[Analyses regarding estrogen and estrogen receptors in an experimental osteosarcoma]

Further therapeutical investigations are necessary to obtain a satisfactory survival rate of patients by improving the conventional methods of the treatment of osteosarcoma. Our working hypothesis is that an estrogenic hormonal influence is available for the effective treatment of osteosarcoma. An attempt was made to clarify this idea using experimentally induced hamster osteosarcoma. Male and female Syrian golden hamsters were used. Small amounts of minced tumor pieces were transplanted into hamsters subcutaneously. The levels of the circulating estradiol (E2) and alkaline phosphatase (ALPase) in blood were determined after the transplantation. An estrogen receptor (ER) on tumor cells was also demonstrated. Hamsters with an increased level of serum E2 were likely to have a smaller size of primary tumors and a smaller number of nodes in the lung metastasis. These tumor cells were successfully shown to be positive for ER stain. This suggests that E2 treatment may possibly control the osteosarcoma-condition.