Anti-inflammatory Effect of Pitavastatin on NF-.KAPPA.B Activated by TNF-.ALPHA. in Hepatocellular Carcinoma Cells

Statin therapy: a potential adjuvant to immunotherapies in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most prevalent cancers worldwide and accounts for more than 90% of primary liver cancer. The advent of immune checkpoint inhibitor (ICI)-related therapies combined with angiogenesis inhibition has revolutionized the treatment of HCC in late-stage and unresectable HCC, as ICIs alone were disappointing in treating HCC. In addition to the altered immune microenvironment, abnormal lipid metabolism in the liver has been extensively characterized in various types of HCC. Stains are known for their cholesterol-lowering properties and their long history of treating hypercholesterolemia and reducing cardiovascular disease risk. Apart from ICI and other conventional therapies, statins are frequently used by advanced HCC patients with dyslipidemia, which is often marked by the abnormal accumulation of cholesterol and fatty acids in the liver. Supported by a body of preclinical and clinical studies, statins may unexpectedly enhance the efficacy of ICI therapy in HCC patients through the regulation of inflammatory responses and the immune microenvironment. This review discusses the abnormal changes in lipid metabolism in HCC, summarizes the clinical evidence and benefits of stain use in HCC, and prospects the possible mechanistic actions of statins in transforming the immune microenvironment in HCC when combined with immunotherapies. Consequently, the use of statin therapy may emerge as a novel and valuable adjuvant for immunotherapies in HCC.

Association of Statin Use With Risk of Liver Disease, Hepatocellular Carcinoma, and Liver-Related Mortality

Importance

Given the burden of chronic liver disease on the health care system, more information on the hepatoprotective association of statins in the general population is needed.

Objective

To examine whether regular statin use is associated with a reduction in liver disease, particularly hepatocellular carcinoma (HCC) and liver-related deaths, in the general population.

Design, Setting, and Participants

This cohort study used data from the UK Biobank (UKB) (individuals aged 37-73 years) collected from baseline (2006-2010) to the end of follow-up in May 2021, from the TriNetX cohort (individuals aged 18-90 years) enrolled from baseline (2011-2020) until end of follow-up in September 2022, and from the Penn Medicine Biobank (PMBB) (individuals aged 18-102 years) with ongoing enrollment starting in 2013 to the end of follow-up in December 2020. Individuals were matched using propensity score matching according to the following criteria: age, sex, body mass index, ethnicity, diabetes with or without insulin or biguanide use, hypertension, ischemic heart disease, dyslipidemia, aspirin use, and number of medications taken (UKB only). Data analysis was performed from April 2021 to April 2023.

Exposure

Regular statin use.

Main Outcomes and Measures

Primary outcomes were liver disease and HCC development as well as liver-associated death.

Results

A total of 1 785 491 individuals were evaluated after matching (aged 55 to 61 years on average, up to 56% men, and up to 49% women). A total of 581 cases of liver-associated death, 472 cases of incident HCC, and 98 497 new liver diseases were registered during the follow-up period. Individuals were aged 55-61 years on average, with a slightly higher proportion of men (up to 56%). In UKB individuals (n = 205 057) without previously diagnosed liver disease, statin users (n = 56 109) had a 15% lower hazard ratio (HR) for the association of developing a new liver disease (HR, 0.85; 95% CI, 0.78-0.92; P < .001). In addition, statin users demonstrated a 28% lower HR for the association with liver-related death (HR, 0.72; 95% CI, 0.59-0.88; P = .001) and a 42% lower HR for the development of HCC (HR, 0.58; 95% CI, 0.35-0.96; P = .04). In TriNetX individuals (n = 1 568 794), the HR for the association of HCC was reduced even further for statin users (HR, 0.26; 95% CI, 0.22-0.31; P = .003). The hepatoprotective association of statins was time and dose dependent, with a significant association in PMBB individuals (n = 11 640) for incident liver diseases after 1 year of statin use (HR, 0.76; 95% CI, 0.59-0.98; P = .03). Taking statins was particularly beneficial in men, individuals with diabetes, and individuals with a high Fibrosis-4 index at baseline. Carriers of the heterozygous minor allele of PNPLA3 rs738409 benefited from statin use and had a 69% lower HR for the association with HCC (UKB HR, 0.31; 95% CI, 0.11-0.85; P = .02).

Conclusions and Relevance

This cohort study indicates substantial preventive associations of statins against liver disease, with an association with duration and dose of intake.

Pitavastatin-loaded bilosomes for oral treatment of hepatocellular carcinoma: a repurposing approach

Albeit its established efficacy as an anti-hyperlipidemic agent, pitavastatin (PIT) has been shown to have other various therapeutic effects. One of these effects is the anti-cancer activity against hepatocellular carcinoma (HCC). This effect has been evaluated in this study for the first time via its oral delivery loaded in bilosomes both in vitro in hepatocellular carcinoma (HCC) cell line; HepG2 and in vivo in an Ehrlich ascites carcinoma (EAC) model. Moreover, the impact of surface modification of bilosomes with lactoferrin (LF) as an active targeting ligand for HCC was investigated. Bilosomes were prepared by thin-film hydration and different molar phospholipid to bile salt ratios were used to optimize the bilosomal formulation. The molar phospholipid to bile salt ratio was adjusted to 4:1 at pH 7.4. LF-coated bilosomes possessed a particle size, PDI, entrapment efficiency, and zeta potential of 112.28 nm ± 6.35, 0.229 ± 0.06, 90.56% ± 3.22, and −7.86 mV ± 1.13, respectively. LF-coated bilosomes also increased permeation of PIT when tested on Caco-2 cells by 3.1-folds (compared to uncoated ones or free PIT solution). It also improved the cytotoxicity of HepG2 spheroids 44-folds more than PIT-free solution. RT-PCR analysis showed that LF-coated PIT-loaded bilosomes caused an improvement (2-fold increase) in the apoptotic potential of PIT mediated by caspase-3. In conclusion, the optimized LF-coated PIT-loaded bilosomes were cytotoxic to HCC with improved hepatocytes permeation and cellular uptake. Thus, the proposed formula could be a promising treatment for HCC.

Pitavastatin Combined with Ezetimibe Treatment was an Effective Approach to Non-IRA Lesion of ST-segment Elevation Myocardial Infarction Patients with Primary Percutaneous Coronary Intervention

OBJECTIVE

ST-Segment Elevation Myocardial Infarction (STEMI) patients with the multivessel disease have distinctive plaque characteristics in non-IRA lesions. Intensive statin therapy was a potential approach to treat STEMI patients with the non-IRA disease. However, there is still poor evidence about the therapeutic effect. In this study, we have evaluated the detailed therapeutic effect of statin plus ezetimibe intensive therapy.

METHODS

For STEMI patients with non-IRA disease undergoing primary Percutaneous Coronary Intervention (PCI), 183 control STEMI patients without non-IRA disease undergoing primary PCI, and 200 STEMI patients with non-IRA disease undergoing primary PCI were introduced into this study. 200 STEMI patients with non-IRA disease undergoing primary PCI were divided into Normal group, Intensive group, Normal & Combined group, and Intensive & Combined group. The baseline information for each participant was recorded. Meanwhile, the physiological and biochemical indicators of each member with different treatments were collected after one-year follow-up.

RESULTS

For STEMI patients with non-IRA disease undergoing primary PCI, no differences could be detected in multiple indexes such as OCT examination results, age, stroke, etc. However, diabetes mellitus, smoking, and coronary Gensini score were different between different groups (P<0.05). After one year follow-up, cholesterol, low-density lipoprotein, coronary Gensini score, thin-cap fibroatheroma, length of non-infarcted arterial lesions, non-infarct artery lesion range, myocardial infarction again, and revascularization again were significantly different between different groups (P<0.05).

CONCLUSION

The results mentioned above suggested that pitavastatin combined with ezetimibe was an effective approach for STEMI patients with non-IRA disease undergoing primary PCI. The results obtained in this study have provided a novel method for the treatment of STEMI patients with non-IRA disease undergoing primary PCI.

Interpreting the Molecular Mechanisms of Yinchenhao Decoction on Hepatocellular Carcinoma through Absorbed Components Based on Network Pharmacology

To investigate the mechanisms through which Yinchenhao decoction (YCHD) inhibits hepatocellular carcinoma (HCC), we analyzed YCHD ingredients absorbed into the bloodstream by using network pharmacology. We conducted a weighted gene coexpression network analysis on gene expression data collected from the Gene Expression Omnibus and The Cancer Genome Atlas databases to derive an HCC gene set; moreover, we used four online prediction system databases to predict the potential targets of YCHD ingredients absorbed into the bloodstream. We discovered that YCHD directly interfered with 17 HCC-related disease targets. Subsequent gene ontology enrichment analyses of these 17 disease targets revealed that YCHD exhibited effects through 17 biological processes, 7 molecular functions, and 9 cellular components. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses indicated 14 pathways through which YCHD inhibits HCC. We observed similar trends in how the 17 small molecules interfered with the key target set. We surmised that YCHD inhibits HCC by regulating inflammatory and metabolic pathways. Network pharmacological analysis of YCHD ingredients absorbed into the bloodstream may provide new insights and serve as a new method for discovering the molecular mechanisms through which YCHD inhibits HCC.

Risk Factors, Pathogenesis, and Strategies for Hepatocellular Carcinoma Prevention: Emphasis on Secondary Prevention and Its Translational Challenges

Hepatocellular carcinoma (HCC) is a leading cause of cancer-associated mortality globally. Given the limited therapeutic efficacy in advanced HCC, prevention of HCC carcinogenesis could serve as an effective strategy. Patients with chronic fibrosis due to viral or metabolic etiologies are at a high risk of developing HCC. Primary prevention seeks to eliminate cancer predisposing risk factors while tertiary prevention aims to prevent HCC recurrence. Secondary prevention targets patients with baseline chronic liver disease. Various epidemiological and experimental studies have identified candidates for secondary prevention-both etiology-specific and generic prevention strategies-including statins, aspirin, and anti-diabetic drugs. The introduction of multi-cell based omics analysis along with better characterization of the hepatic microenvironment will further facilitate the identification of targets for prevention. In this review, we will summarize HCC risk factors, pathogenesis, and discuss strategies of HCC prevention. We will focus on secondary prevention and also discuss current challenges in translating experimental work into clinical practice.

Lifestyle and Environmental Approaches for the Primary Prevention of Hepatocellular Carcinoma

Patients with chronic liver disease are at increased risk of developing hepatocellular carcinoma (HCC). Most patients diagnosed with HCC have limited treatment options and a poor overall prognosis, with a 5-year survival less than 15%. Preventing the development of HCC represents the most important strategy. However, current guidelines lack specific recommendations for primary prevention. Lifestyle factors may be central in the pathogenesis of HCC, and primary prevention strategies focused on lifestyle modification could represent an important approach to the prevention of HCC. Both experimental and epidemiologic studies have identified promising chemopreventive agents for the primary prevention of HCC.

Statin Use and the Risk of Hepatocellular Carcinoma: A Meta-Analysis of Observational Studies

Background and Aims: Statins are the first-line medication to treating hypercholesterolemia. Several studies have investigated the impact of statins on the risk of hepatocellular carcinoma (HCC). However, the extent to which statins may prevent HCC remains uncertain. Therefore, we performed a meta-analysis of relevant studies to quantify the magnitude of the association between statins use and the risk of HCC. Methods: A systematic literature search of PubMed, EMBASE, Google Scholar, Web of Science, and Scopus was performed for studies published between January 1, 1990, and September 1, 2019, with no restriction of language. Two reviewers independently evaluated the literature and included observational and experimental studies that reported the association between statin use and HCC risk. The random-effect model was used to calculate the overall risk ratio (RR) with a 95% confidence interval (CI), and the heterogeneity among the studies was assessed using the Q statistic and I² statistic. The Newcastle Ottawa Scale (NOS) was also used to evaluate the quality of the included studies. Results: A total of 24 studies with 59,073 HCC patients was identified. Statin use was associated with a reduced risk of HCC development (RR: 0.54, 95% CI: 0.47–0.61, I² = 84.39%) compared with nonusers. Moreover, the rate of HCC reduction was also significant among patients with diabetes (RR: 0.44, 95% CI: 0.28–0.70), liver cirrhosis (RR: 0.36, 95% CI: 0.30–0.42), and antiviral therapy (RR: 0.21, 95% CI: 0.08–0.59) compared with nonusers. Conclusion: This study serves as additional evidence supporting the beneficial inhibitory effect of statins on HCC incidence. The subgroup analyses of this study also highlight that statins are significantly associated with a reduced risk of HCC and may help to direct future prevention efforts. Additional large clinical studies are needed to determine whether statins are associated with a lower risk of HCC.

The Burden of Hepatocellular Carcinoma in Non-Alcoholic Fatty Liver Disease: Screening Issue and Future Perspectives

In recent decades, non-alcoholic fatty liver disease (NAFLD) has become the most common liver disease in the Western world, and the occurrence of its complications, such as hepatocellular carcinoma (HCC), has rapidly increased. Obesity and diabetes are considered not only the main triggers for the development of the disease, but also two independent risk factors for HCC. Single nucleotide polymorphisms (such as PNPLA3, TM6SF2 and MBOAT7) are related to the susceptibility to the development of HCC and its progression. Therefore, an appropriate follow-up of these patients is needed for the early diagnosis and treatment of HCC. To date, international guidelines recommend the use of ultrasonography with or without alpha-fetoprotein (AFP) in patients with advanced fibrosis. Furthermore, the use of non-invasive tools could represent a strategy to implement surveillance performance. In this review, we analyzed the main risk factors of NAFLD-related HCC, the validated screening methods and the future perspectives.

Generic chemoprevention of hepatocellular carcinoma

Chronic fibrotic liver disease caused by viral or metabolic etiologies is a high-risk condition for developing hepatocellular carcinoma (HCC). Even after curative treatment of early-stage HCC tumor, the carcinogenic microenvironment persists in the remnant diseased liver and supports the development of de novo HCC tumors (de novo HCC recurrence). Therefore, prevention of HCC development in patients at risk of not only first-primary but also second-primary HCC tumors is theoretically the most impactful strategy to improve patient prognosis. However, no such therapy has been established to date. One major challenge is the identification of clinically relevant targets that can be achieved by utilizing the reverse-engineering strategy of chemoprevention discovery, which integrates omics information from clinical cohorts with completed follow-up for cancer development. Clinical and experimental studies have suggested etiology-specific and generic candidate HCC chemoprevention strategies, including statins, antidiabetic drugs, selective molecular targeted agents, and dietary and nutritional substances. Clinical testing of the candidate compounds can be cost-effectively performed by combining it with HCC risk biomarker evaluation to specify the target patient population most likely to benefit from the therapy. Nontoxic, generic agents will have broad clinical applicability across the diverse HCC etiologies and clinical contexts and are expected to substantially improve the still dismal prognosis of HCC.

Risk factors and prevention of hepatocellular carcinoma in the era of precision medicine

Patients who develop chronic fibrotic liver disease, caused by viral or metabolic aetiologies, are at a high risk of developing hepatocellular carcinoma (HCC). Even after complete HCC tumour resection or ablation, the carcinogenic tissue microenvironment in the remnant liver can give rise to recurrent de novo HCC tumours, which progress into incurable, advanced-stage disease in most patients. Thus, early detection and prevention of HCC development is, in principle, the most impactful strategy to improve patient prognosis. However, a "one-size-fits-all" approach to HCC screening for early tumour detection, as recommended by clinical practice guidelines, is utilised in less than 20% of the target population, and the performance of screening modalities, including ultrasound and alpha-fetoprotein, is suboptimal. Furthermore, optimal screening strategies for emerging at-risk patient populations, such as those with chronic hepatitis C after viral cure, or those with non-cirrhotic, non-alcoholic fatty liver disease remain controversial. New HCC biomarkers and imaging modalities may improve the sensitivity and specificity of HCC detection. Clinical and molecular HCC risk scores will enable precise HCC risk prediction followed by tailoured HCC screening of individual patients, maximising cost-effectiveness and optimising allocation of limited medical resources. Several aetiology-specific and generic HCC chemoprevention strategies are evolving. Epidemiological and experimental studies have identified candidate chemoprevention targets and therapies, including statins, anti-diabetic drugs, and selective molecular targeted agents, although their clinical testing has been limited by the lengthy process of cancer development that requires long-term, costly studies. Individual HCC risk prediction is expected to overcome the challenge by enabling personalised chemoprevention, targeting high-risk patients for precision HCC prevention and substantially improving the dismal prognosis of HCC.

Combined pitavastatin and dacarbazine treatment activates apoptosis and autophagy resulting in synergistic cytotoxicity in melanoma cells

Melanoma is an aggressive skin cancer and its incidence is increasing faster than any other type of cancer. Whilst dacarbazine (DTIC) is the standard chemotherapy for metastatic melanoma, it has limited success. Statins, including pitavastatin, have been demonstrated to have a range of anti-cancer effects in a number of human cancer cell lines. The present study therefore explored the anti-cancer activity of combined DTIC and pitavastatin in A375 and WM115 human melanoma cells. Cell survival assays demonstrated that combined DTIC and pitavastatin treatment resulted in synergistic cell death. Cell cycle analyses further revealed that this combined treatment resulted in a G1 cell cycle arrest, as well as a sub-G1 population, indicative of apoptosis. Activation of apoptosis was confirmed by Annexin V-fluorescein isothiocyanate/propidium iodide double-staining and an increase in the levels of active caspase 3 and cleaved poly (ADP-ribose) polymerase. Furthermore, it was demonstrated that apoptosis occurs through the intrinsic pathway, evident from the release of cytochrome c. Finally, combined DTIC and pitavastatin treatment was demonstrated to also activate autophagy as part of a cell death mechanism. The present study provides novel evidence to suggest that the combined treatment of DTIC and pitavastatin may be effective in the treatment of melanoma.

Statin (3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor)-based therapy for hepatitis C virus (HCV) infection-related diseases in the era of direct-acting antiviral agents

Recent improvements have been made in the treatment of hepatitis C virus (HCV) infection with the introduction of direct-acting antiviral agents (DAAs). However, despite successful viral clearance, many patients continue to have HCV-related disease progression. Therefore, new treatments must be developed to achieve viral clearance and prevent the risk of HCV-related diseases. In particular, the use of pitavastatin together with DAAs may improve the antiviral efficacy as well as decrease the progression of liver fibrosis and the incidence of HCV-related hepatocellular carcinoma. To investigate the management methods for HCV-related diseases using pitavastatin and DAAs, clinical trials should be undertaken. However, concerns have been raised about potential drug interactions between statins and DAAs. Therefore, pre-clinical trials using a replicon system, human hepatocyte-like cells, human neurons and human cardiomyocytes from human-induced pluripotent stem cells should be conducted. Based on these pre-clinical trials, an optimal direct-acting antiviral agent could be selected for combination with pitavastatin and DAAs. Following the pre-clinical trial, the combination of pitavastatin and the optimal direct-acting antiviral agent should be compared to other combinations of DAAs ( e.g., sofosbuvir and velpatasvir) according to the antiviral effect on HCV infection, HCV-related diseases and cost-effectiveness.

Chemosensitization of HepG2 cells by suppression of NF-κB/p65 gene transcription with specific-siRNA

AIM

To investigate small interfering RNA (siRNA)-mediated inhibition of nuclear factor-kappa B (NF-κB) activation and multidrug-resistant (MDR) phenotype formation in human HepG2 cells.

METHODS

Total RNA was extracted from human HepG2 or LO2 cells. NF-κB/p65 mRNA was amplified by nested reverse transcription polymerase chain reaction and confirmed by sequencing. NF-κB/p65 was analyzed by immunohistochemistry. Specific-siRNA was transfected to HepG2 cells to knock down NF-κB/p65 expression. The effects on cell proliferation, survival, and apoptosis were assessed, and the level of NF-κB/p65 or P-glycoprotein (P-gp) was quantitatively analyzed by enzyme-linked immunosorbent assay.

RESULTS

HepG2 cells express NF-κB/p65 and express relatively less phosphorylated p65 (P-p65) and little P-gp. After treatment of HepG2 cells with different doses of doxorubicin, the expression of NF-κB/p65, P-p65, and especially P-gp were dose-dependently upregulated. After HepG2 cells were transfected with NF-κB/p65 siRNA (100 nmol/L), the expression of NF-κB/p65, P-p65, and P-gp were downregulated significantly and dose-dependently. The viability of HepG2 cells was decreased to 23% in the combination NF-κB/p65 siRNA (100 nmol/L) and doxorubicin (0.5 μmol/L) group and 47% in the doxorubicin (0.5 μmol/L) group (t = 7.043, P < 0.001).

CONCLUSION

Knockdown of NF-κB/p65 with siRNA is an effective strategy for inhibiting HepG2 cell growth by downregulating P-gp expression associated chemosensitization and apoptosis induction.

Pitavastatin suppressed liver cancer cells in vitro and in vivo

Pitavastatin classically functions as a blood cholesterol-lowering drug. Previously, it was discovered with antiglioma stem cell properties through drug screening. However, whether it can be used for liver cancer cell therapy has never been reported. In this study, the cell viability and colony formation assay were utilized to analyze the cytotoxicity of pitavastatin on liver cancer cells. The cell cycle alteration was checked after pitavastatin treatment. Apoptosis-related protein expression and the effect of caspase inhibitor were also checked. The in vivo inhibitory effect of pitavastatin on the growth of liver tumor was also tested. It was found that pitavastatin inhibited growth and colony formation of liver cancer Huh-7 cells and SMMC7721 cells. It induced arrest of liver cancer cells at the G1 phase. Increased proportion of sub-G1 cells was observed after pitavastatin treatment. Pitavastatin promoted caspase-9 cleavage and caspase-3 cleavage in liver cancer cells. Caspase inhibitor Z-VAD-FMK reversed the cleavage of cytotoxic effect of pitavastatin. Moreover, pitavastatin decreased the tumor growth and improved the survival of tumor-bearing mice. This study suggested the antiliver cancer effect of the old drug pitavastatin. It may be developed as a drug for liver cancer therapy.

Chemosensitization of HepG2 cells by suppression of NF-κB/p65 gene transcription with specific-siRNA

AIM

To investigate small interfering RNA (siRNA)-mediated inhibition of nuclear factor-kappa B (NF-κB) activation and multidrug-resistant (MDR) phenotype formation in human HepG2 cells.

METHODS

Total RNA was extracted from human HepG2 or LO2 cells. NF-κB/p65 mRNA was amplified by nested reverse transcription polymerase chain reaction and confirmed by sequencing. NF-κB/p65 was analyzed by immunohistochemistry. Specific-siRNA was transfected to HepG2 cells to knock down NF-κB/p65 expression. The effects on cell proliferation, survival, and apoptosis were assessed, and the level of NF-κB/p65 or P-glycoprotein (P-gp) was quantitatively analyzed by enzyme-linked immunosorbent assay.

RESULTS

HepG2 cells express NF-κB/p65 and express relatively less phosphorylated p65 (P-p65) and little P-gp. After treatment of HepG2 cells with different doses of doxorubicin, the expression of NF-κB/p65, P-p65, and especially P-gp were dose-dependently upregulated. After HepG2 cells were transfected with NF-κB/p65 siRNA (100 nmol/L), the expression of NF-κB/p65, P-p65, and P-gp were downregulated significantly and dose-dependently. The viability of HepG2 cells was decreased to 23% in the combination NF-κB/p65 siRNA (100 nmol/L) and doxorubicin (0.5 μmol/L) group and 47% in the doxorubicin (0.5 μmol/L) group (t = 7.043, P < 0.001).

CONCLUSION

Knockdown of NF-κB/p65 with siRNA is an effective strategy for inhibiting HepG2 cell growth by downregulating P-gp expression associated chemosensitization and apoptosis induction.

Pitavastatin suppresses diethylnitrosamine-induced liver preneoplasms in male C57BL/KsJ-db/db obese mice

BACKGROUND

Obesity and related metabolic abnormalities, including inflammation and lipid accumulation in the liver, play a role in liver carcinogenesis. Adipocytokine imbalances, such as decreased serum adiponectin levels, are also involved in obesity-related liver tumorigenesis. In the present study, we examined the effects of pitavastatin - a drug used for the treatment of hyperlipidemia - on the development of diethylnitrosamine (DEN)-induced liver preneoplastic lesions in C57BL/KsJ-db/db (db/db) obese mice.

METHODS

Male db/db mice were administered tap water containing 40 ppm DEN for 2 weeks and were subsequently fed a diet containing 1 ppm or 10 ppm pitavastatin for 14 weeks.

RESULTS

At sacrifice, feeding with 10 ppm pitavastatin significantly inhibited the development of hepatic premalignant lesions, foci of cellular alteration, as compared to that in the untreated group by inducing apoptosis, but inhibiting cell proliferation. Pitavastatin improved liver steatosis and activated the AMPK-α protein in the liver. It also decreased free fatty acid and aminotransferases levels, while increasing adiponectin levels in the serum. The serum levels of tumor necrosis factor (TNF)-α and the expression of TNF-α and interleukin-6 mRNAs in the liver were decreased by pitavastatin treatment, suggesting attenuation of the chronic inflammation induced by excess fat deposition.

CONCLUSIONS

Pitavastatin is effective in inhibiting the early phase of obesity-related liver tumorigenesis and, therefore, may be useful in the chemoprevention of liver cancer in obese individuals.

Suppression of human hepatoma (HepG2) cell growth by nuclear factor-kappaB/p65 specific siRNA

Nuclear factor-kappaB (NF-κB) is a transcription factor and antagonist of apoptosis during liver regeneration and closely related to the formation and development of hepatocellular carcinoma. In the present study, we investigated the effect of small interference RNA (siRNA)-mediated inhibition of NF-κB on growth of human hepatoma (HepG2) cells. Our data indicated that the expression of NF-κB/p65 mRNA was significantly higher in the HepG2 cells than that in the normal liver (LO2) cells before transfection, and the expression of NF-κB/p65 in the HepG2 cells with NF-κB/p65 siRNA (100 nMol/L) transfection at 72 h was reduced at the levels of mRNA (93%) and protein (62%) using real-time reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assay, and Western blotting. Interestingly, the apoptosis index of the HepG2 cells increased up to 85%, detected by Annexin V-fluorescein isothiocyanate, suggesting that NF-κB is overexpressed in hepatoma cells and can be inhibited by NF-κB/p65 siRNA through the apoptotic mechanism. Thus, we conclude that NF-κB is a potential molecular target for HCC gene therapy.

Suppression of human hepatoma (HepG2) cell growth by nuclear factor-kappaB/p65 specific siRNA

Nuclear factor-kappaB (NF-κB) is a transcription factor and antagonist of apoptosis during liver regeneration and closely related to the formation and development of hepatocellular carcinoma. In the present study, we investigated the effect of small interference RNA (siRNA)-mediated inhibition of NF-κB on growth of human hepatoma (HepG2) cells. Our data indicated that the expression of NF-κB/p65 mRNA was significantly higher in the HepG2 cells than that in the normal liver (LO2) cells before transfection, and the expression of NF-κB/p65 in the HepG2 cells with NF-κB/p65 siRNA (100 nMol/L) transfection at 72 h was reduced at the levels of mRNA (93%) and protein (62%) using real-time reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assay, and Western blotting. Interestingly, the apoptosis index of the HepG2 cells increased up to 85%, detected by Annexin V-fluorescein isothiocyanate, suggesting that NF-κB is overexpressed in hepatoma cells and can be inhibited by NF-κB/p65 siRNA through the apoptotic mechanism. Thus, we conclude that NF-κB is a potential molecular target for HCC gene therapy.

Silencing of TNF-alpha receptors coordinately suppresses TNF-alpha expression through NF-kappaB activation blockade in THP-1 macrophage

Persistently elevated level of TNF-alpha has been implicated in several inflammatory disorders, however, its autocrine production through TNF-alpha receptors signaling is poorly understood. Here we report that simultaneous silencing of TNF-receptors, R1 and R2 by DNAzyme or siRNA suppressed TNF-alpha expression more efficiently than silencing them individually in lipopolysaccharides (LPS) stimulated THP-1 macrophages. Co-silencing of TNF-receptors also inhibited TNF-alpha induced NF-kappaB activation to a higher extent. It was further observed that NF-kappaB inhibitor but not c-Jun N-terminal kinase inhibitor (SP600125) suppressed TNF-alpha expression. All these results suggest that TNF-alpha expression is regulated by synergistic signaling of TNF receptors through downstream NF-kappaB activation.

A lipophilic statin, pitavastatin, suppresses inflammation-associated mouse colon carcinogenesis

3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors are known to modulate carcinogenesis. In this study, we investigated whether a lipophilic HMG-CoA reductase inhibitor pitavastatin suppresses inflammation-related mouse colon carcinogenesis. Male CD-1 (ICR) mice were initiated with a single intraperitoneal injection of azoxymethane (AOM, 10 mg/kg body weight) and promoted by 2% (w/v) dextran sodium sulfate (DSS) in drinking water for 7 days. The experimental diets containing pitavastatin at 2 dose levels (1 and 10 ppm) were fed to male CD-1 (ICR) mice for 17 weeks, staring 1 week after the cessation of DSS exposure. The effects of dietary pitavastatin on colonic tumor development were assessed at Weeks 5, 10 and 20. Feeding with pitavastatin at both doses significantly inhibited the multiplicity of colonic adenocarcinoma at Week 20. Furthermore, the treatment significantly lowered the positive rates of proliferating cell nuclear antigen and increased the apoptotic index in the colonic epithelial malignancies. The treatment also reduced nitrotyrosine-positivity in the colonic mucosa. Our findings thus show that pitavastatin is effective in inhibiting colitis-related colon carcinogenesis through modulation of mucosal inflammation, oxidative/nitrosative stress, and cell proliferation.

Traditional Chinese herbal medicines for treatment of liver fibrosis and cancer: from laboratory discovery to clinical evaluation

Liver disease afflicts over 10% of the world population. This includes chronic hepatitis, alcoholic steatosis, fibrosis, cirrhosis and hepatocellular carcinoma (HCC), which are the most health-threatening conditions drawing considerable attention from medical professionals and scientists. Patients with alcoholism or viral hepatitis are much more likely to have liver cell damage and cirrhosis, and some may eventually develop HCC, which is unfortunately, and very often, a fatal malignancy without cure. While liver surgery is not suitable in many of the HCC cases, patients are mostly given palliative support cares or transarterial chemoembolization or systemic chemotherapies. However, HCC is well known to be a highly chemoresistant tumour, and the response rate is <10-20%. To this end, alternative medicines are being actively sought from other sources with hopes to halt the disease's progression or even eliminate the tumours. Traditional Chinese herbal medicine has begun to gain popularity worldwide for promoting healthcare as well as disease prevention, and been used as conventional or complementary medicines for both treatable and incurable diseases in Asia and the West. In this article, we discuss the laboratory findings and clinical trial studies of Chinese herbal medicines (particularly small molecule compounds) for the treatment of liver disease ranging from fibrosis to liver cancer.