Effect of thermochemotherapy on the development of spontaneous lung metastases

Abstract

Effect of local hyperthermia given alone or in combination with cyclophosphamide and/or hyperglycaemia on the development of lung metastasis was studied using a non-immunogenic mouse fibrosarcoma, FSa-II. Incidence of lung metastasis was dependent upon the tumour size, and was increased when tumour-bearing mice were restrained in animal holders which were used for heat-treatment of animal tumours. The frequency of the metastatic spread was decreased following local hyperthermia at 41.5 degrees and 45.5 degrees C when compared to that following sham treatment. This decrease was independent of the heat dose. Similar reduction in the incidence of metastasis was observed after hyperthermia given following glucose administration. The administration of cyclophosphamide effectively inhibited the development of lung metastasis. However, the magnitude of the inhibition was identical to that following hyperthermia alone. In conclusion, hyperthermia given alone, or in combination with hyperglycaemia or cyclophosphamide, inhibited the development of lung metastasis.

Patterns of heat shock protein (HSP70) expression and Kupffer cell activity following thermal ablation of liver and colorectal liver metastases

“…Cells with increased baseline HSP levels exhibit greater thermoresistance and are afforded additional protection from protein loss [45]. Increased expression of HSPs in surviving tumour cells at the margins of thermal ablated tumours may lead to the development of more malignant and heat resistant tumour strains [46,47].…”

Mechanisms of Focal Heat Destruction of Liver Tumors

“…Cells with increased baseline HSP levels are afforded added protection from protein loss and exhibit greater thermoresistance [93]. Increased expression of these proteins in surviving tumor cells following focal hyperthermia may lead to the progressive development of more malignant and heat resistant tumor strains [94].…”

Combined Effect in vitro of Chemotherapy with Agents Acting on the Cell Membrane of Lewis Lung Carcinoma

“…Augmented effects of various cytotoxic agents by hyperthermia have been found by many authors in numerous tumor sys tems [19][20][21][22][23]. Several recent studies have shown an increased antineoplastic activity of cytotoxic agents in conjunction with calcium channel blockers.…”

“…One of the mechanisms of the antineoplastic effect of hyperthermia is an action on the cell membrane [10][11][12][13][14][15][16][17][18]. Hy perthermic treatment has been found to enhance the inhibitory effects of various cytotoxic agents on different tumors [19][20][21][22][23]. Verapamil acts on the cell mem brane as a calcium channel blocker [24][25][26], Increased activity of antitumoral cytotoxic agents in the presence of calcium antagonists has been reported [27][28][29][30][31][32][33][34][35].…”