These results support the possibility that excitatory output of sevoflurane-potentiated gamma-aminobutyric acid type A/glycine systems may contribute to epileptogenic and neurotoxic effects in early postnatal rats.

This is the first study to demonstrate DCA can effectively sensitize wild-type and over expressing Bcl-2 human prostate cancer cells to radiation by modulating the expression of key members of the Bcl-2 family. Together, these findings warrant further evaluation of the combination of DCA and irradiation.

These data show that CXCR4 antagonists represent a valuable addition to the cancer therapeutic arsenal. Such agents may have beneficial synergistic dual-effects in reducing tumor cell proliferation directly, and indirectly through perturbation of the tumor microenvironment. Further studies of the novel CTCE-9908 compound in prostate and other solid tumor inhibition are warranted. Prostate 69: 1460-1469, 2009. (c) 2009 Wiley-Liss, Inc.

Recently a convincing body of evidence has accumulated, suggesting that the over-expression of carbonic anhydrase isozyme IX (CA IX) in some cancers contributes to the acidification of the extracellular matrix, which in turn promotes the growth and metastasis of the tumor. These observations have made CA IX an attractive drug target for the selective treatment of certain cancers. Currently there is no available x-ray crystal structure of CA IX and this has hampered the rational design of selective CA IX inhibitors. In light of these observations and based on structural alignment homology, using the crystal structure CA II and the sequence of CA IX, a double mutant of CA II with Ala 65 replaced by Ser and Asn 67 replace by Gln has been constructed to resemble the active site of CA IX. This CA IX mimic has been characterized kinetically using 18 O-exchange and structurally using x-ray crystallography, alone and in complex with five CA sulfonamide based inhibitors; acetazolamide, benzolamide, chlorzolamide, ethoxzolamide, and methazolamide, and compared to CA II. This structural information has been evaluated in relationship to inhibition studies and in vitro cytotoxicity assays and shows a correlated structure-activity relationship. Kinetic and structural studies of CA II and CA IX mimic reveal chlorzolamide to be a more potent inhibitor of CA IX inducing an active site conformational change upon binding. Additionally, chlorzolamide appears to be cytotoxic to prostate cancer cells. This preliminary study demonstrates that the CA IX mimic may provide a useful model to design more isozyme specific CA IX inhibitors which may lead to development of new therapeutic treatments of some cancers.Carbonic anhydrases (CAs) 1 are zinc-metalloenzymes that catalyze the reversible interconversion of CO 2 and HCO 3 -(1). Since their discovery, the CAs have been extensively studied due to their important physiological functions in all kingdoms of life. This family of enzymes † This work was supported by a grant (GM25154 to D.N.S. and R.M.) from the National Institutes of Health and the Maren Foundation (to R.M.). ‡ Coordinates and structure factors have been deposited in the Protein Data Bank as 3DC9.pdb and 3DC9.sf, 3DCS.pdb and 3DCS.sf, 3DCC.pdb and 3DCC.sf, 3DC3.pdb and 3DC3.sf, 3DCW.pdb and 3DCW.sf, 3DBU.pdb and 3DBU.sf, 3DAZ.pdb and 3DAZ.sf, 3D9Z.pdb and 3D9Z.sf, 3DD0.pdb and 3DD0.sf, and 3D8W.pdb and 3D8W.sf.

Background We sought whether subjects with pathophysiological conditions that are characterized by elevated levels of aldosterone have increased susceptibility to the side effects of neonatal anesthesia with sevoflurane. Methods Postnatal day 4–20 (P4–P20) rats were exposed to 6% and 2.1% sevoflurane for 3 min and 60–360 min, respectively. Exogenous aldosterone was administered to imitate pathophysiological conditions with elevated levels of aldosterone. Results Six hours of anesthesia with sevoflurane on P4–P5 resulted in more than 30-fold increase in serum levels of aldosterone (7.02 ± 1.61 ng/dl vs. 263.75 ± 22.31 ng/dl, mean ± SE, n = 5–6) and reduced prepulse inhibition of the acoustic startle response (F(2,37)= 5.66, P<0.001). Administration of exogenous aldosterone during anesthesia with sevoflurane further enhanced seizure-like electroencephalogram patterns in neonatal rats (48.25±15.91 s vs. 222.00 ± 53.87 s, mean± SE, n = 4), but did not affect electroencephalographic activity in older rats. Exogenous aldosterone increased activation of caspase-3 (F(3,28)=11.02, P<0.001) and disruption of prepulse inhibition of startle (F(3,46)=6.36; P= 0.001) caused by sevoflurane. Intracerebral administration of oxytocin receptor agonists resulted in depressed seizure-like electroencephalogram patterns (F(2,17)=6.37, P=0.009), reduced activation of caspase-3 ((t(11) = 2.83, P = 0.016) and disruption of PPI of startle (t(7) = −2.9; P = 0.023) caused by sevoflurane. Conclusions These results suggest that adverse developmental effects of neonatal anesthesia with sevoflurane may involve both central and peripheral actions of the anesthetic. Subjects with elevated levels of aldosterone may be more vulnerable, while intracerebral oxytocin receptor agonists may be neuroprotective.

Angiogenesis is an integral part of both the pulmonary inflammatory response to chronic exposure to cigarette smoke and the lung tissue remodeling associated with cigarette smoke-induced chronic obstructive pulmonary disease (COPD). To investigate the role of angiogenesis in the pathogenesis of COPD, we evaluated the effect of cigarette smoke extract (CSE) on angiogenesis of pulmonary artery endothelial cells (PAEC). Incubation of PAEC with 2.5-10% CSE resulted in a dose-dependent inhibition of endothelial monolayer wound repair. CSE also caused inhibition of tube formation on Matrigel, migration in a Boyden chamber, and proliferation of PAEC. Because calpain, a family of calcium-dependent intracellular proteases, mediates cytoskeletal signaling in endothelial motility, we explored the role of calpain in the CSE-induced inhibition of endothelial angiogenesis. Incubation of CSE resulted in a dose-dependent decrease in calpain activity. Calpain inhibitor-1, a specific inhibitor of calpain, potentiates inhibitory effect of CSE on the endothelial monolayer wound repair, tube formation, cell migration, and cell proliferation. Transfection of PAEC with antisense oligodeoxyribonucleotides of calpastatin, the major endogenous calpain inhibitor, prevented CSE-induced increase in calpastatin protein content and CSE-induced decreases in calpain activity. It also prevented CSE-induced decreases in monolayer wound repair, tube formation, and migration. These results suggest that CSE attenuates angiogenesis of PAEC and the mechanism involves inhibition of calpain. Impaired angiogenesis may impede the repair process in the lungs of cigarette smokers and contribute to the altered structural remodeling observed in the lungs of patients with cigarette smoke-related COPD.

This is the first study to demonstrate that docetaxel and bortezomib in combination can effectively sensitize Bcl-2-overexpressing human prostate cancer cells to radiation effects by modulating the expression of key members of the Bcl-2 family. Together, these findings warrant further evaluation of the combination of docetaxel and bortezomib in prostate cancer.

Together, these results demonstrate that Bcl-2 can regulate tumoral angiogenesis and lymphangiogenesis and suggest that therapy targeted at Bcl-2 expression, angiogenesis, and lymphangiogenesis may synergistically modulate tumor growth and confirm that Bcl-2 is a pivotal target for cancer therapy.