Sex steroid receptor proteins in foetal, adult and malignant human liver tissue

Progestins as a Contributing Factor to Hepatocellular Adenoma: A Case Series and Literature Review

STUDY OBJECTIVE

To explore the role of progestins as potential contributing factors for the development of hepatocellular adenoma (HA) METHODS: We describe 3 cases of adolescents and young adults who developed HA while on norethindrone (NET), as well as their management. In addition, we provide a comprehensive literature review on the association between progestins and HA.

RESULTS

Since 1983, 16 cases of HA in patients on progestins have been reported. Ten patients were on NET and 5 on a prodrug of NET (4 on norethindrone acetate [NETA] and 1 on lynestrenol). One individual had a norgestrel implant. Eight subsequently ceased all hormones: 4 experienced a size reduction, and 3 had complete resolution of their HA. Among our patients, 1 ceased NET and instead had a levonorgestrel intrauterine device inserted, and another swapped from NET to oral medroxyprogesterone acetate. Both experienced complete resolution of their HA. The third ceased NET and underwent a hysterectomy, with size reduction of her HA.

CONCLUSION

These cases and the literature review suggest an association between progestin exposure, in particular NET and its prodrugs, and the development of HA. The pathophysiology is unknown but may include peripheral conversion of NET and NETA to ethinyl estradiol or a specific action of 19-nortestosterone derivatives on hepatocytes, especially those with higher systemic doses compared with the levonorgestrel intrauterine device. There are no case reports relating to other forms of progestins, such as 17-hydroxyprogesterone, which may be important when considering alternative therapeutic options in females requiring effective menstrual management who have comorbidities.

The Loss of Masculine With Declined Serum DHT Is Associated With High Risk of Hepatocellular Carcinoma in Chinese Men

Background: Hepatocellular carcinoma (HCC) is a male-predominant cancer. However, the relationship between 5α-dihydrotestosterone (DHT), the active form of testosterone, and HCC risk has not been established yet. Methods: We performed a serum epidemiological study in the Chinese population. From 2010 to 2012, 106 male HCC patients and 318 age-matched controls were detected for their serum DHT and estradiol (E2). The odds ratios (ORs) and 95% confidence interval (CI) were estimated by logistic regression analysis with adjustment for potential risk factors. Bivariate Pearson correlations between hormone concentrations and liver function index were investigated. Results: Serum DHT levels were lower (to 1/3 of control), and E2 levels were higher (to 1.5-fold of control) in HCC patients. Compared with the low DHT level, men with a medium level had an adjusted multiple OR of 0.15 (95% CI 0.05-0.43, p trend < 0.01), and men with a high level had an OR of 0.05 (95% CI 0.01-0.21, p trend < 0.01). Notably, DHT concentration, but not E2, is correlated with liver injury. Conclusion: The data suggest that serum DHT is closely associated with HCC risk, providing a reference in order to accurately predict liver cancer and study the pathogenesis of this disease.

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.

Mixture effects of levonorgestrel and ethinylestradiol: estrogenic biomarkers and hormone receptor mRNA expression during sexual programming

Synthetic progesterone (progestins) and estrogens are widely used pharmaceuticals. Given that their simultaneous unintentional exposure occurs in wildlife and also in human infants, data on mixture effects of combined exposures to these hormones during development is needed. Using the Xenopus (Silurana) tropicalis test system we investigated mixture effects of levonorgestrel (LNG) and ethinylestradiol (EE2) on hormone sensitive endpoints. After larval exposure to LNG (0.1nM), or EE2 (0.1nM) singly, or in combination with LNG (0.01, 0.1, 1.0nM), the gonadal sex ratio was determined histologically and hepatic mRNA levels of genes encoding vitellogenin (vtg beta1) and the estrogen (esr1, esr2), progesterone (ipgr) and androgen (ar) receptors were quantified using quantitative PCR. All EE2-exposed groups showed female-biased sex ratios and increased vtg beta1 mRNA levels compared with the controls. Compared with the EE2-alone group (positive control) there were no significant alterations in vtg beta1 levels or in sex ratios in the co-exposure groups. Exposure to LNG-alone caused an increase in ar mRNA levels in females, but not in males, compared to the controls and the co-exposed groups, indicating that co-exposure to EE2 counteracted the LNG-induced ar levels. No treatment related impacts on the mRNA expression of esr1, esr2, and ipgr in female tadpoles were found, suggesting that these endpoints are insensitive to long-term exposure to estrogen or progestin. Due to the EE2-induced female-biased sex ratios, the mRNA expression data for the low number of males in the EE2-exposed groups were not statistically analyzed. In conclusion, our results suggest that induced vtg expression is a robust biomarker for estrogenic activity in exposure scenarios involving both estrogens and progestins. Developmental exposure to LNG caused an induction of hepatic ar mRNA expression that was antagonized by combined exposure to EE2 and LNG. To our knowledge this is the first study to report effects of combined exposures to EE2 and LNG during the period of sexual programming.

In vitro screening of environmental chemicals for targeted testing prioritization: the ToxCast project

BACKGROUND

Chemical toxicity testing is being transformed by advances in biology and computer modeling, concerns over animal use, and the thousands of environmental chemicals lacking toxicity data. The U.S. Environmental Protection Agency's ToxCast program aims to address these concerns by screening and prioritizing chemicals for potential human toxicity using in vitro assays and in silico approaches.

OBJECTIVES

This project aims to evaluate the use of in vitro assays for understanding the types of molecular and pathway perturbations caused by environmental chemicals and to build initial prioritization models of in vivo toxicity.

METHODS

We tested 309 mostly pesticide active chemicals in 467 assays across nine technologies, including high-throughput cell-free assays and cell-based assays, in multiple human primary cells and cell lines plus rat primary hepatocytes. Both individual and composite scores for effects on genes and pathways were analyzed.

RESULTS

Chemicals displayed a broad spectrum of activity at the molecular and pathway levels. We saw many expected interactions, including endocrine and xenobiotic metabolism enzyme activity. Chemicals ranged in promiscuity across pathways, from no activity to affecting dozens of pathways. We found a statistically significant inverse association between the number of pathways perturbed by a chemical at low in vitro concentrations and the lowest in vivo dose at which a chemical causes toxicity. We also found associations between a small set of in vitro assays and rodent liver lesion formation.

CONCLUSIONS

This approach promises to provide meaningful data on the thousands of untested environmental chemicals and to guide targeted testing of environmental contaminants.

Androgen metabolism and biotransformation in nontumoral and malignant human liver tissues and cells

There is indirect multiple evidence that hints at a potential role of sex steroids in development and progression of human hepatocellular carcinoma (HCC). In the present study, we have investigated androgen metabolism in a panel of human liver cancer cell lines (HA22T, Huh7, HepG2) and in normal, cirrhotic and malignant human liver tissues aiming to dissect the potential impact of individual enzyme activities and their products in normal and diseased human liver, both in vivo and in vitro. Using our intact cell analysis we were able to assess rates and pathways of androgen metabolism in living conditions. Overall, incubation of cultured cells or tissue minces with either testosterone (T) or androstenedione (Ad) used as precursor resulted in a large extent of 17betaoxidation of T to Ad (cells: 28-77%; tissues: 35-50%). In malignant liver cell lines, both HA22T and Huh7 cells showed consistent amounts of the 5alpha-reductase enzyme products (18% and 15%, respectively), while 5beta-reductase activity was more pronounced in Huh7 cells (18%) than in HA22T cells (1.8%). Interestingly, a significant extent of estrogen formation could be observed in Huh7 cells (5.4-11.5%), while no aromatase activity could be detected in HA22T cells. In HepG2 cells, along with a relatively high proportion of Ad, estrogens represented the most prominent (50-55%) end product of androgen metabolism, regardless of the precursor used. In liver tissues, equivalent results could be obtained, with a consistent proportion of 17betaoxidation of T to Ad (35-50%) being observed in the majority of samples. However, while normal liver tissue samples exhibited a minor proportion of bioactive androgens (3.4%) with no aromatase products, HCC tissues showed a significant extent of aromatase activity (nearly 20%) with estrogen representing the most prominent metabolic product after 24h incubation with either T or Ad. HCV and alcoholic cirrhotic tissues displayed different patterns of androgen metabolism. The former produced limited amounts of bioactive androgens (5.3%) and considerable levels of the intermediate aromatase product 19OH-Ad (up to 28%), the latter exhibited a prevalence of androgen degradation through the 5beta-reductase pathway (9.8%) and a significant extent of aromatase activity (16% as a whole). In conclusion, three major metabolic states could be depicted, depending on prevalent pathways of androgen metabolism and steroid receptor status: estrogenic, androgenic, and mixed. This model supports the idea that local estrogen biosynthesis may be implicated in human HCC and provides a basis for the exploitation of aromatase inhibitors and/or ER antagonists or selective estrogen receptor modulators (SERMs) as a new therapeutic strategy in HCC patients.

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.

Hepatitis C virus core protein augments androgen receptor-mediated signaling

Hepatitis C virus (HCV) infection is frequently associated with the development of hepatocellular carcinoma (HCC), which is one of the male-dominant diseases. Androgen signaling in liver may be related to carcinogenesis. In this study, we investigated whether HCV proteins cross talk with the androgen receptor (AR) signaling pathway for promotion of carcinogenesis. We have demonstrated that HCV core protein alone or in context with other HCV proteins enhances AR-mediated transcriptional activity and further augments in the presence of androgen. Subsequent study suggested that HCV core protein activates STAT3, which in turn enhances AR-mediated transcription. This activity was blocked by a pharmacological inhibitor of the Jak/Stat signaling pathway, AG490. Vascular endothelial growth factor (VEGF) is a target gene of AR in liver and plays an important role in angiogenesis. Therefore, we examined whether HCV infection modulates VEGF expression in hepatocytes. Our results demonstrated that HCV enhances VEGF expression and facilitates tube formation in human coronary microvascular endothelial cells in the presence of AR. Together, our results suggest that HCV core protein acts as a positive regulator in AR signaling, providing further insight into oncogenic potential in the development of HCC in HCV-infected individuals.

Methylation of neutral endopeptidase 24.11 promoter in rat hepatocellular carcinoma

Neutral endopeptidase 24.11 (NEP), a cell-surface enzyme expressed by epithelial cells that cleaves and inactivates biologically active small peptides, is downregulated in various cancers. NEP is encoded by a gene that contains a CpG island in the promoter region, whose hypermethylation appears related to decreased expression. Altered expression of NEP has also been reported in human hepatocellular carcinoma (HCC), suggesting its possible role in hepatocarcinogenesis. To elucidate the status of NEP in HCC, methylation in the promoter region of the gene that encodes NEP in male Fischer 344 rats with HCC, induced by a choline-deficient, l-amino acid-defined diet, was investigated by methylation-specific polymerase chain reaction, combined bisulfite restriction analysis, and bisulfite genomic sequencing. These analyses together showed the promoter to be frequently methylated in HCC in contrast to its unmethylated status in normal liver, the degree of methylation being inversely related to the level of mRNA expression evaluated by reverse transcription-polymerase chain reaction (P = 0.031). In two rat liver cell lines, RLC-16 and RLC-27, the promoter was heavily methylated and NEP mRNA expression was negative. However, administration of 5-aza-2'-deoxycytidine caused NEP expression, suggesting that methylation of CpG is a factor regulating transcriptional expression. Together with the data from microarray analyses performed previously using the same animal model, the current results suggest that reduced expression of NEP or other ectopeptidases could impact on molecules involved in signal-transducing systems, including G-protein coupled receptors, via modified turnover of extracellularly active small peptides.

Sex and androgenic steroid receptor expression in hepatic adenomas

Sex hormones and anabolic-androgenic steroids are implicated in the development and progression of hepatic adenomas (HA). We studied the expression of their receptors in HA and adjacent liver. Archival tissue sections of 27 HA (16 resections, four needle biopsies, seven aspirations) from 18 patients, and the adjacent liver, were immunostained with monoclonal antibody to estrogen receptor (ER, 1/80) (Dako, Carpinteria, CA), progesterone receptor (PR, 1/50) (BioGenex, San Ramon, CA), and androgen receptor (AR, 1/80) (BioGenex). An avidin-biotin complex technique was used with microwave antigen retrieval. Nuclear expression was assessed as 1+ to 3+ intensity, with semiquantitation of the percentage of nuclei immunopositive. Five percent or more nuclei immunopositive was regarded as positive. The 18 patients included 16 females of 34 years mean age (range, 16 to 49) with an available history of oral contraceptives in five; the two men were 24 and 30 years, with no history of androgenic steroids. ER, PR, and AR were present in seven (26%) (1+/-2+ intensity, 5% to 10% of nuclei) of HA, seven (26%) (1+/-2+ intensity, 5% to 30% of nuclei) and nine (33%) (1+/-3+ intensity, 5% to 80% of nuclei), respectively. In the adjacent liver in 11 cases, there were one (9%) ER, (2+ intensity, 5% of nuclei), four (36%) PR (1+/-2+ intensity, 5% to 20% of nuclei), and two (18%) AR (2+/-3+ intensity, 10% of nuclei). Receptors are present and may mediate the action of sex hormones or androgenic steroids on HA and adjacent liver, but in less than one third of patients. This may have therapeutic implications.

Diazepam binding inhibitor and total cholesterol plasma levels in cirrhosis and hepatocellular carcinoma

Cholesterol is used by cells for biosynthetic processes and for steroid synthesis. Although the role of cholesterol in tumorigenesis is not clear it is known that steroids are important factors in human carcinogenesis. A polypeptide, diazepam binding inhibitor (DBI), which is an endogenous ligand for peripheral benzodiazepine receptors enhances steroidigenesis by promoting cholesterol delivery to the inner mitochondrial membrane which represents the rate-limiting step of steroid biosynthesis. We have assayed the total cholesterol (TC) and the DBI plasma concentrations in patients with liver cirrhosis complicated by hepatocellular carcinoma (HCC) in comparison with those of uncomplicated liver cirrhosis. TC and DBI levels have been studied in 73 cirrhotic patients and in 23 patients with HCC. Both TC and DBI levels were higher in HCC patients when compared with age, sex and Child-Pugh class matched cirrhotic controls. The values (mean+/-S.D.) in patients in Child-Pugh class B and C with and without HCC were respectively 128+/-30 mg/dl vs. 106+/-27 mg/dl (P < 0.01) and 2.05+/-0.78 pmol/ml vs. 0.78+/-0.84 pmol/ml (P < 0.0001). The data may be the result of the metabolic influence of tumors that enhances steroid biosynthesis during tumor proliferation.

Suppressive effect of oestradiol on chemical hepatocarcinogenesis in rats

AIMS

To examine the effects of oestradiol and testosterone on the early carcinogenic changes expressed in rat liver from the diethylnitrosamine (DEN), 2-acetylaminofluorene (AAF), partial hepatectomy (PH) model of hepatocarcinogenesis.

METHODS

Preneoplastic liver lesions were evaluated using immunohistochemical analysis of glutathione-S-transferase placental form (GST-P) expression; oestrogen and androgen receptor levels were measured by radioimmunoassay.

RESULTS

Oestradiol administration to non-castrated DEN-AAF-PH treated males resulted in a decrease in the area of GST-P positive foci, while testosterone increased the serum oestradiol level and reduced the area. In males, castration alone and castration with oestradiol replacement significantly reduced the GST-P positive area, and increased the hepatic oestrogen receptor level. In DEN-AAF-PH treated females, castration with testosterone replacement was associated with a significant increase in the GST-P positive area and the hepatic androgen receptor level.

CONCLUSION

These findings suggest that exogenous and endogenous oestradiol can suppress chemical hepatocarcinogenesis. It appears that oestrogen receptors may be involved in the inhibition of malignant transformation of preneoplastic liver cells, while androgens and androgen receptors are involved in hepatocarcinogenesis.

Phase II study of megestrol acetate in the treatment of hepatocellular carcinoma

This is a report of a phase II study of megestrol acetate (160 mg/day, orally) in the treatment of hepatocellular carcinoma (HCC). Forty-six patients with advanced HCC were studied and tumour response, changes in appetite, bodyweight, a feeling of well-being, survival and toxicity were evaluated. Thirty-two patients were able to be evaluated for response; there were no complete responders or partial responders. Twelve patients (38%) had stable disease and seven of these patients had a minor response with a median size reduction in the tumour of 18%. Twenty patients (62%) had progressive disease. Five of 24 (21%) patients had a median reduction in alpha-fetoprotein levels of 59 ng/mL. The overall median survival was 4 months (range 1 week to 27 months). Twenty of 32 (62%) patients had an increased appetite and feeling of well-being. Fourteen of 22 (64%) patients had a median lean bodyweight gain of 5 kg (range 1-14 kg). Toxicities were minimal. Tests for glucocorticoid receptors were performed in 10 patients. Four of five patients who were positive for glucocorticoid receptors in the tumour had a stable disease and all five patients who were negative for glucocorticoid receptors had progressive disease. Megestrol acetate had no significant effect on the tumour in HCC patients. However, megestrol acetate is useful in the palliative management of HCC patients, with improvements in appetite, bodyweight and a feeling of well-being with minimal side effects. Some patients had stable disease, a minor reduction of tumour size and a prolonged survival after megestrol acetate treatment and this response may be related to the presence of glucocorticoid receptors in the HCC tumour.

Surgical Resection of Hepatocellular Carcinoma

BACKGROUND: Surgical management of hepatocellular carcinoma is challenging. Advances in patient selection and operative techniques are taking place in various parts of the world. METHODS: The literature on diagnosis, evaluation, and surgical treatment of hepatocellular carcinoma is reviewed and combined with the extensive clinical experience of the authors. RESULTS: While alpha-fetoprotein levels often are elevated in patients with large hepatocellular tumors, a combination of hepatic arteriography and Lipiodol computed tomography is the most sensitive imaging approach. An indocyanine green retention of more than 14% at 15 minutes predicts a poor outcome from surgery. Intraoperative ultrasound and ultrasonic dissector assist surgery. One-, three-, and five-year survival rates of 68%, 44%, and 35%, respectively, have been reported. CONCLUSIONS: Methods to diagnose and assess the suitability of patients with hepatocellular carcinoma for surgical resection are now available, and operative and postoperative care has improved. Surgery remains the "gold standard" to which other treatments can be compared.

Effect of androgens and their manipulation on cell growth and androgen receptor (AR) levels in AR-positive and -negative human hepatocellular carcinomas

BACKGROUND/AIMS

Little is known about genuine roles of androgens and their receptor in hepatocellular carcinoma.

METHODS

In the present study, two sublines derived from a human hepatocellular carcinoma cell line KYN-1 were used: KYN-1/SM10 with androgen receptor and KYN-1/SM2 without androgen receptor.

RESULTS

The binding assay with 3H-R1881 identified the presence of both cytosolic and nucleosolic androgen receptors in KYN-1/SM10 but not in KYN-1/SM2. In serum-free medium, dihydrotestosterone was able to enhance the cell proliferation and 3H-thymidine incorporation in androgen receptor positive KYN-1/SM10 cells. Such effects of dihydrotestosterone were partially inhibited by an antiandrogen cyproterone acetate in a concentration-dependent manner. On the other hand, the growth of androgen receptor negative KYN-1/SM2 cells was not influenced by dihydrotestosterone and cyproterone acetate at all. When dihydrotestosterone was removed from the medium of KYN-1/SM10 cultures, the nucleosolic androgen receptor decreased to undetectable levels within 8 h and the cytosolic androgen receptor within 48 h. Addition of dihydrotestosterone (10 nM) to the cells that had been deprived of dihydrotestosterone for 24 h partially restored both cytosolic and nucleosolic androgen receptor within 12 h.

CONCLUSION

The current results seem to indicate that the growth of androgen receptor positive human hepatocellular carcinoma may be enhanced with androgen through androgen receptors and that antiandrogen therapy with cyproterone acetate may be effective in the treatment of androgen receptor-positive hepatocellular carcinoma.

Better survival in female patients with hepatocellular carcinoma. Possible causes from a pathologic approach

BACKGROUND

Hepatocellular carcinoma is notably more prevalent in men than in women.

METHODS

To examine the sex-related characteristics of patients with primary hepatocellular carcinoma, 35 women were compared with 243 men, both groups having undergone surgical resection of the tumor.

RESULTS

Women had a lower incidence of tumor recurrence, with median disease free survival of 19.5 months compared with 4.5 months for men (P < 0.001). Women also had more favorable actuarial survival than men [36.5 months for women compared with 12.4 months for men (P = 0.002)]. Women had a significantly higher incidence (80%) of tumor encapsulation than men (45%) (P < 0.001). Furthermore, the tumors in women were frequently less invasive in terms of lower incidence of tumor microsatellites, liver invasion, and positive histologic margin. Tumor microsatellite formation was present with 16% of tumors in women, compared with 60% for men (P < 0.0001). Liver invasion was found in 37% of tumors in women and 61% in men (P = 0.03). Only 6% of tumors in women had a positive histologic margin, compared to 24% in men (P = 0.04). There was no statistical significance in the incidence of cirrhosis in the nontumorous liver, hepatitis B surface antigen positivity, mean age, or tumor size, between women and men.

CONCLUSIONS

Women who had hepatocellular carcinoma and hepatic resection had better survival rates and a lower rate of tumor recurrence than male patients. The better prognosis in women with hepatocellular carcinoma appeared to be related to the pathobiologic characteristics of the tumor (i.e., frequent encapsulation and lower tumor invasiveness).

Identification and Characterization of Glucocorticoid Receptors in Liver of Nude Mice

Glucocorticoids regulate the expression of many liver-specific genes via glucocorticoid receptors. The presence of glucocorticoid receptors in liver has been reported in many mammalian species but not in nude mice. In the present study, we demonstrate the presence of specific glucocorticoid receptors in nude mouse liver. The binding of ligands to these receptors could be completely inhibited by RU486, and partially blocked by hydrocortisone and progesterone, whereas estrogen and testosterone had no effect. Hydrocortisone downregulated the level of glucocorticoid receptors in livers of nude mice and correspondingly enhanced the activities of tyrosine aminotransferase and gamma-glutamyltransferase. Our results indicate that glucocorticoid receptors in nude mouse liver are specific, fully functional, and present at levels 28.5-fold higher than in the liver of normal inbred mice. We suggest that the nude mouse is a valuable model for studies of hepatic glucocorticoid action and may provide a clue to a putative hepatic-thymic interaction. Copyright 1994 S. Karger AG, Basel

Detection of human androgen receptor mRNA in hepatocellular carcinoma by in situ hybridisation

Recent evidence suggests that anti-androgen therapy may be useful in patients with androgen receptor (AR)-positive hepatocellular carcinomas (HCC), as determined by a steroid binding assay. To evaluate the AR expression of HCC, in both histological and cytological material, we developed a non-radioisotopic in situ hybridisation (NISH) assay specific for the human AR mRNA. A synthetic oligonucleotide complementary to positions 661-695 of the human AR coding sequence was end-labelled with digoxigenin-dUTP and revealed by an alkaline phosphatase-conjugated anti-digoxigenin antibody. We analysed 22 formalin-fixed, paraffin-embedded HCC, obtained at surgery, together with the corresponding non-neoplastic liver tissues (19 cases). In six cases, cell blocks obtained by fine-needle aspiration (FNA) prior to surgery were also available. Positive controls included seminal vesicles and prostate tissues. Sixteen HCCs (73%) expressed a variable amount of AR mRNA, with the proportion of positive cells ranging from very few to more than 90%. Normal hepatocytes were stained weakly and focally in eight cases (42%). Appropriate controls, inclusive of immunohistochemical detection of the AR protein in selected cases, established the specificity of the assay. Data obtained on FNA specimens were predictive of the results on histologic material. However, in two cases the NISH assay was negative on the cytological specimen but stained rare hepatocytes within the surgically resected tumor. In conclusion, NISH is a novel procedure for rapid and specific assessment of the expression of AR in HCC tissue. Its clinical significance, in terms of predictivity of response to anti-androgen treatment, needs to be assessed in large correlative studies.

Effect of antiandrogen treatment on chemical hepatocarcinogenesis in rats

We studied the effect of antiandrogen treatment on the Solt-Farber model of hepatocarcinogenesis in male Sprague-Dawley rats. The size and number of the liver tumors were reduced by various antiandrogen treatments (orchiectomy, an LH-RH analog, and chlormadinone acetate). In addition, the proportion of poorly differentiated carcinomas was decreased by the antiandrogen treatment, while that of well-differentiated trabecular or glandular carcinomas was increased. The bromodeoxyuridine labeling index of the tumor cells was significantly decreased after the antiandrogen treatment. The expression of rat androgen receptor mRNA in carcinoma tissue was increased when compared to control liver tissue, and was decreased after the antiandrogen treatment. Orchiectomy had the greatest inhibitory effect on carcinoma, although the effect of chemical orchiectomy using an LH-RH analog was almost similar to that of orchiectomy. These results suggest that the clinical application of antiandrogen therapy for human hepatocellular carcinoma might be possible in the future.

A risk-benefit assessment of tamoxifen therapy

Tamoxifen is the endocrine treatment of choice for all women with hormonally responsive breast cancer. 30 years of experience in both the laboratory and clinical setting have shown tamoxifen to be an effective adjuvant treatment with minor short term adverse effects. However, as therapeutic use has extended to 5 years and beyond, and as clinical trials begin which will assess the effectiveness of tamoxifen as a preventive treatment, concern about possible long term adverse effects is justified. Tamoxifen has an estrogen-like influence on the skeletal and cardiovascular systems, resulting in decreases in both postmenopausal bone loss and low density lipoprotein (LDL) levels. These effects will, it is hoped, result in decreases in the incidences of osteoporosis and coronary heart disease, which are major causes of morbidity and mortality in the postmenopausal age group. Tamoxifen therapy also results in decreased rates of contralateral breast cancer. Long term tamoxifen treatment may result in a small increase in the incidence of endometrial and/or hepatocellular carcinoma, but with millions of women taking tamoxifen for long periods, such small increases in incidence translate to a significant number of women at risk. Tamoxifen is clearly beneficial for short term treatment, but the clinical decision of tamoxifen use in the long term must be made on the individual benefits versus risks of tamoxifen treatment.

Hepatic cytosolic oestrogen receptors in patients with liver disease

Patients with liver disease present many of the features of 'feminized' hepatic metabolism. Oestrogens exert their effects through interaction with specific cellular high-affinity receptors (ER). We measured hepatic ER in 102 needle biopsies from patients with chronic alcoholic and non-alcoholic liver disease using an enzyme immunoassay. Fifteen patients with no or minimal changes in liver histology served as controls. The hepatic ER concentrations were significantly (P = 0.05) lower in the 44 men (median 13 fmol mg-1 protein, interquartile range 7-17 fmol mg-1 protein) compared to the 58 women (median 15 fmol mg-1 protein, interquartile range 10-21 fmol mg-1 protein). Patients with alcoholic liver disease (n = 63) had significantly (P < 0.05) lower ER concentrations than controls (n = 15) (median 13 fmol mg-1 protein, interquartile range 7-17 fmol mg-1 protein vs. median 16 fmol mg-1 protein, interquartile range 10-26 fmol mg-1 protein), and compared with patients with non-alcoholic liver disease (n = 24) (P < 0.05, median 20 fmol mg-1 protein, interquartile range 11-24 fmol mg-1 protein). ER concentrations were significantly lower (P < 0.05) in patients with alcoholic liver disease and alcoholic hepatitis (n = 21) compared to those without alcoholic hepatitis (n = 42) (medians 10 vs. 14 fmol mg-1 protein, interquartile ranges 6-15 fmol mg-1 protein vs. 9-18 fmol mg-1 protein), while ER concentrations did not differ significantly (P > 0.05) between actively drinking (median 13 fmol mg-1 protein, interquartile range 7-17 fmol mg-1 protein) and abstaining alcoholic patients (median 13 fmol mg-1 protein. interquartile range 7-18 fmol mg-1 protein). In summary, the small but significant variation in hepatic ER concentrations reflects variation in liver function rather than an effect of ethanol.

Sex hormone receptors in hepatocellular carcinoma. Is there a rationale for hormonal treatment?

The present study assessed the tumor concentration of receptors for estrogens, progesterone and androgens in a series of Western patients with hepatocellular carcinoma. Receptors for estrogens and for progesterone were determined by enzyme immunoassay, while androgen receptors were determined by receptor binding assay. Receptors for progesterone were always absent. Estrogen receptors were detected in only 4 tumors, while in the remaining specimens estrogen receptor concentration was lower than 5 fmol/mg of protein. The concentration of receptors within the tumor was not related to the presence of receptor in the non-tumoral liver, which contained estrogen receptors in 12 cases, ranging between 5 and 27 fmol/mg of protein. In contrast, 14 of the 26 tumors contained androgen receptors at concentrations ranging between 2 and 211 fmol/mg of protein; these were not related to the characteristics of the underlying liver, which contained androgen receptors in 14 cases. The results suggest that the beneficial effects of tamoxifen on the survival of patients with hepatocellular carcinoma cannot be explained by the action of this drug on estrogen receptors and that anti-androgen therapy may have some benefit in patients with androgen-receptor-positive tumors.

Aromatase activity in human hepatocellular carcinoma. Relationship with the degree of histologic differentiation

Human hepatocellular carcinomas (HCC) were examined aromatase activity, an enzyme that converts androgen into estrogen. Such activity was detected in all 13 specimens of HCC (mean activity, 120 fmol/30 min/mg microsomal protein). The activity tended to be lower in the HCC tissue than in the surrounding liver tissue (mean activity, 230 fmol/30 min/mg microsomal protein), although it was higher in the HCC tissue from three of eight patients with Edmondson's Grade 2 disease. This relationship was not found in the five with Grade 3 disease. On the whole, aromatase activity was significantly higher in specimens from patients with Edmondson's Grade 2 tumors than in the less differentiated Grade 3 type (P < 0.05). These observations suggested that aromatase activity was present in human HCC and was related to the degree of histologic differentiation.

Expression of estrogen receptor mRNA in tumorous and non-tumorous liver tissue as detected by in situ hybridization

Estrogen receptor mRNA was detected by a non-radioactive in situ hybridization assay in tumor and non-neoplastic liver tissues. A synthetic oligonucleotide complementary to the human estrogen receptor mRNA was 3'-labeled with digoxigenin-deoxyuridine triphosphate (dUTP). Hybrids were revealed by an alkaline phosphatase-conjugated anti-digoxigenin antibody. Fourteen primary hepatocellular carcinoma tissues (and one metastatic) were obtained at surgery from 15 patients. The corresponding non-neoplastic liver tissues were available in 13 cases. The estrogen receptor mRNA was detected in 11 tumorous and 7 non-tumorous liver specimens. The staining was cytoplasmic and involved the majority of transformed hepatocytes, whereas a less widespread and weaker signal was found in normal hepatocytes. Within non-neoplastic tissue, bile duct epithelial cells could also be occasionally stained, whereas other cell types, such as vasal endothelial cells, were negative. Appropriate controls established the specificity of the reaction. Detection of the estrogen receptor protein by immunohistochemistry in these same specimens was invariably negative. This in situ hybridization assay can therefore be used as a complementary tool to evaluate the estrogen receptor expression within liver cancer.

Non-surgical treatment of hepatocarcinoma

Hepatocellular carcinoma (HCC) is one of the most common tumors affecting man. It is the general feeling that only hepatectomy can give a chance for cure. However, less than 20% of patients can be resected, and other treatment modalities are required. Systemic (chemotherapy, hormonotherapy, immunotherapy) and loco-regional (intratumoral injection of alcohol, intra-arterial chemotherapy embolization, internal radiotherapy) approaches have been developed. In view of the small number of patients, tumor and patient heterogeneity, and difficulties in assessing tumor response, the real place of these treatments is difficult to evaluate. A review of the literature suggests that embolization with Gelfoam, even when given without chemotherapy, has an effect on response rate and on survival, and could be considered, at the present time, as the most attractive treatment in non-operable HCC. Chemotherapy seems effective only if combined with embolization. When administered alone by the systemic or the intra-arterial hepatic route, no clinically significant activity can be found. Unexpectedly, Lipiodol by itself seems inactive, and the co-administration of chemotherapy does not improve activity. Other approaches such as intratumoral injection of alcohol, immunotherapy, hormonotherapy, and radioimmunotherapy are still experimental, and well-designed studies are needed to identify their role.

Hepatitis B virus infection and primary hepatocellular carcinoma

For many years, epidemiological studies have demonstrated a strong link between chronic hepatitis B virus (HBV) infection and the development of primary hepatocellular carcinoma (PHC). Other hepatocarcinogens such as hepatitis C virus and aflatoxin also contribute to hepatocarcinogenesis either in conjunction with HBV infection or alone. Cellular and molecular biological studies are providing explanations for the HBV-PHC relationship, and models are now being formulated to further test the relative importance of various factors such as viral DNA integration, activation of oncogenes, genetic instability, loss of tumor suppressor genes, and trans-activating properties of HBV to the pathogenesis of PHC. Further research will probably define more than a single mechanism whereby chronic HBV infection results in PHC.

Hormonal therapy for hepatocellular carcinoma

Hepatocellular carcinoma is not only the leading cause of male cancer death in Taiwan, but also one of the most common cancers in the world. The survival of hepatocellular carcinoma patients is very low, mainly due to the lack of effective treatments. Radiation and chemotherapies in general are not satisfactory: surgery itself is the most effective treatment for hepatocellular carcinoma but only on small resectable tumors. The overall prognosis is still poor. Previously, we have found that the level of glucocorticoid receptor and its mRNA in hepatocellular carcinoma was significantly higher than that of the adjacent liver tissue. This correlated well with the elevated serum alpha-fetoprotein levels in patients with hepatocellular carcinoma. Recently, a female hormone, progesterone, has been found to inhibit the expression of alpha-fetoprotein in hepatoma cells. In addition, progesterone has been used to treat a few hepatocellular carcinoma patients with promising responses. These results together with our hypothesis that the expression of alpha-fetoprotein is regulated by glucocorticoid receptor complex in proliferating hepatocellular carcinoma cells lead to the conclusion that steroid hormones and/or their antagonists may interfere with the function of glucocorticoid receptors in tumors, consequently regulate tumor growth. The potential of hormonal therapy for treatment of hepatocellular carcinoma is worthy of further investigation.

Enzyme immunoassay of oestrogen receptors in needle biopsies from human liver

For quantitative assessments of sex hormone receptors in liver tissue, ligand binding assays are inconvenient, as they require large biopsies (0.5-1.0 g). The present study shows that it is possible to measure oestrogen receptors (ER) quantitatively in needle biopsy specimens as small as 10 mg by modifications of a commercial enzyme immunoassay employing monoclonal antibodies. Sucrose gradient centrifugation and the dextran charcoal method served as reference methods. A consecutive series of needle biopsies from patients suspected of liver disease were investigated. The biopsies (n = 37) had a median weight of 14 mg and cytosolic protein concentrations greater than 1 mg/ml (median 1.28 mg/ml). The median ER concentration was 20 fmol/mg cytosolic protein (range 5 to 57 fmol/mg). The intra-assay coefficient of variation was 8.9%, the inter-assay 13.2%, and the detection limit 2.7 fmol/ml cytosol. Women had significantly higher ER concentrations (median 22 fmol/mg) compared to male patients (median 16 fmol/mg) (P = 0.007). The enzyme immunoassay measures ER in liver specimens as small as 10 mg, compared to the large tissue specimens necessary for the conventional DCC assay, and the method is a convenient tool for further studies of ER in routine needle biopsies from the liver.

Quantitation of estrogen and androgen receptors in hepatocellular carcinoma and adjacent normal human liver

Sex hormones have been shown to influence the development and course of several liver diseases. The worldwide predominance of hepatocellular carcinoma (HCC) in males has led to the suggestion that this disease might be hormone-responsive. Therefore, the hepatic estrogen (ER) and androgen receptor (AR) status of liver specimens from such patients was investigated. Samples were obtained from three female and six males patients undergoing liver resection; in each case, a small sample of both the tumor and adjacent normal tissue was collected. All patients had primary hepatocellular carcinoma without cirrhosis. In most cases, the tumor and the normal specimen had an equivalent content of cytosolic ER; however, three of the tumor samples (one female and two male) displayed considerably elevated cytosolic ER levels as compared to that of the normal tissue. In every sample, the tumor contained less nuclear ER than did the normal liver. When AR was measured, tumors of three patients (one female and two male) demonstrated a twofold elevation in cytosolic AR as compared to adjacent normal tissue. In the two male patients, an approximately twofold greater nuclear AR was found. Two other samples from male patients showed a modest elevation of cytosolic AR in the tumors. The patients whose tumors showed elevations in ER were not the same patients as those in whom the AR was elevated. Thus, these studies indicate that certain, but not all, specimens of HCC demonstrate either elevated ER or AR and suggest that a determination of receptor content might be useful prior to initiation of certain antihormone therapies.

Advances in neoplastic disease of the liver and biliary tract

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Hepatocellular carcinoma. A worldwide problem and the major risk factors

Male sex, age, cirrhosis, and HBsAg are the major risk factors for hepatocellular carcinoma (HCC). The geographic distribution of HCC is highly uneven, such that three distinct incidence areas are recognized. To clarify the reason(s) for this geographic variability of HCC, the risk factors in each incidence area were assessed. In parallel with the geographic distribution of HCC, HBsAg prevalence was highest in both HCC patients and in general population in Africa and Asia, where mothers of HCC patients are frequently HBsAg-positive, suggesting that hepatitis B virus hyperendemicity and perinatal infection account for the high HCC incidence in these areas. Cirrhosis, which is found on autopsy in 80% of the cases of HCC patients worldwide, is the most prevalent risk factor for HCC in areas where hepatitis B virus infection is less common. However, HBsAg carriage adds to the HCC risk carried by cirrhosis and explains the higher incidence of HCC in cirrhotics from Africa and Asia as well as elsewhere. Available data suggest that chronic HCV infection is a risk factor for cirrhosis and HCC. HBV vaccination should decrease HCC incidence rates worldwide; however, HCC prevention in regions where HBsAg carriage is infrequent may also require prevention of the other causes of cirrhosis in order for HCC rates to decline.

Expression of androgen receptor mRNA in human hepatocellular carcinomas and hepatoma cell lines

The expression of androgen receptor messenger RNA in hepatocellular carcinomas and hepatoma cell lines was studied using Northern-blot analysis and the complementary DNA-polymerase chain reaction method. Androgen receptor messenger RNAs were detected (although in low levels) in both hepatocellular carcinoma tissues and noncancerous tissues of the liver in all eight cases we studied, except for the tumor sample of one case. None of the hepatoma cell lines studied, however, expressed detectable levels of androgen receptor messenger RNA except for the SK-HEP-1 hepatoma cell line.

Growth factors, endocrine aspects and hormonal treatment in hepatocellular carcinoma--an overview

Several clinical observations suggest that hepatocellular carcinoma (HCC or "hepatoma") may be a hormone-dependent tumour; the apparent relation to anabolic steroids and oral contraceptive preparations, and the striking male predominance particularly among patients with cirrhosis. In many animal models thyroid hormones, prolactin and testosterone stimulate tumour growth, and the latter may enhance the progression of chemically-induced hyperplastic nodules to frank malignancy. In animals and humans, both oestrogen and androgen receptors have been reported in normal and malignant liver tissue though some of the evidence is conflicting and the amounts detected vary widely. From a therapeutic standpoint, we failed to show any advantage from the addition of tamoxifen to adriamycin, in a controlled trial although other workers have, more recently, reported prolonged survival using tamoxifen alone. About 20% of HCC patients receiving the antiandrogen cyproterone acetate showed a clinical response.

Estrogen and androgen regulation of sex hormone binding globulin secretion by a human liver cell line

Both estrogens and androgens have been shown to stimulate sex hormone binding globulin (SHBG) secretion in vitro in the hepatocellular carcinoma cell line, Hep G2, in contrast to the expected inhibition by androgens from in vivo studies. However, such in vitro stimulation was only demonstrated at high steroid doses, generally in serum-containing medium, with added Phenol Red. In the present study, Hep G2 cells were grown in serum-free medium, without Phenol Red, under the influence of testosterone (T) (0, 0.5-500 nM) and ethinyl estradiol (EE2) (0, 50 pM-500 nM). Levels of secreted SHBG and albumin were correlated with androgen receptors in cytosolic (ARc) and nuclear (ARn) fractions and with DNA levels. In the presence of increasing T levels, SHBG levels fell to 39% of control values at 5 nM T (P = 0.047), rising to 97% of control at 500 nM. Conversely, incubation with EE2 produced a rise in SHBG secretion of more than 100% at 0.5 nM (P less than 0.02) which was sustained to 50 nM (P less than 0.005). DNA levels did not change with the addition of testosterone or EE2, with the exception of a 15% reduction at 5 nM EE2 (P less than 0.05). Albumin levels in the medium were not significantly altered by either steroid. However, in response to T, androgen receptor (AR) levels were reduced in cytosolic (42% of control) and nuclear (22%) fractions at 5 nM, and these changes in ARc and ARn correlated with SHBG levels over the range of T concentrations (P = 0.04 and P = 0.017, respectively). Nuclear estrogen receptor (ER) increased over 10-fold at 5 and 50 pM EE2 (P less than 0.001) and maintained 50 nM (P less than 0.001). Cytosolic ER was reduced at 0.5 and 5 nM but recovered at 50 nM, correlating with SHBG levels (P less than 0.001). These findings are consistent with the hypothesis that estrogens and androgens regulate SHBG synthesis in man by direct, specific, probably receptor-mediated effects on hepatocytes. Hep G2 cells grown in serum-free medium are a suitable experimental system for further study of this phenomenon.

Hepatocellular carcinoma with cardiac cirrhosis

Hepatocellular carcinoma is a recognized complication of hepatic cirrhosis, most commonly associated with alcohol excess, haemochromatosis and chronic hepatitis B infection. Long-standing hepatic venous congestion may cause cirrhosis. A search of the literature has not revealed a case of hepatocellular carcinoma complicating cardiac cirrhosis. A case is described and the association is discussed.

Effect of D-tryptophan-6-luteinizing hormone-releasing hormone on the tumoral growth and plasma sex steroid levels in cirrhotic patients with hepatocellular carcinoma

Certain evidence suggests androgen dependence of hepatocellular carcinoma in cirrhotic patients. Consequently, it was postulated that antiandrogen therapy might be effective in the treatment of hepatocellular carcinoma. D-Tryptophan-6-luteinizing hormone-releasing hormone is a potent agonist analog of luteinizing hormone-releasing hormone which, when chronically administered, inhibits the pituitary gonadal axis and testicular androgen secretion in man. We studied the effects of D-tryptophan-6-luteinizing hormone-releasing hormone on tumoral growth in 17 male cirrhotic patients with hepatocellular carcinoma. After 3 to 6 months of therapy, no tumoral response was observed. Furthermore, measurements of plasma levels of testosterone, dihydrotestosterone, androstenedione, estradiol, estrone and sex hormone-binding globulin were performed before and 3 months after initiation of the antiandrogenic treatment. Before treatment, hypoandrogenism and hyperestrogenism were present; D-tryptophan-6-luteinizing hormone-releasing hormone induced a fall in plasma testosterone and dihydrotestosterone levels. Only a moderate decrease in estradiol and no modification of plasma estrone and sex hormone-binding globulin were found, indicating that the hyperestrogenemia of cirrhotic patients could be attributed to an increase in peripheral aromatization of androgens of adrenal origin. The inability of D-tryptophan-6-luteinizing hormone-releasing hormone to reduce the growth of hepatocellular carcinoma is not totally in disagreement with the concept of androgen dependence of hepatocellular carcinoma since D-tryptophan-6-luteinizing hormone-releasing hormone does not inhibit the production of androgens of adrenal origin.

Age and sex differences in bone metastasis of hepatocellular carcinoma in Japanese autopsy cases

Metastatic patterns of hepatocellular carcinoma (HCC) in 6997 autopsy cases recorded in the Annual of the Pathological Autopsy Cases in Japan from 1981 to 1984 were analyzed by using a computer. Significant association of the metastatic pattern of hepatocellular carcinoma with age and sex was shown after separating patients into different age groups in pack years. It was especially worthy of notice that bone metastasis decreased in an age-dependent manner only in men within the widest age range (P less than 0.001) and was significantly prevalent in men in their forties and fifties (P = 0.012). In addition, in 350 cases of hepatocellular carcinoma autopsied at Tokyo University Hospital during 15 years from 1971 to 1985, it was suggested that bone metastasis might be prevalent in male patients with liver cirrhosis although significant relationship between bone metastasis and hepatitis B virus infection or alcohol abuse was not shown. These results might indicate possible effects of sex differences on the metastatic pattern of hepatocellular carcinoma, particularly bone metastasis, as well as on the incidence of the cancer.

The effect of several sex steroid hormones on the growth rate of three Morris hepatoma tumor lines

Morris hepatoma 44, whose growth is sensitive to thyroid hormones and prolactin, contains specific receptors for these hormones. In the present experiments, male Buffalo rats bearing Morris hepatoma 7787 were studied to determine the effects of several sex steroid hormones. Castration 1 week postimplantation inhibited tumor growth relative to controls (-53%). Replacement with testosterone propionate (1 mg per day s.c. injection) restored tumor growth to control levels, whereas administration of testosterone (2 mg per day s.c. injection) to castrated controls resulted in significant stimulation. Testosterone administered to control animals at a dose of 1 mg per day stimulated tumor growth (62%), whereas 2 mg per day failed to do so. Progesterone (4-pregnon-3,20-dione) at doses of 125 or 250 micrograms per day (Silastic implants) had no effect on tumor growth, whereas 500 micrograms per day stimulated tumor growth relative to controls. Estrogen (17 beta-estradiol) at doses of 6, 12, or 24 micrograms per day (Silastic implants) did not influence tumor growth. Cytoplasmic testosterone receptors have been demonstrated in tumors (2.2 +/- 0.8 fmoles per mg cytoplasm), although specific cytoplasmic estrogen and progesterone receptors could not be identified in this model. In female rats bearing either Morris hepatoma 44, 7787 or 5123-D, testosterone markedly stimulated tumor growth (226, 328 and 58%, respectively, relative to controls). In conclusion, although Morris hepatoma 7787 appears to be androgen (testosterone) dependent and contains cytoplastic androgen receptors, it lacks specific cytoplasmic receptors for estrogen and progesterone and is not influenced by these hormones except at very high doses of progesterone.

Androgen receptor in hepatocellular carcinoma as a prognostic factor after hepatic resection

Androgen receptors (AR) in the cytosol of hepatocellular carcinoma (HCC) were assayed in 45 unselected patients in whom radical hepatic resection was performed. Thirty-one patients had detectable amounts of ARs in tumors, ranging from 2.3 to 82.6 fmol/mg protein with the dissociation constants (Kd) of 4.1 - 30.9 x 10(-10) M. The receptor was not found in the remaining 14 cases. AR negative HCCs were significantly more common among women and nonalcoholic patients. Otherwise, there were no significant difference in the clinicopathologic background between patients with AR positive HCCs and those with AR negative tumors. Three patients died of liver failure in the former group, whereas two died in the latter; one patient died of liver failure and the other died of pneumonia (results were not statistically significant). Excluding those five operative deaths, the recurrence rates were 67.9% in the group of patients with AR positive HCCs and 33.3% in the group of patients with AR negative tumors (0.1 less than p less than 0.05). The 5-year survival rate was significantly better (p less than 0.05) in patients with AR negative HCCs (62.2%) than in those with the positive tumors (17.3%). In light of the current results and previous experimental works by others, it is likely that testosterones enhance the growth and invasiveness of human HCC, which is mediated by AR in the tumor.

Glucocorticoid receptors in hepatocellular carcinoma and adjacent liver tissue

Glucocorticoid and progesterone receptors, tyrosine aminotransferase, gamma-glutamyltransferase and alpha-fetoprotein levels were determined in human hepatocellular carcinoma (HCC) and adjacent liver tissues. Glucocorticoid receptor was present in seven of ten HCC samples, values ranged from 1.9 to 66.8 fmol/mg protein. Progesterone receptor was present in two of ten HCC samples with values of 1.7 and 7.2 fmol/mg protein, respectively. In the adjacent liver tissues, no measurable progesterone receptor was found and only one sample had glucocorticoid receptor with a value of 3.0 fmol/mg protein. The increase of glucocorticoid receptor in HCC samples was coincident with a decreased level of tyrosine aminotransferase and an increased level of gamma-glutamyltransferase. No correlation was found among glucocorticoid receptor level, serum or tissue alpha-fetoprotein levels. The presence of glucocorticoid receptors in HCC suggest that hormones may play an important role in the formation of hepatoma, and hormonal therapy may be useful for patients with HCC.

Hepatoma in the noncirrhotic liver

The pathologic features, clinical presentation and natural history of hepatocellular carcinoma (HCC) developing in the noncirrhotic liver were studied in 61 patients against a background of 63 patients seen concurrently with HCC complicating cirrhosis. Noncirrhotic HCC had a bimodal age distribution, with females predominating the first age-clustering (10-50 years) and males predominating the second age-clustering (50-90 years). Cirrhotic HCC had a unimodal age distribution (40-90 years) with male dominance throughout. Estrogen exposure was noted in 57% of the noncirrhotic HCC women overall and in 80% of those in the younger age-clustering. The majority of noncirrhotic HCC presented with a single hepatic mass or a dominant primary with satellite lesions in contrast to the usual multinodular or diffuse disease seen with cirrhosis. Twenty-nine noncirrhotic patients survived complete resection of disease limited to the liver and exhibited a median survival of 2.7 years with a 5-year survival of 25%. Low histologic grade, minimal necrosis, and the absence of hemoperitoneum, hepatomegaly, and adjacent organ involvement were all favorable prognostic variable. Patients with metastatic or locally unresectable noncirrhotic HCC had a median survival of 9 months, and 24% survived in excess of 2 years. This survival experience is significantly more favorable than cirrhotic HCC patients, who had only a 1.2-month median and a 3% 2-year survival. Low histologic grade, mild mitotic activity and the presence of some fibrosis within the specimen were associated with a favorable outcome in advanced noncirrhotic HCC. The favorable prognosis and heterogeneous composition of the noncirrhotic, when compared to the cirrhotic HCC cohort, may be important considerations in the design and evaluation of future clinical trials.

Review: the treatment of hepatocellular carcinoma

Surgical resection offers the only realistic hope of cure in hepatocellular carcinoma (HCC) but is usually not possible, either because the tumour is widespread throughout the liver at diagnosis, or because liver function is adversely affected by concomitant cirrhosis. The results of operation in early asymptomatic disease are, however, encouraging and efforts should be made to screen regularly the cirrhotic population at risk of HCC development. The prognosis for inoperable patients remains gloomy, though exciting new treatment methods exist which require extensive evaluation. An anthracycline given as single agent intravenous therapy is probably the current treatment of choice for inoperable patients, though only 20-30% will show a response. Intra-arterial therapy has not yet been convincingly shown to have any advantages over intravenous therapy. The evaluation of clinical trials in HCC would be made easier if response criteria were standardized and universally adopted, and if trials were properly controlled and of sufficient sample size to test adequately the hypothesis in question. This review deals only with the specific treatment of HCC. HCC prevention, the early diagnosis of HCC, and the relief of symptoms in HCC, though areas of obvious importance, are outside the scope of this review.

Increased hepatic androgen receptor expression in female rats during diethylnitrosamine liver carcinogenesis. A possible correlation with liver tumor development

This study investigated the relationship between liver tumor development and androgen-receptor expression in diethylnitrosamine hepatocarcinogenesis in Wistar rats (SUAH substrain). Random liver samples were assayed by an isoelectric focusing method, with [3H]mibolerone as androgenic radioligand. After 16 wk of oral diethylnitrosamine treatment there was a greater than 20-fold increase in hepatic androgen receptor concentration in female rats (control group 0.3 +/- 0.07 fmol/mg cytosol protein; test group 8.36 +/- 0.96 fmol/mg cytosol protein; p less than 0.001, unpaired Student's t-test). This coincided with, and may be related to, an accelerated development of neoplastic nodules or hepatocellular carcinoma, or both. Male rats showed slower tumor development and no change in androgen receptor concentrations. This model is the first to demonstrate significantly increased androgen sensitivity in experimental hepatic carcinogenesis analogous to increased androgen receptor expression in human hepatocellular carcinoma. It may provide insight into steroid hormone sensitivity in developing tumors, and a means of testing potential therapeutic use of hormonal manipulation in human liver cancer.

Human hepatocellular carcinoma tumor xenografts. Their androgen-receptor status and growth responses to castration

Castrated or sham-operated male athymic mice were inoculated with cells from the human hepatocellular carcinoma cell line PLC/PRF/5. There were no significant differences between the two groups with respect to the number of animals developing tumors, the time to tumor development, or the subsequent rate of increase in either tumor base area or mouse serum alpha-fetoprotein concentration. Androgen receptors were assayed in nuclei obtained from three separate liver cancer cell lines and from normal adult human liver. Similar concentrations, ranging from 235 to 550 fmol/mg DNA, of nuclear androgen receptors were detected in all tissues. Low percentages of androgen receptors were retained on DNA-cellulose. Although the presence of receptors implies the potential for metabolic effects of androgens in normal and malignant liver, our in vivo studies suggest that castration does not alter significantly the growth of liver cancer xenografts in athymic mice.

Liver tumours

Humans are remarkably resistant to many carcinogens that readily produce liver tumours in rodents, particularly the rat. The neoplastic process has been extensively studied in animal experiments, but little is known so far of how it evolves in humans. Few drugs have been shown to cause liver tumours in humans, and the risk appears to be low. The best-known examples are C17-alkylated or ethinylated gonadal sex steroids. Oral contraceptives have now been in use by millions for thirty years, but only a few hundred cases at most of liver cell adenoma have been observed. The role of these substances in liver cell carcinoma remains controversial, and the evidence is weaker still in relation to focal nodular hyperplasia and other tumour-like conditions. Anabolic-androgenic steroids stand out as the major cause of peliosis, but liver cell tumours induced by them seem to be adenomas and not carcinomas as originally suggested. The effect that both oral contraceptives and anabolic-androgenic steroids have on liver vasculature is of great clinical importance as the most important complication of liver tumours is rupture, leading to life-threatening haemorrhage. For this reason, liver tumours arising in users of these drugs should be removed whenever feasible. Thorium dioxide will remain a risk factor for the development of angiosarcoma, liver cell carcinoma and bile duct carcinoma for some time yet, and the number of patients who have been exposed is high--tens of thousands at least. The evidence of a carcinogenic role for many other drugs is anecdotal or weak. Neoplasia in the liver seems to be the least important side-effect of drugs in clinical use.