胰岛素瘤相关蛋白 1 (INSM1) 是最近发现的一种神经内分泌标记物，是一种转录调节因子，在不同物种中具有高度保守的 INSM1 同源物。本研究研究了 INSM1 抗体在来自不同解剖位置的 20 个正常犬神经内分泌组织、87 个神经内分泌来源的增生或肿瘤组织以及 62 个非神经内分泌肿瘤中的免疫组织化学反应性，并将结果与​​神经内分泌肿瘤中嗜铬粒蛋白 A 和突触素的结果进行了比较。对新鲜的犬垂体和犬甲状旁腺进行蛋白质印迹以确认抗 INSM1 抗体的特异性。结果显示，抗INSM1抗体可以在除甲状旁腺外的正常犬神经内分泌组织中检测到核表达。 INSM1 在 79/87 (91%) 的增生性和肿瘤性神经内分泌病变中可检测到，但所有甲状旁腺癌和甲状旁腺腺瘤（各三个样本）的 INSM1 均为阴性。相比之下，INSM1 仅在 62 种非神经内分泌肿瘤中的一种 (2%) 中检测到。所有三种标记物免疫标记呈阳性的神经内分泌肿瘤的总体百分比为 89%。此外，INSM1 的核表达比嗜铬粒蛋白 A 或突触素的核表达更容易解释。这些发现证实，INSM1 是诊断犬神经内分泌肿瘤（甲状旁腺肿瘤除外）的有用免疫组织化学标记物，应被视为免疫组织化学组合的一部分，以提高诊断能力。

Insulinoma-associated protein 1 (INSM1), a recently identified neuroendocrine marker, is a transcriptional regulator with highly conserved INSM1 homologues in various species. This study investigated the immunohistochemical reactivity of the INSM1 antibody in 20 normal canine neuroendocrine tissues from various anatomical locations, 87 hyperplastic or neoplastic tissues of neuroendocrine origin, and 62 non-neuroendocrine neoplasms and compared the results with those of chromogranin A and synaptophysin in neuroendocrine neoplasms. Western blot was performed on fresh canine pituitary glands and canine parathyroid glands to confirm the specificity of the anti-INSM1 antibody. The results showed that the anti-INSM1 antibody could detect nuclear expression in normal canine neuroendocrine tissues, except for the parathyroid glands. INSM1 was detectable in 79/87 (91%) of the hyperplastic and neoplastic neuroendocrine lesions, but all parathyroid carcinomas and parathyroid adenomas (three samples each) were negative for INSM1. In contrast, INSM1 was detected in only one of 62 (2%) non-neuroendocrine neoplasms. The overall percentage of neuroendocrine neoplasms that immunolabeled positively for all three markers was 89%. In addition, the nuclear expression of INSM1 was easier to interpret than that of chromogranin A or synaptophysin. These findings confirm that INSM1 is a useful immunohistochemical marker for diagnosing canine neuroendocrine neoplasms, except for parathyroid neoplasms, and should be considered as part of immunohistochemistry panels to improve diagnostic capability.