Lung cancer is one of the most common malignant neoplasms worldwide. CD24 is a marker of tumor stem cells that plays an important role in tumorigenesis. Hsp70 is an important molecular chaperone. However, the co-expression and interaction of CD24 and Hsp70, as well as the significance for the prognosis of lung cancer are still unclear. The expression levels of CD24 and Hsp70 were detected by immunohistochemistry and their correlation was analyzed. The expression levels of CD24 mRNA and protein were examined using qRT-PCR and western blotting in SPCA1, A549, H1975, and H1650 cell lines. A CD24-overexpressing cell model was established. The interaction between CD24 and Hsp70 was verified by co-immunoprecipitation and western blotting. CD24 and Hsp70 expression were significantly higher in lung cancer tissues than in adjacent tissues (CD24: P = 0.008; Hsp70: P < 0.001). CD24 protein expression showed a positive correlation with lymph node metastasis, TNM stage, and vascular cancer thrombus. Hsp70 protein expression showed a positive correlation with differentiation, lymph node metastasis, and TNM stage. CD24 and Hsp70 high expression were also correlated with poor survival. The positive co-expression rate of CD24 and Hsp70 in lung cancer tissues was 52.7% (49/93). CD24 and Hsp70 expression in lung cancer were positively correlated (r = 0.368, P < 0.001), and co-immunoprecipitation was verified that both endogenous and exogenous CD24 co-precipitated with Hsp70 directly or indirectly. When Hsp70 inhibitor 17-AAG was added to A549 cells, Hsp70 and CD24 protein expression were significantly decreased. The present study demonstrated that CD24 and Hsp70 were highly expressed in lung cancer tissues, and associated with invasion, metastasis, and poor survival. Hsp70 may regulate CD24 expression. Co-expression of CD24 and Hsp70 may be a prognostic biomarker for lung cancer.

中文翻译：

---

CD24 和 Hsp70 的共表达作为肺癌的预后生物标志物。

肺癌是世界范围内最常见的恶性肿瘤之一。CD24是肿瘤干细胞的标志物，在肿瘤发生中起重要作用。Hsp70是一种重要的分子伴侣。然而，CD24和Hsp70的共表达和相互作用，以及对肺癌预后的意义尚不清楚。免疫组化检测CD24和Hsp70的表达水平并分析其相关性。使用 qRT-PCR 和蛋白质印迹在 SPCA1、A549、H1975 和 H1650 细胞系中检查 CD24 mRNA 和蛋白质的表达水平。建立了CD24过表达细胞模型。CD24 和 Hsp70 之间的相互作用通过免疫共沉淀和蛋白质印迹验证。肺癌组织中 CD24 和 Hsp70 的表达显着高于癌旁组织（CD24：P = 0.008；Hsp70：P < 0.001）。CD24蛋白表达与淋巴结转移、TNM分期、血管癌栓呈正相关。Hsp70蛋白表达与分化、淋巴结转移和TNM分期呈正相关。CD24 和 Hsp70 的高表达也与较差的存活率相关。CD24和Hsp70在肺癌组织中的阳性共表达率为52.7%（49/93）。肺癌中CD24和Hsp70的表达呈正相关（r = 0.368，P < 0.001），免疫共沉淀证实内源性和外源性CD24均直接或间接与Hsp70共沉淀。当 Hsp70 抑制剂 17-AAG 添加到 A549 细胞中时，Hsp70 和 CD24 蛋白表达显着降低。本研究表明，CD24 和 Hsp70 在肺癌组织中高表达，与侵袭、转移和低生存率有关。Hsp70 可以调节 CD24 的表达。CD24 和 Hsp70 的共表达可能是肺癌的预后生物标志物。