Objective To investigate the assessed value of tumor-associated macrophages ( TAMs ) and KIT expression for liver metastasis in pancreatic neuroendocrine tumors (PNETs) and patients′outcome. Methods A total of 79 patients who underwent surgical resection and pathologically diagnosed as PNETs in the Department of Hepatopancreatobiliary Surgery in Sun Yat-sen Memorial Hospital from January 1995 to May 2015 were enrolled.The immunohistochemical staining of CD68 and KIT were detected and the correlations with clinicopathological factors were analyzed.Results Of 79 PNETs cases, CD68 and KIT in tumor tissue were overexpressed in 30(38%) and 35(44.3%) cases, respectively.CD68 overexpression was associated with tumor infiltration ( P<0.001 ), AJCC stage 7 ( P<0.001 ), liver metastasis ( P<0.001 ) and early recurrence (P=0.019).Patients with low CD68 level had significantly better survival than those with high CD68 expression ( P=0.0002 ).KIT overexpression was correlated with WHO 2010 and AJCC stage 7 (P<0.001;P=0.002), nonfunctional status of the tumor (P=0.002) and liver metastasis (P=0.026). The survival period of patients with low KIT expression was greatly longer than those with high KIT level (P=0.0013).CD68 and KIT co-overexpression was observed in patients with tumor invasion (P<0.001), advanced WHO and AJCC stage (both P<0.001) and better prognostic survival (P=0.0057).Multivariate analysis showed that CD68 overexpression (HR:2.9;95%CI:1.16~7.23;P=0.033) was an independent prognostic factor for PNETs.Conclusions CD68 and KIT overexpression is correlated with advanced disease stage, higher risk for liver metastasis and worse survival.CD68 is an independent prognostic factor for PNETs.

Objective To explore the effects of hepatocyte nuclear factor 1 homeobox A(HNF1A) on drug resistance of PANC1 cells to gemcitabine plus abaraxane and explore the potential mechanism. Methods 78 pancreatic cancer patients with locally advanced or distant metastasis who received gemcitabine plus abaraxane chemotherapy after surgery in Biliary and Pancreatic Surgery Department of Sun Yat-sen Memorial Hospital from March 2012 to May 2017 were enrolled. qPCR was used to detect HNF1A mRNA levels in pancreatic cancer tissue. The patients were divided into high-expression group ( n=39 ) and low-expression group (n=39) according to the median expression level of HNF1A, and the correlation of HNF1A expression with cancer clinicopathologic parameters and survival was analyzed. qPCR was used to detect HNF1A mRNA of 3 drug-sensitive cell lines (BxPC-3, CFPAC-1 and L3. 6pl) and 4 drug-resistant pancreatic cancer cell lines (PANC1, MIA PaCa-2, Hs766T and Mpanc96). Lentivirus with plasmids carrying HNF1AcDNA infection was used to establish HNF1A overexpressing PANC1 cells ( HNF1A group), and lentivirus with empty plasmids were used to infect PANC1 cells to construct the control group. The mRNA and protein expression of HNF1A and ATP binding cassette transporter family ABCC1 in HNF1A group and control group were measured by qPCR and Western Blot, respectively. The half inhibition concentration ( IC50 ) of gemcitabine plus abaraxane was detected by MTT, and cell apoptosis was examined by flow cytometry. Results Pancreatic cancer patients with high HNF1A expression had a better overall survival than those with low HNF1A expression (17. 9 months vs 12.4 months), and the difference was statistically significant (P<0.001). HNF1A low expression in pancreatic cancer tissue was significantly associated with advanced TNM stage, perineural invasion ( PNI) and short overall survival. The expression level of HNF1A was significantly down-regulated in drug-resistant PANC1 cells compared to drug-sensitive BxPC-3 cells by an average fold change of 6. 73, and the difference was statistically significant ( P<0. 001 ). In HNF1A group, the mRNA and protein levels of ABCC1 were significantly decreased compared with those in control group (0. 012 ± 0. 004vs 0. 047 ± 0. 008,0. 281 ± 0. 040 vs 0. 832 ± 0. 046,P=0. 003,P <0. 001). IC50 of HNF1A group to gemcitabine plus abraxane was decreased compared with that of control group [(26. 31 ± 2. 91)μmol/L vs (72. 63 ± 4. 07) μmol/L], and the cell apoptosis rate of HNF1A group was increased compared with that of control group [(40. 18 ± 1. 64)％ vs (21. 31 ± 1. 98)％], and the differences were statistically significant (P<0. 01). Conclusions HNF1A may induce resistance of pancreatic cancer cell to gemcitabine plus abraxane by downregulating ABCC1.

Pancreatic cancer is characterized by nerve invasion and a high mortality rate， and its pathological process depends on the complex interaction network between tumor and the nervous system. Based on the concept of “pancreatic cancer neuroecology”， this article analyzes the mechanism of action of peripheral motor nerve， sensory nerve， and central nerve in tumorigenesis， pain regulation， and cachexia formation and emphasizes the synergistic regulatory role of immune cells， Schwann cells， and extracellular matrix in the microenvironment of perineural invasion. At the same time， this article further elaborates on the metabolic interaction and chemotaxis between neuraxis and tumor， the effect on promoting chemotherapy resistance， and the dynamic relationship between neuroplasticity and tumor adaptability. In clinical practice， this article summarizes the key value of perineural invasion in prognostic evaluation， preoperative evaluation， and the selection of surgical strategy. In addition， this article reviews the basic research advances in the biomarkers and potential targets associated with perineural invasion in pancreatic cancer and points out the limitations of current model and transformation research. In the future， systematically analyzing the nerve-tumor-immune network and targeting its key nodes may provide multi-dimensional strategies and new breakthroughs for the precise intervention of pancreatic cancer， the reversal of drug resistance， and the relief of symptoms.