Mammary-like adenocarcinoma of the vulva: a rare case report with next generation sequencing.

Vulvar adenocarcinomas are rare tumors, representing approximately 5% of vulvar cancers. Mammary-like adenocarcinomas of the vulva (MLAV) are extremely rare, and their molecular features are poorly described in the scientific literature. We report a case of an 88-year-old woman affected by MLAV with comedo-like features, with a detailed description of the pathological, immunohistochemical and molecular features. Immunohistochemistry (IHC) showed strong staining for cytokeratin 7, GATA3, androgen receptor, GCFPD15, and weak staining for mammaglobin; no staining for Her-2 was found. The proliferation index (Ki-67) was 15%. Molecular testing detected a pathogenic mutation of the AKT1 gene, a likely pathogenic frameshift insertion of the JAK1 gene, and two likely pathogenic frameshift deletions of the KMT2C gene; in addition, two variants of unknown significance (VUS) involving the ARID1A and OR2T4 genes were detected. Finally, two CNVs of the BRCA1 gene were identified.

Crystal structure of the Menglà virus VP30 C-terminal domain.

The family Filoviridae contains many important human viruses, including Marburg virus (MARV) and Ebola virus (EBOV). Menglà virus (MLAV), a newly discovered filovirus, is considered a potential human pathogen. The VP30 C-terminal domain (CTD) of these filoviruses plays an essential role in virion assembly. In common with other filoviruses, MLAV VP30 CTD mainly exists as a dimer in solution. In this work, we determined the crystal structure of recombinant MLAV VP30 CTD monomer, verifying that C-terminal helix-7 (H7) is critical for the dimerization process. This study provides a preliminary model for investigation of MLAV VP30 CTD as an anti-filovirus drug development target.

Development of a Menglà virus minigenome and comparison of its polymerase complexes with those of other filoviruses.

Ebola virus (EBOV) and Marburg virus (MARV), members of the Filoviridae family, are highly pathogenic and can cause hemorrhagic fevers, significantly impacting human society. Bats are considered reservoirs of these viruses because related filoviruses have been discovered in bats. However, due to the requirement for maximum containment laboratories when studying infectious viruses, the characterization of bat filoviruses often relies on pseudoviruses and minigenome systems. In this study, we used RACE technology to sequence the 3'-leader and 5'-trailer of Menglà virus (MLAV) and constructed a minigenome. Similar to MARV, the transcription activities of the MLAV minigenome are independent of VP30. We further assessed the effects of polymorphisms at the 5' end on MLAV minigenome activity and identified certain mutations that decrease minigenome reporter efficiency, probably due to alterations in the RNA secondary structure. The reporter activity upon recombination of the 3'-leaders and 5'-trailers of MLAV, MARV, and EBOV with those of the homologous or heterologous minigenomes was compared and it was found that the polymerase complex and leader and trailer sequences exhibit intrinsic specificities. Additionally, we investigated whether the polymerase complex proteins from EBOV and MARV support MLAV minigenome RNA synthesis and found that the homologous system is more efficient than the heterologous system. Remdesivir efficiently inhibited MLAV as well as EBOV replication. In summary, this study provides new information on bat filoviruses and the minigenome will be a useful tool for high-throughput antiviral drug screening.