CHRONIC PANCREATITIS IN A PATIENT WITH THE p.Asn34Ser HOMOZYGOUS SPINK1 MUTATION--OWN EXPERIENCE

Chronic pancreatitis (CP) is characterized by progressive damage to the exocrine and endocrine cell structures and pancreatic ducts with subsequent fibrosis of the organ. Patients with no apparent etiological factor are classified as having idiopathic CP (ICP). Genetic studies indicate the importance of mutations in the serine protease inhibitor, Kazal type 1 gene (SPINK1) in the pathogenesis of CP This report describes a case of a 29-year-old Polish-Vietnamese patient with the p.Asn34Ser (p.N34S) homozygous mutation in the SPINK1 gene. The patient was hospitalized due to pain of average intensity in the epigastric area which occurred for the first time in his life. Imaging examination showed the atrophy of the pancreatic parenchyma with the presence of numerous small calcifications and a single calcified lodgement with a diameter of 22 mm in the distal segment of Wirsung 's duct. Clinical interview did not reveal any obvious etiological pancreatitis risk factors implying the causative role of the p.Asn34Ser homozygous mutation of SPINK1 in this case as proven in our investigation.

Investigation of susceptibility genes triggering lachrymal/salivary gland lesion complications in Japanese patients with type 1 autoimmune pancreatitis

Autoimmune pancreatitis (AIP) is a unique form of chronic pancreatitis characterized by high serum IgG4 concentration and a variety of complicating extra-pancreatic lesions. In particular, lachrymal/salivary gland lesions tend to manifest in a highly active AIP disease state, and several genes are speculated to be associated with the onset of this complication. We therefore searched for candidate susceptibility genes related to lachrymal/salivary gland lesions in a genome-wide association study (GWAS) with the GeneChip Human Mapping 500k Array Set (Affymetrix, CA) that was followed by fine mapping of additional single nucleotide polymorphisms (SNPs) in strongly significant genes with TaqMan assays. Venous blood samples were obtained from 50 type 1 AIP patients with lachrymal/salivary gland lesions (A group) and 53 type 1 AIP patients without (B group). The mean values of IgG and IG4 were both significantly different (P<0.05) between the groups. SNPs that showed a significant association with the A group at the genome-wide level (P<0.0001) were identified and subsequently used in fine SNP mapping of candidate genes. In total, five SNPs had a positive association with complicated AIP (most notably rs2284932 [P=0.0000021]) and five SNPs possessed a negative association (particularly rs9371942 [P=0.00000039]). Among them, KLF7, FRMD4B, LOC101928923, and MPPED2 were further examined for complication susceptibility using additional SNPs that were not included in the GWAS. Individual genotyping of KLF7 rs2284932 revealed that the frequency of the minor C allele was significantly increased (P=0.00062, Pc=0.0018, OR=2.98, 95%CI=1.58-5.65) in group A. The minor T allele of rs4473559 in FRMD4 demonstrated a significant association in the A group (P=0.00015, OR=3.38, 95%CI=1.77-7.65). In the LOC101928923 gene, the frequency of the minor C allele of rs4379306 was significantly decreased in group A in both TaqMan and GWAS analyses. Lastly, the minor C allele of MPPED2 rs514644 carried a significantly increased risk of complications. These four genes may be linked with the onset of lachrymal/salivary gland lesions in type 1 AIP patients and require further study.

MiR-21, miR-34a, miR-198 and miR-217 as diagnostic and prognostic biomarkers for chronic pancreatitis and pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma is an aggressive malignancy with late presentation, metastatic potential and very poor prognosis. Therefore, there is an urgent need for novel diagnostic and prognostic biomarkers. MicroRNAs are small non-coding RNAs that post-transcriptionally regulate gene expression. Altered expression of microRNAs has been reported in wide range of malignancies, including pancreatic ductal adenocarcinoma. The aim of this study was to analyze the expression of selected microRNAs in normal pancreas, chronic pancreatitis and pancreatic ductal adenocarcinoma tissues and evaluate their diagnostic and prognostic potential.

FINDINGS

Using quantitative real-time PCR, expression levels of 4 microRNAs were examined in 74 tumor tissues, 18 tissues of chronic pancreatitis and 9 adjacent normal tissues and correlated with clinicopathological features of patients. Expression levels of miR-21, miR-34a and miR-198 were significantly higher, whereas levels of miR-217 were significantly lower in pancreatic ductal adenocarcinomas compared to healthy tissues and tissues of chronic pancreatitis. Moreover, increased expression of miR-21 and miR-198 was significantly associated with shorter disease free survival and overall survival.

CONCLUSIONS

Our data suggest that altered expression of examined microRNAs is related to neoplastic transformation and progression of the disease and these microRNAs could serve as diagnostic and prognostic biomarkers for pancreatic ductal adenocarcinoma.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1373952531543898.

Fucosyltransferase 2 (FUT2) non-secretor status and blood group B are associated with elevated serum lipase activity in asymptomatic subjects, and an increased risk for chronic pancreatitis: a genetic association study

OBJECTIVE

Serum lipase activities above the threefold upper reference limit indicate acute pancreatitis. We investigated whether high lipase activity-within the reference range and in the absence of pancreatitis-are associated with genetic single nucleotide polymorphisms (SNP), and whether these identified SNPs are also associated with clinical pancreatitis.

METHODS

Genome-wide association studies (GWAS) on phenotypes 'serum lipase activity' and 'high serum lipase activity' were conducted including 3966 German volunteers from the population-based Study-of-Health-in-Pomerania (SHIP). Lead SNPs associated on a genome-wide significance level were replicated in two cohorts, 1444 blood donors and 1042 pancreatitis patients.

RESULTS

Initial discovery GWAS detected SNPs within or near genes encoding the ABO blood group specifying transferases A/B (ABO), Fucosyltransferase-2 (FUT2), and Chymotrypsinogen-B2 (CTRB2), to be significantly associated with lipase activity levels in asymptomatic subjects. Replication analyses in blood donors confirmed the association of FUT-2 non-secretor status (OR=1.49; p=0.012) and ABO blood-type-B (OR=2.48; p=7.29×10(-8)) with high lipase activity levels. In pancreatitis patients, significant associations were found for FUT-2 non-secretor status (OR=1.53; p=8.56×10(-4)) and ABO-B (OR=1.69, p=1.0×10(-4)) with chronic pancreatitis, but not with acute pancreatitis. Conversely, carriers of blood group O were less frequently affected by chronic pancreatitis (OR=0.62; p=1.22×10(-05)) and less likely to have high lipase activity levels (OR=0.59; p=8.14×10(-05)).

CONCLUSIONS

These are the first results indicating that ABO blood type-B as well as FUT2 non-secretor status are common population-wide risk factors for developing chronic pancreatitis. They also imply that, even within the reference range, elevated lipase activities may indicate subclinical pancreatic injury in asymptomatic subjects.

Analysis of global gene expression profiles suggests a role of acute inflammation in type 3C diabetes mellitus caused by pancreatic ductal adenocarcinoma

AIMS/HYPOTHESIS

Pancreatic ductal adenocarcinoma (PDAC) can cause type 3C diabetes, known as PDAC-associated diabetes mellitus (PDAC-DM), but the mechanism is unknown. This study aimed to reveal the mechanism.

METHODS

PDAC lesions from patients with or without PDAC-DM (n = 4 in each group) were individually profiled for 23,512 mRNAs with microarrays. Bioinformatic analysis and in vivo and in vitro assays were then conducted.

RESULTS

We determined that 2,778 genes were differentially expressed; over-representation of ten genes was validated with quantitative RT-PCR. The analysis of gene ontology showed that the differentially expressed secretory genes were related mainly to inflammation. High levels of a marker of inflammation (C-reactive protein [CRP]) and an inflammatory mediator (TNF super-family member 13 [TNFSF13]) were found in the serum of patients with PDAC-DM. After surgical resection of PDAC lesions, CRP and TNFSF13 levels significantly decreased (p < 0.01). Furthermore, we found that the levels of TNFSF13 in PDAC lesions and TNFSF13 and CRP in serum were significantly correlated with the diabetic status of patients with PDAC-DM (p < 0.01). Assays in vivo showed that after exposure to an inhibitor of inflammation (celecoxib), the fasting blood glucose level in the mouse model of PDAC-DM dramatically decreased from 6.9 ± 0.1 to 5.6 ± 0.1 mmol/l in 2-4 days (p < 0.01).

CONCLUSIONS/INTERPRETATION

We found that acute inflammation was involved in the pathogenesis of PDAC-DM. We contend that acute inflammation is a potential target for the diagnosis and treatment of PDAC-DM.

Incidence of post-ERCP pancreatitis from direct pancreatic juice collection in hereditary pancreatitis and familial pancreatic cancer before and after the introduction of prophylactic pancreatic stents and rectal diclofenac

OBJECTIVES

Individuals from hereditary pancreatitis (HP) and familial pancreatic cancer (FPC) kindreds are at increased risk of developing pancreatic cancer. Premalignant molecular changes may be detected in pancreatic juice collected by endoscopic retrograde cholangiopancreatography (ERCP). The objective was to determine the risk of post-ERCP pancreatitis (PEP).

METHODS

A prospective study (1999-2013) was undertaken of 80 ERCPs (24 in HP and 56 in FPC) from 60 individuals and the impact of PEP prophylaxis using a self-expelling pancreatic stent and 50 mg diclofenac per rectum from 2008.

RESULTS

There was no PEP in the HP cohort and 13 (23.2%) PEP from 56 procedures in the FPC cohort (P = 0.0077). Up to 2008 PEP had occurred in 7 (43.8%) of 16 procedures in FPC individuals versus none of 18 procedures in HP individuals (P = 0.0021). After the introduction of prophylaxis, the incidence of PEP fell to 6 (15.0%) of 40 procedures in FPC individuals (P = 0.0347).The odds ratio (95% confidence interval) was 0.23 (0.06-0.84) in favor of prophylaxis (0.035).

CONCLUSIONS

Individuals with HP are at minimal risk for PEP. Although the risk of PEP in individuals with FPC can be reduced by using prophylactic self-expelling stents and diclofenac, it remains too high for routine screening.

[miRNA as a new marker of diabetes mellitus and pancreatic carcinoma progression]

Pancreatic cancer is a disease with increasing incidence and high (and nearly unchanged) lethality that is caused mainly due to its late diagnosis. Risk factors for neoplastic transformation are especially chronic pancreatitis, diabetes mellitus, but also obesity and smoking. The search for suitable early markers becomes a key element of research in this area. Such markers could be microRNAs, short single-stranded RNA molecules functioning as regulators of translation. This article serves as a review of contemporary evidence of microRNA in diabetes mellitus and pancreatic cancer.

Genetic and phenotypic heterogeneity in tropical calcific pancreatitis

Tropical calcific pancreatitis (TCP) is a form of chronic non-alcoholic pancreatitis initially reported in the developing parts of the tropical world. The clinical phenotype of TCP has undergone marked changes since its first description in 1968. The disease is now seen in relatively older people with less severe symptoms. In addition, there are varying reports on the proportion of cases presenting with imaging abnormalities like calcification, ductal dilation, and glandular atrophy. Significant progress has also been made in understanding the etiopathology of TCP. The role of malnutrition and cassava toxicity in its pathogenesis is disproven and few studies have focused on the role of micronutrient deficiency and oxidative stress in the etiopathogenesis of TCP. Emerging evidence support an important role for genetic risk factors in TCP. Several studies have shown that, rather than mutations in trypsinogens, variants in serine protease inhibitor kazal type 1, cathepsin B, chymotrypsin C, cystic fibrosis transmembrane regulator, and carboxypeptidase A1, predict risk of TCP. These studies also provided evidence of mutational heterogeneity between TCP and chronic pancreatitis in Western populations. The current review summarizes recent advances that have implications in the understanding of the pathophysiology and thus, heterogeneity in genotype-phenotype correlations in TCP.

Hereditary pancreatitis: dilemmas in differential diagnosis and therapeutic approach

INTRODUCTION

Hereditary pancreatitis (HP) is a rare, heterogeneous familial disease and should be suspected in any patient who has suffered at least two attacks of acute pancreatitis for which there is no underlying cause and unexplained chronic pancreatitis with a family history in a first- or second-degree relative. Genetic factors have been implied in cases of familial chronic pancreatitis. The most common PRSS1 mutations worldwide are the R122H and N29I variants.

CLINICAL FEATURES

HP usually appears with an acute, a recurrent acute, and a chronic phase, referring to the inflammation of the pancreas and the symptoms' onset and duration. The clinical features of acute pancreatitis begin in childhood and last less than 6 months. HP carries a 50-70-fold increased risk of pancreatic cancer within 7-30 years of disease onset. HP diagnosis is defined by the presence of a detected cationic trypsinogen gene mutation (with or without clinical or radiological manifestations of chronic pancreatitis) or when the patient's family satisfies the requirements of the EUROPAC.

TREATMENT

With regard to the therapeutic approach, pancreatic enzyme replacement therapy and analgesics are offered to control pain. In addition, endoscopic and surgical intersections are reserved for all relevant complications. Unfortunately, surgical removal of affected pancreatic tissue does not necessarily guarantee the patient's long-term survival. Furthermore, the prognostic factors and the efficacy of extended resection remain controversial.

Further characterization of HDAC and SIRT gene expression patterns in pancreatic cancer and their relation to disease outcome

Ductal adenocarcinoma of the pancreas is ranking 4 for patient' death from malignant disease in Western countries, with no satisfactory treatment. We re-examined more precisely the histone deacetylases (HDAC) and Sirtuin (SIRT) gene expression patterns in pancreatic cancer with more pancreatic tumors and normal tissues. We also examined the possible relationship between HDAC gene expression levels and long term disease outcome. Moreover, we have evaluated by using an in vitro model system of human pancreatic tumor cell line whether HDAC7 knockdown may affect the cell behavior. We analyzed 29 pancreatic adenocarcinoma (PA), 9 chronic pancreatitis (CP), 8 benign pancreatic (BP) and 11 normal pancreatic tissues. Concerning pancreatic adenocarcinoma, we were able to collect biopsies at the tumor periphery. To assess the possible involvement of HDAC7 in cell proliferation capacity, we have generated recombinant human Panc-1 tumor which underexpressed or overexpressed HDAC7. The expression of HDAC1,2,3,4,7 and Nur77 increased in PA samples at levels significantly higher than those observed in the CP group (p = 0.0160; 0.0114; 0.0227; 0.0440; 0.0136; 0.0004, respectively). The expression of HDAC7, was significantly greater in the PA compared with BP tissue samples (p = 0.05). Mean mRNA transcription levels of PA for HDAC7 and HDAC2 were higher when compared to their counterpart biopsies taken at the tumor periphery (p = 0.0346, 0.0053, respectively). Moreover, the data obtained using confocal microscopy and a quantitative method of immunofluorescence staining strongly support the HDAC7 overexpression in PA surgical specimens. The number of deaths and recurrences at the end of follow up were significantly greater in patients with overexpression of HDAC7. Interestingly, the rate of growth was significantly reduced in the case of cell carrying shRNA construct targeting HDAC7 encoding gene when compared to the parental Panc-1 tumor cells (p = 0.0015) at 48 h and 96 h (p = 0.0021). This study strongly support the notion that HDAC7play a role in pancreatic adenocarcinoma progression.

PRSS1 and SPINK1 mutations in idiopathic chronic and recurrent acute pancreatitis

AIM: To identify gene mutations in PRSS1 and SPINK1 in individuals with early onset idiopathic chronic or recurrent acute pancreatitis.

METHODS: The cationic trypsinogen gene (PRSS1; exons 2 and 3) and the serine protease inhibitor Kazal 1 gene (SPINK1; exon 3) were selectively amplified and sequenced from blood samples of 19 patients admitted to the Pancreas Clinic at our institution with chronic pancreatitis and/or idiopathic recurrent acute pancreatitis that were diagnosed or with onset before age 35. Fifty healthy volunteers served as controls. Whole blood samples were collected and gene specific sequences were amplified by polymerase chain reaction (PCR). All PCR products were subsequently sequenced in order to identify the presence of any mutations.

RESULTS: Nineteen patients with pancreatitis (14 males; median age 24 years, range 15-48 years) were included in this study, of which five showed the presence of gene mutations. Direct sequencing results indicated the presence of two previously unidentified mutations in exon 2 of PRSS1 (V39E and N42S) in two patients with recurrent acute pancreatitis. Two cases had the N34S SPINK1 mutation. Analysis of the relatives of one patient homozygous for this mutation showed that five of the six family members carried the N34S SPINK1 mutation. Of these members, three were healthy heterozygous carriers and two were homozygotes (one sibling had diabetes, the other was healthy). Another patient was heterozygous for a novel SPINK1 mutation located on exon 3 (V46D). All members from this patient’s family had normal genotypes, indicating that it was a de novo mutation. No mutations in either gene were present in the control subjects.

CONCLUSION: Two novel PRSS1 mutations and one novel SPINK1 mutation were identified in Mexican patients with early onset idiopathic recurrent acute pancreatitis.

Serum cytokine biomarker panels for discriminating pancreatic cancer from benign pancreatic disease

BACKGROUND

We investigated whether combinations of serum cytokines, used with logistic disease predictor models, could facilitate the detection of pancreatic ductal adenocarcinoma (PDAC).

METHODS

The serum levels of 27 cytokines were measured in 241 subjects, 127 with PDAC, 49 with chronic pancreatitis, 20 with benign biliary obstruction and 45 healthy controls. Samples were split randomly into independent training and test sets. Cytokine biomarker panels were selected by identifying the top performing cytokines in best fit logistic regression models during multiple rounds of resampling from the training dataset. Disease prediction by logistic models, built using the resulting cytokine panels, was evaluated with training and test sets and further examined using resampled performance evaluation.

RESULTS

For the discrimination of PDAC patients from patients with benign disease, a panel of IP-10, IL-6, PDGF plus CA19-9 offered improved diagnostic performance over CA19-9 alone in the training (AUC 0.838 vs. 0.678) and independent test set (AUC 0.884 vs. 0.798). For the discrimination of PDAC from CP, a panel of IL-8, CA19-9, IL-6 and IP-10 offered improved diagnostic performance over CA19-9 alone with the training (AUC 0.880 vs. 0.758) and test set (AUC 0.912 vs. 0.848). Finally, for the discrimination of PDAC in the presence of jaundice from benign controls with jaundice, a panel of IP-10, IL-8, IL-1b and PDGF demonstrated improvement over CA19-9 in the training (AUC 0.810 vs. 0.614) and test set (AUC 0.857 vs. 0.659).

CONCLUSIONS

These findings support the potential role for cytokine panels in the discrimination of PDAC from patients with benign pancreatic diseases and warrant additional study.

Regulation of pancreatic inflammation by connective tissue growth factor (CTGF/CCN2)

Pancreatitis is caused by long-term heavy alcohol consumption, which results in injury and death of pancreatic acinar cells (PAC). The PAC play a pivotal role in mediating early inflammatory responses but the underlying mechanisms remain poorly understood. Treatment of C57BL/6 mice with ethanol and cerulein resulted in increased staining for acinar interleukin- 1b (IL-1b), chemokine (C-C motif) ligand 3 (CCL3), or connective tissue growth factor (CTGF/CCN2) by Day 16 and this was associated with increased infiltration of F4/80-positive macrophages and increased expression of pancreatic CTGF/CCN2 mRNA. Compared with wild-type Swiss Webster mice, ethanol treatment of pan-green fluorescent protein (GFP)-CTGF/CCN2 transgenic mice caused enhanced acinar staining for GFP or CTGF/CCN2 and a significant increase in pancreatic infiltration of F4/80-positive macrophages or NIMP-R14-positive neutrophils. Treatment of primary mouse PAC or the rat AR42J PAC line with ethanol or CTGF/CCN2 resulted in enhanced expression of IL-1b or CCL3. Conditioned medium from CTGF/CCN2-treated AR42J cells induced chemotaxis in NR8383 macrophages and this response was abrogated in a dose dependent manner by addition of BX471, an inhibitor of chemokine (C-C motif) receptor 1. These results reveal that acinar CTGF/CCN2 plays a novel role in alcohol-induced inflammatory processes in the pancreas by increasing infiltration of macrophages and neutrophils and increasing acinar production of inflammatory mediators such as IL-1b or CCL3. The early production of CTGF/CCN2 by PAC to drive inflammation is distinct from its previously reported production by pancreatic stellate cells to drive fibrosis at later stages of pancreatic injury.

Sonic hedgehog expression in a rat model of chronic pancreatitis

AIM: To analyze the activation of sonic hedgehog (SHh) signaling pathways in a rat model of chronic pancreatitis.

METHODS: Forty Wistar rats were randomly divided into 2 groups: experimental group and control group (20 rats in each group). Dibutyltin dichloride was infused into the tail vein of the rats to induce chronic pancreatitis in the experimental group. The same volume of ethanol and glycerol mixture was infused in the control group. The expression of Ptch, Smo and Gli were analyzed using immunohistochemistry, and real-time reverse transcription polymerase chain reaction (RT-PCR).

RESULTS: Compared with the control group, significant histological changes in terms of the areas of abnormal architecture, glandular atrophy, fibrosis, pseudo tubular complexes, and edema were observed at week 4 in the experimental group. The expression of Ptch1, Smo and Gli1 in the pancreatic tissue increased significantly in the experimental group. Using RT-PCR, mRNA levels of Ptch, Smo and Gli in the experimental group increased significantly compared with the control group.

CONCLUSION: The SHh signaling pathway is aberrantly activated in rats with chronic pancreatitis. The SHh signaling pathway plays an important role in the development of chronic pancreatitis. These results may be helpful in studies focusing on the relationship between chronic pancreatitis and pancreatic cancer.

Functional effects of 13 rare PRSS1 variants presumed to cause chronic pancreatitis

OBJECTIVE

Hereditary pancreatitis is caused by mutations in human cationic trypsinogen (PRSS1) which lead to increased autoactivation by altering chymotrypsin C (CTRC)-dependent trypsinogen activation and degradation. Exceptions are some cysteine mutations which cause misfolding, intracellular retention and endoplasmic reticulum stress. Clinical relevance of many PRSS1 variants found in patients with sporadic chronic pancreatitis is unknown but often assumed by analogy with known disease-causing mutations. Functional comparison of PRSS1 variants found in sporadic and hereditary cases is needed to resolve this dilemma.

DESIGN

Here, we investigated the functional phenotype of 13 published PRSS1 variants with respect to autoactivation in the presence of CTRC and cellular secretion.

RESULTS

Only mutation p.D100H increased trypsinogen autoactivation, but this gain in function was offset by a marked reduction in secretion. Five mutants (p.P36R, p.G83E, p.I88N, p.V123M, p.S124F) showed decreased autoactivation due to increased degradation by CTRC. Five mutants exhibited strongly (p.D100H, p.C139F) or moderately (p.K92N, p.S124F, p.G208A) reduced secretion, whereas mutant p.K170E showed slightly increased secretion. Mutant p.I88N was also secreted to higher levels but was rapidly degraded by CTRC. Finally, three mutants (p.Q98K, p.T137M, p.S181G) had no phenotypic alterations relative to wild-type trypsinogen.

CONCLUSIONS

Rare PRSS1 variants found in sporadic chronic pancreatitis do not stimulate autoactivation but may cause increased degradation, impaired secretion or no functional change. Variants with reduced secretion are likely pathogenic due to mutation-induced misfolding and consequent endoplasmic reticulum stress.

Utilization of CDX2 expression in diagnosing pancreatic ductal adenocarcinoma and predicting prognosis

CDX2, a master transcriptional regulator of intestinal cell differentiation and survival, has been used as a marker to indicate colorectal lineage in adenocarcinomas of unknown origin. Pancreatic ductal adenocarcinoma (PDAC) is one of the most common causes for adenocarcinomas of unknown origin, but CDX2 expression in pancreatic disease remains unclear. In this study, we systemically and extensively investigated the expression and role of CDX2 in PDAC. We reported that CDX2 expression is weak and heterogeneous is all normal pancreas and chronic pancreatitis. It is largely expressed in epithelial-lining cells of pancreatic ducts including main ducts, inter-lobular ducts, intra-lobular ducts, intercalated ducts and centroacinar cells, but not in acinar cells or islet cells. CDX2 expression is down regulated during the transformation process from PanIN to PDAC. Only one third of PDACs retain some degree of CDX2 expression, and this group of PDACs have reduced median survival time compared to that of CDX2 negative group (308 days vs. 586 days, p = 0.0065). Metastatic PDACs remain similar expression pattern to that of the primary sites. Our study clearly demonstrates CDX2 expression in pancreatic diseases including PDAC, which is practically important when CDX2 is used to establish the primary sites of adenocarcinomas of unknown origin. In addition, our study also provides CDX2 as a prognostic marker for PDAC and implicates an important role of CDX2 in the development of normal pancreas and PDAC.

Familial pancreatic cancer: genetic advances

Beset by poor prognosis, pancreatic ductal adenocarcinoma is classified as familial or sporadic. This review elaborates on the known genetic syndromes that underlie familial pancreatic cancer, where there are opportunities for genetic counseling and testing as well as clinical monitoring of at-risk patients. Such subsets of familial pancreatic cancer involve germline cationic trypsinogen or PRSS1 mutations (hereditary pancreatitis), BRCA2 mutations (usually in association with hereditary breast-ovarian cancer syndrome), CDKN2 mutations (familial atypical mole and multiple melanoma), or DNA repair gene mutations (e.g., ATM and PALB2, apart from those in BRCA2). However, the vast majority of familial pancreatic cancer cases have yet to have their genetic underpinnings elucidated, waiting in part for the results of deep sequencing efforts.

Oligonucleotide microarray identifies genes differentially expressed during tumorigenesis of DMBA-induced pancreatic cancer in rats

The extremely dismal prognosis of pancreatic cancer (PC) is attributed, at least in part, to lack of early diagnosis. Therefore, identifying differentially expressed genes in multiple steps of tumorigenesis of PC is of great interest. In the present study, a 7,12-dimethylbenzanthraene (DMBA)-induced PC model was established in male Sprague-Dawley rats. The gene expression profile was screened using an oligonucleotide microarray, followed by real-time quantitative polymerase chain reaction (qRT-PCR) and immunohistochemical staining validation. A total of 661 differentially expressed genes were identified in stages of pancreatic carcinogenesis. According to GO classification, these genes were involved in multiple molecular pathways. Using two-way hierarchical clustering analysis, normal pancreas, acute and chronic pancreatitis, PanIN, early and advanced pancreatic cancer were completely discriminated. Furthermore, 11 upregulated and 142 downregulated genes (probes) were found by Mann-Kendall trend Monotone test, indicating homologous genes of rat and human. The qRT-PCR and immunohistochemistry analysis of CXCR7 and UBe2c, two of the identified genes, confirmed the microarray results. In human PC cell lines, knockdown of CXCR7 resulted in decreased migration and invasion. Collectively, our data identified several promising markers and therapeutic targets of PC based on a comprehensive screening and systemic validation.

Mutational analysis of ATP8B1 in patients with chronic pancreatitis

Background

Mutations in genes encoding cationic trypsinogen (PRSS1), pancreatic secretory trypsin inhibitor (SPINK1) and chymotrypsinogen C (CTRC) are associated with chronic pancreatitis. However, in many patients with a familial chronic pancreatitis pattern suggesting a genetic cause, no mutations in either of these genes can be found, indicating that other, still unknown, associated genes exist. In this respect ATP8B1 is an interesting candidate due to its strong expression in the pancreas, its supposed general function in membrane organization and the higher incidence of pancreatitis in patients with ATP8B1 deficiency.

Methods

We analyzed all 27 ATP8B1 coding exons and adjacent non-coding sequences of 507 chronic pancreatitis patients by direct sequencing. Exons that harbored possible relevant variations were subsequently sequenced in 1,027 healthy controls.

Results

In the exonic regions, 5 novel non-synonymous alterations were detected as well as 14 previously described alterations of which some were associated with ATP8B1 deficiency. However, allele frequencies for any of these variations did not significantly differ between patients and controls. Furthermore, several non-synonymous variants were exclusively detected in control subjects and multiple variants in the non-coding sequence were identified with similar frequencies in both groups.

Conclusions

We did not find an association between heterozygous ATP8B1 variants and chronic pancreatitis in our cohort of patients with hereditary and idiopathic chronic pancreatitis.

Analysis of serum exosomal microRNAs and clinicopathologic features of patients with pancreatic adenocarcinoma

BACKGROUND

Altered expression of serum microRNAs (miRNAs) have been reported to correlate with carcinogenesis and progression of pancreatic adenocarcinoma (PC), but descriptions of serum exosomal miRNAs in PC are still lacking. This study was designed to evaluate serum exosomal miRNA levels in PC patients and to investigate their relationships with clinicopathologic features and prognosis.

METHODS

Four miRNAs (miR-17-5p, miR-21, miR-155 and miR-196a) related to PC were selected for examination in our research. Serum miRNA was examined by RT-PCR in a group of 49 patients, including 22 with PCs, 6 with benign pancreatic tumors, 7 with ampullary carcinomas, 6 with chronic pancreatitis and 8 healthy participants. The clinicopathologic data were also collected, and PC patients were classified according to the presence of metastasis, tumor differentiation and advanced stage.

RESULTS

There were low expressions of exosomal miR-155 and miR-196a in serum samples of PC patients when U-6 was used as a control. Serum exosomal miR-17-5p was higher in PC patients than in non-PC patients and healthy participants. High levels of miR-17-5p were significantly correlated with metastasis and advanced stage of PC. The serum exosomal miR-21 level in PC was higher than that in the normal and chronic pancreatitis groups, but was not significantly correlated with PC differentiation and tumor stage.

CONCLUSIONS

There were high expressions of serum exosomal miR-17-5p and miR-21 in PC patients. Examination of serum exosomal microRNA is a useful serum biomarker for PC diagnosis other than serum-free microRNA. It is postulated that exosomal miR-17-5p participates in the progression of PC.

A conservative assessment of the major genetic causes of idiopathic chronic pancreatitis: data from a comprehensive analysis of PRSS1, SPINK1, CTRC and CFTR genes in 253 young French patients

Idiopathic chronic pancreatitis (ICP) has traditionally been defined as chronic pancreatitis in the absence of any obvious precipitating factors (e.g. alcohol abuse) and family history of the disease. Studies over the past 15 years have revealed that ICP has a highly complex genetic architecture involving multiple gene loci. Here, we have attempted to provide a conservative assessment of the major genetic causes of ICP in a sample of 253 young French ICP patients. For the first time, conventional types of mutation (comprising coding sequence variants and variants at intron/exon boundaries) and gross genomic rearrangements were screened for in all four major pancreatitis genes, PRSS1, SPINK1, CTRC and CFTR. For the purposes of the study, synonymous, intronic and 5'- or 3'-untranslated region variants were excluded from the analysis except where there was persuasive evidence of functional consequences. The remaining sequence variants/genotypes were classified into causative, contributory or neutral categories by consideration of (i) their allele frequencies in patient and normal control populations, (ii) their presumed or experimentally confirmed functional effects, (iii) the relative importance of their associated genes in the pathogenesis of chronic pancreatitis and (iv) gene-gene interactions wherever applicable. Adoption of this strategy allowed us to assess the pathogenic relevance of specific variants/genotypes to their respective carriers to an unprecedented degree. The genetic cause of ICP could be assigned in 23.7% of individuals in the study group. A strong genetic susceptibility factor was also present in an additional 24.5% of cases. Taken together, up to 48.2% of the studied ICP patients were found to display evidence of a genetic basis for their pancreatitis. Whereas these particular proportions may not be extrapolable to all ICP patients, the approach employed should serve as a useful framework for acquiring a better understanding of the role of genetic factors in causing this oligogenic disease.

Characterization of two deletions of the CTRC locus

Novel variants associated with chronic pancreatitis are being increasingly reported. However, most studies have so far only analyzed point mutations and small insertions or deletions. Here we report the characterization of two distinct deletions of the CTRC locus. Variants in four chronic pancreatitis genes, PRSS1, SPINK1, CTRC and CFTR, were systematically analyzed in the studied cases. Copy number change of the CTRC gene was analyzed by quantitative fluorescent multiplex PCR (QFM-PCR). Walking QFM-PCR followed by long-range PCR and direct sequencing were employed to identify the deletion breakpoints at the nucleotide level. A heterozygous CTRC-deleting complex rearrangement, which was co-inherited with different trans variants in SPINK1, CFTR or PRSS1, is associated with variable phenotypes (chronic pancreatitis; pancreatic cancer and chronic pancreatitis; and type 1 diabetes). Moreover, a different homozygous deletion of the CTRC locus was found in an unrelated patient with asymptomatic chronic pancreatitis. Our findings revealed a hitherto unrecognized level of complexity of genotype-phenotype correlation in chronic pancreatitis. The CTRC-deleting complex rearrangement probably resulted from LINE-1-mediated Alu insertion, which represents a novel mutational mechanism causing chronic pancreatitis.

PRSS1_p.Leu81Met mutation results in autoimmune pancreatitis

AIM: To describe protease serine 1 (PRSS1) gene mutations in patients with autoimmune pancreatitis (AIP) and the clinical features of AIP.

METHODS: Fourteen patients with AIP, 56 with other chronic pancreatitis, 254 with pancreatic cancer and 120 normal controls were studied. The mutations and polymorphisms of four genes involved with pancreatitis or pancreatic cancer, PRSS1, SPINK1, CFTR and MEN1, were sequenced. The pathogenic mechanism of AIP was investigated by comparing the wild-type expression system with the p.81Leu→Met mutant expression system.

RESULTS: Two novel mutations (p.81Leu→Met and p.91Ala→Ala) were found in PRSS1 gene from four patients with AIP. PRSS1_p.81Leu→Met mutation led to a trypsin display reduction (76.2%) combined with phenyl agarose (Ca²⁺ induced failure). Moreover, the ratio of trypsin/amylase in patients with AIP was higher than in the patients with pancreatic cancer and other pancreatitis. A large number of lymphocytes and plasma cells were found in the bile ducts accompanied by hyperplasia of myofibroblasts.

CONCLUSION: Autoimmune pancreatitis may be related to PRSS1 gene mutations.

Low penetrance pancreatitis phenotype in a Venezuelan kindred with a PRSS1 R122H mutation

CONTEXT

Hereditary pancreatitis is typically caused by the PRSS1 R122H or N29I mutations resulting in high penetrance (about 80%) autosomal dominant disorder that is usually reported in North America, Northern Europe and Northeast Asia, but not South America, Africa or India.

CASE REPORT

Here we report a kindred from Venezuela, South America with the PRSS1 R122H variant. Only the proband, an 11-year old boy with severe chronic pancreatitis, and a maternal grandmother with pancreatitis at age 60 years (confirmed PRSS1 R122H), are symptomatic.

CONCLUSIONS

Issues of mutation prevalence, non-penetrance, and disease recognition in various countries are discussed.

Familial gastric and pancreatic cancers: Diagnosis and screening

Screening for gastric and pancreatic cancers in asymptomatic individuals is not routinely practiced in the United States. While there is insufficient evidence that general population screening would reduce morbidity and/or mortality associated with these cancers, the utility of screening for individuals at increased risk warrants further study. Clinical challenges include identifying high risk individuals who would be most likely to benefit from screening and determining which screening modalities and intervals would be most effective.

Association of 5, 10- methylenetetrahydrofolate reductase C677T polymorphism in susceptibility to tropical chronic pancreatitis in north Indian population

MTHFR is a key enzyme in folate metabolism that catalyzes the conversion of 5, 10&mdash;methlenetetrahydrofolate (5, 10&mdash; methylene THF) to 5&mdash;methyltetrahydrofolate (5&mdash;methyl THF), a predominant circulatory form of folate and methyl donor for the remethylation of homocysteine to methionine. Some studies have shown that C667T polymorphism increases the risk of pancreatic cancer. Since MTHFR is involved in methylation, inflammation and protection against oxidative stress, the processes especially important for pancreatic homeostasis. The altered enzyme activity could play a role in pancreatic injury. The role of MTHFR C677T polymorphism in chronic pancreatitis has been explored by conducting a hospital based; case&mdash;control study involving 100 patients radiologically confirmed chronic pancreatitis and 329 healthy controls. All samples were analyzed for MTHFR C677T polymorphism using PCR&mdash;RFLP method. Restriction enzyme Hinf I was used to digest the 198 bp amplified product. The frequency of the MTHFR was 57.3%, 34.1% and 8.5% among cases compared with 87.2%,11.2% and 1.5% of controls for CC, CT and TT genotypes, respectively. The T Allele frequency was found significantly higher in patients than in controls. A significant association with T allele was observed with p&mdash;value (&lt; 0.0001) odds ratio 4.475 and (95% CI=2.961&mdash;7.046). It could be predisposing to the traditional risk factors such as diabetes, dietary, alcohal and smoking habit that are known to be associated with chronic pancreatitis. Additionally it was observed that smoking increases the risk of chronic pancreatitis by 4.1 times. The T allele frequency of MTHFR (C667T) was found to be a significant risk factor for chronic pancreatitis playing a crucial role in altered folate metabolsim.

The number of tandem repeats in the carboxyl-ester lipase (CEL) gene as a risk factor in alcoholic and idiopathic chronic pancreatitis

BACKGROUND/AIMS

The variable number of tandem repeats (VNTR) in the last exon of the carboxyl-ester lipase (CEL) gene has been reported to associate with alcohol-induced chronic pancreatitis (ACP) in a Japanese study. Here, we have investigated the association between the number of CEL VNTR repeats and ACP or idiopathic chronic pancreatitis (ICP) in a cohort of German patients.

METHODS

Patients diagnosed with ACP (n = 203) or ICP (n = 64) were genotyped using a screening method consisting of PCR followed by DNA fragment analysis. The allele frequencies of different CEL VNTR lengths were compared to the frequencies in healthy controls (n = 390).

RESULTS

We observed no statistical significant associations between CEL VNTR allele frequencies and ACP or ICP.

CONCLUSION

This study did not find evidence that supported an association between the common length variations of the CEL VNTR and chronic pancreatitis.

Bull's-eye pattern of pancreatic-duct stones on multidetector computed tomography and gene-mutation-associated pancreatitis (GMAP)

PURPOSE

This study prospectively assessed whether the presence of a bull's-eye pattern of pancreatic-duct stones on multidetector computed tomography (MDCT) correlated with gene-mutation-associated pancreatitis (GMAP) and whether other signs suggestive of GMAP can be detected with MDCT.

MATERIALS AND METHODS

Forty-seven patients with chronic calcific pancreatitis underwent genetic testing for CFTR, SPINK1 and PRSS1 mutations and an MDCT scan of the abdomen. Qualitative analysis assessed the presence or absence of pancreatic-duct stones with bull's-eye appearance. Quantitative analysis included the number and maximum diameter of stones and the diameter of the main pancreatic duct.

RESULTS

Fifteen of 47 patients (32%) were positive for gene mutations (GMAP patients). The bull's-eye pattern was found in 10/15 patients (67%) with GMAP and in 4/32 (12%) patients with chronic pancreatitis not associated with GMAP (NGMAP; p<0.0001). The mean diameter of duct stones was 15 mm in patients with GMAP and 10 mm in patients with NGMAP (p<0.04).

CONCLUSIONS

The presence of duct stones with a bull's-eye pattern correlates with GMAP. Duct stones with diameter ≥15 mm are another sign suggestive of GMAP.

p38MAPK suppresses chronic pancreatitis by regulating HSP27 and BAD expression

Mitogen-activated protein kinases (MAPKs) are ubiquitous proteins that function in both normal and stress-related pathophysiological states of the cell. This study aimed to analyze the importance of p38MAPK in pancreatic injury using WBN/Kob rats with spontaneous chronic pancreatitis. Male WBN/Kob rats were injected with the p38MAPK inhibitor SB203580, starting at the age of 4 weeks, and sacrificed 6 weeks later. Compared with vehicle-treated rats, p38 inhibitor-treated rats exhibited a significant increase in pancreatic cell death and inflammation as assessed by histologic examination and myeloperoxidase activity, respectively. p38 inhibition decreased the expression of heat shock protein 27 (HSP27), an antioxidant protein, and enhanced accumulation of reactive oxygen species (ROS). In addition, the proapoptotic protein BAD was increased in the pancreas of rats treated with p38 inhibitor. In a pancreatic cell line (PANC-1), HSP27 knockdown augmented reactive oxygen species accumulation and cell death induced by tumor necrosis factor-α plus actinomycin D. In conclusion, p38MAPK suppresses chronic pancreatitis by upregulating HSP27 expression and downregulating BAD expression.

Clinical impact of K-ras mutation analysis in EUS-guided FNA specimens from pancreatic masses

BACKGROUND

EUS-guided FNA (EUS-FNA) is considered optimal for differentially diagnosing pancreatic masses. However, the sensitivity of EUS-FNA ranges from 65% to 95%, respectively, which requires improvement.

OBJECTIVE

To evaluate clinical impact of K-ras mutation analysis in EUS-FNA specimens from pancreatic masses.

DESIGN

Prospective registration, single-center study.

SETTING

Tertiary referral center.

PATIENTS

This study involved 394 consecutive patients with pancreatic masses (307 pancreatic ductal adenocarcinomas [PDACs], 47 pancreatic inflammatory lesions, and 40 other types of tumors) who underwent EUS-FNA and analysis of K-ras mutations.

INTERVENTION

EUS-FNA, Cycleave polymerase chain reaction.

MAIN OUTCOME MEASUREMENTS

Improvement of the diagnostic accuracy by K-ras mutation analysis; absence of K-ras mutations in non-PDAC masses.

RESULTS

K-ras mutations were detected in 266 of 307 PDAC aspirates (87%) and in 3 of 87 non-PDAC masses (3%). K-ras mutations were detected in 18 of 39 patients (46%) who remained cytohistopathologically undiagnosed. The sensitivity, specificity, positive and negative predictive values, and accuracy of cytohistopathological and K-ras mutation analyses alone were 87%, 100%, 100%, 54%, and 89%, respectively, and, when combined, were 93%, 100%, 100%, 68%, and 94%, respectively. Adding K-ras mutation analysis to standard cytohistopathological assessment increased the sensitivity and accuracy of EUS-FNA by 6% (P < .001) and 5% (P < .001), respectively.

LIMITATIONS

Single-center study.

CONCLUSIONS

K-ras mutation analysis may be helpful in patients with suspected PDAC yet inconclusive EUS-FNA findings. K-ras mutations were extremely rare in pancreatic inflammation and other pancreatic tumors.

Chronic pancreatitis

PURPOSE OF REVIEW

We review important new clinical observations in chronic pancreatitis made in the past year.

RECENT FINDINGS

Tropical pancreatitis associates with SPINK1 and/or CFTR gene mutations in approximately 50% of patients, similar to the frequency in idiopathic chronic pancreatitis. Corticosteroids increase secretin-stimulated pancreatic bicarbonate concentrations in autoimmune pancreatitis (AIP) by restoring mislocalized CFTR protein to the apical ductal membrane. Most patients with asymptomatic hyperenzymemia have pancreatic lesions of unclear significance or no pancreatic lesions. Common pitfalls in the use of diagnostic tests for exocrine pancreatic insufficiency (EPI) confound interpretation of findings in irritable bowel syndrome and severe renal insufficiency. Further study is needed to improve the accuracy of endoscopic ultrasonography (EUS) to diagnose chronic pancreatitis. Celiac plexus block provides short-term pain relief in a subset of patients.

SUMMARY

Results of this year's investigations further elucidated the genetic associations of tropical pancreatitis, a reversible mislocalization of ductal CFTR in AIP, the association of asymptomatic pancreatic hyperenzymemia with pancreatic disorders, limitations of diagnostic tests for EPI, diagnosis of chronic pancreatitis by EUS and endoscopic pancreatic function testing and treatment of pain.

Catechol-O-methyltransferase (COMT) gene variants and pain in chronic pancreatitis

BACKGROUND

Pain is the major symptom of chronic pancreatitis. The role of genetics in pancreatic pain is unclear. Catechol-O-methyltransferase (COMT) regulates enkephalin levels and influences pain perception. The COMT gene contains functional polymorphisms that have been found to influence human pain perception. The aim of our study was to investigate COMT single-nucleotide polymorphisms (SNP s) and diplotypes in chronic pancreatitis patients and healthy controls.

METHODS

We genotyped four COMT gene SNP s: c.1-98A>G (rs6269), c.186C>T (p.=) (rs4633), c.408C>G (p.=) (rs4818) and c.472G>A (p.Val158Met) (rs4680) using a dual-colour discrimination assay in 240 chronic pancreatitis patients and 445 controls. We generated five diplotypes with a frequency >0.5% and compared prevalence between patients and controls.

RESULTS

There was no significant association between the SNPs in the COMT gene and chronic pancreatitis. The diplotype ATCA÷ACCG was more prevalent in controls compared with patients (OR 0.48, 95% CI 0.24 to 0.93, p=0.03) where the most common diplotype GCGG ÷ATCA served as reference. However, after correction for multiple testing, this is not a significant difference. The distribution of other diplotypes was not significantly different between patients and controls.

CONCLUSION

COMT SNP s and diplotypes are not associated with chronic pancreatitis. As a consequence, our results do not support a significant role for the COMT gene in chronic pancreatitis.

Common CFTR haplotypes and susceptibility to chronic pancreatitis and congenital bilateral absence of the vas deferens

CFTR mutations enhance susceptibility for idiopathic chronic pancreatitis (ICP) and congenital bilateral absence of the vas deferens (CBAVD); however, it is unknown why CFTR heterozygotes are at increased disease risk. We recently showed that common CFTR variants are associated with aberrantly spliced transcripts. Here, we genotyped for common CFTR variants and tested for associations in two ICP (ICP-A: 126 patients, 319 controls; ICP-B: 666 patients, 1,181 controls) and a CBAVD population (305 patients, 319 controls). Haplotype H10 (TG11-T7-470V) conferred protection (ICP-A: OR 0.19, P<0.0001; ICP-B: OR 0.78, P = 0.06; CBAVD OR 0.08, P<0.001), whereas haplotype H3 (TG10-T7-470M) increased disease risk (ICP-A: OR 8.34, P = 0.003; ICP-B: OR 1.88, P = 0.007; CBAVD: OR 5.67, P = 0.01). The risk of heterozygous CFTR mutations carriers for ICP (OR 2.44, P<0.001) and CBAVD (OR 14.73, P<0.001) was fully abrogated by the H10/H10 genotype. Similarly, ICP risk of heterozygous p.Asn34Ser SPINK1 mutation carriers (OR 10.34, P<0.001) was compensated by H10/H10. Thus, common CFTR haplotypes modulate ICP and CBAVD susceptibility alone and in heterozygous CFTR and p.Asn34Ser mutation carriers. Determination of these haplotypes helps to stratify carriers into high- and low-risk subjects, providing helpful information for genetic counseling.

[Strategies for screening for pancreatic adenocarcinoma in high-risk patients: the place of endoscopic ultrasound]

Screening high-risk individuals with imaging tests, such endoscopic ultrasound and computed tomography, can lead to the detection and treatment of predominantly asymptomatic premalignant lesions. These pancreatic lesions consist of resectable, mostly branch-type non invasive intraductal papillary mucinous neoplasms. Endoscopic ultrasound features of chronic pancreatitis are highly prevalent in high-risk individuals and these directly correlate with multifocal lobulocentric parenchymal atrophy due to pancreatic intraepithelial neoplasia. Long-term, multi-prospective studies are needed to determine if screening for early pancreatic adenocarcinoma and timely intervention results in decreased pancreatic cancer incidence and mortality in high-risk individuals.

[Effect of pancreatic secretory trypsin gene mutations on the development of chronic pancreatitis]

For the first time the relationship between mutations in the pancreatic secretory trypsin inhibitor (SPINK1) in humans and the development of chronic pancreatitis was established in 2000. By mid 2011 the number of studies on the influence of SPINK1 gene mutations on the development of pancreatitis exceeds 250, the results vary greatly. According to modern concepts, mutations in SPINK1 gene are associated with the development of both acute and chronic pancreatitis, and are defined in all etiological forms. Literature review shows the data of the most significant studies about the role of SPINK1 gene mutations in pancreatic diseases.

[Pancreatic secretory trypsin inhibitor gene N34S mutation in patients with idiopathic chronic pancreatitis]

PURPOSE

To determine the frequency and prognostic significance of mutation N34S in the development of CP in a mixed Russian population.

METHODS

The study included 83 patients with idiopathic CP and 103 healthy individuals. The diagnosis of CP was based on clinical and instrumental data in accordance with the criteria of M-ANNHEIM. Everyone involved in this study using PCR followed by restriction analysis performed the N34S mutation analysis in the gene for the ICU.

RESULTS

N34S mutation was detected in 12 patients with CP and in 3 of the control group, which accounted for 14.6 and 2.9% respectively; p<0,05. The odds ratio (OR) of idiopathic CP in the presence of mutation N34S was 4.62 (95% confidence interval (CI): 1,21-18,37). The difference in frequency of homozygotes the mutant allele was statistically significant: 10.97 and 0.97% in the main and control groups, respectively; p<0,05. The presence of mutations did not affect the frequency and severity of functional disorders of the pancreas, but the mutation N34S was statistically significantly more common in patients with calcifying pancreatitis (p<0,01) and the presence of pseudocysts (p<0,05). OR the development of calcification in patients with the presence of N345 was 13.44 (95% CI: 6,29-23,78).

CONCLUSION

These data suggest that the mutation N34S plays a significant role in the development of CP in the Russian population and can detect more than 10% of cases of idiopathic CP.

Some aspects of the etiology and the pathogenesis of chronic pancreatitis

The development of modern technology and advances in medical science make possible understanding of etiology of chronic pancreatitis. From a century ago, the ethanol is connected to chronic pancreatitis. In the last decades medical science made a big footstep in understanding of so called "idiopathic pancreatitis". Factors as autoimmune disturbances, toxins, gene mutations, geographic characteristics are already known as cornerstones in etiology and pathogenesis of the disease.

Vascular endothelial growth factor (VEGF) genotype and serum concentration in patients with pancreatic adenocarcinoma and chronic pancreatitis

Vascular endothelial growth factor (VEGF) is necessary for microvasculature development and important for growth and spread of pancreatic tumors. Functional polymorphism of VEGF gene at position C-460T and G+405C may influence VEGF serum level. VEGF gene polymorphisms at position C-460T and G+405C were evaluated in 85 patients with pancreatic adenocarcinoma (PA), 72 - with chronic pancreatitis (CP) and 50 healthy volunteers. VEGF genotypes were studied in DNA isolated from blood samples and serum VEGF concentrations were measured. We found an increased frequency of the homozygous +405C/C VEGF genotype in patients with PA (55.3%) compared with CP (25%) and control group (16%; p<0.01). In contrast, the distribution of genotype and allele frequencies of the -460C/T polymorphism in the PA patients did not differ from those in CP and control groups. Serum levels of VEGF were significantly higher in PA patients (mean level: 441 ± 37.2 pg/ml) compared with CP patients (217 ± 13.6 pg/ml; p<0.001) and control group (137 ± 7.7 pg/ml; p<0.001). No relationship between VEGF serum levels and VEGF gene polymorphisms have been found. Our findings suggest that +405C/C VEGF genotype may contribute to pancreatic carcinogenesis. VEGF serum levels, although elevated in PA patients, are not associated with analysed VEGF polymorphisms.

Total pancreatectomy and islet cell autotransplantation as a means of treating patients with genetically linked pancreatitis

BACKGROUND

For patients with severe chronic pancreatitis, total or completion pancreatectomy with islet cell autotransplantation (IAT) can alleviate pain and avoid the complications of diabetes. Several genetic mutations, specifically, PRSS1, CFTR, and SPINK1, are associated with chronic pancreatitis. Few reports have focused on the benefit of this operation for this subset of patients.

METHODS

Between February 2000 and July 2009, 118 patients were treated with total pancreatectomy and IAT for chronic pancreatitis. Patients with known genetic mutations were then selected for further analysis.

RESULTS

Of the 188 patients, 16 (13.6%) patients were identified as having genetic mutations, including CFTR (n = 10), PRSS1 (n = 4), and SPINK1 (n = 2) mutations. Mean patient age was 31.4 years (range, 15-59) with an equal male-to-female ratio (50:50). Preoperatively, patients required an average of 185 ± 60 morphine equivalents (MEQ) (median, 123 MEQ) for preoperative pain control. No patients were taking insulin before operation. After resection with IAT, patients were discharged from the hospital with a daily average of 22 ± 4 units of insulin with 6 (38%) patients requiring fewer than 15 units of insulin at the time of discharge. At a mean follow-up of 22 months, mean insulin requirements decreased to 15 U/d (P = .0172). A total of 7 (44%) patients required 15 or fewer units daily, and 4 (25%) patients were completely insulin-independent. Average daily narcotic usage at most recent follow-up decreased to 70 MEQ (median, 0) with 10 (63%) patients currently narcotic-independent. Analyses of the 36-item short-form health survey and the McGill Pain Questionnaire demonstrated a significant improvement in quality-of-life parameters and pain assessment.

CONCLUSION

In patients who suffer from genetically linked chronic pancreatitis, pancreatic resection with IAT should be considered as an early therapeutic option to decrease chronic abdominal pain while preserving endogenous endocrine function.

Uncertainties in the classification of human cationic trypsinogen (PRSS1) variants as hereditary pancreatitis-associated mutations

BACKGROUND

Autosomal dominant hereditary pancreatitis has been conclusively linked with cationic trypsinogen (PRSS1) mutations p.R122H and p.N29I, which can be found in approximately 90% of mutation-positive cases. To date, 35 additional rare or private PRSS1 variants have been identified in subjects with hereditary or sporadic, idiopathic chronic pancreatitis. Despite the lack of sufficient genetic and functional evidence, many of these rare variants have been labelled as pancreatitis associated. This problematic trend is notably illustrated by two recent studies that classified the p.A121T PRSS1 variant as pancreatitis associated, in large part owing to its intimate proximity to arginine-122, the residue affected by the disease causing p.R122H mutation.

METHODS AND RESULTS

Here we demonstrate that the p.A121T variant is functionally innocuous and shows no verifiable association with hereditary pancreatitis, on the basis of the available inconclusive data.

CONCLUSION

This case cautions that assignment of clinical relevance to rare PRSS1 variants should not be based on a perceived analogy with genuine disease causing PRSS1 mutations, and further studies are required to prove or rule out possible low penetrance causality of rare PRSS1 variants.