maltose-tetrapalmitate and Prostatic-Neoplasms

Maltose tetrapalmitate (MTP), a synthetic nontoxic immunoadjuvant, the radiosensitizer misonidazole (MISO), and 60Co gamma-radiation, alone or in combination, were used in the management of Dunning prostatic tumor in the rat. Nine groups of 10 rats each were used to assess the efficacy of various therapeutic modalities. Tumor growth rates and animal survival times were determined for each group. Radiation was more effective when combined with MTP, but the adjuvant must be present when radiation is given for synergism to occur. MISO was as effective as MTP when used with radiation, but combining them cancels out their individual effects. In a clinical situation it would be advantageous to use separately the synergisms existing between MISO and radiation on the one hand and MTP and radiation on the other hand.

Topics: Adjuvants, Immunologic; Animals; Antineoplastic Agents; Cobalt Radioisotopes; Combined Modality Therapy; Glycolipids; Male; Misonidazole; Nitroimidazoles; Prostatic Neoplasms; Rats

Chemoimmunotherapy in two animal models for urological cancers was studied. The models were Dunning R3327A prostatic carcinoma transplanted s.c. in Fischer X Copenhagen F1 hybrids and a well-differentiated bladder carcinoma transplanted orthotopically in the bladder submucosa of female Fischer rats. Cyclophosphamide, cis-platinum, and Adriamycin were initially used as anticancer chemotherapeutic agents, and the most effective ones were used in combination with maltose tetrapalmitate (MTP), which was used as an immunopotentiator. In the case of prostatic carcinoma, cyclophosphamide was the most effective among the anticancer agents in controlling tumor growth after inoculation of either 10(4) or 10(5) tumor cells. Combination of cyclophosphamide with i.p. MTP delayed tumor take and controlled tumor size more effectively than did either of the treatments given alone. Similar results were obtained in the case of bladder tumor. A combination of cis-platinum with MTP significantly controlled bladder tumor size, and a combination of cyclophosphamide with MTP cured 75% of the rats. The remaining 25% of this group had a small tumor that did not increase in size during the subsequent 2 weeks of observation without treatment. The incidence of metastasis of bladder tumor to lymph nodes and lung was reduced by MTP and cis-platinum and eliminated by cyclophosphamide alone and in combination with MTP. Nonspecific immunity as measured by phytohemagglutinin stimulation of spleen lymphocytes and antitumor immunity as measured by cytotoxicity and macrophage migration inhibition assays were highest in rats subjected to cyclophosphamide and MTP combined therapies.

Topics: Animals; Antineoplastic Agents; Cisplatin; Cyclophosphamide; Doxorubicin; Drug Therapy, Combination; Female; Glycolipids; Immunity, Cellular; Immunotherapy; Male; Neoplasm Transplantation; Prostatic Neoplasms; Rats; Urinary Bladder Neoplasms

The effectivenss of maltose tetrapalmitate (MTP) as an antitumour immune adjuvant was verified by its comparison with other known immunopotentiators, namely BCG, Corynebacterium parvum, levamisole and pyran copolymer. Copenhagen x Fisher 344/CRBL F1 hybrid male rats inoculated s.c. with the Dunning R3327A prostatic adenocarcinoma were used as the test system. All animals treated with immunoadjuvants showed a delay in tumour appearance and inhibition of early tumour growth. MTP was found to be the most effective, followed by levamisole, BCG, pyran copolymer and C. parvum in order of decreasing efficacy. Intratumoral treatment of small or large s.c. tumours with BCG, MTP and C. parvum was ineffective in our cases. However, this treatment was effective with MTP and BCG if they were used against a differentiated form of R3327 tumour. MTP and levamisole were found to be equally effective when given orally in drinking water. Experiments involving surgical excision of tumours followed by MTP therapy in two s.c. implanted animal tumour models (viz. a poorly immunogenic ascites mammary carcinoma 13762 in Fisher 344/CRBL rats, and an SV40 virus-induced sarcoma of low immunogenicity in Syrian hamster) showed beneficial effects of MTP on local tumour recurrence and tumour growth. Pre- and postoperative MTP treatment was at least as effective as postoperative MTP treatment alone.

Topics: Adenocarcinoma; Adjuvants, Immunologic; Animals; Bacterial Vaccines; BCG Vaccine; Dose-Response Relationship, Immunologic; Glycolipids; Levamisole; Male; Maltose; Neoplasm Recurrence, Local; Neoplasms, Experimental; Palmitates; Postoperative Period; Propionibacterium acnes; Prostatic Neoplasms; Rats; Rats, Inbred Strains