Hepatitis B and hepatitis C virus replication upregulates serine protease inhibitor Kazal, resulting in cellular resistance to serine protease-dependent apoptosis

Three-Dimensional Structure of Novel Liver Cancer Biomarker Liver Cancer-Specific Serine Protease Inhibitor Kazal (LC-SPIK) and Its Performance in Clinical Diagnosis of Hepatocellular Carcinoma (HCC)

LC-SPIK is a liver cancer-specific isoform of Serine Protease Inhibitor Kazal and has been proposed as a new biomarker for the detection of HCC given its unique 3D structure, which differs from normal pancreatic SPIK. An ELISA technology based on its unique structure was developed to use LC-SPIK as an effective biomarker for the clinical diagnosis of HCC. AFP, the most widely used biomarker for HCC surveillance currently, suffers from poor clinical performance, especially in the detection of early-stage HCC. In one case-control study, which included 164 HCC patients and 324 controls, LC-SPIK had an AUC of 0.87 compared to only 0.70 for AFP in distinguishing HCC from liver disease controls (cirrhosis, HBV/HCV). LC-SPIK also performed significantly better than AFP for the 81 patients with early-stage HCC (BCLC stage 0 and A), with an AUC of 0.85 compared to only 0.61 for AFP. Cirrhosis is the major risk factor for HCC; about 80% of patients with newly diagnosed HCC have preexisting cirrhosis. LC-SPIK's clinical performance was also studied in HCC patients with viral and non-viral cirrhosis, including cirrhosis caused by metabolic dysfunction-associated steatotic liver disease (MASLD) and alcoholic liver disease (ALD). In a total of 163 viral cirrhosis patients with 93 HCC patients (50 early-stage), LC-SPIK had an AUC of 0.85, while AFP had an AUC of 0.70. For patients with early-stage HCC, LC-SPIK had a similar AUC of 0.83, while AFP had an AUC of only 0.60. For 120 patients with nonviral cirrhosis, including 62 HCC (23 early-stage) patients, LC-SPIK had an AUC of 0.84, while AFP had an AUC of only 0.72. For the 23 patients with early-stage HCC, LC-SPIK had a similar AUC of 0.83, while the AUC for AFP decreased to 0.65. All these results suggest that LC-SPIK exhibits significantly better performance in the detection of HCC than AFP in all etiologies of liver diseases. In addition, LC-SPIK accurately detected the presence of HCC in 71-91% of HCC patients with false-negative AFP test results in viral-associated HCC and non-viral-associated HCC.

Serine protease inhibitor Kazal type 1 (SPINK1) promotes proliferation, migration, invasion and radiation resistance in rectal cancer patients receiving concurrent chemoradiotherapy: a potential target for precision medicine

Serine peptidase inhibitor Kazal type-1 (SPINK1), a trypsin kinase inhibitor, is known to be associated with inflammation and pathogenesis. The aim in this study was to demonstrate the clinicopathological role and progression of SPINK1 in rectal cancer (RC) patients undergoing concurrent chemoradiotherapy (CCRT). Immunohistochemical staining for SPINK1 protein expression in 111 RC cases revealed high SPINK1 expression was significantly associated with perineural invasion and poor CCRT response in pre-CCRT specimens. In addition, multivariable analyses showed that pre-CCRT SPINK1 expression was a significant prognostic marker of both overall and disease-free survival in RC patients receiving pre-operative CCRT; furthermore, in vitro studies demonstrated SPINK1 interacted with EGFR to promote the abilities of proliferation, migration and invasion attenuated by SPINK1 si-RNA via ERK, p38, and JNK pathways. SPINK1 was also found to regulate radio-resistance in CRC cell lines. In conclusion, SPINK1 expression is an independent prognostic marker in patients receiving pre-operative CCRT, and SPINK1 regulates proliferation, migration and invasion via EGFR-downstream ERK, p38 and JNK pathways. The phenotypes of radiosensitivity that could be reversed with attenuation of SPINK1 levels suggest that targeting SPINK1 might offer a strategy for optimal precision medicine.

SPINK2 is a prognostic biomarker related to immune infiltration in acute myeloid leukemia

BACKGROUND

Serine peptidase inhibitor Kazal type 2 (SPINK2) has been reported to be involved in certain cancers. We conducted an in-depth investigation on the role and mechanism of SPINK2 in acute myeloid leukemia (AML).

METHODS

The relationship between SPINK2 expression and AML clinicopathologic characteristics was determined using The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database. Concomitantly, we used Kaplan-Meier survival analysis, as well as univariate and multivariate regression analyses to evaluate SPINK2 as a prognostic marker of AML. Additionally, we annotated the enrichment and function of SPINK2 using Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Sets Enrichment Analysis (GSEA). The CIBERSORT algorithm was used to analyze the relationship between SPINK2 expression and immune infiltration.

RESULTS

SPINK2 expression was significantly higher in AML patients compared to healthy individuals (P<0.001). The area under receiver operating characteristic curve in the GSE9476 dataset was 0.660, whereas that in the Genotype-Tissue Expression (GTEx) and TCGA datasets was 0.935. In addition, GSEA also showed that several pathways were enriched in the group with high SPINK2 expression, such as PI3K-AKT signaling, PD-L1 expression, and checkpoint pathways. Analysis of immune infiltration showed that SPINK2 expression was correlated with certain immune infiltrating cells. Cox multivariate analysis revealed that the level of SPINK2 was an independent risk factor for the progression of AML (P<0.001). Moreover, age, M1, M5, M6, and CytoRisk-Poor also affected the progression of AML (P<0.05). The C-index of the nomogram in our internal validation was 0.702.

CONCLUSION

The high expression of SPINK2 in AML suggests that SPINK2 may play an important role in the immune microenvironment and thus could be a biomarker for diagnosis and prognosis of AML.

Alcohol Intake and Mortality in Patients With Chronic Viral Hepatitis: A Nationwide Cohort Study

INTRODUCTION

We evaluated the association between alcohol intake and all-cause and cause-specific mortality in subjects with chronic viral hepatitis, using nationwide population-based cohort study.

METHODS

A total of 364,361 men and women aged 40-84 years who underwent health screening examination between January 2002 and December 2013 that included assessment of frequency and amount of alcohol consumption were assessed for all-cause and cause-specific mortality.

RESULTS

In participants without chronic viral hepatitis, the fully adjusted hazard ratios (HRs) for all-cause mortality comparing light, moderate, and heavy drinkers with nondrinkers were 0.92 (95% confidence interval [CI] 0.87-0.98), 1.08 (95% CI 1.01-1.16), and 1.51 (95% CI 1.33-1.72), respectively. In participants with chronic viral hepatitis, the corresponding HRs were 1.19 (95% CI 1.05-1.36), 1.23 (95% CI 1.06-1.43), and 1.69 (95% CI 1.28-2.24), respectively (P value for alcohol intake by chronic viral hepatitis interaction <0.001). Compared with participants without chronic viral hepatitis, those with chronic viral hepatitis had substantially elevated liver cancer or liver disease (HR 10.85, 95% CI 9.74-12.09) and extrahepatic cancer mortality (HR 1.37, 95% CI 1.26-1.49). In patients with chronic viral hepatitis, the high mortality due to liver cancer or liver disease and the positive association of alcohol intake with liver cancer or liver disease mortality explained the positive association of alcohol intake with all-cause mortality.

DISCUSSION

Even light to moderate alcohol intake was associated with increased all-cause mortality in individuals with chronic viral hepatitis. Clinicians and public health campaigns should advise against any amount of alcohol intake in individuals with chronic viral hepatitis.

Targeting an autocrine IL-6-SPINK1 signaling axis to suppress metastatic spread in ovarian clear cell carcinoma

A major clinical challenge of ovarian cancer is the development of malignant ascites accompanied by widespread peritoneal metastasis. In ovarian clear cell carcinoma (OCCC), a challenging subtype of ovarian cancer, this problem is compounded by near-universal primary chemoresistance; patients with advanced stage OCCC thus lack effective therapies and face extremely poor survival rates. Here we show that tumor cell expressed serine protease inhibitor Kazal type 1 (SPINK1) is a key driver of OCCC progression and metastasis. Using cell culture models of human OCCC, we find that shRNA silencing of SPINK1 sensitizes tumor cells to anoikis and inhibits proliferation. Knockdown of SPINK1 in OCCC cells also profoundly suppresses peritoneal metastasis in mouse implantation models of human OCCC. We next identify a novel autocrine signaling axis in OCCC cells whereby tumor cell-produced interleukin-6 (IL-6) regulates SPINK1 expression to stimulate a common protumorigenic gene expression pattern leading to anoikis resistance and proliferation of OCCC cells. We further demonstrate that this signaling pathway can be successfully interrupted with the IL-6Rα inhibitor tocilizumab, sensitizing cells to anoikis in vitro and reducing metastasis in vivo. These results suggest that clinical trials of IL-6 pathway inhibitors in OCCC may be warranted, and that SPINK1 might offer a candidate predictive biomarker in this population.

Incidence of extrahepatic cancers among individuals with chronic hepatitis B or C virus infection: A nationwide cohort study

This study examined the association between chronic HBV or HCV infection and the risk of extrahepatic cancers. A total of 537 103 adults aged ≥20 years without history of cancer were identified from the Korean National Health Insurance Service-National Sample Cohort between 2003 and 2013. The difference in cancer incidence was compared between those with and without chronic HBV or HCV infection. During 3 854 130 person-years of follow-up (median follow-up: 8.0 years), 19 089 participants developed cancer. After adjusting for sex, body mass index, smoking, drinking, income percentile, residential area and comorbidities, hazard ratios (HRs) for incident extrahepatic cancer were significantly higher in participants with chronic HBV infection (HR: 1.27, 95% confidence interval [CI]: 1.20-1.35), HCV infection (HR: 1.31, 95% CI: 1.16-1.48) or HBV/HCV dual infection (HR: 1.41, 95% CI: 1.31-1.72) compared to participants without HBV or HCV infection. In chronic HBV infection, the cancer risk was higher for haematologic malignancy [HR (95% CI) = 2.46 (1.92-3.15)], gallbladder [1.55 (1.05-2.29)], pancreas [1.52 (1.07-2.15)], stomach [1.39 (1.22-1.58)], lung [1.27 (1.04-1.55)], colorectum [1.21 (1.03-1.42)] and thyroid cancer [1.20 (1.05-1.36)]. In chronic HCV infection, the cancer risk was higher for testis [10.34 (1.35-79.78)], gallbladder [2.90 (1.62-5.18)], prostate [2.51 (1.65-3.82)] and thyroid cancer [1.46 (1.10-1.93)]. In conclusion, chronic HBV or HCV infection was not only associated with an increased risk of liver cancer, but also associated with an increased risk of multiple extrahepatic cancers.

Hepatitis B Virus X Protein-Induced Serine Protease Inhibitor Kazal Type 1 Is Associated with the Progression of HBV-Related Diseases

Objective

Hepatitis B virus (HBV) causes inflammation of the liver and is the leading cause of both liver cirrhosis (LC) and hepatocellular carcinoma (HCC). Serine protease inhibitor Kazal type 1 (SPINK1) is an acute-phase response protein that is overexpressed in liver cancer tissue. This study investigated the clinical value of SPINK1 with regard to the diagnosis of HBV-related diseases and its regulatory mechanism.

Methods

Serum levels of SPINK1 in HBV-infected patients and healthy participants were detected by enzyme-linked immunosorbent assay (ELISA). Reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) and western blotting were used to detect differential expression of SPINK1 mRNA and protein in HepG2 and HepG2.2.15 cells. The HBV infectious clone pHBV1.3 and its individual genes were cotransfected into HepG2 cells with the SPINK1 promoter coupled to a luciferase reporter; luciferase activity was measured, and the expression levels of SPINK1 were examined.

Results

Serum SPINK1 levels of HBV-infected patients were significantly higher than those of healthy participants, and the serum levels of SPINK1 in patients who tested positive for HBeAg were significantly higher than those in patients who tested negative for HBeAg. The serum SPINK1 levels of patients with LC or HCC were markedly higher than those of patients with chronic hepatitis. The HBV X protein (HBx) activated the SPINK1 promoter to upregulate expression of SPINK1 at both mRNA and protein levels.

Conclusions

HBV enhances expression of SPINK1 through X. SPINK1 levels are increased during progression of HBV-related diseases and might be utilized as a biomarker for the diagnosis of HBV-related diseases.

Hepatitis C Virus and Nonliver Solid Cancers: Is There an Association between HCV and Cancers of the Pancreas, Thyroid, Kidney, Oral Cavity, Breast, Lung, and Gastrointestinal Tract?

Hepatitis C virus (HCV) is known for its oncogenic potential and has been found to be associated with hepatocellular carcinoma (HCC) and non-Hodgkin lymphoma. It has also been postulated that HCV may play a role in the development of other extrahepatic solid tumors of other organs of the body since it has been isolated from the vessel wall, kidney, and oral mucosa. In this article, we have reviewed epidemiological studies that have been done to look into the relationship of HCV with nonliver solid cancers of the pancreas, thyroid, renal, oral cavity, breast, and lung and nonpancreatic gastrointestinal cancers. Based on this review, HCV might be associated with an increased risk of renal cell and lung cancers.

Prognostic value of ERG, PTEN, CRISP3 and SPINK1 in predicting biochemical recurrence in prostate cancer

The established prognostic factors associated with prostatic adenocarcinoma are the Gleason score, pathological T staging and serum prostatic-specific antigen (PSA) level. However, these prognostic factors alone are not sufficient for predicting prognostic characteristics, including early stage or advanced prostate cancer, presence of metastasis or disease-related mortality. The purpose of the present study was to simultaneously evaluate the prognostic value and associations of four biomarkers, namely, transcriptional regulator ERG (ERG), phosphatase and tensin homolog (PTEN), cysteine-rich secretory protein 3 (CRISP3) and serine protease inhibitor Kazal type I (SPINK1), and to conduct risk stratification of prostate cancer for use in patient management. A total of 68 formalin-fixed, paraffin-embedded, prostate cancer samples from radical prostatectomies were obtained in the Kyung Hee University Hospital (Seoul, Korea) and were studied immunohistochemically for ERG, PTEN, CRISP3 and SPINK1 to determine the proportion and intensity of staining. SPINK1 expression was mutually exclusive of ERG expression (P=0.001). The loss of PTEN and high CRISP3 expression are unfavorable indicators for prostate cancer, as PTEN loss was associated with shorter biochemical recurrence (BCR) (P=0.039), and high CRISP3 expression was associated with increased BCR (P<0.001) and cancer-related mortalities (P=0.011). Using the combination of low PTEN and high CRISP3 expression enables attention to be focused on patients who exhibit a poor prognosis. Subgrouping of patients, into high-risk and low-risk categories, was correlated with BCR-free survival in prostate cancer upon multivariate analysis (P=0.030). Overall, low PTEN and high CRISP3 expression significantly characterize the subgroups of prostate cancer that have a poor prognosis for BCR.

Biomarker development, from bench to bedside

This review describes studies performed by our group and other laboratories in the field aimed at development of biomarkers not only for cancer but also for other diseases. The markers covered include tumor-associated trypsin inhibitor (TATI), tumor-associated trypsin (TAT), human chorionic gonadotropin (hCG), prostate-specific antigen (PSA) and their various molecular forms, their biology and diagnostic use. The discovery of TATI was the result of a hypothesis-driven project aimed at finding new biomarkers for ovarian cancer among urinary peptides. TATI has since proved to be a useful prognostic marker for several cancers. Recently, it has been named Serine Peptidase Inhibitor Kazal Type 1 (SPINK1) after being rediscovered by several groups as a tumor-associated peptide by gene expression profiling and proteomic techniques and shown to promote tumor development by stimulating the EGF receptor. To explain why a trypsin inhibitor is strongly expressed in some cancers, research focused on the protease that it inhibited led to the finding of tumor-associated trypsin (TAT). Elevated serum concentrations of TAT-2 were found in some cancer types, but fairly high background levels of pancreatic trypsinogen-2 limited the use of TAT-2 for cancer diagnostics. However, trypsinogen-2 and its complex with α1-protease inhibitor proved to be very sensitive and specific markers for pancreatitis. Studies on hCG were initiated by the need to develop more rapid and sensitive pregnancy tests. These studies showed that serum from men and non-pregnant women contains measurable concentrations of hCG derived from the pituitary. Subsequent development of assays for the subunits of hCG showed that the β subunit of hCG (hCGβ) is expressed at low concentrations by most cancers and that it is a strong prognostic marker. These studies led to the formation of a working group for standardization of hCG determinations and the development of new reference reagents for several molecular forms of hCG. The preparation of intact hCG has been adopted as the fifth international standard by WHO. Availability of several well-defined forms of hCG made it possible to characterize the epitopes of nearly 100 monoclonal antibodies. This will facilitate design of immunoassays with pre-defined specificity. Finally, the discovery of different forms of immunoreactive PSA in serum from a prostate cancer patient led to identification of the complex between PSA and α1-antichymotrypsin, and the use of assays for free and total PSA in serum for improved diagnosis of prostate cancer. Epitope mapping of PSA antibodies and establishment of PSA standards has facilitated establishment well-standardized assays for the various forms of PSA.

IL-17A G197A gene polymorphism contributes to susceptibility for liver cirrhosis development from patients with chronic hepatitis B infection in Chinese population

BACKGROUND

IL-17A G197A and IL-17F A7488G gene polymorphisms are found to be associated with the risk of several diseases, however few studies have focused on their correlation with risk of liver cirrhosis (LC).

AIMS

The aim of this study was to assess the impact of IL-17A G197A and IL-17F A7488G gene polymorphisms on development of LC from chronic hepatitis B (CHB) in Chinese patients.

METHODS

A total of 163 HBV-related LC patients and 168 CHB patients were enrolled in the present study. IL-17A and IL-17F gene polymorphisms were analyzed using a polymerase chain reaction (PCR) restriction fragment length polymorphism assay (PCR-RFLP).

RESULTS

Frequencies of IL-17A G197A genotype AA and allele A were significantly higher in LC patients compared with that in CHB patients (AA 42.33% vs 27.98%, P = 0.032; A 56.34% vs 46.15%, P=0.011, respectively); While no significant difference in frequencies of genotypes and alleles of IL-17F A7488G was found between the two groups. The AA genotype of IL-17A G197A significantly increased LC risk (OR 4.186, 95% CI: 1.479-11.844), while A allele carriers were also associated with an increased LC risk (OR 1.856, 95% CI: 1.161-2.967).

CONCLUSION

IL-17A G197A is a candidate gene that confers the genetic susceptibility for LC development from CHB in Chinese population.

SPINK1 expression is tightly linked to 6q15- and 5q21-deleted ERG-fusion negative prostate cancers but unrelated to PSA recurrence

BACKGROUND

The serine peptidase inhibitor, Kazal type 1 (SPINK1) has been suggested to define an aggressive molecular subtype of ERG-fusion negative prostate cancer. It was the aim of this study to further study the clinical relevance of SPINK1 expression and its relationship with other key genomic alterations of prostate cancer.

METHODS

A tissue microarray containing more than 10,000 prostate cancers with clinical follow-up was used for immunohistochemical SPINK1 analysis. Data on ERG status as well as PTEN, 6q, 5q, and 3p deletions were available for comparison.

RESULTS

SPINK1 expression was absent in benign prostate glands and detectable in 5.9% of 9,503 interpretable prostate cancers. Presence of SPINK1 expression was markedly more frequent in ERG negative (10.4%) than in ERG positive cancers (0.3%; P < 0.0001). However, SPINK1 expression was unrelated to tumor phenotype and biochemical recurrence in all cancers and in the subgroup of ERG negative cancers. Further subgroup analyses revealed, however, that--within ERG negative cancers--SPINK1 expression was significantly linked to deletions at 6q15 (P < 0.0001) and 5q21 (P = 0.0042).

CONCLUSIONS

Our results exclude SPINK1 as a relevant prognostic prostate cancer biomarker. However, the data demonstrate that SPINK1 overexpression is tightly linked to the small subsets of 6q15- and 5q21-deleted ERG negative prostate cancers. These findings support the concept of molecularly defined subtypes of prostate cancers.

Prognostic significance of tumor-associated trypsin inhibitor (TATI) and human chorionic gonadotropin-β (hCGβ) in patients with hepatocellular carcinoma

AIM

Hepatocellular carcinoma (HCC) is the sixth most common cancer and the third most frequent cause of cancer death worldwide. The aim of this study was to evaluate the prognostic value of serum tumor-associated trypsin inhibitor (TATI) and the free β subunit of human chorionic gonadotropin (hCGβ) in patients with HCC.

METHODS

The serum concentrations of TATI and hCGβ were determined by time-resolved immunofluorometric assays (IFMA) in pretreatment serum samples from 144 patients with HCC. Clinical data were retrieved from patient records and survival data obtained from Statistics Finland.

RESULTS

The overall cumulative disease-specific survival was 69% at 1 year, 50% at 2 years and 33% at 5 years. Disease-specific median survival time was 26 months. The overall survival in patients with low serum concentrations of TATI or hCGβ was statistically significantly better than in patients with elevated concentrations (p = 0.003 and 0.003, respectively). In multivariate analysis, both serum TATI and serum hCGβ were independent prognostic markers.

CONCLUSION

The results imply that elevated serum concentrations of TATI and hCGβ are predictors of adverse prognosis in patients with HCC and appear to be useful adjuncts in predicting prognosis in patients with HCC.

Screening and identification of compounds with antiviral activity against hepatitis B virus using a safe compound library and novel real-time immune-absorbance PCR-based high throughput system

There are now seven nucleoside/tide analogues, along with interferon-α, that are approved by the FDA for the management of chronic hepatitis B virus (HBV) infection, a disease affecting hundreds of millions of people worldwide. These medications, however, are limited in usefulness, and significant side effects and the emergence of viral escape mutants make the development of novel and updated therapeutics a pressing need in the treatment of HBV. With this in mind, a library containing 2000 compounds already known to be safe in both humans and mice with known mechanisms of action in mammalian cells were tested for the possibility of either antiviral activity against HBV or selective toxicity in HBV producing cell lines. A modified real-time immune-absorbance-polymerase chain reaction (IA-PCR) assay was developed for this screen, utilizing cells that produce and secrete intact HBV virions. In this procedure, viral particles are first captured by an anti-HBs antibody immobilized on a plate. The viral load is subsequently assessed by real-time PCR directly on captured particles. Using this assay, eight compounds were shown to consistently reduce the amount of secreted HBV viral particles in the culture medium under conditions that had no detectable impact on cell viability. Two compounds, proparacaine and chlorophyllide, were shown to reduce HBV levels 4- to 6-fold with an IC₅₀ of 1 and 1.5 μM, respectively, and were selected for further study. The identification of these compounds as promising antiviral drug candidates against HBV, despite a lack of previous recognition of HBV antiviral activity, supports the validity and utility of testing known compounds for "off-pathogen target" activity against HBV, and also validates this IA-PCR assay as an important tool for the detection of anti-viral activity against enveloped viruses.

Global gene expression profiling reveals SPINK1 as a potential hepatocellular carcinoma marker

BACKGROUND

Liver cirrhosis is the most important risk factor for hepatocellular carcinoma (HCC) but the role of liver disease aetiology in cancer development remains under-explored. We investigated global gene expression profiles from HCC arising in different liver diseases to test whether HCC development is driven by expression of common or different genes, which could provide new diagnostic markers or therapeutic targets.

METHODOLOGY AND PRINCIPAL FINDINGS

Global gene expression profiling was performed for 4 normal (control) livers as well as 8 background liver and 7 HCC from 3 patients with hereditary haemochromatosis (HH) undergoing surgery. In order to investigate different disease phenotypes causing HCC, the data were compared with public microarray repositories for gene expression in normal liver, hepatitis C virus (HCV) cirrhosis, HCV-related HCC (HCV-HCC), hepatitis B virus (HBV) cirrhosis and HBV-related HCC (HBV-HCC). Principal component analysis and differential gene expression analysis were carried out using R Bioconductor. Liver disease-specific and shared gene lists were created and genes identified as highly expressed in hereditary haemochromatosis HCC (HH-HCC) were validated using quantitative RT-PCR. Selected genes were investigated further using immunohistochemistry in 86 HCC arising in liver disorders with varied aetiology. Using a 2-fold cut-off, 9 genes were highly expressed in all HCC, 11 in HH-HCC, 270 in HBV-HCC and 9 in HCV-HCC. Six genes identified by microarray as highly expressed in HH-HCC were confirmed by RT qPCR. Serine peptidase inhibitor, Kazal type 1 (SPINK1) mRNA was very highly expressed in HH-HCC (median fold change 2291, p = 0.0072) and was detected by immunohistochemistry in 91% of HH-HCC, 0% of HH-related cirrhotic or dysplastic nodules and 79% of mixed-aetiology HCC.

CONCLUSION

HCC, arising from diverse backgrounds, uniformly over-express a small set of genes. SPINK1, a secretory trypsin inhibitor, demonstrated potential as a diagnostic HCC marker and should be evaluated in future studies.

Hepatitis B- and hepatitis C-related hepatocellular carcinomas in the United States: similarities and differences

CONTEXT

Hepatitis B and Hepatitis C (HBV and HCV) infections are both major causes of hepatocellular carcinoma (HCC). However, HCC caused by each of these two viruses has unique characteristics that should be studied independently to that of another one. While HBV- and HCV-related HCCs share similar host and environmental risk factors such as male gender, age above 50 years old, family history of HCC, cirrhosis, obesity, and concomitant alcohol/tobacco use, they differ in their viral risk factors.

EVIDENCE ACQUISITION

The actual level of HBV DNA, the presence of HBV e antigen (HBeAg), and mutations in the viral genome are important predisposing factors to HCC development in HBV, whereas in HCV, viremia of any amount denotes an elevated risk. HBV and HCV also differ in their mechanisms of carcinogenesis. For example, HBV can integrate into the host genome and induce many different genetic alterations/mutations. Ultimately, though, both viruses act on similar pathways to produce HCC.

RESULT

HBV and HCV are often transmitted differently - vertically (HBV) and horizontally (HCV), which may play a role in their distinct clinical presentations: HBV patients are younger and more frequently have larger/ bilobar tumors as opposed to HCV patients, who have worse liver function on diagnosis of HCC. Even the way they respond to treatment seems to be different. HBV-related HCC patients tend to progress faster after sorafenib treatments.

CONCLUSIONS

Future studies should investigate the ways in which these differences between HBV- and HCV-related HCC can translate into more tailored treatment strategies for each etiology of HCC in order to improve outcomes of both.

Molecular mechanisms of ursodeoxycholic acid toxicity & side effects: ursodeoxycholic acid freezes regeneration & induces hibernation mode

Ursodeoxycholic acid (UDCA) is a steroid bile acid approved for primary biliary cirrhosis (PBC). UDCA is reported to have “hepato-protective properties”. Yet, UDCA has “unanticipated” toxicity, pronounced by more than double number of deaths, and eligibility for liver transplantation compared to the control group in 28 mg/kg/day in primary sclerosing cholangitis, necessitating trial halt in North America. UDCA is associated with increase in hepatocellular carcinoma in PBC especially when it fails to achieve biochemical response (10 and 15 years incidence of 9% and 20% respectively). “Unanticipated” UDCA toxicity includes hepatitis, pruritus, cholangitis, ascites, vanishing bile duct syndrome, liver cell failure, death, severe watery diarrhea, pneumonia, dysuria, immune-suppression, mutagenic effects and withdrawal syndrome upon sudden halt. UDCA inhibits DNA repair, co-enzyme A, cyclic AMP, p53, phagocytosis, and inhibits induction of nitric oxide synthatase. It is genotoxic, exerts aneugenic activity, and arrests apoptosis even after cellular phosphatidylserine externalization. UDCA toxicity is related to its interference with drug detoxification, being hydrophilic and anti-apoptotic, has a long half-life, has transcriptional mutational abilities, down-regulates cellular functions, has a very narrow difference between the recommended (13 mg/kg/day) and toxic dose (28 mg/kg/day), and it typically transforms into lithocholic acid that induces DNA strand breakage, it is uniquely co-mutagenic, and promotes cell transformation. UDCA beyond PBC is unjustified.

Validation and comparison of tumor-associated trypsin inhibitor (TATI) immunoassays

BACKGROUND

Tumor-associated trypsin inhibitor (TATI) is mainly proposed as a tumor marker for ovarian cancer. However, recent discoveries of TATI in cancer and inflammatory diseases show that assay of TATI in biological samples is of increasing interest.

METHODS

We validated a previously described TR-IFMA and a newly developed dual-monoclonal sandwich ELISA for TATI. These methods were compared with a commercial radioimmunoassay (RIA). We studied preanalytical factors affecting serum TATI concentrations and established age- and gender specific reference intervals using serum samples from 195 healthy volunteers.

RESULTS

The assay range and precision were 0.8-45 μg/L and <9.1% for the ELISA, and 0.13 μg/L-150 μg/L and <12.5% for the TR-IFMA, respectively. Both assays correlated well with a RIA. Type of blood sample and nutritional status were not critical and TATI was stable in serum samples when stored at +4°C and -20°C for 4 weeks and at -80°C for 8 weeks. The 95% reference limits for serum TATI in adults were 5.2-15.3 μg/L in the age group 18-70 years and 7.5-21.3 μg/L in the age group >70 years.

CONCLUSIONS

Significantly higher concentrations of serum TATI were observed in elderly women and in men. Both ELISA and TR-IFMA technologies can be employed to develop sensitive and robust immunoassays for TATI using monoclonal antibodies.

Role of the inflammatory protein serine protease inhibitor Kazal in preventing cytolytic granule granzyme A-mediated apoptosis

Serine protease inhibitor Kazal (SPIK) is an inflammatory protein whose levels are elevated in numerous cancers. However, the role of this protein in cancer development is unknown. We have recently found that SPIK suppresses serine protease-dependent cell apoptosis. Here, we report that anti-SPIK antibodies can co-immmunoprecipitate serine protease granzyme A (GzmA), a cytolytic granule secreted by cytotoxic T lymphocytes and natural killer cells during immune surveillance, and that SPIK suppresses GzmA-induced cell apoptosis. Deletion studies show that the C3-C4 region of SPIK is critical for this suppression. These studies suggest that over-expression of SPIK may prevent GzmA-mediated immune-killing, thereby establishing the tolerance of cancer cells to the body's immune surveillance system. Suppression of over-expressed SPIK can restore the susceptibility of these cells to apoptotic death triggered by GzmA. This finding implies that it is possible to overcome tolerance of cancer cells to the body's immune surveillance system and restore the GzmA-mediated immune-killing by suppressing the over-expression of SPIK.

Impaired spermatogenesis and fertility in mice carrying a mutation in the Spink2 gene expressed predominantly in testes

Spermatogenesis is a complex process involving an intrinsic genetic program composed of germ cell-specific and -predominant genes. In this study, we investigated the mouse Spink2 (serine protease inhibitor Kazal-type 2) gene, which belongs to the SPINK family of proteins characterized by the presence of a Kazal-type serine protease inhibitor-pancreatic secretory trypsin inhibitor domain. We showed that recombinant mouse SPINK2 has trypsin-inhibitory activity. Distribution analyses revealed that Spink2 is transcribed strongly in the testis and weakly in the epididymis, but is not detected in other mouse tissues. Expression of Spink2 is specific to germ cells in the testis and is first evident at the pachytene spermatocyte stage. Immunoblot analyses demonstrated that SPINK2 protein is present in male germ cells at all developmental stages, including in testicular spermatogenic cells, testicular sperm, and mature sperm. To elucidate the functional role of SPINK2 in vivo, we generated mutant mice with diminished levels of SPINK2 using a gene trap mutagenesis approach. Mutant male mice exhibit significantly impaired fertility; further phenotypic analyses revealed that testicular integrity is disrupted, resulting in a reduction in sperm number. Moreover, we found that testes from mutant mice exhibit abnormal spermatogenesis and germ cell apoptosis accompanied by elevated serine protease activity. Our studies thus provide the first demonstration that SPINK2 is required for maintaining normal spermatogenesis and potentially regulates serine protease-mediated apoptosis in male germ cells.

Combined genomic and phenotype screening reveals secretory factor SPINK1 as an invasion and survival factor associated with patient prognosis in breast cancer

Secretory factors that drive cancer progression are attractive immunotherapeutic targets. We used a whole-genome data-mining approach on multiple cohorts of breast tumours annotated for clinical outcomes to discover such factors. We identified Serine protease inhibitor Kazal-type 1 (SPINK1) to be associated with poor survival in estrogen receptor-positive (ER+) cases. Immunohistochemistry showed that SPINK1 was absent in normal breast, present in early and advanced tumours, and its expression correlated with poor survival in ER+ tumours. In ER− cases, the prognostic effect did not reach statistical significance. Forced expression and/or exposure to recombinant SPINK1 induced invasiveness without affecting cell proliferation. However, down-regulation of SPINK1 resulted in cell death. Further, SPINK1 overexpressing cells were resistant to drug-induced apoptosis due to reduced caspase-3 levels and high expression of Bcl2 and phospho-Bcl2 proteins. Intriguingly, these anti-apoptotic effects of SPINK1 were abrogated by mutations of its protease inhibition domain. Thus, SPINK1 affects multiple aggressive properties in breast cancer: survival, invasiveness and chemoresistance. Because SPINK1 effects are abrogated by neutralizing antibodies, we suggest that SPINK1 is a viable potential therapeutic target in breast cancer.

The role of oncogenic viruses in the pathogenesis of hepatocellular carcinoma

HBV and HCV have major roles in hepatocarcinogenesis. More than 500 million people are infected with hepatitis viruses and, therefore, HCC is highly prevalent, especially in those countries endemic for HBV and HCV. Viral and host factors contribute to the development of HCC. The main viral factors include the circulating load of HBV DNA or HCV RNA and specific genotypes. Various mechanisms are involved in the host-viral interactions that lead to HCC development, among which are genetic instability, self-sufficiency in growth signals, insensitivity to antigrowth signals, evasion of apoptosis, limitless replicative potential, sustained angiogenesis, and tissue invasiveness. Prevention of HBV by vaccination, as well as antiviral therapy against HBV and for HCV seem able to inhibit the development of HCC.

Frequency of HCV infection in renal cell carcinoma patients

Chronic infections with hepatitis C virus (HCV) are frequently pronounced in the etiology of malignancies especially in hepatocellular carcinoma. The association between HCV and risk of renal cell carcinoma (RCC) development has been stated recently. The authors retrospectively evaluated hepatitis serology for HCV and HBV in patients who had RCC diagnosis between 2005 and 2010 in six oncology centers. Control group was also included from the three different published studies that hepatitis serology studied in healthy people that has been living in the same geographic regions. Histologically confirmed 903 RCC cases and 5,267 healthy subjects were included the study. Median age at diagnosis of RCC was 58 (range: 26-89). There was no increase in HCV positivity in RCC patients compared to healthy control group (1.7 vs. 1.5%; P = 0.77). Frequency of HBsAg positivity was 4.4 and 4.1% in RCC and control groups, respectively (P = 0.65). There is no increase in frequency of HCV and HBsAg positivity in RCC patients. HCV positivity in RCC patients were not different from the healthy people.

Tumor viruses and cancer biology: Modulating signaling pathways for therapeutic intervention

Tumor viruses have provided relatively simple genetic systems, which can be manipulated for understanding the molecular mechanisms of the cellular transformation process. A growing body of information in the tumor virology field provides several prospects for rationally targeted therapies. However, further research is needed to better understand the multiple mechanisms utilized by these viruses in cancer progression in order to develop therapeutic strategies. Initially viruses were believed to be associated with cancers as causative agents only in animals. It was almost half a century before the first human tumor virus, Epstein-Barr virus (EBV), was identified in 1964. Subsequently, several human tumor viruses have been identified including Kaposi sarcoma associated herpesvirus (KSHV), human Papillomaviruses (HPV), Hepatitis B virus (HBV), Hepatitis C virus (HCV), Human T lymphotropic virus (HTLV-1) and recently identified Merkel cell Polyomavirus (MCPyV). Tumor viruses are sub-categorized as either DNA viruses, which include EBV, KSHV, HPV, HBV, and MCPyV, or RNA viruses such as HCV and HTLV-1. Tumor-viruses induce oncogenesis through manipulating an array of different cellular pathways. These viruses initiate a series of cellular events, which lead to immortalization and proliferation of the infected cells by disrupting the mitotic checkpoint upon infection of the host cell. This is often accomplished by functional inhibition or proteasomal degradation of many tumor suppressor proteins by virally encoded gene products. The virally infected cells can either be eliminated via cell-mediated apoptosis or persist in a state of chronic infection. Importantly, the chronic persistence of infection by tumor viruses can lead to oncogenesis. This review discusses the major human tumor associated viruses and their ability to modulate numerous cell signaling pathways, which can be targeted for potential therapeutic approaches.