Mechanism of LSD1 Function and Its Therapeutic Application for Progressive Oral Malignancy

摘要 赖氨酸特异性去甲基酶1(LSD1)是一种核型组蛋白去甲基酶。我们的工作表明，LSD1表达式 临床口腔鳞状细胞癌(OSCC)随着肿瘤分级和分期的增加而递增。我们的长- 学期目标是评估LSD1在进展性口腔恶性肿瘤中的作用机制，其基础是 治疗应用。最近的初步研究表明，舌头中的条件性LSD1缺失 异型增生中的上皮减少侵袭性病理损害，下调EGFR，YAP诱导的信号转导 网络和PD-L1的表达。其次，在不典型增生期间局部应用LSD1抑制剂可以防止其 进展为侵袭性表型、减轻的病理损害、Hippo信号效应分子(YAP， Taz、Ccn2)和免疫检查点(PD-1和PD-L1)。LSD1抑制剂增敏口腔鳞状细胞癌与 YAP抑制剂、抗PD-1或抗PD-L1抗体，限制体内肿瘤的进展。因此，我们展示了 阻断LSD1第一次抑制了创业，这是在肿瘤进展过程中的一个前馈环路 口腔鳞状细胞癌的异型增生。有趣的是，LSD1抑制减弱了IL-6-JAK-STAT3新信号转导 独立研究1)LSD基因敲除小鼠创业的蛋白质组学分析2)单细胞RNAseq 使用LSD1抑制剂进行分析。然而，LSD1的作用机制及其靶细胞在进展性口腔疾病中的作用 恶性肿瘤，以及LSD1如何促进IL-6-JAK-STAT3仍不清楚。这一知识鸿沟阻止了 有针对性地设计有效的口腔鳞癌新的表观遗传学治疗策略。我们假设(1)LSD1 异型增生中的上调通过作用于IL6信号和 诱导的细胞类型和(2)LSD1重置表观基因组逆转进展的药理学衰减 恶性癌变为非侵袭性表型。使用临床相关的动物模型，这个项目很好地- 定位于解决以下具体目标：1)确定LSD1如何在表观遗传学上上调 在进行性口腔癌侵袭性表型期间重新编程异型以促进IL6网络；2) 确定LSD1是否与YAP协同促进IL6-JAK-STAT3网络诱导的侵袭性表型 3)确定药物性LSD1抑制逆转的翻译重要性 通过抑制IL6-JAK-STAT3信号诱导的肿瘤干细胞和免疫细胞的癌变。成功者 拟议项目的完成预计将确定LSD1和治疗应用机制 IL6-JAK-STAT3网络、相关干细胞和免疫细胞。最后，这项研究将确定LSD1是否起到了作用 在抗PD-1免疫治疗中，抵抗和药物抑制LSD1可以减轻猫口腔鳞癌的持续时间 在兽医和人类医学方面的潜在应用。总体而言，这项研究将对未来产生更广泛的影响 人类创业症的翻译研究。

Abstract Lysine-specific demethylase 1 (LSD1) is a nuclear histone demethylase. Our work shows that LSD1 expression progressively increases with tumor grade and stage in clinical oral squamous cell carcinoma (OSCC). Our long- term goal is to evaluate LSD1 mechanism in progressive oral malignancy based on preliminary studies for therapeutic applications. Recent preliminary studies showed that conditional LSD1 deletion in the tongue epithelium during dysplasia reduced invasive pathological lesions, downregulated EGFR, YAP-induced signaling network, and Pd-L1 expression. Next, the topical application of LSD1 inhibitor during dysplasia prevented its progression to invasive phenotype, attenuated pathological lesions, expression of Hippo signaling effectors (Yap, Taz, Ccn2,) and immune checkpoints (Pd-1, and Pd-l1). LSD1 inhibitor sensitized OSCC to combinations with either YAP inhibitor, anti-PD-1, or anti-PD-L1 antibodies, limiting tumor progression in vivo. Thus, we showed for the first time that blocking LSD1 inhibits preneoplasia, a feed-forward loop during the progression of dysplasia to OSCC. Interestingly, LSD1 inhibition attenuates IL-6-JAK-STAT3 novel signaling identified in two independent studies 1) proteomics analysis of LSD knockout mice preneoplasia and 2) single-cell RNAseq analysis using LSD1 inhibitor. However, the mechanism of LSD1 function, its target cells in progressive oral malignancy, and how LSD1 promotes IL-6-JAK-STAT3 remain unclear. This knowledge gap prevents the targeted design of effective new epigenetic therapeutic strategies for OSCC. We hypothesize that (1) LSD1 upregulation during dysplasia reprograms oral tissue to invasive phenotype by acting on IL6 -signaling and induced cell types and (2) pharmacological attenuation of LSD1 reset epigenome to reverse progressive malignant preneoplasia to a noninvasive phenotype. Using clinically relevant animal models, this project is well- positioned to address the following Specific Aims: 1) to determine how upregulated LSD1 epigenetically reprogram dysplasia to promote IL6 network during progressive oral preneoplasia invasive phenotype; 2) to determine if LSD1 collaborates with YAP to promote IL6-JAK-STAT3 network induced invasive phenotype in preneoplasia, and 3) to determine the translational importance of pharmacological LSD1 inhibition reverse preneoplasia by inhibiting IL6-JAK-STAT3 signaling induced cancer stem and immune cells. The successful completion of the proposed project is expected to identify LSD1 and therapeutic application mechanisms in the IL6-JAK-STAT3 network, related stem cells, and immune cells. Finally, the study will determine if LSD1 a role in anti-PD-1 immunotherapy resistance and pharmacological LSD1 inhibition can attenuate feline OSCC for a potential application in veterinary and human medicine. Overall, the study will have a broader impact on future translational studies in human preneoplasia.