POU2F3-expressing intraepithelial small-cell carcinoma with mixed small-cell carcinoma and conventional-type urothelial carcinoma of the urinary bladder.

Based on lineage-specific transcription factors, small-cell neuroendocrine carcinoma (SmCC) of the urinary bladder has recently been subtyped into three molecular subtypes: ASCL1, NEUROD1 and POU2F3. The latter is a master transcriptional regulator of tuft cells (TCs) which are rare solitary cells found in various mucosal epithelia such as the gastrointestinal tract, but which have not been reported in the bladder. The POU2F3 subtype shows low or absent neuroendocrine marker expression.

Molecular and Pathologic Characterization of YAP1-Expressing Small Cell Lung Cancer Cell Lines Leads to Reclassification as SMARCA4-Deficient Malignancies.

Purpose: The classification of small cell lung cancer (SCLC) into distinct molecular subtypes defined by ASCL1, NEUROD1, POU2F3, or YAP1 (SCLC-A, -N, -P, or -Y) expression, paves the way for a personalized treatment approach. However, the existence of a distinct YAP1-expressing SCLC subtype remains controversial.

Experimental Design: To better understand YAP1-expressing SCLC, the mutational landscape of human SCLC cell lines was interrogated to identify pathogenic alterations unique to SCLC-Y.

Immunohistochemical evaluation of the prognostic and predictive power of epidermal growth factor receptor ligand levels in patients with metastatic colorectal cancer.

For patients with metastatic colorectal cancer (mCRC), epidermal growth factor receptor (EGFR) inhibitors are limited to patients with wild-type tumours. Not all patients will benefit from treatment and better predictive biomarkers are needed. Here we investigated the prognostic and predictive impact of the EGFR ligands amphiregulin (AREG) and epiregulin (EREG).

Proliferative Glomerulonephritis With Fibrils, Monoclonal κ Light Chain, and C3 Deposits.

There is increasing recognition of monoclonal gammopathy as a cause of proliferative glomerulonephritis (GN), including cases in which glomerular deposition of monoclonal immunoglobulin is demonstrated. Recently, proliferative GN with monoclonal immunoglobulin deposits (PGNMID) has incorporated a light chain variant of the disease (termed PGNMID-LC). Intriguingly, glomerular co-deposition of C3 is found in addition to monotypic light chain, implying complement activation via the alternative pathway (AP).