Cyclooxygenases in hepatocellular carcinoma

From viruses to cancer: exploring the role of the hepatitis C virus NS3 protein in carcinogenesis

Hepatitis C virus (HCV) chronically infects approximately 170 million people worldwide and is a known etiological agent of hepatocellular carcinoma (HCC). The molecular mechanisms of HCV-mediated carcinogenesis are not fully understood. This review article focuses on the oncogenic potential of NS3, a viral protein with transformative effects on cells, although the precise mechanisms remain elusive. Unlike the more extensively studied Core and NS5A proteins, NS3's roles in cancer development are less defined but critical. Research indicates that NS3 is implicated in several carcinogenic processes such as proliferative signaling, cell death resistance, genomic instability and mutations, invasion and metastasis, tumor-related inflammation, immune evasion, and replicative immortality. Understanding the direct impact of viral proteins such as NS3 on cellular transformation is crucial for elucidating HCV's role in HCC development. Overall, this review sheds light on the molecular mechanisms used by NS3 to contribute to hepatocarcinogenesis, and highlights its significance in the context of HCV-associated HCC, underscoring the need for further investigation into its specific molecular and cellular actions.

Diet, lifestyle factors, comorbidities, and hepatocellular carcinoma risk in a middle eastern country: a case-control study

BACKGROUND

Hepatocellular Carcinoma (HCC) can be classified as one of the most common malignancies worldwide. There is scarcity of the published data on the risk factors for HCC in the Gulf Cooperation Council countries specifically Kuwait. Therefore, this case-control study sought to examine the risk factors associated with HCC in Kuwait.

METHODS

Fifty-three histopathologically confirmed HCC cases were recruited from the Kuwait Cancer Control Center Registry. One hundred ninety-six controls (1:4 ratio) were selected from medical and/ or surgical outpatient's clinics at all six public hospitals of Kuwait. A structured questionnaire was used to collect the data both from cases and controls through face-to-face interviews. A multivariable logistic regression model was fitted to the case-control data. Adjusted odds ratios (ORadj) and their 95% confidence intervals (CI) were computed using the parameters' estimates of the final model and used for interpretation of the model.

RESULTS

The HCC cases compared with the controls were 41.6 times more likely to have had the history of non-alcoholic fatty liver disease (NAFLD) (ORadj = 41.6; 95% CI: 8.9-193.5; p < 0.001). The cases compared with the controls were more likely to have reported the history of heavy alcohol drinking (ORadj = 14.2; 95% CI: 1.2-173.4; p = 0.038). Furthermore, compared with the controls, the HCC cases tended to frequently consume milk and/or milk substitutes (≥ 3 glass/ week) (ORadj = 7.2; 95% CI: 1.2-43.4). Conversely however, there was a significant protective effect if the participants reportedly have had regularly used olive oil in their routine diet as a source of fat (ORadj = 0.17; 95% CI: 0.04-0.80) or regularly used non-steroid anti-inflammatory drugs (NSAIDs) (ORadj = 0.20; 95% CI: 0.05-0.71).

CONCLUSIONS

This study showed that heavy alcohol consumption, NAFLD history, and excessive consumption of milk/ milk substitutes were associated with a significantly increased HCC risk. Conversely however, regular use of olive oil in the diet as a source of fat or regular use of NSAIDs had a significantly protective effect against HCC risk. Adapting healthy dietary habits and preventing/ treating NAFLD may minimize the HCC risk. Future research with a larger sample size may contemplate validating the results of this study and unraveling additional risk factors contributing to HCC risk. The resultant data may help design and implement evidence-based educational programs for the prevention of HCC in this and other similar settings.

A novel black poplar propolis extract with promising health-promoting properties: focus on its chemical composition, antioxidant, anti-inflammatory, and anti-genotoxic activities

Propolis is a resinous mixture produced by honeybees which has been used since ancient times for its useful properties. However, its chemical composition and bioactivity may vary, depending on the geographical area of origin and the type of tree bees use for collecting pollen. In this context, this research aimed to investigate the total phenolic content (using the Folin-Ciocalteu assay) and the total antioxidant capacity (using the FRAP, DPPH, and ABTS assays) of three black poplar (Populus nigra L.) propolis (BPP) solutions (S1, S2, and S3), as well as the chemical composition (HPLC-ESI-MSn) and biological activities (effect on cell viability, genotoxic/antigenotoxic properties, and anti-inflammatory activity, and effect on ROS production) of the one which showed the highest antioxidant activity (S1). The hydroalcoholic BPP solution S1 was a prototype of an innovative, research-type product by an Italian nutraceutical manufacturer. In contrast, hydroalcoholic BPP solutions S2 and S3 were conventional products purchased from local pharmacy stores. For the three extracts, 50 phenolic compounds, encompassing phenolic acids and flavonoids, were identified. In summary, the results showed an interesting chemical profile and the remarkable antioxidant, antigenotoxic, anti-inflammatory and ROS-modulating activities of the innovative BPP extract S1, paving the way for future research. In vivo investigations will be a possible line to take, which may help corroborate the hypothesis of the potential health benefits of this product, and even stimulate further ameliorations of the new prototype.

In silico screening, synthesis, characterization and biological evaluation of novel anticancer agents as potential COX-2 inhibitors

BACKGROUND

Cyclooxygenase enzyme is frequently overexpressed in various types of cancer and found to play a crucial role in poor prognosis in cancer patients. In current research, we have reported the new COX-2 inhibitors for cancer treatment using computer-aided drug design and experimental validation.

METHODS

A total of 12,795 compounds from the different databases were used to screen against the COX-2 enzyme. It perceived three new compounds with better binding affinity to the enzyme. Afterwards, physicochemical properties and in silico bioactivity were assessed for efficacy, safety, and structural features required for binding. The molecules were synthesized and confirmed by spectroscopic techniques. Later on, molecules were evaluated for their anti-cancer activity using MCF-7, MDA-MB-231 and SiHa cancer cell lines.

RESULTS

Compound ZINC5921547 and ZINC48442590 (4a, and 4b) reduced the MCF-7, MDA-MB-231, and SiHa cells proliferation potently than parent compounds. The PG-E2 estimation shown, both compounds act through the COX-2 PGE2 axis. Compound 4a and 4b block the cell cycle at G1-S phase and induce cancer cell death.

CONCLUSIONS

We concluded that compounds 4a and 4b effectively promotes cancer cell death via COX-2 PGE2 axis, and further in vivo studies can be evaluated for development in both compounds as anticancer agents. The compilation of this information will help us to generate better outcome through robust computational methods. The high-quality experimental results may pave the way for identifying effective drug candidates for cancer treatment.

C-Reactive Protein Signaling Pathways in Tumor Progression

Many cancers arise from sites of chronic inflammation, which creates an inflammatory microenvironment surrounding the tumor. Inflammatory substances secreted by cells in the inflammatory environment can induce the proliferation and survival of cancer cells, thereby promoting cancer metastasis and angiogenesis. Therefore, it is important to identify the role of inflammatory factors in cancer progression. This review summarizes the signaling pathways and roles of C-reactive protein (CRP) in various cancer types, including breast, liver, renal, and pancreatic cancer, and the tumor microenvironment. Mounting evidence suggests the role of CRP in breast cancer, particularly in triple-negative breast cancer (TNBC), which is typically associated with a worse prognosis. Increased CRP in the inflammatory environment contributes to enhanced invasiveness and tumor formation in TNBC cells. CRP promotes endothelial cell formation and angiogenesis and contributes to the initiation and progression of atherosclerosis. In pancreatic and kidney cancers, CRP contributes to tumor progression. In liver cancer, CRP regulates inflammatory responses and lipid metabolism. CRP modulates the activity of various signaling molecules in macrophages and monocytes present in the tumor microenvironment, contributing to tumor development, the immune response, and inflammation. In the present review, we overviewed the role of CRP signaling pathways and the association between inflammation and cancer in various types of cancer. Identifying the interactions between CRP signaling pathways and other inflammatory mediators in cancer progression is crucial for understanding the complex relationship between inflammation and cancer.

Unlocking the Potential: Novel NSAIDs Hybrids Unleash Chemopreventive Power toward Liver Cancer Cells through Nrf2, NF-κB, and MAPK Signaling Pathways

HCC is a highly aggressive malignancy with limited treatment options. In this study, novel conjugates of non-steroidal anti-inflammatory drugs (NSAIDs)-Ibuprofen and Ketoprofen-with oleanolic acid oximes derivatives (OAO) were synthesized, and their activity as modulators of signaling pathways involved in HCC pathogenesis was evaluated in normal THLE-2 liver cells, and HCC-derived HepG2 cells. The results demonstrated that conjugation with OAO derivatives reduces the cytotoxicity of parent compounds in both cell lines. In THLE-2 cells, treatment with conjugates resulted in increased activation of the Nrf2-ARE pathway. An opposite effect was observed in HepG2 cells. In the later reduction of NF-κB, it was observed along with modulation of MAPK signaling pathways (AKT, ERK, p38, p70S6K, and JNK). Moreover, STAT3, STAT5, and CREB transcription factors on protein levels were significantly reduced as a result of treatment with IBU- and KET-OAO derivatives conjugates. The most active were conjugates with OAO-morpholide. Overall, the findings of this study demonstrate that IBU-OAO and KET-OAO derivative conjugates modulate the key signaling pathways involved in hepatic cancer development. Their effect on specific signaling pathways varied depending on the structure of the conjugate. Since the conjugation of IBU and KET with OAO derivatives reduced their cytotoxicity, the conjugates may be considered good candidates for the prevention of liver cancer.

The Effect of Aspirin Use on Incident Hepatocellular Carcinoma-An Updated Systematic Review and Meta-Analysis

An increasing number of observational studies have described an association between aspirin use and a reduced risk of incident hepatocellular carcinoma. We performed this meta-analysis to provide a comprehensive and updated aggregate assessment of the effect of aspirin on HCC incidence. Two independent authors performed a systematic search of the literature, utilising the Medline, Embase, Scopus, and PubMed databases. A total of 16 studies (12 cohort studies, and 4 case-control studies) were selected for inclusion, with a large number of studies excluded, due to an overlapping study population. The pooled analysis of cohort studies involving a total population of approximately 2.5 million subjects, 822,680 aspirin users, and 20,626 HCC cases demonstrated a 30% reduced risk of HCC associated with aspirin use (adjusted HR 0.70, 95%CI 0.60-0.81). There was a similar but non-significant association observed across the case-control studies (adjusted OR 0.60, 95%CI 0.32-1.15, p = 0.13), which involved a total of 1961 HCC cases. In a subgroup meta-analysis of patients with cirrhosis, the relationship between aspirin use and incident HCC diminished to non-significance (adjusted HR 0.96, 95%CI 0.84-1.09). Aspirin use was associated with a statistically significant increase in bleeding events when all relevant studies were pooled together (adjusted HR 1.11, 95%CI 1.02-1.22). Prospectively collected data should be sought, to define the optimal patient group in which aspirin is safe and effective for the chemoprophylaxis of HCC.

Chemotherapeutic Drug-Regulated Cytokines Might Influence Therapeutic Efficacy in HCC

Hepatocellular carcinoma (HCC), the most common type of liver cancer, is the second leading cause of cancer-related mortality worldwide. Processes involved in HCC progression and development, including cell transformation, proliferation, metastasis, and angiogenesis, are inflammation-associated carcinogenic processes because most cases of HCC develop from chronic liver damage and inflammation. Inflammation has been demonstrated to be a crucial factor inducing tumor development in various cancers, including HCC. Cytokines play critical roles in inflammation to accelerate tumor invasion and metastasis by mediating the migration of immune cells into damaged tissues in response to proinflammatory stimuli. Currently, surgical resection followed by chemotherapy is the most common curative therapeutic regimen for HCC. However, after chemotherapy, drug resistance is clearly observed, and cytokine secretion is dysregulated. Various chemotherapeutic agents, including cisplatin, etoposide, and 5-fluorouracil, demonstrate even lower efficacy in HCC than in other cancers. Tumor resistance to chemotherapeutic drugs is the key limitation of curative treatment and is responsible for treatment failure and recurrence, thus limiting the ability to treat patients with advanced HCC. Therefore, the capability to counteract drug resistance would be a major clinical advancement. In this review, we provide an overview of links between chemotherapeutic agents and inflammatory cytokine secretion in HCC. These links might provide insight into overcoming inflammatory reactions and cytokine secretion, ultimately counteracting chemotherapeutic resistance.

A Systematic Review of the Cyclooxygenase-2 (COX-2) Expression in Rectal Cancer Patients Treated with Preoperative Radiotherapy or Radiochemotherapy

The main objective of this systematic review is to investigate the expression level of the cyclooxygenase-2 (COX-2) in rectal cancer treated with either preoperative radiotherapy or radiochemotherapy. In addition, we have summarized the effects of preoperative treatment of rectal cancer with regards to the expression levels of COX-2. A systematic literature review was performed in The Cochrane Library, PubMed, Web of Science, and Scopus databases on 1 January 2021 with the usage of the following search string-(cyclooxygenase-2) OR (COX-2) AND (rectal cancer) AND (preoperative radiochemotherapy) OR (preoperative radiotherapy). Among the 176 included in the analysis, only 13 studies were included for data extraction with a total number of 2095 patients. The results of the analysis are based on the articles concerning the expression of COX-2 in rectal cancer among patients treated with preoperative radiotherapy or radiochemotherapy. A COX-2 expression is an early event involved in rectal cancer development. In cases of negative COX-2 expression, radiotherapy and radiochemotherapy might contribute to the reduction of a local recurrence. Therefore, COX-2 may be considered as a biologic factor while selecting patients for more effective, less time-consuming and less expensive preoperative treatment. However, the utility of the administration of COX-2 inhibitors to patients with COX-2 overexpression, in an attempt to improve the patients' response rate to the neoadjuvant treatment, needs an assessment in further clinical trials.

Conjugation of Diclofenac with Novel Oleanolic Acid Derivatives Modulate Nrf2 and NF-κB Activity in Hepatic Cancer Cells and Normal Hepatocytes Leading to Enhancement of Its Therapeutic and Chemopreventive Potential

Combining NSAIDs with conventional therapeutics was recently explored as a new strategy in cancer therapy. Our earlier studies showed that novel oleanolic acid oximes (OAO) conjugated with aspirin or indomethacin may enhance their anti-cancer potential through modulation of the Nrf2 and NF-κB signaling pathways. This study focused on the synthesis and biological evaluation of four diclofenac (DCL)–OAO derivative conjugates in the context of these pathways’ modification and hepatic cells survival. Treatment with the conjugates 4d, 3-diclofenacoxyiminoolean-12-en-28-oic acid morpholide, and 4c, 3-diclofenacoxyiminoolean-12-en-28-oic acid benzyl ester significantly reduced cell viability in comparison to the DCL alone. In THLE-2, immortalized normal hepatocytes treated with these conjugates resulted in the activation of Nrf2 and increased expression in SOD-1 and NQO1, while the opposite effect was observed in the HepG2 hepatoma cells. In both cell lines, reduced activation of the NF-κB and COX-2 expression was observed. In HepG2 cells, conjugates increased ROS production resulting from a reduced antioxidant defense, induced apoptosis, and inhibited cell proliferation. In addition, the OAO morpholide derivative and its DCL hybrid reduced the tumor volume in mice bearing xenografts. In conclusion, our study demonstrated that conjugating diclofenac with the OAO morpholide and a benzyl ester might enhance its anti-cancer activity in HCC.

Cysteine Aminotransferase (CAT): A Pivotal Sponsor in Metabolic Remodeling and an Ally of 3-Mercaptopyruvate Sulfurtransferase (MST) in Cancer

Metabolic remodeling is a critical skill of malignant cells, allowing their survival and spread. The metabolic dynamics and adaptation capacity of cancer cells allow them to escape from damaging stimuli, including breakage or cross-links in DNA strands and increased reactive oxygen species (ROS) levels, promoting resistance to currently available therapies, such as alkylating or oxidative agents. Therefore, it is essential to understand how metabolic pathways and the corresponding enzymatic systems can impact on tumor behavior. Cysteine aminotransferase (CAT) per se, as well as a component of the CAT: 3-mercaptopyruvate sulfurtransferase (MST) axis, is pivotal for this metabolic rewiring, constituting a central mechanism in amino acid metabolism and fulfilling the metabolic needs of cancer cells, thereby supplying other different pathways. In this review, we explore the current state-of-art on CAT function and its role on cancer cell metabolic rewiring as MST partner, and its relevance in cancer cells' fitness.

A Modified Protocol of Diethylnitrosamine Administration in Mice to Model Hepatocellular Carcinoma

We aimed to create an animal model for hepatocellular carcinoma (HCC) with a short time, a high survival rate, as well as a high incidence of HCC in both males and females than previously reported. The Diethylnitrosamine (DEN) model has an age-related effect. A single dose of DEN treatment is not enough in young mice up to 50 weeks. The same pattern is shown in an adult with multiple-dose trials whether or not there is some promotion agent. In this study, two-week old C57BL6 mice were given a total of eight doses of DEN, initially 20mg/kg body weight, and then 30mg/kg in the third week, followed by 50mg/kg for the last six weeks. The first group is DEN treatment only and the other two groups received thioacetamide (TAA) treatment for four or eight weeks after one week of rest from the last DEN treatment. An autopsy was performed after 24 weeks of the initial dose of DEN in each group. The cellular arrangement of HCC in the entire group was well-differentiated carcinoma and tumor presence with no significant impact on the survival of mice. Increased levels of the biochemical markers in serum, loss of tissue architecture, hepatocyte death, and proliferation were highly activated in all tumor-induced groups. This finding demonstrates an improved strategy to generate an animal model with a high occurrence of tumors combined with cirrhosis in a short time regardless of sex for researchers who want to investigate liver cancer-related.

Exposure to growth hormone is associated with hepatic up-regulation of cPLA2α and COX

Continuously elevated levels of growth hormone (GH) during life in mice are associated with hepatomegaly due to hepatocytes hypertrophy and hyperplasia, chronic liver inflammation, elevated levels of arachidonic acid (AA) at young ages and liver tumors development at old ages. In this work, the hepatic expression of enzymes involved in AA metabolism, cPLA2α, COX1 and COX2 enzymes, was evaluated in young and old GH-transgenic mice. Mice overexpressing GH exhibited higher hepatic expression of cPLA2α, COX1 and COX2 in comparison to controls at young and old ages and in both sexes. In old mice, when tumoral and non-tumoral tissue were compared, elevated expression of COX2 was observed in tumors. In contrast, exposure to continuous lower levels of hormone for a short period affected COX1 expression only in males. Considering the role of inflammation during liver tumorigenesis, these findings support a role of alterations in AA metabolism in GH-driven liver tumorigenesis.

Inflammatory Mechanisms of HCC Development

HCC (hepatocellular carcinoma) is the second leading cause of cancer deaths worldwide, with several etiologic causes, mostly inflammation-associated. Different inflammatory responses in the liver can be triggered by different etiological agents. The inflammatory process can be resolved or be persistent, depending on the etiology and multiple other factors. Chronic inflammation, tissue remodeling, genetic alterations, and modifications in cellular signaling are considered to be key processes promoting immunosuppression. The progressive immunosuppression leads to the inactivation of anti-tumor immunity involved in HCC carcinogenesis and progression. Tumor cellular processes including DNA damage, necrosis, and ER (endoplasmic reticulum) stress can affect both immune-surveillance and cancer-promoting inflammation, supporting a mutual interdependence. Here, we review the current understanding of how chronic liver injury and inflammation is triggered and sustained, and how inflammation is linked to HCC. The identification of many hepatic microenvironmental inflammatory processes and their effector molecules, has resulted in extensive translational work and promising clinical trials of new immunomodulatory agents.

The Carcinogenic Agent Diethylnitrosamine Induces Early Oxidative Stress, Inflammation and Proliferation in Rat Liver, Stomach and Colon: Protective Effect of Ginger Extract

Background: Diethylnitrosamine (DENA), a well-known dietary carcinogen, related to cancer initiation of various organs. The present study investigated the deleterious mechanisms involved in the early destructive changes of DENA in different organs namely, liver, stomach and colon and the potential protective effect of GE against these mechanisms. Methods: Adult male albino rats were assigned into four groups. A normal control group received the vehicle, another group was injected with a single necrogenic dose of DENA (200 mg/kg, i.p) on day 21. Two groups received oral GE (108 or 216 mg/kg) daily for 28 days. Sera, liver, stomach and colon were obtained 7 days after DENA injection. Serum aspartate transaminase and alanine transaminase were detected as well as reduced glutathione (GSH), malondialdehyde, nitric oxide metabolites, interleukin 1β, tumor necrosis factor (TNF-α), alpha-fetoprotein (AFP) and nuclear factorerythroid 2-related factor2 (Nrf2) in liver, stomach and colon. Histopathological studies and immunohistochemical examination of cyclooxygenase-2 (COX2) were conducted. Results: DENA induced elevation in liver function enzymes with significant increase in oxidation and inflammation biomarkers and AFP while decreased levels of Nrf2 in liver, stomach and colon were detected. Histologically, DENA showed degenerative changes in hepatocytes and inflammatory foci. Inflammatory foci displayed increased expression of COX2 in immunohistochemical staining. GE-pretreatment improved liver function and restored normal GSH with significant mitigation of oxidative stress and inflammatory biomarkers compared to DENA-treated group. AFP was reduced by GE in both doses, while Nrf2 increased significantly. Histology and immunostaining of hepatic COX-2 were remarkably improved in GE-treated groups in a dose dependent manner. Conclusion: GE exerted a potential anti-proliferative activity against DENA in liver, stomach and colon via Nrf2 activation, whilst suppression of oxidation and inflammation.

Saikosaponin-d Suppresses COX2 Through p-STAT3/C/EBPβ Signaling Pathway in Liver Cancer: A Novel Mechanism of Action

Saikosaponin-d (SSd) is an active extract from Radix Bupleuri, the dried root from the plant Bupleurum falcatum used in China for thousands of years to treat liver diseases. The SSd extract possesses valuable pharmacological activities including anti-cancer and anti-inflammatory effects; however, the mechanism underlying the anti-cancer activity of SSd is largely unknown. Here, we explored the mechanism of action of SSd as an anti-cancer agent for liver cancer in two human hepatocellular carcinoma cell lines. Using MTT and annexin-V-FITC/PI assays, Western blots, immunohistochemistry, qRT-PCR, luciferase reporter assay, and a JAK2-specific inhibitor (AG490), we demonstrated that the anti-tumorigenic effects of SSd act through the intermediatory p-STAT3/C/EBPβ signaling pathway to suppress cyclooxygenase (COX)-2. SSd effectively inhibited cell proliferation in a dose-dependent manner. Apoptosis was significantly increased in cells treated with SSd (2.5–15 µg/ml) with concurrent increase and decrease in pro- and anti-apoptosis proteins, respectively. COX-2, C/EBPβ, and p-STAT3 were significantly decreased, at both the translational and transcriptional levels, by SSd treatment. AG490 produced similar inhibitory effects on STAT3, p-STAT3, C/EBPβ, and COX-2. In conclusion, our data suggest that SSd controls liver cancer proliferation through suppression of the p-STAT3/C/EBPβ signaling pathway inhibiting COX2 expression. These findings further our understanding of the pharmacological action of SSd, providing new information on SSd mechanism of action and showing potential for SSd as a novel therapy for liver cancer.

Melatonin maximizes the therapeutic potential of non-preconditioned MSCs in a DEN-induced rat model of HCC

Pretreatment of mesenchymal stem cells (MSCs) with melatonin (Mel) improves their potential therapeutic effect on chronic diseases and cancers. However, this preconditioning strategy may direct the effect of Mel toward MSCs alone and deprive cancer cells of the oncostatic effect of Mel. Herein, we hypothesized that Mel given before transplantation of non-preconditioned MSCs may maximize the therapeutic outcome via the oncostatic effect of Mel by preparing a suitable tumor microenvironment for MSCs. Female rats (n = 60) were equally divided into 6 groups; normal control, diethylnitrosamine (DEN), DEN + Mel, DEN + MSCs, DEN + MSCs preconditioned with Mel, and DEN + MSCs + Mel. The obtained data revealed that administration of Mel before MSCs treatment without preconditioning yielded a better ameliorative effect against DEN-induced hepatocellular carcinoma (HCC) as evidenced by: 1) reduced serum levels of alpha fetoprotein and gamma-glutamyl transferase; 2) decreased number and area of glutathione S-transferase placental positive foci; 3) induced apoptosis (as indicated by increased cleaved caspase-3 activity, upregulated expression of proapoptotic genes Bax and caspase 3 and downregulated expression of anti-apoptotic genes Bcl2, survivin); 4) decreased malondialdehyde level and increased activities of superoxide dismutase, catalase, and glutathione peroxidase enzymes; and 5) reduced inflammation, angiogenesis and metastasis as indicated by downregulated expression of interleukin 1 beta, nuclear factor kappa B, vascular endothelial growth factor, and matrix metallopeptidase 9 genes and upregulated expression of metalloproteinase inhibitor 1 gene. Thus, administration of Mel before MSCs (without preconditioning) fostered the survival and therapeutic potential of MSCs in HCC, possibly through induction of apoptosis and inhibition of inflammation and oxidative stress. This new strategy showed better therapeutic outcomes and may improve MSC-based therapies for HCC.

lncRNA HOTAIR upregulates COX-2 expression to promote invasion and migration of nasopharyngeal carcinoma by interacting with miR-101

BACKGROUND

Nasopharyngeal carcinoma (NPC) is the most common type of head and neck cancers which is notable for its distinctive pattern of geographical distribution. HOTAIR has been reported to regulate nasopharyngeal carcinoma tumorigenesis and progression. However, the detailed mechanism underlying HOTAIR-promoted nasopharyngeal carcinoma remains not fully understood.

METHODS

We used RT-qPCR approach to examine genes expression and mRNA level. MTT assay and soft agar assay were used to detect cell growth rate in culture and under suspended condition, respectively. Besides, we employed wound healing assay and transwell invasion assay to determine migration and invasion ability of nasopharyngeal carcinoma cells. We predicted direct downstream targets of miR-101 by bioinformatic analysis, which was confirmed by dual luciferase reporter assay.

RESULTS

HOTAIR was upregulated in NPC tissues and cells. miR-101 inhibitor greatly enhanced HOTAIR knockdown-regulated cell proliferation, migration and invasion of CNE1 and CNE2 cells. miR-101 was shown to directly bind 3'-UTR of COX-2 and downregulate COX-2 expression. Finally, COX-2 overexpression was demonstrated to rescue the tumor phenotypes of nasopharyngeal carcinoma cells attenuated by HOTAIR knockdown or miR-101 mimic.

CONCLUSIONS

Here, we highlight the importance of HOTAIR/miR-101/COX-2 axis in progression of nasopharyngeal carcinoma cells. Our findings provide a novel mechanism for explaining HOTAIR-induced nasopharyngeal carcinoma and help developing the therapeutical strategies by targeting HOTAIR.

Over-activation of AKT signaling leading to 5-Fluorouracil resistance in SNU-C5/5-FU cells

Here, we investigated whether over-activation of AKT pathway is important in the resistance to 5-fluorouracil (5-FU) in SNU-C5/5-FU cells, 5-FU-resistant human colon cancer cells. When compared to wild type SNU-C5 cells (WT), SNU-C5/5-FU cells showed over-activation of PI3K/AKT pathway, like increased phosphorylation of AKT, mTOR, and GSK-3β, nuclear localization of β-catenin, and decreased E-cadherin. Moreover, E-cadherin level was down-regulated in recurrent colon cancer tissues compared to primary colon cancer tissues. Gene silencing of AKT1 or treatment of LY294002 (PI3 kinase inhibitor) increased E-cadherin, whereas decreased phospho-GSK-3β. LY294002 also reduced protein level of β-catenin with no influence on mRNA level. PTEN level was higher in SNU-C5/WT than SNU-C5/5-FU cells, whereas the loss of PETN in SNU-C5/WT cells induced characteristics of SNU-C5/5-FU cells. In SNU-C5/5-FU cells, NF-κB signaling was activated, along with the overexpression of COX-2 and stabilization of survivin. However, increased COX-2 contributed to the stabilization of survivin, which directly interacts with cytoplasmic procaspase-3, while the inhibition of AKT reduced this cascade. We finally confirmed that combination treatment with 5-FU and LY294002 or Vioxx could induce apoptosis in SNU-C5/5-FU cells. These data suggest that inhibition of AKT activation may overcome 5-FU-resistance in SNU-C5/5-FU cells. These findings provide evidence that over-activation of AKT is crucial for the acquisition of resistance to anticancer drugs and AKT pathway could be a therapeutic target for cancer treatment.

Nonsteroidal anti-inflammatory drugs, especially aspirin, are linked to lower risk and better survival of hepatocellular carcinoma: a meta-analysis

OBJECTIVE

The roles of nonsteroidal anti-inflammatory drugs (NSAIDs) in the occurrence and prognosis of hepatocellular carcinoma (HCC) remain controversial. This analysis aimed to summarize the relationships between NSAIDs and HCC development.

METHODS

Studies published prior to October 1, 2017, in the PubMed, Embase, Ovid, Web of Science, and Cochrane Library databases were systematically searched and analyzed.

RESULTS

Eleven studies were included in this analysis. A meta-analysis of five studies revealed that aspirin use could significantly decrease the risk of HCC occurrence (hazards ratio [HR] = 0.64, 95% confidence interval [CI] = 0.45-0.91, P = 0.014). No significant difference was found for the use of NSAIDs (six studies) and non-aspirin NSAIDs (three studies) in HCC occurrence (HR = 0.74, 95%CI = 0.53-1.02, P = 0.064 and HR = 0.98, 95%CI = 0.87-1.12, P = 0.81, respectively). However, subgroup analysis of cohort studies demonstrated that NSAIDs significantly decreased the risk of HCC occurrence (HR = 0.58, 95%CI = 0.43-0.78, P < 0.001). HCC patients who received NSAIDs achieved better disease-free survival and overall survival compared with the non-NSAID users (HR = 0.79, 95%CI = 0.74-0.84, P<0.001 and HR = 0.60, 95%CI = 0.50-0.72, P<0.001, respectively). Additionally, a meta-analysis of two studies showed that aspirin treatment in HCC patients could significantly decrease the 2-year and 4-year mortalities (rate ratio [RR] = 0.50, 95%CI = 0.36-0.69, P < 0.001 and RR = 0.67, 95%CI = 0.45-0.998, P = 0.049, respectively). A meta-analysis of two studies showed that aspirin use was not associated with a higher risk of bleeding in HCC patients (HR = 0.71, 95%CI = 0.41-1.23, P = 0.223).

CONCLUSION

The use of NSAIDs, especially aspirin, is linked to a lower risk of HCC development and better survival in HCC populations. High-quality, well-designed trials should be conducted to reevaluate the relationships between NSAIDs and HCC.

The prophylactic and therapeutic effects of Momordica charantia methanol extract through controlling different hallmarks of the hepatocarcinogenesis

Inspite of the wide facilities for controlling cancer growth, there are little drugs to inhibit its metastasis or prevent its angiogenesis. Discovering such natural or synthetic multi-targeted agent that might strike different targets is considered as a vital goal for tumor controlling. In a previous study, the chemoprotective effect of methanol extract of Momordicacharantia (MEMC) on albino western rats bearing hepatocarcinogenesis was evaluated. The mechanism by which MEMC exert its anticancer properties was unknown. Therefore, we aimed in this study to investigate the possible role of MEMC as anti-proliferative, anti-angiogenic and anti-metastatic agent to exert its chemoprotective effect. The study was conducted on sixty albino western rats divided into six groups, 10 rats each. Diethylnitrosamine (DENA) was injected intraperitoneally (i.p.) at a dose of 200 mg/kg body weight once, 2 weeks later rats were received carbon tetrachloride (CCl₄₎ subcutaneously (3 ml/kg/week) continued for 10 weeks. MEMC was orally produced to rats (40 mg/kg) alone, as well as before, at the same time and after DENA injection. Cyclooxygenase-2 (COX-2), vascular endothelial growth factor (VEGF), caspase-3,-8 (Casp-3,-8), histone deacetylase (HDAC) and matrixmetalloproteinases-2,-9 (MMP-2,-9) were evaluated. MEMC treatment significantly decreased Cox-2, VEGF, HDAC and MMP-2,-9 and increased Casp-3,-8 as compared to DENAgroup,which demonstrated that the anticancer effect of MEMC may be through the inhibition of angiogenesis, proliferation and metastasis and the activation of apoptosis. The improvement in before-treated group was more pronounced than that in after- and simultaneous-treated groups, indicating thatMEMC may act as a prophylactic agent more than being a therapeutic agent.

Diselaginellin B, an Unusual Dimeric Molecule from Selaginella pulvinata, Inhibited Metastasis and Induced Apoptosis of SMMC-7721 Human Hepatocellular Carcinoma Cells

Two new unusual dimeric selaginellins, diselaginellins A and B (1 and 2), along with two known derivatives, selaginellin (3) and selaginellin B (4), were isolated from Selaginella pulvinata. Their structures were elucidated by extensive NMR and high-resolution ESIMS data analysis. Compound 2 displayed apoptosis-inducing and antimetastatic activities against the human hepatocellular carcinoma cell line SMMC-7721. A microarray analysis revealed that genes related to metabolism, angiogenesis, and metastasis were altered by 2. The up- and down-regulation of the mRNA levels of related genes was confirmed by RT-qPCR. Metabolism modulation and metastasis inhibition might be the mechanisms of the antitumor properties of diselaginellin B (2).

The effects of nonsteroidal anti-inflammatory drugs in the incident and recurrent risk of hepatocellular carcinoma: a meta-analysis

Background

Recent studies have showed that nonsteroidal anti-inflammatory drugs (NSAIDs) could reduce the risk of several types of cancer. However, epidemiological evidence of the association between NSAIDs intake and the risk of hepatocellular carcinoma (HCC) remains controversial.

Methods

To assess the preventive benefit of NSAIDs in HCC, we simultaneously searched the databases of PubMed, EmBase, Web of Science, and Scopus and screened eligible publications.

Results

A total of twelve articles (published from 2000 to 2017) from five countries were identified by retrieval. We observed a significantly lower risk of HCC incidence among users of NSAIDs than among those who did not use NSAIDs (pooled hazard ratio [HR] value =0.81, 95% confidence interval [CI]: 0.69–0.94). No evidence of publication bias was observed (Begg’s test, P=0.755; Egger’s test, P=0.564). However, when stratified according to the categories of NSAIDs, users of non-aspirin NSAIDs (HR =0.81, 95% CI: 0.70–0.94), but not aspirin (HR =0.77, 95% CI: 0.58–1.02), showed a statistically significant reduced HCC incidence. We also found that NSAIDs use significantly reduced the recurrent risk of HCC, with a HR value of 0.79 (95% CI: 0.75–0.84), whereas there was no statistically significant association between NSAIDs use and HCC mortality, with a HR value 0.65 (95% CI: 0.40–1.06).

Conclusion

Taken together, our meta-analysis demonstrates that NSAIDs significantly reduce the incident and recurrent risk of HCC.

Oleocanthal exerts antitumor effects on human liver and colon cancer cells through ROS generation

The beneficial health properties of the Mediter-ranean diet are well recognized. The principle source of fat in Mediterranean diet is extra-virgin olive oil (EVOO). Oleocanthal (OC) is a naturally occurring minor phenolic compound isolated from EVOO, which has shown a potent anti-inflammatory activity, by means of its ability to inhibit the cyclooxygenase (COX) enzymes COX-1 and COX-2. A large body of evidence indicates that phenols exhibit anticancer activities. The aim of the present study was to evaluate the potential anticancer effects of OC in hepatocellular carcinoma (HCC) and colorectal carcinoma (CRC) models. A panel of human HCC (HepG2, Huh7, Hep3B and PLC/PRF/5) and CRC (HT29, SW480) cell lines was used. Cells were treated with OC, and cell viability and apoptosis were evaluated. Compared with classical commercially available COX inhibitors (ibuprofen, indomethacin, nimesulide), OC was more effective in inducing cell growth inhibition in HCC and CRC cells. Moreover, OC inhibited colony formation and induced apoptosis, as confirmed by PARP cleavage, activation of caspases 3/7 and chromatin condensation. OC treatment in a dose dependent-manner induced expression of γH2AX, a marker of DNA damage, increased intracellular ROS production and caused mitochondrial depolarization. Moreover, the effects of OC were suppressed by the ROS scavenger N-acetyl-L-cysteine. Finally, OC was not toxic in primary normal human hepatocytes. In conclusion, OC treatment was found to exert a potent anticancer activity against HCC and CRC cells. Taken together, our findings provide preclinical support of the chemotherapeutic potential of EVOO against cancer.

An insight on the association of glycation with hepatocellular carcinoma

Hepato-cellular carcinoma (HCC) is one of the frequent cause of cancer-related death worldwide and dominant form of primary liver cancer. However, the reason behind a steady increase in the incidence of this form of cancer remains elusive. Glycation has been reported to play a significant role in the induction of several chronic diseases including cancer. Several risk factors that could induce HCC have been reported in the literature. Deciphering the complex patho-physiology associated with HCC is expected to provide new targets for the early detection, prevention, progression and recurrence. Even-though, some of the causative aspects of HCC is known, the advanced glycation end products (AGEs) related mechanism still needs further research. In the current manuscript, we have tried to uncover the possible role of glycation in the induction of HCC. In the light of the available scientific literature, we advocate in-depth comprehensive studies which will shed light towards mechanistic association of glycation with HCC.

Inhibitory effect of presenilin inhibitor LY411575 on maturation of hepatitis C virus core protein, production of the viral particle and expression of host proteins involved in pathogenicity

Hepatitis C virus (HCV) core protein is responsible for the formation of infectious viral particles and induction of pathogenicity. The C-terminal transmembrane region of the immature core protein is cleaved by signal peptide peptidase (SPP) for maturation of the core protein. SPP belongs to the family of presenilin-like aspartic proteases. Some presenilin inhibitors are expected to suppress HCV infection and production; however, this anti-HCV effect has not been investigated in detail. In this study, presenilin inhibitors were screened to identify anti-HCV compounds. Of the 13 presenilin inhibitors tested, LY411575 was the most potent inhibitor of SPP-dependent cleavage of HCV core protein. Production of intracellular core protein and supernatant infectious viral particles from HCV-infected cells was significantly impaired by LY411575 in a dose-dependent manner (half maximum inhibitory concentration = 0.27 μM, cytotoxic concentration of the extracts to cause death to 50% of viable cells > 10 μM). No effect of LY411575 on intracellular HCV RNA in the subgenomic replicon cells was detected. LY411575 synergistically promoted daclatasvir-dependent inhibition of viral production, but not that of viral replication. Furthermore, LY411575 inhibited HCV-related production of reactive oxygen species and expression of NADPH oxidases and vascular endothelial growth factor. Taken together, our data suggest that LY411575 suppresses HCV propagation through SPP inhibition and impairs host gene expressions related to HCV pathogenicity.

Effect and mechanism of resveratrol on drug resistance in human bladder cancer cells

Multidrug resistance (MDR) is a significant barrier to the effective treatment of bladder cancer. In order to improve the management of bladder cancer, it is crucial to identify strategies that may reverse MDR. The effects of three herbal medicines, ginsenoside Rh2, (−)-epigallocatechin gallate (EGCG) and resveratrol (RES) on bladder cancer were determined. The effect of these three herbal medicines against the drug resistance in adriamycin (ADM)-resistant pumc-91 cells (pumc-91/ADM) was assessed using the Cell Counting Kit-8 cell proliferation assay system. Cell cycle distribution analysis was performed using flow cytometry following treatment with RES. The mRNA and protein expression levels of multidrug resistance protein 1 (MRP1), lung resistance protein (LRP), glutathione S-transferase (GST), B cell leukemia/lymphoma-2 (BCL-2) and topoisomerase-II (Topo-II) were evaluated using reverse transcription-quantitative polymerase chain reaction and immunofluorescence, respectively. RES enhanced the cytotoxicity of anticancer agents on pumc-91/ADM cells; however, Rh2 and EGCG were unable to induce a similar effect. Additionally, RES treatment led to S phase cell cycle arrest accompanied by a decrease in the number of cells in the G1 phase. A significant decrease of MRP1, LRP, GST, BCL-2 levels and an increase of Topo-II levels were observed in RES groups compared with the control group. RES effectively reversed ADM resistance in pumc-91/ADM cells and the underlying molecular mechanism may be associated with the alteration of MRP1, LRP, GST, BCL-2 and Topo-II expression levels. Therefore, RES may be a potential candidate for reversing drug resistance in bladder cancer chemotherapy.

Ionic Liquid-assisted Synthesis of Celexocib Using Tris-(2-hydroxyethyl) Ammonium Acetate as an Efficient and Reusable Catalyst

Celecoxib is classified as none traditional nonsteroidal anti-inflammatory drugs (NSAIDs). This compound has conventional properties of NSAIDs such as anti-inflammatory, analgesic, and antipyretic activities beside reduced risk of gastrointestinal side effect of traditional NSAIDs such as ibuprofen. This compound gets a second sale rank of NSAIDs market at 2016 in the world and sales more than 17000 Kg in Iran during the past 6 month. So, a simple, rapid and green method for synthesis of this compound is important. In the present study, a novel green method was suggested for the synthesis of celecoxib using the ionic liquid. Celecoxib was provided by the reaction of trifluoroacetone, 4-methylbenzoylchloride, and 4-hydrazinobenzenesulfonamide hydrochloride. The tris-(2-hydroxyethyl) ammonium acetate as ionic liquid was prepared by mixing tris-(2-hydroxyethyl) ammonium and acetic acid, and used as an efficient catalyst. The structure of the synthetic products was confirmed by analytical and spectroscopic methods including ¹HNMR, ¹³CNMR, IR, MS and elemental analysis. This ionic liquid can play dual roles in the synthesis of celecoxib, as a catalyst to improve electrophilicity of carbonyl group and also as a solvent of reaction. The reaction rate and yield (86%) were improved considerably. Moreover IL showed the same efficiency when used in 4 consecutive reactions.

The Reversal Effect and Its Mechanisms of Tetramethylpyrazine on Multidrug Resistance in Human Bladder Cancer

Chemotherapy is an important strategy for the treatment of bladder cancer. However, the main problem limiting the success of chemotherapy is the development of multidrug resistance (MDR). To improve the management of bladder cancer, it is an urgent matter to search for strategies to reverse MDR. We chose three kinds of herbal medicines including ginsenoside Rh2, (-)-Epigallocatechin gallate (EGCG) and Tetramethylpyrazine (TMP) to detect their effects on bladder cancer. Reversal effects of these three herbal medicines for drug resistance in adriamycin (ADM)-resistant Pumc-91 cells (Pumc-91/ADM) were assessed by Cell Counting Kit-8 (CCK-8) cell proliferation assay system. The mechanisms of reversal effect for TMP were explored in Pumc-91/ADM and T24/DDP cells. After Pumc-91/ADM and T24/DDP cells were treated with TMP, cell cycle distribution analysis was performed by flow cytometry. The expression of MRP1, GST, BCL-2, LRP and TOPO-II was evaluated using quantitative real-time polymerase chain reaction (qRT-PCR), immunefluorescence assay and western blot. It was observed that TMP was capable of enhancing the cytotoxicity of anticancer agents on Pumc-91/ADM cells in response to ADM, however Rh2 and EGCG were unable to. The reversal effect of TMP was also demonstrated in T24/DDP cells. Moreover, the treatment with TMP in Pumc-91/ADM and T24/DDP cells led to an increased of G1 phase accompanied with a concomitant decrease of cell numbers in S phase. Compared to the control group, an obvious decrease of MRP1, GST, BCL-2 and an increase of TOPO-II were shown in TMP groups with a dose-dependency in mRNA and protein levels. However, there was no difference on LRP expression between TMP groups and the control group. TMP could effectively reverse MDR of Pumc-91/ADM and T24/DDP cells and its mechanisms might be correlated with the alteration of MRP1, GST, BCL-2 and TOPO-II. TMP might be a potential candidate for reversing drug resistance in bladder cancer chemotherapy.

Absence of CD66a expression is associated with high microvessel density and high histologic grade in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a primary malignancy of the liver. Patients with HCC usually have poor prognosis and high mortality. It has been shown that carcinoembryonic antigen-related cell adhesion molecule 1 (CD66a) regulates cell signaling, proliferation, and tumor growth. The aim of this study is to analyze the expression and possible role of CD66a in HCC. Immunohistochemical staining of CD66a was performed on 86 HCC cases, and microvessel density was evaluated by CD34 immunostaining. The results were further correlated with clinicopathological parameters. For 47 of 86 HCC cases, the CD66a expression showed diffuse membrane or cytoplasmic staining. The other 39 HCC cases revealed loss of CD66a expression. Loss of CD66a expression was statistically significantly associated with large tumor size (p=0.016), fatty change (p=0.039), patients with transcatheter arterial embolization (p=0.007), and high microvessel density (p=0.036). CD34 expression had no significant association with tumor size, virus infection, histological grade, and capsular invasion. The diffuse and cytoplasmic expression of CD66a may involve the early stage of the HCC, and the loss of CD66a expression indicates tumor progression.

Activating enhancer-binding protein-2α induces cyclooxygenase-2 expression and promotes nasopharyngeal carcinoma growth

Activating enhancer-binding protein-2α (AP-2α) regulates the expression of many cancer-related genes. Here, we demonstrated a novel mechanism by which AP-2α up-regulated cyclooxygenase-2 (COX-2) expression to promote the growth of nasopharyngeal carcinomas (NPCs). High expression of AP-2α in NPC cell lines and tumor tissues from NPC patients was detected and significantly correlated with COX-2 expression. Overexpression of AP-2α and COX-2 in tumor tissues was associated with advanced tumor stage, clinical progression, and short survival of patients with NPCs. Knockdown of AP-2α by siRNA markedly inhibited COX-2 expression and PGE2 production in NPC cells. Exogenous expression of AP-2α up-regulated the COX-2 and PGE2. Knockdown of AP-2α also significantly suppressed cell proliferation in NPC cells in vitro and tumor growth in a NPC xenograft mouse model. Moreover, we found that p300 played an important role in the AP-2α/COX-2 pathway. AP-2α could co-localize and interact with p300 in NPC cells. Overexpression of the p300, but not its histone acetyltransferase (HAT) domain deletion mutant, promoted the acetylation of AP-2α and its binding on the COX-2 promoter, thereby up-regulated COX-2 expression. Our results indicate that AP-2α activates COX-2 expression to promote NPC growth and suggest that the AP-2α/COX-2 signaling is a potential therapeutic target for NPC treatment.

Pseudolaric acid B circumvents multidrug resistance phenotype in human gastric cancer SGC7901/ADR cells by downregulating Cox-2 and P-gp expression

Multidrug resistance (MDR) is a challenging issue in the treatment of gastric cancer. Pseudolaric acid B is a new diterpene acid compound isolated from pseudolarix, which has been found to have anti-tumor activities in recent studies. The purpose of the present study was to evaluate the effects of pseudolaric acid B in an MDR gastric cancer cell line and elucidate the possible underlying mechanisms of action. SGC7901/ADR, a P-glycoprotein (P-gp)-overexpressing cell line, was used to evaluate the efficacy of pseudolaric acid B against MDR phenotypes. The effects of pseudolaric acid B and chemotherapeutic agents on cell proliferation and apoptosis were assessed using the MTT assay and flow cytometry, respectively. Immunocytochemistry and Western blot were used to detect the possible relevant molecules in order to elucidate the underlying mechanism of action. The results showed that pseudolaric acid B inhibited cell proliferation and induced apoptosis in SGC7901/ADR cells. A low dose of pseudolaric acid B (0.5 µmol/L) augmented the inhibitory effects of chemotherapeutic agents on proliferation (p < 0.05). The expression of P-gp and cyclooxygenase 2 (Cox-2) was downregulated with pseudolaric acid B treatment. The present results showed that pseudolaric acid B inhibited cell proliferation, induced apoptosis, circumvented MDR, and increased the sensitivity of chemotherapeutic agents in vitro by downregulating the expression of P-gp and Cox-2.

A randomised controlled trial of meloxicam, a Cox-2 inhibitor, to prevent hepatocellular carcinoma recurrence after initial curative treatment

Background

Because the recurrence rate of hepatocellular carcinoma (HCC) is high, even after curative treatments such as hepatic resection and microwave ablation, chemopreventive agents that can effectively suppress HCC recurrence are required. Cyclooxygenase-2 (Cox-2) was recently found to be overexpressed in HCC. Therefore, Cox-2 inhibitors may offer a chemopreventive therapy for HCC. This randomised controlled trial (RCT) investigated the potential for meloxicam, a clinically used Cox-2 inhibitor, to prevent HCC recurrence after initial curative treatment.

Methods

A total of 232 consecutive patients underwent hepatic resection and/or microwave ablation as initial therapy for HCC at our institute between July 2008 and April 2011. Eight patients were excluded because of poor renal function, history of non-steroidal anti-inflammatory drug-related ulceration, or multiple cancers. The remaining 224 patients were randomised to a control group (n = 113) or a meloxicam group (n = 111). To patients in the meloxicam group, meloxicam was administered at 15 mg daily (5 mg three times a day) as long as possible. The overall survival (OS) and disease-free survival (DFS) rates were determined.

Results

The 1-, 3-, and 5-year OS rates of the meloxicam group were 95.4, 82.4, and 70.1 %, respectively. Those of the control group were 98.2, 85.1, and 71.5 %, respectively (p = 0.9549). The corresponding DFS rates of the meloxicam group were 89.2, 53.9, and 44.0 % and those of control group were 86.5, 57.0, and 43.4 %, respectively (p = 0.6722). In the OS and DFS of subsets including patients with hepatitis B or C virus infection, we could not find significant differences between the meloxicam and control groups. However, in the subgroup of analysis of patients without viral hepatitis (NBNC-HCC), significant differences were observed in the DFS between the meloxicam group (1-year DFS, 92.3 %; 3-year DFS, 75.8 %; 5-year DFS, 70.4 %) and control group (1-year DFS, 83.3 %; 3-year DFS, 48.1 %; 5-year DFS, not obtained) (p = 0.0211).

Conclusion

Administration of the Cox-2 inhibitor meloxicam may have a possibility to suppress HCC recurrence after initial curative treatments in patients with NBNC-HCC.

NSAID Use and Risk of Hepatocellular Carcinoma and Intrahepatic Cholangiocarcinoma: The Liver Cancer Pooling Project

Chronic inflammation plays a pivotal role in the pathogenesis of hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC), the two most common types of liver cancer. A number of prior experimental studies have suggested that nonsteroidal anti-inflammatory drugs (NSAIDs), including aspirin and ibuprofen, may potentially protect against liver cancer. However, no observational study has examined the association between aspirin duration and dose or other over-the-counter non-aspirin NSAIDs, such as ibuprofen, and liver cancer incidence. Furthermore, the association between NSAID use and risk of ICC is unclear. As part of the Liver Cancer Pooling Project, we harmonized data on 1,084,133 individuals (HCC = 679, ICC = 225) from 10 U.S.-based prospective cohort studies. Cox proportional hazards regression models were used to evaluate multivariable-adjusted HRs and 95% confidence intervals (CI). Current aspirin use, versus nonuse, was inversely associated with HCC (HR, 0.68; 95% CI, 0.57-0.81), which persisted when restricted to individuals not using non-aspirin NSAIDs and in a 5- and 10-year lag analysis. The association between aspirin use and HCC risk was stronger for users who reported daily use, longer duration use, and lower dosage. Ibuprofen use was not associated with HCC risk. Aspirin use was associated with a reduced ICC risk in men (HR, 0.64; 95% CI, 0.42-0.98) but not women (HR, 1.34; 95% CI, 0.89-2.01; P(interaction) = 0.01). The observed inverse association between aspirin use and liver cancer in our study, together with previous data, suggests the merit of future intervention studies of aspirin and other agents that affect chronic inflammatory pathways for HCC and possibly ICC.

Inflammation and cancer: inhibiting the progression of residual hepatic VX2 carcinoma by anti-inflammatory drug after incomplete radiofrequency ablation

BACKGROUND

Accelerated progression of residual hepatocellular carcinoma (HCC) after incomplete radiofrequency ablation (RFA) has been reported more frequently. Recent data have redefined the concept of inflammation as a critical component of tumor progression. However, there has been little understanding regarding the relationship between progression of residual HCC and the inflammation induced by thermal destruction of the tumor after RFA. The present study was designed to determine whether inflammation facilitates rapid progression of residual hepatic VX2 carcinoma and to clarify the possible underlying mechanisms.

METHODS

Forty-eight rabbits were each implanted with two VX2 hepatic tumors via supraumbilical median laparotomy. One of the tumors in two different lobes was ablated by RFA. All the rabbits were then randomly divided into four groups (12 rabbits in each group) receiving anti-inflammatory treatment with different doses of aspirin: control group, AS-L group (aspirin, 5 mg/kg/d), AS-M group (aspirin, 20 mg/kg/d), and AS-H group (aspirin, 100 mg/kg/d). The levels of serum interleukin-6 (IL-6), high sensitivity C-reactive protein (hs-CRP), and tumor necrosis factor-α (TNF-α) were detected to evaluate the effect of the anti-inflammation. Tumor growth, lung and kidney metastasis, and survival were assessed. The expression of proliferating cell nuclear antigen (PCNA), matrix metalloproteinase 9 (MMP-9), vascular endothelial growth factor (VEGF), and cysteinyl aspartate specific proteinase 3 (caspase-3) in residual tumor was examined by immunohistochemistry and Western-blotting.

RESULTS

The levels of serum IL-6, hs-CRP, and TNF-α in the AS-H group decreased significantly in comparison with those of the control group (P<0.05). The focal tumor volume and lung and kidney metastases of rabbits in the AS-H group were less significant compared with those of the control group (P<0.05). The expression of PCNA, MMP-9, and VEGF in the AS-H group decreased significantly compared with the control group (P<0.05). Finally, the survival time of the AS-H group was longer than that of the control group (P<0.05).

CONCLUSIONS

Inflammation induced by thermal destruction of the tumor following RFA could be an important cause of rapid progression of residual hepatic VX2 carcinoma. The anti-inflammation effect of aspirin can inhibit proliferation, invasion, and metastasis of residual tumor cells, and aspirin may be a good candidate drug as an adjuvant therapy with RFA for treating HCC.

Mcl-1 is an important therapeutic target for oral squamous cell carcinomas

Oral and oropharyngeal cancers are the sixth most common cancers worldwide. Despite intensive investigation, oral squamous cell carcinomas (OSCC) represent a clinical challenge resulting in significant morbidity and mortality. Resistance to cell death is common in OSCC and is often mediated by the Bcl-2 family proteins. Among all anti-apoptotic Bcl-2 family members, Mcl-1 functions as a major survival factor, particularly in solid cancers. Despite the confirmed importance of Mcl-1 in several neoplasms, the role of Mcl-1 in OSCC survival has yet to be explored. In this study, we found that knocking down Mcl-1 sensitized OSCC cells to ABT-737, which binds to Bcl-2/Bcl-xL but not Mcl-1. We report for the first time that a BH3 mimetic, Sabutoclax, which functions as an inhibitor of all anti-apoptotic Bcl-2 proteins, induced cancer-specific cell death in an Mcl-1-dependent manner through both apoptosis and toxic mitophagy. In vivo studies demonstrated that Sabutoclax alone decreased tumor growth in a carcinogen-induced tongue OSCC mouse model. In a combination regimen, Sabutoclax and COX-2 inhibitor, Celecoxib, synergistically inhibited the growth of OSCC in vitro and also significantly reduced OSCC tumor growth in vivo. Overall, these results identify Mcl-1 as a therapeutic prospective target in OSCC.

Nonsteroidal anti-inflammatory drugs are associated with reduced risk of early hepatocellular carcinoma recurrence after curative liver resection: a nationwide cohort study

PURPOSE

The efficacy of nonsteroidal anti-inflammatory drugs (NSAIDs) in reducing the risk of various de novo cancers has been reported; however, its role in reducing hepatocellular carcinoma (HCC) recurrence after liver resection still remains unknown.

METHODS

We have conducted a nationwide cohort study by recruiting all patients with a newly diagnosed HCC who had received curative liver resection as their initial treatment. The use of NSAIDs and the risk of early HCC recurrence have been examined by multivariate and stratified analyses. To avoid immortal time bias, the use of NSAIDs has been treated as a time-dependent variable in Cox proportional hazard ratio models.

RESULTS

Between January 1997 and December 2010, a total of 15,574 HCC patients who had received liver resection were enrolled in this study. The 1-, 3-, and 5-year overall survival rates were 90.4%, 73.2%, and 59.8%, respectively. The 1-, 3-, and 5-year disease-free survival rates were 80.5%, 59.4%, and 50.2%, respectively. NSAID use (hazard ratio, 0.81; 95% confidence interval, 0.73-0.90) and minor liver resection (hazard ratio, 0.83; 95% confidence interval, 0.78-0.89) were independently associated with a reduced risk of early HCC recurrence after liver resection. In the stratified analyses, NSAID usage was universally associated with reduced risks in most subgroups, particularly for those aged younger than 65 years, male, with underlying diabetes mellitus and receiving major liver resection.

CONCLUSIONS

The use of NSAIDs can be associated with a reduced risk of early HCC recurrence within 2 years after curative liver resection, regardless of patients' age, extent of liver resection, viral hepatitis status, underlying diabetes, and liver cirrhosis.

Study of the effects of cyclooxygenase-2 inhibitor on the promotion of hepatic tumorigenesis in rats fed a high fat diet

BACKGROUND/OBJECTIVE

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide. The highest prevalence of hepatitis is an important risk factor contributing to development of HCCs. However, an increasing number of cases are associated metabolic disease and steatohepatitis. Inflammation associated with many liver disease, seems to be a necessary pre-requisite for successful tumor initiation. Mechanisms that link high fat diet and inflammation initial stage of HCC are not completely understood. The present work was designed to investigate the effect of fat, through modulation of the insulin-like growth factors I and II (IGF-I and IGF-II), on the promotion of hepatocellular carcinoma, and the role of cyclooxygenase 2 (COX-2).

METHODS

two main groups of rats were used: control and HCC groups. The HCC group was further sub-divide in to two subgroups, HCC fed with standard diet and HCC fed with high fat diet. The effects of celecoxib were also investigated in HCC fed with high fat diet.

RESULTS

We found that high fat diet was associated with significant increases in COX2 and interleukin 6 (IL6) with significant promotion of HCC progression. The significant increase in IGF could contribute partially to the observed effects of high fat diet. In addition, celecoxib was found to significantly reduce HCC progression.

CONCLUSIONS

We conclude that COX2 could play central role in high prevalence of HCC observed with high fat diet. Several triggering factors such as IGF and IL6, together with the direct modulation of fat metabolism could open several novel preventive strategies of celecoxib treatment, and could be useful biomarkers for assessment of its pharmacological effects.

Reversal of Multidrug Resistance by the Chinese Medicine Yiqi Jianpi Huaji Decoction and the Mechanism of Action in Human Gastric Cancer SGC7901/VCR Cells

Yiqi Jianpi Huaji Decoction (YJHD), a traditional Chinese medicinal formula composed of twelve ingredients, has recently been reported to have a good clinical curative effect. The purpose of the present study was to evaluate the effects of YJHD on SGC7901/VCR gastric cancer cells and to elucidate the possible mechanism of action. First, the effects of a low dose of YJHD in combination with chemotherapeutic agents on SGC7901/VCR cells were assessed using the CCK-8 assay and flow cytometry, and the effects of YJHD on genes and proteins involved in drug resistance (MDR1, MRP, TUBB3, STMN1, and TS) were evaluated. Furthermore, transfection of SGC7901/VCR cells with siRNAs targeting these genes inhibited their expression, and the efficacy of vincristine against the cells was dramatically improved in vitro when these genes were silenced. These results demonstrate that low-dose YJHD inhibited cell proliferation, induced apoptosis, reversed MDR, and increased sensitivity to chemotherapeutic agents in vitro by downregulating P-gp, MRP, TUBB3, and STMN1 expression. MDR can be reversed by siRNAs targeting genes involved in MDR, and this strategy for cancer treatment should be evaluated in future studies.

Association between C-reactive protein, incident liver cancer, and chronic liver disease mortality in the Linxian Nutrition Intervention Trials: a nested case-control study

BACKGROUND

C-reactive protein (CRP) is a marker of systemic inflammation that has been associated with the incidence and prognosis for a number of different cancers. Recent data suggest that CRP may be a prognostic factor for liver cancer and cirrhosis. However, few long-term studies are available.

METHODS

We prospectively examined associations between serum CRP and subsequent risk of liver cancer incidence or chronic liver disease mortality in a nested case-control study performed in the Linxian Nutrition Intervention Trials cohort. Baseline serum CRP was measured for 220 incident liver cancer cases, 276 participants who died of chronic liver disease, and 1,018 age-, sex-, and trial-matched controls. Unconditional logistical regression models were used to estimate ORs and 95% confidence intervals (CI).

RESULTS

Compared with the lowest quartile, subjects in the fourth quartile of serum CRP had a higher risk of liver cancer incidence (OR, 1.63; 95% CI, 1.06-2.51), with a significant Ptrend across quartiles (P = 0.01). The association with liver cancer was only significant among men (Q4 vs. Q1; OR, 2.00; 1.10-3.62), but not among women (Q4 vs. Q1; OR, 1.15; 0.60-2.22). For chronic liver disease deaths, the corresponding risk estimate in men and women was 2.95 (1.90-4.57), with a monotonic trend (P < 0.001).

CONCLUSIONS

Higher serum CRP concentrations at baseline were associated with subsequent incidence of liver cancer and death from chronic liver disease.

IMPACT

Our findings suggest that levels of systemic inflammation may serve as a long-term marker of liver cancer and liver disease.

Celecoxib suppresses hepatoma stemness and progression by up-regulating PTEN

Celecoxib, a COX-2 inhibitor and non-steroidal anti-inflammatory drug, can prevent several types of cancer, including hepatocellular carcinoma (HCC). Here we show that celecoxib suppressed the self-renewal and drug-pumping functions in HCC cells. Besides, celecoxib depleted CD44+/CD133+ hepatic cancer stem cells (hCSC). Prostaglandin E2 (PGE2) and CD133 overexpression did not reverse the celecoxib-induced depletion of hCSC. Also, celecoxib inhibited progression of rat Novikoff hepatoma. Moreover, a 60-day celecoxib program increased the survival rate of rats with hepatoma. Histological analysis revealed that celecoxib therapy reduced the abundance of CD44+/CD133+ hCSCs in hepatoma tissues. Besides, the hCSCs depletion was associated with elevated apoptosis and blunted proliferation and angiogenesis in hepatoma. Celecoxib therapy activated peroxisome proliferator-activated receptor γ (PPARγ) and up-regulated PTEN, thereby inhibiting Akt and disrupting hCSC expansion. PTEN gene delivery by adenovirus reduced CD44/CD133 expression in vitro and hepatoma formation in vivo. This study suggests that celecoxib suppresses cancer stemness and progression of HCC via activation of PPARγ/PTEN signaling.

Oxidative stress and cell damage in a model of precancerous lesions and advanced hepatocellular carcinoma in rats

Hepatocellular carcinoma (HCC) is the third most frequent cause of cancer deaths throughout the world. This study was aimed to analyze oxidative stress and cell damage in a multistage model of liver carcinogenesis induced by diethylnitrosamine (DEN) in rats. Male Wistar rats weighing 145–150 g were divided into three groups: control, precancerous lesions (PL) (which received 100 mg DEN once a week every 6 weeks up to 28 weeks), and advanced HCC (50 mg DEN once/twice per week up to 19 weeks). Lipid peroxidation (TBARS), superoxide dismutase (SOD) activity, and expression of transforming growth factor-1 beta (TGF)-1β, endothelial and inducible nitric oxide syntahese (eNOS, iNOS), NADPH quinone oxireductase (NQO)-1, nuclear factor erythroid 2-related factor (NrF)2, kelch-like ECH-associated protein (Keap)1 and heat shock protein (HSP)70 were measured. TBARS concentration was augmented in the PL and advanced HCC groups. SOD activity, TGF-1β and Nrf2 expression were higher in animals with precancerous lesions. In advanced HCC, expression of NQO1 and iNOS increased while there was a decrease in HPS70 expression. Data obtained provide evidence for the differential activation of proteins involved in oxidative stress and cell damage during progression of carcinogenesis in an animal model of HCC.

The role of inflammation and liver cancer

Persistent inflammation is known to promote and exacerbate malignancy. Primary liver cancer, mostly hepatocellular carcinoma (HCC), is a clear example of inflammation-related cancer as more than 90 % of HCCs arise in the context of hepatic injury and inflammation. HCC represents the fifth most common malignancy and the third leading cause of cancer-related death worldwide with about one million new cases diagnosed every year with almost an equal number of deaths. Chronic unresolved inflammation is associated with persistent hepatic injury and concurrent regeneration, leading to sequential development of fibrosis, cirrhosis, and eventually HCC. Irrespective of the intrinsic differences among various etiological factors, a common denominator at the origin of HCC is the perpetuation of a wound-healing response activated by parenchymal cell death and the resulting inflammatory cascade. Hence, the identification of fundamental inflammatory signaling pathways causing transition from chronic liver injury to dysplasia and HCC could depict new predictive biomarkers and targets to identify and treat patients with chronic liver inflammation. This chapter critically discusses the roles of several major cytokines, chemokines, growth factors, transcription factors, and enzymes as well as a distinct network of inflammatory signaling pathways in the development and progression of HCC. It also highlights and analyzes preclinical animal studies showing innovative approaches of targeting inflammatory mediators and signaling by a variety of natural compounds and synthetic agents to achieve effective therapy as well as prevention of hepatic malignancy. Additionally, current limitations and potential challenges associated with the inhibition of inflammatory signaling as well as future directions of research to accelerate clinical development of anti-inflammatory agents to prevent and treat liver cancer are presented.

Population-based epidemiology, malignancy risk, and outcome of primary sclerosing cholangitis

Extensive population-based studies are much needed to accurately establish epidemiology and disease course in patients with primary sclerosing cholangitis (PSC). We aimed to obtain population-based prevalence and incidence figures, insight in disease course with regard to survival, liver transplantation (LT), and occurrence of malignancies, as well as risk factors thereof. Four independent hospital databases were searched in 44 hospitals in a large geographically defined area of the Netherlands, comprising 50% of the population. In addition, all PSC patients in the three Dutch liver transplant centers and all inflammatory bowel disease (IBD) patients in the adherence area of a large district hospital were identified. All medical records were reviewed on-site, verifying diagnosis. Five hundred and ninety PSC patients were identified, resulting in an incidence of 0.5 and a point prevalence of 6.0 per 100,000. Median follow up was 92 months. Estimated median survival from diagnosis until LT or PSC-related death in the entire cohort was 21.3 years, as opposed to 13.2 years in the combined transplant centers cohort (n = 422; P < 0.0001). Colorectal carcinoma (CRC) risk was 10-fold increased, as compared to ulcerative colitis controls, and developed at a much younger age (39 years; range, 26-64), compared to IBD controls (59 years; range, 34-73; P = 0.019). Colonoscopic surveillance was associated with significantly better outcome.

CONCLUSION

This study exemplifies that, for relatively rare diseases, it is paramount to collect observational data from large, population-based cohorts, because incidence and prevalence rates of PSC are markedly lower and survival much longer than previously reported. The selection of a bias-free, population-based cohort showed a significantly longer survival, compared to the tertiary referral cohort. CRC can develop at an early age, warranting surveillance from time of PSC diagnosis.

Novel combination of sorafenib and celecoxib provides synergistic anti-proliferative and pro-apoptotic effects in human liver cancer cells

Molecular targeted therapy has shown promise as a treatment for advanced hepatocellular carcinoma (HCC). Sorafenib, a multikinase inhibitor, recently received FDA approval for the treatment of advanced HCC. However, although sorafenib is well tolerated, concern for its safety has been expressed. Celecoxib (Celebrex®) is a selective cyclooxygenase-2 (COX-2) inhibitor which exhibits antitumor effects in human HCC cells. The present study examined the interaction between celecoxib and sorafenib in two human liver tumor cell lines HepG2 and Huh7. Our data showed that each inhibitor alone reduced cell growth and the combination of celecoxib with sorafenib synergistically inhibited cell growth and increased apoptosis. To better understand the molecular mechanisms underlying the synergistic antitumor activity of the combination, we investigated the expression profile of the combination-treated liver cancer cell lines using microarray analysis. Combination treatment significantly altered expression levels of 1,986 and 2,483 transcripts in HepG2 and Huh7 cells, respectively. Genes functionally involved in cell death, signal transduction and regulation of transcription were predominantly up-regulated, while genes implicated in metabolism, cell-cycle control and DNA replication and repair were mainly down-regulated upon treatment. However, combination-treated HCC cell lines displayed specificity in the expression and activity of crucial factors involved in hepatocarcinogenesis. The altered expression of some of these genes was confirmed by semi-quantitative and quantitative RT-PCR and by Western blotting. Many novel genes emerged from our transcriptomic analyses, and further functional analyses may determine whether these genes can serve as potential molecular targets for more effective anti-HCC strategies.

Proinflammatory conditions promote hepatocellular carcinoma onset and progression via activation of Wnt and EGFR signaling pathways

The aim of the current study was to investigate how proinflammatory conditions affect growth and progression of hepatocellular carcinoma. Human hepatoma cell lines were treated with lipopolysaccharide (LPS) or cyclooxygenase-2 inhibitor, Celecoxib, and in vitro proliferation, apoptosis, and cell cycle progression were assessed. This was followed up with in vivo xenograft assays to monitor tumor growth and metastatic progression under different treatment conditions. While LPS induced cell proliferation, Celecoxib induced apoptosis. Flow cytometry analysis demonstrated that S-phase cell count in LPS group was higher than control group (41.9 ± 3.2 vs 30.6 ± 0.1%, respectively), whereas G0/G1-phase cells were significantly higher in the Celecoxib group in comparison with the control group (69.6 ± 5.0 vs 50.4 ± 1.6%, respectively) (p < 0.05). Immunoblot analyses showed induction of epidermal growth factor receptor expression and induction and nuclear accumulation of Wnt/β-catenin and p65 in LPS group. Xenograft assays showed that LPS treatment induced comparatively large, rapidly growing tumors (2,702 ± 572 mm(3)) that metastasized to lungs, whereas Celecoxib treatment alone (1,008 ± 296 mm(3)) or in combination with LPS (1,303 ± 283 mm(3)) suppressed tumor growth in comparison to control groups (2,072 ± 456 mm(3)) (n = 5; p < 0.05). Inflammation can thus promote hepatoma cell proliferation and growth, and enhance the invasion and metastatic ability of hepatocarcinoma cells through inducing tumor angiogenesis, which in turn may be related to the activation of Wnt/β-catenin and EGFR signaling pathways.

15-PGDH inhibits hepatocellular carcinoma growth through 15-keto-PGE2/PPARγ-mediated activation of p21WAF1/Cip1

15-hydroxyprostaglandin dehydrogenase (15-PGDH) is a key enzyme in prostaglandin metabolism. This study provides important evidence for inhibition of hepatocellular carcinoma (HCC) growth by 15-PGDH through the 15-keto-PGE₂/PPARγ/p21^WAF1/Cip1 signaling pathway. Forced overexpression of 15-PGDH inhibited HCC cell growth in vitro, whereas knockdown of 15-PGDH enhanced tumor growth parameters. In a tumor xenograft model in SCID mice, inoculation of human HCC cells (Huh7) with overexpression of 15-PGDH led to significant inhibition of tumor growth, while knockdown of 15-PGDH enhanced tumor growth. In a separate tumor xenograft model in which mouse HCC cells (Hepa1-6) were inoculated into syngeneic C57BL/6 mice, intratumoral injection of adenovirus vector expressing 15-PGDH (pAd-15-PGDH) significantly inhibited xenograft tumor growth. The anti-tumor effect of 15-PGDH is mediated through its enzymatic product, 15-keto-PGE₂, which serves as an endogenous PPARγ ligand. Activation of PPARγ by 15-PGDH-derived 15-keto-PGE₂ enhanced the association of PPARγ with the p21^WAF1/Cip1 promoter and increased p21 expression and association with CDK2, CDK4 and PCNA. Depletion of p21 by shRNA reversed 15-PGDH-induced inhibition of HCC cell growth; overexpression of p21 prevented 15-PGDH knockdown-induced tumor cell growth. These results demonstrate a key 15-PGDH/15-keto-PGE₂-mediated activation of PPARγ and p21^WAF1/Cip1 signaling cascade that regulates hepatocarcinogenesis and tumor progression.

Synthesis and characterization of celecoxib derivatives as possible anti-inflammatory, analgesic, antioxidant, anticancer and anti-HCV agents

A series of novel N-(3-substituted aryl/alkyl-4-oxo-1,3-thiazolidin-2-ylidene)-4-[5-(4-methylphenyl)-3-(trifluoromethyl)-1H-pyrazol-1-yl]benzenesulfonamides 2a-e were synthesized by the addition of ethyl a-bromoacetate and anhydrous sodium acetate in dry ethanol to N-(substituted aryl/alkylcarbamothioyl)-4-[5-(4-methylphenyl)-3-(trifluoro-methyl)-1H-pyrazol-1-yl]benzene sulfonamides 1a-e, which were synthesized by the reaction of alkyl/aryl isothiocyanates with celecoxib. The structures of the isolated products were determined by spectral methods and their anti-inflammatory, analgesic, antioxidant, anticancer and anti-HCV NS5B RNA-dependent RNA polymerase (RdRp) activities evaluated. The compounds were also tested for gastric toxicity and selected compound 1a was screened for its anticancer activity against 60 human tumor cell lines. These investigations revealed that compound 1a exhibited anti-inflammatory and analgesic activities and further did not cause tissue damage in liver, kidney, colon and brain compared to untreated controls or celecoxib. Compounds 1c and 1d displayed modest inhibition of HCV NS5B RdRp activity. In conclusion, N-(ethylcarbamothioyl)-4-[5-(4-methylphenyl)-3-(trifluoromethyl)-1H-pyrazol-1-yl]benzenesulfonamide (1a) may have the potential to be developed into a therapeutic agent.