NCAM (neural cell adhesion molecules) expression in malignant mesotheliomas

Neural cell adhesion molecules (NCAM) are adhesion molecules expressed by neural and neuroendocrine tumors and a few biphasic tumors such as synovialosarcomas and breast phyllode tumors. To investigate NCAM expression in mesotheliomas, we studied 26 cases of epithelioid (n = 12), biphasic (n = 11), and sarcomatoid (n = 3) malignant mesotheliomas (MM), in comparison with normal mesothelium, and 50 primary non-small cell lung carcinomas (NSCLC) (25 adenocarcinomas [ADC] and 25 squamous cell carcinomas [SCC]), using electron microscopy as a gold standard for recognition of MM. NCAM reactivity using 123C3 antibody was compared with that of NE markers such as chromogranin A and synaptophysin. Although normal mesothelium remains negative, NCAM was expressed in 19 of 26 MM (73%) with a membranous staining on frozen or paraffin sections. In 6 of 12 epithelioid MM, the tumor cells expressed NCAM, whereas in 5 cases stromal fibroblasts showed a strong but focal staining. In 11 biphasic MM, 4 presented an NCAM reactivity of both epithelioid and spindle cell components, whereas in 7, only fusiform component was NCAM positive. Two of 3 sarcomatoid MM showed an NCAM expression. Chromogranin expression was never seen, whereas synaptophysin was noticed in 2 cases. No case of NSCLC showed membranous 123C3 staining, whereas 2 ADC weakly expressed synaptophysin. We conclude that NCAM expression in MM is reminiscent of its expression in mesoderm during fetal life and consistent with that reported in other biphasic tumors. These data show that NCAM expression occurs in 73% of MM, highly exceeding that observed in lung cancer.     

Neuroendocrine differentiation in non-small cell lung cancer and its relation to prognosis and therapy

AIMS: Histopathologists report the presence of neuroendocrine (NE) differentiation in non-small cell lung carcinoma (NSCLC) in up to a third of cases and are often questioned about its clinical relevance. The conclusions of previous studies have been inconsistent. This paper aims to provide an answer by examining a large series together with a comprehensive critique of the literature. METHODS AND RESULTS: Four hundred and thirty-nine cases of NSCLC were examined, immunohistochemically, using antibodies to chromogranin A (CGA), synaptophysin (SYN) and CD56/neural cell adhesion molecule (NCAM). Three hundred and forty-one cases had been treated with surgical resection and the remainder with chemotherapy. The results were compared with clinical outcome. Thity-six percent of cases had positive staining for at least one NE marker. CGA was positive in 5.5% of cases, SYN in 16.5% and NCAM in 28%. There was no association between the presence of NE markers and survival in either the surgically treated group or the chemotherapy-treated group. There was also no association between NE markers and response to chemotherapy in the latter group. CONCLUSIONS: The presence of immunohistochemically detected NE differentiation in NSCLC is not of prognostic significance.     

JLP5B9: new monoclonal antibody against polysialylated neural cell adhesion molecule is of value in phenotyping lung cancer

Non-small-cell lung cancer (NSCLC) is currently one of the most prevalent malignant tumors. It displays a wide variety of phenotypes which includes neuroendocrine markers commonly found on small-cell lung cancers (SCLC) such as the neural cell adhesion molecule (NCAM) and in particular its highly polysialylated isoform, embryonic NCAM (eNCAM). NSCLC with neuroendocrine differentiation may represent a subset of tumors whose cells have a more aggressive biological behavior. A tumor marker that distinguishes this latter sub-type could be of clinical relevance. Accordingly, we have raised a monoclonal antibody of the IgM type (JLP5B9) directed against capsular polysaccharides of N. meningitidis B which bears polysialic acid groups. We have demonstrated that JLP5B9 recognizes eNCAM with high affinity and that it is specifically directed against the polysialic acid moieties of NCAM. JLP5B9 was also found to react with human SCLC, NSCLC and neuroblastoma cell lines. We then used JLP5B9 as a specific probe for the detection of tissue eNCAM and found that it was expressed on up to 20% of tumor cells obtained from 5 out of 13 patients with NSCLC. This mAb deserves further investigation to evaluate its potential as a tool for serodiagnosis of lung cancer.     

非小细胞肺癌组织中MMP-9、TIMP-1表达及意义

目的 探讨非小细胞肺癌(non-small cell lung cancer,NSCLC)组织中基质金属蛋白酶9(MMP-9)、组织金属蛋白酶抑制剂-1(TIMP-1)的表达及其生物学行为的关系.方法 应用免疫组织化学SP法检测76例NSCLC和癌旁正常组织中MMP-9、TIMP-1的表达,并分析其表达与肺癌组织类型、肿瘤大小、TNM分期、分化程度、淋巴结转移的相关性.结果 MMP-9、TIMP-1在肺癌组织中的阳性表达率明显高于癌旁正常组织(P<0.05).NSCLC中MMP-9、TIMP-1表达与肿瘤的分化程度、临床分期、淋巴结转移有相关性(P<0.05),与肿瘤病理分型无关(P>0.05).结论 检测NSCLC中组织的MMP-9、TIMP-1的表达对判断肿瘤的恶性程度和预后评估有一定的意义.     

非小细胞肺癌中Naked1的表达及意义

目的探讨Naked1(NKD1)蛋白在非小细胞肺癌(non-small cell lung cancer,NSCLC)组织中的表达与预后的关系。方法采用RT-PCR、Western blot法对35例新鲜肺癌组织进行检测;采用免疫组化SP法对100例NSCLC石蜡标本进行检测。结果在79%的新鲜肺癌标本中,NKD1的蛋白水平明显低于相对应的癌旁正常肺组织,而mRNA水平明显高于正常肺组织(P<0.01)。在78%的NSCLC免疫组化标本中,NKD1的表达明显低于正常肺组织(P<0.01)。在肺鳞癌中NKD1的表达低于腺癌,并与分化程度呈正相关(P<0.01),与淋巴结转移(P<0.05)和TNM分期(P<0.01)呈负相关,NKD1低表达者的术后生存时间明显低于正常表达者(P=0.01)。结论在NSCLC中,NKD1 mRNA上调,而蛋白水平下调,其蛋白的下调程度与临床病理因素和不良预后相关。     

Aldehyde dehydrogenase 1 expression in cancer cells could have prognostic value for patients with non‐small cell lung cancer who are treated with neoadjuvant therapy: Identification of prognostic microenvironmental factors after chemoradiation

Prognostic factors for patients with non‐small cell lung cancer (NSCLC) who have been treated with neoadjuvant therapy have not been fully assessed. The purpose of this study was to analyze prognostic biomarkers in NSCLC after treatment with neoadjuvant therapy, with special reference to the immunophenotypes of both the cancer cells and stromal cells. A total of 52 patients with NSCLC who were treated with neoadjuvant therapy followed by complete resection were included. We examined the expressions of nine markers in the cancer cells and stromal cells. The 5‐year disease‐free survival rate of patients with high aldehyde dehydrogenase 1 (ALDH1) expression levels in their cancer cells was significantly lower than those with a low ALDH1 level (47.3% vs. 21.5%, respectively; P = 0.023). The other molecules expressed in cancer cells did not exhibit any prognostic value. In NSCLC without neoadjuvant therapy (case control, n = 104), expression of ALDH1 in cancer cells was not correlated with prognosis (P = 0.507). A multivariate analysis identified ALDH1 expression in cancer cells as significantly independent prognostic factors for disease‐free survival (P = 0.045). The current study indicated that the immunophenotypes of ALDH1 in cancer cells could have prognostic value for patients with NSCLC who are treated with neoadjuvant therapy.     

非小细胞肺癌中NDRG1与HIF-1α表达模式及相关性的研究

目的探讨非小细胞肺癌组织中NDRG1(N-myc下游调节因子1)与HIF-1α(缺氧诱导因子1α)的表达模式及关联。方法应用免疫组织化学方法检测105例非小细胞肺癌及癌旁肺组织中NDRG1和HIF-1α的蛋白表达。应用Western Blotting检测12对新鲜肺癌组织及癌旁肺组织中NDRG1及HIF-1α的蛋白表达。结果 NDRG1与HIF-1α在非小细胞肺癌组织中具有相似的表达模式,均主要表达于细胞浆,阳性率分别为55.2%(58/105)及50.5%(53/105),部分病例伴有细胞核(分别为20.0%(21/105)及35.2%(37/105))和细胞膜(分别为11.4%(12/105)及7.6%(8/105))的表达,总的阳性率分别为60.0%(63/105)及53.3%(56/105)。NDRG1在癌旁肺组织中的表达(17.1%(18/105))低于癌组织(<0.05),HIF-1α在癌旁肺组织中的表达(46.7%(49/105))与癌组织中的表达无显著差异(>0.05),NDRG1与HIF-1α在非小细胞肺癌组织中的表达水平呈正相关(r=0.210,<0.05)。Western Blotting结果显示NDRG1在肺癌组织中的表达高于癌旁肺组织(<0.05),其在癌组织中的表达与HIF-1α的蛋白表达呈正相关(<0.05)。HIF-1α在癌及癌旁组织中的表达无明显差异(<0.05)。结论 NDRG1在非小细胞肺癌高表达与HIF-1α表达呈正相关,二者可能在肿瘤内部缺氧诱导的应激反应过程中存在相互作用。     

Oncogenic role of the E3 ubiquitin ligase NEDD4-1, a PTEN negative regulator, in non-small-cell lung carcinomas

Loss of the PTEN tumor suppressor gene occurs frequently in non-small-cell lung carcinoma (NSCLC), although neither genetic alterations nor epigenetic silencing are significant predictors of PTEN protein levels. Since recent reports implicated neural precursor cell expressed, developmentally down-regulated 4-1 (NEDD4-1) as the E3 ubiquitin ligase that regulates PTEN stability, we investigated the role of NEDD4-1 in the regulation of PTEN expression in cases of NSCLC. Our findings indicate that NEDD4-1 plays a critical role in the development of NSCLC and provides novel insight on the mechanisms that contribute to inactivate PTEN in lung cancer. Immunohistochemical analysis on tissue microarrays containing 103 NSCLC resections revealed NEDD4-1 overexpression in 80% of tumors, which correlated with the loss of PTEN protein (n=98; P<0.001). Accordingly, adoptive NEDD4-1 expression in NSCLC cells decreased PTEN protein stability, whereas knock-down of NEDD4-1 expression decreased PTEN ubiquitylation and increased PTEN protein levels. In 25% of cases, NEDD4-1 overexpression was due to gene amplification at 15q21. In addition, manipulation of NEDD4-1 expression in different lung cell systems demonstrated that suppression of NEDD4-1 expression significantly reduced proliferation of NSCLC cells in vitro and tumor growth in vivo, whereas NEDD4-1 overexpression facilitated anchorage-dependent and independent growth in vitro of nontransformed lung epithelial cells that lack pRB and TP53 (BEAS-2B). NEDD4-1 overexpression also augmented the tumorigenicity of lung cancer cells that have an intact PTEN gene (NCI-H460 cells).     

Polysialic acid of the neural cell adhesion molecule distinguishes small cell lung carcinoma from carcinoids.

The neural cell adhesion molecule (NCAM) exists in various types of neuroendocrine cells and their tumors. A typical feature of NCAM is polysialic acid, of which the chain length is developmentally regulated. The authors have performed a comparative immunohistochemical study on small cell lung carcinomas and bronchial as well as gastrointestinal carcinoids with the monoclonal antibody (MAb) 735 reactive with the long-chain form of polysialic acid. The small cell lung carcinomas, irrespective of their histological type, were positive for polysialic acid. Metastatic tumor cell complexes also exhibited immunostaining. The tumor cell-surface-associated immunostaining for polysialic acid was sensitive to endoneuraminidase. The mature and atypical bronchial and gastrointestinal carcinoids were not immunoreactive for polysialic acid. Cytoplasmic staining in groups of cells of carcinoids (2 of 28 cases) was due to nonspecific antibody binding, which could be prevented by increased ion strength. These data indicate that neuroendocrine tumors of the lung can be distinguished by their content of highly sialylated NCAM.     

Cardiac troponin I is abnormally expressed in non-small cell lung cancer tissues and human cancer cells

Cardiac troponin I (cTnI) is the only sarcomeric protein identified to date that is expressed exclusively in cardiac muscle. Its expression in cancer tissues has not been reported. Herein, we examined cTnI expression in non-small cell lung cancer (NSCLC) tissues, human adenocarcinoma cells SPCA-1 (lung) and BGC 823 (gastric) by immunohistochemistry, western blot analysis and real-time PCR. Immunopositivity for cTnI was demonstrated in 69.4% (34/49) NSCLC tissues evaluated, and was strong intensity in 35.3% (6/17) lung squamous cell carcinoma cases. The non-cancer-bearing lung tissues except tuberculosis (9/9, 100%) showed negative staining for cTnI. Seven monoclonal antibodies (mAbs) against human cTnI were applied in immunofluorescence. The result showed that the staining pattern within SPCA-1 and BGC 823 was dependent on the epitope of the cTnI mAbs. The membrane and nucleus of cancer cells were stained by mAbs against N-terminal peptides of cTnI, and cytoplasm was stained by mAbs against the middle and C-terminal peptides of cTnI. A ~25 kD band was identified by anti-cTnI mAb in SPCA-1 and BGC 823 extracts by western blot, as well as in cardiomyocyte extracts. The cTnI mRNA expressions in SPCA-1 and BGC 823 cells were about ten thousand times less than that in cardiomyocytes. Our study shows for the first time that cTnI protein and mRNA were abnormally expressed in NSCLC tissues, SPCA-1 and BGC 823 cells. These findings challenge the conventional view of cTnI as a cardiac-specific protein, enabling the potential use of cTnI as a diagnostic marker or targeted therapy for cancer.     

microRNA-377 inhibits non-small-cell lung cancer through targeting AEG-1

Non-small-cell lung cancer (NSCLC) is the leading cause of cancer-related deaths. MicroRNAs (miRNAs) have been reported to be involved in tumorigenesis. However, the underlying mechanisms of microRNA-377 (miR-377) in NSCLC remain unknown. Hence, in the present study, we aimed to explore the role of miR-377 in the development of NSCLC, with identifying its target genes. The results showed that miR-377 expression was significantly decreased in NSCLC tissues as well as in NSCLC cell lines. Moreover, high expression of miR-377 could markedly inhibit the viability, proliferation, migration and invasion of NSCLC cells. The bioinformatics analysis results showed that astrocyte elevated gene-1 (AEG-1), an oncogene as previously reported, was a potential target gene of miR-377, which was further validated by dual-luciferase reporter assay. Besides, the expression of AEG-1 in protein level was decreased by miR-377 overexpression, but not in mRNA level. In addition, AEG-1 overexpression could reverse the inhibitory effects on NSCLC cells caused by miR-377 transfection. In conclusion, our results suggested that miR-377 played an important role in the development of NSCLC by regulating AEG-1 and may be a potential therapeutic target for NSCLC.