S100P is a novel marker to identify intraductal papillary mucinous neoplasms

S100 Proteins in Pancreatic Cancer: Current Knowledge and Future Perspectives

Pancreatic cancer (PC) is a highly malignant tumor occurring in the digestive system. Currently, there is a lack of specific and effective interventions for PC; thus, further exploration regarding the pathogenesis of this malignancy is warranted. The S100 protein family, a collection of calcium-binding proteins expressed only in vertebrates, comprises 25 members with high sequence and structural similarity. Dysregulated expression of S100 proteins is a biomarker of cancer progression and prognosis. Functionally, these proteins are associated with the regulation of multiple cellular processes, including proliferation, apoptosis, growth, differentiation, enzyme activation, migration/invasion, Ca2+ homeostasis, and energy metabolism. This review highlights the significance of the S100 family in the diagnosis and prognosis of PC and its vital functions in tumor cell metastasis, invasion and proliferation. A further understanding of S100 proteins will provide potential therapeutic targets for preventing or treating PC.

Discovery of novel small molecule inhibitors of S100P with in vitro anti-metastatic effects on pancreatic cancer cells

S100P, a calcium-binding protein, is known to advance tumor progression and metastasis in pancreatic and several other cancers. Herein is described the in silico identification of a putative binding pocket of S100P to identify, synthesize and evaluate novel small molecules with the potential to selectively bind S100P and inhibit its activation of cell survival and metastatic pathways. The virtual screening of a drug-like database against the S100P model led to the identification of over 100 clusters of diverse scaffolds. A representative test set identified a number of structurally unrelated hits that inhibit S100P-RAGE interaction, measured by ELISA, and reduce in vitro cell invasion selectively in S100P-expressing pancreatic cancer cells at 10 μM. This study establishes a proof of concept in the potential for rational design of small molecule S100P inhibitors for drug candidate development.

Very early recurrence following pancreaticoduodenectomy in patients with ampullary cancer

We aimed to identify the factors for very early recurrence (within 6 months) of ampullary cancer following curative resection and to compare the immunohistochemical expression rate of various antibodies between the 2 main histologic subtypes of ampullary adenocarcinoma.In this retrospective study, the postoperative outcomes and clinicopathologic factors for very early recurrence that occurred in 14 of 93 patients who underwent pancreaticoduodenectomy (PD) for ampullary adenocarcinoma between January 2002 and August 2014 were analyzed. Thereafter, we identified the factors associated with very early recurrence following surgery. Additionally, we compared the expression rates of CK7, CK20, MUC1, MUC2, MUC5AC, MUC6, S100P, and CDX2 between the 2 main histologic subtypes of ampullary adenocarcinoma (NCC2019-0138).The patients who underwent PD for ampullary cancer were divided into 2 groups: very early recurrence and others. Compared with the other patients, the 14 patients (32.6%) who developed very early recurrence had shorter median disease-free survival (4.2 vs 49.7 months, P = .001) and overall survival (18.2 vs 113.7 months, P < .001). Large tumor, lymph node metastasis, and pancreatobiliary type were independently associated with very early recurrence of ampullary cancer following PD.Large tumor, lymph node metastasis, and pancreatobiliary type were the independent risk factors for very early recurrence of ampullary cancer following curative resection. Therefore, ampullary cancer patients with these factors should be considered to receive aggressive adjuvant treatment and frequent post-operative follow-up.

S100P in Duodenal Fluid Is a Useful Diagnostic Marker for Pancreatic Ductal Adenocarcinoma

OBJECTIVES

The development of an effective screening method for pancreatic ductal adenocarcinoma (PDAC) is of paramount importance. This study assessed the diagnostic utility in pancreatic diseases of duodenal markers during upper gastrointestinal endoscopy (GIE) or endoscopic ultrasonography.

METHODS

This study prospectively enrolled 299 consecutive participants, including 94 patients with PDACs, 144 patients with other pancreatic diseases, and 61 normal individuals as control subjects. All subjects underwent upper GIE or endoscopic ultrasonography either at Kyushu University Hospital (Fukuoka, Japan) or the Mayo Clinic (Jacksonville, Fla) from October 2011 to July 2014. Duodenal fluid (DF) was collected without secretin stimulation and of carcinoembryonic antigen and S100 calcium-binding protein P (S100P) concentrations were measured.

RESULTS

Concentrations of S100P in DF were significantly higher in patients with PDAC and chronic pancreatitis than in control subjects (P < 0.01). A logistic regression model that included age found that the sensitivity and specificity of S100P concentration in diagnosing stages 0/IA/IB/IIA PDAC were 85% and 77%, respectively, with an area under the receiver operating characteristic curve of 0.82. Carcinoembryonic antigen concentrations in DF of patients with pancreatic disease did not differ significantly from control subjects.

CONCLUSIONS

Analysis of S100P concentration in DF, in combination with routine screening upper GIE, may facilitate the detection of PDAC.

Expression and Distribution of Calcium-Binding Protein S100P in Human Placenta during Pregnancy

Background

S100P is a member of the S100 family of calcium-binding proteins, and it participates in pathophysiological events, such as tumor growth and invasion. Based on the striking similarities between trophoblast cells and tumor cells with regard to proliferative and invasive properties, we raised the question of whether and how S100P expresses in trophoblast cells during development. This study aimed to investigate the expression pattern of S100P in the human placenta during pregnancy development.

Materials and Methods

In this experimental study, we collected 16 first-trimester placental tissues, 10 second-trimester placental tissues, and 12 term placentas. The mRNA expression levels of S100P were detected by reverse-transcription-polymerase chain reaction (RT-PCR) and quantitative real-time PCR, the protein expression levels were detected by western blot, and the localization of S100P was measured by immunohistochemical staining. The values obtained from PCR and western blot analysis were expressed as the mean ± SD. Levene’s test was used to test equal variances, and one-way analysis of variance (ANOVA) was used to evaluate differences between groups.

Results

Protein and mRNA expression of S100P could be detected in placenta during pregnancy, with minor higher levels in first-trimester (p>0.05). Immunohistochemical staining revealed that S100P protein was strongly expressed in syncytiotrophoblasts, and moderate expression was detected in villous cytotrophoblasts and cytotrophoblast columns. The S100P protein was localized to both cytoplasm and nuclei in syncytiotrophoblasts, while it only existed in the cytoplasm of cytotrophoblasts.

Conclusion

S100P was strongly detected in human placenta during pregnancy. The specific expression and distribution of S100P in human placenta throughout gestation suggested that S100P function might vary with its location in the placenta.

Utility of immunohistochemistry in the pancreatobiliary tract

CONTEXT

Immunohistochemistry has become a useful ancillary study in the identification and classification of pancreatic neoplasms. The diagnostic accuracy has been significantly improved because of the continuous discoveries of tumor-associated biomarkers and the development of effective immunohistochemical panels.

OBJECTIVES

To identify and classify pancreatic neoplasms by immunohistochemistry.

DATA SOURCES

Literature review and authors' research data and personal practice experience were used.

CONCLUSIONS

To better guide therapeutic decisions and predict the prognostic outcome, it is crucial to make an accurate diagnosis of a pancreatic neoplasm. Application of appropriate immunohistochemical panels enables pathologists to differentiate pancreaticobiliary adenocarcinomas from reactive conditions and to identify rare types of pancreatic neoplasms. Knowing the utilities and pitfalls of each tumor-associated biomarker is essential to avoiding a potential diagnostic error because an absolutely cancer-specific biomarker does not exist. This article reviews frequently used tumor-associated biomarkers, provides lists of effective immunohistochemical panels, and recommends a diagnostic algorithm as a standard approach to pancreatic neoplasms.

A meta analysis of pancreatic microarray datasets yields new targets as cancer genes and biomarkers

The lack of specific symptoms at early tumor stages, together with a high biological aggressiveness of the tumor contribute to the high mortality rate for pancreatic cancer (PC), which has a five year survival rate of less than 5%. Improved screening for earlier diagnosis, through the detection of diagnostic and prognostic biomarkers provides the best hope of increasing the rate of curatively resectable carcinomas. Though many serum markers have been reported to be elevated in patients with PC, so far, most of these markers have not been implemented into clinical routine due to low sensitivity or specificity. In this study, we have identified genes that are significantly upregulated in PC, through a meta-analysis of large number of microarray datasets. We demonstrate that the biological functions ascribed to these genes are clearly associated with PC and metastasis, and that that these genes exhibit a strong link to pathways involved with inflammation and the immune response. This investigation has yielded new targets for cancer genes, and potential biomarkers for pancreatic cancer. The candidate list of cancer genes includes protein kinase genes, new members of gene families currently associated with PC, as well as genes not previously linked to PC. In this study, we are also able to move towards developing a signature for hypomethylated genes, which could be useful for early detection of PC. We also show that the significantly upregulated 800+ genes in our analysis can serve as an enriched pool for tissue and serum protein biomarkers in pancreatic cancer.

S100 family signaling network and related proteins in pancreatic cancer (Review)

The occurrence and development of pancreatic cancer is a complex process convoluted by multi-pathogenies, multi-stages and multi-factors. S100 proteins are members of the S100 family that regulate multiple cellular pathways related to pancreatic cancer progression and metastasis. S100 proteins have a broad range of intracellular and extracellular functions, including the regulation of protein phosphorylation and enzyme activity, calcium homeostasis and the regulation of cytoskeletal components and transcriptional factors. S100 proteins interact with receptor for advanced glycation end-products (RAGE), p53 and p21, which play a role in the degradation of the extracellular matrix (ECM) and metastasis, and also interact with cytoskeletal proteins and the plasma membrane in pancreatic cancer progression and metastasis. S100A11 and S100P are significant tumor markers for pancreatic cancer and unfavorable predictors for the prognosis of patients who have undergone surgical resection. Recently, S100A2 has been suggested to be a negative prognostic biomarker in pancreatic cancer, and the expression of S100A6 may be an independent prognostic impact factor. The expression of S100A4 and S100P is associated with drug resistance, differentiation, metastasis and clinical outcome. This review summarizes the role and significance of the S100 family signaling network and related proteins in pancreatic cancer.

Cystic and micropapillary epithelial changes of peribiliary glands might represent a precursor lesion of biliary epithelial neoplasms

A tumorigenic role of peribiliary glands (PBGs) has been suggested recently. This study was performed to clarify the histological characteristics of PBGs showing cystic and micropapillary epithelial changes. From histological sections of a total of 938 autopsy livers, cases with cystic and micropapillary changes of the epithelial cells of intrahepatic PBGs were collected. PBGs with cystic change that lacked micropapillary epithelial changes were referred to as cystic lesion. Mucin staining and immunohistochemical analysis were performed, and the results were compared between cystic and micropapillary (C-P) lesions and cystic lesions. C-P and cystic lesions were observed in 9 (1 %) and 40 (4 %) , respectively. The atypia of micropapillary epithelium was usually mild, but in a single case, invasive adenocarcinoma accompanied a C-P lesion. Abundant mucin expression was observed in all cases of C-P lesion, which was similar to mucinous acini of normal PBGs rather than serous acini. Immunohistochemical analysis showed that MUC5AC was more frequently expressed in C-P lesions than in cystic lesions. Immunohistochemical expression of cyclin D1 and S100P was characteristically found in C-P lesions. Mean Ki-67 labeling index of C-P lesions was significantly higher than that of cystic lesions. The immunoprofile of C-P lesions was similar to that of the branch-type intraductal papillary mucinous neoplasm of the pancreas. These results suggest that C-P lesions may have neoplastic features and might represent a precursor of biliary epithelial neoplasms, including branch-type intraductal papillary neoplasm of the bile duct as well as mucin-producing cholangiocarcinoma, a concept that we have recently proposed.

Pancreatic Cancer: Clinical Significance of Biomarkers

BACKGROUND

Improvement in the prognosis of patients with pancreatic cancer, novel effective screening and diagnostic strategies and treatments are needed. Recent advances in the understanding of pancreatic carcinogenesis and tumor microenvironment have allowed identification of biomarkers for screening, diagnosis and prediction of cancer treatments, including novel therapies targeting specific cancer or stromal cell subpopulations. Personalized therapy in pancreatic cancer is also promising as several drugs such as S1, capecitabine and gemcitabine reportedly have significant therapeutic effects. Predictive markers are thus needed to select patients most likely to benefit from therapies based on gemcitabine or other drugs.

SUMMARY

We review the clinical significance of promising screening, diagnostic, predictive and prognostic biomarkers based on genetic and epigenetic alterations and microRNA abnormalities in pancreatic cancer. We also review new types of biomarkers based on stromal cells, such as pancreatic stellate cells, in the microenvironment of pancreatic cancer.

Risk factors for pancreatic ductal adenocarcinoma specifically stimulate pancreatic duct glands in mice

Diabetes mellitus type 2 and chronic pancreatitis are regarded as risk factors for pancreatic cancer. Pancreatic duct glands (PDGs) were recently described as a new compartment of the major duct in humans and mice. To evaluate the influence of diabetes and chronic pancreatitis on PDGs, cerulein was injected i.p., repetitively over 10 weeks, in mice exhibiting obesity and a type 2 diabetes-like syndrome (B6.V-Lep(ob/ob)) and in lean littermates. By using 5-bromo-2'-deoxyuridine (BrdU), a label-retaining cell population was characterized in PDGs. Cerulein administration led to more BrdU(+) cells in PDGs of obese mice compared with lean mice. The observed increase was specific to PDGs, because BrdU incorporation in cells of the pancreatic duct was not increased. In addition, the expression of distinct tumor markers in PDGs was characterized by Muc5ac, S100P, regenerating islet-derived 3β, 14-3-3 σ, and prostate stem cell antigen immunochemistry. Type 2 diabetes-like syndrome, accompanied by chronic pancreatitis, enhanced nuclear localization of S100P. Both risk factors for pancreatic cancer also induced the production of Muc5ac and the nuclear localization of S100P [corrected]. These results demonstrate that diabetes and chronic pancreatitis jointly enhance BrdU incorporation and production of pancreatic cancer-specific proteins in PDGs. The observed alterations suggest that pancreatic tumors might originate from the newly discovered histomorphological structures, called PDGs, which could represent a target for future anticancer therapies.

Clinicopathological significance of S100 protein expression in cholangiocarcinoma

BACKGROUND AND AIM

Cholangiocarcinoma arising in the large bile ducts undergoes a multistep carcinogenesis process in chronic biliary diseases, and biliary intraepithelial neoplasia is known as a precursor lesion. This study examined the expression of S100 proteins in the multistep cholangiocarcinogenesis to clarify their clinicopathological significance.

METHODS

Immunohistochemical analysis was performed for the expression of S100A2, S100A4, S100A6, and S100P. Bile concentrations of S100P were measured using enzyme-linked immunosorbent assay.

RESULTS

The immunohistochemical expression of the S100 proteins was increased in biliary intraepithelial neoplasia as well as invasive adenocarcinoma of perihilar cholangiocarcinoma. Among the proteins, S100P expression was most drastically increased during the multistep carcinogenesis process. In cases with perihilar and extrahepatic cholangiocarcinoma, the immunohistochemical expression of S100A2 in cholangiocarcinoma cells significantly correlated with the histological grade, lymph node metastasis, clinical stage, and a poor survival rate of the patients. The bile levels of S100P were increased significantly in patients with cholangiocarcinoma compared with those in patients with lithiasis. Receiver operating characteristic curve analysis showed that S100P bile concentration was an indicator of cholangiocarcinoma with a sensitivity of 93% and a specificity of 70%.

CONCLUSIONS

These results suggest that S100P may be useful for the detection of cholangiocarcinoma as tissue and bile biomarkers, and the immunohistochemical expression of S100A2 is a potential prognostic marker in cholangiocarcinoma patients.

Differential proteomic analysis of cancer stem cell properties in hepatocellular carcinomas by isobaric tag labeling and mass spectrometry

Malignant tumors are relatively resistant to treatment due to their heterogeneous nature, drug resistance, and tendency for metastasis. Recent studies suggest that a subpopulation of cancer cells is responsible for the malignant outcomes. These cells are considered as cancer stem cells (CSC). Although a number of molecules have been identified in different cancer cells as markers for cancer stem cells, no promising markers are currently available for hepatocellular carcinoma cells. In this study, two clones of Hep3B cell lines were functionally characterized as control or CSC-like cells, based on properties including spheroid formation, drug resistance, and tumor initiation. Furthermore, their protein expression profiles were investigated by isobaric tags for relative and absolute quantitation (iTRAQ), and a total of 1,127 proteins were identified and quantified from the combined fractions; 50 proteins exhibited at least 2-fold differences between these two clones. These 50 proteins were analyzed by GeneGo and were found to be associated with liver neoplasms, hepatocellular carcinoma (HCC), and liver diseases. They were also components of metabolic pathways, immune responses, and cytoskeleton remodeling. Among these proteins, the expressions of S100P, S100A14, and vimentin were verified in several HCC cell lines, and their expressions were correlated with tumorigenicity in HCC cell lines. The functional significance of vimentin and S100A14 were also investigated and verified.

A minimally invasive and simple screening test for detection of pancreatic ductal adenocarcinoma using biomarkers in duodenal juice

OBJECTIVES

The aim of this study was to establish a minimally invasive and simple screening test for detection of pancreatic ductal adenocarcinoma (PDAC) using duodenal juice (DJ).

METHODS

Duodenal juice was collected prospectively before endoscopic retrograde cholangiopancreatography in 46 patients. A protease inhibitor was not added to the samples collected during the initial 2.5 minutes but was added in the latter 2.5 minutes. Thereafter, secretin was administered intravenously, and DJ was subsequently collected for additional 10 minutes. The sensitivities of carcinoembryonic antigen (CEA), S100 calcium-binding protein P (S100P), and interleukin 8 in DJ and pancreatic juice were assessed.

RESULTS

There were 30 patients with PDAC and 16 with benign lesions. It was possible to collect an adequate amount of DJ without secretin administration. In the PDAC group, CEA concentrations in DJ were significantly higher than those in the benign group, even without the use of a protease inhibitor. S100P levels in DJ in the PDAC group were significantly higher than those in the benign group in the presence of the protease inhibitor.

CONCLUSIONS

Duodenal juice collection during routine upper endoscopy and assessments of CEA and S100P in DJ might become a useful screening test for detection of PDAC.

S100P expression in response to sex steroids during the implantation window in human endometrium

BACKGROUND

S100P, a protein originally detected in the human placenta, has been found to play an important role in the development and invasion of tumors. Interestingly, we have recently discovered using data mining that S100P was considerably up-regulated during the window of implantation in the human endometrium, but little further information has been available.

METHODS

Real-time PCR and immunofluorescence were performed to examine the expression and location of S100P in the human endometrium and endometrial cells. Estrogen and progesterone were added to the cultured cells to test the response of S100P to sex steroids.

RESULTS

A dramatic peak, approximately a 100-fold increase in comparison with the proliferative and early- and late-secretory phases, was observed in the endometrium during the mid-secretory phase, which corresponds to the time of embryo implantation. Progesterone regulated the expression of S100P in both primary endometrial epithelial and stromal cells, but estrogen had no significant effect.

CONCLUSIONS

The results indicate that S100P participates in the periodic change of the endometrium under the regulation of progesterone, may be used as a unique biomarker of the receptive endometrium and play an important role in embryo implantation.

Reevaluation and identification of the best immunohistochemical panel (pVHL, Maspin, S100P, IMP-3) for ductal adenocarcinoma of the pancreas

CONTEXT

Differentiation of ductal adenocarcinoma of the pancreas from nonneoplastic pancreatic tissues can be challenging, especially in small biopsy and fine-needle aspiration specimens.

OBJECTIVE

To investigate the utility of 26 immunohistochemical markers (CAM 5.2, CK [cytokeratin] 7, CK20, CK17, CK19, MUC1, MUC2, MUC4, MUC5AC, MUC6, p53, DPC4/SMAD4, CDX2, pVHL [von Hippel-Lindau tumor suppressor gene protein], S100P, IMP-3 [insulin-like growth factor 2 messenger RNA binding protein 3], maspin, mesothelin, claudin 4, claudin 18, annexin A8, fascin, PSCA [prostate stem cell antigen], MOC31, CEA [carcinoembryonic antigen], and CA19-9 [cancer antigen 19-9]) in the diagnosis of ductal adenocarcinoma of the pancreas.

DESIGN

Immunohistochemical staining for these markers was performed in 60 cases of pancreatic ductal adenocarcinoma on routine and tissue microarray sections. In addition, immunohistochemical staining for maspin, S100P, IMP-3, and pVHL was performed on cell blocks from 67 pancreatic fine-needle aspiration cases, including 44 cases of pancreatic ductal adenocarcinoma.

RESULTS

The results demonstrated that (1) more than 90% of cases of ductal adenocarcinoma were positive for maspin, S100P, and IMP-3; (2) nearly all adenocarcinoma cases were negative for pVHL, whereas nonneoplastic ducts and acini were positive for pVHL in all cases; (3) normal/reactive pancreatic ducts were frequently positive for CK7, CK19, MUC1, MUC6, CA19-9, MOC31, PSCA, mesothelin, annexin A8, claudin 4, and claudin 18; (4) normal pancreatic ducts were usually negative for IMP-3, maspin, S100P, CK17, MUC2, MUC4, and MUC5AC; (5) 60% of adenocarcinomas were negative for DPC4/SMAD4; and (6) strong background staining was frequently seen with fascin, PSCA, and annexin A8.

CONCLUSIONS

pVHL, maspin, S100P, and IMP-3 constitute the best diagnostic panel of immunomarkers for confirming the diagnosis of pancreatic ductal adenocarcinoma in both surgical and fine-needle aspiration specimens.

RNA-Seq quantification of the human small airway epithelium transcriptome

Background

The small airway epithelium (SAE), the cell population that covers the human airway surface from the 6^th generation of airway branching to the alveoli, is the major site of lung disease caused by smoking. The focus of this study is to provide quantitative assessment of the SAE transcriptome in the resting state and in response to chronic cigarette smoking using massive parallel mRNA sequencing (RNA-Seq).

Results

The data demonstrate that 48% of SAE expressed genes are ubiquitous, shared with many tissues, with 52% enriched in this cell population. The most highly expressed gene, SCGB1A1, is characteristic of Clara cells, the cell type unique to the human SAE. Among other genes expressed by the SAE are those related to Clara cell differentiation, secretory mucosal defense, and mucociliary differentiation. The high sensitivity of RNA-Seq permitted quantification of gene expression related to infrequent cell populations such as neuroendocrine cells and epithelial stem/progenitor cells. Quantification of the absolute smoking-induced changes in SAE gene expression revealed that, compared to ubiquitous genes, more SAE-enriched genes responded to smoking with up-regulation, and those with the highest basal expression levels showed most dramatic changes. Smoking had no effect on SAE gene splicing, but was associated with a shift in molecular pattern from Clara cell-associated towards the mucus-secreting cell differentiation pathway with multiple features of cancer-associated molecular phenotype.

Conclusions

These observations provide insights into the unique biology of human SAE by providing quantit-ative assessment of the global transcriptome under physiological conditions and in response to the stress of chronic cigarette smoking.

Using BioMart as a framework to manage and query pancreatic cancer data

We describe the Pancreatic Expression Database (PED), the first cancer database originally designed based on the BioMart infrastructure. The PED portal brings together multidimensional pancreatic cancer data from the literature including genomic, proteomic, miRNA and gene expression profiles. Based on the BioMart 0.7 framework, the database is easily integrated with other BioMart-compliant resources, such as Ensembl and Reactome, to give access to a wide range of annotations alongside detailed experimental conditions. This article is intended to give an overview of PED, describe its data content and work through examples of how to successfully mine and integrate pancreatic cancer data sets and other BioMart resources.

Database URL:http://www.pancreasexpression.org