Lv Zhuo, Xu Li-Yan, Shen Zhong-Ying, Zhang Fa-Ren, Xu Xiu-E, Li En-Min
Department of Biochemistry and Molecular Biology, Medical College of Shantou University, Shantou 515041, P.R. China.
Oncol Lett. 2010 Jan;1(1):103-108. doi: 10.3892/ol_00000019. Epub 2010 Jan 1.
Neutrophil gelatinase-associated lipocalin (NGAL), a member of the lipocalin family, is related to imflammation and tumour. Recently, a specific cell-surface receptor (24p3R/NGALR) for lipocalin 24p3 was reported. However, the characteristics of NGALR expression in colorectal carcinoma (CRC) are not known. The objectives of this study were to investigate the expression of NGAL and NGALR in CRC specimens, and determine any relationship between the expression of these proteins and tumour progression. In the present study, CRC specimens of 102 patients were obtained, and the expression of NGAL, NGALR, ferritin and Ki67 was analyzed in paraffin sections by immunohistochemistry. Statistical analyses of the data collected were performed with SPSS software. We found that the cytoplasmic staining of NGAL, NGALR and ferritin, as well as the nuclear staining of Ki67 were significantly up-regulated in CRC tissues compared with normal colorectal tissues. Expression of NGAL was related to the deeper invasion of CRC (P=0.026), while NGALR was significantly associated with a deeper invasion (P=0.018) and a high degree of Tumor, Node and Metastasis stages (P=0.042) in CRC. The NGAL/NGALR co-expression was associated with poor cellular differentiation (P=0.004). Positive correlations between NGAL and NGALR (r=0.432, P<0.01), NGAL and ferritin (r=0.374, P<0.001), NGALR and Ki67 (r=0.228, P<0.05), NGAL/NGALR co-expression and ferritin (r=0.349, P<0.001), as well as NGAL/NGALR co-expression and Ki67 (r=0.205, P<0.05) were observed. However, the expression of NGAL or NGALR was not significantly associated with patient survival. These findings detected an elevated expression of NGAL and NGALR resulting in poor cellular differentiation and a deeper invasion of CRC. Thus, NGALR may be a novel target for the treatment of CRC.
中性粒细胞明胶酶相关脂质运载蛋白（NGAL）是脂质运载蛋白家族的一员，与炎症和肿瘤相关。最近，有报道称存在一种针对脂质运载蛋白24p3的特异性细胞表面受体（24p3R/NGALR）。然而，结直肠癌（CRC）中NGALR表达的特征尚不清楚。本研究的目的是调查NGAL和NGALR在CRC标本中的表达情况，并确定这些蛋白的表达与肿瘤进展之间的关系。在本研究中，获取了102例患者的CRC标本，并通过免疫组织化学分析石蜡切片中NGAL、NGALR、铁蛋白和Ki67的表达。使用SPSS软件对收集的数据进行统计分析。我们发现，与正常结直肠组织相比，CRC组织中NGAL、NGALR和铁蛋白的细胞质染色以及Ki67的核染色均显著上调。NGAL的表达与CRC的浸润深度相关（P = 0.026），而NGALR与CRC的浸润深度增加（P = 0.018）和高肿瘤、淋巴结转移分期（P = 0.042）显著相关。NGAL/NGALR共表达与细胞分化差相关（P = 0.004）。观察到NGAL与NGALR之间呈正相关（r = 0.432，P < 0.01），NGAL与铁蛋白之间呈正相关（r = 0.374，P < 0.001），NGALR与Ki67之间呈正相关（r = 0.228，P < 0.05），NGAL/NGALR共表达与铁蛋白之间呈正相关（r = 0.349，P < 0.001），以及NGAL/NGALR共表达与Ki67之间呈正相关（r = 0.205，P < 0.05）。然而，NGAL或NGALR的表达与患者生存率无显著相关性。这些发现检测到NGAL和NGALR的表达升高导致细胞分化差和CRC浸润加深。因此，NGALR可能是CRC治疗的一个新靶点。
