonstrated here that the inhibition or apoptosis mediated by 15 microg x mL(-1) or 20 microg x mL(-1) of HNK were more stronger compared with those of 20 microg x mL(-1) 5-fluorouracil (5-Fu, the control) applied to OSCC cells, when the ratio of OSCC cell numbers were measured between the treatment of different concentrations of HNK to the 5-Fu treatment for 48 h. HNK is a promising compound that can be potentially used as a novel treatment agent for human OSCC.

Topics: Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Biphenyl Compounds; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Proliferation; Cell Survival; Drugs, Chinese Herbal; Flow Cytometry; Fluorouracil; Humans; In Situ Nick-End Labeling; Lignans; Magnolia; Mouth Neoplasms; Phytotherapy; Plant Extracts