Ponatinib Shows Potent Antitumor Activity in Small Cell Carcinoma of the Ovary Hypercalcemic Type (SCCOHT) through Multikinase Inhibition.

Purpose: Small cell carcinoma of the ovary, hypercalcemic type (SCCOHT) is a rare, aggressive ovarian cancer in young women that is universally driven by loss of the SWI/SNF ATPase subunits SMARCA4 and SMARCA2. A great need exists for effective targeted therapies for SCCOHT.Experimental Design: To identify underlying therapeutic vulnerabilities in SCCOHT, we conducted high-throughput siRNA and drug screens. Complementary proteomics approaches profiled kinases inhibited by ponatinib. Ponatinib was tested for efficacy in two patient-derived xenograft (PDX) models and one cell-line xenograft model of SCCOHT.Results: The receptor tyrosine kinase (RTK) family was enriched in siRNA screen hits, with FGFRs and PDGFRs being overlapping hits between drug and siRNA screens. Of multiple potent drug classes in SCCOHT cell lines, RTK inhibitors were only one of two classes with selectivity in SCCOHT relative to three SWI/SNF wild-type ovarian cancer cell lines. We further identified ponatinib as the most effective clinically approved RTK inhibitor. Reexpression of SMARCA4 was shown to confer a 1.7-fold increase in resistance to ponatinib. Subsequent proteomic assessment of ponatinib target modulation in SCCOHT cell models confirmed inhibition of nine known ponatinib target kinases alongside 77 noncanonical ponatinib targets in SCCOHT. Finally, ponatinib delayed tumor doubling time 4-fold in SCCOHT-1 xenografts while reducing final tumor volumes in SCCOHT PDX models by 58.6% and 42.5%.Conclusions: Ponatinib is an effective agent for SMARCA4-mutant SCCOHT in both in vitro and in vivo preclinical models through its inhibition of multiple kinases. Clinical investigation of this FDA-approved oncology drug in SCCOHT is warranted. Clin Cancer Res; 24(8); 1932-43. ©2018 AACR.

Curcumin and quercetin trigger apoptosis during benzo(a)pyrene-induced lung carcinogenesis.

The aim of the present study was to assess the cumulative effects of curcumin and quercetin in inducing apoptosis during benzo(a)pyrene (BP) (100 mg/Kg body weight)-induced lung carcinogenesis in mice. BP treatment resulted in a significant increase in the protein expression of Bcl-2 whereas expression of Bax was significantly decreased. Further, BP treatment brought about a significant decrease in the activities of caspase 3, caspase 9 as well as the number of apoptotic cells. Interestingly, separate as well as combined supplementation of curcumin (60 mg/kg body weight) and quercetin (40 mg/kg body weight) to BP-treated animals resulted in a significant decrease in the protein expression of Bcl-2 but caused a significant increase in the protein expression of Bax along with a noticeable improvement in the number of apoptotic cells. Also, supplementation with curcumin and quercetin separately to BP-treated mice brought a significant improvement in the enzyme activities of caspase 9 as well as caspase 3 but the improvement was more pronounced following combined treatment. Therefore, curcumin and quercetin, if given in combination shall exhibit enhanced chemopreventive potential against development of lung carcinogenesis by stimulating the apoptotic machinery.

Study to evaluate molecular mechanics behind synergistic chemo-preventive effects of curcumin and resveratrol during lung carcinogenesis.

BACKGROUND: The combination approach is the future of the war against cancer and the present study evaluated molecular mechanics behind the synergistic effects of curcumin and resveratrol during lung carcinogenesis. METHODS: The mice were segregated into five groups which included normal control, Benzo[a]pyrene[BP] treated, BP+curcumin treated, BP+resveratrol treated and BP+curcumin+resveratrol treated. RESULTS: The morphological analyses of tumor nodules confirmed lung carcinogenesis in mice after 22 weeks of single intra-peritoneal[i.p] injection of BP at a dose of 100 mg/Kg body weight. The BP treatment resulted in a significant increase in the protein expressions of p53 in the BP treated mice. Also, a significant increase in the protein expression of phosphorylated p53[ser15] confirmed p53 hyper-phosphorylation in BP treated mice. On the other hand, enzyme activities of caspase 3 and caspase 9 were noticed to be significantly decreased following BP treatment. Further, radiorespirometric studies showed a significant increase in the 14C-glucose turnover as well as 14C-glucose uptake in the lung slices of BP treated mice. Moreover, a significant rise in the cell proliferation was confirmed indirectly by enhanced uptake of 3H-thymidine in the lung slices of BP treated mice. Interestingly, combined treatment of curcumin and resveratrol to BP treated animals resulted in a significant decrease in p53 hyper-phosphorylation, 14C glucose uptakes/turnover and 3H-thymidine uptake in the BP treated mice. However, the enzyme activities of caspase 3 and caspase 9 showed a significant increase upon treatment with curcumin and resveratrol. CONCLUSION: The study, therefore, concludes that molecular mechanics behind chemo-preventive synergism involved modulation of p53 hyper-phosphorylation, regulation of caspases and cellular metabolism enzymes.

Premature mitochondrial senescence and related ultrastructural changes during lung carcinogenesis modulation by curcumin and resveratrol.

The present study attempted to explore the efficacy of curcumin and resveratrol in modulating premature mitochondria senescence and ultrastructural changes during lung carcinogenesis. The mice were segregated into 5 groups, which included normal control, benzo[a]pyrene (BP) treated, BP + curcumin (C) treated, BP + resveratrol (R) treated, and BP + C + R treated groups. Animals were given a single ip injection of benzo[a]pyrene in corn oil at a dose level of 100 mg/kg body weight. Treatments of curcumin and resveratrol were given orally in drinking water at a dose level of 60 mg/kg body weight and 5.7 µg/mL drinking water, respectively, 3 times a week for a total duration of 22 weeks. Ultrastructure of BP-treated mice revealed disruptions in cellular integrity along with nuclear deformation and premature mitochondrial senescence. Interestingly, supplementation of curcumin and resveratrol individually resulted in improvement of ultrahistoarchitecture of BP-treated mice but the improvement was much greater with combined supplementation of phytochemicals. Further, benzo[a]pyrene treatment revealed alterations in lung histoarchitecture, which, however, was improved appreciably following combined supplementation with curcumin and resveratrol. The present study concludes that combined supplementation with curcumin and resveratrol effectively modulates histoarchitecture as well as ultrahistoarchitecture during benzo[a]pyrene-induced lung carcinogenesis in mice. Cancer is a public health problem worldwide. Lung cancer is a major cause of mortality throughout the world and is responsible for the deaths of more than one million people annually. Phytochemicals have shown great potential in preventing the occurrence of cancer and other chronic diseases that result from oxidative stress induced by free radicals. Phytochemicals are nonnutritive products of plants and, being nontoxic, are presently being studied the world over for their chemopreventive actions in controlling various diseases, including cancer. In the present study, curcumin and resveratrol are the phytochemicals of interest. Curcumin, a polyphenol, has been reported to have anti-invasive properties. Further, curcumin has been shown to activate apoptotic machinery in patients with lung cancer. On the other hand, resveratrol (trans-3,4,5- thihydroxystibene) is a phytoalexin that is present naturally in grapes as well as in a variety of medicinal plants and has been shown to exhibit antioxidant activity with a potential to induce apoptosis.

Efficacy of zinc as a nutritional supplement in ameliorating chlorpyrifos-induced neurotoxicity in rats.

This study aimed to evaluate the efficacy of zinc as a nutritional supplement in preventing chlorpyrifos-induced neurotoxicity in rats. The rats were segregated into 4 groups, which included normal controls and chlorpyrifos-treated, zinc-treated, and chlorpyrifos- and zinc-treated animals. Eight weeks of chlorpyrifos treatment resulted in a significant increase in the levels of lipid peroxidation (LPO) and reactive oxygen species (ROS) in both cerebellum and cerebrum as compared to normal animals. On the contrary, the activities of glutathione-s-transferase (GST), glutathione reductase (GR), superoxide dismutase (SOD), and reduced glutathione (GSH) levels were found to be significantly decreased following chlorpyrifos treatment. Furthermore, chlorpyrifos resulted in anxiety in rats as observed by the elevated plus maze test. In addition, an appreciable decrease was noticed in the muscular as well as locomotor activity of chlorpyrifos-treated animals was noticed by rotarod and actophotometer tests, respectively. However, zinc supplementation to chlorpyrifos-treated animals brought back the already raised levels of LPO and ROS to near normal limits in cerebrum. Moreover, zinc treatment to the chlorpyrifos-treated animals also resulted in a significant improvement in the levels of reduced glutathione, and enzyme activities of GST in both cerebrum as well as cerebellum. Also, improvement was observed in the behavior of chlorpyrifos-treated animals upon zinc supplementation. The present study thus concludes that zinc has potential to act as a neuroprotectant against pesticide-induced neurodegenerative and behavioral disorders but further investigations need to be conducted to understand the exact mechanism of neuroprotection.

Curcumin and resveratrol synergistically stimulate p21 and regulate cox-2 by maintaining adequate zinc levels during lung carcinogenesis.

This study explored the efficacy of curcumin and resveratrol in maintaining adequate zinc levels to regulate p21 and cyclooxygenase-2 (cox-2) during benzo[a]pyrene (BP)-induced lung carcinogenesis. The mice were segregated into five groups, which included normal control, BP treated, BP plus curcumin treated, BP plus resveratrol treated, and BP plus curcumin plus resveratrol-treated groups. BP treatment resulted in a significant decrease in the zinc levels and protein expression of p21. On the contrary, the enzyme activity of cox-2 showed a significant increase in the BP-treated mice. Interestingly, combined supplementation of curcumin and resveratrol to BP-treated mice resulted in an appreciable improvement in the zinc levels and protein expression of p21. In contrast, synergistic supplementation with phytochemicals resulted in a significant decrease in the enzyme activities of cox-2 in BP-treated mice. This study, therefore, concludes that combined treatment with curcumin and resveratrol maintains adequate zinc levels and regulates inflammation by cox-2 and cell cycle arrest by p21 during lung carcinogenesis in mice.

Altered uptake and biological half-lives of 65Zn on arsenic exposure--modulation by zinc treatment.

The present study revealed the effects of zinc on the biokinetics of (65)Zn in rats following arsenic intoxication. The animals were segregated into four groups: group I--untreated controls, group II--arsenic treated (100 ppm as NaAsO(2) in drinking water), group III--zinc treated (227 mg ZnSO(4) per liter drinking water), and group IV--arsenic + zinc treated. Each rat was injected intraperitoneally with 1.85 MBq radioactivity of (65)Zn following 3 months of different treatments, and the radioactivity was determined using a suitably shielded scintillation counter. Arsenic treatment showed a significant increase in the fast component (Tb(1)) of the biological half-life of (65)Zn in liver, which remained unaltered in the whole body. Furthermore, arsenic treatment decreased significantly the slow component (Tb(2)) in the whole body, which remained unchanged in the liver. However, zinc supplementation to arsenic-treated rats normalized Tb(1) in the liver, but caused no change in Tb(2) in the whole body. Furthermore, the uptake values of (65)Zn were significantly increased in the liver, brain, kidney, and intestine following arsenic treatment, and the values in the liver and brain were decreased by zinc. Hence, zinc plays a significant role in regulating the biokinetics of (65)Zn in the liver and the whole body of arsenic-intoxicated rats.

Protective role of zinc in ameliorating arsenic-induced oxidative stress and histological changes in rat liver.

The aim of present work was to gain insight into the role of dietary zinc in ameliorating the adverse effects caused by arsenic on rat liver. Male Wistar rats received arsenic alone in the form of sodium arsenite in drinking water at a dose level of 100 ppm, zinc alone in the form of zinc sulfate in drinking water at a dose level of 227 mg/L, or arsenic + zinc treatments in the combined group for a total duration of 3 months. Arsenic treatment resulted in a significant increase in lipid peroxidase (LPO); however, glutathione (GSH) levels and the activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), and catalase (CAT) were found to be significantly decreased following arsenic treatment. Furthermore, arsenic treatment resulted in a significant decrease in hepatic zinc levels. Histological studies showed well-differentiated signs of focal hepatitis, lobular inflammation, prominent hepatocyte degeneration, and severe periportal necrosis. Administration of zinc to arsenic-treated rats significantly decreased the level of LPO but increased the level of GSH compared with arsenic-treated rats. Further, the zinc level and activities of SOD, GPx, GR, and CAT were found to be significantly increased following zinc treatment. The administration of zinc to arsenic-treated rats caused signs of improvement in liver histoarchitecture, but a few focal areas of degeneration and necrosis were still occasionally seen. In conclusion, the results of this study suggest that zinc can be beneficial against arsenic-induced hepatotoxicity in rats.

Modulatory effects of curcumin and resveratrol on lung carcinogenesis in mice.

The aim of the present study is to explore the chemopreventive potential of curcumin and resveratrol during promotional phase of benzo(a)pyrene (BP) induced lung carcinogenesis in mice. The mice were segregated into five groups which included normal control, BP-treated, BP+curcumin-treated, BP+resveratrol-treated and BP+curcumin+resveratrol-treated groups. The BP treatment resulted in a significant increase in the levels of lipid peroxidation (LPO). On the other hand, reduced glutathione (GSH) levels and the activities of superoxide dismutase (SOD) were found to be significantly decreased following BP treatment. Administration of curcumin to BP-treated mice decreased the levels of LPO significantly. Further, treatment of resveratrol to BP-treated mice significantly elevated the activities of SOD. Combined treatment of curcumin and resveratrol, kowever, showed significant improvement in LPO and GSH levels as well as in the activities of SOD. Histo-architectural studies showed well-differentiated signs of lung carcinogenesis following BP administration to mice. Although treatments with resveratrol and curcumin given separately to BP-treated mice showed appreciable improvement in the histo-architecture of the lung, combined treatment resulted in a noticeable improvement in the lung histo-architecture.

Role of zinc in modulating histo-architectural and biochemical alterations during dimethylhydrazine (DMH)-induced rat colon carcinogenesis.

The aim of the present work was to gain insight into the putative anticancer effect of dietary zinc during 1,2 dimethylhydrazine (DMH)-induced colon carcinogenesis. The rats were segregated into four groups, namely, normal control, DMH-treated, zinc-treated, and (DMH + zinc)-treated. Colon carcinogenesis was induced through weekly subcutaneous injections of DMH (30 mg/kg body weight) for 12 weeks. Zinc in the form of zinc sulfate was supplemented to rats at a dose level of 227 mg/L in drinking water, ad libitum for the entire duration of the study. The effects of different treatments were studied on lipid peroxidation (LPO), reduced glutathione (GSH), and antioxidative enzymes, which included superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), glutathione reductase (GR), as well as on the histoarchitecture of the colon. A total of 12 weeks of DMH treatment resulted in a significant increase in LPO. GSH levels and the activities of SOD, CAT, and GST were found to be significantly decreased following DMH treatment. A significant elevation in the activity of GR was observed following 12 weeks of DMH treatment. Histopathological studies showed well-differentiated signs of dysplasia, which included nuclei enlargement, epithelial thickening, and nuclear pleomorphism indicative of promotional phase of colon carcinogenesis in DMH-administered rats. Administration of zinc to DMH-treated rats decreased the levels of LPO and GSH significantly, but the activities of SOD and CAT were found to be significantly increased following zinc treatment. Zinc supplementation along with DMH treatment did not reveal any significant change in the activity of GR but significantly improved the activity of GST, which was depressed following DMH treatment. Also, zinc treatment in DMH-treated rats showed signs of great improvement, but structureless masses of the cells and hyperchromic nuclei were still visible occasionally. In conclusion, the results of this study suggest that zinc has a positive beneficial effect against chemically DMH-induced colonic preneoplastic progression in rats.