Recent Articles on Pancreatobiliary #Pathology – 2020-08-24

These are the recent articles on Pancreatobiliary Pathology:

To see all journal watch articles please visit: http://pbpath.org/journal-watch-upcoming-issue/

New Pancreas Articles


  • The occurrence of prion protein in surgically resected pancreatic adenocarcinoma

Pancreatology : official journal of the International Association of Pancreatology (IAP) … [et al.] 2020 Aug;():

PubMed: https://www.ncbi.nlm.nih.gov/pubmed/?term=32828686

BACKGROUND: Among the several new targets for the comprehension of the biology of pancreatic ductal adenocarcinoma (PDAC), Prion proteins (PrPc) deserve particular mention, since they share a marked neurotropism. Actually, PrPc could have also a role in tumorigenesis, as recently demonstrated. However, only few in vitro studies in cell cultures showed the occurrence of PrPc in PDAC cells. We aim to evaluate the presence of PrPc in vivo in PDAC tissues as a potential new biomarker.
METHODS: Samples from tumors of 23 patients undergone pancreatic resections from July 2018 to May 2020 at our institution were collected and analyzed. Immunohistochemistry and western blotting of PDAC tissues were compared with control tissues. Immunohistochemistry was used also to evaluate the localization of PrPc and of CD155, a tumoral stem-cell marker.
RESULTS: All cases were moderately differentiated PDAC, with perineural invasion (PNI) in 19/23 cases (83%). According to western-blot analysis, PrPc was markedly expressed in PDAC tissues (273.5 ± 44.63 OD) respect to controls (100 ± 28.35 OD, p = 0.0018). Immunohistochemistry confirmed these findings, with higher linear staining of PrPc in PDAC ducts (127.145 ± 7.56 μm vs 75.21 ± 5.01 μm, p < 0.0001). PrPc and CD155 exactly overlapped in ductal tumoral cells, highlighting the possible relationship of PrPc with cancer stemness. Finally, PrPc expression related with cancer stage and there was a potential correspondence with PNI.
CONCLUSIONS: Our work provides evidence for increased levels of PrPc in PDAC. This might contribute to cancer aggressiveness and provides a potentially new biomarker. Work is in progress to decipher clinical implications.

doi: https://doi.org/10.1016/j.pan.2020.08.004



  • Whole-exome Sequencing Reveals New Potential Susceptibility Genes for Japanese Familial Pancreatic Cancer

Annals of surgery 2020 Aug;():

PubMed: https://www.ncbi.nlm.nih.gov/pubmed/?term=32826389

OBJECTIVE: The primary objective of this study was to identify novel genes that predispose people in the Japanese population to FPC.
SUMMARY OF BACKGROUND DATA: Familial history of pancreatic cancer is an important risk factor but, to date, few genes predisposing individuals to increased risk of developing FPC have been identified.
METHODS: We performed whole-exome sequencing of germline DNA from 81 Japanese FPC patients. We also investigated somatic gene alterations in 21 matched tumor tissues through whole-exome sequencing and copy number analysis.
RESULTS: Our germline variants identified previously known FPC susceptibility genes such as ATM and BRCA2, and several novel tumor suppressor genes with potentially deleterious variants for FPC. Interestingly, somatic whole-exome analysis demonstrated that most tumor samples with suspicious loss of heterozygosity of candidate genes were KRAS wild-types, implying that these cases may not have required KRAS activation as a driver event for carcinogenesis.
CONCLUSIONS: Our findings indicate that FPC patients harbor potentially deleterious causative germline variants in tumor suppressor genes, which are known to acquire somatic mutations in pancreatic cancer, and that somatic loss of heterozygosity of some FPC susceptibility genes may contribute to the development of FPC in the absence of somatic KRAS-activating mutation. Genetic testing for a wider variety of FPC-predisposition genes could provide better screening approach for high-risk groups of pancreatic cancer.

doi: https://doi.org/10.1097/SLA.0000000000004213



  • Reciprocal regulation of pancreatic ductal adenocarcinoma growth and molecular subtype by HNF4�� and SIX1/4

Gut 2020 Aug;():

PubMed: https://www.ncbi.nlm.nih.gov/pubmed/?term=32826305

OBJECTIVE: Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with a 5-year survival of less than 5%. Transcriptomic analysis has identified two clinically relevant molecular subtypes of PDAC: classical and basal-like. The classical subtype is characterised by a more favourable prognosis and better response to chemotherapy than the basal-like subtype. The classical subtype also expresses higher levels of lineage specifiers that regulate endodermal differentiation, including the nuclear receptor hepatocyte nuclear factor 4 α (HNF4α). The objective of this study is to evaluate the role of HNF4α, SIX4 and SIX1 in regulating the growth and molecular subtype of PDAC.
DESIGN: We manipulate the expression of HNF4α, SIX4 and SIX1 in multiple in vitro and in vivo PDAC models. We determine the consequences of manipulating these genes on PDAC growth, differentiation and molecular subtype using functional assays, gene expression analysis and cross-species comparisons with human datasets.
RESULTS: We show that HNF4α restrains tumour growth and drives tumour cells toward an epithelial identity. Gene expression analysis of murine models and human tumours shows that HNF4α activates expression of genes associated with the classical subtype. HNF4α also directly represses SIX4 and SIX1, two mesodermal/neuronal lineage specifiers expressed in the basal-like subtype. Finally, SIX4 and SIX1 drive proliferation and regulate differentiation in HNF4α-negative PDAC.
CONCLUSION: Our data show that HNF4α regulates the growth and molecular subtype of PDAC by multiple mechanisms, including activation of the classical gene expression programme and repression of SIX4 and SIX1, which may represent novel dependencies of the basal-like subtype.

doi: https://doi.org/10.1136/gutjnl-2020-321316



  • Prehabilitation prior to surgery for pancreatic cancer: A systematic review

Pancreatology : official journal of the International Association of Pancreatology (IAP) … [et al.] 2020 Aug;():

PubMed: https://www.ncbi.nlm.nih.gov/pubmed/?term=32826168

INTRODUCTION: Prehabilitation aims to improve fitness and outcomes of patients undergoing major surgery. This systematic review aimed to appraise current available evidence regarding the role of prehabilitation in patients undergoing oncological pancreatic resection.
METHODS: A systematic literature search of PUBMED, MEDLINE, EMBASE databases identified articles describing prehabilitation programmes before pancreatic resection for malignancy. Data collected included timing of prehabilitation, programme type, duration, adherence and post-operative outcome reporting.
RESULTS: Six studies, including 193 patients were included in the final analysis. Three studies included patients undergoing neoadjuvant therapy followed by resection and 3 studies included patients undergoing upfront resection. Time from diagnosis to surgery ranged between 2 and 22 weeks across all studies. Two studies reported a professionally supervised exercise programme, and four described unsupervised programmes. Exercise programmes varied from 5 days to 6 months in duration. Adherence to exercise programmes was better with supervised programmes (99% reaching weekly activity goal vs 85%) and patients not undergoing neoadjuvant therapy (90% reaching weekly activity goal vs 82%). All studies reported improvement in muscle mass or markers of muscle function following prehabilitation. Two studies reported the impact of Prehabilitation on postoperative outcomes and Prehabilitation was associated with lower delayed gastric emptying and a shorter hospital stay with no impact on other postoperative outcomes.
CONCLUSION: Early evidence demonstrates that Prehabilitation programmes may improve postoperative outcomes following pancreatic surgery. However current Prehabilitaton programmes for patients undergoing pancreatic resection report diverse exercise regimens with no consensus regarding timing or length of Prehabilitation, warranting a need for standardisation of Prehabilitation programmes in pancreatic surgery.

doi: https://doi.org/10.1016/j.pan.2020.07.411


New GallBladder Articles

Today there is no new Gallbladder Article.

New BileDuct Articles

Today there is no new Bile Duct Article.

New Ampulla Articles

Today there is no new Ampulla Article.

To see all journal watch articles please visit: http://pbpath.org/journal-watch-upcoming-issue/