Project description:BackgroundPrimary gastric linitis plastica (GLP) is a distinct phenotype of gastric cancer with poor survival. Comprehensive molecular profiles and putative therapeutic targets of GLP remain undetermined.MethodsWe subjected 10 tumor-normal tissue pairs to whole exome sequencing (WES) and whole transcriptome sequencing (WTS). 10 tumor samples were all GLP which involves 100% of the gastric wall macroscopically. TCGA data were compared to generate the top mutated genes and the overexpressed genes in GLP.ResultsOur results reveal that GLP has distinctive genomic and transcriptomic features, dysfunction in the Hippo pathway is likely to be a key step during GLP development. 6 genes were identified as significantly highly mutated genes in GLP, including AOX1, ANKRD36C, CPXM1, PTPN14, RPAP1, and DCDC1). MUC6, as a previously identified gastric cancer driver gene, has a high mutation rate (20%) in GLP. 20% of patients in our GLP cohort had CDH1 mutations, while none had RHOA mutations. GLP exhibits high immunodeficiency and low AMPK pathway activity. Our WTS results showed that 3 PI3K-AKT pathway-related genes (PIK3R2, AKT3, and IGF1) were significantly up-regulated in GLP. Two genes were identified using immunohistochemistry (IHC), IGF2BP3 and MUC16, which specifically expressed in diffuse-type-related gastric cancer cell lines, and its knockdown inhibits PI3K-AKT pathway activity.ConclusionsWe provide the first integrative genomic and transcriptomic profiles of GLP, which may facilitate its diagnosis, prognosis, and treatment.
Project description:Gastric linitis plastica (GLP) is a descriptive term but lacks a quantitative definition. Several relatively quantitative criteria had been proposed, such as tumor involving a limit of one-third or two-thirds of the gastric surface. However, these criteria needed doctors to subjectively judge tumor infiltration area, which made diagnosis difficult to be objective and reproducible. This study aimed to propose a quantitative diagnostic criterion for distinguishing GLP. We performed a retrospective cohort study of 2,907 patients with Borrmann III and IV gastric cancer (GC) who underwent gastrectomy between 2011 and 2018 in our center. The Kaplan-Meier curves showed that patients with an observed tumor size more than 8 cm had obviously lower overall survival (OS) and disease-free survival (DFS) rates than those with a size less than 8 cm(p < 0.001; p < 0.001). However, there was no significantly different prognosis of patients with tumor sizes between more than 8 cm and more than 10 cm (p = 0.248; p = 0.534). Moreover, patients with tumor sizes greater than 8 cm more presented with advanced stage and had extremely poor 3-year OS and DFS (31.4%; 29.3%), with a stronger propensity toward peritoneal metastasis. Therefore, we considered patients' observed tumor size more than 8 cm as a critical value for distinguishing the prognosis of Borrmann III and IV GC. Furthermore, we proposed an observed tumor size more than 8 cm as a quantitative diagnostic criterion for GLP on the premise of satisfying the originally descriptive and pathological definition regardless of Borrmann type.
Project description:For gastric lesions in a patient with a history of breast cancer, it is essential to distinguish between primary gastric cancer and gastric metastasis from breast cancer. However, gastric metastasis from breast cancer often mimics primary linitis plastica, and histological diagnosis may be difficult with conventional endoscopic biopsies. Herein, we describe the case of a 75-year-old woman who presented at our hospital with epigastralgia and vomiting. She had a history of mastectomy for carcinoma of the right breast and had received hormone therapy as adjuvant therapy. Computed tomography at arrival showed thickening of the gastric wall at the antrum and peritoneal dissemination. Esophagogastroduodenoscopy showed mucosal swelling of the antrum and stenosis of the pylorus, and histological diagnosis failed with conventional endoscopic biopsies. Endoscopic ultrasound-guided fine-needle biopsy using a Franseen needle was performed, and a diagnosis of gastric metastasis from breast cancer was made. She received hormone therapy and chemotherapy after deployment of a metallic stent for gastric outlet obstruction. To the best of our knowledge, this is the first case of gastric metastasis from breast cancer diagnosed using endoscopic ultrasound-guided fine-needle biopsy.
Project description:Chronic exposure to hypoxia causes pulmonary hypertension and pulmonary arterial remodeling. Although the exact mechanisms of this remodeling are unclear, there is evidence that it is dependent on hemodynamic stress, rather than on hypoxia alone. Pulmonary supernumerary arteries experience low hemodynamic stress as a consequence of reduced perfusion due to 90° branching angles, small diameters, and "valve-like" structures at their orifices. We investigated whether or not intra-acinar supernumerary arteries undergo structural remodeling during the moderate pulmonary hypertension induced by chronic hypoxia. Rats were exposed to either normoxia or hypoxia for 6 weeks. The chronically hypoxic rats developed pulmonary hypertension. For both groups, pulmonary arteries were selectively filled with barium-gelatin mixture, and the wall thickness of intra-acinar pulmonary arteries was measured in histological samples. Only thin-walled arteries were observed in normoxic lungs. In hypertensive lungs, we found both thin- and thick-walled pulmonary arteries with similar diameters. Disproportionate degrees of arterial wall thickening between parent and daughter branches were observed with supernumerary branching patterns. While parent arteries developed significant wall thickening, their supernumerary branches did not. Thus, chronic hypoxia-induced pulmonary hypertension did not cause wall thickening of intra-acinar pulmonary supernumerary arteries. These findings are consistent with the idea that hemodynamic stress, rather than hypoxia alone, is the cause of structural remodeling during chronic exposure to hypoxia.
Project description:A 54-year-old man had previously undergone curative sigmoidectomy for poorly differentiated adenocarcinoma with a signet-ring cell component of the sigmoid colon, which was characterized morphologically by stenosis and inelasticity of the colon (linitis plastica). Six weeks after surgery, the patient developed stenosis of the right ureter. Disseminated sigmoid cancer was suspected, and chemotherapy was started. Nine months after initiation of chemotherapy, obstructive jaundice was observed which was due to stenosis of the distal bile duct (BD). Although computed tomography showed no evident metastatic lesion that could cause the stenosis, swelling of the entire pancreas was evident compared to that of 11 months earlier. Endoscopic ultrasound (EUS) also did not detect any focal masses in the head of the pancreas, although there was a diffuse hypoechoic change in the entire pancreas. Histopathology of the stenotic BD and biopsy specimen from the head of the pancreas showed no malignant cells. Two months after the initial endoscopic bile duct drainage, the patient was admitted again for epigastric pain. A second EUS fine needle aspiration (EUS-FNA) of the head of the pancreas was performed and showed poorly differentiated carcinoma with some signet-ring cells. This finding provided histological confirmation of a disseminated pancreatic lesion of the previously resected linitis plastica of the sigmoid colon. This is a rare case of disseminated pancreatic lesion from primary linitis plastica of the colon diagnosed by EUS-FNA.
Project description:OBJECTIVE: In this article we present a simplified algorithm-based approach to the thickening of the small and large bowel wall detected on routine computed tomography (CT) of the abdomen. BACKGROUND: Thickening of the small or large bowel wall may be caused by neoplastic, inflammatory, infectious, or ischaemic conditions. First, distinction should be made between focal and segmental or diffuse wall thickening. In cases of focal thickening further analysis of the wall symmetry and perienteric anomalies allows distinguishing between neoplasms and inflammatory conditions. In cases of segmental or diffuse thickening, the pattern of attenuation in light of clinical findings helps narrowing the differential diagnosis. CONCLUSION: Focal bowel wall thickening may be caused by tumours or inflammatory conditions. Bowel tumours may appear as either regular and symmetric or irregular or asymmetric thickening. When fat stranding is disproportionately more severe than the degree of wall thickening, inflammatory conditions are more likely. With the exception of lymphoma, segmental or diffuse wall thickening is usually caused by benign conditions, such as ischaemic, infectious and inflammatory diseases. KEY POINTS: • Thickening of the bowel wall may be focal (<5 cm) and segmental or diffuse (6-40 cm or >40 cm) in extension. • Focal, irregular and asymmetrical thickening of the bowel wall suggests a malignancy. • Perienteric fat stranding disproportionally more severe than the degree of wall thickening suggests an inflammatory condition. • Regular, symmetric and homogeneous wall thickening is more frequently due to benign conditions, but can also be caused by neoplasms such as well-differentiated adenocarcinoma and lymphoma. • Segmental or diffuse bowel wall thickening is usually caused by ischaemic, inflammatory or infectious conditions and the attenuation pattern is helpful in narrowing the differential diagnosis.
Project description:miR319-targeted TCP genes are believed to regulate cell division in leaves and floral organs. However, it remains unknown whether these genes are involved in cell wall development. Here, we report that TCP24 negatively regulates secondary wall thickening in floral organs and roots. The overexpression of the miR319a-resistant version of TCP24 in Arabidopsis disrupted the thickening of secondary cell walls in the anther endothecium, leading to male sterility because of arrested anther dehiscence and pollen release. Several genes linked to secondary cell wall biogenesis and thickening were down-regulated in these transgenic plants. By contrast, the inhibition of TCP24 using the ectopic expression of a TCP24-SRDX repressor fusion protein, or the silencing of TCP genes by miR319a overexpression, increased cell wall lignification and the enhanced secondary cell wall thickening. Our results suggest that TCP24 acts as an important regulator of secondary cell wall thickening and modulates anther endothecium development.
Project description:Viral infection, particularly respiratory syncytial virus (RSV), causes inflammation in the bronchiolar airways (bronchial wall thickening, also known as bronchiolitis). This bronchial wall thickening is a common pathophysiological feature in RSV infection, but it causes more fatalities in infants than in children and adults. However, the molecular mechanism of RSV-induced bronchial wall thickening remains unknown, particularly in healthy adults. Using highly differentiated pseudostratified airway epithelium generated from primary human bronchial epithelial cells, we revealed RSV-infects primarily ciliated cells. The infected ciliated cells expanded substantially without compromising epithelial membrane integrity and ciliary functions and contributed to the increased height of the airway epithelium. Furthermore, we identified multiple factors, e.g., cytoskeletal (ARP2/3-complex-driven actin polymerization), immunological (IP10/CXCL10), and viral (NS2), contributing to RSV-induced uneven epithelium height increase in vitro. Thus, RSV-infected expanded cells contribute to a noncanonical inflammatory phenotype, which contributes to bronchial wall thickening in the airway, and is termed cytoskeletal inflammation.
Project description:BackgroundDiesel exhaust (DE) is a major source of ultrafine particulate matters (PM) in ambient air and contaminates many occupational settings. Airway remodeling assessed using computerized tomography (CT) correlates well with spirometry in patients with obstructive lung diseases. Structural changes of small airways caused by chronic DE exposure is unknown. Wall and lumen areas of 6th and 9th generations of four candidate airways were quantified using end-inhalation CT scans in 78 diesel engine testers (DET) and 76 non-DETs. Carbon content in airway macrophage (CCAM) in sputum was quantified to assess the dose-response relationship.ResultsEnvironmental monitoring and CCAM showed a much higher PM exposure in DETs, which was associated with higher wall area and wall area percent for 6th generation of airways. However, no reduction in lumen area was identified. No study subjects met spirometry diagnosis of airway obstruction. This suggested that small airway wall thickening without lumen narrowing may be an early feature of airway remodeling in DETs. The effect of DE exposure status on wall area percent did not differ by lobes or smoking status. Although the trend test was of borderline significance between categorized CCAM and wall area percent, subjects in the highest CCAM category has a 14% increase in wall area percent for the 6th generation of airways compared to subjects in the lowest category. The impact of DE exposure on FEV1 can be partially explained by the wall area percent with mediation effect size equal to 20%, Pperm = 0.028).ConclusionsSmall airway wall thickening without lumen narrowing may be an early image feature detected by CT and underlie the pathology of lung injury in DETs. The pattern of changes in small airway dimensions, i.e., thicker airway wall without lumen narrowing caused by occupational DE exposure was different to that (i.e., thicker airway wall with lumen narrowing) seen in our previous study of workers exposed to nano-scale carbon black aerosol, suggesting constituents other than carbon cores may contribute to such differences. Our study provides some imaging indications of the understanding of the pulmonary toxicity of combustion derived airborne particulate matters in humans.