Intra-lesional injection of immunostimulants in bilateral rat tumors

Tumor-inhibitory effect of intralesional injection of bradykinin and immunostimulants in mice

Intralesional injection of bradykinin at the dose of 500 micrograms or 1000 micrograms in oil or gelatin was effective in inhibiting the growth of Sa 180 cells in ddY mice. Ulcer formation in tumor was observed at a high rate in these bradykinin-treated groups. Combined use of bradykinin with a streptococcal preparation (OK-432) was more effective in inhibition of tumor growth compared with that in oil. Similar bradykinin-induced inhibition was observed in a spontaneous mammary tumor of C3H (MM 46) mice. These results suggest that increase in cellular influx and activation of infiltrated cells within a tumor are important factors to induce tumor inhibition effectively.

Further observations on the inhibition of tumor growth by C. parvum with cyclophosphamide. VII. Effect of treatment prior to primary tumor removal on the growth of distant tumor

The present investigations were directed toward determining whether primary tumor manipulation prior to its removal is advantageous for the control of metastases and survival. Studies were carried out to ascertain whether 1) there is justification for delaying surgical removal of a primary tumor to permit preoperative administration of cyclophosphamide (CY) and/or C. parvum (CP) and 2) there is an advantage to administering the immunotherapy directly into a primary tumor. After operation, in all investigations, systemic CP and CY was used. Despite the putative similarity of animals, tumors and treatment regimens there was marked variation in response of tumors to therapy. No benefit was derived from administering preoperative immunotherapy alone. When operation was delayed to employ systemic immuno-chemotherapy, a slight improvement in the control of distant tumor was noted. The employment of preoperative intratumor immunotherapy led to a greater prolongation of survival and more inhibition of distant tumor growth than did immediate primary tumor removal or the use of preoperative systemic immunotherapy. The results suggest that there may be an advantage to delaying removal of a primary tumor so that it may be employed in therapeutic strategies directed toward control of metastatic disease.