Liver expression of steroid hormones and Apolipoprotein D receptors in hepatocellular carcinoma

Tamoxifen for adults with hepatocellular carcinoma

RATIONALE

Hepatocellular carcinoma is the most common type of liver cancer, accounting for 70% to 85% of individuals with primary liver cancer. Tamoxifen has been evaluated in randomised clinical trials in people with hepatocellular cancer. The reported results have been inconsistent.

OBJECTIVES

To evaluate the benefits and harms of tamoxifen or tamoxifen plus any other anticancer drugs compared with no intervention, placebo, any type of standard care, or alternative treatment in adults with hepatocellular carcinoma, irrespective of sex, administered dose, type of formulation, and duration of treatment.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, CENTRAL, MEDLINE, Embase, three other databases, and major trials registries, and handsearched reference lists up to 26 March 2024.

ELIGIBILITY CRITERIA

Parallel-group randomised clinical trials including adults (aged 18 years and above) diagnosed with advanced or unresectable hepatocellular carcinoma. Had we found cross-over trials, we would have included only the first trial phase. We did not consider data from quasi-randomised trials for analysis.

OUTCOMES

Our critical outcomes were all-cause mortality, serious adverse events, and health-related quality of life. Our important outcomes were disease progression, and adverse events considered non-serious.

RISK OF BIAS

We assessed risk of bias using the RoB 2 tool.

SYNTHESIS METHODS

We used standard Cochrane methods and Review Manager. We meta-analysed the outcome data at the longest follow-up. We presented the results of dichotomous outcomes as risk ratios (RR) and continuous data as mean difference (MD), with 95% confidence intervals (CI) using the random-effects model. We summarised the certainty of evidence using GRADE.

INCLUDED STUDIES

We included 10 trials that randomised 1715 participants with advanced, unresectable, or terminal stage hepatocellular carcinoma. Six were single-centre trials conducted in Hong Kong, Italy, and Spain, while three were conducted as multicentre trials in single countries (France, Italy, and Spain), and one trial was conducted in nine countries in the Asia-Pacific region (Australia, Hong Kong, Indonesia, Malaysia, Myanmar, New Zealand, Singapore, South Korea, and Thailand). The experimental intervention was tamoxifen in all trials. The control interventions were no intervention (three trials), placebo (six trials), and symptomatic treatment (one trial). Co-interventions were best supportive care (three trials) and standard care (one trial). The remaining six trials did not provide this information. The number of participants in the trials ranged from 22 to 496 (median 99), mean age was 63.7 (standard deviation 4.18) years, and mean proportion of men was 74.7% (standard deviation 42%). Follow-up was three months to five years.

SYNTHESIS OF RESULTS

Ten trials evaluated oral tamoxifen at five different dosages (ranging from 20 mg per day to 120 mg per day). All trials investigated one or more of our outcomes. We performed meta-analyses when at least two trials assessed similar types of tamoxifen versus similar control interventions. Eight trials evaluated all-cause mortality at varied follow-up points. Tamoxifen versus the control interventions (i.e. no treatment, placebo, and symptomatic treatment) results in little to no difference in mortality between one and five years (RR 0.99, 95% CI 0.92 to 1.06; 8 trials, 1364 participants; low-certainty evidence). In total, 488/682 (71.5%) participants died in the tamoxifen groups versus 487/682 (71.4%) in the control groups. The separate analysis results for one, between two and three, and five years were comparable to the analysis result for all follow-up periods taken together. The evidence is very uncertain about the effect of tamoxifen versus no treatment on serious adverse events at one-year follow-up (RR 0.44, 95% CI 0.19 to 1.06; 1 trial, 36 participants; very low-certainty evidence). A total of 5/20 (25.0%) participants in the tamoxifen group versus 9/16 (56.3%) participants in the control group experienced serious adverse events. One trial measured health-related quality of life at baseline and at nine months' follow-up, using the Spitzer Quality of Life Index. The evidence is very uncertain about the effect of tamoxifen versus no treatment on health-related quality of life (MD 0.03, 95% CI -0.45 to 0.51; 1 trial, 420 participants; very low-certainty evidence). A second trial found no appreciable difference in global health-related quality of life scores. No further data were provided. Tamoxifen versus control interventions (i.e. no treatment, placebo, or symptomatic treatment) results in little to no difference in disease progression between one and five years' follow-up (RR 1.02, 95% CI 0.91 to 1.14; 4 trials, 720 participants; low-certainty evidence). A total of 191/358 (53.3%) participants in the tamoxifen group versus 198/362 (54.7%) participants in the control group had progression of hepatocellular carcinoma. Tamoxifen versus control interventions (i.e. no treatment or placebo) may have little to no effect on adverse events considered non-serious during treatment, but the evidence is very uncertain (RR 1.17, 95% CI 0.45 to 3.06; 4 trials, 462 participants; very low-certainty evidence). A total of 10/265 (3.8%) participants in the tamoxifen group versus 6/197 (3.0%) participants in the control group had adverse events considered non-serious. We identified no trials with participants diagnosed with early stages of hepatocellular carcinoma. We identified no ongoing trials.

AUTHORS' CONCLUSIONS

Based on the low- and very low-certainty evidence, the effects of tamoxifen on all-cause mortality, disease progression, serious adverse events, health-related quality of life, and adverse events considered non-serious in adults with advanced, unresectable, or terminal stage hepatocellular carcinoma when compared with no intervention, placebo, or symptomatic treatment could not be established. Our findings are mostly based on trials at high risk of bias with insufficient power (fewer than 100 participants), and a lack of trial data on clinically important outcomes. Therefore, firm conclusions cannot be drawn. Trials comparing tamoxifen administered with any other anticancer drug versus standard care, usual care, or alternative treatment as control interventions were lacking. Evidence on the benefits and harms of tamoxifen in participants at the early stages of hepatocellular carcinoma was also lacking.

FUNDING

This Cochrane review had no dedicated funding.

REGISTRATION

Protocol available via DOI: 10.1002/14651858.CD014869.

Secondary Cancer after Androgen Deprivation Therapy in Prostate Cancer: A Nationwide Study

PURPOSE

Androgen signaling is associated with various secondary cancer, which could be promising for potential treatment using androgen deprivation therapy (ADT). This study investigated whether ADT use was associated with secondary cancers other than prostate cancer in a nationwide population-based cohort.

MATERIALS AND METHODS

A total, 278,434 men with newly diagnosed prostate cancer between January 1, 2002 and December 31, 2017 were identified. After applying the exclusion criteria, 170,416 men were enrolled. The study cohort was divided into ADT and non-ADT groups by individual matching followed by propensity score matching (PSM). Study outcomes were incidence of all male cancers. Cox proportional hazard regression models were used to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of events.

RESULTS

During a median follow-up of 4.5 years, a total of 11,059 deaths (6,329 in the ADT group and 4,730 in the non-ADT group) after PSM were found. After PSM, the overall all-cause of secondary cancer incidence risk of the ADT group was higher than that of the non-ADT group (HR: 1.312, 95% CI: 1.23-1.36; adjusted HR: 1.344, 95% CI: 1.29-1.40). The ADT group showed higher risk of overall brain and other central nervous system (CNS) cancer-specific incidence than the non-ADT group (adjusted HR: 1.648, 95% CI: 1.21-2.24). The ADT group showed lower risks of overall cancer-specific incidence for stomach, colon/rectum, liver/inflammatory bowel disease (IBD), gall bladder/extrahepatic bile duct, lung, bladder, and kidney cancers than the non-ADT group. When the duration of ADT was more than 2 years of ADT, the ADT group showed higher risk of cancer-specific incidence for brain and other CNS cancers but lower risk of cancer-specific incidence for liver/IBD and lung cancers than the non-ADT group.

CONCLUSIONS

This study demonstrates that ADT could affect cancer-specific incidence for various cancers.

Glia Maturation Factor Beta as a Novel Biomarker and Therapeutic Target for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common types of cancer. The novel sensitive biomarkers and therapeutic targets are urgently needed for the early diagnosis of HCC and improvement of clinical outcomes. Glia maturation factor-β (GMFB) is a growth and differentiation factor for both glia and neurons and has been found to be tightly involved in inflammation and neurodegeneration conditions. In our study, the expression level of GMFB was significantly up-regulated in patients with HCC and positively co-expression with tumor node metastases (TNM) stage and histopathological grade of HCC. The high expression level of GMFB was remarkably associated with poor overall survival, which mainly occurred in males rather than females. Multivariate analysis revealed GMFB to be an independent prognostic factor for overall survival in patients with HCC. Results of Gene Ontology (GO) and KEGG pathways analysis showed that down-regulation of pathways related to protein translation and mitochondria function were enriched. Protein-protein interaction analysis revealed the central role of mitochondria protein in HCC. The downregulation of genes involved in glycolysis and gluconeogenesis was observed among the co-expression genes of GMFB. Knockdown of GMFB in Hep3B significantly inhibited proliferation, migration, and invasion of Hep3B cells, and also downregulated the expression levels of some of metal matrix proteinase (MMP), increased mtDNA copy number and loss of mitochondrial transmembrane potential. GMFB influences the malignancy rate of HCC possibly through regulation of the expression of MMPs, mtDNA function and glycolysis. We proposed that GMFB was a promising HCC diagnostic and prognostic biomarker and therapeutic target in HCC.

The Lipocalin Apolipoprotein D Functional Portrait: A Systematic Review

Apolipoprotein D is a chordate gene early originated in the Lipocalin protein family. Among other features, regulation of its expression in a wide variety of disease conditions in humans, as apparently unrelated as neurodegeneration or breast cancer, have called for attention on this gene. Also, its presence in different tissues, from blood to brain, and different subcellular locations, from HDL lipoparticles to the interior of lysosomes or the surface of extracellular vesicles, poses an interesting challenge in deciphering its physiological function: Is ApoD a moonlighting protein, serving different roles in different cellular compartments, tissues, or organisms? Or does it have a unique biochemical mechanism of action that accounts for such apparently diverse roles in different physiological situations? To answer these questions, we have performed a systematic review of all primary publications where ApoD properties have been investigated in chordates. We conclude that ApoD ligand binding in the Lipocalin pocket, combined with an antioxidant activity performed at the rim of the pocket are properties sufficient to explain ApoD association with different lipid-based structures, where its physiological function is better described as lipid-management than by long-range lipid-transport. Controlling the redox state of these lipid structures in particular subcellular locations or extracellular structures, ApoD is able to modulate an enormous array of apparently diverse processes in the organism, both in health and disease. The new picture emerging from these data should help to put the physiological role of ApoD in new contexts and to inspire well-focused future research.

Clinicopathological and Prognostic Significance of Klotho and Estrogen Receptors Expression in Human Hepatocellular Carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is male-predominant cancer, but the underlying mechanism remains unclear. This study aimed to investigate the expression of the age-suppressing gene klotho and estrogen receptors (ERs) in HCC patients and analyze their association with clinicopathological variables and their effects on prognosis.

METHODS

The expression patterns of klotho, ERα, and ERβ were determined by tissue microarray and immunohistochemical technique, and their correlations with clinicopathological characteristics were investigated using univariate and multivariate analysis.

RESULTS

Klotho expression was significantly lower in HCC than in the adjacent noncancerous tissues (52.7% (49/93) vs. 90.8% (79/87), P = .000), and its protein level in HCC tissue was negatively correlated with clinical staging, histological grade, and stage of the primary tumor (T) (P < .05). Whereas the expression of nuclear ERα and ERβ was higher in HCC than their corresponding non-neoplastic tissues (55.9% (52/93) vs. 35.6% (31/87), P = .006; 59.1% (55/93) vs. 43.7% (38/87), P = .038), and the level of nuclear ERα and ERβ in HCC tissue was inversely correlated with T stage, tumor size, and clinical staging (P < .05). Correlation analysis showed the expression level of klotho, which is positively correlated with that of nuclear ERα (r = 0.243, P = .019). Patients with klotho-positive tumors had longer survival than those with klotho-negative tumors (P = .002). Cox proportional hazards model analysis demonstrated that positive expression of klotho was an important factor indicating good prognosis (P = .003).

CONCLUSION

Klotho, partially regulated by ERα-mediated estrogen pathway, acts as a tumor suppressor and might be a novel biomarker candidate for predicting progression and prognosis in HCC patients.

Inhibition of androgen/AR signaling inhibits diethylnitrosamine (DEN) induced tumour initiation and remodels liver immune cell networks

A promotional role for androgen receptor (AR) signaling in hepatocellular carcinogenesis is emerging. In pre-clinical models, including diethylnitrosamine- (DEN-) induced hepatocellular carcinoma (HCC), anti-androgen therapies delay hepatocarcinogenesis. However, pharmacologic anti-androgen therapy in advanced HCC patients fails, suggesting that AR plays a role in HCC onset. This study aims to characterize AR expression and function throughout DEN-induced liver inflammation and carcinogenesis and evaluate the efficacy of prophylactic AR antagonism to prevent hepatocarcinogenesis. We demonstrate that pharmacologic AR antagonism with enzalutamide inhibits hepatocellular carcinogenesis. With enzalutamide treatment, we observe decreased CYP2E1 expression, reducing DEN-induced hepatocyte death and DNA ethyl-adducts. AR protein expression analyses show that DEN causes an initial upregulation of AR in portal fibroblasts and leukocytes, but not hepatocytes, suggesting that hepatocyte-autonomous AR signaling is not essential for DEN-induced carcinogenesis. Ablating androgen signaling by surgical castration reduced pre-carcinogen Kupffer cell populations but did not alter DEN-mediated immune cell recruitment nor AR expression. In this study, we identified that anti-androgen interventions modulate mutagenic DNA adducts, tumour initiation, and immune cell composition. Additionally, we find that AR expression in hepatocytes is not present during nor required for early DEN-mediated carcinogenesis.

Apolipoprotein: prospective biomarkers in digestive tract cancer

Digestive tract cancer, which is characterized by high morbidity and mortality, seriously affects the quality of life of patients worldwide. The digestive tract has abundant blood supply and nutriment, providing a suitable environment for tumor cells. Under chemical, physical, and biological stimuli, the activated cancer-related genes promote tumorigenesis. The synthesis of apolipoprotein occurs in the liver, intestine, and other digestive organs. However, the functions of apolipoproteins are not limited to lipid metabolism. An increasing number of studies have revealed that apolipoproteins take part in the regulation of tumor behavior. Apolipoprotein A (apoA) has recently been acknowledged as a beneficial indicator of several cancers, including colon, hepatocellular, and pancreatic cancer. Apolipoprotein E (apoE) can affect tumor susceptibility on account of genetic polymorphism. Levels of apolipoprotein C (apoC), B (apoB), and D (apoD) also impact tumor progression and the prognosis of patients. However, because of individual, racial, and genetic differences, a consensus has not yet been reached. Based on clinical data and analysis, apolipoproteins could be a novel target and marker in tumor therapy and prevention.

Altered expression of COX-2 and TNF-α in patients with hepatocellular carcinoma

BACKGROUND AND AIM

hepatocellular carcinoma is a type of cancer related with inflammation, as 90% of cases develop in a chronic inflammation condition. Excess inflammation can affect tissue homeostasis. Cytokines and inflammatory mediators are immunological components that can influence the functioning of cells and tissues. In addition, the estrogen receptor appears to play an important role in hepatocarcinogenesis. The aim of the study was to evaluate the expression of inflammatory markers and ER in patients with hepatocellular carcinoma.

METHODS

data from 143 patients of ISCMPA were analyzed. Immunohistochemistry was performed of cyclooxygenase-2 enzyme (COX-2), nuclear factor kappa B (NF-κB), tumor necrosis factor alpha (TNF-α) and ER in paraffin-embedded hepatic tissue. The percentage of the stained area, intensity of staining and of the number of ER positive nuclei were evaluated using the ImageJ 1.50 software.

RESULTS AND CONCLUSION

there was a significant difference between the groups in terms of the percentage of marked area (p = 0.040) for COX-2 and the intensity of staining of TNF-α (p = 0.030). No significant differences were observed in any of other parameters evaluated. In conclusion, COX-2 and TNF-α are possible markers that should be further studied to determine their immunohistochemical profile and role in HCC development.

Significance and mechanism of androgen receptor overexpression and androgen receptor/mechanistic target of rapamycin cross-talk in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a male-dominant cancer, and androgen receptor (AR) has been linked to the pathogenesis of HCC. However, AR expression and its precise role in HCC remain controversial. Moreover, previous antiandrogen and anti-AR clinical trials in HCC failed to demonstrate clinical benefits. In this study, we found that AR is overexpressed in the nucleus of approximately 37% of HCC tumors, which is significantly associated with advanced disease stage and poor survival. AR overexpression in HCC cells markedly alters AR-dependent transcriptome, stimulates oncogenic growth, and determines therapeutic response to enzalutamide, a second generation of AR antagonist. However, AR inhibition evokes feedback activation of AKT-mTOR (mechanistic target of rapamycin) signaling, a central regulator for cell growth and survival. On the other hand, mTOR promotes nuclear AR protein expression by restraining ubiquitin-dependent AR degradation and enhancing AR nuclear localization, providing a mechanistic explanation for nuclear AR overexpression in HCC. Finally, cotargeting AR and mTOR shows significant synergistic anti-HCC activity and decreases tumor burden by inducing apoptosis in vivo.

CONCLUSION

Nuclear AR overexpression is associated with the progression and prognosis of HCC. However, enzalutamide alone has limited therapeutic utility attributed to feedback activation of the AKT-mTOR pathway. Moreover, mTOR drives nuclear AR overexpression. Cotargeting AR and mTOR is a promising therapeutic strategy for HCC. (Hepatology 2018;67:2271-2286).

Progesterone receptor membrane component 1 as a potential prognostic biomarker for hepatocellular carcinoma

AIM

To investigate the clinicopathological significance of progesterone receptor membrane component 1 (PGRMC1) and PGRMC2 in hepatocellular carcinoma (HCC).

METHODS

We performed immunohistochemical staining to evaluate the estrogen receptor (ER), progesterone receptor (PR), PGRMC1, and PGRMC2 in a clinical cohort consisting of 89 paired HCC and non-tumor liver samples. We also analyzed HCC data (n = 373) from The Cancer Genome Atlas (TCGA). We correlated the expression status of PGRMC1 and PGRMC2 with clinicopathological indicators and the clinical outcomes of the HCC patients. We knocked down or overexpressed PGRMC1 in HCC cell lines to evaluate its biological significance in HCC cell proliferation, differentiation, migration, and invasion.

RESULTS

We found that few HCC cases expressed ER (5.6%) and PR (4.5%). In contrast, most HCC cases expressed PGRMC1 (89.9%) and PGRMC2 (100%). PGRMC1 and PGRMC2 exhibited significantly lower expression in tumor tissue than in non-tumor tissue (P < 0.001). Lower PGRMC1 expression in HCC was significantly associated with higher serum alpha-fetoprotein expression (P = 0.004), poorer tumor differentiation (P = 0.045) and liver capsule penetration (P = 0.038). Low PGRMC1 expression was an independent predictor for worse disease-free survival (P = 0.002, HR = 2.384, CI: 1.377-4.128) in our cases, as well as in the TCGA cohort (P < 0.001, HR = 2.857, CI: 1.781-4.584). The expression of PGRMC2 did not relate to patient outcome. PGRMC1 knockdown promoted a poorly differentiated phenotype and proliferation of HCC cells in vitro, while PGRMC1 overexpression caused the opposite effects.

CONCLUSION

PGRMC1 is a non-classical hormonal receptor that negatively regulates hepatocarcinogenesis. PGRMC1 down-regulation is associated with progression of HCC and is a poor prognostic indicator.

AR-Signaling in Human Malignancies: Prostate Cancer and Beyond

In the 1940s Charles Huggins reported remarkable palliative benefits following surgical castration in men with advanced prostate cancer, and since then the androgen receptor (AR) has remained the main therapeutic target in this disease. Over the past couple of decades, our understanding of AR-signaling biology has dramatically improved, and it has become apparent that the AR can modulate a number of other well-described oncogenic signaling pathways. Not surprisingly, mounting preclinical and epidemiologic data now supports a role for AR-signaling in promoting the growth and progression of several cancers other than prostate, and early phase clinical trials have documented preliminary signs of efficacy when AR-signaling inhibitors are used in several of these malignancies. In this article, we provide an overview of the evidence supporting the use of AR-directed therapies in prostate as well as other cancers, with an emphasis on the rationale for targeting AR-signaling across tumor types.

The androgen receptor as an emerging target in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the male-dominant liver diseases with poor prognosis, although treatments for HCC have been progressing in the past decades. Androgen receptor (AR) is a member of the nuclear receptor superfamily. Previous studies reported that AR was expressed in human HCC and non-HCC tissues. AR is activated both ligand-dependently and ligand-independently. The latter is associated with a mitogen-activated protein kinase–, v-akt murine thymoma viral oncogene homolog 1–, or signal-transducer and activator of transcription–signaling pathway, which has been implicated in the development of HCC. It has been reported that more than 200 RNA expression levels are altered by androgen treatment. In the liver, androgen-responsive genes are cytochrome P450s, transforming growth factor β, vascular endothelial growth factor, and glucose-regulated protein 78 kDa, which are also associated with human hepatocarcinogenesis. Recent studies also revealed that AR plays a role in cell migration and metastasis. It is possible that cross-talk among AR-signaling, endoplasmic reticulum stress, and innate immune response is important for human hepatocarcinogenesis and HCC development. This review shows that AR could play a potential role in human HCC and represent one of the important target molecules for the treatment of HCC.

Androgen receptor in hepatocarcinogenesis: Recent developments and perspectives

Previous studies have indicated that males are at a higher risk of developing hepatocellular carcinoma (HCC) compared with females. Identifying the factors that cause this gender-specific difference in the incidence of HCC has long been considered important for revealing the molecular mechanisms involved in hepatocarcinogenesis. Given the unprecedented tools that are now available for molecular research, genetic studies have established that the androgen receptor (AR) may be partly responsible for gender disparity in HCC. AR has a dual role, promoting HCC initiation and development, as well as suppressing HCC metastasis. The present review provides an overview of the involvement of AR signaling in HCC. The review highlighted important studies, examples of the direct AR transcriptional target genes involved in HCC and novel theories concerning the conventional concept, suggesting that targeting the AR, rather than the androgen, may provide an improved therapeutic approach for the treatment of HCC.

Tissue concentrations of estrogens and aromatase immunolocalization in interstitial pneumonia of human lung

Interstitial pneumonia (IP) is characterized by various degrees of pulmonary fibrosis and inflammation. Estrogens have been demonstrated to play important roles in physiological and pathological conditions of human lung, but significance of estrogens has remained unknown in human IP. Therefore, we measured estrogen concentrations and immunolocalized aromatase and estrogen receptor β (ERβ) in IP tissues. Estradiol concentration was significantly (2.8-fold) higher in IP than normal lung tissues, and aromatase activity evaluated by estradiol/testosterone ratio was also significantly (7.2-fold) elevated in IP tissues. Aromatase immunoreactivity in alveolar epithelial cells was significantly frequent in IP than normal lung or inflammatory lung disease other than IP, and it was positively associated with ERβ immunoreactivity in these cells of IP. These results suggest that estradiol concentration is locally increased in human IP tissue by aromatase, and increased estrogens may play an important role in the development of IP through ERβ in the alveolar epithelial cells.

Androgen receptor roles in hepatocellular carcinoma, fatty liver, cirrhosis and hepatitis

Androgen/androgen receptor (AR) signaling plays important roles in normal liver function and in progression of liver diseases. In studies of noncancerous liver diseases, AR knockout mouse models of liver disease have revealed that androgen/AR signaling suppresses the development of steatosis, virus-related hepatitis, and cirrhosis. In addition, studies have shown that targeting AR in bone marrow-derived mesenchymal stem cells (BM-MSCs) improves their self-renewal and migration potentials, thereby increasing the efficacy of BM-MSC transplantation as a way to control the progression of cirrhosis. Androgen/AR signaling is known to be involved in the initiation of carcinogen- or hepatitis B virus-related hepatocellular carcinoma (HCC). However, studies have demonstrated that AR, rather than androgen, plays the dominant role in cancer initiation. Therefore, targeting AR might be an appropriate therapy for patients with early-stage HCC. In contrast, androgen/AR signaling has been shown to suppress metastasis of HCC in patients with late-stage disease. In addition, there is evidence that therapy comprising Sorafenib and agents that enhance the functional expression of AR may suppress the progression of late-stage HCC.

Expression and potential role of apolipoprotein D on the death-survival balance of human colorectal cancer cells under oxidative stress conditions

PURPOSE

Inverse correlations of apolipoprotein D (ApoD) expression with tumor growth have been shown, therefore proposing ApoD as a good prognostic marker for diverse cancer types, including colorectal cancer (CRC). Besides, ApoD expression is boosted upon oxidative stress (OS) in many pathological situations. This study aims at understanding the role of ApoD in the progression of human CRC.

METHODS

Samples of CRC and distant normal tissue (n = 51) were assayed for levels of lipid peroxidation, expression profile of OS-dependent genes, and protein expression. Three single-nucleotide polymorphisms in the ApoD gene were analyzed (n = 139), with no significant associations found. Finally, we assayed the effect of ApoD in proliferation and apoptosis in the CRC HT-29 cell line.

RESULTS

In CRC, lipid peroxides increase while ApoD messenger RNA and protein decrease through tumor progression, with a prominent decrease in stage I. In normal mucosa, ApoD protein is present in lamina propia and enteroendocrine cells. In CRC, ApoD expression is heterogeneous, with low expression in stromal cells commonly associated with high expression in the dysplastic epithelium. ApoD promoter is basally methylated in HT-29 cells but retains the ability to respond to OS. Exogenous addition of ApoD to HT-29 cells does not modify proliferation or apoptosis levels in control conditions, but it promotes apoptosis upon paraquat-induced OS.

CONCLUSION

Our results show ApoD as a gene responding to OS in the tumor microenvironment. Besides using ApoD as marker of initial stages of tumor progression, it can become a therapeutic tool promoting death of proliferating tumor cells suffering OS.

Estrogen signalling through amphiregulin may be implicated in human hepatocellular carcinoma

BACKGROUND

We investigated aromatase (Aro)-driven estrogen formation in non-tumoral and malignant liver tissues and cells, also in relation to expression of the estrogen receptors α and β (ERα and ERβ) and amphiregulin (AREG), aiming to gain insights into the potential role of estrogens in human hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Chromatographic and reverse transcriptase polymerase chain reaction (RT-PCR) analyses were used to assess activity and expression of the Aro enzyme and AREG as well as the expression of wild-type and variant ERs, both in vivo and in vitro.

RESULTS

Following 24 h and 72 h incubation of liver tissues or cells with testosterone, human HCC tissues and HepG2 hepatoma cells showed elevated Aro activity (estrogen formation, respectively, of 20% and 52%-99%). By contrast, no Aro activity could be detected in non-tumoral tissues and HA22T liver cancer cells. Cirrhotic samples and Huh7 cells exhibited intermediate enzyme activity, with estrogen formation of 4% and 34%, respectively. Markedly lower or undetectable Aro mRNA levels were observed in HA22T cells and non-tumoral liver tissues compared with HepG2 cells and HCC samples. Cirrhotic specimens displayed variable transcript levels. Interestingly, no or low expression of wild-type ERα and ERβ could be observed in liver cancer cells and malignant tissues. However, ubiquitous expression of the hERα46 variant and occasional expression of the hERβ2/Cx variant were observed in cancer tissues and cells.

CONCLUSIONS

It is noteworthy that the pattern of wild-type ERα was inversely related to Aro, whilst AREG expression was consistently associated with that of Aro. This combined evidence suggests that locally elevated Aro activity may increase malignant cell proliferation also through AREG signalling.

Unfolded protein response activation contributes to chemoresistance in hepatocellular carcinoma

OBJECTIVE

Hepatocellular carcinoma (HCC) has an annual worldwide incidence of 626 000 cases and causes 550 000 deaths per year. Although the mainstay of treatment is surgical resection, for inoperable or metastatic disease, chemotherapy may be offered. The primary agent used is doxorubicin, but response rates are poor (<20%). The unfolded protein response (UPR) is a cytoprotective cellular stress response that enables cells to survive periods of hypoxia and nutrient deprivation. The UPR may confer resistance to anticancer agents and contribute to treatment failure. This study has investigated whether the UPR is activated in HCC and whether this may contribute to doxorubicin resistance.

METHODS

Eighty-six human HCCs were immunohistochemically stained for glucose regulated protein 78, the key marker of UPR activation. An in-vitro model of UPR activation in HepG2 HCC cells was developed by glucose deprived culture. UPR activation was confirmed with western blotting and PCR to show overexpression of glucose regulated protein 78. The relative efficacy of doxorubicin chemotherapy on UPR-activated HepG2 cells was compared with normal HepG2 cells by use of an thiazolyl blue tetrazolium bromide colorimetric assay.

RESULTS

Expression of glucose regulated protein 78 was shown in 100% of the HCC samples with 66% showing strong staining. In-vitro UPR activation was achieved with glucose deprivation. UPR activation induced significant resistance to doxorubicin: 34% survival under standard culture conditions versus 58% and 63% for UPR-activated cells in 0.5 and 1 mmol glucose respectively (P=0.00928).

CONCLUSION

The UPR is activated in HCCs and confers resistance to chemotherapy in vitro. UPR activation may contribute to HCC chemoresistance.

Cellular and molecular mechanisms involved in hepatocellular carcinoma gender disparity

Hepatocellular carcinoma (HCC) represents the most common primary liver cancer and one of the most fatal human cancers. Besides alcoholic liver disease as well as genetic and environmental factors, hepatitis B and C viral infections also represent the most important risk factors for onset and development of the disease. In fact, HCC worldwide prevalence varies widely and mirrors the geographical distribution of chronic viral hepatitis. Interestingly, a gender difference was described for this disease: in almost all populations, a male/female ratio averaging between 2:1 and 4:1 was reported. Here, we analyze the implication of cytokines and sex hormones in this issue. Exploiting the emerging knowledge on the possible differential role of hepatitis viruses B and C, we discuss the role of reactive oxygen species and apoptosis dysregulation in the characterization of the molecular mechanisms of gender disparity in the development of HCC.

A role of apolipoprotein D in triglyceride metabolism

Apolipoproteins (apo) are constituents of lipoproteins crucial for lipid homeostasis. Aberrant expression of apolipoproteins is associated with metabolic abnormalities. Here we characterized apolipoprotein D (apoD) in triglyceride metabolism. Unlike canonical apolipoproteins that are mainly produced in the liver, apoD is an atypical apolipoprotein with broad tissue distribution. We show that circulating apoD is present mainly in HDL and, to a lesser extent, in LDL and VLDL and that its plasma levels were reduced in db/db mice with visceral obesity and altered lipid metabolism. Elevated apoD production, derived from adenovirus-mediated gene transfer, resulted in significant reduction in plasma triglyceride levels in mice. This effect was attributable to en-hanced LPL activity and improved catabolism of triglyceride-rich particles. In contrast, VLDL triglyceride production remained unchanged in response to elevated apoD production. These findings were recapitulated in high-fat-induced obese mice. Obese mice with elevated apoD production exhibited significantly improved triglyceride profiles, correlating with increased plasma LPL activity and enhanced postprandial fat tolerance. ApoD was shown to promote LPL-mediated hydrolysis of VLDL in vitro, correlating with its TG-lowering action in vivo. Apolipoprotein D plays a significant role in lipid metabolism. These data provide important clues to clinical observations that genetic variants of apoD are associated with abnormal lipid metabolism and increased risk of metabolic syndrome.

Expression of metalloproteases and their inhibitors in primary tumors and in local recurrences after mastectomy for breast cancer

AIMS

To investigate the expression of matrix metalloproteases (MMPs) and their inhibitors (TIMPs) in patients who develop local recurrence (LR) after mastectomy.

METHODS

We analyzed the expressions of MMP-1, -2, -7, -9, -11, -13, -14, TIMP-1, -2, and -3, using immunohistochemical techniques, in primary tumors from patients without tumoral recurrence (n = 50), patients who developed distant metastasis (n = 50), and from patients who develop LRs (n = 25). LRs of the latter group were also analyzed for MMPs expression. All the patients underwent mastectomy.

RESULTS

Score values for all MMPs and TIMPs were significantly higher in primary tumors of patients with distant metastasis. Primary tumors from patients with LR have lower expressions of MMPs and TIMPs compared with those from patients who developed distant metastasis, and with patients without recurrence for some MMPs. Remarkably, however, primary tumors from patients with LR showed significantly higher percentage of TIMP-1 and 2 expression in stromal cells compared to primary tumors from patients with distant metastasis or primary tumors from patients without tumoral progression. Furthermore, LRs had significantly higher MMP-9 expression than their corresponding primary tumors.

CONCLUSIONS

Our data indicate differences in MMPs/TIMPs expression between primary tumors of patients with LRs and of those with distant metastasis, both after mastectomy for breast cancer.

Role of sex steroid receptors in pathobiology of hepatocellular carcinoma

The striking gender disparity observed in the incidence of hepatocellular carcinoma (HCC) suggests an important role of sex hormones in HCC pathogenesis. Though the studies began as early as in 1980s, the precise role of sex hormones and the significance of their receptors in HCC still remain poorly understood and perhaps contribute to current controversies about the potential use of hormonal therapy in HCC. A comprehensive review of the existing literature revealed several shortcomings associated with the studies on estrogen receptor (ER) and androgen receptor (AR) in normal liver and HCC. These shortcomings include the use of less sensitive receptor ligand binding assays and immunohistochemistry studies for ERα alone until 1996 when ERβ isoform was identified. The animal models of HCC utilized for studies were primarily based on chemical-induced hepatocarcinogenesis with less similarity to virus-induced HCC pathogenesis. However, recent in vitro studies in hepatoma cells provide newer insights for hormonal regulation of key cellular processes including interaction of ER and AR with viral proteins. In light of the above facts, there is an urgent need for a detailed investigation of sex hormones and their receptors in normal liver and HCC. In this review, we systematically present the information currently available on androgens, estrogens and their receptors in normal liver and HCC obtained from in vitro, in vivo experimental models and clinical studies. This information will direct future basic and clinical research to bridge the gap in knowledge to explore the therapeutic potential of hormonal therapy in HCC.

Is human hepatocellular carcinoma a hormone-responsive tumor?

Before the positive results recently obtained with multitarget tyrosine kinase inhibitor sorafenib, there was no standard systemic treatment for patients with advanced hepatocellular carcinoma (HCC). Sex hormones receptors are expressed in a significant proportion of HCC samples. Following preclinical and epidemiological studies supporting a relationship between sex hormones and HCC tumorigenesis, several randomized controlled trials (RCTs) tested the efficacy of the anti-estrogen tamoxifen as systemic treatment. Largest among these trials showed no survival advantage from the administration of tamoxifen, and the recent Cochrane systematic review produced a completely negative result. This questions the relevance of estrogen receptor-mediated pathways in HCC. However, a possible explanation for these disappointing results is the lack of proper patients selection according to sex hormones receptors expression, but unfortunately the interaction between this expression and efficacy of tamoxifen has not been studied adequately. It has been also proposed that negative results might be explained if tamoxifen acts in HCC via an estrogen receptor-independent pathway, that requires higher doses than those usually administered, but an Asian RCT conducted to assess dose-response effect was completely negative. Interesting, preliminary results have been obtained when hormonal treatment (tamoxifen or megestrol) has been selected according to the presence of wild-type or variant estrogen receptors respectively, but no large RCTs are available to support this strategy. Negative results have been obtained also with anti-androgen therapy. In conclusion, there is no robust evidence to consider HCC a hormone-responsive tumor. Hormonal treatments should not be part of the current management of HCC.