Whole-exome sequencing of calcitonin-producing pancreatic neuroendocrine neoplasms indicates a unique molecular signature.

Introduction: Calcitonin-producing pancreatic neuroendocrine neoplasms (CT-pNENs) are an extremely rare clinical entity, with approximately 60 cases reported worldwide. While CT-pNENs can mimic the clinical and diagnostic features of medullary thyroid carcinoma, their molecular profile is poorly understood. Methods: Whole-exome sequencing (WES) was performed on tumor and corresponding serum samples of five patients with increased calcitonin serum levels and histologically validated calcitonin-positive CT-pNENs. cBioPortal analysis and DAVID gene enrichment analysis were performed to identify dysregulated candidate genes compared to control databases. Immunohistochemistry was used to detect the protein expression of MUC4 and MUC16 in CT-pNEN specimens. Results: Mutated genes known in the literature in pNENs like MEN1 (35% of cases), ATRX (18-20% of cases) and PIK3CA (1.4% of cases) were identified in cases of CT-pNENs. New somatic SNVs in ATP4A, HES4, and CAV3 have not been described in CT- pNENs, yet. Pathogenic germline mutations in FGFR4 and DPYD were found in three of five cases. Mutations of CALCA (calcitonin) and the corresponding receptor CALCAR were found in all five tumor samples, but none of them resulted in protein sequelae or clinical relevance. All five tumor cases showed single nucleotide variations (SNVs) in MUC4, and four cases showed SNVs in MUC16, both of which were membrane-bound mucins. Immunohistochemistry showed protein expression of MUC4 in two cases and MUC16 in one case, and the liver metastasis of a third case was double positive for MUC4 and MUC16. The homologous recombination deficiency (HRD) score of all tumors was low. Discussion: CT-pNENs have a unique molecular signature compared to other pNEN subtypes, specifically involving the FGFR4, DPYD, MUC4, MUC16 and the KRT family genes. However, a major limitation of our study was the relative small number of only five cases. Therefore, our WES data should be interpreted with caution and the mutation landscape in CT-pNENs needs to be verified by a larger number of patients. Further research is needed to explain differences in pathogenesis compared with other pNENs. In particular, multi-omics data such as RNASeq, methylation and whole genome sequencing could be informative.

Inbreeding and selection on sex ratio in the bark beetle Xylosandrus germanus.

BACKGROUND: Local Mate Competition (LMC) theory predicts a female should produce a more female-biased sex ratio if her sons compete with each other for mates. Because it provides quantitative predictions that can be experimentally tested, LMC is a textbook example of the predictive power of evolutionary theory. A limitation of many earlier studies in the field is that the population structure and mating system of the studied species are often estimated only indirectly. Here we use microsatellites to characterize the levels of inbreeding of the bark beetle Xylosandrus germanus, a species where the level of LMC is expected to be high. RESULTS: For three populations studied, genetic variation for our genetic markers was very low, indicative of an extremely high level of inbreeding (F(IS) = 0.88). There was also strong linkage disequilibrium between microsatellite loci and a very strong genetic differentiation between populations. The data suggest that matings among non-siblings are very rare (3%), although sex ratios from X. germanus in both the field and the laboratory have suggested more matings between non-sibs, and so less intense LMC. CONCLUSIONS: Our results confirm that caution is needed when inferring mating systems from sex ratio data, especially when a lack of biological detail means the use of overly simple forms of the model of interest.

Adult Proinsulinomatosis Associated With a MAFA Germline Mutation as a Rare Cause of Recurrent Hypoglycemia.

ABSTRACT: Sporadic adult insulinomatosis is an extremely rare clinical condition. Adult proinsulinomatosis has not yet been described. We report the case of a 48-year-old female patient with recurrent hypoglycemia caused by benign proinsulin-secreting pancreatic neuroendocrine neoplasias (pNENs) with no history of multiple endocrine neoplasia type 1. Initial workup revealed elevated serum proinsulin levels and a positive fasting test. Magnetic resonance imaging and endosonography visualized 2 pNENs in the pancreatic body and tail that were treated by robotic-assisted enucleation. After initial biochemical cure, the patient's hypoglycemia recurred 3 months after surgery. Imaging showed a new lesion in the pancreatic body, so that now a spleen-preserving subtotal distal pancreatectomy was performed. The pathological examination revealed 17 neuroendocrine microadenomas and 1 well-differentiated pNEN (Ki-67% 1%-2%) of 22-mm size as well as more than 200 (pro)insulin-producing ß-cell precursor lesions, confirming the diagnosis of adult proinsulinomatosis. Mutation analysis of the germline DNA identified the in-frame deletion mutation (p.His207del) in the MAFA gene on chromosome 8. The patient was biochemically cured 16 months after the last surgical resection. Similarly to adult insulinomatosis, the presence of proinsulin-secreting tumors causes recurrent hypoglycemia and might be associated with germline mutations in the MAFA gene.

Two giant retroperitoneal schwannomas mimicking adrenal malignancy - a case report.

Schwannomas are benign tumors in 95% of cases and very rarely occur in the retroperitoneum. We report the cases of a 35-year-old man with abdominal discomfort and a 50-year-old asymptomatic woman with large retroperitoneal masses. Both underwent multivisceral surgery to exclude an adrenal carcinoma, and the pathologic diagnosis showed schwannomas in both cases. Despite morphological imaging, it was not possible to get a clear diagnosis preoperatively.

Berberis orthobotrys - A promising herbal anti-tumorigenic candidate for the treatment of pediatric alveolar rhabdomyosarcoma.

ETHNOPHARMACOLOGICAL RELEVANCE: Berberis orthobotrys (BORM) is a medical plant with a long history in traditional usage for the treatment of wounds, cancer, gastrointestinal malady and several other diseases. Our previous studies identified the endemic Pakistani plant Berberis orthobotrys Bien. ex Aitch. as promising source for the treatment of breast cancer and osteosarcoma. AIM OF THE STUDY: The present study was aimed to evaluate the anti-cancer properties of 26 plant derived extracts and compounds including the methanolic root extract of Berberis orthobotrys (BORM) on pediatric alveolar rhabdomyosarcoma (RMA), which is known to develop drug resistance, metastatic invasion and potential tumor progression. MATERIALS AND METHODS: The main anti-tumor activity of BORM was verified by focusing on morphological, cell structural and metabolic alterations via metabolic profiling, cell viability measurements, flow cytometry, western blotting and diverse microscopy-based methods using the human RMA cell line Rh30. RESULTS: Exposure of 25 µg/ml BORM exerts an influence on the cell stability, the degradation of oncosomes as well as the shutdown of the metabolic activity of RMA cells, primarily by downregulation of the energy metabolism. Therefore glycyl-aspartic acid and N-acetyl serine decreased moderately, and uracil increased intracellularly. On healthy, non-transformed muscle cells BORM revealed very low metabolic alterations and nearly no cytotoxic impact. Furthermore, BORM is also capable to reduce Rh30 cell migration (~50%) and proliferation (induced G2/M cycle arrest) as well as to initiate apoptosis confirmed by reduced Bcl-2, Bax and PCNA expression and induced PARP-1 cleavage. CONCLUSIONS: The study provides the first evidence, that BORM treatment is effective against RMA cells with low side effects on healthy cells.

Outbreeding depression, but no inbreeding depression in haplodiploid Ambrosia beetles with regular sibling mating.

In sexual reproduction the genetic similarity or dissimilarity between mates strongly affects offspring fitness. When mating partners are too closely related, increased homozygosity generally causes inbreeding depression, whereas crossing between too distantly related individuals may disrupt local adaptations or coadaptations within the genome and result in outbreeding depression. The optimal degree of inbreeding or outbreeding depends on population structure. A long history of inbreeding is expected to reduce inbreeding depression due to purging of deleterious alleles, and to promote outbreeding depression because of increased genetic variation between lineages. Ambrosia beetles (Xyleborini) are bark beetles with haplodiploid sex determination, strong local mate competition due to regular sibling mating within the natal chamber, and heavily biased sex ratios. We experimentally mated females of Xylosandrus germanus to brothers and unrelated males and measured offspring fitness. Inbred matings did not produce offspring with reduced fitness in any of the examined life-history traits. In contrast, outcrossed offspring suffered from reduced hatching rates. Reduction in inbreeding depression is usually attributed to purging of deleterious alleles, and the absence of inbreeding depression in X. germanus may represent the highest degree of purging of all examined species so far. Outbreeding depression within the same population has previously only been reported from plants. The causes and consequences of our findings are discussed with respect to mating strategies, sex ratios, and speciation in this unusual system.