Anti-neoplastic sulfonamides alter the metabolic homeostasis and disrupt the suppressor activity of regulatory T cells.

Regulatory T cells (Tregs) are essential to maintain self-tolerance and immune homeostasis but, as components of the tumor microenvironment (TME), are also a major barrier to effective cancer immunosurveillance and immunotherapy. FH535 and its derivative Y3 are two N-aryl-benzene-sulfonamides (NABs) that inhibit HCC cell proliferation and tumor progression. However, the impact of NABs on the immune cells in the TME is not yet known. Analyses of explanted livers from patients with hepatocellular carcinoma (HCC) showed that high levels of tumor-infiltrating Tregs were associated with poor tumor differentiation. These results lead us to investigate the immunomodulatory effects of NABs in regulatory and effector T cells. Exposure of primary human Tregs to NABs induced a rapid but temporary increase of cell expansion, a gradual disruption of suppressor activity, and concomitant bioenergetics and autophagic flux dysregulations. In contrast to Tregs, no gross effects were observed in effector T cells. Addition of Rapamycin prevented the functional decay of Tregs and restored their metabolic profile, suggesting that NAB effects require the integrity of the mTOR pathway. This study revealed the immunomodulatory properties of NABs with a preferential impact on Treg activity and provided novel insights into the anti-tumor potential of sulfonamides.

Mitochondrial uncoupling and the disruption of the metabolic network in hepatocellular carcinoma.

BACKGROUND: Hepatocellular Carcinoma (HCC) is the third most common cause of cancer related death worldwide. Adequate treatment options for patients with advanced HCC are currently limited. MATERIALS AND METHODS: We studied the anti-HCC effect of FH535 and a novel derivative Y3, on proliferation, mitochondrial function and cellular metabolism focusing on the three key substrates, glutamine, glucose, and fatty acids. RESULTS: FH535 and Y3 disrupted mitochondrial redox control in HCC cells that resulted from uncoupling mechanisms that increased proton leakage and decreased ATP production leading to apoptosis. The uncoupling effects of the sulfonamides in HCC cells were supported by the loss of activity of the methylated analogs. The accumulation of ROS significantly contributed to cell damage after the impaired autophagic machinery. These sulfonamides, FH535 and Y3, targeted glutamine and fatty acid metabolism and caused HCC cell reprograming towards the preferential use of glucose and the glycolytic pathway. CONCLUSIONS: FH535, and Y3, demonstrated potent anti-HCC activity by targeting OXPHOS, increasing dangerous levels of ROS and reducing ATP production. These sulfonamides target glutamine and FA metabolic pathways significantly increasing the cellular dependency on glycolysis.

Autophagic flux modulation by Wnt/ß-catenin pathway inhibition in hepatocellular carcinoma.

Autophagy targets cellular components for lysosomal-dependent degradation in which the products of degradation may be recycled for protein synthesis and utilized for energy production. Autophagy also plays a critical role in cell homeostasis and the regulation of many physiological and pathological processes and prompts this investigation of new agents to effect abnormal autophagy in hepatocellular carcinoma (HCC). 2,5-Dichloro-N-(2-methyl-4-nitrophenyl) benzenesulfonamide (FH535) is a synthetic inhibitor of the Wnt/ß-catenin pathway that exhibits anti-proliferative and anti-angiogenic effects on different types of cancer cells. The combination of FH535 with sorafenib promotes a synergistic inhibition of HCC and liver cancer stem cell proliferation, mediated in part by the simultaneous disruption of mitochondrial respiration and glycolysis. We demonstrated that FH535 decreased HCC tumor progression in a mouse xenograft model. For the first time, we showed the inhibitory effect of an FH535 derivative, FH535-N, alone and in combination with sorafenib on HCC cell proliferation. Our study revealed the contributing effect of Wnt/ß-catenin pathway inhibition by FH535 and its derivative (FH535-N) through disruption of the autophagic flux in HCC cells.

Effect of critical care complications on perioperative mortality and hospital length of stay after hepatectomy: A multicenter analysis of 21,443 patients.

OBJECTIVE: To determine predictors of critical care complications (CCC) in patients undergoing hepatectomy. METHODS: All hepatectomy patients in NSQIP from 2012 to 2016 were analyzed. CCC included prolonged ventilation (>48 h), sepsis/septic shock, renal failure/insufficiency, cardiac arrest/AMI and pulmonary embolism. RESULTS: A total of 21,443 patients underwent hepatectomy during the study period. Overall rate of CCC was 11%, with the most common being sepsis/septic shock (6.1%) and respiratory failure (4.9%). On multivariate analysis the preoperative risk factors associated with CCC included ASA Class IV-V (OR:2.04, p < 0.0001), diabetes (OR = 1.28, p = 0.0001), pre-operative ventilator use (OR: 17.75, p = 0.0003); COPD (OR: 1.65, p < 0.0001); pre-operative weight loss >10% (OR: 1.35, p = 0.0026); pre-operative sepsis (OR: 2.14, p < 0.0001). Propensity score matched analysis demonstrated a significant increased risk of mortality in patients with CCC (OR: 26.75, p < 0.0001) and a prolonged LOS of 10.5 days above the mean (ß Estimate: 10.51, p < 0.0001). CONCLUSIONS: ASA class, diabetes, COPD, pre-operative weight loss >10% and pre-operative sepsis are the strongest predictors of CCC after hepatectomy. The presence of CCC significantly increased the risk of peri-operative mortality 26-fold.

mTOR Inhibitor Everolimus in Regulatory T Cell Expansion for Clinical Application in Transplantation.

BACKGROUND: Experimental and preclinical evidence suggest that adoptive transfer of regulatory T (Treg) cells could be an appropriate therapeutic strategy to induce tolerance and improve graft survival in transplanted patients. The University of Kentucky Transplant Service Line is developing a novel phase I/II clinical trial with ex vivo expanded autologous Treg cells as an adoptive cellular therapy in renal transplant recipients who are using everolimus (EVR)-based immunosuppressive regimen. METHODS: The aim of this study was to determine the mechanisms of action and efficacy of EVR for the development of functionally competent Treg cell-based adoptive immunotherapy in transplantation to integrate a common EVR-based regimen in vivo (in the patient) and ex vivo (in the expansion of autologous Treg cells). CD25 Treg cells were selected from leukapheresis product with a GMP-compliant cell separation system and placed in 5-day (short) or 21-day (long) culture with EVR or rapamycin (RAPA). Multi-parametric flow cytometry analyses were used to monitor the expansion rates, phenotype, autophagic flux, and suppressor function of the cells. phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway profiles of treated cells were analyzed by Western blot and cell bioenergetic parameters by extracellular flux analysis. RESULTS: EVR-treated cells showed temporary slower growth, lower metabolic rates, and reduced phosphorylation of protein kinase B compared with RAPA-treated cells. In spite of these differences, the expansion rates, phenotype, and suppressor function of long-term Treg cells in culture with EVR were similar to those with RAPA. CONCLUSIONS: Our results support the feasibility of EVR to expand functionally competent Treg cells for their clinical use.

Outcomes in patients with portal hypertension undergoing gastrointestinal surgery: A propensity score matched analysis from the NSQIP dataset.

BACKGROUND/AIM: We aim to study the impact of PH in patients undergoing gastrointestinal surgery (GI). METHODS: We queried the ACS-NSQIP database from 2005 through 2010 for patients undergoing GI surgery with PH. Esophageal varices (EV) diagnosis was used as a surrogate of PH. RESULTS: A total of 192,296 patients underwent GI surgery, of which 379 had PH. Regression analyses revealed that patients with PH had a 6-fold (95% CI 4.6-7.9) increase in 30-day mortality, a 3-fold (95% CI 2.5-3.7) increase in morbidity, a 3.2-fold (95% CI 2.6-3.9) increase in critical care complications (CCC), and a 6.5-day (95% CI 5.1-7.8) increase in hospital LOS. After PSM, the impact of PH on the outcomes remained. These differences were significant regardless of the emergent or elective status of the procedure. AUC analysis demonstrated that MELD and MELDNa + score greater than 10.5 was the most predictive of peri-operative mortality in elective PH cases. CONCLUSIONS: PH is associated with an increased risk of poor surgical outcomes in patients undergoing elective and emergent gastrointestinal surgery.

Novel biomarkers in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths and the fifth most common cancer worldwide. Most of these patients are seen with advanced disease at the time of presentation. In spite of its high prevalence, there are not many therapeutic options available for patients with advanced-stage HCC. There is an urgent need for improving early detection and prognostication of patients with HCC. In addition, the development of new therapies targeting specific pathways involved in the pathogenesis of HCC should be a major goal for future research, with the objective of improving outcomes of patients with HCC. Biomarkers represent a relatively easy and noninvasive way to detect and estimate disease prognosis. In spite of the numerous efforts to find molecules as possible biomarkers, there is not a single ideal marker in HCC. Many new findings have shown promising results both in diagnosing and treating HCC. In this review, we summarized the most recent and relevant biomarkers in HCC.

Quercetin inhibits Cr(VI)-induced malignant cell transformation by targeting miR-21-PDCD4 signaling pathway.

Hexavalent chromium [Cr(VI)] is an important human carcinogen associated with pulmonary diseases and lung cancer. Inhibition of Cr(VI)-induced carcinogenesis by a dietary antioxidant is a novel approach. Quercetin is one of the most abundant dietary flavonoids widely present in many fruits and vegetables, possesses potent antioxidant and anticancer properties. MicroRNA-21 (miR-21) is a key oncomiR significantly elevated in the majority of human cancers that exerts its oncogenic activity by targeting the tumor suppressor gene programmed cell death 4 (PDCD4). The present study examined the effect of quercetin on the inhibition of Cr(VI)-induced malignant cell transformation and the role of miR-21-PDCD4 signaling involved. Our results showed that quercetin decreased ROS generation induced by Cr(VI) exposure in BEAS-2B cells. Chronic Cr(VI) exposure induced malignant cell transformation, increased miR-21 expression and caused inhibition of PDCD4, which were significantly inhibited by the treatment of quercetin in a dose dependent manner. Nude mice injected with BEAS-2B cells chronically exposed to Cr(VI) in the presence of quercetin showed reduced tumor incidence compared to Cr(VI) alone treated group. Stable knockdown of miR-21 and overexpression of PDCD4 or catalase in BEAS-2B cells suppressed Cr(VI)-induced malignant transformation and tumorigenesis. Taken together, these results demonstrate that quercetin is able to protect BEAS-2B cells from Cr(VI)-induced carcinogenesis by targeting miR-21-PDCD4 signaling.

Evidence of the immunomodulatory role of dual PI3K/mTOR inhibitors in transplantation: an experimental study in mice.

The PI3K/mTOR signaling cascade is fundamental in T-cell activation and fate decisions. We showed the distinct regulation of PI3K/mTOR in regulatory and effector T-cells and proposed the potential therapeutic benefit of targeting this pathway to control the balance between effector and regulatory T-cell activities. Substantial adverse effects in long-term clinical usage of rapamycin suggest the use of alternative treatments in restraining effector T-cell function in transplant patients. We hypothesize that dual PI3K/mTOR inhibitors may represent an immunosuppressant alternative. Here we show that dual PI3K/mTOR PI-103 and PKI-587 inhibitors interfered IL-2-dependent responses in T-cells. However, in contrast to the inhibitory effects in non-Treg T-cell proliferation and effector functions, dual inhibitors increased the differentiation, preferential expansion, and suppressor activity of iTregs. Rapamycin, PI-103, and PKI-587 targeted different signaling events and induced different metabolic patterns in primary T-cells. Similar to rapamycin, in vivo administration of PI-103 and PKI-587 controlled effectively the immunological response against allogeneic skin graft. These results characterize specific regulatory mechanisms of dual PI3K/mTOR inhibitors in T-cells and support their potential as a novel therapeutic option in transplantation.

Sorafenib and FH535 in combination act synergistically on hepatocellular carcinoma by targeting cell bioenergetics and mitochondrial function.

Treatment of advanced hepatocellular carcinoma (HCC) remains a challenge due to the high tumor heterogeneity. In the present study, we aim to evaluate the impact of the ß-catenin inhibitor, FH535, alone or in combination with the Ras/Raf/MAPK inhibitor Sorafenib, on the bioenergetics profiles of the HCC cell lines Huh7 and PLC/PRF/5. Single low-dose treatments with FH535 or Sorafenib promoted different effects on mitochondrial respiration and glycolysis in a cell type specific manner. However, the combination of these drugs significantly reduced both mitochondrial respiration and glycolytic rates regardless of the HCC cells. The significant changes in mitochondrial respiration observed in cells treated with the Sorafenib-FH535 combination may correspond to differential targeting of ETC complexes and changes in substrate utilization mediated by each drug. Moreover, the bioenergetics changes and the loss of mitochondrial membrane potential that were evidenced by treatment of HCC cells with the combination of FH535 and Sorafenib, preceded the induction of cell apoptosis. Overall, our results demonstrated that Sorafenib-FH535 drug combination induce the disruption of the bioenergetics of HCC by the simultaneous targeting of mitochondrial respiration and glycolytic flux that leads the synergistic effect on inhibition of cell proliferation. These findings support the therapeutic potential of combinatory FH535-Sorafenib treatment of the HCC heterogeneity by the simultaneous targeting of different molecular pathways.

Hexavalent chromium induces malignant transformation of human lung bronchial epithelial cells via ROS-dependent activation of miR-21-PDCD4 signaling.

Hexavalent chromium [Cr(VI)] is a well-known human carcinogen associated with an increased risk of lung cancer. However, the mechanisms underlying Cr(VI)-induced carcinogenesis remain unclear. MicroRNA-21 (miR-21) is a key regulator of oncogenic processes. Studies have shown that miR-21 exerts its oncogenic activity by targeting the tumor suppressor gene programmed cell death 4 (PDCD4). The present study examined the role of miR-21-PDCD4 signaling in Cr(VI)-induced cell transformation and tumorigenesis. Results showed that Cr(VI) induces ROS generation in human bronchial epithelial (BEAS-2B) cells. Chronic exposure to Cr(VI) is able to cause malignant transformation in BEAS-2B cells. Cr(VI) caused a significant increase of miR-21 expression associated with an inhibition of PDCD4 expression. Notably, STAT3 transcriptional activation by IL-6 is crucial for the Cr(VI)-induced miR-21 elevation. Stable knockdown of miR-21 or overexpression of PDCD4 in BEAS-2B cells significantly reduced the Cr(VI)-induced cell transformation. Furthermore, the Cr(VI) induced inhibition of PDCD4 suppressed downstream E-cadherin protein expression, but promoted ß-catenin/TCF-dependent transcription of uPAR and c-Myc. We also found an increased miR-21 level and decreased PDCD4 expression in xenograft tumors generated with chronic Cr(VI)-exposed BEAS-2B cells. In addition, stable knockdown of miR-21 and overexpression of PDCD4 reduced the tumorogenicity of chronic Cr(VI)-exposed BEAS-2B cells in nude mice. Taken together, these results demonstrate that the miR-21-PDCD4 signaling axis plays an important role in Cr(VI)-induced carcinogenesis.

Cancer stem cell marker expression alone and in combination with microvascular invasion predicts poor prognosis in patients undergoing transplantation for hepatocellular carcinoma.

BACKGROUND: The cancer stem cell hypothesis provides an explanation for hepatocellular carcinoma (HCC) heterogeneity. We investigated the expression of CD44 and CD133 alone and in combination with microvascular invasion (MVI) as predictors of prognosis in patients undergoing liver transplantation for HCC. METHODS: Explanted livers from 95 patients transplanted for HCC were analyzed. Marker expression was evaluated by immunofluorescence. RESULTS: Seventy-seven patients were male with a mean age of 56 years. The most common etiologies of cirrhosis were hepatitis C (50%) and alcoholic liver disease (41%). Forty-one patients had laboratory model for end-stage liver disease score greater than 15. Overall survival (OS) at 1-, 3-, and 5-years was 86%, 75%, and 64%, respectively. Recurrence rate was 13% with a median follow-up of 64 months. The 5-year OS was significantly lower in those patients with MVI and CD44 (36.9%) or CD133 (40%). CD44(+) and CD133(+) correlated with increased risk of poorly differentiated HCC, and elevated alpha-fetoprotein levels. In combination with MVI, both markers were independently associated with increased recurrence and worse OS (recurrence P < .003, odds ratio = 8.05; P = .001, odds ratio = 9.5, survival P = .001, HR = 3.7; P = .004, HR = 3.2 respectively). CONCLUSIONS: CD44 or CD133 alone and in combination with MVI are independent predictors of poor prognosis in patients undergoing transplantation for HCC.

Targeting Wnt/ß-catenin pathway in hepatocellular carcinoma treatment.

Hepatocellular carcinoma (HCC) is one of the most common causes of cancer-related death worldwide. Liver cancer is generally related to hepatitis B or C infection and cirrhosis. Usually, patients with HCC are asymptomatic and are diagnosed at late stages when surgical treatment is no longer suitable. Limited treatment options for patients with advanced HCC are a major concern. Therefore, there is an urge for finding novel therapies to treat HCC. Liver cancer is highly heterogeneous and involved deregulation of several signaling pathways. Wnt/ß-catenin pathway is frequently upregulated in HCC and it is implicated in maintenance of tumor initiating cells, drug resistance, tumor progression, and metastasis. A great effort in developing selective drugs to target components of the ß-catenin pathway with anticancer activity is underway but only a few of them have reached phase I clinical trials. We aim to review the role of ß-catenin pathway on hepatocarcinogenesis and liver cancer stem cell maintenance. We also evaluated the use of small molecules targeting the Wnt/ß-catenin pathway with potential application for treatment of HCC.

N-Aryl benzenesulfonamide inhibitors of [3H]-thymidine incorporation and ß-catenin signaling in human hepatocyte-derived Huh-7 carcinoma cells.

Structure-activity relationships (SAR) in 2,5-dichloro-N-(2-methyl-4-nitrophenyl)benzenesulfonamide (FH535) were examined as part of a program to identify agents that inhibit the Wnt/ß-catenin signaling pathway that is frequently upregulated in hepatocellular carcinoma (HCC). FH535 was reported as an inhibitor of both ß-catenin in the Wnt signaling pathway and the peroxisome proliferator-activated receptor (PPAR). A ß-catenin/T-cell factor (TCF)/Lymphoid-enhancer factor (LEF)-dependent assay (i.e., luciferase-based TOPFlash assay) as well as a [(3)H]-thymidine incorporation assay were used to explore SAR modifications of FH535. Although replacing the 2,5-dichlorophenylsulfonyl substituent in FH535 with a 2,6-dihalogenation pattern generally produced more biologically active analogs than FH535, other SAR modifications led only to FH535 analogs with comparable or slightly improved activity in these two assays. The absence of a clear SAR pattern in activity suggested a multiplicity of target effectors for N-aryl benzenesulfonamides.

IS6110 in oriC affects the morphology and growth of Mycobacterium tuberculosis and attenuates virulence in mice.

The IS6110 element is widely used in studies of molecular epidemiology of tuberculosis and it is considered the gold standard for genotyping Mycobacterium tuberculosis strains. Because of its high frequency of transposition, IS6110 is probably a major contributor to the evolution of M. tuberculosis. Nevertheless, very few studies of the effect of IS6110 insertions on the virulence of M. tuberculosis have been reported. We analysed two isogenic groups of M. tuberculosis strains isolated from the sputa of two patients. Strains belonging to the same isogenic group differed from one another by one IS6110-oriC hybridising band, but they showed identical spoligo and MIRU-VNTR profiles. Isogenic strains containing the IS6110 element in oriC exhibited a diminished growth rate and average dimensions of the bacilli were modified; moreover, they were less virulent in a mouse model.

The role of MAPKs in B cell receptor-induced down-regulation of Egr-1 in immature B lymphoma cells.

Cross-linking of the B cell receptor (BCR) on the immature B lymphoma cell line BKS-2 induces growth inhibition and apoptosis accompanied by rapid down-regulation of the immediate-early gene egr-1. In these lymphoma cells, egr-1 is expressed constitutively and has a prosurvival role, as Egr-1-specific antisense oligonucleotides or expression of a dominant-negative inhibitor of Egr-1 also prevented the growth of BKS-2 cells. Moreover, enhancement of Egr-1 protein with phorbol 12-myristate 13-acetate or an egr-1 expression vector rescued BKS-2 cells from BCR signal-induced growth inhibition. Nuclear run-on and mRNA stability assays indicated that BCR-derived signals act at the transcriptional level to reduce egr-1 expression. Inhibitors of ERK and JNK (but not of p38 MAPK) reduced egr-1 expression at the protein level. Transcriptional regulation appears to have a role because egr-1 promoter-driven luciferase expression was reduced by ERK and JNK inhibitors. Promoter truncation experiments suggested that several serum response elements are required for MAPK-mediated egr-1 expression. Our study suggests that BCR signals reduce egr-1 expression by inhibiting activation of ERK and JNK. Unlike ERK and JNK, p38 MAPK reduces constitutive expression of egr-1. Unlike the immature B lymphoma cells, normal immature B cells did not exhibit constitutive MAPK activation. BCR-induced MAPK activation was modest and transient with a small increase in egr-1 expression in normal immature B cells consistent with their inability to proliferate in response to BCR cross-linking.

Transcription analysis of the dnaA gene and oriC region of the chromosome of Mycobacterium smegmatis and Mycobacterium bovis BCG, and its regulation by the DnaA protein.

The regions flanking the Mycobacterium dnaA gene have extensive sequence conservation, and comprise various DnaA boxes. Comparative analysis of the dnaA promoter and oriC region from several mycobacterial species revealed that the localization, spacing and orientation of the DnaA boxes are conserved. Detailed transcriptional analysis in M. smegmatis and M. bovis BCG shows that the dnaN gene of both species and the dnaA gene of M. bovis BCG are transcribed from two promoters, whereas the dnaA gene of M. smegmatis is transcribed from a single promoter. RT-PCR with total RNA showed that dnaA and dnaN were expressed in both species at all growth stages. Analysis of the promoter activity using dnaA-gfp fusion plasmids and DnaA expression plasmids indicates that the dnaA gene is autoregulated, although the degree of transcriptional autorepression was moderate. Transcription was also detected in the vicinity of oriC of M. bovis BCG, but not of M. smegmatis. These results suggest that a more complex transcriptional mechanism may be involved in the slow-growing mycobacteria, which regulates the expression of dnaA and initiation of chromosomal DNA replication.