PDGFRβ expression in tumor stroma of pancreatic adenocarcinoma as a reliable prognostic marker

Pancreatic adenocarcinoma is a lethal disease that often develops a desmoplastic reaction in tumor stroma. In general, desmoplasia is thought to promote tumor growth. However, its molecular pathology and prognostic potential have not been fully investigated. Here, we investigate 26 cases of pancreatic ductal adenocarcinoma and examine the clinicopathological association between survival and expression levels of several molecular markers for stromal cells. These include alpha smooth muscle actin (SMA) and platelet-derived growth factor (PDGF) receptor β (PDGFRβ). Both are markers of activated fibroblasts or pancreatic stellate cells (PSCs) that play an important role in desmoplasia. The staining patterns of both molecular markers were not uniform so we categorized them into 3 grades (high, middle, and low) according to intensity. Interestingly, Kaplan-Meier analysis revealed that higher expression of PDGFRβ matched shorter prognosis (p = 0.0287, log-rank test) as well as lymphatic invasion and lymph node metastasis, whereas SMA did not (p = 0.6122). Our results suggest the prognostic potential of cancer stroma via PDGF-B signaling. Regulation of PDGF-B-associated signaling crosstalk between cancer cells and stroma cells, therefore, may indicate a possible therapeutic target for desmoplastic malignant tumors such as pancreatic adenocarcinoma

Chylous ascites after nephrectomy without lymphadenectomy for malignant rhabdoid tumor of the kidney: A rare occurrence and literature review

Chylous ascites (CA) is an extremely rare complication of abdominal surgery in children. This report describes a 4-month-old girl with malignant rhabdoid tumor of the kidney (MRTK), who developed CA after left nephrectomy without lymphadenectomy, and who was successfully treated conservatively with enteral therapy. The literature on CA after nephrectomy without lymphadenectomy for MRTK is reviewed herein, and the clinical problems of postoperative CA are discussed

Prognostic significance of mesothelin expression in colorectal cancer disclosed by area-specific four-point tissue microarrays

I.P.N. is the recipient of a Medical Research Scotland PhD Studentship awarded to P.D.C.Mesothelin (MSLN) is a cell surface glycoprotein present in many cancer types. Its expression is generally associated with an unfavorable prognosis. This study examined the prognostic significance of MSLN expression in different areas of individual colorectal cancers (CRCs) using tissue microarrays (TMAs) by enrolling 314 patients with stage II (T3-T4, N0, M0) CRCs. Using formalin-fixed paraffin-embedded tissue blocks from patients, TMA blocks were constructed. Tissue core specimens were obtained from submucosal invasive front (Fr-sm), subserosal invasive front (Fr-ss), central area (Ce), and rolled edge (Ro) of each tumor. Using these four-point TMA sets, MSLN expression was immunohistochemically surveyed. The area-specific prognostic significance of MSLN expression was evaluated. A deep learning convolutional neural network algorithm was used for imaging analysis and evaluating our judgment's objectivity. MSLN staining ratio was positively correlated between the manual and machine-learning analyses (r = 0.71). The correlation coefficient between Ro and Ce, Ro and Fr-sm, and Ro and Fr-ss was r = 0.63, r = 0.54, and r = 0.61, respectively. Disease-specific survival curves for the MSLN-positive and MSLN-negative groups in Fr-sm, Fr-ss, and Ro were significantly different (five-year survival rates 88.1% and 95.5% (P = 0.024), 85.0 and 96.2% (P = 0.0087), 87.8 and 95.5% (P = 0.051), and 77.9 and 95.8% (P = 0.046) for Fr-sm, Fr-ss, Ce, and Ro, respectively). The analysis performed using area-specific four-point TMAs clearly demonstrated that MSLN expression in stage II CRC was relatively homogeneous within tumors. Additionally, high MSLN expression showed or tended to show unfavorable prognostic significance regardless of the tumor area.PostprintPeer reviewe

Intracellular localization of mesothelin predicts patient prognosis of extrahepatic bile duct cancer.

Mesothelin is expressed in various types of malignant tumors, and we recently reported that the expression of mesothelin was related to unfavorable patient outcome in pancreatic ductal adenocarcinoma and gastric adenocarcinoma. In this study, we examined the clinicopathological significance of mesothelin expression in extrahepatic bile duct cancer (EHBDCA), especially in terms of its association with the staining pattern. Tissue samples from 61 EHBDCA (16 hilar cholangiocarcinoma, 17 upper bile duct adenocarci-noma, 20 middle bile duct adenocarcinoma and 8 distal bile duct adenocarcinoma) were immunohistochemically examined. The expression levels of mesothelin in tumor cells was classified into the localization of mesothelin in luminal membrane and/or cytoplasm, in addition to high and low according to the staining intensity and proportion as a conventional analysis. 'High-level expression' of mesothelin (47.5%) was statistically correlated with liver metastasis (P=0.013) and poorer patient outcome (P=0.022), while 'luminal membrane positive' of mesothelin (52.5%) was more significantly correlated with liver metastasis (P=0.006), peritoneal metastasis (P=0.024) and unfavorable patient outcome (P=0.017). Moreover, we found that 'cytoplasmic expression' isolated from 'luminal membrane negative' of mesothelin represented the best patient prognosis throughout this study. We describe the expression pattern level of mesothelin, i.e., in luminal membrane or cytoplasm both high and low level, evidently indicate the patient prognosis of EHBDCA, suggesting the pivotal role of mesothelin in cancer promotion depending on its intracellular localization

Membranous and cytoplasmic expression of epidermal growth factor receptor in metastatic pancreatic ductal adenocarcinoma

PublisherRecent studies indicate the clinical significance of the cellular localization of epidermal growth factor receptor (EGFR) in a variety of cancer types. Internalization of activated EGFR is reported to be closely associated with patient prognosis. This study investigated the clinical significance of the immunohistochemical localization of EGFR in patients with metastatic pancreatic cancers compared to those with surgically resected pancreatic cancers. Using 44 surgically resected primary pancreatic cancers and 40 primary or meta-static tumors from 20 autopsied patients with far advanced pancreatic cancers, the incidence of membranous and cytoplasmic EGFR overexpression was compared between primary tumors and far advanced tumors by immunohistochemistry using the Dako EGFR pharmDx™ kit, a global standard kit for EGFR assay. In the 44 surgically resected cancers, 13 (30%) exhibited membranous overexpression of EGFR, comprising 1 case (2%) with score 3+ and 12 cases (27%) with score 2+ and 10 (23%) exhibited cytoplasmic overexpression of EGFR. In the 40 tumors at a far advanced stage, the percentage of samples exhibiting positivity for membranous and cytoplasmic EGFR overexpression was 48% (19 of 40) comprising 7 (18%) with score 2+ and 12 (30%) with score 3+ and 33% (13 of 40), respectively. The far advanced tumors tended to show membranous and cytoplasmic EGFR overexpression more frequently than the surgically resected tumors, although the difference was not significant. These findings suggest that membranous and cytoplasmic overexpression of EGFR may be indicative of the potential aggressiveness of pancreatic cancers

Chylous ascites after nephrectomy without lymphadenectomy for malignant rhabdoid tumor of the kidney: A rare occurrence and literature review

Chylous ascites (CA) is an extremely rare complication of abdominal surgery in children. This report describes a 4-month-old girl with malignant rhabdoid tumor of the kidney (MRTK), who developed CA after left nephrectomy without lymphadenectomy, and who was successfully treated conservatively with enteral therapy. The literature on CA after nephrectomy without lymphadenectomy for MRTK is reviewed herein, and the clinical problems of postoperative CA are discussed

Predictive factors for microscopic portal venous invasion and the place of anatomic liver resection

Background: The aims of this study were to investigate predictive factors for microscopic portal venous invasion (mPVI) in hepatocellular carcinoma (HCC) and whether anatomical liver resection (ALR) was useful in such cases. Methods: We analyzed 852 patients with HCC without macroscopic portal venous invasion who were treated at our hospital between January 1990 and May 2014. These patients were stratified into a microscopic portal venous invasion group (mPVI group; n = 153) and non-microscopic portal venous invasion group (NmPVI group; n = 699). Results: PIVKA-II ≥100 mAU/ml, a tumor size ≥5 cm, a confluent lesion, and poor differentiation were found to be independent risk factors for mPVI. Among the mPVI group who had single HCC under 5 cm, serum albumin level <4.0 g/dl, PIVKA-II ≥100 mAU/ml, a positive surgical margin, and non-ALR (NALR) were independent unfavorable prognostic factors for overall survival (OS). PIVKA-II ≥100 mAU/ml, a positive surgical margin and NALR were independent unfavorable prognostic factors for relapse-free survival (RFS). ALR was significantly favorable factor for both OS and RFS of the mPVI group who had single HCC under 5 cm. Conclusions: Even if no portal venous invasion is detectable in HCC patients preoperatively, a PIVKA-II ≥100 mAU/ml, tumor size ≥5 cm, and a confluent lesion indicate a high risk of mPVI. ALR should be considered for the patients with these characteristics because it is a favorable prognostic factor in these cases with mPVI

Mesothelin blockage by Amatuximab suppresses cell invasiveness, enhances gemcitabine sensitivity and regulates cancer cell stemness in mesothelin-positive pancreatic cancer cells

Background Mesothelin is a 40-kDa glycoprotein that is highly overexpressed in various types of cancers, however molecular mechanism of mesothelin has not been well-known. Amatuximab is a chimeric monoclonal IgG1/k antibody targeting mesothelin. We recently demonstrated that the combine therapy of Amatuximab and gemcitabine was effective for peritonitis of pancreatic cancer in mouse model. Methods We discover the role and potential mechanism of mesothelin blockage by Amatuximab in human pancreatic cells both expressing high or low level of mesothelin in vitro experiment and peritonitis mouse model of pancreatic cancer. Results Mesothelin blockage by Amatuximab lead to suppression of invasiveness and migration capacity in AsPC-1 and Capan-2 (high mesothelin expression) and reduce levels of pMET expression. The combination of Amatuximab and gemcitabine suppressed proliferation of AsPC-1 and Capan-2 more strongly than gemcitabine alone. These phenomena were not observed in Panc-1 and MIA Paca-2 (Mesothelin low expression). We previously demonstrated that Amatuximab reduced the peritoneal mass in mouse AsPC-1 peritonitis model and induced sherbet-like cancer cell aggregates, which were vanished by gemcitabine. In this study, we showed that the cancer stem cell related molecule such as ALDH1, CD44, c-MET, as well as proliferation related molecules, were suppressed in sherbet-like aggregates, but once sherbet-like aggregates attached to peritoneum, they expressed these molecules strongly without the morphological changes. Conclusions Our work suggested that Amatuximab inhibits the adhesion of cancer cells to peritoneum and suppresses the stemness and viability of those, that lead to enhance the sensitivity for gemcitabine