Yao Penglei, Ju Huanyu, Song Aohua, Wang Yue, Xin Guoshun, Wang Guangzhi, Ma Jian, Guo Mian
Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, China.
Department of Immunology, Harbin Medical University, Harbin, China.
Int Immunopharmacol. 2025 May 16;155:114629. doi: 10.1016/j.intimp.2025.114629. Epub 2025 Apr 15.
Glioblastoma (GBM) is the most malignant form of brain tumor, and GBM patients with poorer prognosis and highly immunosuppressive tumor microenvironment (TME) often exhibit PTEN deficiency in their tumor tissues. Therefore, new therapeutic strategies targeting immunosuppressive TME maybe useful in PTEN-deficient GBM.
Bioinformatics was used to assess gene expression, survival time and immunoinfiltration in PTEN-deficient GBM. CRISPR-Cas9 was used to construct gene knockout cell lines. C57BL/6 mouse orthotopic GBM models were used to conduct survival analysis and evaluate treatment effect of Ruxolitinib. Flow cytometry, immunohistochemistry, immunofluorescence and quantitative real-time PCR (qRT-PCR) to detect the polarization of macrophages. Immunoblotting, immunohistochemistry, qRT-PCR, enzyme linked immunosorbent assay, and dual-luciferase reporter assay were used to conduct mechanism research.
We identified that the elevated levels of phosphorylated STAT3 (p-STAT3) in PTEN-deficient GBM facilitate PDL1 transcription, which subsequently drives M2 polarization of macrophages. Furthermore, PTEN deficiency, along with high expression levels of STAT3 and PDL1, are associated with a shorter survival time in GBM patients. Notably, in orthotopic mouse models of GBM with PTEN deficiency, Ruxolitinib therapy reduces the levels of p-STAT3 and PDL1, inhibits the infiltration of M2 macrophages, and suppresses tumor growth.
The STAT3-PDL1 axis plays a crucial role in the M2 polarization of macrophages in PTEN-deficient GBM. The blockade of the STAT3-PDL1 axis by Ruxolitinib regulates the anti-tumor immune response and curtails tumor progression in PTEN-deficient GBM, highlighting its significant clinical implications.
胶质母细胞瘤（GBM）是最恶性的脑肿瘤形式，预后较差且肿瘤微环境（TME）具有高度免疫抑制性的GBM患者，其肿瘤组织中常出现PTEN缺陷。因此，针对免疫抑制性TME的新治疗策略可能对PTEN缺陷型GBM有用。
运用生物信息学评估PTEN缺陷型GBM中的基因表达、生存时间和免疫浸润情况。采用CRISPR-Cas9构建基因敲除细胞系。利用C57BL/6小鼠原位GBM模型进行生存分析并评估鲁索替尼的治疗效果。通过流式细胞术、免疫组织化学、免疫荧光和定量实时PCR（qRT-PCR）检测巨噬细胞的极化情况。运用免疫印迹、免疫组织化学、qRT-PCR、酶联免疫吸附测定和双荧光素酶报告基因测定进行机制研究。
我们发现PTEN缺陷型GBM中磷酸化STAT3（p-STAT3）水平升高促进了PDL1转录，进而驱动巨噬细胞的M2极化。此外，PTEN缺陷以及STAT3和PDL1的高表达水平与GBM患者较短的生存时间相关。值得注意的是，在PTEN缺陷的GBM原位小鼠模型中，鲁索替尼治疗可降低p-STAT3和PDL1水平，抑制M2巨噬细胞浸润，并抑制肿瘤生长。
STAT3-PDL1轴在PTEN缺陷型GBM中巨噬细胞的M2极化过程中起关键作用。鲁索替尼对STAT3-PDL1轴的阻断调节了抗肿瘤免疫反应并抑制了PTEN缺陷型GBM中的肿瘤进展，突显了其重要的临床意义。
