Insulin Receptor in Pancreatic Cancer-Crown Witness in Cross Examination

Background The proximity of pancreatic cancer (PDAC) to the physiological source of the growth promoting hormone insulin might be exploited by this highly malignant cancer entity. We investigated if (I) PDACs express the insulin receptor (IR) in cancer cells and cancer vasculature, (II) if IR correlates with clinicopathological patient characteristics, including survival, and hence is involved in PDAC biology, (III) if IR is already expressed in precursor lesions, if (IV) the IGF1 receptor (IGF1R) is associated with clinicopathological patient characteristics and survival and (V) is linked to IR expression. Methods 160 PDAC samples were examined for IR and IGF1R expression by immunohistochemistry. A modified HistoScore was correlated with clinicopathological characteristics and survival. Results IR overexpression was already observed in pancreatic intraepithelial neoplasia. Furthermore, it was more frequently observed in advanced disease and associated with distant metastasis, UICC stage, lymphatic invasion and an increased lymph node ratio, but without impacting survival in the end. IGF1R expression was not associated with clinicopathological parameters or survival, in contrast to former paradigms. Conclusions We hypothesize that the close proximity to the pancreatic islets might be advantageous for cancer growth at first, but it experiences self-limitation due to surgical removal or local destruction following accelerated cancer growth

Mucinous Cystic Neoplasm of Pancreas in a Pregnant Woman Presenting with Severe Anemia and Gastric Bleeding: Case Report and Review of the Literature

Mucinous cystic neoplasms of the pancreas are uncommon and especially their occurrence during pregnancy is an extremely rare event which necessitates an individualized and interdisciplinary management. A 33-year old woman was referred to our department during her third trimester of pregnancy (34th week of gestation) with severe anemia and tarry stools. Based on gastroscopic findings, our interdisciplinary team suspected a gastrointestinal stromal tumor and therefore indicated a prompt delivery via cesarean section completed with an oncological resection of the neoplasm. Histological examination subsequently showed a mucinous cystic neoplasm of the pancreas with no evidence of malignancy. To review the prevalence of mucinous cystic neoplasms and to discuss diagnosis and treatment during pregnancy. Moreover, we critically value the indication of preterm delivery and the oncological procedure in the perspective of outcome for mother and infant. A bleeding gastrointestinal tumor during pregnancy represents a life-threatening risk for mother and infant and requires an immediate interdisciplinary treatment. The urgency and radicality of the therapy should be adapted according to individual findings. As our patient's tumor was suspected of having a malignant progression, an extensive surgical intervention was necessary

Effect of Total Macroscopical Sampling of the Pediatric Appendectomy Specimen on Histopathological Diagnosis: EVALUATION OF PEDIATRIC APPENDECTOMY SPECIMEN

Introduction: Acute appendicitis is considered the most common abdominal surgery in children. Pathological examination of the appendectomy specimen mainly is performed to document the presence or absence of inflammation and confirm the clinical diagnosis. If the diagnosis made by the pathologist is as ‘no appendicitis’, then clinical work up for other causes should be performed. Routine macroscopic evaluation of the appendectomy specimen consists of obtaining one section each from the base, body and the tip of the appendix and additional sections obtained from exuding or perforated areas. The aim of this study is to evaluate if the final pathological diagnosis would change when the appendectomy specimen is sampled totally. Materials and Methods: In the present study, we performed conventional macroscopical sampling from the tip, body and base of the appendix and embedded these tissues in the first two cassettes, then the rest of appendix was completely sampled in additional two to five casettes. The histopathological diagnosis of conventionally sampled tissues and the histopathological diagnosis of total macroscopical sampling were analyzed and compared. Results: A total of 87 appendectomies were evaluated, of which 58.6 % were male, and the mean age was 11.7 (1 years-18 years). The initial histopathological diagnosis was changed in 14 (16%) cases. In 8 (9.2%) cases, the initial diagnosis of reactive lymphoid hyperplasia changed to acute focal appendicitis (early appendicitis). In 4 (4.6%) cases the initial diagnosis of acute suppurative appendicitis changed to acute suppurative and perforated appendicitis, and in 2 (2.2%) cases acute perforated appendicitis changed to acute perforated and gangrenous appendicitis. Conclusion: Total macroscopical sampling of the appendectomy specimen in cases of negative appendicitis would improve the diagnosis and can document early appendicitis in pediatric cases

Programmed Death-Ligand 1 (PD-L1) Expression Is Induced by Insulin in Pancreatic Ductal Adenocarcinoma Cells Pointing to Its Role in Immune Checkpoint Control

Type-2 diabetes (T2DM) is a risk factor for the development of pancreatic ductal adenocarcinoma (PDAC) and is characterized by insulin resistance and hyperinsulinemia. Besides the well-known growth-promoting activity of insulin or the other members of the Insulin/Insulin-like Growth factor (IGF) axis, we here describe an inducing effect of insulin on PD-L1 expression in PDAC cells. Treatment of the PDAC cell lines BxPc3, A818-6, and T3M4 with insulin increased PD-L1 expression in a time- and dose dependent fashion, as shown by Western blot and qPCR analysis. siRNA mediated knock-down showed that the effects of insulin on PD-L1 depend on the insulin and IGF receptors (InsR and IGFR, respectively). In addition, a crosstalk of insulin-induced ERK activation and Epidermal Growth Factor (EGF) triggered PD-L1 expression. This involves different mechanisms in the three cell lines including upregulation of InsR-A expression in A818-6 and modulation of the adaptor protein Gab1 in BxPc3 cells. As a consequence of the insulin-induced PD-L1 expression, PDAC cells suppress the proliferation of activated human CD8+ T-cells in coculture experiments. The suppression of CD8+ cell proliferation by insulin-pretreated PDAC cells was reversed by PD-1 blockade with Pembrolizumab or by PD-L1 siRNA. Furthermore, the clinical relevance of these observations was supported by detecting a coexpression of cytoplasmic InsR (characteristic for its activation) and PD-L1 in tumor tissues from PDAC patients. Our findings provide a novel insight into the protumorigenic role of insulin in PDAC. Recognizing the impact of insulin on PD-L1 expression as part of the immune privilege, strategies to interfere with this mechanism could pave the way towards a more efficient immunotherapy of PDAC

Genomic Analysis Revealed New Oncogenic Signatures in TP53-Mutant Hepatocellular Carcinoma

The TP53 gene is the most commonly mutated gene in human cancers and mutations in TP53 have been shown to have either gain-of-function or loss-of-function effects. Using the data generated by The Cancer Genome Atlas, we sought to define the spectrum of TP53 mutations in hepatocellular carcinomas (HCCs) and their association with clinicopathologic features, and to determine the oncogenic and mutational signatures in TP53-mutant HCCs. Compared to other cancer types, HCCs harbored distinctive mutation hotspots at V157 and R249, whereas common mutation hotspots in other cancer types, R175 and R273, were extremely rare in HCCs. In terms of clinicopathologic features, in addition to the associations with chronic viral infection and high Edmondson grade, we found that TP53 somatic mutations were less frequent in HCCs with cholestasis or tumor infiltrating lymphocytes, but were more frequent in HCCs displaying necrotic areas. An analysis of the oncogenic signatures based on the genetic alterations found in genes recurrently altered in HCCs identified four distinct TP53-mutant subsets, three of which were defined by CTNNB1 mutations, 1q amplifications or 8q24 amplifications, respectively, that co-occurred with TP53 mutations. We also found that mutational signature 12, a liver cancer-specific signature characterized by T>C substitutions, was prevalent in HCCs with wild-type TP53 or with missense TP53 mutations, but not in HCCs with deleterious TP53 mutations. Finally, whereas patients with HCCs harboring deleterious TP53 mutations had worse overall and disease-free survival than patients with TP53-wild-type HCCs, patients with HCCs harboring missense TP53 mutations did not have worse prognosis. In conclusion, our results highlight the importance to consider the genetic heterogeneity among TP53-mutant HCCs in studies of biomarkers and molecular characterization of HCCs

The contribution of additional sampling in cholecystectomy materials: A multicenter prospective study

Objective: Cholecystectomy materials arc frequently encountered in routine practice. The aim of this study was to determine the true frequency of gallbladder lesions, the diagnostic consistency, and standardization of reports after macroscopic sampling and microscopic evaluation based on previously defined criteria.Material and Method: 14 institutions participated in the study within the Hepato-Pancreato-Biliary Pathology Study Group. Routinely examined cholecystectomies within the last year were included in the study in these institutions. Additional sampling was performed according to the indications and criteria. The number of blocks and samples taken in the first macroscopic examination and the number of blocks and samples taken in the additional sampling were determined and the rate of diagnostic contribution of the additional examination was determined.Results: A total of 5,244 cholecystectomy materials from 14 institutions were included in the study. Additional sampling was found to be necessary in 576 cases (10.98%) from all institutions. In the first macroscopic sampling, the mean of the numbers of samples was approximately 4 and the number of blocks was 2. The mean of the numbers of additional samples and blocks was approximately 8 and 4, respectively. The diagnosis was changed in 144 of the 576 new sampled cases while the remaining 432 stayed unaltered.Conclusion: In this study, it was observed that new sampling after the first microscopic examination of cholecystectomy materials contributed to the diagnosis. It was also shown that the necessity of having standard criteria for macroscopic and microscopic examination plays an important role in making the correct diagnosis

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<p>The TP53 gene is the most commonly mutated gene in human cancers and mutations in TP53 have been shown to have either gain-of-function or loss-of-function effects. Using the data generated by The Cancer Genome Atlas, we sought to define the spectrum of TP53 mutations in hepatocellular carcinomas (HCCs) and their association with clinicopathologic features, and to determine the oncogenic and mutational signatures in TP53-mutant HCCs. Compared to other cancer types, HCCs harbored distinctive mutation hotspots at V157 and R249, whereas common mutation hotspots in other cancer types, R175 and R273, were extremely rare in HCCs. In terms of clinicopathologic features, in addition to the associations with chronic viral infection and high Edmondson grade, we found that TP53 somatic mutations were less frequent in HCCs with cholestasis or tumor infiltrating lymphocytes, but were more frequent in HCCs displaying necrotic areas. An analysis of the oncogenic signatures based on the genetic alterations found in genes recurrently altered in HCCs identified four distinct TP53-mutant subsets, three of which were defined by CTNNB1 mutations, 1q amplifications or 8q24 amplifications, respectively, that co-occurred with TP53 mutations. We also found that mutational signature 12, a liver cancer-specific signature characterized by T>C substitutions, was prevalent in HCCs with wild-type TP53 or with missense TP53 mutations, but not in HCCs with deleterious TP53 mutations. Finally, whereas patients with HCCs harboring deleterious TP53 mutations had worse overall and disease-free survival than patients with TP53-wild-type HCCs, patients with HCCs harboring missense TP53 mutations did not have worse prognosis. In conclusion, our results highlight the importance to consider the genetic heterogeneity among TP53-mutant HCCs in studies of biomarkers and molecular characterization of HCCs.</p