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mTOR is a serine/threonine kinase that regulates cell growth, metabolism, proliferation, and survival. mTOR complex-1 (mTORC1) and mTOR complex-2 (mTORC2) are critical mediators of the PI3K–AKT pathway, which is frequently mutated in many cancers, leading to hyperactivation of mTOR signaling. Although rapamycin analogues, allosteric inhibitors that target only the mTORC1 complex, have shown some clinical activity, it is hypothesized that mTOR kinase inhibitors, blocking both mTORC1 and mTORC2 signaling, will have expanded therapeutic potential. Here, we describe the preclinical characterization of CC-223. CC-223 is a potent, selective, and orally bioavailable inhibitor of mTOR kinase, demonstrating inhibition of mTORC1 (pS6RP and p4EBP1) and mTORC2 [pAKT(S473)] in cellular systems. Growth inhibitory activity was demonstrated in hematologic and solid tumor cell lines. mTOR kinase inhibition in cells, by CC-223, resulted in more complete inhibition of the mTOR pathway biomarkers and improved antiproliferative activity as compared with rapamycin. Growth inhibitory activity and apoptosis was demonstrated in a panel of hematologic cancer cell lines. Correlative analysis revealed that IRF4 expression level associates with resistance, whereas mTOR pathway activation seems to associate with sensitivity. Treatment with CC-223 afforded in vivo tumor biomarker inhibition in tumor-bearing mice, after a single oral dose. CC-223 exhibited dose-dependent tumor growth inhibition in multiple solid tumor xenografts. Significant inhibition of mTOR pathway markers pS6RP and pAKT in CC-223–treated tumors suggests that the observed antitumor activity of CC-223 was mediated through inhibition of both mTORC1 and mTORC2. CC-223 is currently in phase I clinical trials. Mol Cancer Ther; 14(6); 1295–305. ©2015 AACR.

High performance liquid chromatography-time-off-flight mass spectrometer (HPLC-TOFMS) technology coupled with partial least squares discriminant analysis (PLS-DA) processed by SIMCA-P software was applied to investigate serum endogenous metabolites alternations of valsartan in spontaneous hypertension rats (SHR). And MetPA platform was used to connect identified potential biomarkers in corresponding metabolic pathways to find possible therapeutic mechanism of valsartan. Valsartan significantly declined the blood pressure of SHRs (P0.05) at fourth week. The metabolic profiling significantly changed and four metabolites involved in G protein-coupled pathway were identified. Metabolomics is able to detect holistic and microcosmic alternations in organism, so as to elucidate therapeutic mechanism of drugs.

The export protein CRM1 is required for the nuclear export of a wide variety of cancer-related “cargo” proteins including p53, c-Abl, and FOXO-3A. Leptomycin B (LMB) is a highly specific inhibitor of CRM1 with significant in vitro potency but limited in vivo efficacy due to toxicity. We now report a series of semisynthetic LMB derivatives showing substantially improved therapeutic windows. Exposure of cancer cells to these compounds leads to a rapid and prolonged block of nuclear export and apoptosis. In contrast to what is observed in cancer cells, these agents induce cell cycle arrest, but not apoptosis, in normal lung fibroblasts. These new nuclear export inhibitors (NEI) maintain the high potency of LMB, are up to 16-fold better tolerated than LMB in vivo, and show significant efficacy in multiple mouse xenograft models. These NEIs show the potential of CRM1 inhibitors as novel and potent anticancer agents. [Cancer Res 2009;69(2):510–7]

Brain and leptomeningeal metastases are common in breast cancer patients and our current treatments are ineffective. Reovirus type 3 is a replication competent, naturally occurring virus that usurps the activated Ras-signaling pathway (or an element thereof) of tumor cells and lyses them but leaves normal cells relatively unaffected. In this study we evaluated reovirus as an experimental therapeutic in models of central nervous system (CNS) metastasis from breast cancer. We found all breast cancer cell lines tested were susceptible to reovirus, with > 50% of these cells lysed within 72 h of infection. In vivo neurotoxicity studies showed only mild local inflammation at the injection site and mild communicating hydrocephalus with neither diffuse encephalitis nor behavioral abnormalities at the therapeutically effective dose of reovirus (intracranial) (ie 10(7) plaque-forming units) or one dose level higher. In vivo, a single intratumoral administration of reovirus significantly reduced the size of tumors established from two human breast cancer cell lines and significantly prolonged survival. Intrathecal administration of reovirus also remarkably prolonged survival in an immunocompetent racine model of leptomeningeal metastases. These data suggest that the evaluation of reovirus as an experimental therapeutic for CNS metastases from breast cancer is warranted.

Thirty SHRs were obtained randomly to hypertension, model group, captopril group and Qingre jiangya capsule group. Ten Wistar rats were used as control group. The hippocampus tissue was removed to explore the damage of spontaneously hypertensive rats (SHR) and the protective effect of Qingre jiangya capsule after continuously administered for 14 days. And then the data were processed by principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA). The research results revealed captopril group was significantly different from the other three groups. The classification of other three groups is also very clear after captopril group removed. This suggested that Qingre jiangya capsule could improve the overall metabolism compared with captopril. Four metabolites were identified: dimethylglycine, glycerophosphocholine, aldosterone and noradrenaline. Hypertension hippocampus damage may mainly be expressed in tyrosine metabolism, aldosterone-regulated sodium, vascular smooth muscle contraction reabsorption, and Qingre jiangya capsule could reverse the hippocampus tissue damage of SHR.

The aim of the present study was to investigate the ultrastructural damage and the expression of heat shock protein 70 (HSP70) in the rat adenohypophysis following pulsed electromagnetic wave (PEMW) exposure. The rats were randomly divided into four groups: Sham PEMW exposure, 1 x 10(4) pulses of PEMW exposure, 1 x 10(5) pulses of PEMW exposure and 3 x 10(5) pulses of PEMW exposure. Whole body radiation of 1 x 10(4) pulses, 1 x 10(5) pulses and 3 x 10(5) pulses of PEMW were delivered with a field strength of 100 kV/m. The rats in each group (n=6 in each) were sacrificed 12, 24, 48 and 96 h after PEMW exposure. Transmission electron microscopy was then used to detect the ultrastructural changes and immunocytochemistry was used to examine the expression of HSP70. Cellular damage, including mitochondrial vacuolation occurred as early as 12 h after PEMW exposure.More severe cellular damages, including cell degeneration and necrosis, occurred 24 and 48 h after PEMW exposure. The PEMW-induced cellular damage increased as the number of PEMW pulses increased. In addition, the expression of HSP70 significantly increased following PEMW exposure and peaked after 12 h. These findings suggested that PEMW induced ultrastructural damages in the rat adenohypophysis and that HSP70 may have contributed to the PEMW-induced adenohypophyseal damage.

To investigate the effects of naringenin on the learning and memory ability of Alzheimer disease (AD) rats.30 male SD rats were randomly divided into control group (sham operation group), model group and naringenin group. AD model was established by injecting strepoztocin (3 mg/kg) twice into each of two intracerebroventriculas. Naringenin group were given intragastric administration of naringenin once a day for 3 weeks and the other two groups were given intragadtric administration of normal saline with the same dosage and time period. After 3 weeks, learning and memory ability in all the three groups were analyzed by Morris water maze, the activity of superoxide dismutase(SOD) and the content of malondialdehyde (MDA) of the rats' brain tissue was detected by chemical colorimetric determination. Observed the expressions of Abeta42 and Abeta40 by immunohistochemical method. The expression and degree of phosphorylation of tau protein was assayed by western blotting.1. Compared with the sham operation group, the mean escape latency of the model group was significantly prolonged (P0.05) and the time that rats were in the platform quadrant was significantly shortened (P0.0.5). On the contrary, compared with the model group, the mean escape latency of naringenin group was significantly shortened (P0.05) and the time that rats were in the platform quadrant was significantly extended (P0.005). 2. The level of MDA in the model group, compared with the sham operation group group, was significantly increased (P0.05). Whereas, that of naringenin group, compared with the model group, was significantly decreased compared with the sham operation group (P0.05). The activity of SOD in the naringenin group was significantly increased comparing with the model group (P0.05). 3. The expressions of Abeta40 and Abeta42 in model group were obviously up-regulated. Instead, the expressions of Abeta40 and Abeta42 in the naringenin group were significantly down regulated. 4. There was no significant difference in the expression of tau protein among each groups. Nevertheless, the phosphorylation of tau protein in the model group was significantly enhanced than that in the control group (P0.05), and the phosphorylation of tau protein in the naringenin group was significantly reduced than that in the model group (P0.05).Naringenin can improve learning and memory ability of model rats with Alzheimer disease through the approach of oxidative stress.

Human reovirus type 3 has been proposed to kill cancer cells with an activated Ras signaling pathway. The purpose of this study was to investigate the efficacy of reovirus in immunocompetent glioma animal models and safety/toxicity in immunocompetent animals, including nonhuman primates.Racine glioma cells 9L and RG2 were implanted s.c. or intracranially in Fisher 344 rats with or without reovirus antibodies, followed by treatment of reovirus. To study whether reovirus kills contralateral tumors in the brain and to determine viral distribution, we established an in situ dual tumor model followed by reovirus intratumoral inoculation only into the ipsilateral tumor. To evaluate neurotoxicity/safety of reovirus, Cynomolgus monkeys and immunocompetent rats were given intracranially with reovirus, and pathological examination and/or behavioral studies were done. Viral shedding and clinical biochemistry were systematically studied in monkeys.Intratumorally given reovirus significantly suppressed the growth of both s.c. and intracranially tumors and significantly prolonged survival. The presence of reovirus-neutralizing antibodies did not abort the reovirus' antitumor effect. Reovirus inhibited glioma growth intracranially in the ipsilateral but not the contralateral tumors; viral load in ipsilateral tumors was 15 to 330-fold higher than the contralateral tumors. No encephalitis or behavioral abnormalities were found in monkeys and rats given reovirus intracranially. No treatment-related clinical biochemistry changes or diffuse histopathological abnormality were found in monkeys inoculated intracranially with Good Manufacturing Practice prepared reovirus. Microscopic changes were confined to the region of viral inoculation and were dose related, suggesting reovirus intracranially was well tolerated in nonhuman primates.These data show the efficacy and safety of reovirus when it is used in the treatment of gliomas in immunocompetent hosts. Inoculation of reovirus into the brain of nonhuman primates did not produce significant toxicities.

Medulloblastoma (MB), the most common pediatric brain tumor, is a highly malignant disease with a 5-year survival rate of only 60%. Tumor cells invade surrounding tissue and disseminate through cerebral spinal fluid, making treatment difficult. Human reovirus type 3 exploits an activated Ras pathway in tumor cells to support productive infection as an oncolytic virus. Here, we examined the ability of human reovirus to kill MB cells lines and surgical specimens in vitro and inhibit tumor growth/metastases in vivo. Most human MB cell lines tested (five of seven = 71.4%), two MB cell lines derived from spontaneously arising tumors in Patched-1(+/-) mice (two of two = 100%) and three MB primary cultures derived from surgical specimens, were susceptible to reovirus infection. Reovirus was internalized and transcribed in both susceptible and resistant cell lines. However, viral protein synthesis was restricted to cell lines with higher levels of activated Ras, suggesting that Ras plays a critical role in reovirus oncolysis in MB. Using an in vivo Daoy orthotopic animal model, we found that a single i.t. injection of reovirus dramatically prolonged survival compared with controls (160 versus 70 days, respectively; P = 0.0003). Repeating this experiment with GFP-labeled Daoy cells and multiple i.t. administrations of reovirus, we again found prolonged survival and a dramatic reduction in spinal and leptomeningeal metastases (66.7% in control injections versus 0.0% in the live virus group). These data suggest that this oncolytic virus may be a potentially effective novel therapy against human MB. Its ability to reduce metastases to the spinal cord could allow a reduction in the dose/field of total neuroaxis cerebral-spinal radiotherapy currently used to treat/prevent cerebral spinal fluid dissemination.