Hamster Buccal Pouch Research Articles

DMBA-Induced Oral Carcinoma in Syrian Hamster: Increased Carcinogenic Effect by Dexamethasone Coexposition

Objectives To investigate the effect of systemic administration of the immunosuppressant dexamethasone (DM) while inducing hamster buccal pouch DMBA carcinogenesis. Materials and Methods. Two different experiments were performed. In the first experiment, hamsters' right buccal pouches in group A (n = 10) were painted three times per week with 7,12-dimethylbenzanthracene (DMBA) 0.5%, while pouches of animals in group B (n = 10) were painted three times per week with 7,12-dimethylbenzanthracene (DMBA) 0.5%, while pouches of animals in group B (Results The time of macroscopic neoplasm development was reduced when DM-DMBA coexposition was employed, finding tumors after 10–12 weeks of exposition. In addition, the frequency of histopathological lesions was higher. Conclusion Immunomodulatory action of dexamethasone may reduce the time of oral squamous cell carcinoma (OSCC) induction and may increase the incidence of neoplasms developed.

Tumour preventive potential of sclareol on 7, 12 dimethylbenz [a] anthracene (DMBA) induced hamster buccal pouch carcinogenesis

Sclareol has demonstrated a broad variety of biological activities that belong to the antioxidant anti-inflammatory and anticancer activities that are used in traditional medicine. In the current study, we intended to explore the antitumor possible of sclareol along 7, 12-dimethylbenz (a) anthracene (DMBA) evoked golden Syrian hamster’s buccal pouch carcinogenesis. Lipid peroxidation and antioxidants were assessed by the buccal tissue, and plasma of DMBA evoked golden Syrian hamster buccal pouch carcinogenesis of observational animals. We observed 100% of tumor establishment and noted defects in the biochemical restrictions of lipid peroxidation and antioxidants and also histopathological observations of carcinogenesis in the hamster’s buccal pouch in DMBA only. Sclareol (20 mg/b.wt) has significantly inhibited the tumor burden, tumor volume, and increased phase II detoxification enzymes, antioxidant level, lipid peroxidation, and also phase I enzymes and has improved the histopathologically changes during carcinogenesis in the buccal pouch of DMBA induced golden Syrian hamster. The outcomes of the present scrutinized study proposed that aiming biochemically and histopathologically that act upon the inheritance of cancer characteristics is an effectual system for chemoprevention. Therefore, our results resolved that sclareol has probably owing to its antioxidant or scavenging properties of free radical and transition act on phase I and II enzymes in regards to the evacuation of metabolites carcinogenesis, which is evoked by DMBA in hamster’s buccal pouch.

Efficacy of Hydroxytyrosol as Chemopreventive Agent on Induced Hamster Buccal Pouch Carcinogenesis

ent on induced hamster buccal pouch (HBP) carcinogenesis. Subjects and Methods: Forty Syrian male hamsters five weeks old, weighing 80-120g, were divided into three groups. GI: 10 animals were left untreated. GII: 10 animals were painted with 0.5% 7, 12- dimethylbenz(a)anthracene (DMBA) in paraffin oil, 3 times a week, for 8 weeks (GIIA) and14 weeks (GIIB). GIII: chemoprevention group, 20 animals in which HT was taken at week before as well as during the application of DMBA, 3 times a week on alternative days, for 8 weeks (GIIIA) and14 weeks (GIIIB). HPB mucosa were excised and trimmed to 1-2 cm average size, then processed for hematoxylin and eosin (H&E) stain and Immunohistochemical (IHC) staining utilizing Bcl-2 and Bak antibodies. Results: Gross observation revealed variable changes in the treated (G(s)), (GII and GIII) compared to that observed in GI. Histopathological findings revealed variations among the treated groups. IHC results regarding Bcl-2 expression revealed variability in the area percentage through-out the used groups. GI, GIIA, GIIB, GIIIA and GIIIB were (6.77٪, 31.58٪, 68.37٪, 16.07٪, 48.81٪) respectively, while IHC results regarding Bak expression revealed variability in the area percentage through-out the used groups. GI, GIIA, GIIB, GIIIA and GIIIB were (45.32%, 28.58%, 10.38%, 19.32%, 38.72%) respectively. Conclusion: HT is considered as a promising chemopreventive agent in decrease the incidence of HBP carcinogenesis in gross observation as well as in histological examination.

Astaxanthin inhibits hallmarks of cancer by targeting the PI3K/NF-κΒ/STAT3 signalling axis in oral squamous cell carcinoma models.

Aberrant activation of the PI3K/Akt signalling pathway, a major driving force of diverse cellular processes has been implicated in tumour development and progression. Here, we report that astaxanthin (AXT), a potent antioxidant ketocarotenoid prevents cancer hallmarks by inhibiting PI3K/Akt and the associated downstream NF-κB and STAT-3 signalling pathways in SCC131 and SCC4 oral cancer cells as well as in the hamster buccal pouch carcinogenesis model. Using small molecule inhibitors of NF-κB, STAT-3 and PI3K and by overexpression of PI3K, we provide evidence to show that AXT inhibits NF-κB and STAT-3 signalling and cancer hallmarks by restraining the kinase activity of PI3K/Akt. Additionally, AXT downregulated the noncoding RNAs (ncRNAs), miR-21 and HOTAIR that influence PI3K/Akt signalling emphasising its modulatory effects on epigenetic regulation. Ethyl cellulose-based AXT nanoparticles showed greater chemotherapeutic efficacy in the hamster oral carcinogenesis model compared to native AXT. We suggest that AXT prevents cell proliferation, apoptosis evasion, invasion and angiogenesis by intercepting the crosstalk between the PI3K/Akt, NF-κB and STAT-3 signalling circuits both in vitro and in vivo. Astaxanthin that abrogates the PI3K/Akt signalling axis, a central hub that orchestrates acquisition of cancer hallmarks is a promising candidate for anticancer drug development.

A History of Innovations in the Diagnosis and Treatment of Oral and Head and Neck Cancer

Historical records as far back as 3000 BCE show that oral and head and neck cancer was a disease process well known to Egyptian physicians. Luminaries such as Hippocrates, Galen, Pott, and Virchow were instrumental in shaping our understanding of the etiology and pathogenesis of cancer. During the 20th century, evidence-based medicine catalyzed the development of rigorous science-based diagnostic and treatment protocols. The use of surgery, therapeutic radiation, and chemotherapy as single-treatment agents or in combination with one another gradually emerged as the preferred approach to cancer therapy. The recognition of tobacco, alcohol, and human papillomavirus as etiological agents in oral and head and neck cancer prompted the development of new diagnostic aids and treatment strategies to mitigate cancer progression. More in-depth mechanistic insights into the multistep process of oral and head and neck cancer were made possible by the use of the hamster buccal pouch and mouse models. New technologies, such as the sequencing of the human genome, metabolomics, and proteomics, have provided the foundation for what we today call precision medicine. The future success of tailored medical treatment for cancer patients will depend on the discovery of new druggable targets with improved therapeutic efficacy. As the precision and sensitivity of existing tools for prevention and risk assessment improve, greater accuracy will be achieved in predicting health outcomes.

A trial of thymoquinon loaded on gold nanoparticle as a therapy for induced squamous cell carcinoma in buccal pouch of hamster

Objectives: Combining the anti - tumor effect of thymoquinone (TQ) with the efficient penetration of gold nanoparticles (GNPs) into cells and nuclei as an attempt to treat the induced oral squamous cell carcinoma in buccal pouch of hamster. Materials and methods: This study was carried out on forty two male Syrian golden hamsters (n=42), its age ranged from 6 to 7 weeks, weighting 90-110 gm. Animals were housed with controlled temperature and were given pellets formed of seeds, grain, cracked corn and tap water ad libitum. The hamsters were divided into: Group A: (Control groups) n=24, Group A1: eighteen animals (n=18) were served as “negative control” . Sub-group A1a: Six animals were sacrificed at day zero. Sub-group A1b: Six animals were sacrificed at 14th week. Sub-group A1c: Six animals were sacrificed at 20th week. Group A2: Six animals (n=6) were considered as “positive control”. DMBA was painted to the left cheek pouches, three times /week for 14weeks. Group B: Eighteen animals (n=18) were painted with DMBA to left cheek pouches three times/week for 14weeks, and subdivided into: Sub-group B1: Six animals were injected intra-peritoneal with GNPs/3 times/week for six weeks. Sub-group B2: Six animals were injected intra-peritoneal with TQ/3 times/week for six weeks.Sub-group B3: Six animals were injected intra-peritoneal with GNPs-TQ/3 times/ week for six weeks. All pouches were extracted and prepared to examined through histological examination for any structural changes and immunohistological detection of COX2. Results: Improve superior anti-inflammatory role of TQ when loaded with GNPS in COX-2 retardation and tumor size regression. Conclusion: Thymoquinon loaded on nanogold particle showed protective role in the oral cancer.

Chemopreventive effect of capsaicin in experimentally induced hamster buccal pouch carcinogenesis (Immunohistochemical study Bcl-2)

Aim:To investigate immunohistochemically the effect of chemopreventive capsaicin in epithelial alteration (Epithelial dysplasia) & carcinogenesis which induced in hamsters. Methods: Hematoxylin and Eosin (H&E) and Streptavidin-biotin immunoperoxidase staining techniques was used to detect the expression of Bcl-2 in three groups (G1, G2 and G3). Evaluation of immunostaining was done using computer image analyzer system & statistical analysis. Results: showed that there was a statistically highly significant difference (P G1, G3) (G3>G1). Conclusion:Capsaicin play an important role in reduction and prevention of transformation of epithelial dysplasia into malignant tumor especially oral squamous cell carcinoma. The liquid form of capsaicin may be considered as a new line of treatment in oral dysplasia or even in oral squamous cell carcinoma and the Bcl-2 expression evidenced this reduction of abnormality in epithelial dysplasia.

MAL-PDT inhibits oral precancerous cells and lesions via autophagic cell death.

Oral cancer is a common cancer with a high mortality rate. While surgery is the most effective treatment for oral cancer, it frequently causes deformity and dysfunction in the orofacial region. In this study, methyl aminolevulinate photodynamic therapy (MAL-PDT) as a prevention tool against progression of precancerous lesion to oral cancer was explored. For in vitro studies, we evaluated the effects of MAL-PDT on viability of DOK oral precancerous cells by XTT, cell morphology by TEM, and intracellular signaling pathways by flow cytometry, Western blotting, and immunofluorescence. For in vivo study, DMBA was used to induce oral precancerous lesions in hamsters followed by MAL-PDT treatment. We measured tumor size and body weight weekly. After sacrifice, buccal pouch lesions were processed for H&E stain and immunohistochemistry analysis. MAL-PDT induced autophagic cell death in DOK oral precancerous cells. The autophagy-related markers LC3II and p62/SQSTM1 and autophagosome formation in DOK cells were increased after MAL-PDT treatment. In vivo, Metvix® -PDT treatment decreased tumor growth and enhanced LC3II expression in hamster buccal pouch tumors induced by DMBA. Our in vitro and in vivo results suggest that MAL-PDT may provide an effective therapy for oral precancerous lesions through induction of autophagic cell death.

Stem cell exosomes inhibit angiogenesis and tumor growth of oral squamous cell carcinoma

Recently, exosomes secreted by menstrual mesenchymal stem cells have been identified as inhibitory agents of tumor angiogenesis and modulators of the tumor cell secretome in prostate and breast cancer. However, their direct effect on endothelial cells and paracrine mediators have not yet been investigated. Using a carrier-based cell culture system to test the scalability for exosome production, we showed that different types of endothelial cells present specific kinetics for exosomes internalization. Exosome-treatment of endothelial cells increased cytotoxicity and reduced VEGF secretion and angiogenesis in a dose-dependent manner. Using the hamster buccal pouch carcinoma as a preclinical model for human oral squamous cell carcinoma, we demonstrated a significant antitumor effect of intra-tumoral injection of exosomes associated with a loss of tumor vasculature. These results address up-scaling of exosome production, a relevant issue for their clinical application, and also assess menstrual stem cell exosomes as potential anti-angiogenic agents for the treatment of neoplastic conditions.

Modulating effect of hesperetin on the molecular expression pattern of apoptotic and cell proliferative markers in 7,12-dimethylbenz(a)anthracene-induced oral carcinogenesis

Oral squamous cell carcinoma (OSCC) is widespread malignant neoplasm and refractory cancers in worldwide. Here, we studied the chemopreventive potential of hesperetin on 7,12-dimethylbenz(a)anthracene (DMBA)-induced hamster buccal pouch carcinogenesis (HBPCs). Oral tumours were developed in the buccal pouches of male golden Syrian hamsters by topical application of 0.5% DMBA three times a week for 10 weeks. This causes sequentially hyperplasia, dysplasia and well differentiates squamous cell carcinoma (SCC) with up-regulation of molecular markers like mutant-p53, Caspase-3 and caspase-9 and cyclin-D1. Histology, immunohistochemistry (IHC), real time PCR (qRT-PCR) and western blot analysis of hesperetin treated animals shows a reversal in the above expression pattern to near normal in buccal mucosal tissue. Therefore, hesperetin exhibits the potential protective effect against DMBA-induced oral cancer through apoptotic and anti-proliferative properties. However, a long-term observation would be needed to confirm the possibility of malignant change of the resulted dysplastic lesions upon hesperetin pretreatment.

Glutathione and selenium as chemopreventive agents on experimentally induced hamster buccal pouch epithelial dysplasia

The aim of the present study was directed to investigate the effect of Glutathione (GSH) and Selenium (Se) as chemopreventive agents in experimentally induced hamster buccal pouch (HBP) epithelial dysplasia. Material and methods: Twenty five golden Syrian male hamsters were used as experimental animals and divided into five groups (G1, G2, G3, G4 and G5): G1: 5 animals were left untreated. G2: 5 animals, their right buccal pouches were painted with 0.5% 7, 12 dimethylbenz [a] anthracene (DMBA) 3 times a week for 8 weeks. G3: 5 animals were received GSH one week before, as well as during the application of DMPA for 8 weeks. G4: 5 animals were received Se one week before, as well as during the application of DMPA for 8 weeks. G5: 5 animals were received GSH and Se one week before, as well as during the application of DMPA for 8 weeks. After termination of the experiment, all animals were sacrificed, and the buccal mucosa was excised and preparation in order to be examined histologically and immunohistochemically, then statistical analysis based on these examinations was done Results: Regard to expression of Bcl-2, G2 had recorded the highest mean area percentage (44.25%), while G1 had recorded the lowest mean area percentage (6.73%) and there was high significant difference between G1,G2, G3, G4 and G5 where P value was <0.001, while in regard to expression of Bak, G1 had recorded the highest mean area percentage (41.02%), while G2 had recorded the lowest mean area percentage (19.79%) and there was significant difference between G1, G2, G3, G4 and G5 where P value was 0.019. Conclusion: GSH and Se are considered as promising chemotherapeutic agents in prevention of induced HBP epithelial dysplasia and proved important role in apoptosis and proliferation throughout the process of carcinogenesis.

LOCALIZATION OF CYCLOOXYGENASE-2 IN EXPERIMENTALLY–INDUCED CARCINOGENESIS FOLLOWING TREATMENT WITH THYMOQUINONE LOADED ON NANO-GOLD PARTICLES. (A RETROSPECTIVE STUDY)

Introduction: Thymoquinone is one of the phytochemicals used as chemopreventive agents for oral cancer control. TQ loaded on nanoparticles had shown higher anti-proliferative and anti-inflammatory effects than free TQ. Natural products that can inhibit Cyclooxygenase-2 (COX-2) would be a better choice in the prevention of tumor development with fewer side effects than pharmaceutical agents. Objective: To study the expression of Cox-2 in HBP/DMBA carcinogenesis model following combined topical application of TQ loaded on gold nanoparticles on alternative days. Material and Methods: This research was carried out on archival paraffin blocks of a previous thesis. The paraffin blocks represented hamster buccal pouches (HBPs) from 85 male Syrian golden hamsters were divided into 2 groups. The control groups included: I: negative control group, scarified at day zero then after 7 and 14 weeks, and II: positive control, treated with 7, 12-Dimethylbenz [a]-anthracene (DMBA) for 7 and 14 weeks. The experimental groups included: (III, IV and V) which were treated with the chemopreventive agents for 2 weeks then combined DMBA and the chemopreventive agents on alternative days for 7 and 14 weeks. Sections of 5µm were cut and processed for HE III and IV showed moderate and intense Cox-2 immunoreactivity at 7 and 14 weeks, respectively. Group V showed mild and moderate Cox-2 staining reaction at 7 and 14 weeks, respectively. Conclusion: Topical application of G-NPs-TQ (0.001) for 7 and 14 weeks was able to reduce Cox-2 expression and in turn retard the carcinogenesis process due to its anti-inflammatory effect.

Therapeutic potential of carvacrol on experimentally induced hamster buccal pouch epithelial dysplasia

The aim of the present study was directed to investigate the therapeutic potential of carvacrol on experimentally induced hamster buccal pouch epithelial dysplasia. Material and methods: Seventy golden Syrian male hamsters, five weeks old, weighting 80-120g were divided into three groups(G(s)) GI, GII and GIII. GI (negative control): 10 animals were left untreated. GII: dimethylbenz(a)anthracene (DMBA) induced group): 30 animals were divided into 2 subgroups; GIIA and GIIB. GIIA was painted with 0.5% DMBA in paraffin oil 3 times a week for 8 weeks.GII B was painted with 0.5% DMBA in paraffin oil 3 times a week for 14 weeks. GIII: (carvacrol treated group): 30 animals were divided into 2 subgroups; GIIIA and GIIIB. GIIIA was painted with 0.5% DMBA in paraffin oil 3 times a week for 8 weeks followed by oral administration of carvacrol (15 mg/kg) 3 times a weeks for 6 weeks. GIII B was painted with 0.5% DMBA in paraffin oil 3 times a week for 14 weeks followed by oral administration of carvacrol (15 mg/kg) 3 times a weeks for 6 weeks. Results: Gross observation revealed variation in reduction of the tumor size in the GIII compared to that observed in GII. Histopathological findings in GII revealed variations ranged from moderate dysplasia to well differentiated squamous cell carcinoma while in GIII ranged from mild dysplasia to well differentiated squamous cell carcinoma. Immunohistochemical results revealed that there was highly significant difference between GIIA and GIIIA regarding to Bcl-2, the p value recorded 0.001 (< 0.01) and Bax also showed highly significant difference between the same groups the p value recorded 0.001 (< 0.01). There was highly significant difference between GIIB and GIIIB regarding to Bcl-2, the p value recorded 0.001 (< 0.01) and Bax also showed highly significant difference between the same groups the p value recorded 0.001 (< 0.01). Conclusion: Carvacrol is a novel approach for the treatment of DMBA induced hamster buccal pouch epithelial dysplasia.

Chemopreventive efficacy of carvacrol on experimentally induced hamster buccal pouch carcinogenesis

The aim of the present study was directed to investigate the chemopreventive efficacy of carvacrol on experimentally induced hamster buccal pouch(s) (HBP(s) carcinogenesis utilizing Bcl-2 and Bax as apoptotic markers. Material and methods: Fifty five Syrian male hamsters, five weeks old, weighing 80-120 gm. The animals were divided into three groups (G(s)) (GI, GII and GIII): GI (negative control): 5 animals were left untreated. GII: (DMBA painted group): the right BPs of 20 animals were painted with 0.5% DMBA in paraffin oil 3 times a week on alternative days; they were subclassified into two subgroups (GIIA and GIIB). GIIA: the right BPs of 10 hamsters were painted with DMBA for 6 weeks. GIIB: the right buccal pouches of 10 hamsters were painted with DMBA for 14 weeks. GIII (carvacrol chemoprevention group): 30 hamsters were received carvacrol by the oral route using a specific vehicle in a dose of 15mg/kg; they were subclassified into two subgroups (GIIIA and GIIIB). GIIIA: 15 hamsters were given carvacrol one week before, as well as, during DMBA application for 6 weeks. GIIIB: 15 hamsters were given carvacrol one week before, as well as, during DMBA application for 14 weeks. Results: Gross observation revealed that, there is reduction in the size and distribution of tumors in the GIII compared to that observed in GII. Histopathological findings using H&E stain demonstrated variable changes in the GIII ranging from decrease severity to complete absence of dysplastic features compared to those observed in GII. Immunohistochemical (IHC) results of GIII revealed an increased Bax expression and decreased Bcl-2 expression compared to that observed in GII. Conclusion: The incidence of HBP carcinogenesis was prevented and decreased by oral administration of carvacrol with variable degrees, so it might be considered as a promising chemoprevention agent .The positive effect of carvacrol on apoptosis has been realized, as shown by, increased levels of Bax and decreased levels of Bcl-2 expression during carvacrol chemoprevention, in addition to, highly significantly difference of apoptosis between carvacrol chemoprevention group and DMBA painted group. Keywords: HBP carcinogenesis, carvacrol, apoptosis, DMBA.

Polymethoxyflavones prevent benzo[a]pyrene/dextran sodium sulfate-induced colorectal carcinogenesis through modulating xenobiotic metabolism in ICR mice

Toona sinensis leaf extract (TSL) has been shown to have anti-tumor effects on cancer cell lines. This study aimed to investigate the chemopreventive potential and the underlying mechanism of TSL during 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis.One hundred hamsters were divided into control (n = 30), carcinogenic (n = 20), preventive (n = 42), and therapeutic (n = 8) groups. The animals in carcinogenic and preventive groups were administered reverse osmosis water (carcinogenic group) or TSL (1 g/kg bw) (preventive group) by gavage daily for 4 weeks, and their bilateral pouches were painted with a 0.5% DMBA solution for 4, 9, and 12 weeks. The animals in the therapeutic group were treated with DMBA for 12 weeks prior to TSL administration for 4 weeks. Expression levels of survivin, X chromosome-linked inhibitor of apoptosis (XIAP), proliferating cell nuclear antigen (PCNA), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) proteins were analyzed by immunohistochemistry. Apoptotic activity was examined by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method, cytochrome C, and poly (ADP-ribose) polymerase (PARP).In the preventive group, the results showed significant decreases not only in the incidences of squamous cell carcinoma (SCC) (50%) and epithelial dysplasia (62.5%) but also in the tumor number, tumor volume, tumor burden, and the severity of dysplastic lesions. The down-regulation of survivin, XIAP, PCNA, iNOS, and COX-2 proteins and the increased apoptotic activity indicated anti-proliferative and apoptosis-inducing abilities of TSL on DMBA-induced HBP carcinogenesis.The results suggested that TSL might be a promising candidate for the prevention of oral cancer.

Omics-based analysis of the impact of cigarette smoke and cessation in mouse liver and kidney following a 6-month exposure

Syringic acid (SRA) is an excellent anti-oxidant and anti-cancer property in various in vitro and in vivo studies. In the present study was modifying effect of SRA on 7,12-dimethylbenz(a)anthracene (DMBA) induced cell surface glycoconjugates (GCs) abnormalities in the plasma and buccal mucosa of golden Syrian hamster buccal pouch carcinogenesis (HBPCs). Topical application of DMBA three times a week for 10 weeks on the buccal pouches of the hamsters resulted in well developed squamous cell carcinoma. GCs status was assessed biochemically, histological and immunoexpression pattern of cytokeratin (CK) in the buccal mucosa of the DMBA treated hamsters. Elevated levels of GCs and CK expression were observed in DMBA alone treated hamsters. Oral pre-administration of SRA (50 mg/kg bw) positively modulates the GCs levels and CK expressions to near normal. The present findings suggested that SRA can protect cell surface GCs and CK expression during DMBA induced HBPCs.

Chemoprevention efficacy of indole-3-Carbinol in experimentally induced hamster buccal pouch carcinogenesis

Abstract: The aim of the present study was directed to investigate the effect of indole-3-carbinol (I3C) as a new chemopreventive modality in experimentally induced hamster buccal pouch (HBP) carcinogenesis. Material and methods: Twenty five golden Syrian male hamsters five weeks old, weighting 80-120 gs were used as experimental animals and divided into three group(s) (G(S)) (G1, G2 and G3): G1 (negative control): 5 animals were left untreated. G2: (dimethylbenz[a]anthracene (DMBA) painting-HBP group): 10 animals, their right buccal pouches were painted with 0.5% DMBA in paraffin oil 3 times a week and divided into two subgroups, G2A and G2B (G2A which included 5 animals and painted for 8 weeks, G2B which included 5 animals and painted for 14 weeks. G3 (I3C chemoprevention group): 10 hamsters were included in this group were received I3C given by the oral route using a specific vehicle one week before, as well as during the application of DMPA on alternative days for 8 weeks (G3A) and for 14 weeks (G3B). After termination of the experiment, all animals were sacrificed, and the buccal mucosa was excised and fixed in 10% neutral buffered formalin, routinely processed and embedded in paraffin blocks for preparation in order to be examined histologically and immunohistochemically and then statistical analysis based on these examinations was done Results: Gross observations revealed variable features in (G2 and G3) compared to that observed in group G1ranging from normal and smooth surface to fungating tumor masses of large sizes. Histopathological findings revealed variations among chemoprevention groups ranging from normal epithelial layers to epithelial dysplasia to squamous cell carcinoma with invading nests and pearls. Immunohistochemical (IHC) results, regarding Bax expression, revealed variability in the area percentage throughout the groups used. At 8 weeks, area percentages of G1, G2A, and G3A were (39.83%, 22.00 %, and 30.47 %) respectively, and at 14 weeks were (39.83%, 10.45 % and 26.19%) respectively. Bcl2 expressions also had variability in the area percentage throughout the same groups at 8 weeks were (7.05 %, 43.09 % and 18.15 %) respectively, while at 14 weeks they were (7.05 %, 75.21 %and 43.76 %) respectively. Conclusion: I3C is considered as a promising chemotherapeutic agent in prevention of induced HBP carcinogenesis (epithelial dysplasia & invasive carcinoma) and proved beneficial role in improving the outcome by modulating apoptosis and proliferation throughout the process of carcinogenesis.Keywords: HBP carcinoma, indole-3-carbinol, Bax, Bcl2.

Effect of oxygenated water as a new treatment modality on experimentally induced hamster buccal pouch carcinogenesis

The aim of the present study was directed to investigate the effect of oxygenated water as a new treatment modality on experimentally induced hamster buccal pouch (HBP) carcinogenesis. Material and methods: Eighty-five Syrian male hamsters, five weeks old, weighing 80-120g. The experimental animals were divided into three groups, GI (negative control): 5 animals left untreated. GII {Dimethylbenz[a]anthracene (DMBA) treated group}: 30 animals were painted with 0.5% DMBA in paraffin oil using 3 times a week for 4 weeks (GIIA), 8 weeks (GIIB) and12 weeks (GIIC). GIII (oxygenated water treated group): 45 animals, following each period of DMBA-treatment, were treated in the normal drinking (free access) in addition to once daily obligatory by oral tube for 5 weeks which divided into 3 subgroups GIIIA, GIIIB and GIIIC. Results: Gross observation and histopathological findings revealed a-GI: normal stratified squamous epithelium b- GIIA, GIIIA and GIIIB: mild epithelial dysplasia c: GIIB: moderate and severe epithelial dysplasia d: GIIC and GIIIC: well and moderately differentiated SCC. Immunohistochemical results revealed variable observations among the treated groups (GII and GIII) compared to that observed in group GI. Conclusion: Oxygenated water is considered as a promising treatment agent in preventing of induced HBP carcinogenesis (epithelial dysplasia & invasive carcinoma).

Impact of Whole Plant Extract of Pergularia daemia on Glycoproteins in Dimethylbenz(A)Anthracene Induced Hamster Buccal Pouch Carcinogenesis

Background: Oral squamous cell carcinoma is a major component of a diverse group of neoplasms often referred to as ‘head and neck cancer’. Frequent smoking and/or alcohol consumption are two major risk factors for oral cancer. Objectives: The present study was aimed to investigate the protective role of Pergularia daemia ethyl acetate and methanolic extracts (PDEAE and PDME, respectively) on glycoproteins in dimethylbenz(a) anthracene (DMBA) induced hamster buccal pouch carcinogenesis. Materials and Methods: Male golden Syrian hamsters were used and divided into six groups. Group 2 carried 0.5% 7,12-DMBA painting on left buccal pouch. Groups 3 and 4 were treated with DMBA and 300 mg/kg bwt of PDEAE and PDME by intragastric administration. Remaining groups served as untreated control. All the experiments were performed within 14 weeks. Results: Body weight loss and 100% tumor incidence were observed treated hamsters with DMBA alone, whereas administration of PDEAE and PDME in animals with oral cancer caused significant alterations in body weight and tumor incidence. Further, plasma and buccal pouch tissue glycoprotein levels were increased and erythrocyte glycoprotein levels were depleted in DMBA treated hamsters. The levels were significantly reversed in hamsters treated with PDEAE and PDME at 300 mg/kg bwt. Conclusion: PDEAE and PDME produce a significant protective effect against DMBA induced oral cancer by altering glycoproteins levels.

Effect of esculetin on the expression pattern of apoptotic markers in exper-imental oral carcinogenesis

Evasion of apoptosis has been recognized as one of the salient features of the tumour cell. The programmed cell death is regulated by a spectrum of apoptotic proteins, which include both pro-apoptotic and anti-apoptotic markers. The aim of the present study is to explore the apoptotic induction potential of esculetin by analysing the expression pattern of apoptotic markers in 7,12-dimethylbenz(a)anthracene (DMBA) - induced oral carcinogenesis. Tumours were developed in the hamster’s buccal mocosa using a site- specific carcinogen, DMBA [topical application, 3 times a week for 14 weeks]. While the buccal mucosa from the hamster treated with DMBA alone (tumour bearing hamster) exhibited abnormal pattern of apoptotic markers (p53, Bcl-2, Bax, caspase 3 and caspase 9), the expression pattern was found to be reverted to near normal pattern in DMBA+ esculetin treated hamster’s buccal mucosa. The present results thus reveal the esculetin ability to induce apoptosis in DMBA-induced hamster buccal pouch carcinogenesis. Keywords: Apoptosis, DMBA, Esculetin, Oral cancer