Recent Articles on Pancreatobiliary #Pathology – 2020-10-13

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


  • Targeting DNA Damage Response and Replication Stress in Pancreatic Cancer

Gastroenterology 2020 Oct;():

PubMed: https://www.ncbi.nlm.nih.gov/pubmed/?term=33039466

BACKGROUND AND AIMS: Continuing recalcitrance to therapy cements pancreatic cancer (PC) as the most lethal malignancy, which is set to become the second leading cause of cancer death in our society. The study aim was to investigate the association between DNA damage response (DDR), replication stress and novel therapeutic response in PC to develop a biomarker driven therapeutic strategy targeting DDR and replication stress in PC.
METHODS: We interrogated the transcriptome, genome, proteome and functional characteristics of 61 novel PC patient-derived cell lines to define novel therapeutic strategies targeting DDR and replication stress. Validation was done in patient derived xenografts and human PC organoids.
RESULTS: Patient-derived cell lines faithfully recapitulate the epithelial component of pancreatic tumors including previously described molecular subtypes. Biomarkers of DDR deficiency, including a novel signature of homologous recombination deficiency, co-segregates with response to platinum (P < 0.001) and PARP inhibitor therapy (P < 0.001) in vitro and in vivo. We generated a novel signature of replication stress with which predicts response to ATR (P < 0.018) and WEE1 inhibitor (P < 0.029) treatment in both cell lines and human PC organoids. Replication stress was enriched in the squamous subtype of PC (P < 0.001) but not associated with DDR deficiency.
CONCLUSIONS: Replication stress and DDR deficiency are independent of each other, creating opportunities for therapy in DDR proficient PC, and post-platinum therapy.

doi: https://doi.org/10.1053/j.gastro.2020.09.043



  • Focal parenchymal atrophy of pancreas: An important sign of underlying high-grade pancreatic intraepithelial neoplasia without invasive carcinoma, i.e., carcinoma in situ

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

PubMed: https://www.ncbi.nlm.nih.gov/pubmed/?term=33039293

OBJECTIVES: Diagnosing high-grade intraepithelial neoplasia without invasion, traditionally referred to as carcinoma in situ (CIS), is essential for improving prognosis. We examined the imaging findings of patients with and without CIS to identify significant aspects for the diagnosis of CIS.
METHODS: Forty-six patients strongly suspected of early pancreatic cancer without nodule on imaging (CIS group, n = 27; non-malignant group, n = 19) were retrospectively evaluated according to ten factors of computed tomography/magnetic resonance imaging (CT/MRI), endoscopic ultrasonography (EUS), and endoscopic retrograde cholangiopancreatography (ERCP) using hierarchical cluster and univariate analyses.
RESULTS: Two clusters were formed by hierarchical cluster analysis. One cluster consisted of 83.3% CIS cases with similar image findings such as focal pancreatic parenchymal atrophy (FPPA) on CT/MRI, main pancreatic duct (MPD) stricture surrounded by hypoechoic areas on EUS, and MPD stricture with upstream MPD dilation on ERCP. On univariate analysis, the CIS and non-malignant groups had FPPA on CT/MRI in 15 (55.6%) and 3 (15.8%) cases (p = 0.013), and MPD stricture surrounded by hypoechoic areas on EUS in 20 (74.1%) and 4 (21.1%) cases (p = 0.001), respectively. MPD stricture surrounded by hypoechoic areas was observed in 80% (12/15) of CIS cases with FPPA on CT/MRI and correlated with FPPA. Moreover, FPPA and MPD stricture surrounded by hypoechoic areas had histopathologically observed fibrosis or fat replacement due to pancreatic parenchymal atrophy.
CONCLUSIONS: FPPA and MPD stricture surrounded by hypoechoic areas are significant findings for the diagnosis of CIS.

doi: https://doi.org/10.1016/j.pan.2020.09.020



  • Par-4 activation restrains EMT-induced chemoresistance in PDAC by attenuating MDM-2

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

PubMed: https://www.ncbi.nlm.nih.gov/pubmed/?term=33039292

BACKGROUND: We recently reported prostate apoptosis response 4 (Par-4), a potential tumor suppressor protein restrains epithelial-mesenchymal transition (EMT) properties and promotes mesenchymal-epithelial transition (MET) in invasive cancer cells by repressing Twist-1 promoter activity. Here, we demonstrate that genetic as well as pharmacological modulation of Par-4 by NGD16 (a small molecule antimetastatic agent), limits EMT-induced chemoresistance in aggressive cancer cells by suppressing MDM-2, a downstream effector of Twist-1.
METHODS: Matrigel invasion assay, gelatin degradation assay, cell scattering assay, MTT assay and colony formation assay were used to study the proliferation and migration abilities of invasive cancer cells. Immunoblotting, immunocytochemistry, and immunoprecipitation analysis were utilized for determining protein expression and protein-protein interaction. 4T1 aggressive mouse carcinoma model was employed to evaluate tumor growth and lung metastasis.
RESULTS: Treatment of gemcitabine (nucleoside analogue anticancer agent) to pancreatic cancer (Panc-1, MiaPaca-2) and breast cancer (MDA-MB-231) cells amplified MDM-2 expression along with increase in EMT properties. Conversely, NGD16 boosted expression of tumor suppressor Par-4 and inhibited invasion and migration abilities of these cells. Moreover, induction of Par-4 effectively diminished MDM-2 along with pro-EMT markers, whereas, augmented the expression of epithelial markers. Furthermore, siRNA-mediated silencing of Par-4 divulged that NGD16 exerts its EMT inhibitory effects in a Par-4-dependent manner. Mechanistically, Par-4 activation provokes p53 by disrupting MDM-2-p53 interaction, which restored epithelial characteristics in cancer cells. Additionally, partial knockdown of MDM-2 through siRNA pronounced the anti-proliferative and anti-invasive effects of NGD16. Finally, NGD16 efficiently inhibited tumor growth and lung metastasis in mouse mammary carcinoma model without showing any undesirable effects.
CONCLUSION: Our findings unveil Par-4 as a key therapeutic target and NGD16 (the pharmacological modulator of Par-4) are potential tools to suppress EMT and associated chemoresistance, which could be exploited clinically for the treatment of aggressive cancers.

doi: https://doi.org/10.1016/j.pan.2020.09.021


New GallBladder Articles

Today there is no new Gallbladder Article.

New BileDuct Articles


  • Stratification of Postoperative Prognosis by Invasive Tumor Thickness in Perihilar Cholangiocarcinoma

Annals of surgical oncology 2020 Oct;():

PubMed: https://www.ncbi.nlm.nih.gov/pubmed/?term=33040247

BACKGROUND: The pathological tumor classification of distal cholangiocarcinoma in the American Joint Committee on Cancer (AJCC) Cancer Staging Manual 8th edition is based on invasive depth, whereas that of perihilar cholangiocarcinoma (PHCC) continues to be layer-based. We aimed to clarify whether invasive depth measurement based on invasive tumor thickness (ITT) could help determine postoperative prognosis in patients with PHCC.
METHODS: We enrolled 184 patients with PHCC who underwent hepatectomy plus extrahepatic bile duct resection or hepatopancreatoduodenectomy with curative intent. ITT was measured using simple definitions according to the sectioning direction or gross tumor pattern.
RESULTS: The median ITT was 5.8 mm (range 0.7-15.5). Using the recursive partitioning technique, ITT was classified into grades A (ITT < 2 mm, n = 9), B (2 mm ≤ ITT < 5 mm, n = 68), C (5 mm ≤ ITT < 11 mm, n = 81), and D (11 mm < ITT, n = 26). The median survival times (MSTs) in patients with grade B, C, or D were 90.8, 44.6, and 21.1 months, respectively (patients with grade A did not reach the MST). There were significant differences in postoperative prognosis between ITT grades (A vs. B, p = 0.027; B vs. C, p < 0.001; C vs. D, p = 0.004). Through multivariate analysis, regional node metastasis, invasive carcinoma at the resected margin, and ITT grade were determined as independent prognostic factors.
CONCLUSION: ITT could be measured using simple methods and may be used to stratify postoperative prognosis in patients with PHCC.

doi: https://doi.org/10.1245/s10434-020-09135-9


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/