Upregulation of Glypican-3 expression in hepatocellular carcinoma but downregulation in cholangiocarcinoma indicates its differential diagnosis value in primary liver cancers

Secular Trends of Liver Cancer Mortality and Years of Life Lost in Wuhan, China 2010-2019

BACKGROUND

Liver cancer has caused a heavy burden worldwide. This study aimed to estimate the trends in the mortality and years of life lost (YLL) due to liver cancer and decompose the total deaths into three contributors: population growth, population aging, and mortality change.

METHODS

Our study used data from the cause-of-death surveillance system in Wuhan. The mortality and YLL rates were standardized according to the sixth national population census in China. This study calculated the estimated annual percentage change (EAPC) to estimate the trends in the age-standardized mortality rate (ASMR) and age-standardized YLL rate (ASYR). Meanwhile, a decomposition analysis was used to explore the effect of population growth, population aging, and age-specific mortality change on the change in liver cancer deaths.

RESULTS

The ASMR of liver cancer declined at an annual rate of 4.6% from 30.87 per 100,000 people in 2010 to 20.29 per 100,000 people in 2019, while the ASYR was at an annual rate of 5.6% from 969.35 per 100,000 people in 2010 to 581.82 per 100,000 people in 2019. Similar downward trends were seen in men and women. The decomposition analysis found that total deaths number changed by -12.42% from 2010 to 2019, of which population growth and population aging caused the total death numbers to increase by 9.75% and 21.15%, while the age-specific mortality change caused the total death numbers to decrease by 43.32%.

CONCLUSION

Although the ASMR of liver cancer has declined in recent years in Wuhan, it still causes a heavy burden with the increasing population and rapid population aging and remains an essential public health issue. The government should take measures to reduce the burden of liver cancer, especially among men.

Panel of potential lncRNA biomarkers can distinguish various types of liver malignant and benign tumors

PURPOSE

Liver cancers are among the deadliest malignancies due to a limited efficacy of early diagnostics, the lack of appropriate biomarkers and insufficient discrimination of different types of tumors by classic and molecular methods. In this study, we searched for novel long non-coding RNA (lncRNA) as well as validated several known candidates suitable as probable biomarkers for primary liver tumors of various etiology.

METHODS

We described a novel lncRNA HELIS (aka "HEalthy LIver Specific") and estimated its expression by RT-qPCR in 82 paired tissue samples from patients with hepatocellular carcinoma (HCC), cholangiocarcinoma (CCA), combined HCC-CCA, pediatric hepatoblastoma (HBL) and non-malignant hepatocellular adenoma (HCA) and focal nodular hyperplasia (FNH). Additionally, we examined expression of cancer-associated lncRNAs HULC, MALAT1, UCA1, CYTOR, LINC01093 and H19, which were previously studied mainly in HCC.

RESULTS

We demonstrated that down-regulation of HELIS strongly correlates with carcinogenesis; whereas in tumors with non-hepatocyte origin (HBL, CCA) or in a number of poorly differentiated HCC, this lncRNA is not expressed. We showed that recently discovered LINC01093 is dramatically down-regulated in all malignant liver cancers; while in benign tumors LINC01093 expression is just twice decreased in comparison to adjacent samples.

CONCLUSION

Our study revealed that among all measured biomarkers only down-regulated HELIS and LINC01093, up-regulated CYTOR and dysregulated HULC are perspective for differential diagnostics of liver cancers; whereas others demonstrated discordant results and cannot be considered as potential universal biomarkers for this purpose.

The Role of Proteoglycans in Cancer Metastasis and Circulating Tumor Cell Analysis

Circulating tumor cells (CTCs) are accessible by liquid biopsies via an easy blood draw. They represent not only the primary tumor site, but also potential metastatic lesions, and could thus be an attractive supplement for cancer diagnostics. However, the analysis of rare CTCs in billions of normal blood cells is still technically challenging and novel specific CTC markers are needed. The formation of metastasis is a complex process supported by numerous molecular alterations, and thus novel CTC markers might be found by focusing on this process. One example of this is specific changes in the cancer cell glycocalyx, which is a network on the cell surface composed of carbohydrate structures. Proteoglycans are important glycocalyx components and consist of a protein core and covalently attached long glycosaminoglycan chains. A few CTC assays have already utilized proteoglycans for both enrichment and analysis of CTCs. Nonetheless, the biological function of proteoglycans on clinical CTCs has not been studied in detail so far. Therefore, the present review describes proteoglycan functions during the metastatic cascade to highlight their importance to CTCs. We also outline current approaches for CTC assays based on targeting proteoglycans by their protein cores or their glycosaminoglycan chains. Lastly, we briefly discuss important technical aspects, which should be considered for studying proteoglycans.

Sorafenib encapsulated in nanocarrier functionalized with glypican-3 specific peptide for targeted therapy of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common cancer in the world with increasing incidence. Chemotherapy is required for HCC patients after receiving surgical resection. Serious off-target induced side effects and systemic toxicity limit the clinical utility of drugs. Targeting therapeutic nanomedicine is an innovative strategy for enhancing drug delivery efficiency and reducing side effects. Here, we successfully formulated nanocarriers to encapsulate sorafenib, an FDA approved drug for treatment of HCC. Sorafenib is encapsulated with an entrapment efficiency >80% over 20 days. The effective aqueous solubility is improved over 1900-fold. The release ratio in vitro is characterized by a half-life of T_1/2 = 22.7 h. The peak target-to-background ratio for nanocarrier uptake by tumor occurs at 24 h post-injection, and is significantly greater for the target peptide versus controls. Ex vivo biodistribution confirms the in vivo results. Tumor regression is significantly greater for the target peptide versus controls after 21 days of therapy. No acute toxicity is found by blood chemistry or necropsy. In summary, a peptide specific for GPC3 has been identified, and used to modify the surface of a nanocarrier that encapsulates sorafenib with high entrapment efficiency. Regression of HCC xenograft tumors showed promise for targeted drug delivery.

Lnc-UCID Promotes G1/S Transition and Hepatoma Growth by Preventing DHX9-Mediated CDK6 Down-regulation

Although thousands of long noncoding RNAs (lncRNAs) have been annotated, only a limited number of them have been functionally characterized. Here, we identified an oncogenic lncRNA, named lnc-UCID (lncRNA up-regulating CDK6 by interacting with DHX9). Lnc-UCID was up-regulated in hepatocellular carcinoma (HCC), and a higher lnc-UCID level was correlated with shorter recurrence-free survival of HCC patients. Both gain-of-function and loss-of function studies revealed that lnc-UCID enhanced cyclin-dependent kinase 6 (CDK6) expression and thereby promoted G1/S transition and cell proliferation. Studies from mouse xenograft models revealed that tumors derived from lnc-UCID-silenced HCC cells had a much smaller size than those from control cells, and intratumoral injection of lnc-UCID small interfering RNA suppressed xenograft growth. Mechanistically, the 850-1030-nt domain of lnc-UCID interacted physically with DEAH (Asp-Glu-Ala-His) box helicase 9 (DHX9), an RNA helicase. On the other hand, DHX9 post-transcriptionally suppressed CDK6 expression by binding to the 3'-untranslated region (3'UTR) of CDK6 mRNA. Further investigation disclosed that lnc-UCID enhanced CDK6 expression by competitively binding to DHX9 and sequestering DHX9 from CDK6-3'UTR. In an attempt to explore the mechanisms responsible for lnc-UCID up-regulation in HCC, we found that the lnc-UCID gene was frequently amplified in HCC. Furthermore, miR-148a, whose down-regulation was associated with an increase of lnc-UCID in HCC, could bind lnc-UCID and inhibit its expression. Conclusion: Up-regulation of lnc-UCID, which may result from amplification of its gene locus and down-regulation of miR-148a, can promote HCC growth by preventing the interaction of DHX9 with CDK6 and subsequently enhancing CDK6 expression. These findings provide insights into the biological functions of lncRNAs, the regulatory network of cell cycle control, and the mechanisms of HCC development, which may be exploited for anticancer therapy.

Subclassification and Detection of New Markers for the Discrimination of Primary Liver Tumors by Gene Expression Analysis Using Oligonucleotide Arrays

Background/Aims

The failure to correctly differentiate between intrahepatic cholangiocarcinoma (CC) and hepatocellular carcinoma (HCC) is a significant clinical problem, particularly in terms of the different treatment goals for both cancers. In this study a specific gene expression profile to discriminate these two subgroups of liver cancer was established and potential diagnostic markers for clinical use were analyzed.

Methods

To evaluate the gene expression profiles of HCC and intrahepatic CC, Oligonucleotide arrays (AffymetrixU133A) were used. Overexpressed genes were checked for their potential use as new markers for discrimination and their expression values were validated by reverse transcription polymerase chain reaction and immunohistochemistry analyses.

Results

695 genes/expressed sequence tags (ESTs) in HCC (245 up-/450 down-regulated) and 552 genes/ESTs in CC (221 up-/331 down-regulated) were significantly dysregulated (p＜0.05, fold change >2, ≥70%). Using a supervised learning method, and one-way analysis of variance a specific 270-gene expression profile that enabled rapid, reproducible differentiation between both tumors and nonmalignant liver tissues was established. A panel of 12 genes (e.g., HSP90β, ERG1, GPC3, TKT, ACLY, and NME1 for HCC; SPT2, T4S3, CNX43, TTD1, HBD01 for CC) were detected and partly described for the first time as potential discrimination markers.

Conclusions

A specific gene expression profile for discrimination of primary liver cancer was identified and potential marker genes with feasible clinical impact were described.

Evaluating clinical and prognostic implications of Glypican-3 in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most deadly cancers worldwide. In patients with HCC, histopathogical differentiation is an important indicator of prognosis; however, because determination of HCC differentiation is difficult, the recently described immunohistochemical (IHC) marker glypican3 (GPC3) might assist in HCC prognostication.The goal of our study was to investigate GPC3's IHC staining pattern and define the relationship between its expression and patients' clinicopathologic features and overall survival. We retrieved clinical parameters from 101 pathologically diagnosed HCC patients' medical records and classified these patients into 4 clinical score categories (0–3) based on increasing GPC3 staining intensity and the percentage of stained tumor cells in their resection and biopsy specimens. Histopathological samples were well, moderately, and poorly differentiated in 33, 22, and 12 patients, respectively, and the GPC3 expression rate was 63%, 86%, and 92%,respectively. The median overall survival was 49.9 months (confidence interval (CI): 35.3–64.6 months) for clinical scores 0–1 and 30.7 months (CI: 19.4–41.9 months) for clinical scores 2–3. This difference was not statistically significant (P = .06) but showed a strong trend. In conclusion, a greater GPC3 expression is associated with a worse HCC prognosis and may be a promising prognostic marker.

Glypican-3: A promising biomarker for hepatocellular carcinoma diagnosis and treatment

Liver cancer is the second leading cause of cancer-related deaths, and hepatocellular carcinoma (HCC) is the most common type. Therefore, molecular targets are urgently required for the early detection of HCC and the development of novel therapeutic approaches. Glypican-3 (GPC3), an oncofetal proteoglycan anchored to the cell membrane, is normally detected in the fetal liver but not in the healthy adult liver. However, in HCC patients, GPC3 is overexpressed at both the gene and protein levels, and its expression predicts a poor prognosis. Mechanistic studies have revealed that GPC3 functions in HCC progression by binding to molecules such as Wnt signaling proteins and growth factors. Moreover, GPC3 has been used as a target for molecular imaging and therapeutic intervention in HCC. To date, GPC3-targeted magnetic resonance imaging, positron emission tomography, and near-infrared imaging have been investigated for early HCC detection, and various immunotherapeutic protocols targeting GPC3 have been developed, including the use of humanized anti-GPC3 cytotoxic antibodies, treatment with peptide/DNA vaccines, immunotoxin therapies, and genetic therapies. In this review, we summarize the current knowledge regarding the structure, function, and biology of GPC3 with a focus on its clinical potential as a diagnostic molecule and a therapeutic target in HCC immunotherapy.

Biology and function of glypican-3 as a candidate for early cancerous transformation of hepatocytes in hepatocellular carcinoma (Review)

Glypican-3 (GPC-3), a transmembrane heparan sulfate proteoglycan (HSPG), has recently been investigated as a player in tissue-dependent cellular signaling, specifically as a regulator of growth. Noteworthy, the regulatory protein has been implicated in both stimulatory and inhibitory pathways involving cell growth. Initially, GPC-3 was thought to act as a cell cycle regulator, as a loss-of-function mutation in the gene caused a hyper-proliferative state known as Simpson-Golabi-Behmel (SGB) overgrowth syndrome. Additionally, certain cancer types have displayed a downregulation of GPC-3 expression. More recently, the protein has been evaluated as a useful marker for hepatocellular carcinoma (HCC) due to its increased expression in the liver during times of growth. In contrast, the GPC-3 marker is not detectable in normal adult liver. Immunotherapy that targets GPC-3 and its affiliated proteins is under investigation as these new biomarkers may hold potential for the detection and treatment of HCC and other diseases in which GPC-3 may be overexpressed. Studies have reported that an overexpression of GPC-3 in HCC predicts a poorer prognosis. This prognostic value further pushes the question regarding GPC-3's role in the regulation and progression of HCC. This review will summarize the current knowledge regarding the clinical aspects of GPC-3, while also synthesizing the current literature with the aim to better understand this molecule's biological interactions at a molecular level, not only in the liver, but in the rest of the body as well. Due to the existing gap in the literature surrounding GPC-3, we believe further investigation of function, structure and domains, cellular localization, and other subfields is warranted to evaluate the protein as a whole, as well as its part in the study of HCC.

Novel insights into Notum and glypicans regulation in colorectal cancer

The connection between colorectal cancer (CRC) and Wnt signaling pathway activation is well known, but full elucidation of the underlying regulation of the Wnt/β-catenin pathway and its biological functions in CRC pathogenesis is still needed. Here, the azoxymethane/dextran sulfate sodium salt (AOM/DSS) murine model has been used as an experimental platform able to mimic human sporadic CRC development with predictable timing. We performed genome-wide expression profiling of AOM/DSS-induced tumors and normal colon mucosa to identify potential novel CRC biomarkers. Remarkably, the enhanced expression of Notum, a conserved feedback antagonist of Wnt, was observed in tumors along with alterations in Glypican-1 and Glypican-3 levels. These findings were confirmed in a set of human CRC samples. Here, we provide the first demonstration of significant changes in Notum and glypicans gene expression during CRC development and present evidence to suggest them as potential new biomarkers of CRC pathogenesis.

Expression of Markers of Hepatocellular Differentiation in Pancreatic Acinar Cell Neoplasms: A Potential Diagnostic Pitfall

OBJECTIVES

Pancreatic acinar cell carcinoma (ACC) is a rare tumor that frequently metastasizes to the liver and may present a diagnostic challenge due to its morphologic similarity to hepatocellular carcinoma. We investigated α-fetoprotein (AFP), hepatocyte paraffin antigen 1 (HepPar 1), glypican 3, arginase 1, and albumin messenger RNA (mRNA) in situ hybridization (ISH) in pancreatic neoplasms with ACC differentiation to assess their diagnostic value.

METHODS

AFP, HepPar 1, glypican 3, and arginase 1 immunohistochemical staining was performed on 28 ACCs using a tissue microarray. Albumin mRNA ISH was performed on full-faced sections.

RESULTS

Fifteen tumors were positive for at least one marker. Glypican 3 was positive in seven of 28, AFP in five 28, and albumin mRNA ISH in five of 20. None expressed arginase 1.

CONCLUSIONS

Hepatocellular differentiation markers, including albumin mRNA ISH, may be positive in ACC, but arginase 1 appears to be uniformly negative. Thus, its use may improve the accuracy in distinguishing these neoplasms from hepatocellular carcinoma. If ACC diagnosis is considered, acinar differentiation can be reliably demonstrated by trypsin/chymotrypsin.

Sensitivity and Specificity of Galectin-3 and Glypican-3 in Follicular-Patterned and Other Thyroid Neoplasms

INTRODUCTION

Diagnosing follicular-patterned thyroid neoplasm can be quiet challenging in some cases, where an immunohistochemical profiling becomes mandatory. Galectin-3 may be a helpful tool for classical PTC diagnosis, but it cannot be considered as a diagnostic marker of malignancy. Glypican-3, in contrast, is not thoroughly studied in thyroid neoplasms.

AIM

Determine the sensitivity and specificity of galectin-3 and glypican-3 in diagnosing thyroid carcinoma and follicular-patterned thyroid carcinoma.

MATERIALS AND METHODS

A retrospective study was conducted on archival blocks diagnosed from pathology department between 2010 and 2012 including 17 cases of follicular adenoma, 16 cases of Classic Papillary Thyroid Carcinoma (PTC), 6 cases of Follicular Variant of Papillary Thyroid Carcinoma (FVPTC), 3 cases of follicular carcinoma, 5 cases of medullary carcinoma and 1 case of Hürthle cell carcinoma. The nearby non neoplastic (normal) thyroid follicles present in both adenoma and carcinoma cases were also evaluated.

STUDY DESIGN

Evaluation of both galectin-3 and glypican-3 expression using standard immunohistochemical techniques.

STATISTICAL ANALYSIS USED

Descriptive analysis of the variables and statistical significances were calculated by non-parametric chi-square test using the Statistical Package for the Social Sciences version 12.0 (SPSS).

RESULTS

Five (30%) and 4 (24%) out of the 17 studied follicular adenoma cases, were positively stained by galectin-3 and glypican-3 respectively, while 30 (97%) and 25 (81%) cases out of the studied 31 carcinoma cases were positively stained by galectin-3 and glypican-3 respectively. The sensitivity, specificity and diagnostic accuracy of galectin-3 vs. glypican-3 in discrimination between thyroid carcinoma and adenoma was 96.8%, 70.6%, and 87.5%vs. 81% 76.5% and 79% respectively. As for the discrimination between follicular-patterned thyroid carcinoma and follicular adenoma it was 90%, 71% and 78% vs. 90% 76.5% and 82%.

CONCLUSION

Glypican-3 is more specific while galectin-3 is more sensitive in diagnosing thyroid carcinoma while glypican-3 is more specific than galectin-3 in discriminating follicular-patterned neoplasm.

Heterogeneity of liver cancer and personalized therapy

Liver cancer is an extraordinarily heterogeneous malignant disease among the tumors that have so far been identified. Hepatocellular carcinoma (HCC) arises most frequently in the setting of chronic liver inflammation and fibrosis, and takes a variety of course in individual patients to process to tumor. The risk factors such as HBV and/or HCV infections, aflatoxin infection, abuse alcohol intake, metabolic syndrome, obesity and diabetes are closely related to the environmental and genetic susceptibilities to HCC. The consequent resulting genomic instability, molecular and signal transduction network disorders and microenvironmental discrepancies are characterized by the extraordinary heterogeneity of liver cancer. The histology-based definition of the morphological heterogeneity of liver cancer has been modified and refined to treat patients with targeted therapies, but this still cannot solve all the problems. Lack of consistent outcome for anticancer agents and conventional therapies in liver cancer treatment calls for assessing the benefits of new molecularly targeted drugs and combined therapy, under the heterogeneity condition of tumor. The present review article will provide the complex mechanism and phenotype of liver cancer heterogeneity, and help us to execute precision medicine in a really personalized manner.

Differentially expressed gene profiles of intrahepatic cholangiocarcinoma, hepatocellular carcinoma, and combined hepatocellular-cholangiocarcinoma by integrated microarray analysis

Intrahepatic cholangiocarcinoma (ICC) and hepatocellular carcinoma (HCC) are common primary liver cancers worldwide. However, the survival and prognosis of ICC are much poorer than those of HCC, indicating the different molecular characteristics and mechanisms between ICC and HCC. To identify differentially expressed (DE) genes between ICC and HCC or combined hepatocellular-cholangiocarcinoma (CHC), we performed integrated analysis of publicly available microarray Gene Expression Omnibus (GEO) datasets by MetaOmics. Three GEO datasets comprising 32 ICC biochips, 77 HCC biochips, and 34 CHC biochips were available for the data integration. We identified 7313 DE genes between ICC and HCC, including 3650 upregulated genes and 3663 downregulated genes. The S100 family members on chromosome 1q21 were extensively upregulated in ICC, and S100A11 had the greatest degree of upregulation in ICC. Based on the DE genes, combined gene ontology and Kyoto Encyclopedia of Genes and Genomes analysis showed the enhanced pathways of local adhesion, ECM-receptor interaction, and regulation of action cytoskeleton, suggesting the enhanced communication between ICC and the microenvironment. Additionally, development-related genes and development-related pathways, including the Notch, Wnt, and TGF-β signaling pathways, were shown to be active prominently in ICC. Taken together, we identified the characteristically upregulated or downregulated DE genes and pathways in ICC compared with HCC or CHC. These DE genes and pathways supply new transcriptomics evidence for ICC and could help identify new therapeutic targets.

Diagnosis accuracy of serum glypican-3 in patients with hepatocellular carcinoma: a systematic review with meta-analysis

BACKGROUND AND AIMS

The diagnostic value of serum GPC3 in patients with hepatocellular carcinoma (HCC) remains controversial. Thus, we performed a systematic review and meta-analysis to assess the diagnostic accuracy of serum GPC3 for HCC.

METHODS

A systematic search was performed for the related studies. Sensitivity, specificity and other measures regarding the accuracy of serum GPC3 and alpha-fetoprotein (AFP) in the diagnosis of HCC were pooled using random-effects models. Summary receiver operating characteristic curve (sROC) analysis was used to summarize the overall test performance.

RESULTS

Nineteen studies were included in this meta-analysis. Pooled sensitivity, specificity and 95% confidence interval (CI) of serum GPC3 for the diagnosis of HCC were 55.2% (52.9-57.4%) and 84.2% (82.2-86.0%), respectively. When combining GPC3 with AFP, pooled sensitivity, specificity, and 95% CI were 75.7% (71.8-79.4%) and 83.3% (79.6-86.6%), respectively. The area under sROC (AUC) and 95% CI for AFP combined with GPC3 were 0.762 (0.649-0.875). For diagnosis of early HCC, pooled sensitivity and specificity of serum GPC3 were 55.1% (47.9-66.2%) and 97.0% (95.2-98.2%), respectively. The AUC of GPC3 for early HCC was 0.793 (0.668-0.917).

CONCLUSIONS

This meta-analysis indicates that serum GPC3 has a comparable accuracy to AFP for the diagnosis of HCC, and there is an elevation in the sensitivity of diagnosis when GPC3 was combined with AFP. Diagnostic accuracy of serum GPC3 for early HCC is still unsatisfactory.

Glypican-3 antibody functionalized Prussian blue nanoparticles for targeted MR imaging and photothermal therapy of hepatocellular carcinoma

MRI-guided photothermal therapy is becoming a more widely accepted minimally invasive technique.

Impaired autophagy response in human hepatocellular carcinoma

BACKGROUND

Autophagy is a cellular lysosomal degradation mechanism that has been implicated in chronic liver diseases and hepatocellular carcinoma (HCC). Association of autophagy defect with the development of human HCC has been shown in transgenic mouse model.

AIM

We performed this study to verify whether a defect in autophagy would play a role in human hepatocellular carcinoma (HCC).

METHODS

Archival tissue sections of 20 patients with HCC with or without hepatitis C virus (HCV) infection were studied. All slides were immunostained using monoclonal antibodies to p62 and glypican-3 with appropriate positive and negative controls. The expression of p62 and glycican-3 in the HCC and the surrounding non-tumor was semiquantitated. The cytoplasmic staining was graded as negative, weak or strong.

RESULTS

Positive p62 staining was found in 20 out of 20 (100%) HCCs and negative staining was observed in 20 out of 20 non-tumor areas and cirrhotic nodules. Positive glypican-3 staining was found in 70% of HCCs and negative staining was seen in all non-tumor areas. An autophagy defect leading to increased expression of p62 and glypican-3 was also seen in the HCC cell line (Huh-7.5), but not in the primary human hepatocytes. Activation of cellular autophagy in Huh-7.5 cells efficiently cleared p62 and glypican-3 expression and inhibition of autophagy induced the expression of p62 and glypican-3.

CONCLUSIONS

This study shows that p62 is increased in HCC compared to the surrounding non-tumorous liver tissue suggesting that human HCCs are autophagy defective. We provide further evidence that glypican-3 expression in HCC may also be related to defective autophagy. Our study indicates that p62 immunostain may represent a novel marker for HCC.

Immunohistochemistry for the novel markers glypican 3, PAX8, and p40 (ΔNp63) in squamous cell and urothelial carcinoma

OBJECTIVES

To examine squamous cell carcinomas (SCCs) from diverse anatomic sites and invasive urothelial carcinomas (UCs) for expression of the oncofetal antigen glypican 3 (GPC3), the paired box transcription factor PAX8, and the ΔN isoform of p63 (p40).

METHODS

Immunohistochemistry for GPC3, PAX8, and p40 was performed on whole sections of 107 SCCs from 11 anatomic sites and 49 UCs; evaluation included extent and intensity of staining.

RESULTS

GPC3 was detected in 20% of SCCs and 12% of UCs and PAX8 in 3% of SCCs, limited to the uterine cervix, and 10% of UCs. p40 Was found in 99% of SCCs and 96% of UCs.

CONCLUSIONS

GPC3 expression is frequent in SCC/UC, awareness of which should guard against an incorrect diagnosis of hepatocellular carcinoma, while PAX8, limited in distribution, may have some use in suggesting a cervical or urothelial tract origin in a metastatic squamotransitional carcinoma of unknown primary. There is no drop-off in sensitivity for the diagnoses of SCC or UC with ΔNp63-specific immunohistochemistry, and if this performance can be extended to other applications, p40 may supplant the dominant "pan-p63" antibody clone.

Reevaluation of glypican-3 as a serological marker for hepatocellular carcinoma

BACKGROUND

Glypican-3 (GPC3) is a novel histochemical marker of hepatocellular carcinoma (HCC). However, its utility as a serologic marker for HCC is not conclusive.

METHODS

A total of 1037 subjects, including 155 patients with HCC, 180 with chronic hepatitis, 124 with liver cirrhosis, 442 with non-HCC cancer and 136 healthy controls, were analyzed for serum GPC3 (sGPC3) by an ELISA constructed with 2 monoclonal antibodies.

RESULTS

The average level of sGPC3 in HCC patients was 99.94±267.2ng/ml, which was significantly higher than in patients with chronic hepatitis (10.45±46.02ng/ml, P<0.0001), liver cirrhosis (19.44±50.88ng/ml, P=0.0013), non-HCC cancer (20.50±98.33ng/ml, P<0.0001) and healthy controls (4.14±31.65ng/ml, P<0.0001). The sensitivity of sGPC3 in HCC diagnosis was 40.0%, whereas the specificity was 98.5%, 94.4% and 87.1% in healthy controls, chronic hepatitis patients and liver cirrhosis patients, respectively. In addition, 13.5% (28/207) of lung cancer patients and 13.2% (9/68) of thyroid cancer patients had positive results with sGPC3.

CONCLUSION

Serum GPC3 is a potential marker for HCC. However, the presence of sGPC3 in patients with lung cancer and thyroid cancer might limit its application as a single marker in the diagnosis of HCC.

Glypican-3 expression in gastrointestinal and pancreatic epithelial neoplasms

Glypican-3 (GPC3) is a plasma membrane-bound proteoglycan that can be overexpressed in certain malignancies but has been particularly linked to hepatocellular carcinoma (HCC). GPC3 is currently used as an immunohistochemical marker for HCC, but its expression in epithelial neoplasms of the gastrointestinal (GI) tract and pancreas, a common source of liver metastasis, has not been studied in detail. In this study, we examined GPC3 immunoreactivity in 98 neoplasms of the GI tract including 30 adenocarcinomas (ADCA), 29 squamous cell carcinomas (esophageal and anal), and 39 neuroendocrine carcinomas, and 60 neoplasms of the pancreas including 22 ADCA, 26 pancreatic neuroendocrine neoplasms, and 12 pancreatic acinar cell carcinomas. Two control groups of 32 HCCs and 16 intrahepatic cholangiocarcinomas were also stained with GPC3. Although most (7/12, 58.5%) acinar cell carcinomas were GPC3 positive, pancreatic ADCA and neuroendocrine neoplasms were GPC3 negative. In addition, 27.5%, (8/29) of squamous cell carcinomas, 20% (6/30) of ADCA, and 2.5% (1/39) of neuroendocrine carcinomas of the GI tract were immunoreactive for GPC3. HCC was positive for GPC3 in 75% (24/32) of cases but cholangiocarcinoma was negative. While significant correlation between GPC3 positivity and poor differentiation was observed in HCC only, GPC3 expression did not correlate with tumor size. In conclusion, 14% of GI tract and pancreatic carcinomas/neoplasms (particularly pancreatic acinar cell carcinoma) can express GPC3 by immunohistochemistry. As these tumors commonly metastasize to the liver, this offers a potential pitfall in differentiating between HCC and metastatic carcinoma when evaluating tumors involving the liver.

Evaluation of asymmetric immunoliposomal nanoparticles for cellular uptake

Effective and targeted in vivo delivery of polynucleotide therapeutics is the key for the treatment of many diseases. Asymmetric immunoliposomes can be used as vehicles to deliver polynucleotides effectively because the two leaflets of the bilayer can have different compositions, which enhance the delivery capacity. The formation and in vitro cellular uptake of asymmetric immunoliposomes containing polynucleotide cargoes were studied here. Maleimide-functionalised DSPE-PEG (2000) were incorporated into the outer leaflet to produce asymmetric liposomes capable of covalently attaching antibodies. Thiolated antibodies from both human and rabbit origin were conjugated to produce asymmetric pendant-type immunoliposomes that retain their specificity towards detection antibodies through the formation process. Human IgG-conjugated asymmetric immunoliposomes were readily internalised (>20 per cell) by macrophage, HEPG2, and CV-1 monkey kidney cells. The cells internalised the liposomal nanoparticles by the endocytic pathway. The immunoliposome-encapsulated endosomes were intact for at least 5 days and sequestered the plasmid from expression by the cell.

Preparation and in vitro studies of MRI-specific superparamagnetic iron oxide antiGPC3 probe for hepatocellular carcinoma

BACKGROUND

The aim of this study was to develop an antiGPC3-ultrasuperparamagnetic iron oxide (USPIO) probe for early detection of hepatocellular carcinoma.

METHODS

GPC3 and AFP receptors were selected as biomarkers and conjugated with USPIO nanoparticles coated by dextran with carboxylate groups to synthesize antiGPC3-USPIO and antiAFP-USPIO probes. HepG2 cells (a human hepatocellular carcinoma cell model with high expression of GPC3) were used along with SMMC-7721 cells (a hepatocellular carcinoma cell model with no expression of GPC3), HeLa cells (a cervical cancer model), and HL-7702 (normal hepatocytes) which were used as controls. After incubation with the probes, the iron content in the cells was calculated, USPIO nanoparticles in cells were observed using transmission electron microscopy, and T1 and T2 relaxation times were measured with a 1.5 T magnetic resonance scanner.

RESULTS

AntiGPC3-USPIO probes with a mean hydrodynamic diameter of 47 nm showed good biological compatibility. Transmission electron microscopic images indicated that the amount of USPIO nanoparticles taken up was significantly higher in HepG2 cells incubated with antiGPC3-USPIO than that in HepG2 cells incubated with antiAFP-USPIO or USPIO nanoparticles and that in the SMMC-7721 or HeLa cells incubated with antiGPC3-USPIO probes, antiAFP-USPIO probes, or USPIO nanoparticles. The higher the concentration and the longer the incubation time, the greater the number of USPIO nanoparticles found in the cells. No USPIO nanoparticles were found in the HL-7702 cells. All of the HepG2, SMMC-7721, and HeLa cells incubated with antiGPC3-USPIO, antiAFP-USPIO, or USPIO nanoparticles were able to shorten the T1 and T2 values in agar solution, especially the T2 images of HepG2 cells incubated with antiGPC3-USPIO probes.

CONCLUSION

AntiGPC3-USPIO probes can be utilized as a specific magnetic resonance targeting contrast agent for early detection of hepatocellular carcinoma. Using a 1.5 T magnetic resonance scanner, the optimal time for imaging HepG2 cells was around 2-4 hours after incubation with antiGPC3-USPIO probes.

Suppression of glypican 3 inhibits growth of hepatocellular carcinoma cells through up-regulation of TGF-β2

Glypican 3 (GPC3) is a valuable diagnostic marker and a potential therapeutic target in hepatocellular carcinoma (HCC). To evaluate the efficacy of targeting GPC3 at the translational level, we used RNA interference to examine the biologic and molecular effects of GPC3 suppression in HCC cells in vitro and in vivo. Transfection of Huh7 and HepG2 cells with GPC3-specific small interfering RNA (siRNA) inhibited cell proliferation (P < .001) together with cell cycle arrest at the G(1) phase, down-regulation of antiapoptotic protein (Bcl-2, Bcl-xL, and Mcl-1), and replicative senescence. Gene expression analysis revealed that GPC3 suppression significantly correlated with transforming growth factor beta receptor (TGFBR) pathway (P = 4.57e-5) and upregulated TGF-β2 at both RNA and protein levels. The effects of GPC3 suppression by siRNA can be recapitulated by addition of human recombinant TGF-β2 to HCC cells in culture, suggesting the possible involvement of TGF-β2 in growth inhibition of HCC cells. Cotransfection of siRNA-GPC3 with siRNA-TGF-β2 partially attenuated the effects of GPC3 suppression on cell proliferation, cell cycle progression, apoptosis, and replicative senescence, confirming the involvement of TGF-β2 in siRNA-GPC3-mediated growth suppression. In vivo, GPC3 suppression significantly inhibited the growth of orthotopic xenografts of Huh7 and HepG2 cells (P < .05), accompanied by increased TGF-β2 expression, reduced cell proliferation (observed by proliferating cell nuclear antigen staining), and enhanced apoptosis (by TUNEL staining). In conclusion, molecular targeting of GPC3 at the translational level offers an effective option for the clinical management of GPC3-positive HCC patients.

Glypican-3: a new target for cancer immunotherapy

Hepatocellular carcinoma (HCC) remains a common malignant cancer worldwide. There is an urgent need to identify new molecular targets for the development of novel therapeutic approaches. Herein, we review the structure, function and biology of glypican-3 (GPC3) and its role in human cancer with a focus on its potential as a therapeutic target for immunotherapy. GPC3 is a cell-surface protein that is over-expressed in HCC. Loss-of-function mutations of GPC3 cause Simpson-Golabi-Behmel syndrome (SGBS), a rare X-linked overgrowth condition. GPC3 binds Wnt and Hedgehog (Hh) signalling proteins. GPC3 is also able to bind basic growth factors such as fibroblast growth factor 2 through its heparan sulphate glycan chains. GPC3 is a promising candidate for liver cancer therapy given that it shows high expression in HCC. An anti-GPC3 monoclonal antibody has shown anti-cancer activity in mice and its humanised IgG molecule is currently undergoing clinical evaluation in patients with HCC. There is also evidence that soluble GPC3 may be a useful serum biomarker for HCC.

The use of immunohistochemistry in liver tumors

A variety of benign and malignant neoplasms can be encountered in the liver. Hematoxylin and eosin-stained tissue sections alone may not yield sufficient information to definitively diagnose liver tumors; therefore, ancillary studies with immunohistochemical markers can play a crucial role in differentiating the different hepatic neoplasms. The recent development of oncofetoprotein glypican-3 has added to the value of immunohistochemistry in diagnosing liver cancer. This review discusses the immunohistochemical markers used most often in the diagnosis of hepatic tumors.

Diagnostic role of serum glypican-3 in differentiating hepatocellular carcinoma from non-malignant chronic liver disease and other liver cancers

BACKGROUND AND AIMS

The role of glypican-3 (GPC3), a novel serum marker, in differentiating hepatocellular carcinoma (HCC) from non-malignant chronic liver disease and other malignant space-occupying lesions in the liver is largely unknown. The aims of this study were to evaluate its diagnostic role and clinical correlations in patients with HCC.

METHODS

Six groups were studied which included 40 healthy subjects, 50 patients with chronic hepatitis (CH), 50 patients with liver cirrhosis (LC), 100 patients with HCC, 50 patients with intrahepatic cholangiocarcinoma (ICC) and 50 patients with metastatic carcinoma (MCA). Serum GPC3 levels were measured by using a sandwich enzyme-linked immunosorbent assay method.

RESULTS

Fifty-three percent of HCC patients had elevated serum GPC3 levels with values ranging 35.5-7826.6 ng/mL. The serum marker was undetectable in other groups except one patient (2%) with LC and another patient (2%) with MCA. In most cases of HCC, elevated GPC3 values did not correlate with alpha-fetoprotein (AFP) levels. Detectable GPC3 was significantly correlated with the presence of viral hepatitis markers but was not correlated with tumor size and stage of HCC. Serum GPC3 was superior to AFP in detecting small HCC (56.3% and 31.3%, respectively). A combination of serum GPC3 and AFP yielded an improved sensitivity for detecting small HCC to 75%.

CONCLUSION

Serum GPC3 is highly specific for detecting HCC. The combined use of serum GPC3 and AFP provides a potentially promising tool to better differentiate HCC from benign liver disorders, as well as from other liver cancers.

Glypican-3 expression and its correlation with clinicopathological parameters in hepatocellular carcinoma

AIM: To investigate the expression of human glypican-3 (GPC-3) and analyze its correlation with clinicopathological parameters in hepatocellular carcinoma (HCC).

METHODS: Tumor specimens and matched tumor-adjacent and -distant specimens were taken from 36 HCC patients. The expression of GPC-3 in these specimens was detected by immunohistochemistry.

RESULTS: Positive GPC-3 signal was localized in both cell membrane and cytoplasm in HCC, and only in cytoplasm in tumor-adjacent tissue. No positive staining was found in tumor-distant tissue. The positive rate of GPC-3 expression was 80.6% in HCC and 41.7% in tumor-adjacent tissue. The intensity of GPC-3 expression was significantly higher in HCC than in tumor-adjacent and -distant tissues (χ² = 11.445, P < 0.01).

CONCLUSION: GPC-3 expression may be closely associated with the development and progression of HCC and can be used as a molecular marker for HCC diagnosis.

Molecular pathogenesis and early detection of hepatocellular carcinoma--perspectives from West Africa

This article reviews mechanisms involved in development of hepatocellular carcinoma and how host and environmental factors interact at a molecular level to cause cancer. These processes are intimately linked with strategies for early detection since molecular intermediates on the carcinogenesis pathway can now be detected with increasing levels of sensitivity. Similarly host factors influencing response to environmental agents, together with substances produced by early cancers, can be assayed in fine detail with new and emerging technologies. These advances in the field of biomarkers may lead to more rapid diagnosis and ultimately to improved survival as novel therapeutic strategies are adopted.

Glypican-3: a novel diagnostic marker for hepatocellular carcinoma and more

Glypican-3 (GPC3) is a heparan sulfate proteoglycan that plays an important role in cell growth and differentiation. GPC3 function is tissue dependent. In some tissues, GPC3 acts as a tumor suppressor gene, whereas in others, it acts as an oncofetal protein. Studies have shown that GPC3 is a reliable marker for hepatocellular carcinoma. The sensitivity and specificity exceeds both alpha-fetoprotein and hepatocyte-paraffin1. GPC3 immunohistochemistry can aid in the differentiation of testicular germ cell tumors, being expressed in all yolk sac tumors but not in seminomas. GPC3 expression has also been identified in some squamous cell carcinomas of the lung and clear cell carcinomas of the ovary. The role of GPC3 in melanomas is still controversial. This article reviews the current information on the application of GPC3 immunostaining in surgical pathology and cytology.

Gene expression profile analysis of human hepatocellular carcinoma using SAGE and LongSAGE

Background

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide and the second cancer killer in China. The initiation and malignant transformation of cancer result from accumulation of genetic changes in the sequences or expression level of cancer-related genes. It is of particular importance to determine gene expression profiles of cancers on a global scale. SAGE and LongSAGE have been developed for this purpose.

Methods

We performed SAGE in normal liver and HCC samples as well as the liver cancer cell line HepG2. Meanwhile, the same HCC sample was simultaneously analyzed using LongSAGE. Computational analysis was carried out to identify differentially expressed genes between normal liver and HCC which were further validated by real-time quantitative RT-PCR.

Results

Approximately 50,000 tags were sequenced for each of the four libraries. Analysis of the technical replicates of HCC indicated that excluding the low abundance tags, the reproducibility of SAGE data is high (R = 0.97). Compared with the gene expression profile of normal liver, 224 genes related to biosynthesis, cell proliferation, signal transduction, cellular metabolism and transport were identified to be differentially expressed in HCC. Overexpression of some transcripts selected from SAGE data was validated by real-time quantitative RT-PCR. Interestingly, sarcoglycan-ε (SGCE) and paternally expressed gene (PEG10) which is a pair of close neighboring genes on chromosome 7q21, showed similar enhanced expression patterns in HCC, implicating that a common mechanism of deregulation may be shared by these two genes.

Conclusion

Our study depicted the expression profile of HCC on a genome-wide scale without the restriction of annotation databases, and provided novel candidate genes that might be related to HCC.

Aggressive melanoma cells escape from BMP7-mediated autocrine growth inhibition through coordinated Noggin upregulation

Bone morphogenetic proteins (BMPs) are members of the TGF-beta superfamily responsible for mediating a diverse array of cellular functions both during embryogenesis and in adult life. Previously, we reported that upregulation of BMP7 in human melanoma correlates with tumor progression. However, melanoma cells are either inhibited by or become resistant to BMP7 as a function of tumor progression, with normal melanocytes being most susceptible. Herein, real-time quantitative reverse transcriptase-polymerase chain reactions and western blotting revealed that the expression of BMP antagonist, Noggin, correlates with resistance to BMP7 in advanced melanoma cells. To test the hypothesis that coordinated upregulation of Noggin protects advanced melanoma cells from autocrine inhibition by BMP7, functional expression of Noggin in susceptible melanoma cells was achieved by adenoviral gene transfer. The Noggin-overexpressing cells exhibited a growth advantage in response to subsequent BMP7 transduction in vitro under anchorage-dependent and -independent conditions, in three-dimensional skin reconstructs, as well as in vivo in severe combined immunodeficient mice. In concordance, Noggin knockdown by lentiviral shRNA confers sensitivity to BMP7-induced growth inhibition in advanced melanoma cells. Our findings suggest that, like TGF-beta, BMP7 acts as an autocrine growth inhibitor in melanocytic cells, and that advanced melanoma cells may escape from BMP7-induced inhibition through concomitant aberrant expression of Noggin.

Utility of glypican-3 in differentiating hepatocellular carcinoma from other primary and metastatic lesions in FNA of the liver: an immunocytochemical study

We evaluated the immunocytochemical expression of GPC3 in archival material obtained from fine needle aspiration of hepatic lesions to assess the sensitivity and specificity of this marker in cytological material and its potential diagnostic utility in differentiating hepatocellular carcinoma (HCC) from other primary benign or malignant hepatic tumors and from metastatic lesions in the liver. Forty-nine FNAs of the liver obtained between January 2000 and June 2006 were identified from our cytology files. Cytological diagnoses (confirmed by tissue diagnosis and/or clinical follow-up) included: 7 adenomas, 1 focal nodular hyperplasia (FNH), 24 HCCs, and 17 metastatic tumors. On the basis of the histological, clinical and/or radiological follow-up, 20 of 24 (83.3%) FNAs confirmed positive for HCC-expressed GPC3. All the seven adenomas and the only FNH were negative for GPC3. Sixteen out of seventeen metastatic malignancies were negative for GPC3. The only case expressing GPC3 was an anaplastic carcinoma with neuroendocrine features of unknown origin. In this study, the sensitivity of GPC3 in the diagnosis of HCC in the cytological material was 83.3%, the specificity 96%, the positive predictive value (PPV) 95% and negative predictive value (NPV) was 85.7%. Immunocytochemical staining for GPC3 in alcohol-fixed FNA material is a highly sensitive and specific method capable of distinguishing HCC from other benign and malignant hepatic lesions and from the great majority of metastatic lesions.

Glypican-3 immunocytochemistry in liver fine-needle aspirates : a novel stain to assist in the differentiation of benign and malignant liver lesions

BACKGROUND

Glypican-3 (GPC3) is a heparan sulfate proteoglycan which is elevated in the serum of patients with hepatocellular carcinoma (HCC), but not in healthy blood donors, or patients with benign liver disease. GPC3 immunohistochemistry (IHC) is a promising marker of HCC in surgical pathology. This study explores the value of GPC3 expression in liver fine-needle aspirates (FNAs) by immunocytochemistry (ICC), and compares its sensitivity and staining intensity with that of IHC.

METHODS

Archival cytologic material in hepatic FNAs from 20 patients with HCC, 20 patients with metastatic tumors, and 20 patients with benign lesions, were studied. Correlating surgical specimens and/or cell blocks were available for GPC-3 IHC in 16 patients with HCC. All slides were stained with GPC3-1G12 antibody with appropriate positive and negative controls. Staining intensity was graded as 0, no staining; 1, weak cytoplasmic staining; 2, moderate cytoplasmic staining; 3, strong cytoplasmic staining with membranous accentuation. Grades 0 and 1 were regarded as negative; grades 2 and 3 were considered positive for GPC3.

RESULTS

In the HCC group, positive staining was found in 18/20 (90%) samples. In contrast, GPC3 ICC of 20/20 (100%) metastatic tumors and 20/20 (100%) benign cases displayed negative staining, no cases showing moderate or strong expression. The sensitivity and specificity of GPC3 in HCC ICC were 90% and 100% respectively. The surgical sections and cell blocks of HCC demonstrated positive staining less frequently, in 11/16 (68.8%) cases, with 12/16 (75%) correlation with ICC.

CONCLUSIONS

Results indicated positive staining for GPC3 as defined in 90% of liver FNAs from HCC patients. All metastatic tumors and benign aspirates studied were negative for GPC3. ICC was superior to IHC in 25% of cases. This pilot study supports the diagnostic utility of GPC3 in hepatic FNAs to aid in distinction of HCC from metastatic tumors and benign liver lesions.

Glypican-3 expression in benign liver tissue with active hepatitis C: implications for the diagnosis of hepatocellular carcinoma

Glypican 3 is an oncofetal antigen that shows great promise as an adjunct to the diagnosis of hepatocellular carcinoma. To investigate whether glypican 3 might also appear in nonneoplastic liver cells, we performed immunostains on 60 biopsies of chronic hepatitis C, 30 with low-grade activity and 30 with high-grade activity. Glypican 3 immunoreactivity was detected in 25 (83.6%) of 30 in the high-grade but in none in the low-grade group. In 20% of the positive cases, glypican 3 produced strong cytoplasmic staining of more than 25% of hepatocytes and could potentially lead to a misdiagnosis of hepatocellular carcinoma. Pathologists should be aware of this phenomenon and exercise caution in interpreting biopsies or other specimens of suspected hepatocellular carcinoma when active necroinflammatory disease is present.

Expression of glypican 3 in hepatoblastoma: an immunohistochemical study of 65 cases

Glypican 3 is a heparin sulfate proteoglycan bound to the cell surface that is theorized to participate in cell signaling, resulting in embryonic cell growth and differentiation. The GPC3 gene is mutated in Simpson-Golabi-Behmel syndrome, whose features include numerous developmental abnormalities, tissue overgrowth, and an increased risk for embryonal malignancies, including hepatoblastoma. GPC3 has been detected in hepatic stem cells and was recently identified as one of the most overexpressed genes in hepatoblastoma by microarray analysis. The purpose of this study was to analyze the expression of GPC3 in a large series of hepatoblastoma using immunohistochemistry to assess its use as a diagnostic marker. The GPC3 immunoreactivity was semiquantitatively evaluated in 65 cases of hepatoblastoma. In addition, histologic patterns in each tumor were individually assessed for immunoreactivity. All 65 hepatoblastomas had cytoplasmic immunoreactivity for GPC3 with greater than 90% of cases showing strong, diffuse positivity. There was no reactivity in benign liver tissue. Fetal, embryonal, and small cell undifferentiated patterns were diffusely positive in almost all cases, whereas mesenchymal and teratoid patterns were nearly all negative. The high GPC3 expression consistently demonstrated in this study suggests that GPC3 may play a role in the tumorigenesis of hepatoblastoma.

Glypican-3 expression distinguishes small hepatocellular carcinomas from cirrhosis, dysplastic nodules, and focal nodular hyperplasia-like nodules

Distinguishing small hepatocellular carcinoma (HCC) from other types of small focal lesions that occur in a cirrhotic liver can be difficult on the basis of morphologic features alone. We investigated whether the expression of glypican-3 (GPC3) could be an ancillary tool in the histopathologic diagnostic process. We performed immunohistochemistry for GPC3 on 16 low-grade dysplastic nodules, 33 high-grade dysplastic nodules, 13 focal nodular hyperplasia-like nodules, and 59 HCCs with a diameter less or equal to 3 cm present in the cirrhotic liver of 66 patients. Both resected lesions and lesions biopsied by needle were included and nonlesional cirrhotic parenchyma was also stained. In a subset of cases (23 samples of cirrhosis, 4 low-grade dysplastic nodules, 5 high-grade dysplastic nodules, 2 focal nodular hyperplasia-like nodules, and 18 HCCs), real time reverse transcriptase-polymerase chain reaction for GPC3 was performed. GPC3 expression was, both on immunohistochemistry and by real time reverse transcriptase-polymerase chain reaction, much higher in small HCCs than in cirrhosis and other types of small focal lesions, indicating that the transition from premalignant lesions to small HCC is associated with a sharp increase of GPC3 expression in a majority of cases. The sensitivity and specificity of a positive GPC3-staining for the diagnosis of HCC in small focal lesions was 0.77 and 0.96, respectively, in resected cases, and 0.83 and 1, respectively, for needle biopsies. Because the result of the staining was easily interpretable, immunohistochemistry for GPC3 is valuable ancillary tool in the histopathologic diagnosis of small focal lesions in cirrhosis.

Comparison of membrane-associated proteins in human cholangiocarcinoma and hepatocellular carcinoma cell lines

Cholangiocarcinoma (CCA) and hepatocellular carcinoma (HCC) occur with relatively high incidence in Thailand. Cell line models, originating from Thai patients, are available for both diseases, including the human bile duct epithelial carcinoma cell line (HuCCA-1) and the HCC cell line HCC-S102. Here, we have prepared subproteomes enriched in membrane proteins or in cytosolic proteins from the HuCCA-1 and the HCC-S102 cell lines. Study of differential protein expression by 2-DE and LC/MS/MS showed 195 proteins expressed in the two cell lines, including both membrane-associated and cytosolic proteins. Eighteen proteins were found in both membrane and cytosolic fractions of HuCCA-1, but not in HCC-S102, while nine proteins were found in both membrane and cytosolic fractions of HCC-S102, but not in HuCCA-1. Ten membrane proteins were found in HuCCA-1 but not in HCC-S102, including integrin alpha-6 precursor, ezrin, hippocalcin-like protein 1, mitogen-activated protein kinase kinase kinase 2 (MAPK/ERK kinase kinase 2), and calgizzarin. Proteins showing increased expression in the membrane fraction of HuCCA-1 were mainly cytoskeletal proteins (40.9%), while proteins showing increased expression in the membrane fraction of HCC-S102 were mainly metabolic proteins (39.4%). The subproteomic approach used here facilitates detection of potential biomarkers undetected by regular proteomic methods.

New frontiers in biomarkers for hepatocellular carcinoma

Hepatocellular carcinoma represents the fifth most frequent cancer in the world; it commonly occurs on cirrhotic liver. Prognosis and survival are still poor, mainly because of diagnosis at a late stage and/or recurrence of the disease. For this reason, surveillance strategies are widely used to screen for early occurrence of cancer in populations at risk. Alpha-foetoprotein is so far the only serological marker available, but its diagnostic accuracy is unsatisfactory because of low sensitivity despite reliable specificity. For this reason, new biomarkers for the diagnosis of hepatocellular carcinoma are in strong demand by clinicians. In this review, we will focus on new biomarkers currently under investigation, but also on still newer, very promising biomarkers that seem to significantly improve diagnosis.