New insights into the role of vitamin D in hepatocellular carcinoma

Insights into the role of vitamin D in targeting the culprits of non-alcoholic fatty liver disease

Vitamin D (VD) is a secosteroid hormone that is renowned for its crucial role in phospho-calcium homeostasis upon binding to the nuclear vitamin D receptor (VDR). Over and above, the pleiotropic immunomodulatory, anti-inflammatory, and metabolic roles VD plays in different disease settings started to surface in the past few decades. On the other hand, a growing body of evidence suggests a correlation between non-alcoholic fatty liver disease (NAFLD) and its progressive inflammatory form non-alcoholic steatohepatitis (NASH) with vitamin D deficiency (VDD) owing to the former's ingrained link with obesity and metabolic syndrome. Accordingly, a better understanding of the contribution of disrupted VDR signalling to NAFLD incidence and progression would provide further insights into its diagnosis, treatment modalities, and prognosis. This is especially significant as, hitherto, no drug for NAFLD has been approved. This review, therefore, sought to set forth the likely contribution of VDR signalling in NAFLD and how it might influence its multiple drivers.

Bone Densities Assessed by Hounsfield Units at L5 in Computed Tomography Image Independently Predict Hepatocellular Carcinoma Development in Cirrhotic Patients

A previous study identified that bone density (BD) assessed by Hounsfield unit (HU) at T12 in computed tomography (CT) image was a predictor for hepatocellular carcinoma (HCC) development in cirrhotic patients. Here, we conducted a verification study, where clinical variables together with BDs (assessed from three different bone areas: T12, L5, and femur trochanter) were assessed for their predictive values for time-to-HCC development in cirrhotic patients. Univariate Cox proportional hazard analysis showed that age (p = 0.017), T12 BD (p = 0.013) and L5 BD (p = 0.005), but not femur BD, were significant predictors. Multivariate analysis revealed that L5 BD was the only independent factor associated with time-to-HCC development (adjusted p = 0.007). Kaplan-Meier analysis confirmed that BD which was lower than median HU was associated with a shorter time-to-HCC development for both T12 BD and L5 BD (p = 0.001 each). Longitudinal follow-ups for BDs in HCC patients having received serial CT imaging studies unveiled a significantly rapid reduction in BD, right before HCC was diagnosed (p = 0.025 when compared with the average BD reduction rate). In conclusion, BD assessed by HU at L5 was an independent predictor for HCC development in cirrhotic patients. Rapid BD reduction during CT scan follow-ups could serve as a warning sign for HCC development.

Potential anti-hepatocellular carcinoma properties and mechanisms of action of clerodane diterpenes isolated from Polyalthia longifolia seeds

Diterpenes are secondary metabolites that have attracted much attention due to their potential biological activities including anti-cancer potential. The aim of the current study is to assess the anticancer potential of the six known clerodane diterpenes (1–6) isolated from Polyalthia longifolia seeds and their underlying molecular mechanisms. These compounds were evaluated for their cytotoxicity in vitro by using MTT assays. The “two-phase model” with NDEA and PB ad libitum was used for induction of HCC and sorafenib was used as the standard drug. Prophylactic studies were carried out for compounds 4/6 at both low (5 mg/kg b.w) and high (10 mg/kg b.w) doses. Based on the MTT assay results, the two best compounds, 4 and 6, were selected for in vivo studies. The results showed that treatment with compound 4/6 significantly restored the changes in biochemical parameters and liver morphology observed in (NDEA + PB)-induced HCC rats. Additionally, the docking studies showed that compound 4/6 interacted with several key proteins such as MDM2, TNF-α, FAK, thereby inhibiting these proteins and reversing the negative impacts of NDEA. In conclusion, our results suggested that compounds 4 and 6 are potential therapeutic agents for HCC, mostly due to their ability to control typical cancer pathways.

Carboranes as unique pharmacophores in antitumor medicinal chemistry

Carborane is a carbon-boron molecular cluster that can be viewed as a 3D analog of benzene. It features special physical and chemical properties, and thus has the potential to serve as a new type of pharmacophore for drug design and discovery. Based on the relative positions of two cage carbons, icosahedral closo-carboranes can be classified into three isomers, ortho-carborane (o-carborane, 1,2-C2B10H12), meta-carborane (m-carborane, 1,7-C2B10H12), and para-carborane (p-carborane, 1,12-C2B10H12), and all of them can be deboronated to generate their nido- forms. Cage compound carborane and its derivatives have been demonstrated as useful chemical entities in antitumor medicinal chemistry. The applications of carboranes and their derivatives in the field of antitumor research mainly include boron neutron capture therapy (BNCT), as BNCT/photodynamic therapy dual sensitizers, and as anticancer ligands. This review summarizes the research progress on carboranes achieved up to October 2021, with particular emphasis on signaling transduction pathways, chemical structures, and mechanistic considerations of using carboranes.

Cathelicidin hCAP18/LL-37 promotes cell proliferation and suppresses antitumor activity of 1,25(OH)2D3 in hepatocellular carcinoma

Cathelicidin hCAP18/LL-37 can resist infection from various pathogens and is an essential component of the human immune system. Accumulating evidence has indicated that hCAP18/LL-37 plays a tissue-specific role in human cancer. However, its function in hepatocellular carcinoma (HCC) is poorly understood. The present study investigated the effects of hCAP18/LL-37 on HCC in vitro and in vivo. Results showed that hCAP18/LL-37 overexpression significantly promoted the proliferation of cultured HCC cells and the growth of PLC/PRF-5 xenograft tumor. Transcriptome sequencing analyses revealed that the PI3K/Akt pathway was the most significant upregulated pathway induced by LL-37 overexpression. Further analysis demonstrated that hCAP18/LL-37 stimulated the phosphorylation of EGFR/HER2 and activated the PI3K/Akt pathway in HCC cells. Furthermore, stronger EGFR/HER2/Akt signals were observed in the PLC/PRF-5^LL-37 xenograft tumor. Interestingly, even though the expression of hCAP18/LL-37 was significantly downregulated in HCC cells and tumors, 1,25(OH)₂D₃ treatment significantly upregulated the hCAP18/LL-37 level both in HCC cells and xenograft tumors. Moreover, 1,25(OH)₂D₃ together with si-LL-37 significantly enhanced the antitumor activity of 1,25(OH)₂D₃ in the PLC/PRF-5 xenograft tumor. Collectively, these data suggest that hCAP18/LL-37 promotes HCC cells proliferation through stimulation of the EGFR/HER2/Akt signals and appears to suppress the antitumor activity of 1,25(OH)₂D₃ in HCC xenograft tumor. This implies that hCAP18/LL-37 may be an important target when aiming to improve the antitumor activity of 1,25(OH)₂D₃ supplementation therapy in HCC.

Vitamin D3 supplementation alleviates chemically-induced cirrhosis-associated hepatocarcinogenesis

Vitamin D₃ (VD₃) deficiency has been associated with increased risk for cirrhosis and hepatocellular carcinoma, a highly incident malignant neoplasia worldwide. On the other hand, VD₃ supplementation has shown some beneficial effects in clinical studies and rodent models of chronic liver disease. However, preventive effects of dietary VD₃ supplementation in cirrhosis-associated hepatocarcinogenesis is still unknow. To investigate this purpose, male Wistar rats submitted to a combined diethylnitrosamine- and thioacetamide-induced model were concomitantly supplemented with VD₃ (5,000 and 10,000 IU/kg diet) for 25 weeks. Liver samples were collected for histological, biochemical and molecular analysis. Serum samples were used to measure 25-hydroxyvitamin D [25(OH)D] and alanine aminotransferase levels. Both VD₃ interventions decreased hepatic collagen deposition and pro-inflammatory p65 protein levels, while increased hepatic antioxidant catalase and glutathione peroxidase activities and serum 25(OH)D, without a clear dose-response effect. Nonetheless, only the highest concentration of VD₃ increased hepatic protein levels of VD receptor, while decreased the number of large preneoplastic glutathione-S-transferase- (>0.5 mm²) and keratin 8/18-positive lesions, as well the multiplicity of hepatocellular adenomas. Moreover, this intervention increased hepatic antioxidant Nrf2 protein levels and glutathione-S-transferase activity. In summary, dietary VD₃ supplementation - in special the highest intervention - showed antifibrotic and antineoplastic properties in chemically-induced cirrhosis-associated hepatocarcinogenesis. The positive modulation of Nrf2 antioxidant axis may be mechanistically involved with these beneficial effects, and may guide future clinical studies.

NAFLD and Vitamin D: Evidence for Intersection of MicroRNA Regulated Pathways

Non-alcoholic fatty liver disease (NAFLD) is now the most common cause of chronic liver disease, worldwide. The molecular pathogenesis of NAFLD is complex, involving numerous signalling molecules including microRNAs (miRNAs). Dysregulation of miRNA expression is associated with hepatic inflammation, fibrosis and hepatocellular carcinoma. Although miRNAs are also critical to the cellular response to vitamin D, mediating regulation of the vitamin D receptor (VDR) and vitamin D’s anticancer effects, a role for vitamin D regulated miRNAs in NAFLD pathogenesis has been relatively unexplored. Therefore, this review aimed to critically assess the evidence for a potential subset of miRNAs that are both dysregulated in NAFLD and modulated by vitamin D. Comprehensive review of 89 human studies identified 25 miRNAs found dysregulated in more than one NAFLD study. In contrast, only 17 studies, including a protocol for a trial in NAFLD, had examined miRNAs in relation to vitamin D status, response to supplementation, or vitamin D in the context of the liver. This paper summarises these data and reviews the biological roles of six miRNAs (miR-21, miR-30, miR-34, miR-122, miR-146, miR-200) found dysregulated in multiple independent NAFLD studies. While modulation of miRNAs by vitamin D has been understudied, integrating the data suggests seven vitamin D modulated miRNAs (miR-27, miR-125, miR-155, miR-192, miR-223, miR-375, miR-378) potentially relevant to NAFLD pathogenesis. Our summary tables provide a significant resource to underpin future hypothesis-driven research, and we conclude that the measurement of serum and hepatic miRNAs in response to vitamin D supplementation in larger trials is warranted.

Regulation of TREM1-Mediated Inflammation in Hepatocellular Carcinoma Cells

Hepatocellular carcinoma (HCC), accounting for more than 90% of cases of primary liver cancer, is the third most common cause of cancer-related death worldwide. Chronic inflammation precedes the development of cirrhosis and HCC. TREM (triggering receptor expressed on myeloid cell)-1 is an inflammatory marker and amplifier of inflammation that signals through PI3K and ERK1/2 to activate transcription factors, resulting in increased secretion of pro-inflammatory cytokines, causing chronic inflammation and predisposing the liver to carcinogenesis. Thus, targeting TREM-1 in HCC might be a potential therapeutic target. A low level of vitamin D has been associated with chronic inflammation and poor prognosis in HCC. Thus, we evaluated the effect of vitamin D on TREM-1 expression in the HCC cell line. Additionally, the effects of high mobility group box-1, lipopolysaccharide, and transcription factor PU.1 on the expression of TREM-1 in normal liver cells and HCC cells have been investigated in the presence and absence of vitamin D. The results showed increased expression of TREM-1 in HCC cells and with IL-6, TNF-α, LPS, and rHMGB-1 and decreased expression with calcitriol. Calcitriol also attenuated the effect of IL-6, TNF-α, LPS, and rHMGB-1 on TREM-1. Calcitriol treatment attenuated the proliferation, migration, and invasion of HCC cells. These results (in vitro) provide molecular and biochemical evidence that calcitriol significantly attenuates the expression of mediators of inflammation, and thus might be used therapeutically together with conventional treatment to delay the progression of HCC. Additionally, the negative regulation of TREM-1 by PU.1 suggests PU.1 as a potential therapeutic target.

Cross-sectional observational study - Investigation of vitamin D concentration in Caucasian cancer patients. what is the adequate dose of vitamin D for these patients?

BACKGROUND & AIMS

Vitamin D impairs tumour-related transformation and supports the anticancer function of the immune system. Currently, there are no guidelines on vitamin D supplementation devoted solely to cancer patients. The primary objective of the study was to evaluate the frequency of vitamin D deficiency in Caucasian cancer patients and to characterize the clinical factors that predispose individuals to decreased vitamin D concentration. Secondly, the study aimed to estimate the dose of vitamin D supplementation that would prevent deficiencies in patients with cancer.

METHODS

In the presented cross-sectional study the population consisted of 500 consecutive Caucasian patients with a diagnosis of neoplastic disease, some of which declared long-term vitamin D supplementation in various doses. Serum vitamin D concentration was measured once in all patients and clinical data were obtained from the hospital database. The frequencies of vitamin D deficiency were compared to certain clinical variables by appropriate statistical tests. The dose of vitamin D substitution in cancer patients was estimated using the receiver operating characteristic (ROC) curve.

RESULTS

Vitamin D deficiency was diagnosed in 66.8% of patients with cancer and even in 31.6% who declared vitamin D supplementation. Older age, male gender, diagnosis of head and neck cancer or squamous cell carcinoma and body mass loss were identified as factors that predispose to vitamin D deficiency. The dose of vitamin D that would prevent deficiency in Caucasian patients with cancer was set at 2250 IU daily.

CONCLUSIONS

Vitamin D deficiency was very common in Caucasian patients with cancer, even in terms of vitamin D supplementation. The greatest predisposition was related to elder age, male gender, diagnosis of head and neck or squamous cell carcinoma and body mass loss. The dose of vitamin D supplementation in cancer patients should probably be higher than in the general population.

Low serum vitamin D level associated with incident advanced liver disease in the general population - a prospective study

BACKGROUND

Vitamin D deficiency is a common finding in chronic liver disease. It has also been linked to the pathogenesis of non-alcoholic fatty liver disease, hepatic fibrogenesis, decompensation and hepatocellular carcinoma.

AIMS

We analyzed whether serum vitamin D is associated with incident advanced liver disease in the general population.

METHODS

Serum 25-hydroxyvitamin D was measured in 13807 individuals participating in the Finnish population-based health examination surveys FINRISK 1997 and Health 2000. Data were linked with incident advanced liver disease (hospitalization, cancer or death related to liver disease). During a follow-up of 201444 person-years 148 severe liver events occurred. Analyses were performed using multivariable Cox regression analyses.

RESULTS

Vitamin D level associated with incident advanced liver disease with the hazard ratio of 0.972 (95% confidence interval 0.943-0.976, p < .001), when adjusted for age, sex, blood sampling season and stratified by cohort.The association remained robust and significant in multiple different adjustment models adjusting sequentially for 22 potential confounders.

CONCLUSION

Low vitamin D level is linked to incident advanced liver disease at population level.

Association of circulating 25-Hydroxyvitamin D and its related genetic variations with hepatocellular carcinoma incidence and survival

Background

Vitamin D plays a key role of anti-cancer process, however, the association of vitamin D level and its related genetic variants with hepatocellular carcinoma (HCC) risk and prognosis is not fully understood.

Methods

We enrolled 100 HCC patients and 8,242 health controls from Sir Run Run Shaw Hospital. Logistic regression model was used to calculate the odds ratio (OR) and 95% CI for HCC risk according to serum 25(OH)D concentration. Mendelian randomization (MR) approach was also conducted to validate the potential causal association of 25(OH)D with HCC risk. Hazard ratio (HR) for the association of SNPs with overall survival and disease-free survival was assessed by multivariate Cox hazard proportional regression model.

Results

Plasma 25(OH)D level greater than 20 ng/mL increased HCC risk (OR =7.56, 95% CI: 4.58–12.50). MR analysis also showed a slightly increased risk of HCC by 25(OH)D increasing, yet did not reach statistical significance (OR =1.03, 95% CI: 0.31–3.47). With regard to HCC survival, compared to patients with rs8018720 GG genotype, patients with rs8018720 CC/CG genotype had a longer disease-free survival time (HR =0.39, 95% CI: 0.18–0.81). There was an interaction between rs12785878 and 25(OH)D level in continuous scale for HCC mortality. An interaction between rs12785878 and dichotomized 25(OH)D concentration for disease-free survival of HCC patients was also confirmed.

Conclusions

There is hazard of circulating 25(OH)D concentration for HCC occurrence, but protective effect of the interaction between circulating 25(OH)D concentration and its related genetic variation for HCC prognosis. Further study is needed to confirm or refute these findings in a larger population.

Serum Vitamin D Levels and Risk of Liver Cancer: A Systematic Review and Dose-Response Meta-Analysis of Cohort Studies

Data regarding the relationship between serum vitamin D levels and the risk of liver cancer are conflicting. Therefore, we performed a systematic review and dose-response meta-analysis of all available data of cohort studies on the association of 25-OH-vitamin-D levels with the risk of hepatocellular carcinoma. We conducted a systematic search in PubMed-MEDLINE, Scopus, Cochrane and Web of Science databases for prospective observational studies conducted on the general population from inception to May 2019. Six studies provided data from 6357 participants. According to the pooled HR, the subjects with the highest serum concentrations of vitamin D had a 47% lower risk of liver cancer vs. the subjects with the lowest serum concentrations of vitamin D (pooled HR: 0.53, 95% CI: 0.41-0.68; P < 0.001). There was no significant heterogeneity among the studies (P = 0.431, I² = 0.0). The pooled HR from the random-effects dose-response model indicated an indirect significant linear association between vitamin D and the risk of liver cancer (coef = -0.017, P < 0.001). However, there was no significant nonlinear dose-response association between serum vitamin D and the risk of liver cancer (coef = -0.0001, P = 0.342). The evidence from this meta-analysis suggests that there may be an inverse relationship between serum vitamin D levels and the risk of liver cancer.

Vitamin D Signaling in Inflammation and Cancer: Molecular Mechanisms and Therapeutic Implications

Vitamin D and its active metabolites are important nutrients for human skeletal health. UV irradiation of skin converts 7-dehydrocholesterol into vitamin D3, which metabolized in the liver and kidneys into its active form, 1α,25-dihydroxyvitamin D3. Apart from its classical role in calcium and phosphate regulation, scientists have shown that the vitamin D receptor is expressed in almost all tissues of the body, hence it has numerous biological effects. These includes fetal and adult homeostatic functions in development and differentiation of metabolic, epidermal, endocrine, neurological and immunological systems of the body. Moreover, the expression of vitamin D receptor in the majority of immune cells and the ability of these cells to actively metabolize 25(OH)D3 into its active form 1,25(OH)₂D3 reinforces the important role of vitamin D signaling in maintaining a healthy immune system. In addition, several studies have showed that vitamin D has important regulatory roles of mechanisms controlling proliferation, differentiation and growth. The administration of vitamin D analogues or the active metabolite of vitamin D activates apoptotic pathways, has antiproliferative effects and inhibits angiogenesis. This review aims to provide an up-to-date overview on the effects of vitamin D and its receptor (VDR) in regulating inflammation, different cell death modalities and cancer. It also aims to investigate the possible therapeutic benefits of vitamin D and its analogues as anticancer agents.

Morphomic Signatures Derived from Computed Tomography Predict Hepatocellular Carcinoma Occurrence in Cirrhotic Patients

BACKGROUND AND AIMS

Computed tomography (CT) provides scans of the human body from which digitized features can be extracted. The aim of this study was to examine the role of these digital biomarkers for predicting subsequent occurrence of hepatocellular carcinoma (HCC) in cirrhotic patients.

METHODS

A cohort of 269 patients with cirrhosis were recruited and prospectively followed for the occurrence of HCC in Taiwan. CT scans were retrospectively retrieved and computationally processed using analytic morphomics. A predictive score was constructed using Cox regression and the generalized iterative modeling method, maximizing the log likelihood of the time to HCC development. An independent cohort of 274 patients from University of Michigan was utilized to examine the predictive validity of this score in a Western population.

RESULTS

Of the 27 digitized features at the 12th thoracic vertebral level, six features were significantly associated with HCC occurrence. Two digitized features (fascia eccentricity and the bone mineral density) were able to stratify patients into high- and low-risk groups with distinct cumulative incidence of HCC in both the training and validation cohorts (P = 0.015 and 0.044, respectively). When the two digitized features were tested in the Michigan cohort, only bone mineral density remained an effective predictor.

CONCLUSION

Digitized features derived from the CT were effective in predicting subsequent occurrence of HCC in cirrhosis patients. The bone mineral density measured on CT was an effective predictor for patients in both Taiwan and USA.

Enhancement of sorafenib-mediated death of Hepatocellular carcinoma cells by Carnosic acid and Vitamin D2 analog combination

Hepatocellular carcinoma (HCC) is the most common form of liver cancer and it is the third leading cause of global cancer mortality. Sorafenib (Sf) is the first oral multi-kinase inhibitor approved for systemic treatment of advanced HCC, and can prolong survival, although only for three months longer than placebo treated patients. Preclinical studies showed that active forms of vitamin D can induce cell differentiation and regulate cell survival in several cell types, and epidemiological data link vitamin D insufficiency to an increased risk of neoplastic diseases, suggesting a potentially important role of vitamin D in cancer therapy. Other studies showed that the effect of vitamin D analogs on human neoplastic cells is potentiated by carnosic acid (CA), a plant polyphenol with anti-oxidant properties. Here we tested if the addition of the vitamin D2 analog Doxercalciferol (D2) together with CA can enhance the cytotoxic effect of Sf on HCC cell lines Huh7 (Sf-sensitive) and HCO2 (Sf-resistant). Indeed, this combination increased HCC cell death in cell lines, enhancing autophagy as well as apoptosis. Autophagy was confirmed by increased cytoplasmic vacuolation, perinuclear aggregation of LC3, and elevated protein levels of autophagy markers Beclin1, Atg3, and LC3. These results suggest that a regimen which combines a vitamin D2 analog/CA mixture with Sf can be a novel and promising therapeutic option for the treatment of HCC.

A Concise Review on the Frequency, Major Risk Factors and Surveillance of Hepatocellular Carcinoma (HCC) in β-Thalassemias: Past, Present and Future Perspectives and the ICET-A Experience

Due to the recent alarming increase in the incidence of hepatocellular carcinoma (HCC) in thalassemias, the present report reviews briefly the frequency, the major risk factors, and the surveillance of HCC in β-thalassemias. Over the past 33 years, 153 cases of HCC were reported in patients with thalassemia, mainly in Italy and Greece. Among HCV-infected patients, additional factors promoting the development of HCC included: advanced age, male sex, chronic hepatitis B (CHB) co-infection, and iron overload. For early diagnosis of HCC, sequential ultrasound screening is recommended especially for thalassemia patients with chronic hepatitis C (CHC), which coincides with (one or more) additional risk factors for HCC. Here we report also the preliminary data from thalassemic patients, above the age of 30 years, followed in 13 ICET-A centers. The total number of enrolled patients was 1,327 (males: 624 and 703 females). The prevalence of HCC in thalassemia major patients [characterized by transfusion-dependency (TDT)] and thalassemia intermedia [characterized by nontransfusion dependency (NTDT)] was 1.66 % and 1.96 %, respectively. The lowest age at diagnosis of HCC was 36 years for TDT and 47 years for NTDT patients. We hope that this review can be used to develop more refined and prospective analyses of HCC magnitude and risk in patients with thalassemia and to define specific international guidelines to support clinicians for early diagnosis and treatment of HCC in thalassemic patients.

25-OH-vitamin D deficiency identifies poor tumor response in hepatocellular carcinoma treated with transarterial chemoembolization

PURPOSE

Vitamin D is implicated linked to liver cancer and chronic liver diseases, but its association with tumor response in hepatocellular carcinoma (HCC) patients undergoing transarterial chemoembolization (TACE) remains unclear. This study aimed to determine whether vitamin D levels influence tumor response in HCC patients treated with TACE.

METHODS

A total of 58 HCC patients undergoing TACE were enrolled in the study. Serum 25-hydroxyvitamin D (25-OHD) levels were determined at baseline and 1 day after TACE using electrochemiluminescence immunoassay. Response to TACE was evaluated after a 4-6 week interval. Univariate and multivariate analyses with Cox regression model were performed to determine the risk factors associated with tumor response. Receiver operating characteristic (ROC) curve analysis was performed to assess the predictive performance of baseline 25-OHD levels on tumor response in HCC patients undergoing TACE.

RESULTS

43.1% of HCC patients showed 25-OHD deficiency. Baseline 25-OHD level was associated with liver cirrhosis (P = 0.025), vascular invasion (P = 0.031), Barcelona Clinic Liver Cancer stage (P = 0.002) and an alanine aminotransferase increase after TACE (P = 0.021). Serum 25-OHD level was significantly decreased 1 day after TACE (P = 0.045). Multiple tumor numbers (P = 0.034) and low baseline 25-OHD levels (P = 0.040) were independently correlated with poor tumor response after TACE. ROC curve analysis showed that baseline 25-OHD levels present better predictive performance for OR in those patients, compared with other current clinical test pointers.

CONCLUSION

Our study suggested that 25-OHD deficiency at baseline is a prognostic indicator for a poor tumor response in hepatocellular carcinoma treated with TACE.

Vitamin D potentiates anti-tumor activity of 5-fluorouracil via modulating caspase-3 and TGF-β1 expression in hepatocellular carcinoma-induced in rats

We investigated the role of vitamin D (Vit D) alone and in combination with 5-fluorouracil (5-FU) in thioacetamide (TAA)-induced hepatocellular carcinoma (HCC) in rats. Fifty male Sprague-Dawley rats were randomized into a control group and 4 groups that received TAA (200 mg/kg, i.p.) twice per week for 16 weeks. These 4 groups were further divided as follows: HCC group; 5-FU group (75 mg/kg, i.p., once weekly for 3 weeks starting from the 12th week); Vit D group (200 IU/kg daily by oral tube for 16 weeks); and 5-FU + Vit D group (received the previously mentioned dosage regimens of 5-FU and Vit D). HCC was detected by histopathological changes in liver sections and the elevation of serum α-fetoprotein (AFP). Treatment with 5-FU + Vit D significantly decreased gene expression of nuclear factor erythroid 2-related factor 2 (NrF2) and transforming growth factor β1 (TGF-β1) at both the gene and protein level and serum AFP concentrations in comparison with their corresponding monotherapy. Moreover, 5-FU + Vit D treatment enhanced apoptosis by increasing caspase-3 gene and protein expression. Conclusively, Vit D enhances antitumor activity of 5-FU in an HCC-induced model and improves liver function of treated animals. Combination therapy in a TAA-induced HCC rat model was more effective than 5-FU or Vit D through the modulation of TGF-β1, caspase-3, and NrF2 expressions.