Design and synthesis of coumarin-based organoselenium as a new hit for myeloprotection and synergistic therapeutic efficacy in adjuvant therapy.

A newly designed organoselenium compound, methyl substituted umbelliferone selenocyanate (MUS), was synthesized as a primary hit against the myelotoxic activity of carboplatin. MUS was administered at 6 mg/kg b.wt, p.o. in concomitant and pretreatment schedules with carboplatin (12 mg/kg b.wt, i.p. for 10 days) in female Swiss albino mouse. MUS treatment reduced (P < 0.001) the percentage of chromosomal aberrations, micronuclei formation, DNA damage and apoptosis in murine bone marrow cells and also enhanced (P < 0.001) the bone marrow cell proliferation of the carboplatin-treated mice. These activities cumulatively restored the viable bone marrow cell count towards normalcy. Myeloprotection by MUS was achieved, in part, due to a significant reduction in the ROS/RNS formation and restoration of glutathione redox pool. Additionally, MUS synergistically enhanced the cytotoxicity of carboplatin against two human cancer cell lines (MCF-7 and Colo-205). Furthermore, MUS can effectively potentiate the antitumour activity of carboplatin against two murine cancers (Dalton's Lymphoma and Sarcoma-180) in vivo. These preclinical findings clearly indicate that MUS can improve the therapeutic index of carboplatin and ensures more effective therapeutic strategy against cancer for clinical development.

Attenuation of doxorubicin-induced cardiotoxicity and genotoxicity by an indole-based natural compound 3,3'-diindolylmethane (DIM) through activation of Nrf2/ARE signaling pathways and inhibiting apoptosis.

The most crucial complication related to doxorubicin (DOX) therapy is nonspecific cytotoxic effect on healthy normal cells. The clinical use of this broad-spectrum chemotherapeutic agent is restricted due to development of severe form of cardiotoxicity, myelosuppression, and genotoxicity which interfere with therapeutic schedule, compromise treatment outcome and may lead to secondary malignancy. 3,3'-diindolylmethane (DIM) is a naturally occurring plant alkaloid formed by the hydrolysis of indolylmethyl glucosinolate (glucobrassicin). Therefore, the present study was undertaken to investigate the protective role of DIM against DOX-induced toxicity in mice. DOX was administered (5 mg/kg b.w., i.p.) and DIM was administered (25 mg/kg b.w., p.o.) in concomitant and 15 days pretreatment schedule. Results showed that DIM significantly attenuated DOX-induced oxidative stress in the cardiac tissues by reducing the levels of free radicals and lipid peroxidation, and by enhancing the level of glutathione (reduced) and the activity of antioxidant enzymes. The chemoprotective potential of DIM was confirmed by histopathological evaluation of heart and bone marrow niche. Moreover, DIM considerably mitigated DOX-induced clastogenicity, DNA damage, apoptosis, and myeloid hyperplasia in bone marrow niche. In addition, oral administration of DIM significantly (p < .05) stimulated the Nrf2-mediated activation of antioxidant response element (ARE) pathway and promoted expression of ARE-driven cytoprotective proteins, HO-1, NQO1, and glutathione-S-transferase (GST). In connection with that, DIM significantly attenuated DOX-induced apoptosis by upregulation of Bcl-2 expression and downregulation of Bax and caspase-3 expression. Thus, this study suggests that DIM has promising chemoprotective efficacy against DOX-induced toxicity and indicates its future use as an adjuvant in chemotherapy.

Sensitizing effects of an organovanadium compound during adjuvant therapy with cyclophosphamide in a murine tumor model.

Various epidemiological and preclinical studies have already established the cancer chemopreventive potential of vanadium. In addition, recent studies have also indicated the abilities of vanadium-based compounds to induce cell death selectively towards malignant cells. Therefore, the objective of the present investigation is to improve the therapeutic efficacy and toxicity profile of an alkylating agent, cyclophosphamide, by the concurrent use of an organovanadium compound, oxovanadium(IV)-l-cysteine methyl ester complex (VC-IV). In this study, VC-IV (1mg/kg b.w., p.o.) was administered alone as well as in combination with cyclophosphamide (25mg/kg b.w., i.p.) in concomitant and pretreatment schedules. The results showed that VC-IV in combination with cyclophosphamide resulted in an improved therapeutic efficacy as evidenced by reduction of tumor growth and prolongation of life span. The observed potentiation was mediated through generation of ROS in tumor cells, which ultimately led to significant DNA damage, and apoptosis in tumor cells. Further studies revealed that VC-IV sensitized tumor cells to cyclophosphamide therapy by down-regulating the anti-apoptotic protein Bcl-2 and by up-regulating molecules like p53, Bax, cytochrome c, caspases, which led to PARP cleavage and apoptosis. Significant inhibition of angiogenesis along with reduction in the levels of VEGF-A and MMP-9 in the tumor bed by VC-IV further contributed to the sensitization accomplished by VC-IV. Moreover, VC-IV ameliorated cyclophosphamide-induced hematopoietic, hepatic and genetic damages by modulating the antioxidant status in normal organs. Thus, the present study clearly demonstrated the sensitizing and protective efficacy of VC-IV and indicates it may serve as a promising adjuvant in cancer chemotherapy.

Chemoprotective and chemosensitizing properties of selenium nanoparticle (Nano-Se) during adjuvant therapy with cyclophosphamide in tumor-bearing mice.

Cyclophosphamide (CP) is one of the widely used anticancer agents; however, it has serious deleterious effects on normal host cells due to its nonspecific action. The essential trace element Selenium (Se) is suggested to have chemopreventive and chemotherapeutic efficacy and currently used in pharmaceutical formulations. Previous report had shown Nano-Se could protect CP-induced hepatotoxicity and genotoxicity in normal Swiss albino mice; however, its role in cancer management is still not clear. The aim of present study is to investigate the chemoprotective efficacy of Nano-Se against CP-induced toxicity as well as its chemoenhancing capability when used along with CP in Swiss albino mice against Ehrlich's ascites carcinoma (EAC) cells. CP was administered (25 mg/kg b.w., i.p.) and Nano-Se was given (2 mg Se/kg b.w., p.o.) in concomitant and pretreatment schedule. Increase levels of serum hepatic marker, hepatic lipid peroxidation, DNA damage, and chromosomal aberration in CP-treated mice were significantly (P < 0.05) reversed by Nano-Se. The lowered status of various antioxidant enzymes in tumor-bearing mice after CP treatment was also effectively increased by Nano-Se. Administration of Nano-Se along with CP caused a significant reduction in tumor volume, packed cell volume, viable tumor cell count, and increased the survivability of the tumor-bearing hosts. The results suggest that Nano-Se exhibits significant antitumor and antioxidant effects in EAC-bearing mice. The potential for Nano-Se to ameliorate the CP-evoked toxicity as well as to improve the chemotherapeutic effect could have beneficial implications for patients undergoing chemotherapy with CP.

Nano-Se attenuates cyclophosphamide-induced pulmonary injury through modulation of oxidative stress and DNA damage in Swiss albino mice.

Chemotherapy is an integral part of modern day treatment regimen but anticancer drugs fail to demarcate between cancerous and normal cells thereby causing severe form of systemic toxicity. Among which pulmonary toxicity is a dreadful complication developed in cancer patients upon cyclophosphamide (CP) therapy. Oxidative stress, fibrosis, and apoptosis are the major patho-mechanisms involved in CP-induced pulmonary toxicity. In the present study, we have synthesized Nano-Se, nanotechnology-based new form of elemental selenium which has significantly lower toxicity and acceptable bioavailability. In order to meet the need of effective drugs against CP-induced adverse effects, nano selenium (Nano-Se) was tested for its possible protective efficacy on CP-induced pulmonary toxicity and bone marrow toxicity. CP intoxication resulted in structural and functional lung impairment which was revealed by massive histopathological changes. Lung injury was associated with oxidative stress/lipid peroxidation as evident by increased in reactive oxygen species, nitric oxide level, and malondialdehyde (MDA) formation with decreased in level of antioxidants such as reduced glutathione, glutathione-S-transferase, glutathione peroxidase, superoxide dismutase, and catalase. Furthermore, CP at a dose of 25 mg/kg b.w. increased pulmonary DNA damage ('comet tail') and triggered DNA fragmentation and apoptosis in mouse bone marrow cells. On the other hand, Nano-Se at a dose of 2 mg Se/kg b.w., significantly inhibited CP-induced DNA damage in bronchoalveolar lavage cells, and decreased the apoptosis and percentage of DNA fragmentation in bone marrow cells and also antagonized the reduction of the activities of antioxidant enzymes and the increase level of MDA. Thus, our results suggest that Nano-Se in pre- and co-administration may serve as a promising preventive strategy against CP-induced pulmonary toxicity.

Molecular mechanism behind the synergistic activity of diphenylmethyl selenocyanate and Cisplatin against murine tumor model.

Various preclinical, clinical and epidemiological studies have already well established the cancer chemopreventive and chemoprotective potential of selenium compounds. In addition to its protective efficacy, recent studies have also proved the abilities of selenium compounds to induce cell death specifically in malignant cells. Therefore, our intention is to improve the therapeutic efficacy of an alkylating agent, cisplatin, by the adjuvant use of an organoselenium compound, diphenylmethyl selenocyanate (DMSE). It was observed that combined treatment decreased the tumor burden significantly through reactive oxygen species generation and modulation of antioxidant and detoxifying enzyme system in tumor cells. These activities ultimately led to significant DNA damage and apoptosis in tumor cells. Study of the molecular pathway disclosed that the adjuvant treatment caused induction of p53, Bax and suppressed Bcl-2 followed by the activation of caspase cascade. Furthermore, a concomitant decrease in cisplatin-induced nephrotoxicity and hematopoietic toxicity by DMSE might also have enhanced the efficacy of cisplatin and provided survival advantage to the host. Results suggested that the combination treatment with DMSE and cisplatin may offer potential therapeutic benefit, and utilization of cisplatin in cancer chemotherapy exempt of its limitations.

Intervention in cyclophosphamide induced oxidative stress and DNA damage by a flavonyl-thiazolidinedione based organoselenocyanate and evaluation of its efficacy during adjuvant therapy in tumor bearing mice.

A novel flavonyl-thiazolidinedione based organoselenocyanate compound was synthesized and established as nontoxic at the doses of 2.5 and 5 mg/kg b.w. in mice. Oral administration of the compound in combination with cyclophosphamide (CP) resulted in an improved therapeutic efficacy which was mostly evidenced in terms of tumor burden and protection of normal cells. The adjuvant therapy was proved to be immensely significant in increasing the mean survivability of the tumor bearing hosts. Reduction in the tumor volume was manifested through the induction of apoptosis and generation of ROS in transformed cells. Moreover, the organoselenium compound could efficiently suppress CP-induced DNA damage, chromosomal aberration, hepatic damage and enhanced the activities of various antioxidant enzymes in normal cells.

Antioxidative effects of the spice cardamom against non-melanoma skin cancer by modulating nuclear factor erythroid-2-related factor 2 and NF-κB signalling pathways.

The role of dietary factors in inhibiting or delaying the development of non-melanoma skin cancer (NMSC) has been investigated for many years. Cardamom, which is a dietary phytoproduct, has been commonly used in cuisines for flavour and has numerous health benefits, such as improving digestion and stimulating metabolism and having antitumorigenic effects. We have investigated the efficacy of dietary cardamom against 7,12-dimethylbenz[a]anthracene (DMBA)-induced skin papillomatogenesis in Swiss albino mice that closely resembles human NMSC. Mice were grouped into normal wild type (untreated), vehicle-treated (acetone), carcinogen-treated (DMBA), and DMBA and cardamom-treated (DMBA+CARD) to delineate the role of cardamom against DMBA-induced papillomatogenesis. Oral administration of cardamom to DMBA-treated mice up-regulated the phase II detoxification enzymes, such as glutathione-S-transferase and glutathione peroxidase, probably via activation of nuclear factor erythroid-2-related factor 2 transcription factor in 'DMBA+CARD' mice. Furthermore, reduced glutathione, glutathione reductase, superoxide dismutase and catalase were also up-regulated by cardamom in the same 'DMBA+CARD' group of mice compared with DMBA-treated mice. Cardamom ingestion in DMBA-treated mice blocked NF-κB activation and down-regulated cyclo-oxygenase-2 expression. As a consequence, both the size and the number of skin papillomas generated on the skin due to the DMBA treatment were reduced in the 'DMBA+CARD' group. Thus, the results from the present study suggest that cardamom has a potential to become a pivotal chemopreventive agent to prevent papillomagenesis on the skin.

Psorinum therapy in treating stomach, gall bladder, pancreatic, and liver cancers: a prospective clinical study.

We prospectively studied the clinical efficacy of an alternative cancer treatment "Psorinum Therapy" in treating stomach, gall bladder, pancreatic and liver cancers. Our study was observational, open level and single arm. The participants' eligibility criteria included histopathology/cytopathology confirmation of malignancy, inoperable tumor, and no prior chemotherapy or radiation therapy. The primary outcome measures of the study were (i) to assess the radiological tumor response (ii) to find out how many participants survived at least 1 year, 2 years, 3 years, 4 years and finally 5 years after the beginning of the study considering each type of cancer. Psorinum-6x was administered orally to all the participants up to 0.02 ml/Kg body weight as a single dose in empty stomach per day for 2 years along with allopathic and homeopathic supportive cares. 158 participants (42 of stomach, 40 of gall bladder, 44 of pancreatic, 32 of liver) were included in the final analysis of the study. Complete tumor response occurred in 28 (17.72%) cases and partial tumor response occurred in 56 (35.44%) cases. Double-blind randomized controlled clinical trial should be conducted for further scientific exploration of this alternative cancer treatment.

Naphthalimide based novel organoselenocyanates: finding less toxic forms of selenium that would retain protective efficacy.

A series of naphthalimide based organoselenocyanates were synthesized and screened for their toxicity as well as their ability to modulate several detoxifying/antioxidative enzyme levels at a primary screening dose of 3 mg/kg b.w. in normal Swiss albino mice for 30 days. Compound 4d showed highest activity in elevating the detoxifying/antioxidant enzymes levels.

Diphenylmethyl selenocyanate inhibits DMBA-croton oil induced two-stage mouse skin carcinogenesis by inducing apoptosis and inhibiting cutaneous cell proliferation.

Numerous epidemiological and experimental studies have showed the inverse relationship between dietary selenium intake and different types of cancer. Continuous efforts are going on to develop suitable organoselenium compounds, which can be used as cancer chemopreventive agents for human. In the present study, a synthetic organoselenium compound diphenylmethyl selenocyanate was evaluated for its ability to arrest cell proliferation and to induce apoptosis against 7,12-dimethylbenz[a]anthracene-croton oil induced two-stage mouse skin carcinogenesis model. Reduction in the incidence and number of papilloma, the preneoplastic lesion, was considered to be the mean of assessment. Significant decrease in the level of cell proliferation (p<0.01) and significant enhancement in the level of apoptosis (p<0.01) were found. Caspase-3, which contribute a part in the process of cellular apoptosis to prevent further cellular differentiation was also elevated significantly (P<0.01) during the treatment with the Se compound. These observations seem to be correlated with the significant reduction in the corresponding number of skin papilloma formation after 12 weeks of experiment. Thus the compound, diphenylmethyl selenocyanate may be considered for further research to establish it as an effective cancer chemopreventive agent.

Anti-tumour promoting activity of diphenylmethyl selenocyanate against two-stage mouse skin carcinogenesis.

Epidemiological, clinical and experimental evidence collectively suggests that Se in different inorganic and organic forms provides a potential cancer chemopreventive agent, active against several types of cancer. It can exert preventive activity in all the three stages of cancer: initiation, promotion and progression. Literature reports revealed that organoselenocyanates have more potential as chemopreventive agents than inorganic forms due to their lower toxicity. In our previous report we showed chemopreventive efficacy of diphenylmethyl selenocyanate during the initiation and pre- plus post-initiation phases of skin and colon carcinogenesis process. The present study was undertaken to explore the anti-tumour promoting activity of diphenylmethyl selenocyanate in a 7,12-dimethylbenz (a) anthracene (DMBA)-croton oil two-stage skin carcinogenesis model. The results obtained showed significant (p<0.01) reduction of the incidence and number of skin papillomas, precancerous skin lesions, along with significant (p<0.01) elevation of phase II detoxifying enzymes (GST, Catalase and SOD) and inhibition of lipid peroxidation in liver and skin. Thus, the present data strongly suggest that diphenylmethyl selenocyanate also has the potential to act as anti-tumour promoter agent in a two-stage skin carcinogenesis mouse model, pointing to possible general efficacy.

Inhibition of azoxymethane-induced aberrant crypt foci in rat by diphenylmethyl selenocyanate through downregulation of COX-2 and modulation of glutathione-S-transferase and lipid peroxidation.

Preventive intervention of colorectal cancer has become essential, as a major portion of the population could develop the disease at some point during their lives. An inverse association between dietary intake of selenium, an important biological trace element, and colorectal cancer risk has been observed through epidemiological and experimental studies. Inhibitory activity of an organoselenocyanate, diphenylmethylselenocyanate, was tested on azoxymethane (15 mg/kg body wt) induced colon carcinogenesis in Sprague-Dawley rats. Pretreatment and concomitant treatment, at a dose of 2 mg/kg body wt, was carried out and the effect was observed on aberrant crypt foci, the preneoplastic lesion. To investigate the mechanism of action of the compound, lipid peroxidation level and glutathione-S-transferase (GST) activities were assessed in the liver as well as in the colon. Expression of cyclooxygenase-2 protein, inducible during colon carcinogenesis, was also analyzed in the colon. Inhibitory activity of the compound was shown by the reduced incidences of aberrant crypt foci in the treated groups (by 63.3%, p=0.00044 in the pretreated group, and by 44%, p=0.0067 in the concomitant treatment group). Significant induction of GST activities and significant reduction in lipid peroxidation level both in the liver as well as in the colon and suppression of cyclooxygenase-2 expression in the colon of the treated groups suggest that the compound could exert its preventive effect at different levels of the carcinogenic process. The preventive effect was better in the pretreatment group than in the concomitant treatment group, suggesting some added protection to the target tissue resulting from preadministration of the compound.

Inhibition of DMBA-croton oil two-stage mouse skin carcinogenesis by diphenylmethyl selenocyanate through modulation of cutaneous oxidative stress and inhibition of nitric oxide production.

Selenium, an essential micronutrient, plays important roles against different diseases, including several types of cancer. In the present study, antioxidative and chemopreventive properties of a synthetic organoselenium compound, diphenylmethyl selenocyanate, were evaluated with a 7,12-dimethylbenz (a) anthracene - croton oil induced two-stage mouse skin carcinogenesis model. The compound was administered orally to carcinogen-treated mice at two different non-toxic doses, 2mg/kg. b.w. and 3mg/kg. b.w. Significant inhibition in the incidence of papilloma formation (53-80%) as well as in the cumulative numbers of papillomas per papilloma bearing mouse were observed in the treated groups as compared to the carcinogen control group. The compound was also found to upregulate significantly different phase II detoxifying enzymes such as glutathione-S-transferase (p<0.01) and superoxide dismutase (p<0.01) in skin cytosol when measured after 15 days and also after 12 weeks of the first 7,12-dimethylbenz (a) anthracene treatment. Lipid peroxidation measured with reference to thiobarbituric acid reactive substances in skin microsomes was significantly inhibited (p<0.05) in a dose dependent manner by diphenylmethyl selenocyanate. Considerable inhibition of the level of nitric oxide production in peritoneal macrophages was observed after 12 weeks (p<0.05). Thus the compound appears to exert chemopreventive activity in terms of papilloma formation, which may be through modulation of cutaneous lipid peroxidation, the phase II detoxifying enzyme system and nitric oxide production.