INTRODUCTION: Oral squamous cell carcinoma (OSCC) has the highest mortality rates among all carcinomas and is the most common head and neck cancer. Several natural compounds and micronutrients have been under investigation for their efficacy in head and neck cancer chemoprevention. Green tea contains various cancer preventive catechins that have a role in preventing cancer recurrence in various organs in humans. Curcumin, a natural polyphenol, is one of the most investigated biomolecules from Mother Nature. Curcumin has been shown to exert significant growth inhibitory effect on oral precancerous and carcinoma cell lines, and the effect is synergistic with epigallocatechin gallate, the most abundant polyphenol in tea. OBJECTIVES: To assess the chemopreventive effects of green tea and curcumin through induction of hamster buccal pouch carcinoma by using an apoptotic marker and compare their effect each alone and in combination. MATERIALS AND METHODS: Squamous cell carcinoma was chemically induced in fifty Syrian golden hamsters divided into 5 groups (10 each). The first group was used as normal control group. The second group received the carcinogenic agent only. The other three groups received green tea, curcumin and combination of both, respectively. RESULTS: Normal control group (A) revealed neither pathological nor inflammatory changes in the buccal pouch with 1.72% of the cells underwent apoptosis while the cells of positive control group (B) resulted in 11.57% apoptosis. In the study groups, treatment of the cells with green tea (C), curcumin (D) and both of them (E) resulted in 82.22 %, 78.91%, 96.63% apoptosis respectively. The fluorescent image by confocal laser scanning in group B showed increase of the red fluorescence in the nucleus and cytoplasm of the squamous cell carcinoma cells indicating high proliferating cells while the fluorescent image of group C, D and E showed decrease of the red florescence in the nuclei of the squamous cell carcinoma cells indicating low proliferation. CONCLUSIONS: Green tea and curcumin have a significant chemopreventive effect against oral carcinogenesis and the combination of both agents has a better effect.

Introduction Chemoprevention refers to using specific substances during oncogenesis. Curcumin and catechins are both polyphenol types of phytochemicals present in curcuma longa and green tea. The effect of curcumin is synergistic with epigallocatechin gallate, the most abundant polyphenol in tea. Aim To evaluate and compares the chemopreventive effect of both green tea and curcumin (each individually and in combination) through induction of hamster buccal pouch carcinoma. Materials and methods Squamous cell carcinoma was chemically induced in fifty Syrian golden hamsters divided into 5 groups (10 each). The first group was used as a normal control group. The second group received the carcinogenic agent only. The other three groups received green tea, curcumin, and a combination of both, respectively. Flow cytometry, immunofluorescence, and immunohistochemical assays were used to evaluate apoptosis, proliferation, and angiogenesis. ANOVA test was used to analyze the results between the study groups. Results The cells of the positive control group (B) resulted in 11.57% apoptosis. In the study groups, treatment of the cells with green tea (C), and curcumin (D) and both of them (E) showed increased apoptosis. The fluorescent image in group B showed an increase of the red fluorescence in the nucleus and cytoplasm of the squamous cell carcinoma cells while groups C, D, and E showed a decrease of the red fluorescence in the nuclei of the squamous cell carcinoma cells. The microvessel density was higher in the positive control group as compared to the treated groups. Conclusions The combination of green tea and curcumin has a significant chemopreventive effect against oral carcinogenesis.

INTRODUCTION:Myofibroblasts are modified fibroblasts that express features of smooth muscle differentiation. These cells play a key role in physiologic and pathologic processes such as wound healing and tumorigenesis, respectively. Tumor cells work in close coordination with stromal elements from its stage of emergence to metastasis. Myofibroblasts are important stromal cells that play a crucial role in carcinogenesis due to its ability to modify the extracellular matrix. Alpha smooth muscle actin (α-SMA) is regarded as the most widely used biomarker for identifying myofibroblasts. The presence of myofibroblasts has been demonstrated in various malignant lesions. However, the number of studies evaluating their role in oral squamous cell carcinoma (OSCC) remains limited. OBJECTIVES: The present study aimed to assess the presence and distribution patterns of myofibroblasts in OSCC primary tissues according to histological grade, as well as to determine its correlation with metastasis in regional lymph nodes (LNs). MATERIAL AND METHODS: Immunohistochemical study using the α-SMA antibody was done on 30 OSCC cases (15 cases with LN metastasis and 15 cases without LN metastasis) and 15 normal oral mucosal tissues. RESULTS: Most of OSCC tissues showed positive immunoreactivity to α-SMA, while normal tissues were immune-negative. The expression of α-SMA was significantly higher in the OSCC with LN metastasis than OSCC without LN metastasis (P < 0.05). Conversely, there was no significant correlation with the histological grades of OSCC. CONCLUSION: α-SMA could be used as a monitory marker in OSCC.