Department of Veterinary Medicine, School of Veterinary Medicine, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei, 106319, Taiwan (ROC).
Animal Cancer Treatment Center, National Taiwan University Veterinary Hospital, National Taiwan University, No. 153, Sec. 3, Keelung Road, Taipei, 106328, Taiwan (ROC).
BMC Vet Res. 2024 Nov 29;20(1):537. doi: 10.1186/s12917-024-04385-1.
YKL-40, a secretory glycoprotein, is involved in tumor cell proliferation, metastasis, and angiogenesis in human cancers. Its overexpression has been correlated with unfavorable prognosis in many human cancers. In veterinary medicine, elevated YKL-40 levels in the serum of canine cutaneous mast cell tumors (cMCTs) were observed in our previous study. However, the expression pattern of YKL-40 in canine cMCT tissues, along with its association with clinical and pathological features, is still unknown. This study aims to retrospectively investigate the expression level of YKL-40 in the tissues of canine cMCTs and its correlation with clinical features, pathological characteristics, and clinical outcomes. Forty formalin-fixed paraffin-embedded cMCT tissues collected from forty dogs were diagnosed as low-grade (n = 20) or high-grade s(n = 20) MCT according to the Kiupel grading system. The expression level of YKL-40 in cMCT tissues was investigated using immunohistochemical staining and immunoreactivity score (IRS).
YKL-40 was expressed in all cMCTs at different levels, with significantly stronger expression in low-grade cMCTs compared to high-grade cMCTs. The expression level was also associated with tumor diameter, histological grade, mitotic counts, vessel density, and survival of cMCTs. The overall survival of cMCT dogs showed significant differences (p < 0.01) among mild (n = 15, MST 219 days), moderate (n = 19, MST not reached), and high (n = 6, MST not reached) YKL-40 expression groups. Among low-grade cMCTs, overall survival was significantly different between mild YKL-40 expression (MST 319 days) and moderate to high YKL-40 (MST not reached) expression (p < 0.01). In high-grade cMCTs, overall survival was not correlated with YKL-40 expression (p = 0.6589).
This study found that the YKL-40 expression level was significantly stronger in low-grade than in high-grade canine cutaneous mast cell tumors and was associated with various clinical and pathological features. Stronger YKL-40 expression level correlated with longer survival time, especially in low-grade cMCTs. Therefore, YKL-40 could serve as a prognostic marker for cMCTs.
YKL-40 是一种分泌型糖蛋白，参与人类癌症中的肿瘤细胞增殖、转移和血管生成。其过表达与许多人类癌症的不良预后相关。在兽医领域，我们之前的研究观察到犬皮肤肥大细胞瘤（cMCT）患者血清中 YKL-40 水平升高。然而，YKL-40 在犬 cMCT 组织中的表达模式及其与临床和病理特征的关系尚不清楚。本研究旨在回顾性研究 YKL-40 在犬 cMCT 组织中的表达水平及其与临床特征、病理特征和临床结果的相关性。从 40 只患有 cMCT 的犬中收集了 40 例福尔马林固定石蜡包埋的 cMCT 组织，根据 Kiupel 分级系统将其诊断为低级别（n=20）或高级别（n=20）MCT。使用免疫组织化学染色和免疫反应评分（IRS）检测 cMCT 组织中 YKL-40 的表达水平。
YKL-40 在所有 cMCT 中均以不同水平表达，低级别 cMCT 的表达明显强于高级别 cMCT。表达水平还与肿瘤直径、组织学分级、有丝分裂计数、血管密度和 cMCT 的生存有关。cMCT 犬的总生存率在 YKL-40 轻度表达（n=15，MST 219 天）、中度表达（n=19，MST 未达到）和高表达（n=6，MST 未达到）组之间有显著差异（p<0.01）。在低级别 cMCT 中，YKL-40 轻度表达（MST 319 天）和中度至高度 YKL-40 表达（MST 未达到）之间的总生存率有显著差异（p<0.01）。在高级别 cMCT 中，YKL-40 表达与总生存率无关（p=0.6589）。
本研究发现，YKL-40 在低级别犬皮肤肥大细胞瘤中的表达明显强于高级别，与各种临床和病理特征相关。较强的 YKL-40 表达水平与较长的生存时间相关，特别是在低级别 cMCT 中。因此，YKL-40 可作为 cMCT 的预后标志物。
