Genetic Mutations of Pancreatic Cancer and Genetically Engineered Mouse Models

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy, and the seventh leading cause of cancer-related deaths worldwide. An improved understanding of tumor biology and novel therapeutic discoveries are needed to improve overall survival. Recent multi-gene analysis approaches such as next-generation sequencing have provided useful information on the molecular characterization of pancreatic tumors. Different types of pancreatic cancer and precursor lesions are characterized by specific molecular alterations. Genetically engineered mouse models (GEMMs) of PDAC are useful to understand the roles of altered genes. Most GEMMs are driven by oncogenic Kras, and can recapitulate the histological and molecular hallmarks of human PDAC and comparable precursor lesions. Advanced GEMMs permit the temporally and spatially controlled manipulation of multiple target genes using a dual-recombinase system or CRISPR/Cas9 gene editing. GEMMs that express fluorescent proteins allow cell lineage tracing to follow tumor growth and metastasis to understand the contribution of different cell types in cancer progression. GEMMs are widely used for therapeutic optimization. In this review, we summarize the main molecular alterations found in pancreatic neoplasms, developed GEMMs, and the contribution of GEMMs to the current understanding of PDAC pathobiology. Furthermore, we attempted to modify the categorization of altered driver genes according to the most updated findings.

Awareness About Colorectal Cancer among Young Adults in Poland

Colorectal cancer (CRC) is one of the most predominant malignancies among the adult population. Most cases of CRC develop from non-malignant precursor lesions called adenomas over a long time, which provides an opportunity for prevention with screening programmes. The aim of the present study was to evaluate the knowledge and awareness level concerning colorectal cancer epidemiology, risk factors, symptoms, and prevention among young society in Poland. The knowledge was examined with an anonymous survey between February and March 2021. Statistical analysis was performed and differences were considered significant if the p-value obtained was smaller than the assumed level of significance p ≤ 0.05. Respondents were mostly female, living in a city, with a population of over 500 thousand. The study acquired information that might guide educators about knowledge deficit among young society in Poland. The results confirmed that education, family/friends history of CRC and a place of residence differentiate knowledge and awareness about CRC. They revealed a significant knowledge gap between rural and urban inhabitants as well as a medical and non-medical group.

Recommendations for diagnosing STIC: a systematic review and meta-analysis

Our understanding of the oncogenesis of high-grade serous cancer of the ovary and its precursor lesions, such as serous tubal intraepithelial carcinoma (STIC), has significantly increased over the last decades. Adequate and reproducible diagnosis of these precursor lesions is important. Diagnosing STIC can have prognostic consequences and is an absolute requirement for safely offering alternative risk reducing strategies, such as risk reducing salpingectomy with delayed oophorectomy. However, diagnosing STIC is a challenging task, possessing only moderate reproducibility. In this review and meta-analysis, we look at how pathologists come to a diagnosis of STIC. We performed a literature search identifying 39 studies on risk reducing salpingo-oophorectomy in women with a known BRCA1/2 PV, collectively reporting on 6833 patients. We found a pooled estimated proportion of STIC of 2.8% (95% CI, 2.0–3.7). We focused on reported grossing protocols, morphological criteria, level of pathologist training, and the use of immunohistochemistry. The most commonly mentioned morphological characteristics of STIC are (1) loss of cell polarity, (2) nuclear pleomorphism, (3) high nuclear to cytoplasmic ratio, (4) mitotic activity, (5) pseudostratification, and (6) prominent nucleoli. The difference in reported incidence of STIC between studies who totally embedded all specimens and those who did not was 3.2% (95% CI, 2.3–4.2) versus 1.7% (95% CI, 0.0–6.2) (p 0.24). We provide an overview of diagnostic features and present a framework for arriving at an adequate diagnosis, consisting of the use of the SEE-FIM grossing protocol, evaluation by a subspecialized gynecopathologist, rational use of immunohistochemical staining, and obtaining a second opinion from a colleague.

Dietary Patterns and Severity of Symptom with the Risk of Esophageal Squamous Cell Carcinoma and its Histological Precursor Lesions in China: A Multicenter Cross-Sectional Latent Class Analysis

Background: Dietary patterns and symptoms research among Chinese with esophageal squamous cell carcinoma (ESCC) and its precursor lesions is limited, especially as it relates to multiple food consumption and multiple co-occurring symptoms. The aim of our study was to identify the dietary patterns and severity of symptom classes with the risk of esophageal squamous cell carcinoma and its histological precursor lesions, and develop a risk prediction model for different stages of esophageal disease.Methods: We analyzed data from a multicenter cross-sectional study carried out in ESCC high incidence areas between 2017 and 2018, which included 34,707 individuals aged 40-69 years. Dietary patterns and severity of symptom classes were derived by applying a latent class analysis (LCA). A multiple logistic regression model was used to derive the odds ratio (ORs) and corresponding 95% confidence intervals (CIs) for ESCC and the different stages of esophageal disease according to the dietary patterns and severity of symptom classes identified. We built the risk prediction model by using a nomogram.Results: We identified five dietary patterns and three severity of symptom classes. The dietary patterns were classified as follows: “Healthy”, “Western”, “Lower consumers-combination”, “Medium consumers-combination” and “Higher consumers-combination” patterns based on the intake of foods such as red meat, vegetables and fruits. The severity of symptoms was categorized into “Asymptomatic”, “Mild symptoms” and “Overt symptoms” classes based on health-related symptoms reported by the participants. Compared to the “Healthy” pattern, the other four patterns were all associated with an increased risk of esophageal disease. Similarly, the other two symptom classes present different degrees of increased risk of esophageal disease compared to the “Asymptomatic”. The nomograms reflect the good predictive ability of the model.Conclusion: Among individuals aged 40-69 years in high incidence regions of upper gastrointestinal cancer, the results supplied important epidemiological evidence and given further insights into dietary patterns and symptoms research.

Renalase is a novel tissue and serological biomarker in pancreatic ductal adenocarcinoma

Dysregulated expression of the secretory protein renalase can promote pancreatic ductal adenocarcinoma (PDAC) growth in animal models. We characterized renalase expression in premalignant and malignant PDAC tissue and investigated whether plasma renalase levels corresponded to clinical PDAC characteristics. Renalase immunohistochemistry was used to determine the presence and distribution of renalase in normal pancreas, chronic pancreatitis, PDAC precursor lesions, and PDAC tissues. Associations between pretreatment plasma renalase and PDAC clinical status were assessed in patients with varied clinical stages of PDAC and included tumor characteristics, surgical resection in locally advanced/borderline resectable PDAC, and overall survival. Data were retrospectively obtained and correlated using non-parametric analysis. Little to no renalase was detected by histochemistry in the normal pancreatic head in the absence of abdominal trauma. In chronic pancreatitis, renalase immunoreactivity localized to peri-acinar spindle-shaped cells in some samples. It was also widely present in PDAC precursor lesions and PDAC tissue. Among 240 patients with PDAC, elevated plasma renalase levels were associated with worse tumor characteristics, including greater angiolymphatic invasion (80.0% vs. 58.1%, p = 0.012) and greater node positive disease (76.5% vs. 56.5%, p = 0.024). Overall survival was worse in patients with high plasma renalase levels with median follow-up of 27.70 months vs. 65.03 months (p < 0.001). Renalase levels also predicted whether patients with locally advanced/borderline resectable PDAC underwent resection (AUC 0.674; 95%CI 0.42–0.82, p = 0.04). Overall tissue renalase was increased in both premalignant and malignant PDAC tissues compared to normal pancreas. Elevated plasma renalase levels were associated with advanced tumor characteristics, decreased overall survival, and reduced resectability in patients with locally advanced/borderline resectable PDAC. These studies show that renalase levels are increased in premalignant pancreatic tissues and that its levels in plasma correspond to the clinical behavior of PDAC.

Risk factors for esophageal squamous cell carcinoma and its histological precursor lesions in China: a multicenter cross-sectional study

Background Despite research efforts, the causative factors that contribute to esophageal squamous cell carcinoma (ESCC) in high-risk areas have not yet been understood. In this study, we, therefore, aimed to describe the risk factors associated with ESCC and its precursor lesions. Methods We performed an endoscopic examination of 44,857 individuals aged 40–69 years from five high incidence regions of China in 2017–2018. Participants were classified as 4 groups of normal control, esophagitis, low-grade intraepithelial neoplasia (LGIN) and high-grade intraepithelial neoplasia/esophageal squamous cell carcinoma (HGIN/ESCC) using an unconditional logistic regression determine risk factors. Results We identified 4890 esophagitis, 1874 LGIN and 437 HGIN/ESCC cases. Crude odds ratios (ORs) and adjusted odds ratios were calculated using unconditional logistic regression. Drinking well and surface water, salty diet, and positive family history of cancer were the common risk factors for esophagitis, LGIN and HGIN/ESCC. History of chronic hepatitis/cirrhosis was the greatest risk factor of esophagitis (adjusted OR 2.96, 95%CI 2.52–3.47) and HGIN/ESCC (adjusted OR 1.91, 95%CI 1.03–3.22). Pesticide exposure (adjusted OR 1.20, 95%CI 1.05–1.37) was essential risk factor of LGIN. Conclusions Among individuals aged 40–69 years in high incidence regions of upper gastrointestinal cancer, the results provided important epidemiological evidence for the prevention of different precancerous lesions of ESCC.

The genomic architecture of EBV and infected gastric tissue from precursor lesions to carcinoma

Background Epstein-Barr virus (EBV)-associated gastric carcinomas (EBVaGCs) present unique molecular signatures, but the tumorigenesis of EBVaGCs and the role EBV plays during this process remain poorly understood. Methods We applied whole-exome sequencing, EBV genome sequencing, and whole-genome bisulfite sequencing to multiple samples (n = 123) derived from the same patients (n = 25), which covered saliva samples and different histological stages from morphologically normal epithelial tissues to dysplasia and EBVaGCs. We compared the genomic landscape between EBVaGCs and their precursor lesions and traced the clonal evolution for each patient. We also analyzed genome sequences of EBV from samples of different histological types. Finally, the key molecular events promoting the tumor evolution were demonstrated by MTT, IC50, and colony formation assay in vitro experiments and in vivo xenograft experiments. Results Our analysis revealed increasing mutational burden and EBV load from normal tissues and low-grade dysplasia (LD) to high-grade dysplasia (HD) and EBVaGCs, and oncogenic amplifications occurred late in EBVaGCs. Interestingly, within each patient, EBVaGCs and HDs were monoclonal and harbored single-strain-originated EBV, but saliva or normal tissues/LDs had different EBV strains from that in EBVaGCs. Compared with precursor lesions, tumor cells showed incremental methylation in promotor regions, whereas EBV presented consistent hypermethylation. Dominant alterations targeting the PI3K-Akt and Wnt pathways were found in EBV-infected cells. The combinational inhibition of these two pathways in EBV-positive tumor cells confirmed their synergistic function. Conclusions We portrayed the (epi) genomic evolution process of EBVaGCs, revealed the extensive genomic diversity of EBV between tumors and normal tissue sites, and demonstrated the synergistic activation of the PI3K and Wnt pathways in EBVaGCs, offering a new potential treatment strategy for this disease.