Pumilio RNA binding family member 1 deficiency activates anti-tumor immunity in hepatocellular carcinoma via restraining M2 macrophage polarization.

Pumilio RNA-binding family member 1 (PUM1) has been implicated in both the progression of colorectal cancer and the regulation of inflammation. The role of PUM1 in the polarization of tumor-associated macrophages (TAMs) into the M2 phenotype has not yet been reported in hepatocellular carcinoma. Using the PUM1-knockout mice model, flow cytometry, and IHC, we validated the role of PUM1 in hepatocellular carcinoma (HCC) TAMs. One-way analysis of variance (ANOVA) or student's t-tests was used to compare the experimental groups. We found that PUM1 inhibited anti-tumor immunity in HCC through TAM-mediated inhibition of CD8+ T cells. We also showed that PUM1 promotes the transformation of TAMs into pro-tumorigenic M2-like phenotypes by activating cAMP signaling pathway. This study emphasized the potential of PUM1 as a target for immunotherapy in HCC through TAMs. The present study revealed the molecular mechanism underlying the pro-tumor role of PUM1 in HCC.

PI3K/ c-Myc/AFF4 axis promotes pancreatic tumorigenesis through fueling nucleotide metabolism.

MLL-AFF4 fusion gene has been discovered in acute leukemia, whether AFF4 alone plays a role in tumor, especially pancreatic tumorigenesis, is still elusive. Increasing evidence suggests that cancer cells altered nucleotide metabolism during tumorigenesis. In present study, we observed AFF4 overexpression promoted cell proliferation, colony formation and cell cycle progression while loss of AFF4 impairs above phenotypes of pancreatic ductal carcinoma (PDAC) cells. Using RNA-profiling, we revealed that HPRT1 and IMPDH2, two enzymes in the nucleotide metabolism pathway, were upregulated following AFF4 overexpression. Simultaneous expression of HPRT1 and IMPDH2 would mainly rescue the phenotypes of cells lacking AFF4. Additionally, xenograft study proved HPRT1 and IMPDH2 genetically function in the downstream of AFF4, which was recruited by PAX2 when CDK9 mediated AFF4 phosphorylation at S388 and drove HPRT1 and IMPDH2 expression. We further discovered PI3K/c-Myc axis is required for AFF4 expression in PDAC cells. Finally, we obtained the positive correlation between c-Myc and AFF4 or AFF4 and HPRT1/IMPDH2 in clinical PDAC samples. Otherwise, we conducted data-mining and found that the expression levels of AFF4 and HPRT1/IMPDH2 are correlated with patients' prognosis, establishing AFF4 as a potential biomarker and therapeutic target for PDAC.

Risk factors of positive resection margin differ in pancreaticoduodenectomy and distal pancreatosplenectomy for pancreatic ductal adenocarcinoma undergoing upfront surgery.

OBJECTIVE: Positive resection margin indicates worse prognosis. The present study identified the independent risk factors of R1 resection in pancreaticoduodenectomy (PD) and distal pancreatosplenectomy (DP) for patients with pancreatic ductal adenocarcinoma (PDAC). METHOD: Consecutive patients who were operated from 1st December 2017 to 30th December 2018 were analyzed retrospectively. A standardized pathological examination with digital whole-mount slide images (DWMSIs) was utilized for evaluation of resection margin status. R1 was defined as microscopic tumor infiltration within 1 mm to the resection margin. The potential risk factors of R1 resection for PD and DP were analyzed separately by univariate and multivariate logistic regression analyses. RESULTS: For the 192 patients who underwent PD, and the 87 patients who underwent DP, the R1 resection rates were 31.8% and 35.6%, respectively. Univariate analysis on risk factors of R1 resection for PD were tumor location, lymphovascular invasion, N staging, and TNM staging; while those for DP were T staging and TNM staging. Multivariate logistic regression analysis showed the location of tumor in the neck and uncinate process, and N1/2 staging were independent risk factors of R1 resection for PD; while those for DP were T3 staging. CONCLUSIONS: The clarification of the risk factors of R1 resection might clearly make surgeons take reasonable decisions on surgical strategies for different surgical procedures in patients with PDAC, so as to obtain the first attempt of R0 resection.

Incidence of bifid pancreatic duct in pancreaticoduodenectomy and its impact on clinically relevant postoperative pancreatic fistula.

Objectives: This study aimed to examine the incidence of bifid pancreatic duct (BPD) in pancreaticoduodenectomy (PD) and clarify its impact on clinically relevant postoperative pancreatic fistula (CR-POPF). Background: Until now, all the literature about BPD during PD are published as case reports, and the incidence of BPD in PD and its impact on CR-POPF remain unknown. Results: A total of 438 consecutive PDs were divided into two groups: the former year group and the latter year group. The former year group included 215 consecutive PDs, while the latter year group included 223. In the latter year group, we found 16 BPDs during PD (O-BPD); the incidence of O-BPD is 7.17%. Of them, there were eight patients who had BPD in the preoperative imaging (I-BPD). All the I-BPDs are O-BPDs; which means that 50% of O-BPDs were a single pancreatic duct in the preoperative imaging (I-SPD). There were 17 I-BPDs in the 438 consecutive PDs; the incidence of I-BPD is 3.88%. In the former year group, the rate of severe complications of I-BPD and I-SPD is 77.78% and 27.18%, respectively (p = 0.003); the rate of CR-POPF of I-BPD is higher than I-SPD, 55.56% vs. 27.18%, but there were no statistically significant differences. In the latter year group, the rate of severe complications of O-BPD and O-SPD is 50% and 18.36%, and the rate of CR-POPF of O-BPD and O-SPD is 37.5% and 22.22%, respectively; both of them have statistically significant differences, and the p-value is 0.003 and 0.006, respectively. In the subgroup analysis, both the rate of severe complications and the rate of CR-POPF of I-BPD were higher than O-BPD, 77.78% vs. 50%, and 55.56% vs. 37.5%, but there were no statistically significant differences in both of them; the p-value is 0.174 and 0.434, respectively. Univariate and multivariate analyses showed that BPD was an independent risk factor of CR-POPF. Conclusions: The incidence of O-BPD in PD is 7.17%, 50% of O-BPDs were I-SPD, and the incidence of I-BPD is 3.88%. BPD is an independent risk factor of CR-POPF. The suture closure method may be a simple, safe, and effective method in dealing with BPD in PD.

UBE2C promotes the progression of pancreatic cancer and glycolytic activity via EGFR stabilization-mediated PI3K-Akt pathway activation.

Background: Pancreatic cancer (PC) is among the most prevalent and deadliest endocrine tumors, yet the mechanisms governing its pathogenesis remain to be fully clarified. While ubiquitin-conjugating enzyme E2C (UBE2C) has been identified as an important oncogene in several cancers, its importance in PC has yet to be established. Methods: UBE2C expression in PC tumor samples and cell lines was examined via quantitative real-time polymerase chain reaction (qRT-PCR), while appropriate commercial kits were used to assess lactate production, ATP generation, and the uptake of glucose. Results: UBE2C was found to be upregulated in PC patient tumors and correlated with poorer survival outcomes. In PC cell lines, the silencing of this gene suppressed the malignant activity of cells, thus supporting its identification as an oncogene in this cancer type. Mechanistically, UBE2C was found to promote enhanced matrix metalloproteinase (MMP) protein expression via activating the PI3K-Akt pathway. Moreover, it was found to bind to the epidermal growth factor receptor (EGFR), stabilizing it and driving additional PI3K-Akt pathway activation. UBE2C knockdown in PC cells impaired their uptake of glucose and their ability to produce lactate and ATP. Conclusions: In conclusion, the results of this study support a role for UBE2C as a driver of metastatic PC progression owing to its ability to bind to EGFR and to induce signaling via the PI3K-Akt pathway.

Increased m6A modification of lncRNA DBH-AS1 suppresses pancreatic cancer growth and gemcitabine resistance via the miR-3163/USP44 axis.

Background: Gemcitabine is among the most commonly utilized chemotherapeutic agents for treating pancreatic cancer (PC), yet patients ultimately develop chemoresistance and thus exhibit a poor prognosis. Long noncoding RNAs (lncRNAs) can function as key regulators of PC progression and may serve as prognostic biomarkers in individuals with gemcitabine-resistant PC. This study sought to explore the role of the lncRNA DBH-AS1 in this oncogenic setting. Methods: Based on public databases and qRT-PCR analyses the expression of lncRNA DBH-AS1 in PC tissues and cell lines. The effects of lncRNA DBH-AS1 on proliferation and gemcitabine resistance were determined by in vitro and in vivo experiments. Luciferase reporter assay and RNA immunoprecipitation (RIP) were carried out to reveal the interaction between lncRNA DBH-AS1, miR-3163 and USP44. Results: We found that PC tissues exhibited DBH-AS1 downregulation that was particularly pronounced in gemcitabine-resistant PC tissues and cells. This DBH-AS1 downregulation was negatively correlated with the malignancy of PC tumors and with patient survival outcomes. Additionally, decreased DBH-AS1 expression in PC was found to be linked to the METTL3-dependent m6A methylation of the lncRNA, with functional analyses revealing that DBH-AS1 was able to suppress the growth of PC cells. Mechanistically, DBH-AS1 was able to increase PC cell sensitivity to gemcitabine by sequestering miR-3163 and thus upregulating USP44 in these tumor cells. Clinically, patient-derived PC tumor xenografts exhibiting high levels of DBH-AS1 expression were found to be responsive to gemcitabine treatment. Conclusions: Overall, these data underscore a key role for DBH-AS1 as a regulator of PC tumor growth and a promising therapeutic target capable of predicting PC patient responsiveness to gemcitabine treatment.

LINC00483 promotes proliferation and metastasis through the miR-19a-3p/TBK1/MAPK axis in pancreatic ductal adenocarcinoma (PDAC).

Background: Long noncoding RNAs (lncRNAs) have been found to promote tumor progression. However, the role of lncRNAs in pancreatic ductal adenocarcinoma (PDAC) requires more investigation. Methods: In this study, microarray was used to measure lncRNA levels in 3 pairs of PDAC tissues. As the highest upregulated lncRNA, LINC00483 was selected for further investigation to determine its functions in PDAC. Quantitative reverse transcription polymerase chain reaction (RT-qPCR) was used to confirm LINC00483 level in PDAC. PDAC cell lines were transfected with short hairpin RNA (shRNA) or microRNA (miRNA). 5-ethynyl-2'-deoxyuridine (EdU) assay, colony formation assay, wound healing assay, transwell assay, and xenograft mouse models were used to evaluate LINC00483 inhibition in vitro and in vivo. Luciferase reporter assay was performed to confirm binding sites of LINC00483 with miR-19a-3p, and miR-19a-3p with TANK-binding kinase 1 (TBK1). Immunohistochemistry (IHC) was performed to evaluate TBK1 and c-myc expression in PDAC tissues. Western blot was used to elucidate the LINC00483/miR-19a-3p/TBK1/mitogen-activated protein kinase (MAPK) axis. Results: Our data showed that LINC00483 was significantly upregulated in PDAC compared to normal tissue. High level of LINC00483 was correlated with advanced clinical stage, tumor invasion and metastasis, and adverse prognosis in PDAC patients. LINC00483 suppression inhibited proliferation and invasion in vitro and tumor development in vivo via modulation of miR-19a-3p expression. Subsequently, we found that miR-19a-3p binds to TBK1 in PDAC and LINC00483 could regulate PDAC cell progression by regulating miR-19a-3p via the TBK1/MAPK pathway. Conclusions: The results of our study suggested that the LINC00483/miR-19a-3p/TBK1/MAPK axis contributed to PDAC progression, which provides a potential therapeutic target for PDAC treatment.

Impact of previous upper/lower abdominal surgery on pancreatic surgical outcomes and complications: a propensity score matching study.

PURPOSE: Pancreatic surgery is a complex operation that has been associated with severe intraoperative and postoperative complications, especially in patients with previous abdominal surgery (PAS). Our study aimed to assess the impact of PAS on pancreatic surgery. METHODS: A total of 1430 patients who underwent pancreatic surgery were included in this retrospective study and classified into the following 3 groups: previous upper abdominal surgery (PUAS) (n = 135); previous lower abdominal surgery (PLAS) (n = 161), and no history of abdominal surgery (non-PAS) (n = 1134). Using propensity score matching (PSM), patients were matched to one another at a 1:1:1 ratio with balanced baseline characteristics. Intraoperative factors, surgical complications, hospital costs, and postoperative hospitalization were collected and compared. RESULTS: A longer operative duration was observed in the PUAS group compared to the non-PAS group (187.54 vs. 150.50 min, p = 0.016). The intraoperative blood loss in the PUAS group was significantly higher (193.68 vs. 150.51 and 156.81 mL, p < 0.05), while the intraoperative plasma transfusion volume was higher in PLAS patients than in non-PAS patients (183.8 vs. 102.7 mL, p = 0.008). Intra-abdominal adhesions in PUAS patients were most severe, and non-PAS patients exhibited significantly lower intra-abdominal adhesion grading (p < 0.001). No significant differences were observed in postoperative complications, postoperative histopathology, postoperative hospitalization, or hospital cost. CONCLUSION: PAS has no significant influences on surgical outcomes, and pancreatic surgery is relatively safe in this patient population. A patient history of PAS may prolong operation duration and increase intraoperative blood loss but has no impact on postoperative complications and does not increase the economic burden.

ELK1 Enhances Pancreatic Cancer Progression Via LGMN and Correlates with Poor Prognosis.

Pancreatic cancer is one of the most lethal cancers and its prognosis is extremely poor. Clarification of molecular mechanisms and identification of prognostic biomarkers are urgently needed. Though we previously found that LGMN was involved in pancreatic carcinoma progression, the upstream regulation of LGMN remains unknown. We used reliable software to search for the potential transcription factors that may be related with LGMN transcription, we found that ELK1 could be a new regulator of LGMN transcription that binded directly to the LGMN promoter. Moreover, knocking down of ELK1 reduced pancreatic cancer cells proliferation, invasion and survival, while LGMN restored the malignancy of pancreatic cancer in vitro and in vivo. Overexpression of ELK1 further increased cancer cells proliferation, invasion and survival. Clinically, ELK1 and LGMN were positively correlated with clinical stage, degree of differentiation and Lymph node infiltration. ELK1 and LGMN were identified as independent prognostic factors for overall survival. The patients with low expression of ELK1/LGMN survived an average of 29.65 months, whereas those with high expression of ELK1/LGMN survived an average of 16.67 months. In conclusive, our results revealed a new mechanism by which ELK1 promoted the progression of pancreatic cancer via LGMN and conferred poor prognosis.

Mutational landscape and potential therapeutic targets for sporadic pancreatic neuroendocrine tumors based on target next-generation sequencing.

Pancreatic neuroendocrine tumor (PNET), a heterogenous type of neoplasm with limited treatment options, is relatively rare and to date, the genetic background has remained to be fully elucidated. The present study aimed to determine the mutational landscape of PNET with and without liver metastasis, as well as its clinical application value for treatment. Fresh tumor tissues were collected from 14 patients with PNET following surgery, 4 of whom had developed liver metastasis. Subsequently, targeted next-generation sequencing of 612 cancer-associated genes and comprehensive analysis were performed on the tumor tissues. The results identified 63 somatic mutations in 53 genes in the 14 patients with PNET, amongst which menin 1 was identified as the most recurrently mutated gene. The analysis also identified several novel recurrently mutated genes, including adrenoceptor alpha 2B, ARVCF delta catenin family member, carbamoyl-phosphate synthetase 2, aspartate transcarbamylase, and dihydroorotase and neuregulin 1. Among the 53 mutated genes, 11 were enriched in the PI3K/AKT signaling pathway (adjusted P=7.12x10-5). In addition, 4 patients with PNET with liver metastasis had distinctly different mutational profiles compared with those without liver metastasis; 13 genes were discovered to be exclusively mutated in the liver metastasis group of the patients with PNET, including ATRX chromatin remodeler, thioredoxin reductase 2, anus kinase 3, ARVCF delta catenin family member, integrin subunit alpha V and RAD50 double strand break repair protein. In addition, two potentially actionable alterations in BRCA2 DNA repair-associated (p.Q548Q) and neurofibromin 1 (p.Q1188X) were identified using the OncoKB database. In conclusion, the present study generated a comprehensive mutational profile of 14 patients with PNET and further described the features of patients with liver metastasis, which highlights potential targets for drug development of PNET.

ACOT4 accumulation via AKT-mediated phosphorylation promotes pancreatic tumourigenesis.

The acyl-CoA thioesterase (ACOT) family catalyses the hydrolysis of acyl-CoA thioesters to their corresponding non-esterified fatty acid and coenzyme A (CoA). Increasing evidence suggests that cancer cells generally have altered lipid metabolism in different aspects. However, the roles of the ACOT family in cancer, especially in pancreatic ductal carcinoma (PDAC), are largely unknown. In the present study, we mined data to determine the clinical significance of all eleven ACOT genes among nine major solid tumour types from TCGA database and found that the expression of ACOT4 in PDAC was negatively correlated with patient survival, establishing ACOT4 as a potential biomarker of PDAC. Depletion of ACOT4 attenuated the proliferation and tumour formation of PDAC cells. Using mass spectrometry, HSPA1A was found to associate with ACOT4. Furthermore, we found that phosphorylation of ACOT4 at S392 by AKT decreased the binding of ACOT4 to HSPA1A, resulting in ACOT4 accumulation. The ACOT4 elevation promotes pancreatic tumourigenesis by producing excessive CoA to support tumour cell metabolism. Thus, our study expands the relationship between AKT signalling and lipid metabolism and establishes a functional role of ACOT4 in PDAC.

Menin Coordinates C/EBPß-Mediated TGF-ß Signaling for Epithelial-Mesenchymal Transition and Growth Inhibition in Pancreatic Cancer.

Menin displays either tumor suppression or promotion functions in a context-dependent manner. Previously, we proposed that Menin acts as a tumor suppressor by inhibiting cell growth in pancreatic ductal adenocarcinoma (PDAC), whereas the relationship between the Menin expression and overall survival rate of PDAC patients has not been completely elucidated, indicating the complexity of Menin functions in PDAC progression. Here, we identify Menin as a promoter of epithelial-mesenchymal transition (EMT), which is largely associated with cell migration or metastasis, with modest activity in cell growth inhibition. Ectopic expression of Menin suppresses the expression of CCAAT/enhancer-binding protein beta (CEBPB) and epithelial-specific genes by histone deacetylation and further enhances the TGF-ß signaling-related EMT process. We also demonstrate that CCAAT/enhancer binding protein (C/EBP) beta (C/EBPß; encoded by CEBPB) acts downstream of Menin and TGF-ß signaling for balancing growth inhibition and EMT, and C/EBPß overexpression could restore the anti-cancer functions of Menin in pancreatic cancer by cooperatively activating CDKN2A/B genes and antagonizing EMT processes. Taken together, our results suggest that Menin functions as an oncogene for cancer metastasis upon C/EBPß depletion or acts as a tumor suppressor by cooperation with C/EBPß to activate CDKN2A transcription.

Ganoderic acid B's influence towards the therapeutic window of trifluoperazine (TFP).

BACKGROUND: Ganoderic acid B is an important bioactive ingredient isolated from Ganoderma lucidum, and exhibits various pharmacological activities. AIMS: To investigate the influence of Ganoderic acid B towards the therapeutic window of trifluoperazine (TFP). METHODS: In vitro human liver microsomes (HLMs) incubation system was used to determine the inhibition of Ganoderic acid B towards the glucuronidation of trifluoperazine (TFP). RESULTS: Ganoderic acid B exerted concentration-dependent inhibition towards the glucuronidation of TFP. Furthermore, Dixon plot was used to determine the inhibition type. The intersection point was located in the second quadrant in Dixon plot, indicating the competitive inhibition of Ganoderic acid B towards TFP glucuronidation. Through fitting the data using competitive nonlinear fitting equation, the inhibition kinetic parameter was calculated to be 56.7 uM. CONCLUSION: All this data indicated the potential influence of Ganoderic acid B-containing herbs towards therapeutic window of TFP. Given that the glucuronidation reaction of TFP is the probe reaction of UGT1A4, the data obtained from the present study also indicated the potential influence of Ganoderic acid-containing herbs towards the therapeutic window of drugs mainly undergoing UGT1A4-mediated metabolism.