Reconsidering resectable oncological conditions in pancreatic tail cancer: A multicenter retrospective study on prognostic factors in pancreatic tail cancer after resection (HOPS Pt-01).

BACKGROUND: Pancreatic tail cancer (Pt-PC) is generally considered resectable when metastasis is absent, but doubts persist in clinical practice due to the variability in local tumor extent. We conducted a multicenter retrospective study to comprehensively identify prognostic factors associated with Pt-PC after resection. METHODS: We enrolled 100 patients that underwent distal pancreatectomy. The optimal combination of factors influencing relapse-free survival (RFS) was determined using the maximum likelihood method (MLM) and corrected Akaike and Bayesian information criteria (AICc and BIC). Prognostic elements were then validated to predict oncological outcomes. RESULTS: Therapeutic interventions included neoadjuvant treatment in 16 patients and concomitant visceral resection (CVR) in 37 patients; 89 patients achieved R0. Median RFS and OS after surgery were 23.1 and 37.1 months, respectively. AICc/BIC were minimized in the model with ASA-PS (≥2), CA19-9 (≥112 U/mL at baseline, non-normalized postoperatively), need for CVR, 6 pathological items (tumor diameter ≥19.5 mm, histology G1, invasion of the anterior pancreatic border, splenic vein invasion, splenic artery invasion, lymph node metastasis), and completed adjuvant treatment (cAT) for RFS. Regarding the predictive value of these 11 factors, area under the curve was 0.842 for 5-year RFS. Multivariate analysis of these 11 factors showed that predictors of RFS include CVR (hazard ratio, 2.13; 95 % confidence interval, 1.08-4.19; p = 0.028) and cAT (0.38, 0.19-0.76; p = 0.006). CONCLUSIONS: The MLM identified certain Pt-PC cases warranting consideration beyond resectable during clinical management. Particular attention should be paid to conditions requiring CVR, even though immortal time bias remains unresolved with adjuvant treatment.

A case report of carcinoma of the papilla of Vater associated with a hyperplasia-dysplasia-carcinoma sequence by pancreaticobiliary maljunction.

BACKGROUND: Pancreaticobiliary maljunction (PBM) is a known risk factor for biliary tract cancer. However, its association with carcinoma of the papilla of Vater (PVca) remains unknown. We report a case with PVca that was thought to be caused by the hyperplasia-dysplasia-carcinoma sequence, which is considered a mechanism underlying PBM-induced biliary tract cancer. CASE PRESENTATION: A 70-year-old woman presented with white stool and had a history of cholecystectomy for the diagnosis of a non-dilated biliary tract with PBM. Esophagogastroduodenoscopy revealed a tumor in the papilla of Vater, and PVca was histologically proven by biopsy. We finally diagnosed her with PVca concurrent with non-biliary dilated PBM (cT1aN0M0, cStage IA, according to the Union for International Cancer Control, 8th edition), and subsequently performed subtotal stomach-preserving pancreaticoduodenectomy. Pathological findings of the resected specimen revealed no adenomas and dysplastic and hyperplastic mucosae in the common channel slightly upstream of the main tumor, suggesting a PBM related carcinogenic pathway with hyperplasia-dysplasia-carcinoma sequence. Immunostaining revealed positivity for CEA. CK7 positivity, CK20 negativity, and MUC2 negativity indicated that this PVca was of the pancreatobiliary type. Genetic mutations were exclusively detected in tumors and not in normal tissues, and bile ducts from formalin-fixed paraffin-embedded samples included mutated-ERBB2 (Mutant allele frequency, 81.95%). Moreover, of the cell-free deoxyribonucleic acid (cfDNA) extracted from liquid biopsy mutated-ERBB2 was considered the circulating-tumor deoxyribonucleic acid (ctDNA) of this tumor. CONCLUSIONS: Herein, we report the first case of PVca with PBM potentially caused by a "hyperplasia-dysplasia-carcinoma sequence" detected using immunostaining and next-generation sequencing. Careful follow-up is required if pancreaticobiliary reflux persists, considering the possible development of PVca.

A drainage strategy for postoperative pancreatic fistula after left-sided pancreatectomy based on the wall status of collected fluid.

PURPOSE: Postoperative pancreatic fistula (POPF) after pancreatectomy is one of the severe postoperative adverse events. We aimed to clarify the outcomes of a strategy for POPF after left-sided pancreatectomy with one-step endoscopic ultrasonography-guided drainage (EUSD) and percutaneous drainage (PCD) based on the wall status of collected fluid. METHODS: From January 2012 to September 2017, 90 of 336 patients developed grade B/C POPF and were retrospectively analyzed. Primary outcome measures were the technical and clinical success and resolution rates. Secondary outcome measures were time from surgery to intervention, and time from intervention to discharge/resolution or stent/tube removal and adverse events. RESULTS: Seventeen patients underwent EUSD and 73 patients underwent PCD for POPF. The technical success rates were 100% in both the EUSD and PCD groups. The clinical success and resolution rates in the EUSD group were 100%, while those in the PCD group were 98.6%. The time from surgery to intervention was significantly longer in the EUSD group than in the PCD group (20 vs. 11 days, p < 0.001). The time from intervention to discharge/resolution was significantly shorter in the EUSD group than in the PCD group (11 vs. 22 days, p < 0.001/10 vs. 20 days, p < 0.001). The time from intervention to stent/tube removal was significantly shorter in the PCD group than in the EUSD group (20.5 vs. 873 days, p < 0.001). Adverse event rates were similar in the two groups (11.8% vs. 5.5%). CONCLUSION: A drainage strategy for POPF based on the wall status of collected fluid is appropriate.

Tricellular tight junction protein LSR/angulin-1 contributes to the epithelial barrier and malignancy in human pancreatic cancer cell line.

Lipolysis-stimulated lipoprotein receptor (LSR)/angulin-1 is a crucial molecule of tricellular contacts in the epithelial barrier of normal cells and the malignancy of cancer cells. To investigate whether LSR/angulin-1 affects the epithelial barrier and malignancy in human pancreatic cancer, human pancreatic cancer cell line HPAC was used. Treatment with EGF or TGF-ß increased the expression of LSR, but not tricellulin (TRIC), and induced the localization of LSR and TRIC to bicellular tight junctions from tricellular tight junctions. TGF-ß receptor type-1 inhibitor EW-7197 prevented changes of the distribution and the barrier function of LSR by TGF-ß. Knockdown of LSR increased cell migration, invasion, proliferation and EGF ligand amphiregulin expression and decreased the epithelial barrier. Treatment with amphiregulin induced cell migration and invasion and knockdown of amphiregulin prevented the increases of cell migration, invasion and proliferation caused by knockdown of LSR. Treatment with LSR ligand peptide angubindin-1 decreased the epithelial barrier and the expression of LSR, but not TRIC, and increased cell invasion. Knockdown of TRIC decreased cell migration and the epithelial barrier. In immunohistochemical analysis of human pancreatic cancer tissues, LSR and TRIC were found to be localized at the cell membranes of normal pancreatic ducts and well-differentiated pancreatic ductal adenocarcinomas (PDAC), whereas in poorly differentiated PDAC, LSR was weakly detected in the cytoplasm. Amphiregulin was highly expressed in the cytoplasm of well- and poorly differentiated PDAC. In pancreatic cancer, LSR contributes to the epithelial barrier and malignancy via growth factors and may be a potential targeting molecule in the therapy.

Clinical usefulness of saphenous vein graft in major arterial reconstruction during extended pancreatectomy.

PURPOSE: Extended pancreatectomy for locally advanced pancreatobiliary malignancy often involves combined major arterial resection (AR) and reconstruction (ARc). By limiting candidate inflow for ARc after combined resection of the celiac arterial system over a long distance, we evaluated whether great saphenous vein graft (GSVG) is an alternative conduit for obtaining non-anatomical arterial inflow. METHODS: ARc with GSVG conduit was undertaken prior to resection. GSVG was harvested and anastomosed end-to-side with the reconstructing artery and then mostly passed via the retroperitoneal para-inferior vena cava route. Side-to-end anastomosis of GSVG inflow was established with the right common iliac artery or abdominal aorta. RESULTS: Among 468 consecutive pancreatobiliary surgeries, ARc with GSVG was undertaken in seven cases. Primary cancers were in the pancreas in six patients and distal bile duct in one. Radical surgery was performed with pancreaticoduodenectomy in six patients and total pancreatectomy in one. Hepatic artery (HA) was concomitantly resected and reconstructed by GSVG in six patients or by the jejunal artery in one patient. Median operative time and intraoperative blood loss were 763 min and 350 ml, respectively. Serum level of AST, ALT, and LDH in patients with HA reconstruction by GSVG peaked by the second postoperative day and promptly normalized. Postoperative morbidity (CD ≥ III) was encountered in one patient. No surgical mortality was observed. Postoperative serum liver enzymes promptly decreased in ARc patients with GSVG to HA. CONCLUSION: Arterial reconstruction with GSVG prior to resection was performed securely and might help to reduce postoperative liver dysfunction.

Conversion surgery for initially unresectable biliary malignancies: a multicenter retrospective cohort study.

PURPOSE: Few studies have focused on conversion surgery for biliary malignancy; thus, it is not clear if this treatment modality can extend the survival of patients with unresectable biliary malignancy. We conducted a multicenter retrospective cohort study to evaluate the surgical outcomes of conversion surgery in this setting and analyze long-term survival. METHODS: We collected clinical data retrospectively on patients who underwent conversion surgery for biliary malignancy. RESULTS: Twenty-four patients met our inclusion criteria. Preoperative chemotherapy regimens or chemoradiation therapy regimens were administered based on the institutional criteria, and surgical procedures were chosen based on tumor location. Morbidity occurred in 16 patients (66.7%), and 1 patient died of liver failure after surgery. The overall 5-year survival rate following initial therapy was 43.2%, and the median survival time was 57.4 months. The corresponding values following surgery were 38.2% and 34.3 months, respectively. The 5-year survival rate of the 24 patients who received both chemotherapy and surgery was significantly better than that of 110 patients treated with chemotherapy only (p < 0.001). CONCLUSION: Conversion surgery for initially unresectable biliary malignancies may be feasible and achieve long-term survival for selected patients.

Current status of projects for developing cancer-related clinical practice guidelines in Japan and recommendations for the future.

BACKGROUND: The current status and adoption of cancer-related clinical practice guidelines in Japan has not been elucidated yet. The purpose of this study was to propose roles and suggestions to develop future cancer-related clinical guidelines. METHODS: A questionnaire consisting of four domains with a total of 17 questions was developed. We distributed the questionnaire to 28 specific academic organizations in Japan which have developed any cancer-related clinical practice guidelines and which were funded by the Ministry of Health, Labor, and Welfare. RESULTS: Most organizations have investigated nationwide dissemination and adoption of clinical practice guidelines. The rate of adoption in clinical practice was estimated at approximately ≥ 70%. However, organizations with smaller budgets reported surveying approximately 60% of the time, whereas the ones with larger budgets reported approximately 100% success in surveying about their guidelines. The presidents of the organizations agreed that a new organization operated directly by the national government was necessary. CONCLUSION: In Japan, to develop cancer-related clinical practice guidelines, a study of clinical validation is necessary. Sufficient funds must be available to support the project to maintain and revise the guidelines. Furthermore, legal and ethical issues should be solved before establishing any registry system.

Current status of site-specific cancer registry system for the clinical researches: aiming for future contribution by the assessment of present medical care.

BACKGROUND: The current status of site-specific cancer registry has not been elucidated, but sufficient system is found in some societies. The purpose of this study was to clear the present condition of site-specific cancer registries in Japan and to suggest for the improvement. METHODS: The questionnaire was conducted by the study group of the Ministry of Health, Labor, and Welfare. It consisted of 38 questions, conflicts of interest, clinical research method, informed consent and funding for registry. We distributed this questionnaire to 28 academic societies, which had published the clinical practice guideline(s) assessed under Medical Information Network Distribution Service (MINDS). RESULTS: The concept of the importance in assessment for medical quality by the data of the site-specific cancer registry was in good consensus. But the number of the society with the mature registry was limited. The whole-year registry with the scientific researches in the National Clinical Database (NCD) and in the Translational Research Informatics Center (TRI) might seem to be in success, because assured enhancement may be estimated. Now, academic societies have the structural factors, i.e., the financial limitation in the registry maintenance and the data analysis, and in the difficulty of employment of the researchers with skill and talent. CONCLUSIONS: To manage the site-specific cancer registry effectively, the scientific registry system will be essentially important. Each academic society had much experienced highly qualified clinical researches in past. Accordingly, the scientific suggestion and co-operation should be of great importance for the improvement.

Central pancreatectomy in portal annular pancreas for metastatic renal cell carcinoma: a case report.

BACKGROUND: Portal annular pancreas (PAP) is a rare congenital anatomical abnormality of the pancreas in which the portal vein is encircled by aberrant parenchyma, and special attention is needed for pancreatic resections. This is the first report of central pancreatectomy (CP) in a PAP for metastatic renal cell carcinoma (RCC). CASE PRESENTATION: A 76-year-old man who had a history of left nephrectomy for renal cancer not otherwise specified 36 years earlier and radical cystectomy for bladder cancer 4 years earlier was incidentally found to have a pancreatic tumor and a liver tumor. The pancreatic tumor was diagnosed as metastasis of clear cell RCC, and the liver tumor was diagnosed as moderately differentiated hepatocellular carcinoma (HCC) on preoperative histological evaluation. Preoperative computed tomography imaging showed a type 3A PAP, in which the main pancreatic duct (MPD) ran ventral to the portal vein (anteportal type), and the aberrant parenchyma was located cranial to the confluence of the portal vein and splenic vein (suprasplenic type). After adhesiotomy and partial liver resection, CP was performed. With intraoperative ultrasound guidance, the aberrant parenchyma of the PAP could be preserved, avoiding additional resection. Thus, two pancreatic transections were performed, creating a single-cut margin that contained the MPD in the distal pancreas. Oncologically safe margins were confirmed by intraoperative pathological diagnosis. The distal pancreas was reconstructed by pancreatojejunostomy in the routine procedures. The pathological diagnosis of the surgical specimens was identical to the preoperative diagnosis. A postoperative pancreatic fistula (POPF) developed from the proximal stump of the head of the pancreas, necessitating no specific treatment other than drainage. The patient showed no signs or symptoms of recurrent RCC or abnormal pancreatic function for 2 years after the operation, although a histologically proven new HCC lesion developed distant from the initial site 8 months after the operation. CONCLUSIONS: Precise preoperative evaluation of the tumor features and PAP allowed adequate surgical strategies to be planned. Intraoperative ultrasound was useful to minimize parenchymal resections of the PAP. CP is still a challenging procedure in terms of the development of POPF.

Case report: Long-term survival of a pancreatic cancer patient immunized with an SVN-2B peptide vaccine.

A 62-year-old woman who underwent surgery to treat pancreatic cancer provided written, informed consent to undergo adjuvant therapy with gemcitabine, tegafur, and uracil. However, this was stopped after only 14 days due to Grade 4 neutropenia. She was then started on vaccine therapy with Survivin 2B peptide (SVN-2B) including IFA and INF-α. Although metastatic lung tumors were identified and resected at 82 months after surgery, the patient has remained free of new or relapsed disease for 12 years thereafter. Tetramer and ELISPOT assays revealed the continuous circulation of SVN-2B-restricted cytotoxic T-lymphocytes (CTLs) in her peripheral blood, and CTL clones had specific activity for SVN-2B at 12 years after surgery. The adverse effects of the peptide vaccination were tolerable and comprised low-grade headache, nausea, and fatigue. A prognosis beyond 10 years in the face of pancreatic cancer with distant metastasis is extremely rare. This experience might indicate the value of cancer vaccination therapy.

Effects of antecolic versus retrocolic reconstruction for gastro/duodenojejunostomy on delayed gastric emptying after pancreatoduodenectomy: a systematic review and meta-analysis.

BACKGROUND: Delayed gastric emptying (DGE) is a relatively common complication after pancreatoduodenectomy (PD). The aim of this study was to determine whether DGE is affected by antecolic or retrocolic reconstruction for gastro/duodenojejunostomy after PD. METHODS: A literature search was performed of the MEDLINE (PubMed), Ovid SP, ISI Web of Knowledge, EMBASE, and Cochrane databases to identify randomized controlled trials (RCTs) and clinical observational studies related to this topic from January 1995 to November 2014. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for categorical outcomes, and mean differences (MD) using fixed-effect and random-effects models were calculated for the meta-analysis. RESULTS: Fourteen studies including 1969 patients met the inclusion criteria. Six studies were RCTs, and eight studies were clinical observational studies. DGE was less common in the antecolic reconstruction group than in the retrocolic reconstruction group (OR = 0.24 [0.12-0.48], P < 0.0001). Postoperative days to start solid foods (MD = -3.67 d [-5.10 to -2.33], P < 0.00001) and length of hospital stay (MD = -2.90 d [-5.36 to -2.33], P < 0.00001) were also significantly in favor of the antecolic reconstruction group. There was no difference in the incidence of pancreatic fistula, intra-abdominal fluid collection or abscess, biliary fistula, or mortality. However, in the subgroup analyses, using the data of six RCTs or seven studies according to the International Study Group of Pancreatic Surgery definition, there was no significant difference in the incidence of DGE. CONCLUSIONS: Antecolic reconstruction for gastro/duodenojejunostomy does not seem to offer an advantage over retrocolic reconstruction with respect to DGE after PD.

Surgical and oncological impact of main pancreatic duct spread in invasive ductal adenocarcinoma: A clinicopathological study of 184 resected cases.

BACKGROUND/OBJECTIVES: This study examined main pancreatic ductal spread in invasive ductal adenocarcinoma (IDC) of the pancreas. METHODS: Data from IDC patients who underwent radical surgery from 1990 to 2013 in our hospital were examined retrospectively. Incidence of intraductal spread of pancreatic cancer (IS), distance from the tumor edge, direction of IS and clinicopathological factors associated with the presence of IS were retrospectively examined with data from IDC patients who underwent radical surgery. RESULTS: Among 260 IDC patients who underwent surgery, 184 eligible cases, IS was identified in 42 patients (22.8%) and mean length of IS was 18.7 ± 21.6 mm. Mean distances on the ampullary and distal sides of IS were 11.1 mm and 11.6 mm. IS was significantly more frequent in localized tumors (UICC T1-2 vs. 3-4, p = 0.007), with tumor diameter ≤2 cm (p = 0.034) and in cases with scarce microscopic perineural invasion (p = 0.047). Among patients who underwent pancreaticoduodenectomy and distal pancreatectomy, IS presence (11.6 vs. 21.8%), mean distance to the contralateral side (11.4 vs. 11.6 mm), and IS ≥ 2 cm (3.3 vs. 4.7%) showed no significant differences. Overall survival did not differ significantly between IS-positive and -negative patients in the full analysis set or propensity score-matched patients (42 matched pairs). CONCLUSIONS: In setting resectional margins at 2 cm, a small proportion of cases (3.8%) showed positive surgical margins. Localized tumor (UICC: T1-2, or <2 cm in diameter) requires more care with surgical margins, warranting intraoperative frozen sections.

Remnant pancreas reconstruction with duct-to-duct anastomosis after middle pancreatectomy: a report of two cases.

Reconstruction of a remnant pancreas after middle pancreatectomy has generally been performed with a pancreaticoenterostomy. We report here two cases in which physiological reconstructive procedures were performed. The reconstructive procedures included pancreatic duct-to-duct anastomosis and parenchymal sutures with absorbable monofilament interrupted stitches. A pancreatic tube was inserted for decompression at the anastomotic site in both cases. The patients comprised one with pancreatic metastasis from renal cell carcinoma and another with a non-malignant insulinoma. The tumors were located in the pancreatic body. Although an International Study Group on Pancreatic Fistula classification grade B-pancreatic fistula was observed in each patient, they both resolved with conservative therapy. The pancreatic duct at the anastomosis site was patent in both cases, and no atrophic changes developed in the remnant pancreas in either patient. These outcomes confirmed that, in selected cases, this reconstructive procedure is safe and feasible for physiological reconstruction without involvement of the digestive tract.

Questionnaire survey for the development and publication of cancer clinical practice guidelines in Japan.

PURPOSE: To understand the current situation of the development and publication of cancer clinical practice guidelines and discuss an ideal structure in future. METHODS: A questionnaire survey pertaining to the development and publication of cancer clinical practice guidelines was conducted with funding by a Health and Labour Sciences Research Grant. Respondents included presidents and chairpersons of academic societies developing guidelines and members of the Cancer Guidelines Committee of the Japan Society of Clinical Oncology who were specialists in various cancer sites. RESULTS: Concerning the question of funding for the development and publication of the guidelines, 80.7 % of respondents indicated that partial public funding is required. As for the flow of public funds, 80.4 % of respondents thought that funds should be distributed appropriately to each academic society by a third-party organization. Regarding the question about the publication of the guidelines, 82.5 % of respondents replied that a comprehensive publication site needs to be established. In terms of the choice of organization that would be responsible for setting up and managing this site, the responses varied as follows: "a newly established organization" (38.3 %); "Center for Cancer Control and Information Services" (29.8 %); "Japan Society of Clinical Oncology" (23.4 %); and "Medical Information Network Distribution Service" (23.4 %) (multiple answers allowed). CONCLUSION: While the guidelines should be developed voluntarily by each academic society, partial public funding is also considered to be necessary for maintaining the continuous revision process. As for the publication of the guidelines, the establishment of a new comprehensive publication site would improve user convenience.

Predictors of occult metastases in potentially Resectable pancreatic ductal adenocarcinoma.

Background: Patients with resectable (R) or borderline resectable (BR) pancreatic ductal adenocarcinoma (PDAC) sometimes show unexpected liver, peritoneal, and para-aortic lymph node metastases intraoperatively. Despite radical pancreatectomy, a nonnegligible number of patients relapse within 6 months after surgery. The aim of this study was to identify the preoperative predictors of occult metastases (OM), defined as intraoperative distant metastases or within 6 months after pancreatectomy. Materials and methods: This study included patients with R and BR PDAC who underwent curative-intent pancreatectomy or staging laparoscopy between 2006 and 2021. Multivariate logistic regression and Cox hazard analyses were performed to identify the preoperative predictors of OM and to assess the impact of these factors on prognosis after pancreatectomy. Results: Of the 279 patients, OM was observed intraoperatively in 47 and postoperatively in 34. In the OM group, there were no differences in prognosis between patients who had intraoperative metastases and recurrence within 6 months (median survival time [MST], 18.1 vs. 12.9 months), and between patients who underwent pancreatectomy and those who did not (MST, 13.9 vs. 18.1 months). Preoperative tumor size ≥22 mm (odds ratio [OR], 2.03; 95 % confidence interval [CI], 1.16-3.53; p = 0.013) and preoperative CA19-9 level ≥ 118.8 U/mL (OR, 2.64; 95 % CI, 1.22-5.73; p = 0.014) were significant predictors of OM. Additionally, positive OM predictors were strong independent prognostic factors for overall survival after pancreatectomy (hazard ratio, 2.47; 95 % CI, 1.54-3.98; p < 0.001). Conclusion: Multidisciplinary treatment strategies should be considered for patients with predictors of OM to avoid inappropriate surgical interventions.

Conversion surgery for initially unresectable locally advanced biliary tract cancer: A multicenter collaborative study conducted in Japan and Korea.

BACKGROUND: Although surgical resection is the only curative treatment for biliary tract cancer, in some cases, the disease is diagnosed as unresectable at initial presentation. There are few reports of conversion surgery after the initial treatment for unresectable locally advanced biliary tract cancer. This study aimed to evaluate the efficacy and safety of conversion surgery in patients with initially unresectable locally advanced biliary tract cancer. METHODS: We retrospectively collected clinical data from groups of patients in multiple centers belonging to the Japanese Society of Hepato-Biliary-Pancreatic Surgery and Korean Association of Hepato-Biliary-Pancreatic Surgery. We analyzed two groups of prognostic factors (pretreatment and surgical factors) and their relation to the treatment outcomes. RESULTS: A total of 56 patients with initially unresectable locally advanced biliary tract cancer were enrolled in this study of which 55 (98.2%) patients received chemotherapy, and 16 (28.6%) patients received additional radiation therapy. The median time from the start of the initial treatment to resection was 6.4 months. Severe postoperative complications of Clavien-Dindo grade III or higher occurred in 34 patients (60.7%), and postoperative mortality occurred in five patients (8.9%). Postoperative histological results revealed CR in eight patients (14.3%). The median survival time from the start of the initial treatment in all 56 patients who underwent conversion surgery was 37.7 months, the 3-year survival rate was 53.9%, and the 5-year survival rate was 39.1%. CONCLUSIONS: Conversion surgery for initially unresectable locally advanced biliary tract cancer may lead to longer survival in selected patients. However, more precise preoperative safety evaluation and careful postoperative management are required.

Protein kinase Cα inhibitor protects against downregulation of claudin-1 during epithelial-mesenchymal transition of pancreatic cancer.

Protein kinase Cα (PKCα) is highly expressed in pancreatic cancer. However, the effects of PKCα on Snail and claudin-1, which play crucial roles in epithelial cell polarity during epithelial-mesenchymal transition (EMT), remain unclear. In this study, we investigated the mechanisms of regulation of Snail and claudin-1 via a PKCα signal pathway during EMT in pancreatic cancer cells and in normal human pancreatic duct epithelial cells (HPDEs). By immunostaining, overexpression of PKCα and downregulation of claudin-1 were observed in poorly differentiated human pancreatic cancer tissues and the pancreatic cancer cell line PANC-1. Treatment with the PKCα inhibitor Gö6976 transcriptionally decreased Snail and increased claudin-1 in PANC-1 cells. The PKCα inhibitor prevented upregulation of Snail and downregulation of claudin-1 during EMT induced by transforming growth factor-ß1 (TGF-ß1) treatment and under hypoxia in PANC-1 cells. The effects of the PKCα inhibitor were in part regulated via an extracellular signal-regulated kinase (ERK) signaling pathway. The PKCα inhibitor also prevented downregulation of the barrier function and fence function during EMT in well-differentiated pancreatic cancer cell line HPAC. In normal HPDEs, the PKCα inhibitor transcriptionally induced not only claudin-1 but also claudin-4, -7 and occludin without a change of Snail. Treatment with the PKCα inhibitor in normal HPDEs prevented downregulation of claudin-1 and occludin by TGF-ß1 treatment and enhanced upregulation of claudin-1, -4, -7 and occludin under hypoxia. These findings suggest that PKCα regulates claudin-1 via Snail- and mitogen-activated protein kinase/ERK-dependent pathways during EMT in pancreatic cancer. Thus, PKCα inhibitors may be potential therapeutic agents against the malignancy of human pancreatic cancer cells.

Pancreaticoduodenectomy for biliary tract carcinoma with situs inversus totalis: difficulties and technical notes based on two cases.

Situs inversus totalis (SIT) denotes complete right-left inversion of the thoracic and abdominal viscera. Diagnosis and surgical procedures for abdominal pathology in patients with SIT are technically more complicated because of mirror-image transposition of the visceral organs. Moreover, SIT is commonly associated with cardiovascular and hepatobiliary malformations, which make hepatobiliary-pancreatic surgery difficult. Two cases of pancreaticoduodenectomy for biliary tract carcinoma in patients with SIT are presented. Both patients had an anomaly of the hepatic artery. Advanced diagnostic imaging techniques were very important for careful preoperative planning and to prevent misunderstanding of the arrangement of the abdominal viscera. This facilitated the surgical team's adaptation to the mirror image of the standard procedure and helped avoid intraoperative complications due to cardiovascular and hepatobiliary malformations associated with SIT. Pancreaticoduodenectomy in patients with SIT can be performed successfully with detailed preoperative assessment, use of effective techniques by the surgeon, and appropriate support by assistants.

Transcriptional regulation of claudin-18 via specific protein kinase C signaling pathways and modification of DNA methylation in human pancreatic cancer cells.

Since claudin-18 (Cldn18) is overexpressed in precursor lesion PanIN and pancreatic duct carcinoma, it serves as a diagnostic marker and a target of immunotherapy. The stomach isoform of Cldn18, Cldn18a2 is regulated via a PKC/MAPK/AP-1-dependent pathway in PKC activator 12-O-tetradecanoylphorbol 13-acetate (TPA)-stimulated gastric cancer cells. However, little is known about how Cldn18 is regulated, not only in pancreatic duct carcinoma but also in normal human pancreatic duct epithelial cells (HPDE cells). In the present study, four pancreatic cancer cell lines, HPAF-II, HPAC, PANC-1 and BXPC3, and hTERT-HPDE cells in which the hTERT gene was introduced into HPDE cells in primary culture, were treated with TPA. In all human pancreatic cancer cell lines and hTERT-HPDE cells, Cldn18 mRNA indicated as Cldn18a2 was markedly induced by TPA and in well- or moderately differentiated human pancreatic cancer cells HPAF-II and HPAC and hTERT-HPDE cells, the protein was also strongly increased. The upregulation of Cldn18 by TPA in human pancreatic cancer cell lines was prevented by inhibitors of PKCδ, PKCε, and PKCα, whereas the upregulation of Cldn18 by TPA in hTERT-HPDE cells was prevented by inhibitors of PKCδ, PKCθ, and PKCα. Furthermore, a CpG island was identified within the coding sequence of the Cldn18 gene and treatment with the demethylating agent 5-azadeoxycytidine enhanced upregulation of Cldn18 by TPA in HPAF-II and HPAC, but not hTERT-HPDE cells. Our findings suggest that in human pancreatic cancer cells, Cldn18 is primarily regulated at the transcriptional level via specific PKC signaling pathways and modified by DNA methylation.

Transcriptional control of tight junction proteins via a protein kinase C signal pathway in human telomerase reverse transcriptase-transfected human pancreatic duct epithelial cells.

In human pancreatic cancer, integral membrane proteins of tight junction claudins are abnormally regulated, making these proteins promising molecular diagnostic and therapeutic targets. However, the regulation of claudin-based tight junctions remains unknown not only in the pancreatic cancer cells but also in normal human pancreatic duct epithelial (HPDE) cells. To investigate the regulation of tight junction molecules including claudins in normal HPDE cells, we introduced the human telomerase reverse transcriptase (hTERT) gene into HPDE cells in primary culture. The hTERT-transfected HPDE (hTERT-HPDE) cells were positive for the pancreatic duct epithelial markers such as CK7, CK19, and carbonic anhydrase isozyme 2 and expressed epithelial tight junction molecules claudin-1, -4, -7 and, -18, occludin, JAM-A, ZO-1, ZO-2, and tricellulin. By treatment with fetal bovine serum or 12-O-tetradecanoylphorbol 13-acetate (TPA), the tight junction molecules were up-regulated at the transcriptional level via a protein kinase C (PKC) signal pathway. A PKC-alpha inhibitor, Gö6976, prevented up-regulation of claudin-4 by TPA. Furthermore, a PKC-delta inhibitor, rottlerin, prevented up-regulation of claudin-7, occludin, ZO-1, and ZO-2 by TPA. By GeneChip analysis, up-regulation of the transcription factor ELF3 was observed in both fetal bovine serum- and TPA-treated cells. Treatment with small interfering RNAs of ELF3 prevented up-regulation of claudin-7 by TPA. These data suggest that tight junctions of normal HPDE cells were at least in part regulated via a PKC signal pathway by transcriptional control.