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

摘要 赖氨酸特异性脱甲基酶1（LSD 1）是一种核组蛋白脱甲基酶。我们的工作表明，LSD 1表达 在临床口腔鳞状细胞癌（OSCC）中，随着肿瘤分级和分期而进行性增加。我们长久以来- 长期目标是基于对LSD 1在进行性口腔恶性肿瘤中的作用机制的初步研究， 治疗应用。最近的初步研究表明，舌中的条件性LSD 1缺失 在异型增生过程中，上皮细胞减少了浸润性病理损伤，下调了EGFR、YAP诱导的信号传导 网络和Pd-L1表达。其次，在异型增生期间局部应用LSD 1抑制剂可以防止其在非典型增生中的作用。 进展为侵袭性表型、减弱的病理损伤、Hippo信号传导效应物的表达（雅普， Taz，Ccn 2，）和免疫检查点（Pd-1和Pd-l1）。LSD 1抑制剂使OSCC对与 雅普抑制剂、抗PD-1或抗PD-L1抗体，限制体内肿瘤进展。因此，我们展示了 阻断LSD 1首次抑制了癌前病变，在肿瘤进展过程中形成了一个前馈回路。 口腔鳞状细胞癌有趣的是，LSD 1抑制减弱了在两个细胞中鉴定的IL-6-JAK-STAT 3新信号传导。 独立研究1）LSD敲除小鼠肿瘤前的蛋白质组学分析和2）单细胞RNAseq 使用LSD 1抑制剂分析。然而，LSD 1的功能机制，其在进行性口腔溃疡中的靶细胞， LSD 1如何促进IL-6-JAK-STAT 3的表达仍不清楚。这种知识差距阻碍了 针对OSCC设计有效的新表观遗传治疗策略。我们假设（1）LSD 1 在发育异常期间的上调通过作用于IL 6信号传导将口腔组织重编程为侵袭性表型， 诱导的细胞类型和（2）LSD 1重置表观基因组的药理学衰减，以逆转进行性 恶性肿瘤前病变转变为非侵袭性表型。使用临床相关的动物模型，该项目是很好的- 定位于解决以下具体目的：1）确定如何上调LSD 1表观遗传 在进行性口腔癌前病变侵袭表型期间重编程异型增生以促进IL 6网络; 2） 确定LSD 1是否与雅普协同促进IL 6-JAK-STAT 3网络诱导的侵袭表型， 癌前病变，和3）确定药理学LSD 1抑制逆转的翻译重要性 通过抑制IL 6-JAK-STAT 3信号传导诱导的癌症干细胞和免疫细胞的癌前病变。成功 完成拟议的项目，预计将确定LSD 1和治疗应用机制， IL 6-JAK-STAT 3网络、相关干细胞和免疫细胞。最后，该研究将确定LSD 1是否具有 在抗PD-1免疫疗法抗性和药理学LSD 1抑制中， 在兽医和人类医学中的潜在应用。总的来说，这项研究将对未来产生更广泛的影响。 在人类癌前病变中的转化研究。

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.