Recurrence in Patients Achieving Pathological Complete Response After Neoadjuvant Treatment for Advanced Pancreatic Cancer.

OBJECTIVE: The aim of this study was to characterize the patterns and treatment of disease recurrence in patients achieving a pathological complete response (pCR) following neoadjuvant chemoradiation for advanced pancreatic ductal adenocarcinoma (PDAC). SUMMARY OF BACKGROUND DATA: A pCR is an independent predictor for improved survival in PDAC. However, disease recurrence is still observed in these patients. METHODS: Patients with advanced PDAC who were treated with neoadjuvant therapy and had a pCR were identified between 2009 and 2017. Overall survival (OS) was determined from the initiation of neoadjuvant, disease-free survival (DFS) from the date of surgery, and post-recurrence survival (PRS) from the date of recurrence. Factors associated with recurrence were analyzed using a Cox-regression model. RESULTS: Of 331 patients with borderline resectable or locally advanced PDAC, 30 achieved a pCR following neoadjuvant treatment and pancreatectomy. The median DFS for pCR patients was 29 months and OS 76 months. Recurrence was observed in 14 patients. No clinicopathologic or treatment characteristics were associated with survival. The median PRS following recurrence was 25 months. Treatment following recurrence included chemotherapy, radiation or ablation, and surgical resection. Hepatectomy or completion pancreatectomy was accomplished in 2 patients that remain alive 13 and 62 months, respectively, following metastasectomy. CONCLUSIONS: A pCR following neoadjuvant therapy in patients with advanced PDAC is associated with remarkable survival, although recurrence occurs in about half of patients. Nevertheless, patients with pCR and recurrence respond well to treatment and survival remains encouraging. Advanced molecular characterization and longitudinal liquid biopsy may offer additional assistance with understanding tumor biologic behavior after achieving a pCR.

Radical antegrade modular pancreatosplenectomy versus standard distal pancreatosplenectomy for pancreatic cancer, a dual-institutional analysis.

BACKGROUND: Radical antegrade modular pancreatosplenectomy (RAMPS) has been adopted by some surgeons in the treatment of left-sided pancreatic cancer (PDAC). Low disease incidence and heterogenous disease biology make robust prospective comparison of RAMPS and standard distal pancreatosplenectomy (DPS) difficult. METHODS: Consecutive cases of chemo-naïve patients undergoing open RAMPS and DPS for PDAC between 2010-2017 at two international high-volume pancreatectomy centers were compared. Cox proportional hazard modeling was utilized for multivariate analysis. RESULTS: We identified 193 DPS and 253 RAMPS during the study period. DPS was associated with higher rates of median estimated blood loss (500 vs. 300 cc, P<0.001), median total harvested lymph nodes (18 vs. 12, P<0.001) and R0 resection (94.3% vs. 88.9%, P=0.013). There were no differences in rates of postoperative pancreatic fistula (16.5% vs. 17.8%, P=1) or postoperative hemorrhage (5.9% vs. 3.6%, P=0.385) (DPS vs. RAMPS). After controlling for significant clinical pathological parameters, RAMPS was associated with non-superior recurrence-free survival (RFS) (HR 0.29; 95% CI, 0.07-1.27, P=0.101) and overall-survival (HR 1.03; 95% CI, 0.71-1.49, P=0.895) compared with DPS. Similar results were observed in node-positive patients. CONCLUSIONS: RAMPS is safe and effective in the treatment of PDAC, but is not associated with an improvement in either RFS or overall-survival over DPS.

PIK3R3 Promotes Metastasis of Pancreatic Cancer via ZEB1 Induced Epithelial-Mesenchymal Transition.

BACKGROUND/AIMS: PIK3R3 is a regulatory subunit of phosphatidylinositol 3-kinase (PI3K) which plays an essential role in the metastasis of several types of cancer. However, whether PIK3R3 can promote the metastasis of pancreatic cancer (PC) is still unclear. In this study, we characterized the role of PIK3R3 in metastasis of PC and underlying potential mechanisms. METHODS: RT-PCR, western blot, immunofluorescence (IF) and immunohistochemistry (IHC) were applied to investigate the expression of genes and proteins in different cell lines and tissues. To assess the function of PIK3R3 and related mechanisms, the cells with RNAi-mediated knockdown or overexpression were used to perform a series of in vitro and in vivo assays. RESULTS: PIK3R3 was significantly overexpressed in pancreatic cancer tissues, especially in metastatic cancer tissues, as well as in pancreatic cancer cells. Functional assays suggested that overexpression or knockdown of PIK3R3 could respectively promote or suppress the migration and invasion of PC cells in vitro and in vivo. Further mechanism related studies demonstrated that ERK1/2-ZEB1 pathway-triggered epithelial-mesenchymal transition (EMT) might be responsible for the PIK3R3-induced PC cell migration and invasion. CONCLUSION: PIK3R3 could promote the metastasis of PC by facilitating ZEB1 induced EMT, and could act as a potential therapeutic target to limit PC metastasis.

A Yin-Yang 1/miR-30a regulatory circuit modulates autophagy in pancreatic cancer cells.

BACKGROUND: Autophagy is a highly regulated biological process that mediates the degradation of intracellular components. It is required for tumor cell metabolism and homeostasis. Yin-Yang 1 (YY1) has been reported to be involved in autophagy in several carcinomas. However, its role in autophagy in pancreatic cancer, one of the deadliest human malignancies, is unknown. Here, we investigated the function of YY1 in pancreatic cancer cells autophagy and its mechanisms of action. METHODS: The activity of cells undergoing autophagy was assessed using transmission electron microscopy, immunofluorescence, and Western blotting. A luciferase activity assay, real-time quantitative polymerase chain reaction (RT-qPCR), and chromatin immunoprecipitation (ChIP) were also used to identify putative downstream targets of YY1. RESULTS: YY1 was confirmed to regulate autophagy in pancreatic cancer cells. It was found to directly regulate the expression of miR-30a, a known modulator of autophagy-associated genes. Furthermore, overexpression of miR-30a attenuated the pro-autophagic effects of YY1. CONCLUSIONS: Cumulatively, our data suggest that miR-30a acts in a feedback loop to modulate the pro-autophagic activities of YY1. Thus, autophagy in pancreatic cancer cells may be regulated, in part, by a tightly coordinated YY1/miR-30a regulatory circuit. These findings provide a potential druggable target for the development of treatments for pancreatic cancer.

Risk factors of postoperative pancreatic fistula in patients after distal pancreatectomy: a systematic review and meta-analysis.

Postoperative pancreatic fistula (POPF) is a common complication following distal pancreatectomy (DP). However, the risk factors of this complication in patients after DP still remain controversial. The aim of our study is to estimate the association between potential risk factors and POPF. Relevant articles published up to June 21, 2016 were identified via PubMed, EMBASE, Web of Science, and The Cochrane Library. Studies that examined the risk factors of POPF following DP were enrolled. 20 articles (2070 patients) were finally included in this study. The pooled data suggested that patients with soft pancreas, higher Body Mass Index (BMI), blood transfusion, elevated intraoperative blood loss, and longer operative time had a decreased risk for POPF. However, age, gender, malignant pathology, types of stump closure, octreotide therapy, history of diabetes and chronic pancreatitis, splenectomy, multiorgan resection, main duct ligation, preoperative serum albumin levels, PGA felt wrapping, and extended lymphadenectomy could not be regarded as risk factors for POPF. Our analytic data demonstrated that pancreas texture, BMI, blood transfusion, intraoperative blood loss, and operative time were clinical predictor for POPF. This study may assist surgeons to screen patients with high risk of POPF and select appropriate treatment measures.

PEG10 overexpression induced by E2F-1 promotes cell proliferation, migration, and invasion in pancreatic cancer.

BACKGROUND: Overexpression of paternally expressed gene-10 (PEG10) is known to promote the progression of several carcinomas, however, its role in pancreatic cancer (PC) is unknown. We investigated the expression and function of PEG10 in PC. METHODS: PEG10 expression and correlation with PC progression was assessed in cancerous tissues and paired non-cancerous tissues. Further, the role of PEG10 in PC cell progression and the underlying mechanisms were studied by using small interfering RNA (Si-RNA). RESULTS: PEG10 expression was significantly higher in cancerous tissues and correlated with PC invasion of vessels and Ki-67 expression. Si-RNA mediated PEG10 knockdown resulted in inhibition of proliferation and G0/G1 cell cycle arrest, which was mediated by p21 and p27 upregulation. A decrease in PC cell invasion and migration, mediated by ERK/MMP7 pathway, was observed in PEG10 knockdown group. Further, findings of ChIP assay suggested that E2F-1 could directly enhance the expression of PEG10 through binding to PEG10 promoter. CONCLUSIONS: In conclusion, PEG10 was identified as a prognostic biomarker for PC and E2F-1 induced PEG10 could promote PC cell proliferation, invasion, and metastasis.

The Expression and Prognostic Roles of MCMs in Pancreatic Cancer.

OBJECTIVES: Minichromosome maintenance (MCM) proteins play important roles in DNA replication by interacting with other factors which participate in the regulation of DNA synthesis. Abnormal over-expression of MCMs was observed in numerous malignancies, such as colorectal cancer. However, the expression of MCMs in pancreatic cancer (PC) was less investigated so far. This study was designed to analyze the expression and prognostic roles of MCM1-10 in PC based on the data provided by The Cancer Genome Atlas (TCGA). METHODS: Pearson χ2 test was applied to evaluate the association of MCMs expression with clinicopathologic indicators, and biomarkers for tumor biological behaviors. Kaplan-Meier plots and log-rank tests were used to assess survival analysis, and univariate and multivariate Cox proportional hazard regression models were used to recognize independent prognostic factors. RESULTS: MCM1-10 were generally expressed in PC samples. The levels of some molecules were markedly correlated with that of biomarkers for S phase, proliferation, gemcitabine resistance. And part of these molecules over-expression was significantly associated with indicators of disease progression, such as depth of tumor invasion and lymph node metastasis. Furthermore, MCM2, 4, 6, 8, and 10 over-expression was remarkably associated with shorter disease free survival time, and MCM2, 4,8, and 10 over-expression was associated with shorter overall survival time. Further multivariate analysis suggested that MCM8 was an independent prognostic factor for PC. CONCLUSION: MCMs abnormal over-expression was significantly associated with PC progression and prognosis. These molecules could be regarded as prognostic and therapeutic biomarkers for PC. The roles of MCMs may be vitally important and the underlying mechanisms need to be furtherinvestigated.

Altered expression of CD226 and CD96 on natural killer cells in patients with pancreatic cancer.

The progression of pancreatic cancer (PC) is significantly associated with tumor immune escape, which may be associated with nature killer (NK) cell dysfunction. CD226, CD96, and TIGIT, which share the ligand CD155, play important roles in the regulation of NK cell function. The present study was conducted to investigate the roles of these molecules in NK cells from PC patients. Expression of these molecules on NK cells was detected from samples of 92 pancreatic cancer patients and 40 healthy controls. The expression of CD155 was also evaluated by immunohistochemistry in 88 pancreatic cancer tissues. The percentage of CD226+ and CD96+ NK cells was significantly lower in PC patients than in the healthy controls; however, the mean fluorescence intensity of CD226 and CD96 was not significantly different between the two groups. TIGIT expression on NK cells from PC patients was similar to that in the healthy controls. Additionally, the expression of CD226 was positively correlated with CD96. Further analysis demonstrated that the decrease in the percentage of CD226+ and CD96+ NK cells was associated with tumor histological grade and lymph node metastasis. Moreover, the CD155 levels in PC tissues were significantly higher than those in adjacent tissues. Our results suggest that a lower percentage of CD226+ and CD96+ NK cells may contribute to tumor immune escape in PC patients; moreover, the use of NK cells with high CD226 and CD96 expression to treat PC cells with high CD155 expression may have potential and should be explored in the future.

The level of peripheral blood circulating CD34+ cells is higher in acute promyelocytic leukemia patients with adverse prognostic factors.

INTRODUCTION: The increased flow cytometry enumeration of peripheral blood circulating CD34+ cells in patients with acute leukemia has been found in our previous work. In this study, we also demonstrated that acute promyelocytic leukemia (APL) patients not only had elevated CD34+ cell count, but also had some clinical features. METHODS: Fifty APL patients and 19 healthy volunteers were included in the study. The enumeration of circulating CD34+ cells, cytogenetic subgroup, immunophenotype analysis, and leukemic-related gene mutation detection were performed. RESULTS: Some APL patients with higher count of CD34+ cells (≤10 × 10(6)/l) usually possessed one or more poor prognostic factors (higher WBCs count, PML/RARa gene complex fusion, chemotherapy-related APL, normal karyotype/complex karyotype abnormalities, CD56/CD34 antigen positive expression, FLT3-ITD positive mutation, myelofibrosis, and marrow necrosis). A cut-off value of 10 × 10(6)/l CD34+ cells may have the power to distinguish APL patients with above adverse clinical prognostic factor from other APL subjects. CONCLUSION: The circulating CD34+ cell count appears to increase in some APL patients and a higher CD34+ cell count may be indicative of inferior survival and serve as an adverse biomarker for APL.