Intraoperative hypotension and perioperative acute ischemic stroke in patients having major elective non-cardiovascular non-neurological surgery.

PURPOSE: The association between intraoperative hypotension and perioperative acute ischemic stroke is not well described. We hypothesized that intraoperative hypotension would be associated with perioperative acute ischemic stroke. METHODS: Four-year retrospective cohort study of elective non-cardiovascular, non-neurological surgical patients. Characteristics of patients who had perioperative acute ischemic stroke were compared against those of patients who did not have acute ischemic stroke. Multivariable logistic regression was used to determine whether hypotension was independently associated with increased odds of perioperative acute ischemic stroke. RESULTS: Thirty-four of 9816 patients (0.3%) who met study inclusion criteria had perioperative acute ischemic stroke. Stroke patients were older and had more comorbidities including hypertension, coronary artery disease, diabetes mellitus, active tobacco use, chronic obstructive pulmonary disease, cerebral vascular disease, atrial fibrillation, and peripheral vascular disease (all P < 0.05). MAP < 65 mmHg was not associated with increased odds of acute ischemic stroke when modeled as a continuous or categorical variable. MAP < 60 mmHg for more than 20 min was independently associated with increased odds of acute ischemic stroke, OR = 2.67 [95% CI = 1.21 to 5.88, P = 0.02]. CONCLUSION: Our analysis suggests that when MAP is less than 60 mmHg for more than 20 min, there is increased odds of acute ischemic stroke. Further studies are needed to determine what MAP should be targeted during surgery to optimize cerebral perfusion and limit ischemic stroke risk.

HDAC9 overexpression confers invasive and angiogenic potential to triple negative breast cancer cells via modulating microRNA-206.

Triple negative breast cancer (TNBC) is among the most aggressive breast cancer subtypes with poor prognosis. The purpose of this study is to better understand the molecular basis of TNBC as well as develop new therapeutic strategies. Our results demonstrate that HDAC9 is overexpressed in TNBC compared to non-TNBC cell lines and tissues and is inversely proportional with miR-206 expression levels. We show that HDAC9 selective inhibition blocked the invasion of TNBC cells in vitro and repressed the angiogenesis shown via in vivo Matrigel plug assays. Subsequent HDAC9 siRNA knockdown was then shown to restore miR-206 while also decreasing VEGF and MAPK3 levels. Furthermore, the inhibition of miR-206 neutralized the action of HDAC9 siRNA on decreasing VEGF and MAPK3 levels. This study highlights HDAC9 as a mediator of cell invasion and angiogenesis in TNBC cells through VEGF and MAPK3 by modulating miR-206 expression and suggests that selective inhibition of HDAC9 may be an efficient route for TNBC therapy.

MicroRNA-30c-regulated HDAC9 mediates chemoresistance of breast cancer.

PURPOSE: Although histone deacetylase (HDAC) inhibitors have been shown to effectively induce the inhibition of proliferation and migration in breast cancer, the mechanism of HDAC9's contribution to chemoresistance remains poorly understood. The aim of this study was to investigate the role of miR-30c-regulated HDAC9 in chemoresistance of breast cancer and to determine the potential of selective inhibition of HDAC9 in sensitizing resistant breast cancer cells to chemotherapy. METHODS: Expression levels of HDAC9 and miR-30c were measured in breast cancer cells and tissues using quantitative PCR analysis. The effect of selective inhibition of HDAC9 on sensitizing MDR cells to chemotherapy was assessed. MiR-30c/HDAC9 pathways' potential to mediate chemoresistance was analyzed. RESULTS: Our studies show that HDAC9 was significantly up-regulated in chemoresistant breast cancer cell lines compared to a chemosensitive cell line and was inversely correlated with the levels of miR-30c. MiR-30c mimics and HDAC9 inhibitors reversed the chemoresistance of multidrug-resistant breast cancer cells. CONCLUSIONS: These results indicate that the mechanism of chemoresistance reversal with selective HDAC inhibition was partially realized by regulating miR-30c via directly targeting HDAC9. Our findings suggest that the miR-30c/HDAC9 signaling axis could be a novel and potential therapeutic target in chemoresistant breast cancer.

YAP1/TAZ-TEAD transcriptional networks maintain skin homeostasis by regulating cell proliferation and limiting KLF4 activity.

The Hippo TEAD-transcriptional regulators YAP1 and TAZ are central for cell renewal and cancer growth; however, the specific downstream gene networks involved in their activity are not completely understood. Here we introduce TEADi, a genetically encoded inhibitor of the interaction of YAP1 and TAZ with TEAD, as a tool to characterize the transcriptional networks and biological effects regulated by TEAD transcription factors. Blockage of TEAD activity by TEADi in human keratinocytes and mouse skin leads to reduced proliferation and rapid activation of differentiation programs. Analysis of gene networks affected by TEADi and YAP1/TAZ knockdown identifies KLF4 as a central transcriptional node regulated by YAP1/TAZ-TEAD in keratinocyte differentiation. Moreover, we show that TEAD and KLF4 can regulate the activity of each other, indicating that these factors are part of a transcriptional regulatory loop. Our study establishes TEADi as a resource for studying YAP1/TAZ-TEAD dependent effects.

Development of CXCR4 modulators based on the lead compound RB-108.

The CXCR4/CXCL12 axis plays prominent roles in tumor metastasis and inflammation. CXCR4 has been shown to be involved in a variety of inflammation-related diseases. Therefore, CXCR4 is a promising potential target to develop novel anti-inflammatory agents. Taking our previously discovered CXCR4 modulator RB-108 as the lead compound, a series of derivatives were synthesized structurally modifying and optimizing the amide and sulfamide side chains. The derivatives successfully maintained potent CXCR4 binding affinity. Furthermore, compounds IIb, IIc, IIIg, IIIj, and IIIm were all efficacious in inhibiting the invasion of CXCR4-positive cells, displaying a much more potent effect than the lead compound RB-108. Notably, compound IIIm significantly decreased carrageenan-induced swollen volume and paw thickness in a mouse paw edema model. More importantly, IIIm exhibited satisfying PK profiles with a half-life of 4.77 h in an SD rat model. In summary, we have developed compound IIIm as a new candidate for further investigation based on the lead compound RB-108.

HDAC inhibitor suppresses proliferation and invasion of breast cancer cells through regulation of miR-200c targeting CRKL.

Although histone deacetylase (HDAC) inhibitors have been shown to effectively induce the inhibition of proliferation and migration in breast cancer, the anticancer mechanism remains poorly understood. Our studies show that miR-200c was significantly downregulated in breast cancer cell lines compared to normal cell lines and inversely correlated with the levels of class IIa HDACs and CRKL. HDAC inhibitors and the ectopic expression of miR-200c as tumor suppressors inhibited the proliferation, invasion, and migration of breast cancer cells by downregulating CRKL. These results indicate that the anticancer mechanism of HDAC inhibitor was realized partially by regulating miR-200c via CRKL targeting. Our findings suggest that the HDAC-miR200c-CRKL signaling axis could be a novel diagnostic marker and potential therapeutic target in breast cancer.

Anti-inflammatory hybrids of secondary amines and amide-sulfamide derivatives.

The CXCR4/CXCL12 chemokine axis can chemotactically accumulate inflammatory cells to local tissues and regulate the release of inflammatory factors. Developing novel CXCR4 modulators may provide a desirable strategy to control the development of inflammation. A series of novel hybrids were designed by integrating the key pharmacophores of three CXCR4 modulators. The majority of compounds displayed potent CXCR4 binding affinity. Compound 7a exhibited 1000-fold greater affinity than AMD3100 and significantly inhibited invasion of CXCR4-positive tumor cells. Additionally, compound 7a blocked mice ear inflammation by 67% and suppressed the accumulation of inflammatory cells in an in vivo mouse ear edema evaluation. Western blot analyses revealed that 7a inhibited the CXCR4/CXCL12-mediated phosphorylation of Akt and p44 in a dose-dependent manner. Moreover, compound 7a had no observable cytotoxicity and displayed a favorable plasma stability in our preliminary pharmacokinetic study. These results confirmed that this is a feasible method to develop CXCR4 modulators for the regulation and reduction of inflammation.

Novel anti-inflammatory agents targeting CXCR4: Design, synthesis, biological evaluation and preliminary pharmacokinetic study.

CXCR4 plays a crucial role in the inflammatory disease process, providing an attractive means for drug targeting. A series of novel amide-sulfamide derivatives were designed, synthesized and comprehensively evaluated. This new scaffold exhibited much more potent CXCR4 inhibitory activity, with more than 70% of the compounds showed notably better binding affinity than the reference drug AMD3100 in the binding assay. Additionally, in the Matrigel invasion assay, most of our compounds significantly blocked the tumor cell invasion, demonstrating superior efficacy compared to AMD3100. Furthermore, compound IIj blocked mice ear inflammation by 75% and attenuated ear edema and damage substantially in an in vivo model of inflammation. Western blot analyses revealed that CXCR4 modulator IIj significantly blocked CXCR4/CXCL12-mediated phosphorylation of Akt. Moreover, compound IIj had no observable cytotoxicity and displayed a favourable plasma stability in our preliminary pharmacokinetic study. The preliminary structure-activity relationships were also summarized. In short, this novel amide-sulfamide scaffold exhibited potent CXCR4 inhibitory activity both in vitro and in vivo. These results also confirmed that developing modulators targeting CXCR4 provides an exciting avenue for treatment of inflammation.

Development of CXCR4 modulators by virtual HTS of a novel amide-sulfamide compound library.

CXCR4 plays a crucial role in recruitment of inflammatory cells to inflammation sites at the beginning of the disease process. Modulating CXCR4 functions presents a new avenue for anti-inflammatory strategies. However, using CXCR4 antagonists for a long term usage presents potential serious side effect due to their stem cell mobilizing property. We have been developing partial CXCR4 antagonists without such property. A new computer-aided drug design program, the FRESH workflow, was used for anti-CXCR4 lead compound discovery and optimization, which coupled both compound library building and CXCR4 docking screens in one campaign. Based on the designed parent framework, 30 prioritized amide-sulfamide structures were obtained after systemic filtering and docking screening. Twelve compounds were prepared from the top-30 list. Most synthesized compounds exhibited good to excellent binding affinity to CXCR4. Compounds Ig and Im demonstrated notable in vivo suppressive activity against xylene-induced mouse ear inflammation (with 56% and 54% inhibition). Western blot analyses revealed that Ig significantly blocked CXCR4/CXCL12-mediated phosphorylation of Akt. Moreover, Ig attenuated the amount of TNF-α secreted by pathogenic E. coli-infected macrophages. More importantly, Ig had no observable cytotoxicity. Our results demonstrated that FRESH virtual high throughput screening program of targeted chemical class could successfully find potent lead compounds, and the amide-sulfamide pharmacophore was a novel and effective framework blocking CXCR4 function.