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.     

CD133与肿瘤干细胞研究进展

越来越多的证据表明肿瘤中存在肿瘤干细胞(cancer stem cells),并且其与肿瘤的增殖、转移、复发和对放化疗不敏感关系密切.因此,肿瘤治疗应当针对肿瘤干细胞,通过特异表面标记分选肿瘤干细胞是研究其生长特点的前提.近年来,CD133为研究最多的在于细胞(stem cell)和多种组织肿瘤干细胞表面独立表达的特异标记分子.通过CD133可以分选干细胞、前体细胞和肿瘤干细胞.众多研究表明,CD133~+肿瘤细胞与肿瘤的自我更新、分化潜能、信号传导调控、药物耐受、复发和预后等均有相关性.CD133~+细胞有望在干细胞相关疾病的治疗和肿瘤靶向治疗中发挥巨大作用.     

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.     

大肠癌细胞HCT-15肿瘤干细胞样细胞分离及成瘤性比较

目的:依据人大肠癌细胞HCT-15的表面标志物,分离其中的干细胞亚群。建立裸鼠体内原代大肠癌荷瘤模型,比较各亚群肿瘤体积和质量。方法:利用免疫磁珠分选技术,分离其中CD133/CD44干细胞亚群。分选得到CD133+CD44+、CD133+CD44-亚群分别接种于裸鼠体内,并观察肿瘤大小和质量。结果:CD133+CD44+和CD133+CD44-细胞亚群成功的从HCT-15细胞中分离出来。接种CD133+CD44+细胞的裸鼠形成的肿瘤体积［（2.76±0.22）cm3］和质量［（5.2±0.21）g］明显高于接种CD133+CD44-细胞裸鼠的肿瘤体积与质量［（1.56±0.34）cm3,（3.4±0.18）g］（P＜0.05）。结论:CD44阳性的大肠癌肿瘤干细胞成瘤能力明显高于CD44阴性的大肠癌肿瘤干细胞。     

CD133 expression is an independent prognostic marker for low survival in colorectal cancer

Colon cancer cells have previously been demonstrated to contain a subpopulation of CD133+ tumour cells that have the ability to initiate tumour growth and are thus referred to as colon cancer-initiating cells or colon cancer stem cells (CSCs). As CD133 is currently one of the best markers to characterise colon CSCs, we analysed CD133+ tumour cells in colorectal cancer specimens using immunohistochemistry. We show that CD133 detection is specific and that the CD133 antigen is localised on the glandular-luminal surface of colon cancer cells, whereas undifferentiated tumour cells at the front of invasion are CD133-. In addition, CD133+ cells are characterised in situ by lack of CK20 expression, whereas they are positive for EpCAM. Moreover, we show that CD133 expression in colorectal cancer is an independent prognostic marker that correlates with low survival in a stratified patient collective. Our results indicate that in colorectal cancer, the CD133+ tumour cells can be detected by immunohistochemistry, which facilitates their further characterisation in situ.     

RNA aptamers targeting cancer stem cell marker CD133

The monoclonal antibody against the AC133 epitope of CD133 has been widely used as a cell surface marker of cancer stem cells in several different cancer types. Here, we describe the isolation and characterisation of two RNA aptamers, including the smallest described 15 nucleotide RNA aptamer, which specifically recognise the AC133 epitope and the CD133 protein with high sensitivity. As well, both these aptamers show superior tumour penetration and retention when compared to the AC133 antibody in a 3-D tumour sphere model. These novel CD133 aptamers will aid future development of cancer stem cell targeted therapeutics and molecular imaging.     

肿瘤干细胞标志物CD133、CD44、OCT-4在小细胞肺癌中的表达及其临床意义

目的：探讨肿瘤干细胞标志物CD133、CD44、OCT-4与小细胞肺癌临床病理特征之间的相关性及临床意义。方法应用免疫荧光技术检测小细胞肺癌细胞株NCI-H82中肿瘤干细胞标志物CD133、CD44、OCT-4的表达;同时应用免疫组织化学法检测79例小细胞肺癌组织中CD133、CD44、OCT-4的表达。结果在小细胞肺癌细胞株NCI-H82中,CD133和CD 44的荧光信号为阳性表达,OCT-4的荧光信号为阴性表达。小细胞肺癌组织中CD133和CD44表达与肿瘤直径、淋巴结转移和临床分期相关,差异具有统计学意义（P＜0.05）。小细胞肺癌组织中OCT-4为阴性表达。结论 CD133和CD44可能是小细胞肺癌肿瘤干细胞的标志物,对小细胞肺癌的诊断和治疗有一定的临床意义。     

CD133/prominin-1与胃肠道肿瘤的研究进展

目的:探讨CD133/prominin-1在胃肠道肿瘤患者中的表达情况及其在肿瘤诊断治疗中的意义。方法:应用PubMed及CHKI期刊全文数据库检索系统,以胃癌、结肠癌、直肠癌、胃肠道肿瘤和CD133等为关键词,检索1989-01-2009-10的相关文献,共检索到英文文献1 071条,中文文献79条。纳入标准:1)CD133/prominin-1的基本资料介绍。2)CD133/prominin-1在正常胃肠道中的表达研究。3)CD133/promi-nin-1在胃肠道肿瘤患者体内表达、与临床病理和预后关系的研究。4)CD133/promi-nin-1与胃肠道肿瘤干细胞的关系及在肿瘤诊治中的应用研究。根据纳入的标准,精选了55篇文献,最后纳入了33篇文献进行分析综述。结果:CD133/prominin-1是一个含有5个跨膜区域的单链糖蛋白,主要在干细胞、祖细胞和肿瘤干细胞表达,一直被作为分离和鉴定这些细胞的标志。胃肠道中的正常组织和肿瘤组织中均有CD133的表达,胃肠道肿瘤中的CD133表达与肿瘤干细胞、临床病理和预后有关。结论:了解CD133在胃肠道肿瘤中的表达,可以加深我们对胃肠道肿瘤发生发展机制的认识,...     

Characterization of the conversion between CD133+ and CD133- cells in colon cancer SW620 cell line

The state of cancer stem cells (CSC) under reversible fluctuations, which has been revealed in breast cancer cells most recently, suggests that subpopulations with distinct phenotypes and functions within cancer cells can undergo inter-conversion. To investigate the possibility in colon cancer cells, we employed CD133 as the CSC marker, and characterized CD133 expression pattern and the biological features of the CD133⁺ and CD133^- subsets. Flow cytometry revealed that CD133 was bimodally expressed in SW620 cells among eight colon cancer cell lines. The CD133⁺ clonal SW620 cells displayed a differential gene expression profile, higher cellular reactive oxygen species (ROS), enhanced tumorigenesis and resistance to 5-fluorouracil. The conversion in term of the CD133 phenotype of the sorted cells was observed in vitro and in vivo. The fraction of the CD133⁺ cells decreased from 99% to 80% in the sorted CD133⁺ population while rising from 5 to 10% in the sorted CD133^- population during the first 20-day cultivation and then stayed almost unchanged. A fraction (about 20%) of the CD133⁺ clonal cells lost their CD133 marker while about 10% of the CD133^- clonal cells acquired the CD133 marker. 5-Azacytidine enhanced the fraction of the CD133⁺ cells in both of the CD133⁺ and CD133^- clonal cells. Our data demonstrate that CD133 expression is dynamic and reversible, and reveal the inter-conversion between the CD133⁺ and the CD133^- SW620 cells, suggesting that the CD133 phenotype of SW620 cell population is retained by the conversion between the two cell subsets.     

结直肠癌组织中CD133和Bmi-1的表达及临床意义

目的:探讨肿瘤干细胞标志物CD133和Bmi-1在结直肠癌组织中的表达,及其与临床病理因素的关系。方法:应用免疫组织化学方法检测60例手术切除的结直肠癌、癌旁和正常组织中CD133、Bmi-1的表达,对各指标之间的相关关系及其与性别、年龄、肿瘤的部位和大小、病理分级、侵袭深度、淋巴结转移、pTNM分期之间的关系进行分析。结果:结直肠癌组织中CD133、Bmi-1阳性表达率分别为50％（30/60）和73.33％（44/60）,显著高于癌旁及正常组织（P<0.01）;CD133的表达与淋巴结转移、pTNM分期和病理分级相关（P<0.05）,与其他临床病理参数均无关;Bmi-1的表达与淋巴结转移、pTNM分期相关（P<0.01）,与其他临床病理参数均无关;CD133和Bmi-1的表达呈正相关（P<0.05）。结论:结直肠癌组织中存在CD133+肿瘤细胞,即肿瘤干细胞;CD133+肿瘤细胞和Bmi-1表达在结直肠癌的发生、发展中起重要作用。肿瘤干细胞标志物CD133和Bmi-1表达可能成为判断肿瘤的恶性程度和预后的重要指标。     

结直肠癌组织ＣＤ１３３的表达及其意义

目的　探讨ＣＤ１３３在结直肠癌组织中的表达情况及与结直肠癌临床病理特征之间的关系。方法　收集经病理确诊且临床资料完整的结直肠癌５２例,同时选取切缘结肠组织５２例作为对照。应用免疫组化ＳＡＢＣ法检测结直肠癌和切缘结肠组织ＣＤ１３３的表达。结果　（１）结直肠癌组织ＣＤ１３３表达率显著高于切缘结肠组织,分别为７１％和９％（Ｐ＜０.０５）;（２）ＣＤ１３３表达与结直肠癌的病理分化程度、浸润深度和淋巴结转移相关（Ｐ＜０.０５）,但与肿瘤病理类型无显著相关性。结论　结直肠癌组织中存在ＣＤ１３３＋细胞,ＣＤ１３３表达与结直肠癌的分化程度、浸润深度及淋巴结转移有关,提示检测结直肠癌组织中ＣＤ１３３＋肿瘤干细胞的表达有助于评估肿瘤的恶性程度。     

5-Fluorouracil upregulates the activity of Wnt signaling pathway in CD133-positive colon cancer stem-like cells

Background and Objective:CD133-positive colon cancer stem like cells (CSLCs) are resistant to the conventional cytotoxic drug 5-fluorouracil (5-FU).Wnt signaling pathway plays important roles in colon cancer carcinogenesis and metastasis, and regulates the self-renewal capacity of CSLCs.In the present study, we explored the impact of 5-FU on Wnt signaling pathway of CD133-positive colon CSLCs, and the relation between Wnt signaling pathway and drug resistance of CD133-positive colon CSLCs.Methods:Magnetic a...     

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.     

CD133 negative glioma cells form tumors in nude rats and give rise to CD133 positive cells

CD133 is a cell surface marker expressed on progenitors of haematopoietic and endothelial cell lineages. Moreover, several studies have identified CD133 as a marker of brain tumor-initiating cells. In this study, human glioblastoma multiforme biopsies were engrafted intracerebrally into nude rats. The resulting tumors were serially passaged in vivo, and monitored by magnetic resonance imaging. CD133 expression was analyzed at various passages. Tumors initiated directly from the biopsies expressed little or no CD133, and showed no contrast enhancement suggesting an intact blood-brain barrier. During passaging, the tumors gradually displayed more contrast enhancement, increased angiogenesis and a shorter survival. Real-time qPCR and immunoblots showed that this was accompanied by increased CD133 expression. Primary biopsy spheroids and xenograft tumors were subsequently dissociated and flow sorted into CD133 negative and CD133 positive cell populations. Both populations incorporated BrdU in cell culture, and expressed the neural precursor marker nestin. Notably, CD133 negative cells derived from 6 different patients were tumorgenic when implanted into the rat brains. For 3 of these patients, analysis showed that the resulting tumors contained CD133 positive cells. In conclusion, we show that CD133 negative glioma cells are tumorgenic in nude rats, and that CD133 positive cells can be obtained from these tumors. Upon passaging of the tumors in vivo, CD133 expression is upregulated, coinciding with the onset of angiogenesis and a shorter survival. Thus, our findings do not suggest that CD133 expression is required for brain tumor initiation, but that it may be involved during brain tumor progression.     

CD133肿瘤干细胞标志物在肺癌中的应用进展

CD133作为肿瘤干细胞标志物已被广泛应用于临床,在肺癌干细胞的分选中亦具有重要作用。全文就肿瘤干细胞概念、CD133基因和结构、CD133与肿瘤干细胞的关系、CD133的临床应用以及CD133作为肿瘤干细胞标志物的局限性作一综述。     

CD133 is indicative for a resistance phenotype but does not represent a prognostic marker for survival of non‐small cell lung cancer patients

Despite advances in anticancer treatment, lung cancer still has poor prognosis. Recently, a cancer stem cell (CSC) hypothesis has emerged describing a small subset of tumor cells with stem cell properties. CSCs found in many solid tumors express CD133 antigen on the cell surface. The presence of CSC is correlated with poor survival of patients with glioblastomas, colon or prostate cancers. In this study, we evaluated whether CD133 expression in non‐small cell lung cancer (NSCLC) has a prognostic value in patients' survival. We also analyzed whether CD133 positivity of NSCLC correlates with the expression of resistance‐related proteins, angiogenic factors, oncogenes, proliferative activity or apoptosis. CD133 expression was retrospectively examined in a total of 88 cases of previously untreated NSCLC by immunohistochemistry. We found no correlation between CD133 positivity or the amount of CD133⁺ cells with NSCLC patients' survival, expression of oncogenes c‐myc, c‐N‐ras, c‐jun, c‐fos, c‐erbB1, c‐erbB2 or p53, angiogenic factors VEGF, VEGFR‐1, FGF, FGFR‐1, tissue factor and with proliferative activity or apoptosis in NSCLC tissues. However, there was a significant association between the expression of resistance‐related proteins glutathione S‐transferase, thymidylate synthase, catalase, O⁶‐methylguanine‐DNA methyltransferase and p170 and CD133. Because CD133 expression is linked to a resistant phenotype, detection of CD133⁺ cells may be useful to predict efficacy of cytotoxic therapy but CD133 is not a strong prognostic parameter for survival of patients with NSCLC.     

CD133和CD45在非小细胞肺癌组织中的表达及临床意义

目的 探讨CD133和CD45在非小细胞肺癌(NSCLC)组织中的表达及临床意义.方法 采用免疫组织化学SABC法检测65例NSCLC组织中CD133和CD45的表达,分析两者与肿瘤大小、组织学类型、TNM分期、组织分化程度及淋巴结转移之间的关系.结果 CD133和CD45在NSCLC组织中的阳性表达率分别为69.2％...