Abstract:
Objective To preliminarily explore the relationship between tumor-associated macrophages (TAMs), M2 type TAMs and clinicopathological characteristics of papillary thyroid carcinoma (PTC).
Methods The study was based on data from patients enrolled in Yunnan Cancer Hospital from January 2010 to December 2017. Immunohistochemistry was used to detect the distribution of TAMs and M2 TAMs in the pathological tissues of 68 patients (51 cases of thyroid cancer, 42 cases of PTC, 9 cases of thyroid squamous cell carcinoma, and 17 cases of thyroid benign lesions) postoperatively. The distributions of TAMs and M2 TAMs in the tissues were detected by immumohistochemical staining, and the relationship between the results and clinicopathological characteristics were analyzed.
Results The distribution intensity of CD68+-, CD206+-, and CD68+/CD206+-labeled TAMs was higher in patients with thyroid cancer than in those with benign thyroid lesions (P<0.05). There were CD68-/CD206+-labeled TAMs in PTC tissues. Among 42 patients with PTC, the distribution intensity of CD68+- and CD68+/CD206+-labeled TAMs was higher in the group with lymph node metastasis and tumor size ≥2 cm than in the group without lymph node metastasis and tumor size <2 cm (P<0.05). In patients with PTC size <2 cm and stage Ⅰ or Ⅱ tumor, the distribution intensity of CD206+-labeled TAMs was higher than that of CD68+-labeled TAMs (P<0.05). The distribution intensity of CD206+-labeled TAMs in PTC tissues was positively correlated with the distribution intensity of CD68+-labeled TAMs (P<0.05). There was a statistically significant difference in the distribution of CD68+-labeled TAMs between the T3, TgAb, FT3, and FT4 normal and abnormal groups among patients with PTC (P<0.05). The distribution of CD68+/CD206+-labeled TAMs was statistically significant in the T3, FT3, and FT4 normal and abnormal groups of patients with PTC (P<0.05).
Conclusions 1) TAMs and M2 TAMs have a certain role in promoting the occurrence of thyroid cancer. TAMs can promote PTC neck lymph node metastasis, tumor growth and affect the regulation of thyroid hormone levels. 2) In the thyroid cancer microenvironment, M2 TAMs were not found to be subordinate to TAMs. 3) M2 TAMs mainly existed in the early microenvironment of PTC.