Melatonin and carcinogenesis in mice: the 50th anniversary of relationships.

The history of studies of melatonin effects on cancer in mice is outlined, the main lesson being that the systemic in vivo effects of melatonin on animals may overwhelm the in vitro effects found using tissue explants or cell cultures. In particular, the timing of melatonin administration is of crucial importance for using the drug, which is freely available over counter and thus needs no licensing for its applications in oncology.

Effects of Isoflavone-Rich NADES Extract of Pueraria lobata Roots and Astaxanthin-Rich Phaffia rhodozyma Extract on Prostate Carcinogenesis in Rats.

Prostate cancer (PCa) is one of the most common male malignancies worldwide. In the current study, we evaluated the effects of a natural deep eutectic solvent (NADES) extract of Pueraria lobata roots rich in isoflavones (ISF) and Phaffia rhodozyma extract rich in astaxanthin (ASX) on an N-methyl-N-nitrosourea plus testosterone PCa model in rats. ISF consisted of puerarin, daidzein, genistein, formononetin and other polyphenols, while ASX contained lipids and unsaturated species in addition to astaxanthin. Extracts were administered through a whole promotion period in daily doses shown by our group to successfully inhibit benign prostate hyperplasia (BPH) development - 200 mg/kg for ISF and 25 mg/kg for ASX. Though a similar effect was found for BPH processes accompanying PCa induction, the incidence of PCa in animals treated with placebo, ISF and ASX was 37%, 37% and 41%, respectively, showing no chemopreventive activity of ISF and ASX. PCa development was associated with a decrease in the Ca/Mg ratio in serum and an increase in prostate tissue. Treatment with both extracts produced a normalization effect on Ca balance in serum, which, combined with a decrease in the prostatic index, suggests some positive health effects of ISF and ASX.

Antigenotoxic and antimutagenic effects of lignin derivative BP-C2 against dioxidine and cyclophosphamide in vivo in murine cells.

The study investigated antigenotoxic and antimutagenic activity of novel lignin-derived polyphenolic composition (BP-C2) with ammonium molybdate towards cyclophosphamide and dioxidine in the bone marrow, blood and liver cells of BALB/c mice. BP-C2 was given to mice via gavage at 60, 80 and 120 mg/kg once 1 h before single intraperitoneal injection of a genotoxic agent. 1.5 h and 3 h after dioxidine or cyclophosphamide injection, respectively, cellular suspensions were obtained from mice and assessed with the comet test and cytogenetic analysis of bone marrow cells. It was observed that antigenotoxic activity of BP-C2 against DNA damage induced by dioxidine, a prooxidant genotoxic agent, in the bone marrow, liver and blood cells of mice in vivo was more pronounced at 60 and 80 mg/kg than at 120 mg/kg. When cyclophosphamide was used to induce a DNA damage, the genoprotective effect of BP-C2 was observed in bone marrow, liver and blood cells at 60 mg/kg dose but the effect was not significant at 80 mg/kg. When co-administered with 120 mg/kg BP-C2, cyclophosphamide induced a higher level of DNA damage in liver cells, but its genotoxic effect in bone marrow and blood cells was the same as when it was administered alone. When assessing the effect of BP-C2 on chromosomal aberrations induced by cyclophosphamide and dioxidine in bone marrow cells, it was revealed that all three tested doses of BP-C2 significantly decreased the number of cells with chromosome abnormalities. Thus, BP-C2 has a pronounced antimutagenic and genoprotective effects.

Assessment of antitumor activity of BP-C1, a platinum-based anticancer agent with a lignin-derived polymeric ligand, in autochthonous induced and spontaneous carcinogenesis rodent models.

BACKGROUND: A standard approach to study the anticancer activity of novel drugs is their testing in animals with inoculated tumors, which has some limitations. An alternative is the use of spontaneous or carcinogen-induced tumor models as they have better translation potential. The carcinogen-induced and transgenic tumor models were used to assess the antitumor activity of BP-C1, a platinum-containing drug with lignin-derived polymeric ligand. METHODS: We used female Swiss-H-derived mice and Wistar female rats to induce autochthonous tumors via exposure to benzo[a]pyrene and 1,2-dimethylhydrazine, respectively. Additionally, transgenic HER-2/neu FVB/N female mice, prone to the development of spontaneous mammary carcinomas, were used. RESULTS: Antitumor activity of BP-C1 was observed in soft tissue sarcomas, induced by benzo[a]pyrene. The animals treated with BP-C1 exhibited more stabilizations and therapy responses compared to placebo controls. The efficacy of BP-C1 was somewhat reduced compared to cyclophosphamide; however, their combination resulted in an enhanced antitumor effect. For the 1,2-dimethylhydrazine-induced rat colon cancer model, BP-C1 reduced tumor multiplicity by 21-41 %. For mammary adenocarcinomas in HER-2/neu FVB/N mice, short-termed complete responses were observed in the BP-C1 groups with a frequency of 12-13 %, while complete responses were absent in the placebo group. CONCLUSION: The results acquired indicated a wide spectrum of antitumor activity of BP-C1.

The presence of polymorphisms in genes controlling neurotransmitter metabolism and disease prognosis in patients with prostate cancer: a possible link with schizophrenia.

Polymorphisms of neurotransmitter metabolism genes were studied in patients with prostate cancer (PC) characterized by either reduced or extended serum prostate-specific antigen doubling time (PSADT) corresponding to unfavorable and favorable disease prognosis respectively. The 'unfavorable prognosis' group (40 cases) was defined by PSADT ≤ 2 months, whereas patients in the 'favorable prognosis' group (67 cases) had PSADT ≥ 30 months. The following gene polymorphisms known to be associated with neuropsychiatric disorders were investigated: a) the STin2 VNTR in the serotonin transporter SLC6A4 gene; b) the 30-bp VNTR in the monoamine oxidase A MAOA gene; c) the Val158Met polymorphism in the catechol-ortho-methyltransferase COMT gene; d) the promoter region C-521T polymorphism and the 48 VNTR in the third exon of the dopamine receptor DRD4 gene. The STin2 12R/10R variant of the SLC6A4 gene (OR = 2.278; 95% CI = 0.953-5.444) and the -521T/T homozygosity of the DRD4 gene (OR = 1.579; 95% CI = 0.663-3.761) tended to be overrepresented in PC patients with unfavorable disease prognosis. These gene variants are regarded as protective against schizophrenia, and the observed trend may be directly related to a reduced PC risk described for schizophrenia patients. These results warrant further investigation of the potential role of neurotransmitter metabolism gene polymorphisms in PC pathogenesis.

Melatonin increases overall survival of prostate cancer patients with poor prognosis after combined hormone radiation treatment.

BACKGROUND: The antitumor and immunomodulating activities of melatonin are widely known. These activities are based upon the multifactorial mechanism of action on various links of carcinogenesis. In the present paper, the long-term results of the clinical use of melatonin in the combined treatment of patients with prostate cancer of various risk groups were evaluated. MATERIALS AND METHODS: A retrospective study included 955 patients of various stages of prostate cancer (PCa) who received combined hormone radiation treatment from 2000 to 2019. Comprehensive statistical methods were used to analyze the overall survival rate of PCa patients treated with melatonin in various prognosis groups. RESULTS: The overall survival rate of PCa patients with favorable and intermediate prognoses treated or not treated with melatonin was not statistically significantly different. In the poor prognosis group, the median overall survival in patients taking the drug was 153.5 months versus 64.0 months in patients not using it (p < 0.0001). The 5-year overall survival rates in the research and control groups were 66.8 ± 1.9 and 53.7 ± 2.6 (p < 0.0001) respectively. In a multivariate analysis, melatonin administration proved to be an independent prognostic factor and reduced the risk of death of PCa patients by more than twice (p < 0.0001). CONCLUSIONS: The multicomponent antitumor effect of melatonin is fully realized and clearly demonstrated in treatment of PCa patients with poor prognosis with a set of unfavorable factors of the tumor progression.

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.

Aging and cancer: Is glucose a mediator between them?

Aging can increase cancer incidence because of accumulated mutations that initiate cancer and via compromised body control of premalignant lesions development into cancer. Relative contributions of these two factors are debated. Recent evidence suggests that the latter is rate limiting. In particular, hyperglycemia caused by compromised body control of blood glucose may be a factor of selection of somatic mutation-bearing cells for the ability to use glucose for proliferation. High glucose utilization in aerobic glycolysis is a long known characteristic of cancer. The new evidence adds to the concepts that have been being developed starting from mid-1970ies to suggest that age-related shifts in glucose and lipid metabolism increase the risk of cancer and compromise prognoses for cancer patients and to propose antidiabetic biguanides, including metformin, for cancer prevention and as an adjuvant means of cancer treatment aimed at the metabolic rehabilitation of patients. The new evidence is consistent with several effects of glucose contributing to aging and acting synergistically to enhance carcinogenesis. Glucose can affect (i) separate cells (via promoting somatic mutagenesis and epigenetic instability), (ii) cell populations (via being a factor of selection of phenotypic variants in cell populations for higher glucose consumption and, ultimately, for high aerobic glycolysis); (iii) cell microenvironment (via modification of extracellular matrix proteins), and (iv) the systemic levels (via shifting the endocrine regulation of metabolism toward increasing blood lipids and body fat, which compromise immunological surveillance and promote inflammation). Thus, maintenance of youthful metabolic characteristics must be important for cancer prevention and treatment.

Prognostic value of tumor growth kinetic parameters in prostate cancer patients.

The goal of this paper was to estimate the predictive value of kinetic parameters of tumor growth in 109 prostatic cancer (PCa) patients with the morphologically verified diagnosis. Results: The cell loss factor, calculated on the basis of Ki-67 values, and the PSA doubling time, proved to be an important prognostic parameter. A cumulative comparative analysis of these criteria, depending on the prevalence of the tumor process, indicates that the level of cell loss significantly decreases with increasing tumor stage (p = 1*10-5), and the growth rate of the tumor significantly increases (p = 1*10-6). In the multivariate prognostic model, the CLF is an independent predictor of tumor-specific survival along with the stage of PCa. Materials and methods: For each patient of the study group were as follows. The level of Ki-67 expression in biopsies of adenocarcinoma of the prostate gland was estimated. Also, in the selected group of patients, based on the available data on the kinetics of the prostatic specific antigen (PSA), the initial time of doubling of PSA was determined. The obtained values of the actual tumor growth rate and the cell loss factor (CLF) were compared with the parameters characterizing the tumor state (stage, Gleason score, PSA level at diagnosis) and tumor-specific survival rates. Conclusion: Inclusion of proliferative activity factors in nomograms and prognostic models will increase their prognostic value and practical significance. Further prospective studies are needed to analyze the actual growth rate of PCa and evaluate its proliferative activity.

In mice transgenic for IGF1 under keratin-14 promoter, lifespan is decreased and the rates of aging and thymus involution are accelerated.

IGF1 signaling is supposedly a key lifespan determinant in metazoans. However, controversial lifespan data were obtained with different means used to modify IGF1 or its receptor (IGF1R) expression in mice. The emerging puzzle lacks pieces of evidence needed to construct a coherent picture. We add to the available evidence by using the Gompertz model (GM), with account for the artifactual component of the Strehler-Mildvan correlation between its parameters, to compare the survival patterns of female FVB/N and FVB/N-derived K14/mIGF1 mice. In K14/mIGF1 vs. FVB/N mice, the rate of aging (γ) is markedly increased without concomitant changes in the initial mortality (µ0). In published cases where IGF1 signaling was altered by modifying liver or muscle IGF1 or whole body IGF1R expression, lifespan changes are attributable to µ0. The accelerated aging and associated tumor yield in K14/mIGF1 mice are consistent with the finding that the age-associated decreases in thymus weight and serum thymulin are accelerated in K14/mIGF1 mice. Our results underscore the importance of accounting for the mathematical artifacts of data fitting to GM in attempts to resolve discrepancies in survival data and to differentiate the contributions of the initial mortality and the rate of aging to changes in lifespan.

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.

It is necessary to establish an International Agency for Research on Aging.

The global aging of human population is one of the main challenges and opportunities of the 21st century. Establishing an International Agency for Research on Aging as an entity affiliated to one of the intergovernmental institutions, such as the World Health Organization, can be crucial for promoting international collaboration in gerontology, in particular in a search of effective and safe geroprotectors for humans.

Novel water-soluble lignin derivative BP-Cx-1: identification of components and screening of potential targets in silico and in vitro.

Identification of molecular targets and mechanism of action is always a challenge, in particular - for natural compounds due to inherent chemical complexity. BP-Cx-1 is a water-soluble modification of hydrolyzed lignin used as the platform for a portfolio of innovative pharmacological products aimed for therapy and supportive care of oncological patients. The present study describes a new approach, which combines in vitro screening of potential molecular targets for BP-Cx-1 using Diversity Profile - P9 panel by Eurofins Cerep (France) with a search of possible active components in silico in ChEMBL - manually curated chemical database of bioactive molecules with drug-like properties. The results of diversity assay demonstrate that BP-Cx-1 has multiple biological effects on neurotransmitters receptors, ligand-gated ion channels and transporters. Of particular importance is that the major part of identified molecular targets are involved in modulation of inflammation and immune response and might be related to tumorigenesis. Characterization of molecular composition of BP-Cx-1 with Fourier Transform Ion Cyclotron Resonance Mass Spectrometry and subsequent identification of possible active components by searching for molecular matches in silico in ChEMBL indicated polyphenolic components, nominally, flavonoids, sapogenins, phenanthrenes, as the major carriers of biological activity of BP-Cx-1. In vitro and in silico target screening yielded overlapping lists of proteins: adenosine receptors, dopamine receptor DRD4, glucocorticoid receptor, serotonin receptor 5-HT1, prostaglandin receptors, muscarinic cholinergic receptor, GABAA receptor. The pleiotropic molecular activities of polyphenolic components are beneficial in treatment of multifactorial disorders such as diseases associated with chronic inflammation and cancer.

Effect of the polyphenol composition BP-C3 on haematological and intestinal indicators of 5-fluorouracil toxicity in mice.

BP-C3 is a formulation, which comprises lignin-derived polyphenolic composition of benzenepolycarboxylic acids (BP-Cx-1) with iron complex, selenium, ascorbic acid and retinol, and possesses geroprotective activity. The present study examined the effect of BP-C3 (80 mg/kg, administered 18 times in total by gavage) on the development of haematological and intestinal manifestations of toxicity following 5-fluorouracil (5-FU; 150 mg/kg, administered once via intravenous injection) administration in outbred male Swiss-H Rappolovo (SHR) mice. The use of BP-C3 on therapeutic and preventative/therapeutic schedules demonstrated that it was protective against the toxic effect of 5-FU exerted on the lymphopoietic organs. Administering ВР-С3 24 h after 5-FU (therapeutic schedule) had an effect on the recovery of leukopoiesis and prevented anaemia in the mice. In the mice that received 5-FU and 5-FU with BP-C3 prior to and following administration of the chemotherapeutic agent (preventative/therapeutic schedule), mild anaemia developed by day 7. Administration of BP-C3 without 5-FU did not affect blood cell differentiation in the mice. Thus, BP-C3, depending on the administration schedule, had different effects on the haematological parameters of haematopoietic organs and peripheral blood in mice exposed to 5-FU. BP-C3 promoted intestinal crypt survival when administered on the preventative/therapeutic and therapeutic schedules, suggesting that the formulation protects the epithelium of the small intestine against damage by 5-FU.

Radioprotective and radiomitigative effects of BP-C2, a novel lignin-derived polyphenolic composition with ammonium molybdate, in two mouse strains exposed to total body irradiation.

PURPOSE: There remains an unmet medical need for radioprotective and mitigative agents. BP-C2 is a novel lignin-derived polyphenolic composition with ammonium molybdate, developed as radioprotector/radiomitigator. OBJECTIVES: The present study evaluated BP-C2 for the mitigation of acute radiation syndrome (ARS). METHODS: A total-body irradiation mouse model (TBI, 4.0-8.0 Gy) was used in the study. RESULTS: In a 30-day survival study, performed in CBA mice, BP-C2, at a dosage of 81.0 mg/kg, improved survival (dose reduction factor (DRF) = 1.1) and increased the formation of endogenous spleen colony-forming units (CFU). In C57BL/6 mice, BP-C2, when administered daily for 7 days, starting 24 hours after TBI, also improved survival. In animals irradiated with 5.0 Gy, BP-C2 increased the number of CFUs (6.7 ± 5.1) compared to the 5.0 Gy placebo group (2.3 ± 2.3, p = .0245). The number of surviving intestinal crypts was maintained in the 5.0 Gy BP-C2 group (133.7 ± 13.9), in contrast to the 5.0 Gy placebo group (124.2 ± 10.5, p < .0023). BP-C2 also increased the number of LGR5 + positive cells in intestinal crypts. CONCLUSION: BP-C2 mitigates radiation-induced damage in mid-lethal range of radiation doses. Effects are mediated by enhancement of extramedullar hematopoiesis in the spleen and a protective effect on the intestinal epithelium.

Pretreatment prostate specific antigen doubling time as prognostic factor in prostate cancer patients.

Despite the prostate-specific antigen (PSA) serum level commonly uses as tumor marker in diagnosis of prostate cancer, it seems that PSA doubling time (PSADT) could be more useful indicator of tumor behavior and of prognosis for patients. The results of hormone and radiation therapy were evaluated for 912 prostate cancer having at least 2 PSA tests before the treatment was started. Clustering procedure (selection of homogenous group) was performed by using PSADT as the classification marker. The rate of PSADT was estimated for different dissemination rate, age, Gleasons's score and education level. PSADT index inversely correlated with the rate of prostate cancer dissemination, Gleason's score and the level of education were directly correlated with the age of patients. Survival time was longer and PSADT index was higher in "slow" tumor growing subgroups in local, local-advanced and metastatic prostate cancer patients than these in "fast" subgroups. The study confirmed the prognostic value of pretreatment PSADT in prostate cancer patients independently of cancer progression. No significant relationship exists between the authors and the companies/organizations whose products or services may be referenced in this article.

Metformin prevents hormonal and metabolic disturbances and 1,2-dimethylhydrazine-induced colon carcinogenesis in non-diabetic rats.

Effects of two doses of the anti-diabetic drug, metformin (MF), on hormonal and metabolic levels of serum of non-diabetic male Wistar rats with 1,2-dimethylhydrazine (DMH)-induced colon tumor adenocarcinomas were studied. Carcinogenesis in the animals was also observed. Rats with DMH-induced colon adenocarcinomas had elevated levels of serum glucose, insulin, insulin-like growth factor-1, total cholesterol, triglycerides, catalase, malonic dialdehyde, glycated hemoglobin, aspartate aminotransferase, and alanine aminotransferase and decreased hemoglobin. Treatment with two doses of MF normalized majority of these changes in DMH-treated rats, whereas the drug was ineffective in rats without DMH treatment. The only exception was the decreased triglyceride levels in MF-treated rats. A 100 mg/kg dose of MF increased DMH-induced exophytic colon carcinomas and decreased endophytic tumors compared with untreated rats. Moreover, both MF doses increased DMH-induced and highly differentiated tumors and decreased the invasiveness of colon carcinomas compared with rats provided with DMH and water. Therefore, effects of MF on metabolic homeostasis are critical for preventing colon cancer.