Increased serum levels of tumour-associated trypsin inhibitor independently predict a poor prognosis in colorectal cancer patients

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.

Tumor-Associated Trypsin Inhibitor (TATI) as a Biomarker of Poor Prognosis in Oropharyngeal Squamous Cell Carcinoma Irrespective of HPV Status

BACKGROUND

We studied the role of tumor-associated trypsin inhibitor (TATI) in serum and in tumor tissues among human papillomavirus (HPV)-positive and HPV-negative OPSCC patients.

MATERIALS AND METHODS

The study cohort included 90 OPSCC patients treated at the Helsinki University Hospital (HUS), Helsinki, Finland, in 2012-2016. TATI serum concentrations (S-TATIs) were determined by an immunofluorometric assay. Immunostaining was used to assess tissue expression. HPV status was determined with a combination of p16 immunohistochemistry and HPV DNA PCR genotyping. The survival endpoints were overall survival (OS) and disease-specific survival (DSS).

RESULTS

A significant correlation was found between S-TATI positivity and poor OS (p < 0.001) and DSS (p = 0.04) in all patients. In HPV-negative cases, S-TATI positivity was linked to poor OS (p = 0.01) and DSS (p = 0.05). In HPV-positive disease, S-TATI positivity correlated with poor DSS (p = 0.01). S-TATI positivity was strongly associated with HPV negativity. TATI serum was negatively linked to a lower cancer stage. TATI expression in peritumoral lymphocytes was associated with favorable OS (p < 0.025) and HPV positivity. TATI expression in tumor and in peritumoral lymphocytes correlated with lower cancer stages.

CONCLUSION

Our results suggest that S-TATI positivity may be a biomarker of poor prognosis in both HPV-positive and HPV-negative OPSCC.

Transcriptome profiling reveals an integrated mRNA-lncRNA signature with predictive value of early relapse in colon cancer

The purpose of our study was to develop a multigene signature based on transcriptome profiles of both mRNAs and lncRNAs to identify a group of patients who are at high risk of early relapse in stages II-III colon cancer. Firstly, propensity score matching was conducted between patients in early relapse group and long-term survival group from GSE39582 training series (N = 359) and patients were matched 1:1. Global transcriptome analysis was then performed between the paired groups to identify tumor specific mRNAs and lncRNAs. Finally, using LASSO Cox regression model, we built a multigene early relapse classifier incorporating 15 mRNAs and three lncRNAs. The prognostic and predictive accuracy of the signature was internally validated in 102 colon cancer patients and externally validated in other 241 patients. In the training set, patients with high risk score were more likely to suffer from relapse than those with low risk score (HR: 2.67, 95% CI: 2.07-3.46, P < 0.001). The results were validated in the internal validation set (HR: 2.23, 95% CI: 1.23-3.78, P = 0.003) and external validation (HR 1.88, 95% CI 1.42-2.48; P < 0.001) set. Time-dependent receiver operating curve at 1 year showed that the integrated mRNA-lncRNA signature [area under curve (AUC) = 0.742] had better prognostic accuracy than AJCC TNM stage (AUC = 0.615) in the entire 702 patients. In addition, survival decision curve analyses at 12 months revealed a good clinical usefulness of the integrated mRNA-lncRNA signature. In conclusion, we successfully developed an integrated mRNA-lncRNA signature that can accurately predict early relapse.

Plasma Protein Profiling Reveal Osteoprotegerin as a Marker of Prognostic Impact for Colorectal Cancer

BACKGROUND: Due to difficulties in predicting recurrences in colorectal cancer stages II and III, reliable prognostic biomarkers could be a breakthrough for individualized treatment and follow-up. OBJECTIVE: To find potential prognostic protein biomarkers in colorectal cancer, using the proximity extension assays. METHODS: A panel of 92 oncology-related proteins was analyzed with proximity extension assays, in plasma from a cohort of 261 colorectal cancer patients with stage II-IV. The survival analyses were corrected for disease stage and age, and the recurrence analyses were corrected for disease stage. The significance threshold was adjusted for multiple comparisons. RESULTS: The plasma proteins expression levels had a greater prognostic relevance in disease stage III colorectal cancer than in disease stage II, and for overall survival than for time to recurrence. Osteoprotegerin was the only biomarker candidate in the protein panel that had a statistical significant association with overall survival (P = .00029). None of the proteins were statistically significantly associated with time to recurrence. CONCLUSIONS: Of the 92 analyzed plasma proteins, osteoprotegerin showed the strongest prognostic impact in patients with colorectal cancer, and therefore osteoprotegerin is a potential predictive marker, and it also could be a target for treatments.

Postoperative CEA is a better prognostic marker than CA19-9, hCGβ or TATI after resection of colorectal liver metastases

Liver metastases of colorectal cancer can be operated with a curative intent in selected cases. However, more than half of the patients have a recurrence. The aim of this study was to evaluate the prognostic and predictive value of carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), human chorionic gonadotropin β (hCGβ) and tumour-associated trypsin-inhibitor (TATI) in colorectal cancer patients before and 3 months after resection of liver metastases. Marker concentrations were determined in blood samples from 168 colorectal cancer patients, who underwent liver resection between the years 1998 and 2007 at Helsinki University Hospital, Finland. The samples were taken before and 3 months after curative resection. Increased concentrations of CEA (>5 µg/L) and hCGβ (>1 pmol/L) 3 months after liver resection correlated with recurrence and impaired overall survival and increased CA19-9 (>26 kU/L) with impaired overall survival, but postoperative TATI was not prognostic. Preoperatively elevated CEA and CA19-9 correlated with impaired overall survival, but not with recurrence. Neither preoperative hCGβ nor TATI was prognostic. In conclusion, CEA is a useful prognostic marker, when measured 3 months after resection of colorectal liver metastases. CA19-9 also has prognostic significance and may have additional value.

MAPK inhibitors induce serine peptidase inhibitor Kazal type 1 (SPINK1) secretion in BRAF V600E-mutant colorectal adenocarcinoma

The mitogen-activated protein kinase (MAPK) pathway plays a central role in colorectal cancers (CRC). In particular, BRAF V600E-mutant tumors, which represent around 10% of CRCs, are refractory to current therapies. Overexpression and secretion of serine peptidase inhibitor Kazal type 1 (SPINK1) are observed in around 50% of CRCs, and its serum level can be used as a biomarker for poor prognosis. Utilizing a recently developed extendable blocking probe assay, we analyzed the BRAF mutation status in a CRC patient cohort (N = 571) using tissue-derived RNA as the starting material. From the same RNA samples, we measured the relative SPINK1 expression levels using a quantitative real-time PCR method. Expression of mutant BRAF V600E correlated with poor prognosis, as did low expression of SPINK1 mRNA. Further, BRAF V600E correlated negatively with SPINK1 levels. In order to investigate the effect of MAPK pathway-targeted therapies on SPINK1 secretion, we conducted in vitro studies using both wild-type and V600E CRC cell lines. BRAF inhibitor vemurafenib, and subsequent MAPK pathway inhibitors trametinib and SCH772984, significantly increased SPINK1 secretion in V600E CRC cell lines Colo205 and HT-29 with a concomitant decrease in trypsin-1 and -2 secretion. Notably, no SPINK1 increase or trypsin-1 decrease was observed in BRAF wild-type CRC cell line Caco-2 in response to MAPK pathway inhibitors. In further mechanistic studies, we observed that only trametinib was able to diminish completely both MEK and ERK phosphorylation in the V600E CRC cells. Furthermore, the key regulator of integrated stress response, activating transcription factor 4 (ATF-4), was downregulated both at mRNA and at protein level in response to trametinib treatment. In conclusion, these data suggest that sustained inhibition of not only MAPK pathway activation, but also ATF-4 and trypsin, might be beneficial in the therapy of BRAF V600E-mutant CRC and that SPINK1 levels may serve as an indicator of therapy response.

Serine protease inhibitor Kazal type 1 (SPINK1) downregulates E-cadherin and induces EMT of hepatoma cells to promote hepatocellular carcinoma metastasis via the MEK/ERK signaling pathway

OBJECTIVE

To investigate serine protease inhibitor Kazal type 1 (SPINK1) expression and its influence on the prognosis of human hepatocellular carcinoma (HCC) and to explore the underlying molecular mechanisms involved.

METHODS

Altogether 80 patients with HCC who underwent curative resection were followed up for a median of 58.6 months. SPINK1 expression was detected in the primary HCC samples by immunohistochemistry. Its role in tumor invasion and metastasis was evaluated in vitro by gene silencing using a small interfering RNA-mediated approach, recombinant SPINK1 and U0126 (an inhibitor of MEK/ERK). The proteins in the MEK/ERK signaling pathway were detected by Western blot.

RESULTS

Patients with high SPINK1 expression showed poor overall survival (P = 0.0001) and recurrence-free survival (P = 0.001) compared with those with low SPINK1 expression. The suppression of SPINK1 resulted in reduced cell migration and invasion. SPINK1 overexpression was significantly associated with increased cell migration and invasion in vitro. Furthermore, SPINK1 promoted cancer cells motility and epithelial-mesenchymal transition (EMT) via the mitogen-activated protein kinase kinase (MAPK) and extracellular regulated kinase (ERK) pathway, resulting in increased vimentin expression and decreased E-cadherin expression.

CONCLUSION

SPINK1 may be an oncogene that induces EMT via the MEK/ERK pathway and is a potential target for HCC therapy.

Genetically Determined Chronic Pancreatitis but not Alcoholic Pancreatitis Is a Strong Risk Factor for Pancreatic Cancer

OBJECTIVE

To study if chronic pancreatitis (CP) is a risk factor for pancreatic cancer.

METHODS

Through a cohort and a case-control study design, CP and other important risk factors including smoking, diabetes, alcohol, obesity, and genetic mutations were studied for their association with pancreatic cancer.

RESULTS

In the cohort study, 402 patients with CP were included. During 3967.74 person-years of exposure, 5 of the 402 patients (4 idiopathic CP, 1 hereditary CP) developed pancreatic cancer after 16.60 ± 3.51 years of CP. The standardized incidence ratio was 121. In the case-control study, 249 pancreatic cancer patients and 1000 healthy controls were included. Of the 249 patients with pancreatic cancer, 24 had underlying idiopathic CP, and none had alcoholic pancreatitis. SPINK1 gene mutation was present in 16 of 26 patients with idiopathic CP who had pancreatic cancer. Multivariable analysis showed CP (odds ratio [OR], 97.67; 95% confidence interval [CI], 12.69-751.36), diabetes (>4 years duration) (OR, 3.05; 95% CI, 1.79-5.18), smoking (OR, 1.93; 95% CI, 1.38-2.69) as significant risk factors for pancreatic cancer. The population attributable risk was 9.41, 9.06, and 9.50 for diabetes, CP, and smoking, respectively.

CONCLUSIONS

Genetically determined CP but not alcoholic CP is a strong risk factor for pancreatic cancer.

SPINK6 Promotes Metastasis of Nasopharyngeal Carcinoma via Binding and Activation of Epithelial Growth Factor Receptor

Nasopharyngeal carcinoma has the highest rate of metastasis among head and neck cancers, and distant metastasis is the major reason for treatment failure. The underlying molecular mechanisms of nasopharyngeal carcinoma metastasis are not fully understood. Here, we report the identification of serine protease inhibitor Kazal-type 6 (SPINK6) as a functional regulator of nasopharyngeal carcinoma metastasis via EGFR signaling. SPINK6 mRNA was upregulated in tumor and highly metastatic nasopharyngeal carcinoma cells. Immunohistochemical staining of 534 nasopharyngeal carcinomas revealed elevated SPINK6 expression as an independent unfavorable prognostic factor for overall, disease-free, and distant metastasis-free survival. Ectopic SPINK6 expression promoted in vitro migration and invasion as well as in vivo lymph node metastasis and liver metastasis of nasopharyngeal carcinoma cells, whereas silencing SPINK6 exhibited opposing effects. SPINK6 enhanced epithelial-mesenchymal transition by activating EGFR and the downstream AKT pathway. Inhibition of EGFR with a neutralizing antibody or erlotinib reversed SPINK6-induced nasopharyngeal carcinoma cell migration and invasion. Erlotinib also inhibited SPINK6-induced metastasis in vivo Notably, SPINK6 bound to the EGFR extracellular domain independent of serine protease-inhibitory activity. Overall, our results identified a novel EGFR-activating mechanism in which SPINK6 has a critical role in promoting nasopharyngeal carcinoma metastasis, with possible implications as a prognostic indicator in nasopharyngeal carcinoma patients. Cancer Res; 77(2); 579-89. ©2016 AACR.

The expression profile and prognostic value of SPINK1 in initially diagnosed bone metastatic prostate cancer

BACKGROUND

SPINK1 has been described to be mutually exclusively expressed in prostate cancer (PCa), but its expression profiles and the probable roles in bone metastatic PCa have not been thoroughly explored.

METHODS

Total of 155 biopsy specimens from initially diagnosed bone metastatic PCa were obtained between 2009.1 and 2012.12. SPINK1 and ERG were detected by using immunohistochemical staining. Factors included age, ECOG score, clinical T stage, Gleason scores (GS), expression of SPINK1 and ERG, baseline PSA, baseline ALP, baseline HGB and PSA normalization, and the association of SPINK1 and ERG with clinical outcomes (CRPC-free survival and overall survival) were analyzed.

RESULTS

Totally, SPINK1 and ERG were mutually independently expressed in the primary tissues of those patients, and their positivity were only 13.5% (21/155) and 10.9% (17/155), respectively. Positive expression of SPINK1 was completely detected in cases with primary Gleason score 4 or 5; on the contrary, the frequency of ERG was much lower. Correlative analysis only found that SPINK1 was linked with PSA response to androgen deprivation therapy (χ(2)  = 11.101, P = 0.001). Survival analysis showed that, ERG was not associated with clinical outcomes in all cases, especially in cases with higher GS (8-10) (n = 90); but SPINK1 was an independent prognostic factor which was associated with adverse CFS of patients with GS 8-10 (CFS: HR = 5.141, 95%CI: 1.108-25.552, P = 0.017).

CONCLUSIONS

It is the first time to simultaneously detect SPINK1 and ERG expression in initially diagnosed bone metastatic PCa. The over-expression of SPINK1 was not only related to poor PSA response, but also significantly associated with the occurrence of CRPC, especially in those with much more aggressive phenotype (GS 8-10). So, SPINK1 could be considered as a useful prognostic predictor for bone metastatic PCa at the time of diagnosis, and further prospective studies are needed to verify the conclusions. Prostate 76:823-833, 2016. © 2016 Wiley Periodicals, Inc.

Emerging Roles of SPINK1 in Cancer

BACKGROUND

Tumor-associated trypsin inhibitor (TATI) was originally isolated from the urine of a patient with ovarian cancer. It was later shown to be produced by many other tumors and several normal tissues. It had earlier been isolated from the pancreas and was hence called pancreatic secretory trypsin inhibitor (PSTI). It belongs to a family of protease inhibitors presently called serine peptidase inhibitor Kazal type (SPINK). In the SPINK family TATI/PSTI is SPINK1, which is the name used in this review.

CONTENT

In addition to being a protease inhibitor, SPINK1 also acts as an acute-phase reactant and a growth factor. Furthermore, it has been shown to modulate apoptosis. Overexpression of SPINK1 predicts an unfavorable outcome in several cancers and determination of SPINK1 in serum can be used to identify patients at increased risk of aggressive disease. Thus serum SPINK1 can be used as a prognostic tumor marker. Because SPINK1 acts as a growth factor and an inhibitor of apoptosis in some cancers, it has also been suggested that it can be a therapeutic target in cancer. However, because SPINK1 is the major physiological inhibitor of trypsin, inhibition of SPINK1 may increase the risk of pancreatitis.

SUMMARY

Taking into account the many functions of SPINK1, assessing the role of SPINK1 in cancer has several potentially important clinical applications ranging from a biomarker to a potential new target for cancer therapy.

Serine Protease Inhibitor Kazal Type 1 (SPINK1) Promotes Proliferation of Colorectal Cancer Through the Epidermal Growth Factor as a Prognostic Marker

Serine protease inhibitor Kazal type-1 (SPINK1), a trypsin kinase inhibitor, is involved in inflammation, cell proliferation and carcinogenesis. The role and association between SPINK1, EGFR and Ki-67 in colorectal adenoma (CRA) and colorectal cancer (CRC) are still unknown. In this study, we used immunohistochemical stain to evaluate expression of SPINK1, EGFR and Ki-67 proteins in 30 CRA and 53 CRC patients semiquantitatively, and then analyzed their correlation with clinicopathologic parameters. Our results revealed that SPINK1 expression was noted in the upper and basal parts of the crypts in CRA and was more intensely related with cellular atypia. EGFR expression was found in 13 out of 30 adenomas, including 9 out of 15 adenomas with dysplasia or synchronous CRC (60 %), and 4 out of 15 adenomas without dysplasia (26.7 %). In CRC, high SPINK1 expression was significantly associated with males (p = 0.041) and advanced disease stage (p = 0.015). EGFR positivity was significantly correlated with higher T stage (p = 0.004) and disease stage (stage I-IV, p = 0.017; early vs. late, p = 0.015). Pearson's correlation showed positive correlation between the SPINK1 intensity and EGFR immunoreactivity (p = 0.011), and Ki-67 and SPINK1 intensity or percentage (p = 0.017 and p = 0.039 respectively). In Kaplan-Meier analyses, patients with high SPINK1 intensity tended to have shorter overall survival (p = 0.03). Concomitant expression of high SPINK1 intensity and EGFR was also identified as being associated with poor prognosis (p = 0.015). In conclusion, high SPINK1 expression is associated with advanced stage and poor prognosis. There is positive correlation between high SPINK1 expression, EGFR immunoreactivity, and high Ki-67 labeling index. The SPINK1 protein seems to play a role in tumor proliferation and malignant transformation through the EGFR pathway. SPINK1 may serve as a prognostic biomarker in therapeutic targeting in the future.

FOXP1 and SPINK1 reflect the risk of cirrhosis progression to HCC with HBV infection

BACKGROUND

Hepatocellular carcinoma (HCC) deriving from cirrhosis with HBV infection harbors higher morbidity and poor prognosis. The diagnosis of HCC at its early stage is essential for improving the effect of treatment and survival rate of patients.

METHOD

Affymetrix GeneChip was practiced to establish gene expression profile and significance analysis of microarray (SAM) as well as prediction analysis of microarray (PAM) was utilized to screen candidate marker genes in tissue of carcinoma and para-cancerous with cirrhosis from 15 hepatitis B virus (HBV) related HCC patients.

RESULT

Total 497 differential genes were selected by microarray (fold change >2; P value<0.01). Then 162 significant genes were determined by SAM (fold change -1.46 to 1.28). A number of 8-genes showing "poor risk signature" was validated with threshold of 6.2, which was associated with cirrhosis progressing to HCC. Only 3 down-regulated and 2 up-regulated predictor genes had statistical difference in HCC and cirrhosis groups by RT-PCR (P value<0.01). Forkhead box protein 1 (FOXP1) and serine protease inhibitor Kazal-type 1 (SPINK1) proteins were found significantly increased in carcinoma tissues than para-cancerous cirrhotic tissues by IH and WB.

CONCLUSION

Over-expression of FOXP1 and SPINK1 may participate in the carcinogenesis of HBV related cirrhosis. They could use as potential biomarkers for diagnosing early HCC.

Application of an electrochemical immunosensor with a MWCNT/PDAA modified electrode for detection of serum trypsin

Objective: To establish an electrochemical immunosensor for the determination of serum trypsin levels using a multiwall carbon nanotubes (MWCNTs)-composite-modified electrode. Method: A MWCNT composite coated on the surface of bare gold electrodes was used for fixation of an anti-trypsin antibody. The assembly process and the performance indicators, including sensitivity, linear range of detection, anti-jamming performance, and stability, of the electrochemical immunosensor were examined by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Results: With optimized experimental conditions, the difference of the current value measured by differential pulse voltammetry (DPV) showed a linear relationship with the concentration of serum trypsin within 0.10–100 ng/mL. The detection limit for trypsin using this sensor was 0.002 ng/mL. Conclusions: The electrochemical immunosensor built using the MWCNT-composite-modified electrode is simple to operate and has a fast response time, along with a wide linear range, high sensitivity, and accuracy, making it suitable for serum trypsin detection.

CBX7 modulates the expression of genes critical for cancer progression

Background

We have previously shown that the expression of CBX7 is drastically decreased in several human carcinomas and that its expression progressively decreases with the appearance of a highly malignant phenotype. The aim of our study has been to investigate the mechanism by which the loss of CBX7 expression may contribute to the emergence of a more malignant phenotype.

Methods

We analyzed the gene expression profile of a thyroid carcinoma cell line after the restoration of CBX7 and, then, analyzed the transcriptional regulation of identified genes. Finally, we evaluated the expression of CBX7 and regulated genes in a panel of thyroid and lung carcinomas.

Results

We found that CBX7 negatively or positively regulates the expression of several genes (such as SPP1, SPINK1, STEAP1, and FOS, FOSB, EGR1, respectively) associated to cancer progression, by interacting with their promoter regions and modulating their transcriptional activity. Quantitative RT-PCR analyses in human thyroid and lung carcinoma tissues revealed a negative correlation between CBX7 and its down-regulated genes, while a positive correlation was observed with up-regulated genes.

Conclusion

In conclusion, the loss of CBX7 expression might play a critical role in advanced stages of carcinogenesis by deregulating the expression of specific effector genes.

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.

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.

Elevated expression of MGb2-Ag/TRAK1 is correlated with poor prognosis in patients with colorectal cancer

PURPOSE

MGb2, a mouse-derived monoclonal antibody specific to gastric carcinoma, was developed in our laboratory. Nevertheless, the potential role of MGb2-antigen/TRAK1 (MGb2-Ag/TRAK1) in colorectal cancer (CRC) is unclear. The aim of this study was to investigate the relationship between MGb2-Ag/TRAK1 expression and the clinicopathological characteristics of CRC. The potential utility of MGb2-Ag/TRAK1 expression as a prognostic indicator was also evaluated.

METHODS

Immunohistochemistry and western blot were used to detect MGb2-Ag/TRAK1 expression in 140 CRC tissues. The relationship between MGb2-Ag/TRAK1 expression and clinicopathological characteristics and postoperative survival time was statistically analyzed.

RESULTS

MGb2-Ag/TRAK1 expression in CRC tissues was significantly higher than in normal tissues and was positively correlated with tumor differentiation (p = 0.006), invasion (p = 0.049), and pathological stage (p = 0.032). There was no significant difference between MGb2-Ag/TRAK1 expression and the age or gender of the patient, lymphatic invasion, or distant metastasis (p = 0.586, 0.308, 0.910, and 0.068, respectively). The survival time of CRC patients with high expression of MGb2-Ag/TRAK1 was shorter than the survival time of patients with low MGb2-Ag/TRAK1 expression. Both univariate and multivariate analyses showed that tumor differentiation and MGb2-Ag/TRAK1 expression were two independent and prognostic factors for CRC (p < 0.001).

CONCLUSIONS

MGb2-Ag/TRAK1 may play an important role in the development of CRC and may be a valuable prognostic indicator of CRC.

Effects of radiation therapy on tissue and serum concentrations of tumour associated trypsin inhibitor and their prognostic significance in rectal cancer patients

BACKGROUND

We have previously demonstrated that elevated concentrations of tumour-associated trypsin inhibitor (TATI) in both tumour tissue (t-TATI) and in serum (s-TATI) are associated with a poor prognosis in colorectal cancer patients. It was also found that s-TATI concentrations were lower in patients with rectal cancer compared to patients with colon cancer. In this study, we investigated the effects of neoadjuvant radiotherapy (RT) on concentrations of t-TATI and s-TATI in patients with rectal cancer.

METHODS

TATI was analysed in serum, normal mucosa and tumour tissue collected at various time points in 53 rectal cancer patients enrolled in a case-control study where 12 patients received surgery alone, 20 patients 5 × 5 Gy (short-term) preoperative RT and 21 patients 25 × 2 Gy (long-term) preoperative RT. T-TATI was analysed by immunohistochemistry and s-TATI was determined by an immunofluorometric assay. Mann-Whitney U test and Wilcoxon Z (Z) test were used to assess t-TATI and s-TATI concentrations in relation to RT. Spearman's correlation (R) test was used to explore the associations between t-TATI, s-TATI and clinicopathological parameters. Overall survival (OS) according to high and low t-TATI and s-TATI concentrations was estimated by classification and regression tree analysis, Kaplan-Meier analysis and the log rank test.

RESULTS

RT did not affect concentrations of t-TATI or s-TATI. In patients receiving short-term but not long-term RT, s-TATI concentrations were significantly higher 4 weeks post surgery than in serum drawn prior to surgery (Z = -3.366, P < 0.001). T-TATI expression correlated with male gender (R = 0.406, P = 0.008). High t-TATI expression in surgical specimens was associated with a significantly shorter OS (P = 0.045). S-TATI concentrations in serum drawn at all time points were associated with an impaired OS (P = 0.035 before RT, P = 0.001 prior to surgery, P = 0.043 post surgery). At all time points, s-TATI correlated with higher age (P < 0.001-0.021) and with increased s-creatinine concentrations assessed prior to surgery (P = 0.041).

CONCLUSIONS

The results presented here further validate the utility of t-TATI and s-TATI as prognostic biomarkers in patients with rectal cancer, independent of neoadjuvant RT.

High expression of testes-specific protease 50 is associated with poor prognosis in colorectal carcinoma

Background

Testes-specific protease 50 (TSP50) is normally expressed in testes and abnormally expressed in breast cancer, but whether TSP50 is expressed in colorectal carcinoma (CRC) and its clinical significance is unclear. We aimed to detect TSP50 expression in CRC, correlate it with clinicopathological factors, and assess its potential diagnostic and prognostic value.

Methodology/Principal Findings

TSP50 mRNAs and proteins were detected in 7 CRC cell lines and 8 CRC specimens via RT-PCR and Western blot analysis. Immunohistochemical analysis of TSP50, p53 and carcinoembryonic antigen (CEA) with tissue microarrays composed of 95 CRCs, 20 colorectal adenomas and 20 normal colorectal tissues were carried out and correlated with clinicopathological characteristics and disease-specific survival for CRC patients. There was no significant correlation between the expression levels of TSP50 and p53 (P = 0.751) or CEA (P = 0.663). Abundant expression of TSP50 protein was found in CRCs (68.4%) while it was poorly expressed in colorectal adenomas and normal tissues (P<0.0001). Thus, CRCs can be distinguished from them with high specificity (92.5%) and positive predictive value (PPV, 95.6%). The survival of CRC patients with high TSP50 expression was significantly shorter than that of the patients with low TSP50 expression (P = 0.010), specifically in patients who had early-stage tumors (stage I and II; P = 0.004). Multivariate Cox regression analysis indicated that high TSP50 expression was a statistically significant independent risk factor (hazard ratio  = 2.205, 95% CI = 1.214–4.004, P = 0.009).

Conclusion

Our data demonstrate that TSP50 is a potential effective indicator of poor survival for CRC patients, especially for those with early-stage tumors.

Global expression study in colorectal cancer on proteins with alkaline isoelectric point by two-dimensional difference gel electrophoresis

Colorectal cancer is one of the leading causes of cancer death worldwide. To identify candidates for biomarkers and therapeutic targets, we investigated the proteome of colorectal cancer tissues. Using 2D-DIGE in combination with our original large format electrophoresis apparatus, we compared surgically resected normal and tumor tissues from 53 patients with colorectal cancer. We focused on proteins with an alkaline pI using IPG gels for the alkaline range. We observed 1687 protein spots, and found 100 spots with statistical (p<0.01) and significant (>2-fold) differences between the normal and the tumor tissue groups. Among these 100 protein spots, five showed a different intensity between tumor tissues from the stage-II and the stage-III patients. MS experiments revealed that these 100 protein spots corresponded to 58 unique proteins. These included six proteins which had not been previously reported to be associated with colorectal cancer. Among these proteins, five were not reported in any type of malignancy. IEF/western blotting confirmed the differences in protein expression between the normal and the tumor tissues. These results may provide an insight for biomarker development and drug target discovery in colorectal cancer.