Effects of Shark Cartilage on Heterotransplanted Oral Squamous Cell Carcinoma Induced in Nude Mice

The use of shark cartilage as a supplementary treatment has a long yet unresolved history in the realm of complementary-alternative medicine. This study aimed to investigate the impact of concentrated and purified extracts from Persian Gulf shark cartilage (PGSC) on oral cavity squamous cell carcinoma (SCC) (specifically, the KB cell line) induced in an animal model.

Ectopic tumors of oral cavity SCC were induced in eight nude mice through the heterotransplantation of the KB cell line. Once the tumor volume reached 100 mm3, the mice were randomly divided into two groups: treatment and control. The treatment group received shark cartilage at a dosage of 50 mg/kg body weight, while the control group received a phosphate buffer. The drug was administered daily for four days via the intraperitoneal route. Following this, the drug administration was halted for a period of five days before resuming (as per the NCI protocol). After 54 days, the animals were sacrificed, and their tumors were sent for immunohistochemical evaluation using Ki-67 and CD34 markers.

The findings revealed a significant reduction in intratumoral blood vessels in the treatment group compared to the control group (P-value = 0.001). While there was a decrease in both the size of the tumor and the proliferation of tumor cells, this reduction was not statistically significant. The average proliferation index was 13.33% for the treatment group and 33.33% for the control group.

 Significant decrease in intra-tumoral vascularity can control tumor spreading and metastasis, potentially playing an important role in cancer management of oral cavity SCC.