TRIM3通過調控PIAS1-STAT1軸抑制膠質瘤發生發展

【中圖分類號】 R739.41 【文獻標志碼】 A 【文章編號】1672-7770（2025）02-0149-10

Abstract： Objective To explore the role and molecular mechanisms TRIM3 in the occurrence and development human glioblastoma through PIAS1-STAT1. Methods Lentiviral overexpression TRIM3 and shRNA-transfected GBM cell lines U251 and U87 were constructed， with corresponding control groups CON335 and CON313. The FLAG-TRIM3 plasmid was used to transfect GBM cells and 293T cells， to construct overexpression cell lines. Living cell counting （CCK-8）， plate cloning experiments， Transwell chambers， and flow cytometry were used to analyze the proliferative activity， clumping， migration ability， and apoptosis glioma cells. Western blot and co-immunoprecipitation（Co-IP） experiments were conducted to detect the interaction between TRIM3 and PIAS1 proteins， as well as the specific molecular mechanisms. Real-time quantitative fluorescent polymerase chain reaction（ PCR） was used to detect the mRNA expression TRIM3 and PIASI. Dual-luciferase reporter gene assays were employed to test the impact TRIM3 on STAT1 activity. Nude mouse intracranial tumor models were used to demonstrate the impact TRIM3 on glioma formation in vivo. Results Compared to normal brain tissue cells， the expression TRIM3 was significantly reduced in GBM tissues. The expression level TRIM3 decreased with the WHO grades. Overexpression TRIM3 in glioma cells resulted in a significant attenuation their proliferative， clumping，and migratory capacities， and induced apoptosis in GBM cells. Western blot analysis revealed that overexpression TRIM3 in GBM cells was associated with a concentrationdependent reduction in PIASl protein levels. Real-time quantitative PCR data indicated that TRIM3 overexpression had no influence on the mRNA levels PIASl and STATl. Dual-luciferase reporter assays confirmed that TRIM3 enhances the transcriptional activity STATl. Moreover， TRIM3 mediated the degradation PIAS1 by promoting its poly-ubiquitination at the K48 residue， thus alleviating the suppressive effect PIAS1 on STATl transcription. In vivo studies using a nude mouse model demonstrated that， relative to the control group， the rate and size intracranial tumor formation were significantly reduced in mice with overexpressed TRIM3. ConclusionsTRIM3 disrupts the PIAS1-TRIM3 axis， suppressing glioma progression， and fers a novel therapeutic target.

Key words： gliobastoma； TRIM3 ； PIAS1 ； STAT1 ； ubiquitination

膠質母細胞瘤（glioblastoma，GBM）作為成人中樞神經系統中最常見的原發性惡性腫瘤，惡性程度極高。到目前為止，膠質瘤最常用的治療手段包括手術切除與放化療[2]；盡管有新的治療手段加入，例如腫瘤電場治療與貝伐珠單抗聯合再放療[3-4]，患者的5年總相對生存率仍然僅為 。同時需要注意的是，該病的復發率幾乎高達 100% ，預后極差[。因此，進一步探索膠質瘤發生發展的分子機制，發現可能的治療靶點對于改善其療效與預后具有重要的臨床意義。三結構域蛋白3（tripartitemotifcontaining3，TRIM3）是一種E3泛素連接酶，隸屬于TRIM家族，是一個含有環指結構域、一個或兩個鋅結合B-box結構域和卷曲-線圈結構域的三方基元[7]。近年來，TRIM3被證明在多種腫瘤中表現出抑癌作用，如肺癌、乳腺癌、胃癌等，可以通過鐵死亡、激素信號轉導等方法發揮作用[8-9]。但是，TRIM3在膠質瘤中發揮作用的具體機制尚不明確，亟待進一步研究。PIAS1蛋白是PIAS蛋白家族的一員，PIAS蛋白家族主要通過與多種轉錄因子和轉錄輔因子相互作用，調控下游基因的轉錄活性[，該家族其他成員還包括PIAS2（PIASx）、PIAS3和PIAS4（PIASy）[\"]。PIAS1最初被發現是作為 STAT1 的抑制劑，能夠通過SUMO化修飾調控 STAT1的活性，從而影響細胞的增殖、分化和凋亡[12]。有研究表明，STAT1在膠質瘤中能夠發揮抑癌作用[13]。在此之前，有相關報道稱TRIM59可以促進PIAS1和STAT1的結合，證明TRIM家族可能與PIAS1和STAT1存在互作關系[14]。同時，近年來PIAS1作為促癌因子在各類癌癥中發揮的作用也被越發重視，如肺癌、肝癌和黑色素瘤等[15-16]。然而，PIAS1 在GBM當中是否同樣發揮促癌作用，以及具體的作用機制仍不清楚。……