CD44与肿瘤关系的研究进展

CD44是具有高度异质性的细胞表面糖蛋白家族,CD44的过表达与肿瘤的浸润、转移、临床分期和耐药有关,是预后因子之一.可能作为肿瘤进展的标记物.另外,CD44还是多种肿瘤干细胞表面标记分子,在肿瘤复发、恶性生物学行为中可能发挥着重要作用,因此针对CD44的靶向治疗可能揭示了分子靶点治疗的新前景.     

NGF-induced TrkA/CD44 association is involved in tumor aggressiveness and resistance to lestaurtinib

There is accumulating evidence that TrkA and its ligand Nerve Growth Factor (NGF) are involved in cancer development. Staurosporine derivatives such as K252a and lestaurtinib have been developed to block TrkA kinase signaling, but no clinical trial has fully demonstrated their therapeutic efficacy. Therapeutic failures are likely due to the existence of intrinsic signaling pathways in cancer cells that impede or bypass the effects of TrkA tyrosine kinase inhibitors. To verify this hypothesis, we combined different approaches including mass spectrometry proteomics, co-immunoprecipitation and proximity ligation assays. We found that NGF treatment induced CD44 binding to TrkA at the plasma membrane and subsequent activation of the p115RhoGEF/RhoA/ROCK1 pathway to stimulate breast cancer cell invasion. The NGF-induced CD44 signaling was independent of TrkA kinase activity. Moreover, both TrkA tyrosine kinase inhibition with lestaurtinib and CD44 silencing with siRNA inhibited cell growth in vitro as well as tumor development in mouse xenograft model; combined treatment significantly enhanced the antineoplastic effects of either treatment alone. Altogether, our results demonstrate that NGF-induced tyrosine kinase independent TrkA signaling through CD44 was sufficient to maintain tumor aggressiveness. Our findings provide an alternative mechanism of cancer resistance to lestaurtinib and indicate that dual inhibition of CD44 and TrkA tyrosine kinase activity may represent a novel therapeutic strategy.     

CD133 expression in circulating tumor cells from breast cancer patients: Potential role in resistance to chemotherapy

CD133 has been associated with cell properties such as self renewal, migration and vasculogenic mimicry, potentially involved in generation of circulating tumor cells (CTCs). We characterized CD133 expression in CTCs of 98 nometastatic breast cancer (BC) patients. CTCs were isolated by immunomagnetic techniques using magnetic beads labeled with a multicytokeratin(CK)‐specific antibody (CK3‐11D5) and CTCs and CD133 detection through immunocytochemical methods. CK⁺/CD133⁺ CTCs were identified in 65% of patients at baseline and 47.8% after systemic therapy (p = 0.53). Correlation of CD133 status in CTCs with classical clinicopathological characteristics and response to therapy was performed. Her2 not amplified and low Ki‐67 index were positively correlated with presence of CK⁺/CD133⁺ CTCs. Before any treatment, CK⁺/CD133⁺ CTCs were more frequently isolated in patients with luminal BC subtype. No statistically significant differences were found between proportion of CK⁺/CD133⁺ CTCs and BC subtypes after systemic therapy, implying a relative enrichment of CK⁺/CD133⁺ CTCs in triple negative and HER2‐amplified tumors. While CK⁺/CTCs decreases after chemotherapy when analyzing the whole population, CK⁺/CD133⁺ CTCs were enriched in post‐treatment samples in nonluminal BC subtypes. These findings suggest the potential role of CD133 as a promising marker of chemoresistance in nonluminal BC patients. Further prospective studies and extensive preclinical modeling will be needed to confirm whether CD133 is a marker of resistance to chemotherapy, and its role as a target for novel anticancer therapies targeting cancer stem cells and tumor vasculature.     

食管癌细胞中粘附分子CD44表达及其临床意义

目的：探讨CD44粘附分子在食管癌细胞中的表达情况及其临床意义。方法：采用流式细胞术检测65例食管癌细胞和食管切缘粘膜细胞中的CD44表达率，进行临床病理分析和统计学比较。结果：食管癌细胞的CD44表达率明显高于食管切缘粘膜细胞（P＜0．001），中低分化食管癌细胞的CD44表达率高于高分化食管癌细胞（P＜0．05），伴有淋巴结转移的食管癌细胞CD44表达率高于无淋巴结转移的食管癌细胞（P＜0．05），Ⅲ-Ⅳ期食管癌细胞的CD44表达率高于Ⅱ期食管癌细胞（P＜0．05）。结论：检测食管癌细胞的CD44表达水平，可为临床提供判断食管癌患者临床分期和预后的参考指标。     

Serological Evaluation of Soluble CD44 in Renal Cancer

In this study, we examined the feasibility of using elevated serum CD44 concentration as an indicator in renal cancer. We performed enzyme-linked immunosorbent assays using 63 sera obtained from 47 patients with renal cancer and 16 healthy controls and evaluated the clinico-pathological parameters. The concentration of soluble CD44 standard (sCD44std), indicating the concentration of all circulating CD44 isoforms, was significantly higher in renal cancer patients than in normal individuals (745±170 ng/ml vs. 563±159 ng/ml, P =0.001). The concentration of soluble CD44 splice isoforms sharing exon v6 (sCD44v6) was also higher in the same patients (287±121 vs. 220±59, P =0.056). However, there were no correlations between the concentrations of sCD44std or sCD44v6 and clinico-pathological parameters such as grade, stage, histological type, tumor size and growth type. The ratio of sCD44std/sCD44v6 was higher in the rapid growth-type cancers than in the slow growth-type cancers (3.95±2.12 vs. 2.63±0.82, P =0.014). These findings suggested that the serum concentration of unknown soluble CD44 isoforms not sharing exon v6, which are present in sCD44std, increases in patients with rapid growth-type cancers. These findings indicated that sCD44std and sCD44v6 are not useful indicators of tumor burden and metastasis in patients with renal cancer, but that an unknown sCD44 isoform(s) plays a role in the biological behavior of the rapid growth-type cancers.     

CD44s和CD44v6在大肠腺癌中表达的临床意义

目的 :明确CD4 4s和CD4 4v6在大肠腺癌中表达的临床意义。方法 :应用免疫组织化学SP法检测 85例大肠癌和2 8例大肠腺瘤及 36例癌旁正常肠粘膜中CD4 4s和CD4 4v6蛋白的表达与分布。结果 :CD4 4s和CD4 4v6在大肠腺癌中表达率分别为6 7 1%和 92 9%,在伴有不典型增生的大肠腺瘤组织中分别为 6 6 7%和 88 9%,两者与癌旁正常肠粘膜组织相比 ,均有显著差异 (P <0 0 1)。CD4 4s和CD4 4v6蛋白阳性表达过度与大肠癌的临床Dukes 分期密切相关 (P <0 0 1)。但CD4 4s和CD4 4v6蛋白阳性表达均与大肠腺癌分化程度、有无淋巴转移及远处转移不相关 (P <0 0 1)。结论 :CD4 4s和CD4 4v6蛋白阳性表达对大肠癌早期诊断有一定意义 ,尤以CD4 4v6意义更大。而且 ,CD4 4v6是对大肠癌患者估计预后的一个较好指标。     

Clinical relevance of stem cell surface markers CD133, CD24, and CD44 in colorectal cancer

Colon cancer stem cells (CSC) identified by cell surface markers CD133, CD24, and CD44, have been shown to be involved with tumor formation, chemotherapy resistance, and the progression of metastatic disease. Using an in silico translational approach, we hypothesize that a combination of these CSC markers has prognostic value in a large cohort of patients with colorectal cancer. Clinicopathologic and RNA expression data from a total of 594 colorectal cancer (CRC) patients from TCGA were analyzed. The expression of CD133, CD24, and CD44 was individually defined as “high” or “low” based on the median expression. Disease specific survival (DSS) and overall survival (OS) were not associated with tumors that are CD133-high or CD44-high alone. Patients with CD24-high tumors have significantly better DSS (P<0.001) and OS (P = 0.043). CD24-high, CD44-high and CD133-high tumors were associated with significantly greater EGFR, KRAS and Ki67 expression (all P<0.001). CD133, CD24 and CD44-high tumors were independently enriched for conventional stemness-related signaling pathways such as Wnt/β-catenin and Hedgehog signaling pathways. There was no survival difference linked to CD133-high/CD44-low patients, but CD44-high/CD24-low patients have worse DSS (P = 0.005) compared with CD44-low/CD24-high patients. CD133-high/CD24-low tumors show significant negative enrichment of MYC targets, E2F targets, G2M checkpoint and mitotic spindle gene sets, suggesting less cell proliferation in these tumors. Patients with CD133-high/CD24-low tumors have worse DSS (P = 0.004) and OS (P = 0.044), and are more likely to have early and late recurrences. In conclusion, we demonstrated that CD133-high/CD24-low tumors may predict colorectal cancer prognosis.     

CD44V3和CD44V6在非小细胞肺癌组织中的表达及预后意义的研究

目的　为了探讨ＣＤ４４Ｖ３和ＣＤ４４Ｖ６ 在非小细胞肺癌组织中的表达及预后意义。方法应用免疫组织化学链菌素抗生物素蛋白过氧化物酶连接法（Ｓ－ Ｐ法）,对６２ 例有５ 年随访资料的非小细胞肺癌组织进行了ＣＤ４４Ｖ３ 和ＣＤ４４Ｖ６ 蛋白的检测。结果　非小细胞肺癌的ＣＤ４４Ｖ３ 和ＣＤ４４Ｖ６ 阳性表达率分别为６６．１％ 和６７．７％ ,皆与肿瘤病理分级及组织学类型无明显相关性;ＣＤ４４Ｖ３ 和ＣＤ４４Ｖ６阳性表达与非小细胞肺癌临床分期、淋巴结转移有显著相关性;非小细胞肺癌的ＣＤ４４Ｖ３ 和ＣＤ４４Ｖ６ 阳性表达在１ 年、３ 年术后生存率分别与５ 年比较有显著意义;结果还表明ＣＤ４４Ｖ３ 和ＣＤ４４Ｖ６ 阳性表达率与肿瘤大小有关,肿瘤直径＞ ３ｃｍ 者明显高于肿瘤直径≤３ｃｍ 者（Ｐ＜ ０．００５）。结论　在非小细胞肺癌中,ＣＤ４４Ｖ３ 和ＣＤ４４Ｖ６阳性表达提示容易发生淋巴结转移,多见于晚期肺癌,预后较差。ＣＤ４４Ｖ３和ＣＤ４４Ｖ６可作为临床评估非小细胞肺癌进展的辅助指标之一。     

靶向CD44的shRNA片段逆转人胰腺癌细胞株PANC-1侵袭表型机制

目的:利用RNA干扰技术沉默人胰腺癌细胞株PANC-1中CD44的表达,观察其对肿瘤侵袭性的抑制效果。方法:设计合成有效地干扰CD44的shRNA序列。结果:通过平板克隆形成实验、软琼脂集落形成试验、Transwell小室侵袭实验发现,胰腺癌细胞株转染干扰CD44的shRNA序列后,其相关的增殖以及侵袭能力明显受抑制。Western Blot发现随着CD44的下调,AKT被逐渐上调,而p-ERK、p-AKT却被逐渐下调。结论:靶向CD44的shRNA技术可有效降低人胰腺癌细胞株PANC-1的侵袭能力,可能的机制与影响其下游的p-AKT、p-ERK表达有关。针对CD44的RNA干扰具有潜在的临床价值。     

CD44~+/CD24~-、CD44~-/CD24~+在乳腺良恶性病变中的分布特点和临床病理意义

[目的]探讨CD44+/CD24-细胞、CD44-/CD24+细胞在乳腺癌发生不同阶段中(乳腺良性增生、乳腺不典型增生、乳腺原位癌、乳腺癌)分布规律,及其与乳腺癌临床病理因素之间的关系。[方法]采用免疫组化双染色方法检测45例正常乳腺组织、41例良性增生乳腺组织、39例不典型增生乳腺组织、51例乳腺原位癌组织、121例乳腺癌组织中CD44、CD24的表达情况,分析CD44+/CD24-细胞、CD44-/CD24+细胞在乳腺癌发生不同阶段中的数量和分布特点。[结果]CD44+/CD24-细胞存在于20.0%(9/45)的正常乳腺组织中,在29.3%(12/41)的乳腺良性增生组织、35.9%(14/39)的乳腺不典型增生组织、43.1%(22/51)的乳腺原位癌组织、52.9%(64/121)的浸润性乳腺癌组织中检测到CD44+/CD24-细胞,随着病变的进展,CD44+/CD24-细胞的数量也增加,差异具有显著统计学意义。此外,在33.3%(15/45)的正常乳腺组织中有CD44-/CD24+表达,43.9%(18/41)的乳腺良性增生组织、46.2%(18/39)的乳腺不典型增生组织、68.6%(35/51)的乳腺原位癌组织、86.0%(104/121)的浸润性乳腺癌组织检测到CD44-/CD24+细胞,且阳性细胞百分率随病变程度升高。在浸润性乳腺癌组织中CD44+/CD24-的表达与肿瘤有无淋巴结转移相关(P<0.05),但与病人年龄、月经状态、肿瘤的组织学类型、病理分级、肿瘤大小、ER、PR及Her-2的表达无显著相关(P>0.05),CD44-/CD24+的表达率与乳腺癌患者的各项临床病理特征均无统计学意义(P>0.05)。[结论]CD44+/CD24-、CD44-/CD24+细胞在乳腺增生和癌变过程中可能起重要作用。     

非小细胞肺癌CD44v6的表达及其在患者预后判定中的作用

背景与目的CD44v6的过度表达与人类多种恶性肿瘤的发生、发展和转移密切相关。本研究旨在观察CD44v6在非小细胞肺癌中的表达及其在患者预后判定中的作用。方法采用RTPCR和免疫组化法,对52例非小细胞肺癌患者手术标本进行CD44v6检测,并随访。结果免疫组化法和RTPCR法测得52例肺癌组织中CD44v6阳性表达率分别为69.2%和75.0%。低分化肺癌组织中CD44v6阳性表达率显著高于高分化和中分化肺癌(P<0.05),有淋巴结转移者显著高于无淋巴结转移者(P<0.01),Ⅲ期显著高于Ⅰ期和Ⅱ期(P<0.05)。CD44v6阴性表达者生存率显著高于CD44v6阳性表达者(P=0.0115)。多元logistic回归分析显示,CD44v6阳性表达(P=0.048)和pTNM分期(P=0.035)对生存率有显著影响。结论肺癌中存在CD44v6过度表达,检测CD44v6的表达有助于预测肺癌患者的预后。     

Deciphering the cellular source of tumor relapse identifies CD44 as a major therapeutic target in pancreatic adenocarcinoma

It has been commonly found that in patients presenting Pancreatic Ductal Adenocarcinoma (PDAC), after a period of satisfactory response to standard treatments, the tumor becomes non-responsive and patient death quickly follows. This phenomenon is mainly due to the rapid and uncontrolled development of the residual tumor. The origin and biological characteristics of residual tumor cells in PDAC still remain unclear. In this work, using PDACs from patients, preserved as xenografts in nude mice, we demonstrated that a residual PDAC tumor originated from a small number of CD44+ cells present in the tumor. During PDAC relapse, proliferating CD44+ cells decrease expression of ZEB1, while overexpressing the MUC1 protein, and gain morphological and biological characteristics of differentiation. Also, we report that CD44+ cells, in primary and residual PDAC tumors, are part of a heterogeneous population, which includes variable numbers of CD133+ and EpCAM+ cells. We confirmed the propagation of CD44+ cells in samples from cases of human relapse, following standard PDAC treatment. Finally, using systemic administration of anti-CD44 antibodies in vivo, we demonstrated that CD44 is an efficient therapeutic target for treating tumor relapse, but not primary PDAC tumors. We conclude that CD44+ cells generate the relapsing tumor and, as such, are themselves promising therapeutic targets for treating patients with recurrent PDAC.     

CD44 v6与非小细胞肺癌的研究进展

CD44是一种跨膜糖蛋白,是由单一基因所编码的具有高度特异性的单链膜表面糖蛋白家族。其主要参与细胞与细胞、细胞与基质之间的特异性黏附过程。 CD44v6是CD44家族的成员之一,其与非小细胞肺癌转移和预后的相关性成为近几年来研究的一大热点,本文就当前CD44 v6与非小细胞肺癌的研究进展做一综述。     

Ezrin、CD44在膀胱移行细胞癌的表达与意义

目的:探讨ezrin、CD44在膀胱移行细胞癌(BTCC)中的表达与意义。方法:采用免疫组织化学检测60例膀胱移行细胞癌与14例正常膀胱组织中ezrin、CD44的蛋白表达。结果:ezrin、CD44在膀胱移行细胞癌组织中的蛋白表达明显高于正常膀胱组织(P<0.05),ezrin、CD44的蛋白表达与膀胱移行细胞癌组织的病理分级、临床分期密切相关,ezrin、CD44蛋白表达的阳性表达随着膀胱肿瘤病理分级、临床分期的增高而增高(P<0.05)。ezrin、CD44的蛋白表达在膀胱移形细胞癌中有相关性。结论:ezrin、CD44在BTCC发生、发展过程中起重要作用。Ezrin、CD44在膀胱移形细胞癌的发生、进展中可能有协同性。ezrin可作为诊断、判断预后、指导治疗、随访检测的指标。     

CD44 increases the efficiency of distant metastasis of breast cancer

Metastasis is the predominant cause of death from cancer yet we have few biomarkers to predict patients at increased risk of metastasis and are unable to effectively treat disseminated disease. Analysis of 448 primary breast tumors determined that expression of the hylauronan receptor CD44 associated with high grade (p = 0.046), ER- (p = 0.001) and PR-negative tumors (p = 0.029), and correlated with increased distant recurrence and reduced disease-free survival in patients with lymph-node positive or large tumors. To determine its functional role in distant metastasis, CD44 was knocked-down in MDA-MB-231 cells using two independent shRNA sequences. Loss of CD44 attenuated tumor cell adhesion to endothelial cells and reduced cell invasion but did not affect proliferation in vitro. To verify the importance of CD44 to post-intravasation events, tumor formation was assessed by quantitative in vivo imaging and post-mortem tissue analysis following an intra-cardiac injection of transfected cells. CD44 knock-down increased survival and decreased overall tumor burden at multiple sites, including the skeleton in vivo. We conclude that elevated CD44 expression on tumour cells within the systemic circulation increases the efficiency of post-intravasation events and distant metastasis in vivo, consistent with its association with increased distant recurrence and reduced disease-free survival in patients.     

肺癌组织CD44、CD71的检测及与病理学的关系

目的了解肺癌组织CD44、CD71的表达与病理学的关系。方法应用流式细胞术对53例肺癌患者癌组织的CD44、CD71进行检测,并与其组织细胞学分类、分型,年龄,淋巴结转移等进行分析。结果CD44、CD71在低分化肿瘤细胞的表达明显高于中、高分化肿瘤细胞;肺肿瘤发生淋巴转移时,其CD44的表达明显增高,60岁以下患者CD71表达率明显高于60岁以上的患者。结论肺癌组织CD44的表达与肿瘤细胞的分化程度、淋巴结转移有关,CD71的表达与肿瘤细胞的分化程度、患者的年龄有关。     

Prognostic impact of the expression of putative cancer stem cell markers CD133, CD166, CD44s, EpCAM, and ALDH1 in colorectal cancer

Background:

The aim of this study was to elucidate the prognostic impact of putative cancer stem cell markers CD133, CD166, CD44s, EpCAM, and aldehyde dehydrogenase-1 (ALDH1) in colorectal cancer.

Methods:

A tissue microarray of 1420 primary colorectal cancers and 57 normal mucosa samples was immunostained for CD133, CD166, CD44s, EpCAM, and ALDH1 in addition to 101 corresponding whole tissue sections. Invasive potential of three colorectal cancer cell lines was tested.

Results:

Differences between normal tissue and cancer were observed for all markers (P<0.001). Loss of membranous CD166 and CD44s were linked to higher pT (P=0.002, P=0.014), pN (P=0.004, P=0.002), an infiltrating growth pattern (P<0.001, P=0.002), and worse survival (P=0.015, P=0.019) in univariate analysis only. Loss of membranous EpCAM expression was also linked to higher pN (P=0.023) and infiltrating growth pattern (P=0.005). The CD44s, CD166, and EpCAM expression were lost towards the invasive front. The CD44−/CD166− cells from three colorectal cancer cell lines exhibited significantly higher invasive potential in vitro than their positive counterparts.

Conclusions:

Loss, rather than overexpression, of membranous CD44s, CD166, and EpCAM is linked to tumour progression. This supports the notion that the membranous evaluation of these proteins assessed by immunohistochemistry may be representative of their cell adhesion rather than their intra-cellular functions.     

The adhesion molecule CD44v6 is associated with a high risk for local recurrence in adult soft tissue sarcomas

In many malignant diseases the expression levels of CD44 and its splice variant v6 (CD44v6) have been associated with the prognosis. The purpose of this study was to investigate the clinical significance of CD44 in adult soft tissue sarcomas (STS). 133 STS patients with a limb or superficial trunk tumour treated at the Helsinki University Central Hospital in 1987-1993 with a median follow-up time of 68 months were included in this study. The expression of CD44 and CD44v6 was determined immunohistochemically on paraffin-embedded tumour samples. 95% of the tumours expressed CD44 and CD44v6 was detected in 57%. Strong CD44 expression was associated with low grade (P = 0.04) and small tumour size (P = 0.02). In diploid tumours the CD44 expression was correlated with low S-phase fraction (P = 0.001). High expression of both, CD44 in general as well as that of CD44v6, predicted a higher risk for local recurrence (CD44: P = 0.01 and CD44v6: P = 0.05). Low CD44v6 content of the primary tumour correlated with poor survival (P = 0.02). Determining the expression of CD44 or CD44v6 in a primary STS could be a valuable tool for selecting the group of patients who might benefit from intensified local tumour treatment.     

脂多糖刺激前后树突状细胞CD44、CD24基因的表达

目的:检测脂多糖作用于树突状细胞前后CD44、CD24基因的表达情况。方法:从外周血分离单个核细胞,加入rhGM-CSF及rhIL-4,培养的第6天,实验组加入脂多糖刺激24 h而对照组不加,于刺激后不同时间点分别提取细胞总RNA,行real time PCR检测。结果:单个核细胞经GM-CSF及IL-4诱导6d后分化成为树突状细胞,表达较低水平的CD44及CD24。脂多糖刺激后树突状细胞的CD44及CD24表达均较对照组增高,CD44增高更明显。结论:树突状细胞受脂多糖刺激后CD44及CD24表达显著增高,这有利于DC-T细胞簇的形成及抗原的递呈,从而导致DC免疫功能的增强。