Protocol for the characterization of the pancreatic tumor microenvironment using organoid-derived mouse models and single-nuclei RNA sequencing.

Single-nuclei RNA sequencing (snRNA-seq) allows for obtaining gene expression profiles from frozen or hard-to-dissociate tissues at the single-nuclei level. Here, we describe a protocol to obtain snRNA-seq data of pancreatic tumors from orthotopically grafted organoid-derived mouse models. We provide details on the establishment of these mouse models, the isolation of single nuclei from pancreatic tumors, and the analysis of the snRNA-seq datasets. For complete details on the use and execution of this protocol, please refer to Mucciolo et al.1.

EGFR-activated myofibroblasts promote metastasis of pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) has a dismal prognosis. Cancer-associated fibroblasts (CAFs) are recognized potential therapeutic targets, but poor understanding of these heterogeneous cell populations has limited the development of effective treatment strategies. We previously identified transforming growth factor beta (TGF-ß) as a main driver of myofibroblastic CAFs (myCAFs). Here, we show that epidermal growth factor receptor/Erb-B2 receptor (EGFR/ERBB2) signaling is induced by TGF-ß in myCAFs through an autocrine process mediated by amphiregulin. Inhibition of this EGFR/ERBB2-signaling network in PDAC organoid-derived cultures and mouse models differentially impacts distinct CAF subtypes, providing insights into mechanisms underpinning their heterogeneity. Remarkably, EGFR-activated myCAFs promote PDAC metastasis in mice, unmasking functional significance in myCAF heterogeneity. Finally, analyses of other cancer datasets suggest that these processes might operate in other malignancies. These data provide functional relevance to myCAF heterogeneity and identify a candidate target for preventing tumor invasion in PDAC.

A Systematic Review of the safety of non-TNF inhibitor biologic and targeted synthetic drugs in rheumatic disease in pregnancy.

INTRODUCTION: Despite increasing evidence to support safe use of tumour necrosis factor inhibitors (TNFi) and other biologic disease modifying anti-rheumatic drugs (bDMARDs) during pre-conception/pregnancy, there remains a paucity of evidence regarding the safety and compatibility of other non-TNFi and novel targeted synthetic (ts)DMARDs during pre-conception/pregnancy. Therefore, we conducted a systematic review to determine the compatibility of these drugs in pre-conception, during pregnancy and post-partum period. METHOD: Databases including; EMBASE, Pubmed (MEDLINE), and Cochrane were searched up to 23rd October 2020 to find relevant peer-reviewed papers, using keywords including; rheumatic disease, pregnancy, conception/pre-conception, lactation/breastfeeding, childhood and vaccination/infection, and commonly prescribed non-TNFi drugs and tsDMARDs. RESULTS: Our search yielded 1483 papers that were screened independently by two authors, and 109 full-text papers were eligible for final analysis. These studies reported 1291 maternal pregnancies exposed to non-TNFi bDMARDs and tsDMARDs with known outcomes, including 721 live births, 219 spontaneous miscarriages and 27 congenital abnormalities. Paternal exposures in 174 pregnancies had reassuring outcomes. A total of 48 breastfed infants were exposed to non-TNFi bDMARDs and no adverse events reported upon long-term follow-up. Fifteen infants exposed to bDMARDs received normal vaccination regimes, including live vaccines, and had normal developmental outcomes, without any complications or infections. CONCLUSION: Overall, the findings are reassuring and do not suggest a cause for any major concerns or an increased risk of adverse pregnancy outcomes for maternal or paternal exposures to non-TNFi bDMARDs or tsDMARDs. There were no major concerns for breastfeeding exposures to non-TNFi bDMARDs.