BACKGROUND: Profiling studies in small-cell lung cancer (SCLC) have mainly focused on primary tumors, omitting the potential molecular changes that might occur during lymphatic metastasis formation. Here, we assessed the molecular discordance between primary SCLCs and corresponding lymph node (LN) metastases in the light of subtype distribution and expression of clinically relevant proteins. METHODS: Comparative profiling of 32 surgically resected primary SCLCs and their LN metastases was achieved by RNA expression analysis and immunohistochemistry (IHC). In addition to subtype markers (ASCL1, NEUROD1, POU2F3, and YAP1), the expression of nine cancer-specific proteins was evaluated. RESULTS: The selected clinically relevant molecules showed no significant differences in their RNA expression profile when assessing the primary tumors and their corresponding LN metastases. Nevertheless, IHC analyses revealed significantly higher DLL3 expression in the primary tumors than in the LN metastases (P = 0.008). In contrast, NEUROD1 expression was significantly lower in the primary tumors (versus LN metastases, P < 0.001). No statistically significant difference was found by IHC analysis in the case of other clinically relevant proteins. Concerning SCLC molecular subtypes, a change in subtype distribution was detected in 21 cases. Phenotype switching from neuroendocrine (NE) subtypes toward non-NE lesions and from non-NE landscape toward NE subtypes were both detected. CONCLUSIONS: Although the molecular landscape of SCLC LN metastases largely resembles that of the tumor of origin, key differences exist in terms of DLL3 and NEUROD1 expression, and in subtype distribution. These diagnostic pitfalls should be considered when establishing the tumors' molecular profile for future clinical trials solely based on LN biopsies.

• MeSH
• imunohistochemie MeSH
• lidé středního věku MeSH
• lidé MeSH
• lymfatické metastázy * patologie   MeSH
• malobuněčný karcinom plic * chirurgie   patologie   genetika   MeSH
• nádorové biomarkery genetika   MeSH
• nádory plic * patologie   chirurgie   genetika   MeSH
• senioři MeSH
• transkripční faktory bHLH genetika   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH

BACKGROUND: Advancements in immunotherapeutic approaches only had a modest impact on the therapy of lung neuroendocrine neoplasms (LNENs). Our multicenter study aimed to investigate the expression patterns of novel immunotherapy targets in intermediate- and high-grade LNENs. METHODS: The expressions of V-domain Ig suppressor of T cell activation (VISTA), OX40L, Glucocorticoid-induced TNF receptor (GITR), and T cell immunoglobulin and mucin domain 3 (TIM3) proteins were measured by immunohistochemistry in surgically resected tumor samples of 26 atypical carcinoid (AC), 49 large cell neuroendocrine lung cancer (LCNEC), and 66 small cell lung cancer (SCLC) patients. Tumor and immune cells were separately scored. RESULTS: Tumor cell TIM3 expression was the highest in ACs (p < 0.001), whereas elevated tumor cell GITR levels were characteristic for both ACs and SCLCs (p < 0.001 and p = 0.011, respectively). OX40L expression of tumor cells was considerably lower in ACs (vs. SCLCs; p < 0.001). Tumor cell VISTA expression was consistently low in LNENs, with no significant differences across histological subtypes. ACs were the least immunogenic tumors concerning immune cell abundance (p < 0.001). Immune cell VISTA and GITR expressions were also significantly lower in these intermediate-grade malignancies than in SCLCs or in LCNECs. Immune cell TIM3 and GITR expressions were associated with borderline prognostic significance in our multivariate model (p = 0.057 and p = 0.071, respectively). CONCLUSIONS: LNEN subtypes have characteristic and widely divergent VISTA, OX40L, GITR, and TIM3 protein expressions. By shedding light on the different expression patterns of these immunotherapy targets, the current multicenter study provides support for the future implementation of novel immunotherapeutic approaches.

• MeSH
• antigeny B7 metabolismus   MeSH
• buněčný receptor 2 viru hepatitidy A * metabolismus   MeSH
• dospělí MeSH
• glukokortikoidy indukovaný protein související s TNRF * metabolismus   MeSH
• imunoterapie * metody   MeSH
• lidé středního věku MeSH
• lidé MeSH
• ligand OX40 metabolismus   MeSH
• nádorové biomarkery * metabolismus   MeSH
• nádory plic * imunologie   patologie   terapie   metabolismus   MeSH
• neuroendokrinní nádory * imunologie   metabolismus   terapie   patologie   MeSH
• prognóza MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• stupeň nádoru MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH

The tissue distribution and prognostic relevance of subtype-specific proteins (ASCL1, NEUROD1, POU2F3, YAP1) present an evolving area of research in small-cell lung cancer (SCLC). The expression of subtype-specific transcription factors and P53 and RB1 proteins were measured by immunohistochemistry (IHC) in 386 surgically resected SCLC samples. Correlations between subtype-specific proteins and in vitro efficacy of various therapeutic agents were investigated by proteomics and cell viability assays in 26 human SCLC cell lines. Besides SCLC-A (ASCL1-dominant), SCLC-AN (combined ASCL1/NEUROD1), SCLC-N (NEUROD1-dominant), and SCLC-P (POU2F3-dominant), IHC and cluster analyses identified a quadruple-negative SCLC subtype (SCLC-QN). No unique YAP1-subtype was found. The highest overall survival rates were associated with non-neuroendocrine subtypes (SCLC-P and SCLC-QN) and the lowest with neuroendocrine subtypes (SCLC-A, SCLC-N, SCLC-AN). In univariate analyses, high ASCL1 expression was associated with poor prognosis and high POU2F3 expression with good prognosis. Notably, high ASCL1 expression influenced survival outcomes independently of other variables in a multivariate model. High POU2F3 and YAP1 protein abundances correlated with sensitivity and resistance to standard-of-care chemotherapeutics, respectively. Specific correlation patterns were also found between the efficacy of targeted agents and subtype-specific protein abundances. In conclusion, we investigated the clinicopathological relevance of SCLC molecular subtypes in a large cohort of surgically resected specimens. Differential IHC expression of ASCL1, NEUROD1, and POU2F3 defines SCLC subtypes. No YAP1-subtype can be distinguished by IHC. High POU2F3 expression is associated with improved survival in a univariate analysis, whereas elevated ASCL1 expression is an independent negative prognosticator. Proteomic and cell viability assays of human SCLC cell lines revealed distinct vulnerability profiles defined by transcription regulators. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

• MeSH
• lidé MeSH
• malobuněčný karcinom plic * genetika   metabolismus   chirurgie   MeSH
• nádorové buněčné linie MeSH
• nádory plic * genetika   metabolismus   chirurgie   MeSH
• prognóza MeSH
• proteomika MeSH
• regulace genové exprese u nádorů MeSH
• transkripční faktory bHLH genetika   metabolismus   MeSH
• transkripční faktory genetika   metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• práce podpořená grantem MeSH