The GFPT2-O-GlcNAcylation-YBX1 axis promotes IL-18 secretion to regulate the tumor immune microenvironment in pancreatic cancer.

The immunosuppressive microenvironment caused by several intrinsic and extrinsic mechanism has brought great challenges to the immunotherapy of pancreatic cancer. We identified GFPT2, the key enzyme in hexosamine biosynthesis pathway (HBP), as an immune-related prognostic gene in pancreatic cancer using transcriptome sequencing and further confirmed that GFPT2 promoted macrophage M2 polarization and malignant phenotype of pancreatic cancer. HBP is a glucose metabolism pathway leading to the generation of uridine diphosphate N-acetylglucosamine (UDP-GlcNAc), which is further utilized for protein O-GlcNAcylation. We confirmed GFPT2-mediated O-GlcNAcylation played an important role in regulating immune microenvironment. Through cellular proteomics, we identified IL-18 as a key downstream of GFPT2 in regulating the immune microenvironment. Through CO-IP and protein mass spectrum, we confirmed that YBX1 was O-GlcNAcylated and nuclear translocated by GFPT2-mediated O-GlcNAcylation. Then, YBX1 functioned as a transcription factor to promote IL-18 transcription. Our study elucidated the relationship between the metabolic pathway of HBP in cancer cells and the immune microenvironment, which might provide some insights into the combination therapy of HBP vulnerability and immunotherapy in pancreatic cancer.

Deubiquitinating PABPC1 by USP10 upregulates CLK2 translation to promote tumor progression in pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is extremely malignant with limited treatment options. Deubiquitinases (DUBs), which cleave ubiquitin on substrates, can regulate tumor progression and are appealing therapeutic targets, but there are few related studies in PDAC. In our study, we screened the expression levels and prognostic value of USP family members based on published databases and selected USP10 as the potential interventional target in PDAC. IHC staining of the PDAC microarray revealed that USP10 expression was an adverse clinical feature of PDAC. USP10 promoted tumor growth both in vivo and in vitro in PDAC. Co-IP experiments revealed that USP10 directly interacts with PABPC1. Deubiquitination assays revealed that USP10 decreased the K27/29-linked ubiquitination level of the RRM2 domain of PABPC1. Deubiquitinated PABPC1 was able to couple more CLK2 mRNA and eIF4G1, which increased the translation efficiency. Replacing PABPC1 with a mutant that could not be ubiquitinated impaired USP10 knock-down-mediated tumor suppression in PDAC. Targeting USP10 significantly delayed the growth of cell-derived xenograft and patient-derived xenograft tumors. Collectively, our study first identified USP10 as the DUB of PABPC1 and provided a rationale for potential therapeutic options for PDAC with high USP10 expression.

Inhibition of epithelial-to-mesenchymal transition augments antitumor efficacy of nanotherapeutics in pancreatic ductal adenocarcinoma.

Intrinsic drug resistance mechanisms of tumor cells often reduce intracellular drug concentration to suboptimal levels. Epithelial-to-mesenchymal transition (EMT) is a pivotal process in tumor progression and metastasis that confers an aggressive phenotype as well as resistance to chemotherapeutics. Therefore, it is imperative to develop novel strategies and identify new targets to improve the overall efficacy of cancer treatment. We developed SN38 (active metabolite of irinotecan)-assembled glycol chitosan nanoparticles (cSN38) for the treatment of pancreatic ductal adenocarcinoma (PDAC). Furthermore, cSN38 and the TGF-ß1 inhibitor LY364947 formed composite nanoparticles upon self-assembly (cSN38 + LY), which obviated the poor aqueous solubility of LY364947 and enhanced drug sensitivity. The therapeutic efficacy of cSN38 + LY nanotherapeutics was studied in vitro and in vivo using suitable models. The cSN38 nanoparticles exhibited an antitumor effect that was significantly attenuated by TGF-ß-induced EMT. The cellular uptake of SN38 was impeded during EMT, which affected the therapeutic efficacy. The combination of LY364947 and cSN38 markedly enhanced the cellular uptake of SN38, increased cytotoxic effects, and inhibited EMT in PDAC cells in vitro. Furthermore, cSN38 + LY significantly inhibited PDAC xenograft growth in vivo. The cSN38 + LY nanoparticles increased the therapeutic efficacy of cSN38 via repressing the EMT of PDAC cells. Our findings provide a rationale for designing nanoscale therapeutics to combat PDAC.

SIGLEC15 amplifies immunosuppressive properties of tumor-associated macrophages in pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) usually presents infrequent infiltration of T lymphocytes. The known immune-checkpoint inhibitors to date focus on activating T cells and manifest limited effectiveness in PDAC. SIGLEC15 was identified as a novel tumor-associated macrophage (TAM)-related immune-checkpoint in other cancer types, while its immunosuppressive role and clinical significance remained unclear in PDAC. In our study, SIGLEC15 presented immunosuppressive relevance in PDAC via bioinformatic analysis and expressed on TAM and PDAC cells. SIGLEC15+ TAM, rather than SIGLEC15+ PDAC cells or SIGLEC15- TAM, correlated with poor prognosis and immunosuppressive microenvironment in the PDAC microarray cohort. Compared with SIGLEC15- TAM, SIGLEC15+ TAM presented an M2-like phenotype that could be modulated by SIGLEC15 in a tumor cell-dependent manner. In mechanism, SIGLEC15 interacted with PDAC-expressed sialic acid, preferentially α-2, 3 sialic acids, to stimulate SYK phosphorylation in TAM, which further promoted its immunoregulatory cytokines and chemokines production. In vivo, SIGLEC15+ TAM also presented an M2-like phenotype, accelerated tumor growth, and facilitated immunosuppressive microenvironment, which was greatly abolished by SYK inhibitor. Our study highlighted a novel M2-promoting function of SIGLEC15 and strongly suggested SIGLEC15 as a potential immunotherapeutic target for PDAC.

WITHDRAWN: Individualized and pancreatic duct diameter-based strategy for pancreaticoenteric anastomosis during pancreaticoduodenectomy.

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

Silencing of LAMC2 Reverses Epithelial-Mesenchymal Transition and Inhibits Angiogenesis in Cholangiocarcinoma via Inactivation of the Epidermal Growth Factor Receptor Signaling Pathway.

Cholangiocarcinoma (CCA) is a malignant cancer that is associated with high mortality rates. The relationship between laminin γ 2 chain gene (LAMC2) and epidermal growth factor receptor (EGFR) has been previously documented in gastric cancer and oral squamous cell carcinoma. This study investigates the role of LAMC2 in epithelial-mesenchymal transition (EMT) and angiogenesis in CCA and explores the underlying mechanism(s). Differentially expressed genes related to CCA were initially screened using a microarray analysis, and the interaction between LAMC2 and the EGFR signaling pathway was identified. To determine the regulatory effects of LAMC2 on CCA progression, LAMC2 was silenced or overexpressed and the EGFR signaling pathway was activated or blocked. Subsequently, the regulation effects of LAMC2 were evaluated on the expression of EMT markers, invasion and migration of CCA cells, as well as microvessel density in nude mice. Microarray analysis demonstrated that highly expressed LAMC2 is linked to CCA development, which involves the EGFR signaling pathway. When LAMC2 expression was increased, the EGFR signaling pathway and EMT were activated in CCA tissues. Silencing of LAMC2 as well as EGFR signaling pathway inhibition led to suppression of EMT, cell invasion, and migration abilities in vitro, as well as angiogenesis in vivo. This study demonstrates that LAMC2 silencing suppresses the activity of the EGFR signaling pathway, thus functioning as a tumor suppressor in CCA.

Cross-talk among AFAP1-AS1, ACVR1 and microRNA-384 regulates the stemness of pancreatic cancer cells and tumorigenicity in nude mice.

BACKGROUND: Pancreatic cancer (PC) represents one of the most aggressive forms of cancer. The role of long non-coding RNAs (lncRNAs) has been highlighted in various malignancies including PC. The aim of the present study was to investigate the effects associated with actin filament-associated protein 1 antisense RNA 1 (AFAP1-AS1) on the progression of PC and the underlying mechanism. METHODS: Microarray-based gene expression profiling of PC was performed to identify PC-related lncRNAs, after which the expression of AFAP1-AS1 and cancer stem cell (CSC) markers in PC tissues and cells were determined accordingly. The potential microRNA-384 (miR-384) capable of binding to AFAP1-AS1, in addition to its ability to regulate activin receptor A type I (ACVR1) were analyzed. In order to investigate the effect of the AFAP1-AS1/miR-384/ACVR1 axis on self-renewal ability, tumorigenicity, invasion, migration and stemness of PC cells, shRNA-AFAP1-AS1, miR-384 mimic and inhibitor were cloned into cells. RESULTS: High expression of AFAP1-AS1 and ACVR1 with low expression of miR-384 were detected in PC tissues. ACVR1 was determined to be down-regulated when miR-384 was overexpressed, while the inhibition of AFAP1-AS1 decreased its ability to binding competitively to miR-384, resulting in the down-regulation of ACVR1 and enhancing miR-384 expression, ultimately inhibiting the progression of PC. The knockdown of AFAP1-AS1 or overexpression of miR-384 was confirmed to impair PC cell self-renewal ability, tumorigenicity, invasion, migration and stemness. CONCLUSIONS: Taken together, AFAP1-AS1 functions as an endogenous RNA by competitively binding to miR-384 to regulate ACVR1, thus conferring inhibitory effects on PC cell stemness and tumorigenicity.

Methyl-CpG Binding Domain Protein 2 Inhibits the Malignant Characteristic of Lung Adenocarcinoma through the Epigenetic Modulation of 10 to 11 Translocation 1 and miR-200s.

It has been reported that disorders of epigenetic modulation play a critical role in carcinogenesis. Methyl-CpG binding domain protein 2 (MBD2) is known to act as an epigenetic modulator in various types of tumors; however, the role of MBD2 in lung adenocarcinoma (LUAD) remains unclear. Herein, we demonstrated the down-regulation of MBD2 in LUAD compared with adjacent nontumor tissues. The down-regulation of MBD2 in LUAD was correlated with metastasis and poor survival. In addition, MBD2 inhibited tumor metastasis by maintaining the expression of the miR-200s, which suppressed the invasive properties of tumors. Also, MBD2 positively correlated with 5-hydroxymethylcytosine content in the promoter of miR-200s. The conventional view is that MBD2 acts as a transcriptional suppressor. However, the data revealed that MBD2 may act as a transcriptional activator by recruiting 10 to 11 translocation 1 (TET1) and forming a chromatin-remodeling complex. The MBD2-TET1 complex locates to the TET1 promoter and removes the methyl residues in this region, thereby activating TET1 transcription. TET1 also acted as a tumor suppressor in LUAD. Taken together, the data demonstrate the correlation between MBD2, miR-200s, and TET1, and tumor suppressive effect of MBD2 through up-regulation of TET1 and the miR-200s.

Circular RNA hsa_circ_000984 promotes colon cancer growth and metastasis by sponging miR-106b.

Circular RNAs (circRNAs) as a novel type of noncoding RNAs (ncRNAs) are widely studied in the development of human various diseases, including cancer. Here, we found circular RNA hsa_circ_000984 encoded by the CDK6 gene was remarkably upregulated in the tissues of colorectal cancer (CRC) patients and in the CRC cell lines. Moreover, high expression level of hsa_circ_000984 was significantly associated with advanced colorectal cancer. Further analysis revealed that hsa_circ_000984 knockdown could inhibit cell proliferation, migration, invasion in vitro and tumor formation in vivo in CRC cell lines. Mechanically, we found that hsa_circ_000984 may act as a competing endogenous RNA (ceRNA) by competitively binding miR-106b and effectively upregulate the expression of CDK6, thereby inducing a series of malignant phenotypes of tumor cells. Taken together, these observations suggest that the hsa_circ_000984 could mediate the expression of gene CDK6 by acting as a ceRNA, which may contribute to a better understanding of between the regulatory miRNA network and CRC pathogenesis.

Hypermethylation of the CHRDL1 promoter induces proliferation and metastasis by activating Akt and Erk in gastric cancer.

CHRDL1 (Chordin-like 1) is a secreted protein that acts as an antagonist of bone morphogenetic protein (BMP). BMP plays a role as an activator of BMP receptor II (BMPR II), which mediates extracellular to intracellular signal transmission and is involved in carcinogenesis and metastasis. Herein, we report that CHRDL1 expression was significantly down-regulated in gastric cancer tissues and associated with poor survival. Clinic-pathological parameters demonstrated a close relationship between low CHRDL1 expression and metastasis. In vitro, CHRDL1 knockdown promoted tumor cell proliferation and migration through BMPR II by activating Akt, Erk and ß-catenin. Furthermore, we observed the hypermethylation of the CHRDL1 promoter in gastric cancer, which induced low expression of CHRDL1 and decreased its secretion to the supernatant. Finally, in vivo experiments confirmed that CHRDL1 acted as a tumor suppressor gene in suppressing tumor growth and metastasis.

Indocyanine green retention is a potential prognostic indicator after splenectomy and pericardial devascularization for cirrhotic patients.

BACKGROUND: Splenectomy and pericardial devascularization (SPD) is an effective treatment of upper gastrointestinal bleeding and hypersplenism in cirrhotic patients with portal hypertension. Indocyanine green retention at 15 minutes (ICGR15) was reported to offer better sensitivity and specificity than the Child-Pugh classification in hepatectomy, but few reports describe ICGR15 in SPD. The present study was to evaluate the prognostic value of ICGR15 for cirrhotic patients with portal hypertension who underwent SPD. METHODS: From January 2012 to January 2015, 43 patients with portal hypertension and hypersplenism caused by liver cirrhosis were admitted in our center and received SPD. The ICGR15, Child-Pugh classification, model for end-stage liver disease (MELD) score, and perioperative characteristics were analyzed retrospectively. RESULTS: Preoperative liver function assessment revealed that 34 patients were Child-Pugh class A with ICGR15 of 13.6%-43.0% and MELD score of 7-20; 8 patients were class B with ICGR15 of 22.8%-40.7% and MELD score of 7-17; 1 patient was class C with ICGR15 of 39.7% and MELD score of 22. The optimal ICGR15 threshold for liver function compensation was 31.2%, which offered a sensitivity of 68.4% and a specificity of 70.8%. Univariate analysis showed preoperative ICGR15, MELD score, surgical procedure, intraoperative blood loss, and autologous blood transfusion were significantly different between postoperative liver function compensated and decompensated groups. Multivariate regression analysis revealed that ICGR15 was an independent risk factor of postoperative liver function recovery (P=0.020). CONCLUSIONS: ICGR15 has outperformed the Child-Pugh classification for assessing liver function in cirrhotic patients with portal hypertension. ICGR15 may be a suitable prognostic indicator for cirrhotic patients after SPD.

Successful laparoscopic common bile duct exploration in a patient with factor V deficiency, a case report and review of literature.

Factor V deficiency is a rare bleeding disorder. Fresh frozen plasma (FFP) is the only source of factor V because factor V concentrates is not available now. We present here a patient had concomitant gallbladder and common bile (CBD) stones with factor V deficiency. The patient is successfully treated by laparoscopic CBD exploration and cholecystectomy with perioperative fresh frozen plasma transfusion. To best of our knowledge, this is the first report of laparoscopic surgery successfully performed in a factor V deficiency patient. Our result suggest that laparoscopic surgery in a factor V deficient patient can be performed safely if normal coagulation profile is achieved after injection of FFP. Our experience in this case also indicate that the incidence of delayed bleeding after surgery is low once hemostasis is successfully obtained during operation and there is no need to continue FFP infusion beyond day 2 postoperative.

Functional Genetic Variations at the microRNA Binding-Site in the CD44 Gene Are Associated with Risk of Colorectal Cancer in Chinese Populations.

CD44 as one of the most putative stem cell markers plays a key role in many cellular processes, including cancer cell growth and migration. Functional single nucleotide polymorphisms (SNPs) of CD44 may modulate its gene functions and thus cancer risk. In the current study, we investigated if polymorphisms in the 3'-untranslated region (UTR) of CD44 are associated with increased susceptibility to colorectal cancer (CRC) by conducting a case-control study of 946 CRC patients and 989 cancer-free controls. Three polymorphisms (rs13347C/T, rs10836347C/T, rs11821102G/A) in the 3'-UTR of CD44 were genotyped. We found that the variant genotypes (CT and TT) of rs13347 (adjusted odds ratio (OR)=1.79, 95% confidence interval (CI)=1.50-2.17) increased an individual's susceptibility to CRC, compared with rs13347CC homozygous genotypes. We also found that CRC patients with the CT/TT genotype had a 1.6-fold increased risk for developing advanced (stage III + IV) CRC. Furthermore, functional assays showed that the C to T base change at rs13347C/T disrupts the binding site for the microRNA hsa-mir-509-3p, thereby increasing CD44 transcriptional activity and expression level. These findings suggest that the rs13347C/T in microRNA binding site may be potential biomarkers for genetic susceptibility to CRC.

Rare cause of upper gastrointestinal bleeding owing to hepatic cancer invasion: a case report.

Upper gastrointestinal bleeding refers to bleeding that arises from the gastrointestinal tract proximal to the ligament of Treitz. The primary reason for gastrointestinal bleeding associated with hepatocellular carcinoma is rupture of a varicose vein owing to pericardial hypotension. We report a rare case of gastrointestinal bleeding with hepatocellular carcinoma in a patient who presented with recurrent gastrointestinal bleeding. The initial diagnosis was gastric cancer with metastasis to the multiple lymph nodes of the lesser curvature. The patient underwent exploratory laparotomy, which identified two lesions in the gastric wall. Total gastrectomy and hepatic local excision was then performed. Pathological results indicated that the hepatocellular carcinoma had invaded the stomach directly, which was confirmed immunohistochemically. The patient is alive with a disease-free survival of 1 year since the surgery. Hepatocellular carcinoma with gastric invasion should be considered as a rare cause of upper gastrointestinal bleeding in hepatocellular carcinoma patients, especially with lesions located in the left lateral hepatic lobe. Surgery is the best solution.

Cordycepin down-regulates multiple drug resistant (MDR)/HIF-1α through regulating AMPK/mTORC1 signaling in GBC-SD gallbladder cancer cells.

Gallbladder cancer is the most common malignancy of the bile duct, with low 5-year survival rate and poor prognosis. Novel effective treatments are urgently needed for the therapy of this disease. Here, we showed that cordycepin, the bioactive compound in genus Cordyceps, induced growth inhibition and apoptosis in cultured gallbladder cancer cells (Mz-ChA-1, QBC939 and GBC-SD lines). We found that cordycepin inhibited mTOR complex 1 (mTORC1) activation and down-regulated multiple drug resistant (MDR)/hypoxia-inducible factor 1α (HIF-1α) expression through activating of AMP-activated protein kinase (AMPK) signaling in gallbladder cancer GBC-SD cells. Contrarily, AMPKα1-shRNA depletion dramatically inhibited cordycepin-induced molecular changes as well as GBC-SD cell apoptosis. Further, our results showed that co-treatment with a low concentration cordycepin could remarkably enhance the chemosensitivity of GBC-SD cells to gemcitabine and 5-fluorouracil (5-FU), and the mechanism may be attributed to AMPK activation and MDR degradation. In summary, cordycepin induces growth inhibition and apoptosis in gallbladder cancer cells via activating AMPK signaling. Cordycepin could be a promising new drug or chemo-adjuvant for gallbladder cancer.

[Selective exclusion of hepatic outflow and inflow in hepatectomy for huge hepatic tumor].

OBJECTIVE: To evaluate the effects of selective hepatic vascular exclusion (SHVE) on prevention of serious hemorrhage and air embolism during hepatectomy and on the liver function after operation. METHODS: From January 2004 to March 2007, 29 huge hepatic tumors were resected in our department. Both SHVE and Pringle maneuver were used to control the blood loss during hepatectomy. They were divided into two groups: SHVE group (15 cases) and Pringle group (14 cases). Data regarding the intraoperative and postoperative courses of the patients were analyzed. RESULTS: There was no significant difference between the two groups regarding the age, sex, tumor size, cirrhosis, HbsAg positive rate and operating time (P > 0.05). Intraoperative blood loss was reduced significantly in the SHVE group (P < 0.05). The serum prealbumin levels on the postoperative day 1, 3 and 7 in SHVE group were significantly higher than those in the Pringle group (P < 0.05). The serum ALT value in SHVE group was significantly lower than that in the Pringle group on postoperative day 1, 3 and 7. The mean drainage volume in SHVE group was significantly less than that in the Pringle group on postoperative day 1 and 2. Liver failure occurred in two cases of the Pringle group, while no one in the SHVE group. Rupture of hepatic vein with massive blood loss occurred in 3 cases and air embolism in one case of the Pringle group, but did not occur in any case of the SHVE group. CONCLUSION: When the selective exclusion of hepatic outflow and inflow is applied in hepatectomy, the resection rate of huge hepatic tumors and operative tolerance of hepatectomy are improved. It is a safe and rational operation type, and provides an optimal choice for hepatectomy.

Surgical treatment for Nevin stage IV and V gallbladder carcinoma: report of 70 cases.

BACKGROUND: The role of aggressive surgery for end-stage gallbladder carcinoma is controversial. This retrospective study was designed to evaluate the outcome of surgical treatment for Nevin stage IV and V gallbladder carcinoma at a single institution. METHODS: A retrospective analysis was made on 70 patients with Nevin stage IV and V gallbladder carcinoma undergoing surgical treatment from January 1993 to June 2004. RESULTS: There were 22 cases of stage IV and 48 of stage V. Cholecystectomy was performed in 37 cases with a resection rate of 53%, 9 cases received radical resection, 13 extended radical resection, and 15 palliative resection. The curative resection rate was 31% and the morbidity rate was 36%. Postoperative 1-, 3-, 5-year survival rates of curative and palliative resection were 69%, 33%, 8% and 27%, 13%, 0, respectively (P<0.01). The 1- and 3-year survival rates of patients undergoing exploratory laparotomy only were 3% and 0, respectively. CONCLUSIONS: Nevin stage IV and V gallbladder carcinoma should be treated by aggressive surgery. Curative resection is promising in the improvement of long-term survival rate.

[Establishment of a porcine model of acute hepatic failure by intraportal injection of D-galactosamine and lipopolysaccharide].

OBJECTIVE: To develop a clinically relevant porcine model of acute hepatic failure (AHF). METHODS: Twenty-two healthy pigs were randomly divided into 5 groups: group I (n = 3, intraportally administered with normal saline), group II [n = 5, intraportally administered with 1 microg/kg of lipopolysaccharide (LPS)], group III [n = 5, intraportally administered with 0.5 g/kg of D-galactosamine (D-Gal)], group IV (n = 6, intraportally administered with 0.5 g/kg of D-Gal plus 1 microg/kg LPS), and group V [n = 3, intraportally administered with 0.5 g/kg of D-Gal plus 1 microg/kg LPS and then receiving auxiliary partial orthotopic liver transplantation (APOLT)], Blood samples were collected to examine the arpartate transaminase (AST), total bilirubin, lactic acid, blood ammonia, prothrombin time (PT), blood sugar, and creatine at different time points. Autopsy was performed on the dead animals. Eight days after the APOLT laparotomy was performed again on the surviving pigs to take specimens of the original and transplanted liver to undergo pathological examination. RESULTS: All the pigs in the groups I and II survived with minimal changes in liver function tests. Two of the 5 pigs in the group III died (40%), 5 pigs in the group IV (5/6, 83%) died within 120 h, with a significant increase in aspartate transaminase 48 h after (4912 U/L +/- 759 U/L). In comparison with those of the group 1 and 2, the TBIL, blood ammonia, lactic acid, and PT 48 h after of the group 4 were all significantly higher and the blood sugar was significantly lower (all P < 0.05). Reversal of AHF in the pigs in the group V following APOLT was observed and the liver function returned near to normal level on the 7th postoperative day and regeneration of the native liver was confirmed histologically. CONCLUSION: The porcine model of AHF induced by a combination of D-gal (0.5 g/kg) and LPS (1 microg/kg) will be of much use in the development of APOLT for AHF.

Pancreatectomy combined with superior mesenteric-portal vein resection: report of 32 cases.

BACKGROUND: Resection of the superior mesenteric-portal vein (SMPV) during pancreatoduodenectomy is disputed. Although the morbidity and mortality of patients after this operation are acceptable, survival is limited. In this study, we evaluated the morbidity, mortality and survival of patients with ductal adenocarcinoma of the pancreas who had undergone pancreatectomy with en bloc portal vein resection. METHODS: A total of 32 patients with ductal adenocarcinoma of the pancreas who had undergone pancreatectomy with SMPV resection between 1999 and 2003 were retrospectively analyzed. In addition, they were categorized into two groups according to the invasion of the wall of the portal vein: group A (n=12),extended compression of the wall of the portal vein by surrounding carcinoma without true invasion and group B (n=20), true invasion including intramural and transmural invasion. RESULTS: The morbidity of the 32 patients was 31.25%. There was no operative death, and the overall 1-,3-year survival rates were 59% and 16%, respectively. The mean survival time of patients with microscopically positive margin was only 5.6 months as compared with 20 months in patients with microscopically negative margin. No differences in tumor size, margin positivity, nodal positivity, and 1-, 3-year survival rates were observed between the two groups. CONCLUSIONS: If selected carefully, pancreatectomy combined with SMPV resection can be performed safely, without increase in the morbidity and mortality. SMPV resection should be performed only when a margin-negative resection is expected to be achieved. SMPV invasion is not associated with histologic parameters suggesting a poor prognosis.