Left Amyand’s hernia with inflamed appendix and sealed of perforated caecum an unusual case

Amyand’s hernia is defined as the hernia with appendix normal, inflamed or perforated as content. 1% of inguinal hernias are Amyand’s and amongst them 0.1% contains inflamed appendix. Commonly encountered on right size due to anatomical position of appendix. Left Amyand’s is rare and associated with intestinal malrotation, situs invertus and mobile caecum. Here, we presented an interesting case of left irreducible hernia in 70 years old gentleman with no signs of acute obstruction or strangulation, patient underwent emergency laparotomy in which hernial sac contents were inflamed ileal loop, inflamed appendix and perforated caecum in 70 years old man is rare presentation and not reported in any literature as per our knowledge. Resection of inflamed bowel loop with ceacum done along with ileo ascending anastomosis with primary tissue repair done. Post-operative period was uneventful. Hernia sac contents are most of the time surprising and their management sometimes differ according to the content. Appendix in hernia sac is found in 1% of all hernia but lack of facility for the pre-operative diagnosis and varied presentation it is challenging to diagnose and operate accordingly.

Gastrointestinal cancer organoids—applications in basic and translational cancer research

Cancer is a major health problem and a leading cause of death worldwide. Early cancer detection and continuous changes in treatment strategies have improved overall patient survival. The recent development of targeted drugs offers new opportunities for personalized cancer treatment. Nevertheless, individualized treatment is accompanied by the need for biomarkers predicting the response of a patient to a certain drug. One of the most promising breakthroughs in recent years that might help to overcome this problem is the organoid technology. Organoid cultures exhibit self-renewal capacity, self-organization, and long-term proliferation, while recapitulating many aspects of their primary tissue. Generated patient-derived organoid (PDO) libraries constitute “living” biobanks, allowing the in-depth analysis of tissue function, development, tumor initiation, and cancer pathobiology. Organoids can be derived from all gastrointestinal tissues, including esophageal, gastric, liver, pancreatic, small intestinal and colorectal tissues, and cancers of these tissues. PDOs are amenable to various techniques, including sequencing analyses, drug screening, targeted therapy testing, tumor microenvironment studies, and genetic engineering capabilities. In this review, we discuss the different applications of gastrointestinal organoids in basic cancer biology and clinical translation.

Abstract P436: Modeling Genetic Dilated Cardiomyopathy Using Induced Pluripotent Stem Cell-derived Engineered Heart Tissues For Precision Medicine

Recent advancement of human induced pluripotent stem cell-derived cardiomyocyte (hiPSC-CM) technologies has opened the door to next-generation modeling of human cardiac biology and disease. Not only does this alleviate the need for human primary tissue and compensate for the well documented deficiencies of rodent models for cardiovascular disease, but these technologies may lead to the identification of better candidates for clinical development. Unfortunately, most current 2D hiPSC-CM models lack the biochemical, mechanical, and electrical feedback that cardiomyocytes endure in a multi-cellular aligned tissue, which limits their translatability into clinical settings. To address this, we incorporated hiPSC-CMs modeling various genetic dilated cardiomyopathies (DCM) into 3D engineered heart tissues (EHTs). Here, we show these models develop distinguishable contractile defects recapitulating hallmarks of DCM when compared to biologically relevant controls. Moreover, this distinct phenotype is quantitative, reproducible, and demonstrates utility for drug discovery. As this innovative technology continues to develop, EHTs are on the forefront of emerging biomimetic assays that can be used to prevent drug attrition in the late stages of drug development.

Intestinal organoids expose heterogeneity in SARS-CoV-2 susceptibility

Organoids generated from primary human specimens facilitate investigation of the intestinal barrier by recreating the complex cellular composition of the epithelium. Although the significance remains unclear, intestinal organoid lines display heterogeneity in their growth and morphology. We hypothesized that organoids will also display variability in the degree to which they are susceptible to infectious agents. Using SARS-CoV-2 as a model, we found orders of magnitude differences in the amount of SARS-CoV-2 recovered from small intestinal and colonic organoids generated from different donors. SARS-CoV-2 burden did not correlate with demographic or clinical features associated with donors, but rather reflected the expression level of the virus receptor ACE2. Remarkably, organoid ACE2 transcript levels matched the amount of ACE2 detected in primary tissue from the same individual, indicating that certain properties of the intestinal epithelium are retained during ex vivo differentiation. Longitudinal transcriptomics of organoids identified a delayed yet robust interferon signature, the magnitude of which corresponded to the degree of SARS-CoV-2 infection. These results suggest that intestinal organoids display substantial heterogeneity in their ability to support viral infections and can potentially inform mechanisms behind interindividual differences in susceptibility to infectious disease.

The Effect of Genomic DNA Contamination on the Detection of Circulating Long Non-Coding RNAs: The Paradigm of MALAT1

The presence of contaminating gDNA in RNA preparations is a frequent cause of false positives in RT-PCR-based analysis. However, in some cases, this cannot be avoided, especially when there are no exons–intron junctions in the lncRNA sequences. Due to the lack of exons in few of long noncoding RNAs (lncRNAs) and the lack of DNAse treatment step in most studies reported so far, serious questions are raised about the specificity of lncRNA detection and the potential of reporting false-positive results. We hypothesized that minute amounts of gDNA usually co-extracted with RNA could give false-positive signals since primers would specifically bind to gDNA due to the lack of junction. In the current study, we evaluated the effect of gDNA and other forms of DNA like extrachromosomal circular DNAs (eccDNAs) contamination and the importance of including a DNAse treatment step on lncRNAsexpression.As a model, we have chosen as one of the most widely studied lncRNAs in cancer namely MALAT1, which lacks exons. When we tested this hypothesis in plasma and primary tissue samples from NSCLC patients, our findings clearly indicated that results on MALAT1 expression are highly affected by the presence of DNA contamination and that the DNAse treatment step is absolutely necessary to avoid false positive results.

Ki67 and PR to predict sensitivity of palbociclib: A real-world study.

e13032 Background: Palbociclib combined with endocrine therapy are approved as a front-line treatment for hormone receptor (HR)-positive, HER2-negative advanced breast cancer (ABC). A key challenge remains to uncover biomarkers to identify those patients who may benefit from palbociclib treatment. Methods: We retrospectively analyzed the values of Ki67 and progesterone receptor (PR), detected by immunohistochemistry, in 81 ABC patients with palbociclib and hormone therapy treatment, and evaluated the impact on progression-free survival (PFS). Results: In total population, women with Ki67≥14% had marginal significant shorter PFS than those with Ki67<14%. Patients with Ki67≥30% had significant shorter PFS than those with Ki67<30% ( P=0.048). While PR≥ 20% was associated with longer PFS. And what’s more, the change trend of Ki67 or PR from primary tissue to metastatic lesions was related to PFS. In regard with hormone therapy subgroup, there were significant association between Ki67 and PR levels and PFS in aromatase inhibitors (AIs) subgroup. Patients with Ki67≥14% or Ki67≥ 30% had shorter PFS than those with Ki67<14% or Ki67<30%, respectively ( P=0.024, P <0.001). Additionally, the change trend of Ki67 or PR from primary tissue to metastatic lesions was related to PFS. When both Ki67 and PR are considered, there were significant differences between different cohort. Compared with those with Ki67≥14% and PR <20%, patients with Ki67<14% and PR≥20% had significant longer PFS. In addition, patients with Ki67<30% and PR≥20% had significant longer PFS than those with Ki67≥30% and PR<20%. Besides, in AIs cohort, patients with Ki67<14% and PR≥20% had significant longer PFS than those with Ki67≥14% and PR <20%. Women with Ki67<30% and PR≥20% had significant longer PFS than those with Ki67≥30% and PR<20%. Conclusions: The present study indicates that both Ki67 and PR have a greater impact on palbociclib and hormone therapy and may help selecting a more effective partner of palbociclib.

Concordance of DNA damage repair (DDR) gene mutations in paired primary and metastatic prostate cancer (PC) samples.

5020 Background: Mutations in DDR genes represent actionable alterations that can be used to guide precision medicine strategies in men with advanced PC. However, acquisition of contemporary tissue samples for advanced molecular testing can be a barrier to deploying precision medicine approaches. We hypothesized that most DDR alterations represent early truncal events in PC and that archival primary tissue would faithfully reflect mutations found in cell-free circulating tumor (ctDNA) and/or metastatic tissue. Methods: Patients were included in this study if a DDR pathway mutation was detected in metastatic tissue or ctDNA and primary tissue sequencing was available for comparison. Sequencing data from three cohorts were analyzed: 1) FoundationOne, 2) University of Washington (UW-OncoPlex or SU2C/PCF International Dream Team sequencing pipelines) and 3) University of Washington rapid autopsy series. Only pathogenic somatic mutations were included and we required ≥30 days between primary tumor tissue and ctDNA/tumor tissue acquisition. Clonal hematopoiesis of indeterminant potential (CHIP) and germline events were adjudicated by an expert molecular pathologist and excluded. Variants detected only in plasma were considered likely to be CHIP or low subclones if the variant fraction was <1% and/or >5-fold less than the estimate tumor content in plasma. Results: Paired primary and ctDNA/metastatic samples were sequenced from 72 individuals with known DDR alterations. After excluding ctDNA cases where only CHIP (N=13) and/or germline events (N=7) were observed, 51 subjects remained and were included in the final analysis. The median time from acquisition of primary tissue to acquisition of ctDNA or tumor tissue was 52 mos (range: 1 – 193 mos). Concordance in DDR genes across samples was 86% (95% CI: 74-93%). Rates of concordance between metastatic-primary and ctDNA-primary pairs were similar when CHIP cases were excluded (87% and 85%, respectively). BRCA2 reversion mutations associated with resistance to PARP inhibitors and platinum chemotherapy were detected in ctDNA from two subjects. Conclusions: These data provide evidence that primary prostate tissue accurately reflect the mutational status of actionable DDR genes in men with metastatic PC, supporting the hypothesis that DDR alterations are early truncal events. After excluding likely CHIP events, ctDNA profiling accurately captured these truncal DDR mutations, while also detecting reversion alterations that may suggest potential resistance mechanisms.[Table: see text]

Ulcerative colitis immune cell landscapes and differentially expressed gene signatures determine novel regulators and predict clinical response to biologic therapy

The heterogeneous pathobiology underlying Ulcerative Colitis (UC) is not fully understood. Using publicly available transcriptomes from adult UC patients, we identified the immune cell landscape, molecular pathways, and differentially expressed genes (DEGs) across patient cohorts and their association with treatment outcomes. The global immune cell landscape of UC tissue included increased neutrophils, T CD4 memory activated cells, active dendritic cells (DC), and M0 macrophages, as well as reduced trends in T CD8, Tregs, B memory, resting DC, and M2 macrophages. Pathway analysis of DEGs across UC cohorts demonstrated activated bacterial, inflammatory, growth, and cellular signaling. We identified a specific transcriptional signature of one hundred DEGs (UC100) that distinctly separated UC inflamed from uninflamed transcriptomes. Several UC100 DEGs, with unidentified roles in UC, were validated in primary tissue. Additionally, non-responders to anti-TNFα and anti-α4β7 therapy displayed distinct profiles of immune cells and pathways pertaining to inflammation, growth, and metabolism. We identified twenty resistant DEGs in UC non-responders to both therapies of which four had significant predictive power to treatment outcome. We demonstrated the global immune landscape and pathways in UC tissue, highlighting a unique UC signature across cohorts and a UC resistant signature with predictive performance to biologic therapy outcome.