Effect of hyperthermia in vitro and in vivo on adenine and pyridine nucleotide pools in human peripheral lymphocytes

Ifosfamide, carboplatin and etoposide combined with 41.8 degrees C whole body hyperthermia for malignant pleural mesothelioma

We performed a phase II study combining 41.8 degrees C whole body hyperthermia with ICE chemotherapy, i.e. ifosfamide (5 g/m(2)), carboplatin (300 mg/m(2)) and etoposide (150 mg/m(2) on days 2 and 3), administered every 4 weeks, for patients with malignant pleural mesothelioma. Of 27 chemonäive, non-metastatic patients enrolled, 25 patients were evaluable for response. Overall response rate was 20% (five partial remissions; 95% CI 8.9-39.1%). Median survival time from the start of treatment for all patients was 76.6 weeks (95% CI 65.4-87.8 weeks). Progression free survival for all patients measured 29.6 weeks (95% CI 24.4-34.7 weeks). One year overall survival was 68% and 2 year overall survival was 20%. Major treatment toxicities included grade 3/4 neutropenia and thrombocytopenia in 74 and 33% of treatment cycles, respectively. One patient died due to sepsis. These promising results are consistent with continued clinical investigation; a phase III clinical trial with whole body hyperthermia as the independent variable has been initiated.

A pilot study of whole body hyperthermia and carboplatin in platinum-resistant ovarian cancer

The aim of this study was to determine whether the addition of whole body hyperthermia (WBH) to carboplatin (CBDCA) can induce responses in patients with platinum-resistant ovarian cancer. 16 pretreated patients with platinum-resistant ovarian cancer were entered on a Systemic Hyperthermia Oncological Working Group (SHOWG) study; (14 patients were eligible with 14 evaluable for toxicity and 12 for response). The patients were treated with WBH (Aquatherm) 41.8 degrees C x 60 min in combination with carboplatin (CBDCA) (area under the curve (AUC) of 8) every 4 weeks. Disease status was evaluated every two cycles. Patients were treated for a maximum of six cycles. One patient had a complete response (CR) and 4 had a partial response (PR). 4 patients had stable disease (SD). 3 patients had progressive disease (PD). 2 patients were unevaluable: 1 had a bowel obstruction shortly after her first treatment; the second patient achieved a CR, but only had one treatment secondary to an idiosyncratic reaction to sedative drugs. 2 patients entered on study were ineligible, as they did not meet criteria for platinum resistance; 1 entered a CR and 1 had SD. Dose-limiting toxicity, which required CBDCA dose reductions, was grade 4 thrombocytopenia. Other toxicities included neutropenia (grade 3/4), and nausea and/or vomiting. Consistent with preclinical modelling, these results suggests that 41.8 degrees C WBH can overcome platinum resistance in ovarian cancer. These observations suggest further investigation of the therapeutic potential of WBH in a group of patients who historically fail to respond to salvage therapies is warranted.

Enzyme activities leading to NAD synthesis in human lymphocytes

Pyridine nucleotide levels and the activities of enzymes involved in NAD synthesis (nicotinic acid phosphoribosyltransferase, nicotinic acid- and nicotinamide mononucleotide-adenylyltransferase) have been assayed in human normal lymphocytes by an HPLC method using radioactive or nonradioactive substrates. NAD concentration was 46.4 +/- 17.2 pmol 10(-6) cells, and that of NADP was 14.5 +/- 3.9 pmol 10(-6) cells (mean +/- standard deviation). The adenylyltransferase activity using nicotinic acid mononucleotide as substrate was 1.530 +/- 0.216 nmol h(-1) 10(-6) cells, using nicotinamide mononucleotide was 1.466 +/- 0.354 nmol h(-1) 10(-6) cells. The apparent K(M) values were 0.015 mM for the former substrate and 0.167 mM for the latter. The mean activity of nicotinic acid phosphoribosyltransferase was 0.038 +/- 0.014 nmol h(-1) 10(-6) cells, and the apparent K(M) for nicotinic acid was 0.165 mM. The proposed methods, easy and rapid to perform, are reliable and sensitive, avoiding the use of radiolabels except for NAPRT and displaying a very low activity. The reported findings, together with the previous ones in human erythrocytes, can provide an useful base to investigate NAD metabolism in humans through the study of blood cells.

Effect of ex vivo hyperthermia on radiation-induced micronuclei in lymphocytes of cancer patients before and during radiotherapy

To investigate the effect of ex vivo hyperthermia (HT) and 137Cs-irradiation on micronucleus (MN) production in cytokinesis-blocked lymphocytes, we obtained the peripheral blood samples from the same cancer patients (n=6) before and during fractionated partial-body radiotherapy (xRT). The whole blood cultures were heated at 43.5 degrees C for 60 min, followed by 137Cs irradiation (0-4 Gy). The control cultures from the same patients were incubated at 37 degreesC after being exposed to radiation. The lymphocytes were then stimulated with PHA. Cytochalasin B was applied at 44 h, and lymphocytes were harvested at 72 h. MN frequency was determined on Giemsa-stained slides. We found that in patients before xRT, HT (43.5 degrees C) significantly increased the MN yield (mean+/-SEM) in unirradiated lymphocytes from 15.6+/-2.8 (37 degrees C) to 39.7+/-10.9. Further, in patients either before or during xRT, when the lymphocytes were treated with HT (43.5 degrees C) and combined with ex vivo irradiation, the MN yield (Y) could be estimated by a linear equation Y=C+alphaD. Our findings indicate that as measured by the MN production in cytokinesis-blocked lymphocytes, HT alone at 43.5 degrees C++ induced DNA damage. Moreover, it enhanced the radiation-induced cytogenetic damage. Therefore, the application of HT may impair the T-cell function in cancer patients who are receiving radiotherapy. 1998 Elsevier Science B.V.

Whole-body hyperthermia and ADPRT inhibition in experimental treatment of brain tumors

Malignant primary brain tumors have hitherto been incurable. One reason for this may be the migrating tumor cells that spread into the surrounding normal brain, creating the basis for inevitable recurrences. Therefore, local therapy may have a temporary effect, but for a cure, the treatment must reach all the tumor cells. Whole-body hyperthermia (WBH) is such a general treatment, which we have studied in a rat glioma model. Cells of the RG2 rat glioma cell line were inoculated in the right caudate nucleus of Fischer-344 rats, which were then either controls or treated with WBH, induced by a radiant heat device for 4-5 sessions of 30 min at body temperature 42 degrees C (rectal), and/or nicotinamide (NAM), an effective radiosensitizer in animal tumor models and an inhibitor of ADPRT (poly adenosine diphosphate ribosyl transferase), a chromatin-bound enzyme suggested to be important in the DNA repair system. We have shown that WBH 42 degrees C alone, or in combination with NAM, has no effect upon tumor growth if a larger number of RG2 cells (5,000) are inoculated. If only 1,000 cells are inoculated, a significant inhibitory effect (p < 0.05) is observed on tumor growth as compared to the untreated control animals. Thus, WBH is feasible, and in some circumstances effective, in a rat glioma model. WBH in combination with other therapies influencing cell metabolism may be of value in future postoperative treatment of human malignant brain tumors.

Cytotoxic interactions of tumor necrosis factor, melphalan and 41.8 degrees C hyperthermia

Experience with limb perfusion-hyperthermia, TNF, and L-PAM suggests dramatic clinical responses in sarcoma and malignant melanoma. To extrapolate these results to clinical 41.8 degrees C whole-body hyperthermia (WBH) and systemic therapy, we studied the cytotoxic interactions of TNF, L-PAM and hyperthermia in L929 cells. The optimal sequence was TNF preceding 41.8 degrees C hyperthermia by 48 h, and L-PAM given simultaneously with heat. Trimodality synergism between TNF, hyperthermia and L-PAM was demonstrated. Non-cytotoxic doses of TNF had a super-additive interaction with L-PAM/heat. Conversely, non-cytotoxic doses of L-PAM had super-additive interactions with TNF followed by hyperthermia. Relative to therapeutic index, we studied WBH, L-PAM and TNF in non-tumor bearing mice. The optimal trimodality sequence did not result in increased normal tissue toxicity compared to L-PAM alone. The concentrations and sequencing of TNF and L-PAM studied are consistent with clinical application to WBH.