GENDER INFLUENCES TUMOR-GROWTH IN A MODEL OF HUMAN ORAL SQUAMOUS-CELLCARCINOMA

The pattern of tumour growth was investigated using our unique syngene ic animal model of human oral squamous cell carcinoma of the head and neck (SCCHN). Gender-conditioned tumour fragments of near equal size w ere transplanted into recipient animals and the pattern of tumour grow th was assessed by monitoring tumour size in vivo and/or the weight of tumour al termination of the experiment. Our results confirmed the ep ithelial nature of tumour cells on fresh tumour tissue sections using morphological and immunocytochemical examination. The mean weights of tumour per animal (n=10) after transplant from female (F) to F recipie nts, and across and between same gender showed differences if the anim als were sexually mature. The results indicated an endocrine sensitive (sex hormone) component of tumour growth. In separate experiments, th e recipient animals were immunised with a mechanically dissociated sin gle cell suspension from fresh tumour after irradiation (500 cGys). Th e test,group (n=5) and control group (n=5, saline injected) animals re ceived tumour fragments by grafting and following a Eur ther three wee ks post immunisation, the tumours were removed and weighed. The test a nd control groups were different with a p-value of 0.001, suggesting a n immune participation in the growth of this tumour. The results, take n together, thus suggest the participation of both the endocrine and t he immune systems on the pattern of tumour growth in this animal model . The possible clinical relevance of these results is discussed.