melphalan and Carcinoma--Lewis-Lung

Previous research in our laboratories has shown that the immunoregulatory octapeptide, THF-gamma 2, potentiates the efficacy of anticancer chemotherapy in experimental animal models of local plasmacytoma and repairs drug-induced defects in immunocompetence. The highly metastatic, murine D122 lung carcinoma model has been shown to be useful for evaluating the efficacy of experimental antimetastatic therapeutic modalities. The goal of the present study was to determine whether intranasal thymic humoral factor-gamma 2 (THF-gamma 2) immunotherapy, after a single dose of chemotherapy, could inhibit the development of lung metastases, restore immunocompetence, and increase survival in syngeneic C57BL/6 mice bearing highly metastatic Lewis lung carcinoma (D122) solid footpad tumors. Relative to untreated mice and those receiving chemotherapy alone, mice receiving combined chemoimmunotherapy showed the following significant differences: (a) decreased lung metastatic load as assessed by lung weight, (b) prolonged survival time, (c) massive infiltration of lymphoid cells in the lungs, and (d) restoration of impaired immune parameters to normal values in melphalan-treated mice. THF-gamma 2 prevented tumor emboli from colonizing the target tissue, probably by inducing expansion of the lymphoid cell compartment. When used as an adjunct to anticancer chemotherapy, intranasal THF-gamma 2 immunotherapy is a simple and safe treatment modality that seems to be promising for inhibiting lung metastases.

Topics: Adjuvants, Immunologic; Administration, Intranasal; Animals; Carcinoma, Lewis Lung; Combined Modality Therapy; Female; Fluorouracil; Immunotherapy, Active; Lung; Lung Neoplasms; Male; Melphalan; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Oligopeptides; Organ Size; Spleen; Survival Analysis; T-Lymphocyte Subsets; Thymus Hormones

Although the antiangiogenic agent TNP-470 does not, in general, increase the cytotoxicity of anti-cancer therapies in cell culture, the antiangiogenic agents TNP-470 and minocycline individually and especially in combination have been shown to increase the tumor growth delay produced by several standard cytotoxic therapies in the Lewis lung carcinoma. In an effort to understand the mechanism by which the antiangiogenic agent combination TNP-470/minocycline potentiates the antitumor activity of cytotoxic therapeutic agents in vivo, the biodistribution of [14C]-cyclophosphamide and cis-diamminedichloroplatinum(II) was determined 6 h after cytotoxic drug administration in animals bearing Lewis lung carcinoma pretreated with TNP-470/minocycline and in animals without pretreatment. Higher levels of 14C and platinum were found in 9 tissues (including tumor) except blood in animals pretreated with TNP-470/minocycline. The increased drug levels in the tumors may be sufficient to account for the increased tumor growth delays observed previously. DNA alkaline elution of tumors from animals pretreated with TNP-470/minocycline showed increased DNA cross-linking by both cyclophosphamide and cis-diamminedichloroplatinum(II). The possible implications of these results are discussed.

Topics: Animals; Antineoplastic Agents; Carcinoma, Lewis Lung; Carmustine; Cell Hypoxia; Cell Survival; Cisplatin; Cyclohexanes; Cyclophosphamide; DNA, Neoplasm; Drug Combinations; Male; Melphalan; Mice; Mice, Inbred C57BL; Minocycline; O-(Chloroacetylcarbamoyl)fumagillol; Platinum; Sesquiterpenes; Tumor Cells, Cultured

CAI (NSC 609974; L651582), a new agent that has demonstrated antimetastatic activity in vitro and in vivo, was not very cytotoxic toward EMT-6 mouse mammary carcinoma cells in culture or toward FSaIIC fibrosarcoma cells in vivo. Coexposure of EMT-6 cells to CAI and antitumor alkylating agents under various environmental conditions did not markedly increase the cytotoxicity of cisplatin (CDDP), melphalan, or carmustine (BCNU). However, the combination of CAI and 4-hydroperoxycyclophosphamide (4-HC) produced much greater than additive killing of EMT-6 cells. CAI also increased the sensitivity of hypoxic EMT-6 cells to X-rays. CAI increased the cytotoxicity of cyclophosphamide toward FSaIIC tumor cells when animals were treated with single doses of both drugs. The effect of CAI on tumor cell killing by cyclophosphamide was greatest at high doses of the antitumor alkylating agent. CAI administration appeared to result in increased serum levels of prostaglandin E2 and leukotriene B4 in animals bearing the Lewis lung tumor. Administration of CAI on days 4-18 did not alter the growth of the Lewis lung carcinoma but did result in an increase in the tumor-growth delay produced by treatment with CDDP, cyclophosphamide, melphalan, BCNU, and fractionated radiation. Although CAI did not reduce the number of lung metastases present in Lewis lung carcinoma-bearing mice on day 20, it did appear to reduce the number of large (vascularized) metastases present on that day.

Topics: Aminoimidazole Carboxamide; Animals; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Lewis Lung; Carmustine; Cisplatin; Cyclophosphamide; Fibrosarcoma; Mammary Neoplasms, Experimental; Melphalan; Mice; Triazoles; Tumor Cells, Cultured