Jens Waldmann

Integrated genomic characterization of adrenocortical carcinoma

Adrenocortical carcinomas (ACCs) are aggressive cancers originating in the cortex of the adrenal gland. Despite overall poor prognosis, ACC outcome is heterogeneous. We performed exome sequencing and SNP array analysis of 45 ACCs and identified recurrent alterations in known driver genes (CTNNB1, TP53, CDKN2A, RB1 and MEN1) and in genes not previously reported in ACC (ZNRF3, DAXX, TERT and MED12), which we validated in an independent cohort of 77 ACCs. ZNRF3, encoding a cell surface E3 ubiquitin ligase, was the most frequently altered gene (21%) and is a potential new tumor suppressor gene related to the β-catenin pathway. Our integrated genomic analyses further identified two distinct molecular subgroups with opposite outcome. The C1A group of ACCs with poor outcome displayed numerous mutations and DNA methylation alterations, whereas the C1B group of ACCs with good prognosis displayed specific deregulation of two microRNA clusters. Thus, aggressive and indolent ACCs correspond to two distinct molecular entities driven by different oncogenic alterations.

Comprehensive Pan-Genomic Characterization of Adrenocortical Carcinoma

We describe a comprehensive genomic characterization of adrenocortical carcinoma (ACC). Using this dataset, we expand the catalogue of known ACC driver genes to include PRKAR1A, RPL22, TERF2, CCNE1, and NF1. Genome wide DNA copy-number analysis revealed frequent occurrence of massive DNA loss followed by whole-genome doubling (WGD), which was associated with aggressive clinical course, suggesting WGD is a hallmark of disease progression. Corroborating this hypothesis were increased TERT expression, decreased telomere length, and activation of cell-cycle programs. Integrated subtype analysis identified three ACC subtypes with distinct clinical outcome and molecular alterations which could be captured by a 68-CpG probe DNA-methylation signature, proposing a strategy for clinical stratification of patients based on molecular markers.

Surgical management of pancreatic endocrine tumors.

Pancreatic endocrine tumors (PETs) are uncommon but clinically challenging and fascinating tumors with an annual incidence of 1 per 100,000 people. PETs present as either functional pancreatic tumors or as nonfunctional pancreatic tumors. Functional tumors are commonly associated with a specific hormonal syndrome directly related to a hormone secreted by the tumor, such as Zollinger–Ellison syndrome or organic hyperinsulinism. Nonfunctional tumors do not secrete a hormone resulting in a pathologic syndrome of clinical symptoms. The natural history of PETs is highly variable. Small, benign neoplasms, such as 90% of all insulinomas, are readily curable by surgical resection; however, most other functional and all nonfunctional pancreatic tumors have a much less favorable prognosis. Patients with completely resected tumors generally have a good prognosis, and an aggressive surgical approach in patients with advanced disease may also prolong survival. Many features of the management of pancreatic endocrine tumors, such as timing and extent of resection, and the use of laparoscopic procedures, are currently under debate. This Review describes the current status of surgical treatment for pancreatic endocrine tumors, and discusses the new developments in this field.

The Angiotensin-I-converting Enzyme Inhibitor Enalapril and Aspirin delay progression of Pancreatic Intraepithelial Neoplasia and cancer formation in a genetically engineered mouse model of pancreatic cancer

Background and aims There are no chemopreventive strategies for pancreatic cancer or its precursor lesions, pancreatic intraepithelial neoplasia (PanINs). Recent evidence suggests that aspirin and inhibitors of angiotensin-I converting enzyme (ACE inhibitors) have potential chemopreventive properties. In this study, we used a genetically engineered mouse model of pancreatic cancer to evaluate the chemopreventive potential of these drugs. Methods Drug treatment was initiated at the age of 5 weeks. LsL-KrasG12D; Pdx1-Cre or LsL-KrasG12D; LsL-Trp53R172H; Pdx1-Cre transgenic mice were randomly assigned to receive either mock treatment, aspirin, enalapril, or a combination of both. After 3 and 5 months, animals were killed. The effect of aspirin and enalapril was evaluated by histopathological analyses, immunostaining, and real-time PCR. Results After 3 and 5 months of treatment, enalapril and aspirin were able to significantly delay progression of mPanINs in LsL-KrasG12D; Pdx1-Cre mice. Furthermore, development of invasive pancreatic cancer in LsL-KrasG12D; LsL-Trp53R172H; Pdx1-Cre transgenic mice was partially inhibited by enalapril and aspirin. Invasive pancreatic cancer was identified in 15 of 25 (60%) LsL-KrasG12D; LsL-Trp53R172H; Pdx1-Cre untreated control mice, but in only three of 17 (17.6%, p=0.01) mice treated with aspirin, in four of 17 (23.5%, p=0.03) in mice treated with enalapril alone, and in five of 16 (31.2%, p=0.11) mice treated with a combination of both drugs. Using real-time PCR we found a significant downregulation of the target genes VEGF and RelA demonstrating our ability to achieve effective pharmacological levels of aspirin and enalapril during pancreatic cancer formation in vivo. Conclusion Using a transgenic mouse model that imitates human pancreatic cancer, this study provides first evidence that aspirin and enalapril are effective chemopreventive agents by delaying the progression of PanINs and partially inhibiting the formation of murine pancreatic cancer. This study together supports the hypothesis that aspirin and ACE inhibitors might be a valid chemopreventive strategy.

Major Prognostic Role of Ki67 in Localized Adrenocortical Carcinoma After Complete Resection

BACKGROUND Recurrence of adrenocortical carcinoma (ACC) even after complete (R0) resection occurs frequently. OBJECTIVE The aim of this study was to identify markers with prognostic value for patients in this clinical setting. DESIGN, SETTING, AND PARTICIPANTS From the German ACC registry, 319 patients with the European Network for the Study of Adrenal Tumors stage I-III were identified. As an independent validation cohort, 250 patients from three European countries were included. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Clinical, histological, and immunohistochemical markers were correlated with recurrence-free (RFS) and overall survival (OS). RESULTS Although univariable analysis within the German cohort suggested several factors with potential prognostic power, upon multivariable adjustment only a few including age, tumor size, venous tumor thrombus (VTT), and the proliferation marker Ki67 retained significance. Among these, Ki67 provided the single best prognostic value for RFS (hazard ratio [HR] for recurrence, 1.042 per 1% increase; P < .0001) and OS (HR for death, 1.051; P < .0001) which was confirmed in the validation cohort. Accordingly, clinical outcome differed significantly between patients with Ki67 <10%, 10-19%, and ≥20% (for the German cohort: median RFS, 53.2 vs 31.6 vs 9.4 mo; median OS, 180.5 vs 113.5 vs 42.0 mo). Using the combined cohort prognostic scores including tumor size, VTT, and Ki67 were established. Although these scores discriminated slightly better between subgroups, there was no clinically meaningful advantage in comparison with Ki67 alone. CONCLUSION This largest study on prognostic markers in localized ACC identified Ki67 as the single most important factor predicting recurrence in patients following R0 resection. Thus, evaluation of Ki67 indices should be introduced as standard grading in all pathology reports of patients with ACC.

Novel somatic mutations in the catalytic subunit of the protein kinase A as a cause of adrenal Cushing's syndrome: a European multicentric study.

CONTEXT Somatic mutations in PRKACA gene, encoding the catalytic subunit of protein kinase A (PKA), have been recently found in a high proportion of sporadic adenomas associated with Cushings syndrome. The aim was to analyze the PRKACA mutation in a large cohort of patients with adrenocortical masses. METHODS Samples from nine European centers were included (Germany, n = 4; Italy, n = 4; France, n = 1). Samples were drawn from 149 patients with nonsecreting adenomas (n = 32 + 2 peritumoral), subclinical hypercortisolism (n = 36), Cushings syndrome (n = 64 + 2 peritumoral), androgen-producing tumors (n = 4), adrenocortical carcinomas (n = 5 + 2 peritumoral), and primary bilateral macronodular adrenal hyperplasias (n = 8). Blood samples were available from patients with nonsecreting adenomas (n = 15), subclinical hypercortisolism (n = 10), and Cushings syndrome (n = 35). Clinical and hormonal data were collected. DNA amplification by PCR of exons 6 and 7 of the PRKACA gene and direct sequencing were performed. RESULTS PRKACA heterozygous mutations were found in 22/64 samples of Cushings syndrome patients (34%). No mutations were found in peritumoral tissue and blood samples or in other tumors examined. The c.617A>C (p.Leu206Arg) occurred in 18/22 patients. Furthermore, two novel mutations were identified: c.600_601insGTG/p.Cys200_Gly201insVal in three patients and c.639C>G+c.638_640insATTATCCTGAGG/p.Ser213Arg+p.Leu212_Lys214insIle-Ile-Leu-Arg) in one. All the mutations involved a region implicated in interaction between PKA regulatory and catalytic subunits. Patients with somatic PRKACA mutations showed higher levels of cortisol after dexamethasone test and a smaller adenoma size, compared with nonmutated subjects. CONCLUSIONS These data confirm and extend previous observations that somatic PRKACA mutations are specific for adrenocortical adenomas causing Cushings syndrome.

Snail and Sonic Hedgehog activation in neuroendocrine tumors of the ileum

The transcription factor Snail represses E-cadherin and induces epithelial-mesenchymal transition, a process also exploited by invasive cancer cells. Aberrant Hedgehog (Hh) signaling was recently observed in a variety of epithelial cancers and it has been shown that the Hh target gene Gli1 induces expression of Snail. In this study, we examined whether Snail and Sonic Hedgehog (SHH) are expressed in neuroendocrine tumors (NETs) of the ileum. Using immunohistochemistry, we found expression of Snail in 22 out of 37 (59%) of evaluated NET samples, but not in adjacent normal tissues. Snail expression was mostly restricted to the invasive front of the tumors. Six of seven liver metastases analyzed were positive for Snail. Intratumoral expression of SHH was detected in 27 out of 37 (73%) tumors. As opposed to Snail, cells expressing SHH were found to be distributed more randomly throughout the tumors. Out of 30 primary NETs, 16 (53%) showed both Snail and SHH expression. Furthermore, we found downregulation of E-cadherin in Snail-expressing cells by immunofluorescence. Real-time RT-PCR revealed conservation of the Hh target genes Gli1, Gli2, and Ptch in the pancreatic carcinoid cell line BON-1, which were downregulated upon Hh inhibition with cyclopamine. Moreover, Hh inhibition attenuated in vitro cell growth in a dose-dependent manner. In conclusion, we describe for the first time that Snail and SHH are overexpressed in a large subset of NETs of the ileum. Aberrant activation of these pathways might be involved in invasion and metastatic spread in NETs.

Partial pancreaticoduodenectomy can provide cure for duodenal gastrinoma associated with multiple endocrine neoplasia type 1.

Objective: To evaluate the outcome of pancreaticoduodenectomy (PD) versus non-PD resections for the treatment of gastrinoma in multiple endocrine neoplasia type 1. Background: Gastrinoma in MEN1 is considered a rarely curable disease and its management is highly controversial both for timing and extent of surgery. Methods: Clinical characteristics, complications and outcomes of 27 prospectively collected MEN1 patients with biochemically proven gastrinoma, who underwent surgery, were analyzed with special regard to the gastrinoma type and the initial operative procedure. Results: Twenty-two (81%) patients with gastrinoma in MEN1 had duodenal gastrinomas and 5 patients (19%) had pancreatic gastrinomas. At the time of diagnosis, 21 (77%) gastrinomas were malignant (18 duodenal, 3 pancreatic), but distant metastases were only present in 4 (15%) patients. Patients with pancreatic gastrinomas underwent either distal pancreatic resections or gastrinoma enucleation with lymphadenectomy, 2 patients also had synchronous resections of liver metastases. One of these patients was biochemically cured after a median of 136 (77–312) months. Thirteen patients with duodenal gastrinomas underwent PD resections (group 1, partial PD [n = 11], total PD [n = 2]), whereas 9 patients had no-PD resections (group 2) as initial operative procedure. Perioperative morbidity and mortality, including postoperative diabetes, differed not significantly between groups (P > 0.5). All patients of group 1 and 5 of 9 (55%) patients of group 2 had a negative secretin test at hospital discharge. However, after a median follow-up of 136 (3–276) months, 12 (92%) patients of group 1 were still normogastrinemic compared to only 3 of 9 (33%) patients of group 2 (P = 0.023). Three (33%) patients of group 2 had to undergo up to 3 reoperations for recurrent or metastatic disease compared to none of group 1. Conclusions: Duodenal gastrinoma in MEN1 should be considered a surgically curable disease. PD seems to be the adequate approach to this disease, providing a high cure rate and acceptable morbidity compared to non-PD resections.

Expression of the zinc-finger transcription factor Snail in adrenocortical carcinoma is associated with decreased survival

In this study, we evaluate whether Snail is expressed in adrenocortical cancer (ACC) and if its expression is related to patient outcome. One of the best known functions of the zinc-finger transcription factor Snail is to induce epithelial-to-mesenchymal transition (EMT). Increasing evidence suggests that EMT plays a pivotal role in tumour progression and metastatic spread. Snail and E-cadherin expression were assessed by immunohistochemistry in 26 resected ACCs and real-time quantitative RT–PCR expression analysis was performed. Data were correlated with clinical outcome and in particular with overall patient survival. Seventeen of 26 (65%) ACC tumour samples expressed Snail when assessed by immunohistochemistry. Snail expression was neither detected in normal adrenocortical tissue, nor in benign adrenocortical adenomas. Expression levels were confirmed on the mRNA level by Real-Time–PCR. Survival rates were significantly decreased in Snail-positive tumours compared to Snail-negative tumours: 10 out of 16 vs one out of eight patients succumbed to disease after a median follow up of 14.5 and 28.5 months, respectively (P=0.03). Patients with Snail-expressing ACCs presented in advanced disease (11 out of 12 vs 6 out of 14, P=0.01) and tend to develop distant metastases more frequently than patients with negative staining (7 out of 11 vs two out of eight, P=0.19). In conclusion, we describe for the first time that Snail is expressed in a large subset of ACCs. Furthermore, Snail expression is associated with decreased survival, advanced disease and higher risk of developing distant metastases.

Unique expression pattern of the EMT markers Snail, Twist and E-cadherin in benign and malignant parathyroid neoplasia

BACKGROUND Epithelial and mesenchymal transitions (EMT) are essential for embryonic development and progression of non-invasive tumor cells into malignant, metastatic carcinomas. During embryogenesis, the parathyroid glands develop from pharyngeal pouches and migrate to their final destinations, densely enclosed by mesenchymal neural crest cells. In this study, we examined the expression of the EMT markers Snail, Twist and E-cadherin in normal parathyroid glands and benign and malignant parathyroid diseases. METHODS Using immunohistochemistry, we compared expression of E-cadherin, Snail and Twist in 25 patients with parathyroid adenoma, 25 patients with parathyroid hyperplasia, and nine patients with parathyroid cancer with normal parathyroid glands. RESULTS Normal parathyroid glands, parathyroid adenomas, and parathyroid hyperplasias showed a typical membranous E-cadherin staining pattern. Expression of Snail was found in 22/25 parathyroid adenomas and in all parathyroid hyperplasias. Twist was expressed in 22/25 of parathyroid adenomas and in 20/25 parathyroid hyperplasias. Snail and Twist positive cells were homogeneously distributed throughout the gland. However, in all nine parathyroid carcinomas, membranous E-cadherin staining was lost. In addition, the expression pattern of Snail and Twist was changed and mostly limited to the invasive front of cancer tissue samples. CONCLUSION Expression of Snail and Twist at the invasive front and consecutive loss of E-cadherin in parathyroid carcinomas suggests a key role of EMT in the tumorigenesis of this cancer. The unique expression pattern could help to distinguish between an adenoma and a non-metastatic carcinoma. Loss of E-cadherin and change of the expression pattern of Snail and Twist together should result in an en bloc resection or a close follow-up.