眼附件皮脂腺癌（OaSC）是一种侵袭性恶性肿瘤，通常需要进行眼眶切除术。其肿瘤组成和转录谱在很大程度上仍然未知，这对医学进步构成了重大障碍。在这里，我们报告了首次在单细胞分辨率下对 OaSC 进行深入的转录组分析，并辨别癌症进展的潜在机制，以发现潜在的全球免疫疗法、靶向疗法和生物标志物来指导临床管理。实验室研究与回顾性研究观察性病例系列。对 6 个患者标本进行了单细胞 RNA 测序：三个原发性肿瘤、两个具有佩吉样扩散的肿瘤和一个正常跗骨样本。通过基因签名来识别细胞成分。通过对样本之间差异表达基因进行基因本体分析，辨别了肿瘤发生和类佩吉特扩散的分子途径。对 OaSC、鳞状细胞癌 (SCC)、眼表鳞状细胞癌 (OSSN) 和基底细胞癌 (BCC) 病例的存档队列进行 CALML5 免疫组织化学分析。对 OaSC 标本中的 29,219 个细胞的分析显示肿瘤细胞、免疫细胞和基质细胞。肿瘤浸润免疫细胞包括多种细胞类型，包括耗尽的 T 细胞群。在原发性 OaSC 肿瘤中，有丝分裂核分裂和氧化磷酸化途径上调，而脂质生物合成和代谢途径下调。在经历类佩吉特扩散的肿瘤细胞中，上皮组织迁移途径上调。 scRNA-seq 分析还表明 CALML5 在 OaSC 肿瘤细胞中上调。 28 例 OaSC 病例中有 28 例 (100%) 存在弥漫性细胞核和细胞质 CALML5 染色。 25 例 SCC 和 OSSN 病例中有 5 例 (20%) 存在弥漫性核和膜 CALML5 染色，而 12 例 BCC 病例中有 1 例 (8%) 存在弥漫性核染色。这项研究揭示了复杂的 OaSC 肿瘤微环境，并证实了CALML5 免疫组织化学染色剂是一种敏感的诊断标记物。版权所有 © 2024。由 Elsevier Inc. 出版。

Ocular adnexal sebaceous carcinoma (OaSC) is an aggressive malignancy that often necessitates orbital exenteration. Its tumor composition and transcriptional profile remain largely unknown, which poses a significant barrier to medical advances. Here, we report the first in-depth transcriptomic analysis of OaSC at the single-cell resolution and discern mechanisms underlying cancer progression for the discovery of potential globe-sparing immunotherapies, targeted therapies, and biomarkers to guide clinical management.Laboratory investigation with a retrospective observational case series.Single-cell RNA sequencing was performed on six patient specimens: three primary tumors, two tumors with pagetoid spread, and a normal tarsus sample. Cellular components were identified via gene signatures. Molecular pathways underlying tumorigenesis and pagetoid spread were discerned via gene ontology analysis of the differentially expressed genes between specimens. CALML5 immunohistochemistry was performed on an archival cohort of OaSC, squamous cell carcinoma (SCC), ocular surface squamous neoplasia (OSSN), and basal cell carcinoma (BCC) cases.Analysis of 29,219 cells from OaSC specimens revealed tumor, immune, and stromal cells. Tumor-infiltrating immune cells include a diversity of cell types, including exhausted T-cell populations. In primary OaSC tumors, mitotic nuclear division and oxidative phosphorylation pathways are upregulated, while lipid biosynthesis and metabolism pathways are downregulated. Epithelial tissue migration pathways are upregulated in tumor cells undergoing pagetoid spread. scRNA-seq analyses also revealed that CALML5 is upregulated in OaSC tumor cells. Diffuse nuclear and cytoplasmic CALML5 staining was present in 28 of 28 (100%) OaSC cases. Diffuse nuclear and membranous CALML5 staining was present in 5 of 25 (20%) SCC and OSSN cases, while diffuse nuclear staining was present in 1 of 12 (8%) BCC cases.This study reveals a complex OaSC tumor microenvironment and confirms that the CALML5 immunohistochemical stain is a sensitive diagnostic marker.Copyright © 2024. Published by Elsevier Inc.