Department of Radiotherapy, The First Affiliated Hospital of Anhui Medical University, 230022 Hefei, Anhui, China.
The Center for Scientific Research, The First Affiliated Hospital of Anhui Medical University, 230022 Hefei, Anhui, China.
Front Biosci (Landmark Ed). 2022 Aug 10;27(8):238. doi: 10.31083/j.fbl2708238.
To investigate the synergic effect and underlying mechanism of Endostar, a recombinant human endostatin used for anti-angiogenesis, in radiotherapy for cervical cancer.
The Cell Counting Kit-8 (CCK-8) assay and plate cloning experiment were first employed to analyze the proliferation of HeLa and SiHa cervical cancer cells and human umbilical vein vascular endothelial cells (HUVECs). Flow cytometry was used to detect apoptosis and cell cycle progression. A tube formation assay was used to assess angiogenesis . The expression of gamma H2A histone family member X (γ-H2AX) and activation of the vascular endothelial growth factor receptor (VEGFR) signaling pathway were detected by immunofluorescence and western blotting, respectively. In a HeLa xenograft model, tumor tissue expression of CD31 and alpha smooth muscle actin and serum expression of VEGF-A were detected by immunohistochemistry (IHC) and enzyme-linked immunosorbent assay, respectively.
The CCK-8 and plate cloning assays showed that Endostar and radiotherapy synergistically inhibited the growth of HUVECs but not HeLa and SiHa cells. The flow cytometric results showed that Endostar only promoted radiotherapy-induced apoptosis and G2/M phase arrest in HUVECs ( < 0.05). Endostar combined with radiotherapy also significantly inhibited tube formation by HUVECs ( < 0.05). Furthermore, Endostar inhibited the radiotherapy-induced expression of γH2AX ( < 0.05) and phosphorylation of VEGFR2/PI3K/AKT/DNA-PK in HUVECs ( < 0.05). IHC showed that Endostar enhanced the inhibitory effect of radiotherapy on the microvessel density in xenograft tumor tissues ( < 0.05), as well as serum VEGF-A expression ( < 0.05). The tumor volume in the combination therapy groups (1200 mm) was significantly lower than in the control group (2500 mm; < 0.05).
Our findings provide experimental evidence and a theoretical basis for the application of Endostar in combination with irradiation for anti-cervical cancer treatment.
研究重组人血管内皮抑制素恩度（一种抗血管生成药物）联合放疗对宫颈癌的协同作用及其作用机制。
采用细胞计数试剂盒（CCK-8）检测和平板克隆实验分析宫颈癌细胞（HeLa 和 SiHa 细胞）和人脐静脉血管内皮细胞（HUVEC）的增殖情况，流式细胞术检测细胞凋亡和细胞周期进程，小管形成实验检测血管生成能力，免疫荧光法和 Western blot 法检测 γH2A 组蛋白家族成员 X（γ-H2AX）的表达和血管内皮生长因子受体（VEGFR）信号通路的激活情况。在 HeLa 移植瘤模型中，采用免疫组化（IHC）和酶联免疫吸附试验（ELISA）检测肿瘤组织 CD31 和α平滑肌肌动蛋白的表达以及血清血管内皮生长因子 A（VEGF-A）的表达。
CCK-8 和平板克隆实验结果显示，恩度与放疗协同抑制 HUVEC 的生长，而对 HeLa 和 SiHa 细胞无协同抑制作用。流式细胞术结果显示，恩度仅促进放疗诱导的 HUVEC 凋亡和 G2/M 期阻滞（<0.05）。恩度联合放疗还显著抑制 HUVEC 的小管形成（<0.05）。此外，恩度抑制放疗诱导的 HUVEC 中 γH2AX 的表达（<0.05）和 VEGFR2/PI3K/AKT/DNA-PK 的磷酸化（<0.05）。IHC 结果显示，恩度增强了放疗对移植瘤组织微血管密度的抑制作用（<0.05），以及血清 VEGF-A 的表达（<0.05）。联合治疗组（1200mm）的肿瘤体积明显低于对照组（2500mm；<0.05）。
本研究结果为恩度联合放疗治疗宫颈癌提供了实验依据和理论基础。
