University of Veterinary Medicine Vienna (Vetmeduni), Veterinaerplatz 1, Vienna, Austria.
Division of Neurological Sciences, Vetsuisse Faculty, University of Bern, Bremgartenstrasse 109a, 3012, Bern, Switzerland.
Vet Med Sci. 2024 Jul;10(4):e1537. doi: 10.1002/vms3.1537.
The standard treatment for canine and feline meningiomas includes radiotherapy, surgical excision or combined therapy. However, new therapeutic approaches are required due to the possible recurrence or progression of meningiomas despite initial therapy. Adjunctive therapy with synthetic long-acting somatostatin (SST) analogues has been described in humans with SST-expressing tumours. The expression of SST receptors (SSTRs) by feline meningiomas is currently unknown, and there are little data about canine meningiomas. We hypothesized that SSTR is expressed by canine and feline meningiomas (S1).
Seven canines and 11 felines with histologically confirmed meningiomas underwent STTR screening. RNA expressions of SSTR1, SSTR2, SSTR3 and SSTR5 (canine) and SSTR1-SSTR 5 (feline) in fresh frozen and formalin-fixed and paraffin-embedded (FFPE) samples were investigated using real-time (RT)-qPCR. The expression of SSTR1 and SSTR2 in FFPE samples was evaluated using immunohistochemistry (IHC). The specificity of applied antibodies for canine and feline species was confirmed by western blotting.
In canine meningiomas (n = 7), RNA expression of SSTR1, SSTR2 and SSTR5 was detected in all samples; SSTR3 RNA expression was detected in only 33% of samples. In feline meningiomas (n = 12), RNA expression of SSTR1, SSTR4, SSTR5 and SSTR2 was detected in 91%, 46%, 46% and 36% of samples, respectively; SSTR3 was not expressed. Overall, the detection rate was lower in FFPE samples. IHC revealed the expression of SSTR1 and SSTR2 in all samples from both species. However, it is important to exercise caution when interpreting IHC results due to the presence of diffuse background staining.
SSTRs are widely expressed in canine and feline meningiomas, thereby encouraging further studies investigating SSTR expression to conduct trials about the effect of adjunctive therapy with long-acting SST-analogues.
犬猫脑膜瘤的标准治疗包括放疗、手术切除或联合治疗。然而，由于脑膜瘤即使经过初始治疗，仍可能复发或进展，因此需要新的治疗方法。在表达生长抑素的人类肿瘤中，已描述了合成长效生长抑素（SST）类似物的辅助治疗。目前尚不清楚猫脑膜瘤是否表达 SST 受体（SSTRs），且有关犬脑膜瘤的数据较少。我们假设 SSTR 在犬猫脑膜瘤中表达（S1）。
对 7 只犬和 11 只猫进行 SSTR 筛查，这些犬猫均患有经组织学证实的脑膜瘤。使用实时（RT）-qPCR 检测新鲜冷冻和福尔马林固定石蜡包埋（FFPE）样本中 SSTR1、SSTR2、SSTR3 和 SSTR5（犬）和 SSTR1-SSTR5（猫）的 RNA 表达。使用免疫组织化学（IHC）评估 FFPE 样本中 SSTR1 和 SSTR2 的表达。通过 Western blot 确认用于犬和猫物种的抗体的特异性。
在犬脑膜瘤（n=7）中，所有样本均检测到 SSTR1、SSTR2 和 SSTR5 的 RNA 表达；仅在 33%的样本中检测到 SSTR3 RNA 表达。在猫脑膜瘤（n=12）中，分别在 91%、46%、46%和 36%的样本中检测到 SSTR1、SSTR4、SSTR5 和 SSTR2 的 RNA 表达；未检测到 SSTR3。总体而言，FFPE 样本的检出率较低。IHC 显示两种物种的所有样本均表达 SSTR1 和 SSTR2。然而，由于存在弥漫性背景染色，在解释 IHC 结果时需要谨慎。
SSTRs 在犬猫脑膜瘤中广泛表达，这鼓励进一步研究 SSTR 表达，以开展关于辅助治疗长效 SST 类似物效果的试验。
