SOX2 is recognized as an oncogene in human small cell lung cancer (SCLC), which is an aggressive neuroendocrine (NE) tumor. However, the role of SOX2 in SCLC is not completely understood, and strategies to selectively target SOX2 in SCLC cells remain elusive. Here, we show, using next-generation sequencing, that SOX2 expressed in the ASCL1-high SCLC (SCLC-A) subtype cell line is dependent on ASCL1, which is a lineage-specific transcriptional factor, and is involved in NE differentiation and tumorigenesis. ASCL1 recruits SOX2, which promotes INSM1 and WNT11 expression. Immunohistochemical studies revealed that SCLC tissue samples expressed SOX2, ASCL1, and INSM1 in 18 out of the 30 cases (60%). Contrary to the ASCL1–SOX2 signaling axis controlling SCLC biology in the SCLC-A subtype, SOX2 targets distinct genes such as those related to the Hippo pathway in the ASCL1-negative, YAP1-high SCLC (SCLC-Y) subtype. Although SOX2 knockdown experiments suppressed NE differentiation and cell proliferation in the SCLC-A subtype, they did not sufficiently impair the growth of the SCLC-Y subtype cell lines in vitro and ex vivo. The present results support the importance of the ASCL1–SOX2 axis as a main subtype of SCLC, and suggest the therapeutic potential of targeting the ASCL1–SOX2 axis.
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Rodriguez E, Lilenbaum RC. Small cell lung cancer: past, present, and future. Current Oncol Rep. 2010;12:327–34.
Byers LA, Rudin CM. Small cell lung cancer: where do we go from here? Cancer. 2015;121:664–72.
Gazdar AF, Bunn PA, Minna JD. Small-cell lung cancer: what we know, what we need to know and the path forward. Nat Rev Cancer. 2017;17:765.
Rudin CM, Poirier JT, Byers LA, Dive C, Dowlati A, George J, et al. Molecular subtypes of small cell lung cancer: a synthesis of human and mouse model data. Nat Rev Cancer. 2019;19:289–97.
Ball DW, Azzoli CG, Baylin SB, Chi D, Dou S, Donis-Keller H, et al. Identification of a human achaete-scute homolog highly expressed in neuroendocrine tumors. Proc Natl Acad Sci USA. 1993;90:5648–52.
Lim JS, Ibaseta A, Fischer MM, Cancilla B, O’Young G, Cristea S, et al. Intratumoural heterogeneity generated by Notch signaling promotes small-cell lung cancer. Nature. 2017;545:360–4.
Zhang W, Girard L, Zhang YA, Haruki T, Papari-Zareei M, Stastny V, et al. Small cell lung cancer tumors and preclinical models display heterogeneity of neuroendocrine phenotypes. Transl Lung Cancer Res. 2018;7:32–49.
Augustyn A, Borromeo M, Wang T, Fujimoto J, Shao C, Dospoy PD, et al. ASCL1 is a lineage oncogene providing therapeutic targets for high-grade neuroendocrine lung cancers. Proc Natl Acad Sci USA. 2014;111:14788–93.
Borromeo MD, Savage TK, Kollipara RK, He M, Augustyn A, Osborne JK, et al. ASCL1 and NEUROD1 reveal heterogeneity in pulmonary neuroendocrine tumors and regulate distinct genetic programs. Cell Rep. 2016;16:1259–72.
Rudin CM, Durinck S, Atawiski F, Poirier JT, Modrusan Z, Shames DS, et al. Comprehensive genomic analysis identifies SOX2 as a frequently amplified gene in small-cell lung cancer. Nat Genet. 2012;44:1111–6.
Travis WD, Brambilla E, Burke AP, Marx A, Nicholson AG. WHO classification of tumours of the lung, pleura, thymus and heart. 4th ed. Lyon, France: IARC; 2015. p. 63–8.
Yoshida R, Nagata M, Nakayama H, Niimori-Kita K, Hassan W, Tanaka T, et al. The pathological significance of Notch1 in oral squamous cell carcinoma. Lab Investig. 2013;93:1068–81.
Adachi K, Nikaido I, Ohta H, Ohtsuka S, Ura H, Kadota M, et al. Context-dependent wiring of Sox2 regulatory networks for self-renewal of embryonic and trophoblast stem cells. Mol Cell. 2013;52:380–92.
Niwa H, Nakamura A, Urata M, Shirae-Kurabayashi M, Kuraku S, Russell S, et al. The evolutionally-conserved function of group B1 Sox family members confers the unique role of Sox2 in mouse ES cells. BMC Evol Biol. 2016;16:173.
Bailey TL, Boden M, Buske FA, Frith M, Grant CE, Clementi L, et al. MEME SUITE: tools for motif discovery and searching. Nucleic Acids Res. 2009;37:W202–8.
Huang DW, Sherman BT, Lempicki RA. Systematic and integrative analysis of large gene lists using DAVID bioinformatics resources. Nature Protoc. 2009;4:44–57.
Tenjin Y, Kudo S, Kubota S, Yamada T, Matsuo A, Sato Y, et al. Ascl1-induced Wnt11 regulates neuroendocrine differentiation, proliferation and E-cadherin expression in small-cell lung cancer and Wnt11 regulates small-cell lung cancer biology. Lab Investig. 2019;99:1622–35.
Ran F, Hsu PD, Wright J, Agarwala V, Scott DA, Zhang F. Genome engineering using the CRISPR-Cas9 system. Nat Protoc. 2013;8:2281–308.
Fujino K, Motooka Y, Hassan WA, Ali Abdalla MO, Sato Y, Kudoh S, et al. INSM1 is a crucial regulator of neuroendocrine differentiation in lung cancer. Am J Pathol. 2015;185:3164–77.
Kudoh S, Tenjin Y, Kameyama H, Ichimura T, Yamada T, Matsuo A, et al. Significance of achaete-scute complex homologue 1 (ASCL1) in pulmonary neuroendocrine carcinomas; rna sequence analyses using small cell lung cancer cells and ascl1-induced pulmonary neuroendocrine carcinoma cells. Histochem Cell Biol. 2020. https://doi.org/10.1007/s00418-020-01863-z.
Ito T, Kudoh S, Ichimura T, Fujino K, Hassan WA, Udaka N. Small cell lung cancer, an epithelial to mesenchymal transition (EMT)-like cancer: significance of inactive Notch signaling and expression of achaete-scute complex homologue 1. Hum Cell. 2017;30:1–10.
Jiang L, Huang J, Higgs BW, Hu Z, Xiao Z, Yao X, et al. Genomic landscape survey identifies SRSF1 as a key oncodriver in small cell lung cancer. PLoS Genet. 2016;12:e1005895.
Saito Y, Nagae G, Motoi N, Miyauchi E, Ninomiya H, Uehara H, et al. Prognostic significance of CpG island methylator phenotype in surgically resected small cell lung carcinoma. Cancer Sci. 2016;107:320–5.
Barretina J, Caponigro G, Stransky N, Venkatesan K, Margolin AA, Kim S, et al. The Cancer Cell Line Encyclopedia enables predictive modelling of anticancer drug sensitivity. Nature. 2012;483:603–7.
George J, Lim JS, Jang SJ, Cun Y, Ozretić L, Kong G, et al. Comprehensive genomic profiles of small cell lung cancer. Nature. 2015;524:47–53.
Sholl LM, Long KB, Hornick JL. Sox2 expression in pulmonary non-small cell and neuroendocrine carcinomas. Appl Immunohistochem Mol Morphol. 2010;18:55–61.
Gazdar AF, Carney DN, Nau MM, Minna JD. Characterization of variant subclasses of cell lines derived from small cell lung cancer having distinctive biochemical, morphological, and growth properties. Cancer Res. 1985;45:2924–30.
Carney DN, Gazdar AF, Bepler G, Guccion JG, Marangos PJ, Moody TW, et al. Establishment and identification of small cell lung cancer cell lines having classic and variant features. Cancer Res. 1985;45:2913–23.
Osada H, Tatematsu Y, Yatabe Y, Horio Y, Takahashi T. ASH1 gene is a specific therapeutic target for lung cancers with neuroendocrine features. Cancer Res. 2005;65:10680–5.
Osada H, Tomida S, Yatabe Y, Tatematsu Y, Takeuchi T, Murakami H, et al. Roles of achaete-scute homologue 1 in DKK1 and E-cadherin repression and neuroendocrine differentiation in lung cancer. Cancer Res. 2008;68:1647–55.
Zhang S, Li M, Ji H, Fang Z. Landscape of transcriptional deregulation in lung cancer. BMC Genom. 2018;19:435.
Ball DW. Achaete-scute homolog-1 and Notch in lung neuroendocrine development and cancer. Cancer Lett. 2004;204:159–69.
Hassan WA, Yoshida R, Kudoh S, Hasegawa K, Niimori-Kita K, Ito T. Notch1 controls cell invasion and metastasis in small cell lung carcinoma cell lines. Lung Cancer. 2014;86:304–10.
Chen S, Xu Y, Chen Y, Li X, Mou W, Wang L, et al. SOX2 gene regulates the transcriptional network of oncogenes and affects tumorigenesis of human lung cancer cells. PLoS ONE. 2012;7:e36326.
Stewart DJ. Wnt signaling pathway in non-small cell lung cancer. J Natl Cancer Inst. 2014;106:djt356.
Rapp J, Jaromi L, Kvell K, Miskei G, Pongracz JE. WNT signaling—lung cancer is no exception. Respir Res. 2017;18:167.
Meuwissen R, Linn SC, Linnoila RI, Zevenhoven J, Mooi WJ, Berns A. Introduction of small cell lung cancer by somatic inactivation of both Trp53 and Rb1 in a conditional mouse model. Cancer Cell. 2003;4:181–9.
Meder L, König K, Ozretić L, Schultheis AM, Ueckeroth F, Ade CP, et al. NOTCH, ASCL1, p53, and RB alterations define an alternative pathway driving neuroendocrine and small cell carcinomas. Int J Cancer. 2016;138:927–38.
Lázaro S, Pérez-Crespo M, Enguita AB, Hernández P, Martínez-Palacio J, Oteo M, et al. Ablating all three retinoblastoma family members in mouse lung leads to neuroendocrine tumor formation. Oncotarget. 2017;8:4373–86.
McColl K, Wildey G, Sakre N, Lipka MB, Behtaj M, Kresak A, et al. Reciprocal expression of INSM1 and YAP1 defines subgroups in small cell lung cancer. Oncotarget. 2017;8:73745–56.
Ito T, Matsubara D, Tanaka I, Makiya K, Tanei ZI, Kumagai Y, et al. Loss of YAP1 defines neuroendocrine differentiation of lung tumors. Cancer Sci. 2016;107:1527–38.
Horie M, Saito A, Ohshima M, Suzuki HI, Nagase T. YAP and TAZ modulate cell phenotype in a subset of small cell lung cancer. Cancer Sci. 2016;107:1755–66.
Gao Z, Ure K, Ding P, Nashaat M, Yuan L, Ma J, et al. The master negative regulator REST/NRSF controls adult neurogenesis by restraining the neurogenic program in quiescent stem cell. J Neurosci. 2011;31:9772–86.
Thiel G, Ekici M, Rossler OG. RE-1 silencing transcription factor (REST): a regulator of neuronal development and neuronal/endocrine function. Cell Tissue Res. 2015;359:99–109.
We thank Ms. Yuko Fukuchi and Ms. Takako Maeda for their technical assistance, the staff of LILA for their technical support, the Institute of Molecular Embryology and Genetics, Kumamoto University, for help with RNA-seq analysis. This study was partially supported by Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan (numbers 18K19480 and 20H03691), and by Aihara Pediatric and Allergy Clinic, Yokohama, Japan. This study was also supported in part by the program of the Joint Usage/Research Center for Developmental Medicine, Institute of Molecular Embryology and Genetics, Kumamoto University.
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Tenjin, Y., Matsuura, K., Kudoh, S. et al. Distinct transcriptional programs of SOX2 in different types of small cell lung cancers. Lab Invest 100, 1575–1588 (2020). https://doi.org/10.1038/s41374-020-00479-0