Investigation Of Anti-Tumour Activity Of Orthosiphon Stamineus On Human Oral Squamous Cell Carcinoma

Introduction: Oral Cancer contributes to 1.11% of total deaths in Malaysia, with 1,865 cases reported in 2020. In this study, the standardized extract of NuvastaticTM (C5OSEW5050ESA) showed antitumor activity in oral cell carcinoma in vitro and in vivo. The active ingredient of NuvastaticTM is derived from a standardized extract of Orthosiphon stamineus based on 6% rosmarinic acid Objective: The present study was conducted to evaluate the anticancer potential of C5OSEW5050ESA OS against human oral squamous cell carcinoma (CAL27) ectopically implanted into Nu/Nu nude mice. Methods: The cytotoxicity of C5OSEW5050ESA OS against human oral squamous cell carcinoma CAL27) was evaluated using the MTT assay. The antitumor activity of C5OSEW5050ESA OS was performed by ectopically implanting CAL27 cells into athymic NCR Nu/Nu nude mice. The diseased animals were treated with 200 and 400mg/kg C5OSEW5050ESA OS daily for 3 weeks. Result: The study showed that C5OSEW5050ESA was weakly cytotoxic against CAL27 with an IC50 of 899.2 μg/ml. At a dose of 200 and 400 mg/kg, compound C5OSEW5050ESA showed significant anti-tumor effect in xenograft cancer model. C5OSEW5050ESA showed a dose-dependent suppression of oral cancer growth with 74.1.1±1.1 and 81.7±2.1% compared to the negative control group at 200 mg/kg and 400 mg/kg, respectively. In addition, the cancer growth of the positive control (imatinib) treated animals showed that the size of cancer growth reduced significantly with 52.4±2 compared to the negative control (untreated) group. Conclusion: The result of this study highlights the potential of NuvastaticTM in the treatment of oral squamous cell carcinoma.