Melatonin Administered before or after a Cytotoxic Drug Increases Mammary Cancer Stabilization Rates in HER2/Neu Mice.

INTRODUCTION: The effects of chemotherapy are known to depend on the time of administration. Circadian rhythms are disturbed in tumors and in tumor bearers. Agents involved in controlling the circadian rhythms (chronobiotics) potentially can modify the outcomes of chemotherapeutics administered at different times of the day. Pineal hormone melatonin (MT) is a prototypic chronobiotic. OBJECTIVE: The aim of the study was to investigate if MT can affect efficacy or toxicity of chemotherapy drugs administered at the extreme time points of the working day of hospital personnel. METHODS: Cyclophosphamide, adriamycin, and 5-fluorouracil (CAF) and adriamycin and docetaxel (AT) cytotoxic drug combinations were administered on day 0 at 11:00 a.m. or at 5:00 p.m. (UTC+03:00) to 6-month-old female HER2/neu transgenic FVB/N mice bearing mammary adenocarcinomas. Some mice were additionally provided with MT in drinking water (20 mg/L) at night 1 week before or 3 weeks after treatment or during both periods. Tumor node sizes, body weight, and blood cell counts were determined right before treatment and on days 2, 7, 14, and 21. RESULTS: Significant decrease in the mean tumor node volume was found by days 14 and 21 upon all CAF and AT treatment schedules, except in animals treated with AT at 5:00 p.m. without supplementation with MT. In the latter case, mean tumor node volume on day 21 was the same as in the control. Supplementation of AT administered at 5:00 p.m. with MT improved the tumor response. CAF and AT regimens supplemented with MT also augmented the number of tumor nodes that did not increase by more than 20% by day 21 as compared to CAF or AT alone, respectively. This effect was significant in groups treated with AT at 5:00 p.m. and consistent upon other schedules. On day 7, leukopenia and anemia were registered in groups treated with CAF regimen; however, blood cell counts normalized by day 14. Both CAF and AT were associated with drop in the body weight registered on day 7. Supplementation with MT did not affect changes of the body weight and blood counts. CONCLUSIONS: MT supplementation to cytotoxic drugs can improve antitumor response, especially if it is blunted because of an inappropriate time of administration.

The Effect of Polyphenolic Composition BP-C3 on the Efficacy and Hematological Toxicity of Cyclophosphamide in the Chemotherapy of Mice Bearing Soft Tissue Sarcomas Induced by Benzo[a]pyrene.

This study aimed to evaluate the effect of lignin-derived polyphenolic composition BP-C3 on the efficacy and hematological toxicity of cyclophosphamide (CPA). Male and female Swiss-H derived mice bearing benzo[a]pyrene-induced soft tissue sarcomas were treated with CPA 300 mg/kg, BP-C3 75 mg/kg, or a combination. Tumor growth inhibition in male mice treated with CPA, BP-C3, or a combination of CPA and BP-C3 was significant and corresponded to 78%, 45%, and 82%, respectively, on day 21 after CPA administration on day 0. In female mice, tumor growth inhibition was 58%, -11%, and 35% when treated with CPA, BP-C3, or a combination of CPA and BP-C3, respectively. CPA administration resulted in significant hematological toxicity evidenced by a decreased white blood cell count on day 4 (2.43 ± 1.77 × 109/L in male mice and 1.19 ± 0.71 × 109/L in female mice) and anemia development on day 7 (6.55 ± 1.74 × 1012/L in male mice and 5.89 ± 2.24 × 1012/L in female mice). The red blood cell count measured on day 7 in animals treated with the combination of BP-C3 and CPA constituted 7.12 ± 1.17 × 1012/L and 7.36 ± 2.07 × 1012/L for male and female mice, respectively. The results of our study demonstrate the antitumor activity of BP-C3 in male mice bearing soft tissue sarcomas. Neither the antitumor activity nor the hematological toxicity of CPA were significantly influenced by BP-C3. A less pronounced effect of CPA on RBC count is demonstrated when this agent is given jointly with BP-C3.

Comparative efficacy evaluation of catheter intraperitoneal chemotherapy, normothermic and hyperthermic chemoperfusion in a rat model of ascitic ovarian cancer.

OBJECTIVES: The choice of an optimal administration route for intraperitoneal (IP) chemotherapy and a suitable chemotherapeutic regime in the treatment of ovarian cancer remains a controversy. We investigated survival outcomes according to catheter intraperitoneal chemotherapy (CIPC), normothermic and hyperthermic chemoperfusion (NIPEC and HIPEC) with cytostatic drugs dioxadet and cisplatin in rats with transplantable ascitic ovarian cancer. METHODS: Ascitic liquid containing 1 × 107 tumour cells was inoculated to female Wistar rats and 48 hours after rats received dioxadet and cisplatin at the maximum tolerated doses. Dioxadet at doses 1.5, 30 and 15 mg/kg and cisplatin at doses 4, 40 and 20 mg/kg body weight were administered for CIPC, NIPEC and HIPEC, respectively. Rats in the control groups received physiological saline and CIPC with physiological saline was regarded as the untreated control. The antitumor activity of the drugs was evaluated as an increase in average life expectancy (ALE). Analysis of the data was based primarily on Bayesian statistics and included Kaplan-Meier method, log-rank test and hazard ratio (HR) estimation. RESULTS: Compared to the untreated control CIPC, NIPEC and HIPEC with dioxadet significantly increased ALE by 101316, 61524 and 1.71735 days, whereas with cisplatin by 61013, 122437 and -13523 days, respectively. CONCLUSIONS: Dioxadet and cisplatin show similar efficacy in the CIPC route. Compared with CIPC IP chemotherapy by chemoperfusions is more effective for both the drugs. Dioxadet in HIPEC showed highest survival benefit whereas largest effect during NIPEC is achieved with cisplatin.

Both heat and new chemotherapeutic drug dioxadet in hyperthermic intraperitoneal chemoperfusion improved survival in rat ovarian cancer model.

BACKGROUND AND OBJECTIVES: Hyperthermic Intraperitoneal Chemotherapy (HIPEC) at the time of Cytoreductive Surgery (CRS) is an actively researched treatment in patients with advanced ovarian cancer. Relative contribution of heat and chemotherapeutic agents during HIPEC as well as efficacy of a new agent dioxadet for regional chemotherapy in a rat model of ovarian cancer was studied. METHODS: Sixty rats were divided into three groups: no treatment control group (n = 19), hyperthermia without chemotherapy (HIPEP) (n = 14), HIPEC + cisplatin (n = 14), HIPEC + dioxadet (n = 13). The intra-abdominal tumor was not resected. End points were: median survival (primary), cause of death (secondary). RESULTS: The median survival of the animals in the control group, HIPEP group, HIPEC + cisplatin, HIPEC + dioxadet were 9 (CI; 8-23), 22.5 (CI; 12-43), 25.5 (CI; 13-62), 49 (Cl; 28-70) days, respectively. The P-values control versus HIPEP, HIPEC + cisplatin versus HIPEC + dioxadet were 0.006, 0.002, and 0.001, respectively. CONCLUSION: During HIPEC both the heat and the cytotoxic drug had antitumor effects in a rat ovarian cancer model. Dioxadet showed potential as a drug for regional chemotherapy. J. Surg. Oncol. 2016;113:438-442. © 2015 Wiley Periodicals, Inc.