YAP1-MAML2-Rearranged Poroid Squamous Cell Carcinoma (Squamoid Porocarcinoma) Presenting as a Primary Parotid Gland Tumor

Porocarcinoma (synonym: malignant eccrine poroma) is a rare aggressive carcinoma type with terminal sweat gland duct differentiation. The squamous variant of porocarcinoma is even less frequent and might be indistinguishable from conventional squamous cell carcinoma (SCC). We herein describe the first case of a carcinoma presenting as a primary parotid gland malignancy in a 24-year-old male without any other primary tumor. Total parotidectomy and neck dissection were performed followed by adjuvant chemoradiation. The patient remained alive and well 10 months after diagnosis. Histology showed keratinizing SCC infiltrating extensively the parotid gland with subtle poroid cell features. Oncogenic HPV infection was excluded by DNA-based testing. NGS analysis using the TruSight RNA fusion panel (Illumina) revealed a novel YAP1-MAML2 gene fusion. This gene fusion was reported recently in a subset of cutaneous porocarcinoma and poroma. This case of poroid SCC (or squamoid porocarcinoma) adds to the differential diagnosis of SCC presenting as parotid gland tumor and highlights the value of molecular testing in cases with unusual presentation.Electronic supplementary materialThe online version of this article (10.1007/s12105-020-01181-9) contains supplementary material, which is available to authorized users.     

Long-term intrathecal S(+)-ketamine in a patient with cancer-related neuropathic pain

Neuropathic pain sometimes needs invasive pain therapy. We presentthe case of a patient with cancer-related neuropathic pain untreatablewith conventional pain therapy after tumour-embolization. Thepatient was treated successfully with intrathecal (i.t.) administrationof S(+)-ketamine, in addition to morphine. Plasma concentrationsof S(+)-ketamine were measured regularly throughout the treatment.Continuous i.t. administration of S(+)-ketamine over a periodof 3 months demonstrated low plasma levels and no unwanted side-effects.     

Chiral resolution, pharmacological characterization, and receptor docking of the noncompetitive mGlu1 receptor antagonist (+/-)-2-hydroxyimino- 1a, 2-dihydro-1H-7-oxacyclopropa[b]naphthalene-7a-carboxylic acid ethyl ester

Racemic CPCCOEt ((1aRS,7aRS)-2-hydroxyimino-1a, 2-dihydro-1H-7-oxacyclopropa[b]naphthalene-7a-carboxylic acid ethyl ester, (+/-)-1) derivatives have been shown to be subtype-selective metabotropic glutamate (mGlu) 1 receptor antagonists (Annoura et al. Bioorg. Med. Chem. Lett. 1996, 6, 763-766). The optical isomers of (+/-)-1 have been separated by chromatography on a chiral stationary phase. The absolute configuration at the C-1a and C-7a positions was determined using X-ray crystallography of an amide derivative with the methyl ester of L-phenylalanine (L-PheOMe) ((+)-6). In a phosphoinositol (PI) turnover assay at the cloned human mGlu1b receptor, (-)-1 and the new amide derivatives (-)-5 and (-)-6, all of which have (1aS,7aS)-stereochemistry on the chromane ring system, showed IC(50) values of 1.5, 0.43, and 0.93 microM, respectively. In contrast, (+)-1 and the new amide derivatives (+)-5 and (+)-6were found to be inactive up to a concentration of 30 microM indicating a selectivity for the (-)-enantiomers of at least 70-fold. In a previous study (Litschig et al. Mol. Pharmacol. 1999, 55, 453-461) we demonstrated using site-directed mutagenesis that the interaction site of (+/-)-1 is located in the transmembrane (TM) domain of hmGlu1b. To suggest a plausible binding mode of (-)-1, we have built a molecular mechanics model of the putative seven TM domain of hmGlu1 based on the alpha-carbon template of the TM helices of rhodopsin. A receptor docking hypothesis suggests that the OH of T815 (TMVII) comes in close contact with the oxime OH of (-)-1 and (-)-5, whereas no such close interactions could be demonstrated by docking of (+)-1.     

Expression and localization of the uptake transporters OATP2B1, OATP3A1 and OATP5A1 in non-malignant and malignant breast tissue

Organic anion transporting polypeptides (OATPs, gene family SLCO/SLC21) mediate the uptake of multiple endogenous substances such as estrogens and estrogen metabolites and of several widely prescribed drugs (e.g. statins, antibiotics and anticancer agents) into cells. Since several anticancer agents have been identified as substrates for OATPs, these transporters may also have an impact on cancer treatment. Expression of OATPs has been identified in colon, pancreatic and gastric carcinomas but to date little is known about the expression and localization of OATP family members in non-malignant breast tissue and breast cancer. We therefore analyzed the mRNA expression of all human OATP family members and further evaluated the mRNA amount of the highly-expressed OATPs OATP2B1, OATP3A1 and OATP5A1 in 10 paired samples of normal breast tissue and breast cancer. Furthermore, the tissue-specific localization of these OATPs was investigated. The results demonstrated that the mRNA expression of OATPs in normal and malignant breast tissue shows a high interindividual variability and that no significant differences in the mRNA amount between normal and malignant tissue could be detected. Furthermore, we localized OATP3A1 and OATP5A1 to the plasma membrane of epithelial cells of the lactiferous ducts in normal breast tissue. In breast cancer, both OATPs are highly expressed in the plasma membrane and in the cytoplasm. Since estrogen and estrogen metabolites as well as anticancer agents are substrates for OATPs these results indicate the possibility of OATP-mediated uptake of hormones during breast cancer development and an impact of certain OATPs on chemotherapeutic cancer treatment.