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Ito T. Molecular pathology of small cell lung cancer: Overview from studies on neuroendocrine differentiation regulated by ASCL1 and Notch signaling. Pathol Int 2024; 74:239-251. [PMID: 38607250 DOI: 10.1111/pin.13426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 03/20/2024] [Accepted: 03/24/2024] [Indexed: 04/13/2024]
Abstract
Pulmonary neuroendocrine (NE) cells are rare airway epithelial cells. The balance between Achaete-scute complex homolog 1 (ASCL1) and hairy and enhancer of split 1, one of the target molecules of the Notch signaling pathway, is crucial for NE differentiation. Small cell lung cancer (SCLC) is a highly aggressive lung tumor, characterized by rapid cell proliferation, a high metastatic potential, and the acquisition of resistance to treatment. The subtypes of SCLC are defined by the expression status of NE cell-lineage transcription factors, such as ASCL1, which roles are supported by SRY-box 2, insulinoma-associated protein 1, NK2 homeobox 1, and wingless-related integration site signaling. This network reinforces NE differentiation and may induce the characteristic morphology and chemosensitivity of SCLC. Notch signaling mediates cell-fate decisions, resulting in an NE to non-NE fate switch. The suppression of NE differentiation may change the histological type of SCLC to a non-SCLC morphology. In SCLC with NE differentiation, Notch signaling is typically inactive and genetically or epigenetically regulated. However, Notch signaling may be activated after chemotherapy, and, in concert with Yes-associated protein signaling and RE1-silencing transcription factor, suppresses NE differentiation, producing intratumor heterogeneity and chemoresistance. Accumulated information on the molecular mechanisms of SCLC will contribute to further advances in the control of this recalcitrant cancer.
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Grants
- 20H03691 Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan
- 18K19489 Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan
- 16590318 Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan
- 25460439 Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan
- Smoking Research Foundation, Japan
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Affiliation(s)
- Takaaki Ito
- Department of Medical Technology, Kumamoto Health Science University Faculty of Health Sciences, Kumamoto, Japan
- Department of Pathology and Experimental Medicine, Kumamoto University Graduate School of Medical Sciences, Kumamoto, Japan
- Department of Brain Morphogenesis, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan
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2
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Heeke S, Gay CM, Estecio MR, Tran H, Morris BB, Zhang B, Tang X, Raso MG, Rocha P, Lai S, Arriola E, Hofman P, Hofman V, Kopparapu P, Lovly CM, Concannon K, De Sousa LG, Lewis WE, Kondo K, Hu X, Tanimoto A, Vokes NI, Nilsson MB, Stewart A, Jansen M, Horváth I, Gaga M, Panagoulias V, Raviv Y, Frumkin D, Wasserstrom A, Shuali A, Schnabel CA, Xi Y, Diao L, Wang Q, Zhang J, Van Loo P, Wang J, Wistuba II, Byers LA, Heymach JV. Tumor- and circulating-free DNA methylation identifies clinically relevant small cell lung cancer subtypes. Cancer Cell 2024; 42:225-237.e5. [PMID: 38278149 PMCID: PMC10982990 DOI: 10.1016/j.ccell.2024.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 07/26/2023] [Accepted: 01/04/2024] [Indexed: 01/28/2024]
Abstract
Small cell lung cancer (SCLC) is an aggressive malignancy composed of distinct transcriptional subtypes, but implementing subtyping in the clinic has remained challenging, particularly due to limited tissue availability. Given the known epigenetic regulation of critical SCLC transcriptional programs, we hypothesized that subtype-specific patterns of DNA methylation could be detected in tumor or blood from SCLC patients. Using genomic-wide reduced-representation bisulfite sequencing (RRBS) in two cohorts totaling 179 SCLC patients and using machine learning approaches, we report a highly accurate DNA methylation-based classifier (SCLC-DMC) that can distinguish SCLC subtypes. We further adjust the classifier for circulating-free DNA (cfDNA) to subtype SCLC from plasma. Using the cfDNA classifier (cfDMC), we demonstrate that SCLC phenotypes can evolve during disease progression, highlighting the need for longitudinal tracking of SCLC during clinical treatment. These data establish that tumor and cfDNA methylation can be used to identify SCLC subtypes and might guide precision SCLC therapy.
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Affiliation(s)
- Simon Heeke
- Department of Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Carl M Gay
- Department of Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Marcos R Estecio
- Epigenetic and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Hai Tran
- Department of Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Benjamin B Morris
- Department of Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Bingnan Zhang
- Department of Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Ximing Tang
- Department of Translational Molecular Pathology, the University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Maria Gabriela Raso
- Department of Translational Molecular Pathology, the University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Pedro Rocha
- Medical Oncology Department, Hospital del Mar, Barcelona, Spain
| | - Siqi Lai
- Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA; Graduate School of Biomedical Sciences, The University of Texas MD Anderson Cancer Center UTHealth Houston, Houston, TX, USA
| | - Edurne Arriola
- Medical Oncology Department, Hospital del Mar, Barcelona, Spain
| | - Paul Hofman
- Laboratory of Clinical and Experimental Pathology, IHU RespirERA, Nice Hospital, University Côte d'Azur, Nice, France
| | - Veronique Hofman
- Laboratory of Clinical and Experimental Pathology, IHU RespirERA, Nice Hospital, University Côte d'Azur, Nice, France
| | - Prasad Kopparapu
- Department of Medicine, Division of Hematology and Oncology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Christine M Lovly
- Department of Medicine, Division of Hematology and Oncology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Kyle Concannon
- Department of Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Luana Guimaraes De Sousa
- Department of Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Whitney Elisabeth Lewis
- Department of Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Kimie Kondo
- Epigenetic and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Xin Hu
- Department of Genomic Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Azusa Tanimoto
- Department of Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Natalie I Vokes
- Department of Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Monique B Nilsson
- Department of Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Allison Stewart
- Department of Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Maarten Jansen
- Pulmonary Department, Ziekenhuisgroep Twente, Hengelo, the Netherlands
| | - Ildikó Horváth
- National Korányi Institute of Pulmonology, Budapest, Hungary
| | - Mina Gaga
- 7th Respiratory Medicine Department, Athens Chest Hospital, Athens, Greece
| | | | - Yael Raviv
- Department of Medicine, Pulmonology, Institute, Soroka Medical Center, Ben-Gurion University, Beer-Sheva, Israel
| | | | | | | | | | - Yuanxin Xi
- Department of Bioinformatics and Computational Biology, the University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Lixia Diao
- Department of Bioinformatics and Computational Biology, the University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Qi Wang
- Department of Bioinformatics and Computational Biology, the University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jianjun Zhang
- Department of Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA; Department of Genomic Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Peter Van Loo
- Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA; Department of Genomic Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA; The Francis Crick Institute, London, UK
| | - Jing Wang
- Department of Bioinformatics and Computational Biology, the University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Ignacio I Wistuba
- Department of Translational Molecular Pathology, the University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Lauren A Byers
- Department of Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
| | - John V Heymach
- Department of Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
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Zhu Y, Li S, Wang H, Ren W, Chi K, Wu J, Mao L, Huang X, Zhuo M, Lin D. Molecular subtypes, predictive markers and prognosis in small-cell lung carcinoma. J Clin Pathol 2023:jcp-2023-209109. [PMID: 37775262 DOI: 10.1136/jcp-2023-209109] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 09/14/2023] [Indexed: 10/01/2023]
Abstract
AIMS A new molecular subtype classification was proposed for small-cell lung carcinoma (SCLC). We aimed to further validate the classification in various SCLC patient samples using immunohistochemistry (IHC) to highlight its clinical significance. METHODS We analysed the protein expression of four subtype (achaete-scute family BHLH transcription factor 1 (ASCL1), neuronal differentiation 1 (NEUROD1), POU class 2 homeobox 3 (POU2F3) and Yes1-associated transcriptional regulator (YAP1)) and two predictive markers (delta-like ligand 3 (DLL3) and MYC) using IHC in 216 specimens from 195 SCLC patients, including 21 pairs of resected biopsy tumours. Associations among molecular subtypes, clinicopathological features and prognostic implications were also explored. RESULTS The ASCL1, NEUROD1, POU2F3, YAP1, DLL3 and MYC-positive expression rates were 70.3%, 56.9%, 14.9%, 19.0%, 75.4% and 22.6%, respectively. DLL3 expression had positive and negative associations with that of ASCL1 and POU2F3/YAP1, respectively, whereas MYC had the opposite effect. Strong associations of ASCL1 (Ρ=0.8603, p<0.0001), NEUROD1 (Ρ=0.8326, p<0.0001), POU2F3 (Ρ=0.6950, p<0.0001) and YAP1 (Ρ=0.7466, p<0.0001) expressions were detected between paired resected biopsy tumours. In addition to SCLC-A (ASCL1-dominant), SCLC-N (NEUROD1-dominant) and SCLC-P (POU2F3-dominant), unsupervised hierarchical cluster analyses identified a fourth, quadruple-negative SCLC subtype (SCLC-QN) characterised by the low expression of all four subtype-specific proteins, and 55.4% (n=108), 27.2% (n=53), 11.8% (n=23) and 5.6% (n=11) were categorised as SCLC-A, SCLC-N, SCLC-P and SCLC-QN, respectively. Significant enrichment of SCLC-P in the combined SCLC cohort was observed, and adenocarcinoma was more prevalent in SCLC-A, while large-cell neuroendocrine carcinoma was more commonly seen in SCLC-P. No survival difference was found among molecular subtypes. CONCLUSIONS Our results provide clinical insights into the diagnostic, prognostic and predictive significance of SCLC molecular subtype classifications.
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Affiliation(s)
- Yanli Zhu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Pathology, Peking University Cancer Hospital and Institute, Beijing, China
| | - Sheng Li
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department I of Thoracic Oncology, Peking University Cancer Hospital and Institute, Beijing, China
| | - Haiyue Wang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Pathology, Peking University Cancer Hospital and Institute, Beijing, China
| | - Wenhao Ren
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Pathology, Peking University Cancer Hospital and Institute, Beijing, China
| | - Kaiwen Chi
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Pathology, Peking University Cancer Hospital and Institute, Beijing, China
| | - Jianghua Wu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Pathology, Peking University Cancer Hospital and Institute, Beijing, China
| | - Luning Mao
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Pathology, Peking University Cancer Hospital and Institute, Beijing, China
| | - Xiaozheng Huang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Pathology, Peking University Cancer Hospital and Institute, Beijing, China
| | - Minglei Zhuo
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department I of Thoracic Oncology, Peking University Cancer Hospital and Institute, Beijing, China
| | - Dongmei Lin
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Pathology, Peking University Cancer Hospital and Institute, Beijing, China
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4
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Chen P, Sun C, Wang H, Zhao W, Wu Y, Guo H, Zhou C, He Y. YAP1 expression is associated with survival and immunosuppression in small cell lung cancer. Cell Death Dis 2023; 14:636. [PMID: 37752152 PMCID: PMC10522695 DOI: 10.1038/s41419-023-06053-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 08/08/2023] [Indexed: 09/28/2023]
Abstract
Immunotherapy is considered a major breakthrough in the treatment of small cell lung cancer (SCLC), although its anti-tumor efficacy is limited. With a high degree of malignancy and high heterogeneity, SCLC is difficult to treat in the clinic. A new combination strategy is urgently needed to further improve the efficacy of immunotherapy in patients with SCLC. By immunofluorescence, 100 SCLC patients in a local cohort were classified into the SCLC-A (high ASCL1 expression; n = 36), SCLC-N (high NEUROD1 expression; n = 32), SCLC-P (high POU2F3 expression; n = 14), and SCLC-Y (high YAP1 expression; n = 18) subtypes. Each SCLC molecular subtype represented different prognoses, tumor microenvironment traits, and immunotherapy sensitivities. Analysis of both the local and public cohorts suggested that the SCLC-Y subtype exhibited the worst clinical outcome (p < 0.05) when compared with other subtypes. SCLC with high YAP1 expression was characterized by high PD-L1 expression, high stromal score, T-cell functional impairment, and a close relationship with immune-related pathways. YAP1 upregulated PD-L1 expression and suppressed T cell activation, thus leading to immune evasion. In in vitro experiments, blockade of YAP1 promoted cancer cell apoptosis, immune cell proliferation, T-cell activation, and cytotoxic T-cell infiltration, thus further potentiating the efficacy of immunotherapy in patients with the SCLC-Y subtype.
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Affiliation(s)
- Peixin Chen
- Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, No 507 Zhengmin Road, Shanghai, 200433, People's Republic of China
- Tongji University, No 1239 Siping Road, Shanghai, 200433, People's Republic of China
| | - Chenglong Sun
- Radiotherapy Department, Anhui No. 2 Provincial People's Hospital, Hefei, 230041, Anhui, People's Republic of China
| | - Hao Wang
- Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, No 507 Zhengmin Road, Shanghai, 200433, People's Republic of China
- Tongji University, No 1239 Siping Road, Shanghai, 200433, People's Republic of China
| | - Wencheng Zhao
- Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, No 507 Zhengmin Road, Shanghai, 200433, People's Republic of China
- Tongji University, No 1239 Siping Road, Shanghai, 200433, People's Republic of China
| | - Yan Wu
- Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, No 507 Zhengmin Road, Shanghai, 200433, People's Republic of China
| | - Haoyue Guo
- Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, No 507 Zhengmin Road, Shanghai, 200433, People's Republic of China
- Tongji University, No 1239 Siping Road, Shanghai, 200433, People's Republic of China
| | - Caicun Zhou
- Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, No 507 Zhengmin Road, Shanghai, 200433, People's Republic of China.
| | - Yayi He
- Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, No 507 Zhengmin Road, Shanghai, 200433, People's Republic of China.
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5
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Lo YC, Rivera-Concepcion J, Vasmatzis G, Aubry MC, Leventakos K. Subtype of SCLC Is an Intrinsic and Persistent Feature Through Systemic Treatment. JTO Clin Res Rep 2023; 4:100561. [PMID: 37731627 PMCID: PMC10507151 DOI: 10.1016/j.jtocrr.2023.100561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 07/29/2023] [Accepted: 08/06/2023] [Indexed: 09/22/2023] Open
Abstract
Introduction SCLC is an aggressive malignancy with poor outcome. Most patients have disease recurrence despite treatments with multiple modalities. Subtyping of SCLC has been proposed recently, and novel agents targeting specific subtypes are actively being investigated. In this study, we evaluated the plasticity of subtypes in paired pre- and post-treatment samples. The aim was to understand possible subtype evolution after chemotherapy resistance that could lead to alternate targeted therapy strategies. Methods A total of 68 samples from 32 patients with sufficient paired specimens were identified from 1998 to 2022. ASCL1, NEUROD1, and POU2F3 immunohistochemistry studies were performed on all cases, and subtyping by predominant expression was determined. Subtype comparison in each patient was performed, and expression analysis was performed on the basis of subtypes. Results Of 32 cases, 28 (88%) had the same subtype in pre- and first post-treatment specimens. Protein expression level of subtype-specific transcription factor remained stable after chemotherapy. Two of five (40%) NEUROD1-predominant SCLC switched to ASCL1-predominant phenotype after treatment. One case had a pitfall of scoring ASCL1 on specimen with marked crushing artifacts. One case revealed the challenge of proper subtyping for samples with borderline POU2F3 expression. Conclusions Subtype of SCLC generally remains the same after acquiring chemotherapy resistance. Plasticity was observed with rare cases switching from NEUROD1-predominant to ASC1-predominant SCLC. Resubtyping is unnecessary for the consideration of novel subtype-specific targeted agents, except cases with NEUROD1-predominant subtype.
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Affiliation(s)
- Ying-Chun Lo
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Joel Rivera-Concepcion
- Department of Medical Oncology, Mayo Clinic, Rochester, Minnesota
- Current Affiliation: Department of Medical Oncology, Duke Cancer Center, Durham, North Carolina
| | - George Vasmatzis
- Department of Molecular Medicine, Mayo Clinic, Rochester, Minnesota
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6
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Neurogenin 2 and Neuronal Differentiation 1 Control Proper Development of the Chick Trigeminal Ganglion and Its Nerve Branches. J Dev Biol 2023; 11:jdb11010008. [PMID: 36810460 PMCID: PMC9953625 DOI: 10.3390/jdb11010008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 02/14/2023] [Accepted: 02/17/2023] [Indexed: 02/22/2023] Open
Abstract
The trigeminal ganglion contains the cell bodies of sensory neurons comprising cranial nerve V, which relays information related to pain, touch, and temperature from the face and head to the brain. Like other cranial ganglia, the trigeminal ganglion is composed of neuronal derivatives of two critical embryonic cell types, neural crest and placode cells. Neurogenesis within the cranial ganglia is promoted by Neurogenin 2 (Neurog2), which is expressed in trigeminal placode cells and their neuronal derivatives, and transcriptionally activates neuronal differentiation genes such as Neuronal Differentiation 1 (NeuroD1). Little is known, however, about the role of Neurog2 and NeuroD1 during chick trigeminal gangliogenesis. To address this, we depleted Neurog2 and NeuroD1 from trigeminal placode cells with morpholinos and demonstrated that Neurog2 and NeuroD1 influence trigeminal ganglion development. While knockdown of both Neurog2 and NeuroD1 affected innervation of the eye, Neurog2 and NeuroD1 had opposite effects on ophthalmic nerve branch organization. Taken together, our results highlight, for the first time, functional roles for Neurog2 and NeuroD1 during chick trigeminal gangliogenesis. These studies shed new light on the molecular mechanisms underlying trigeminal ganglion formation and may also provide insight into general cranial gangliogenesis and diseases of the peripheral nervous system.
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Miyakawa K, Miyashita N, Horie M, Terasaki Y, Tanaka H, Urushiyama H, Fukuda K, Okabe Y, Ishii T, Kuwahara N, Suzuki HI, Nagase T, Saito A. ASCL1 regulates super-enhancer-associated miRNAs to define molecular subtypes of small cell lung cancer. Cancer Sci 2022; 113:3932-3946. [PMID: 35789143 PMCID: PMC9633298 DOI: 10.1111/cas.15481] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 06/23/2022] [Accepted: 06/27/2022] [Indexed: 11/29/2022] Open
Abstract
Small cell lung cancer (SCLC) is a highly aggressive neuroendocrine tumor with dismal prognosis. Recently, molecular subtypes of SCLC have been defined by the expression status of ASCL1, NEUROD1, YAP1, and POU2F3 transcription regulators. ASCL1 is essential for neuroendocrine differentiation and is expressed in the majority of SCLC. Although previous studies investigated ASCL1 target genes in SCLC cells, ASCL1‐mediated regulation of miRNAs and its relationship to molecular subtypes remain poorly explored. Here, we performed genome‐wide profiling of chromatin modifications (H3K27me3, H3K4me3, and H3K27ac) by CUT&Tag assay and ASCL1 knockdown followed by RNA sequencing and miRNA array analyses in SCLC cells. ASCL1 could preferentially regulate genes associated with super‐enhancers (SEs) defined by enrichment of H3K27ac marking. Moreover, ASCL1 positively regulated several SE‐associated miRNAs, such as miR‐7, miR‐375, miR‐200b‐3p, and miR‐429, leading to repression of their targets, whereas ASCL1 suppressed miR‐455‐3p, an abundant miRNA in other molecular subtypes. We further elucidated unique patterns of SE‐associated miRNAs in different SCLC molecular subtypes, highlighting subtype‐specific miRNA networks with functional relevance. Notably, we found apparent de‐repression of common target genes of different miRNAs following ASCL1 knockdown, suggesting combinatorial action of multiple miRNAs underlying molecular heterogeneity of SCLC (e.g., co‐targeting of YAP1 by miR‐9 and miR‐375). Our comprehensive analyses provide novel insights into SCLC pathogenesis and a clue to understanding subtype‐dependent phenotypic differences.
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Affiliation(s)
- Kazuko Miyakawa
- Department of Respiratory Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Naoya Miyashita
- Department of Respiratory Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Masafumi Horie
- Department of Molecular and Cellular Pathology, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Japan
| | - Yasuhiro Terasaki
- Department of Analytic Human Pathology, Nippon Medical School, Tokyo, Japan
| | - Hidenori Tanaka
- Department of Molecular and Cellular Pathology, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Japan.,Department of Otorhinolaryngology-Head and Neck Surgery, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Hirokazu Urushiyama
- Department of Respiratory Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Kensuke Fukuda
- Department of Respiratory Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yugo Okabe
- Department of Respiratory Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Takashi Ishii
- Department of Respiratory Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.,Division for Health Service Promotion, The University of Tokyo, Tokyo, Japan
| | - Naomi Kuwahara
- Department of Analytic Human Pathology, Nippon Medical School, Tokyo, Japan
| | - Hiroshi I Suzuki
- Division of Molecular Oncology, Center for Neurological Diseases and Cancer, Nagoya University Graduate School of Medicine, Nagoya, Japan.,Institute for Glyco-core Research (iGCORE), Nagoya, Japan
| | - Takahide Nagase
- Department of Respiratory Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Akira Saito
- Department of Respiratory Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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8
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Megyesfalvi Z, Barany N, Lantos A, Valko Z, Pipek O, Lang C, Schwendenwein A, Oberndorfer F, Paku S, Ferencz B, Dezso K, Fillinger J, Lohinai Z, Moldvay J, Galffy G, Szeitz B, Rezeli M, Rivard C, Hirsch FR, Brcic L, Popper H, Kern I, Kovacevic M, Skarda J, Mittak M, Marko-Varga G, Bogos K, Renyi-Vamos F, Hoda MA, Klikovits T, Hoetzenecker K, Schelch K, Laszlo V, Dome B. Expression patterns and prognostic relevance of subtype-specific transcription factors in surgically resected small cell lung cancer: an international multicenter study. J Pathol 2022; 257:674-686. [PMID: 35489038 PMCID: PMC9541929 DOI: 10.1002/path.5922] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 04/10/2022] [Accepted: 04/27/2022] [Indexed: 11/17/2022]
Abstract
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.
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Affiliation(s)
- Zsolt Megyesfalvi
- Department of Thoracic Surgery, Semmelweis University and National Institute of Oncology, Budapest, Hungary.,National Koranyi Institute of Pulmonology, Budapest, Hungary.,Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Nandor Barany
- National Koranyi Institute of Pulmonology, Budapest, Hungary.,Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria.,1st Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest, Hungary
| | - Andras Lantos
- National Koranyi Institute of Pulmonology, Budapest, Hungary
| | - Zsuzsanna Valko
- National Koranyi Institute of Pulmonology, Budapest, Hungary.,Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Orsolya Pipek
- Department of Physics of Complex Systems, Eotvos Lorand University, Budapest, Hungary
| | - Christian Lang
- Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Anna Schwendenwein
- Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | | | - Sandor Paku
- 1st Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest, Hungary
| | - Bence Ferencz
- Department of Thoracic Surgery, Semmelweis University and National Institute of Oncology, Budapest, Hungary.,National Koranyi Institute of Pulmonology, Budapest, Hungary
| | - Katalin Dezso
- 1st Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest, Hungary
| | - Janos Fillinger
- National Koranyi Institute of Pulmonology, Budapest, Hungary
| | - Zoltan Lohinai
- National Koranyi Institute of Pulmonology, Budapest, Hungary
| | - Judit Moldvay
- National Koranyi Institute of Pulmonology, Budapest, Hungary.,MTA-SE NAP, Brain Metastasis Research Group, Hungarian Academy of Sciences, Budapest, Hungary
| | - Gabriella Galffy
- Torokbalint County Institute of Pulmonology, Torokbalint, Hungary
| | - Beata Szeitz
- Division of Oncology, Department of Internal Medicine and Oncology, Semmelweis University, Budapest, Hungary
| | - Melinda Rezeli
- Department of Biomedical Engineering, Lund University, Lund, Sweden
| | - Christopher Rivard
- Division of Medical Oncology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Fred R Hirsch
- Division of Medical Oncology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.,Tisch Cancer Institute, Center for Thoracic Oncology, Mount Sinai Health System, New York, NY, USA
| | - Luka Brcic
- Diagnostic and Research Institute of Pathology, Medical University of Graz, Graz, Austria
| | - Helmut Popper
- Diagnostic and Research Institute of Pathology, Medical University of Graz, Graz, Austria
| | - Izidor Kern
- University Clinic for Respiratory and Allergic Diseases Golnik, Golnik, Slovenia
| | - Mile Kovacevic
- University Clinic for Respiratory and Allergic Diseases Golnik, Golnik, Slovenia
| | - Jozef Skarda
- Institute of Clinical and Molecular Pathology, Medical Faculty, Palacky University Olomouc, Olomouc, Czech Republic.,Department of Pathology, University Hospital Ostrava and Faculty of Medicine University of Ostrava, Ostrava, Czech Republic
| | - Marcel Mittak
- Department of Surgery, University Hospital Ostrava and Faculty of Medicine University of Ostrava, Ostrava, Czech Republic
| | | | - Krisztina Bogos
- National Koranyi Institute of Pulmonology, Budapest, Hungary
| | - Ferenc Renyi-Vamos
- Department of Thoracic Surgery, Semmelweis University and National Institute of Oncology, Budapest, Hungary.,National Koranyi Institute of Pulmonology, Budapest, Hungary
| | - Mir Alireza Hoda
- Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Thomas Klikovits
- Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria.,Department of Thoracic Surgery, Klinik Floridsdorf, Vienna, Austria
| | - Konrad Hoetzenecker
- Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Karin Schelch
- Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Viktoria Laszlo
- Department of Thoracic Surgery, Semmelweis University and National Institute of Oncology, Budapest, Hungary.,Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Balazs Dome
- Department of Thoracic Surgery, Semmelweis University and National Institute of Oncology, Budapest, Hungary.,National Koranyi Institute of Pulmonology, Budapest, Hungary.,Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
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9
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Qi J, Zhang J, Liu N, Zhao L, Xu B. Prognostic Implications of Molecular Subtypes in Primary Small Cell Lung Cancer and Their Correlation With Cancer Immunity. Front Oncol 2022; 12:779276. [PMID: 35311069 PMCID: PMC8924463 DOI: 10.3389/fonc.2022.779276] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Accepted: 01/25/2022] [Indexed: 12/18/2022] Open
Abstract
Introduction Small cell lung cancer (SCLC) has recently been characterized as heterogeneous tumors due to consensus nomenclature for distinct molecular subtypes on the basis of differential expression of four transcription markers (ASCL1, NEUROD1, POU2F3, and YAP1). It is necessary to validate molecular subtype classification in primary SCLC tumors by immunohistochemical (IHC) staining and investigate its relevance to survival outcomes. Methods Using a large number of surgically resected primary SCLC tumors, we assessed the mRNA and protein levels of the four subtype markers (ASCL1, NEUROD1, POU2F3 and YAP1) in two independent cohorts, respectively. Next, molecular subtypes defined by the four subtype markers was conducted to identify the association with clinicopathologic characteristics, survival outcomes, the expression of classic neuroendocrine markers, and molecules related to tumor immune microenvironment. Results Samples were categorized into four subtypes based on the relative expression levels of the four subtype markers, yielding to ASCL1, NEUROD1, POU2F3 and YAP1 subtypes, respectively. The combined neuroendocrine differentiation features were more prevalent in either ASCL1 or NEUROD1 subtypes. Kaplan-Meier analyses found that patients with tumors of the YAP1 subtype and ASCL1 subtype obtained the best and worst prognosis on both mRNA and IHC levels, respectively. Based on multivariate Cox proportional-hazards regression model, molecular subtype classification determined by IHC was identified as an independent indicator for survival outcomes in primary SCLC tumors. Correlation analyses indicated that the four subtype markers in SCLC cancer cells were interacted with its tumor immune microenvironment. Specifically, tumors positive for YAP1 was associated with fewer CTLA4+ T cell infiltration, while more immune-inhibitory receptors (FoxP3,PD1, and CTLA4) and fewer immune-promoting receptor (CD8) were found in tumors positive for ASCL1. Conclusions We validated the new molecular subtype classification and clinical relevance on both mRNA and protein levels from primary SCLC tumors. The molecular subtypes determined by IHC could be a pre-selected effective biomarker significantly influenced on prognosis in patients with SCLC, which warrants further studies to provide better preventative and therapeutic options for distinct molecular subtypes.
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Affiliation(s)
- Jing Qi
- Department of Biochemistry and Molecular Biology, Tianjin Medical University Cancer Institute and Hospital, Key Laboratory of Cancer Prevention and Therapy, National Clinical Research Center for Cancer, Tianjin's Clinical Research Center for Cancer, Tianjin, China
| | - Jiaqi Zhang
- Department of Radiation Oncology, Tianjin Medical University Cancer Institute and Hospital, Key Laboratory of Cancer Prevention and Therapy, National Clinical Research Center for Cancer, Tianjin's Clinical Research Center for Cancer, Tianjin, China
| | - Ningbo Liu
- Department of Radiation Oncology, Tianjin Medical University Cancer Institute and Hospital, Key Laboratory of Cancer Prevention and Therapy, National Clinical Research Center for Cancer, Tianjin's Clinical Research Center for Cancer, Tianjin, China
| | - Lujun Zhao
- Department of Radiation Oncology, Tianjin Medical University Cancer Institute and Hospital, Key Laboratory of Cancer Prevention and Therapy, National Clinical Research Center for Cancer, Tianjin's Clinical Research Center for Cancer, Tianjin, China
| | - Bo Xu
- Department of Biochemistry and Molecular Biology, Tianjin Medical University Cancer Institute and Hospital, Key Laboratory of Cancer Prevention and Therapy, National Clinical Research Center for Cancer, Tianjin's Clinical Research Center for Cancer, Tianjin, China
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10
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Ito T, Kudoh S, Fujino K, Sanada M, Tenjin Y, Saito H, Nakaishi-Fukuchi Y, Kameyama H, Ichimura T, Udaka N, Kudo N, Matsuo A, Sato Y. Pulmonary Neuroendocrine Cells and Small Cell Lung Carcinoma: Immunohistochemical Study Focusing on Mechanisms of Neuroendocrine Differentiation. Acta Histochem Cytochem 2022; 55:75-83. [PMID: 35821751 PMCID: PMC9253501 DOI: 10.1267/ahc.22-00031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 04/12/2022] [Indexed: 12/03/2022] Open
Abstract
Neuroendocrine (NE) differentiation has been histochemically detected in normal and cancer tissues and cells. Immunohistochemical analyses have provided a more detailed understanding of NE biology and pathology. Pulmonary NE cells are a rare lung epithelial type, and small cell carcinoma of the lung (SCLC) is a high-grade NE tumor. Pulmonary NE and SCLC cells share common mechanisms for NE differentiation. Neural or NE cell lineage-specific transcription factors, such as achaete-scute homologue 1 (Ascl1) and insulinoma-associated protein 1 (INSM1), are crucial for the development of pulmonary NE cells, and NE differentiation is influenced by the balance between Ascl1 and the suppressive neural transcription factor, hairy-enhancer of split 1, a representative target molecule of the Notch signaling pathway. In this review, we discuss the importance of Ascl1 and INSM1 in identifying pulmonary NE and SCLC cells and introduce Ascl1-related molecules detected by comparative RNA-sequence analyses. The molecular classification of SCLC based on the expression of lineage-specific transcription or co-transcription factors, including ASCL1, NEUROD1, POU2F3, and YAP1, was recently proposed. We attempted to characterize these 4 SCLC subtypes using integrated immunohistochemical studies, which will provide insights into the molecular characteristics of these subtypes and clarify the inter- and intratumor heterogeneities of SCLC.
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Affiliation(s)
- Takaaki Ito
- Department of Medical Technology, Faculty of Health Science Kumamoto Health Science University
| | - Shinji Kudoh
- Department of Pathology and Experimental Medicine, Kumamoto University Graduate School of Medical Sciences
| | - Kosuke Fujino
- Department of Pathology and Experimental Medicine, Kumamoto University Graduate School of Medical Sciences
| | - Mune Sanada
- Department of Pathology and Experimental Medicine, Kumamoto University Graduate School of Medical Sciences
| | - Yuki Tenjin
- Department of Pathology and Experimental Medicine, Kumamoto University Graduate School of Medical Sciences
| | - Haruki Saito
- Department of Pathology and Experimental Medicine, Kumamoto University Graduate School of Medical Sciences
| | - Yuko Nakaishi-Fukuchi
- Department of Medical Technology, Faculty of Health Science Kumamoto Health Science University
| | - Hiroki Kameyama
- Department of Medical Technology, Faculty of Health Science Kumamoto Health Science University
| | | | - Naoko Udaka
- Division of Surgical Pathology, Yokohama City University Hospital
| | - Noritaka Kudo
- Department of Pathology and Experimental Medicine, Kumamoto University Graduate School of Medical Sciences
| | - Akira Matsuo
- Department of Pathology and Experimental Medicine, Kumamoto University Graduate School of Medical Sciences
| | - Younosuke Sato
- Department of Pathology and Experimental Medicine, Kumamoto University Graduate School of Medical Sciences
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11
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Inoue H, Matsushima J, Kobayashi S, Sairenchi T, Hirata H, Chida M, Ota S, Ban S, Matsumura Y. Expression of nSATB2 in Neuroendocrine Carcinomas of the Lung: Frequent Immunopositivity of Large Cell Neuroendocrine Carcinoma with a Diagnostic Pitfall. Int J Surg Pathol 2021; 30:151-159. [PMID: 34913369 DOI: 10.1177/10668969211065757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Small cell lung carcinoma (SCLC) and pulmonary large cell neuroendocrine carcinoma (LCNEC) are both classified as lung neuroendocrine carcinoma (NEC). It has recently been reported that the special AT-rich sequence-binding protein 2 (STAB2), known as a colorectal cancer marker, is also expressed in NECs occurring in various organs including the lung. However, few studies have examined any differences of SATB2 immunopositivity between SCLC and LCNEC. We investigated SATB2 expression in 45 SCLC and 14 LCNEC cases using immunohistochemistry as well as the expression of caudal-type homeobox 2 (CDX2) and keratin (KRT) 20. The LCNEC cases were more frequently positive for SATB2 (ten out of 14, 71%) than the SCLC ones (seventeen out of 45, 38%) with a statistically significance (P = 0.035). Furthermore, two LCNEC cases were positive for CDX2 while no positive findings were observed for any SCLC cases, the difference of which, however, was not statistically significant (P = 0.053). KRT20 was negative in all LCNEC and SCLC cases. These results require our attention when we use SATB2 and CDX2 as colorectal cancer markers because their expression in pulmonary NECs can lead to a misdiagnosis that the tumor is of metastatic colorectal adenocarcinoma, especially when the patient has a past history of colorectal cancer. Analyzing the relationship between the demographic/clinical variables and the SATB2 expression in the SCLC cases, just high Brinkman index (≥ 600) was significantly related to the positivity of SATB2 (P = 0.017), which is interesting considering the strong relationship between SCLC and smoking.
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Affiliation(s)
- Hiromichi Inoue
- 26263Dokkyo Medical University Saitama Medical Center, Koshigaya, Japan
| | - Jun Matsushima
- 26263Dokkyo Medical University Saitama Medical Center, Koshigaya, Japan
| | - Satoru Kobayashi
- 26263Dokkyo Medical University Saitama Medical Center, Koshigaya, Japan
| | | | - Hirokuni Hirata
- 26263Dokkyo Medical University Saitama Medical Center, Koshigaya, Japan
| | | | - Satoshi Ota
- 37009Teine Keijinkai Hospital, Sapporo, Japan
| | - Shinichi Ban
- 26263Dokkyo Medical University Saitama Medical Center, Koshigaya, Japan
| | - Yuji Matsumura
- 26263Dokkyo Medical University Saitama Medical Center, Koshigaya, Japan
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12
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El Sayed R, Blais N. Immunotherapy in Extensive-Stage Small Cell Lung Cancer. Curr Oncol 2021; 28:4093-4108. [PMID: 34677265 PMCID: PMC8534845 DOI: 10.3390/curroncol28050347] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 09/30/2021] [Accepted: 10/01/2021] [Indexed: 01/22/2023] Open
Abstract
Small cell lung cancer (SCLC) remains a poorly understood disease with aggressive features, high relapse rates, and significant morbidity as well as mortality, yet persistently limited treatment options. For three decades, the treatment algorithm of SCLC has been stagnant despite multiple attempts to find alternative therapeutic options that could improve responses and increase survival rates. On the other hand, immunotherapy has been a thriving concept that revolutionized treatment options in multiple malignancies, rendering previously untreatable diseases potentially curable. In extensive stage SCLC, immunotherapy significantly altered the course of disease and is now part of the treatment algorithm in the first-line setting. Nevertheless, the important questions that arise are how best to implement immunotherapy, who would benefit the most, and finally, how to enhance responses.
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Affiliation(s)
| | - Normand Blais
- Centre Hospitalier de Université de Montreal, Montreal, QC H2X 0C1, Canada;
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