Immunohistochemical study on the nm23 gene produce (NDP kinase) in oral squamous cell carcinoma

NDPKA is not just a metastasis suppressor - be aware of its metastasis-promoting role in neuroblastoma

NDPK-A, encoded by nm23-H1 (also known as NME1) was the first metastasis suppressor discovered. Much of the attention has been focused on the metastasis-suppressing role of NDPK-A in human tumors, including breast carcinoma and melanoma. However, compelling evidence points to a metastasis-promoting role of NDPK-A in certain tumors such as neuroblastoma and lymphoma. To balance attention on this contrariety of NDPK-A in different cancer types, this review addresses the metastasis-promoting role of NDPK-A in neuroblastoma. Neuroblastoma is an embryonic tumor, arising from neural crest cells that fail to differentiate into the sympathetic nervous system. We summarize and discuss nm23-H1 genetics and the prognosis of neuroblastoma, structural and functional changes associated with the S120G mutation of NDPK-A, as well as the evidence supporting the role of NDPK-A as a metastasis promoter. Also discussed are the NDPK-A relevant molecular determinants of neuroblastoma metastasis, and metastasis-relevant neural crest development. Because of NDPK-A's dichotomous role in tumor metastasis as both a suppressor and a promoter, tumor genome/exome profiles are necessary to identify the molecular drivers of metastasis in the NDPK-A network for developing tumor-specific therapies.

Identification of tetranectin as a potential biomarker for metastatic oral cancer

Lymph node involvement is the most important predictor of survival rates in patients with oral squamous cell carcinoma (OSCC). A biomarker that can indicate lymph node metastasis would be valuable to classify patients with OSCC for optimal treatment. In this study, we have performed a serum proteomic analysis of OSCC using 2-D gel electrophoresis and liquid chromatography/tandem mass spectrometry. One of the down-regulated proteins in OSCC was identified as tetranectin, which is a protein encoded by the CLEC3B gene (C-type lectin domain family 3, member B). We further tested the protein level in serum and saliva from patients with lymph-node metastatic and primary OSCC. Tetranectin was found significantly under-expressed in both serum and saliva of metastatic OSCC compared to primary OSCC. Our results suggest that serum or saliva tetranectin may serve as a potential biomarker for metastatic OSCC. Other candidate serum biomarkers for OSCC included superoxide dismutase, ficolin 2, CD-5 antigen-like protein, RalA binding protein 1, plasma retinol-binding protein and transthyretin. Their clinical utility for OSCC detection remains to be further tested in cancer patients.

nm23 protein expression in metastatic and non-metastatic tongue squamous cell carcinoma

Oral squamous cells carcinoma (OSCC) shows unfavorable prognosis due to its invasion potential around the neighboring tissues and the elevated incidence of metastasis.

Aim

the present paper aims at analyzing the immunohistochemical expression of the nm23 protein in metastatic and non-metastatic SCCs of tongue.

Methods

the immuno-expression to the nm23-hl protein was diagnosed in 35 tongue SCC (15 of which exhibiting metastasis). Nm23-hl immuno-scores were assigned as follow: score 0 = absent, 1 = focal and 2 = diffuse expression.

Results

The Fisher's exact test was performed and there was no statistical difference between the nm23-hl immuno-scores and the tongue SCCs studied cases (p=0.365), although 66.7% of metastatic cases presented negative nm23-hl expression.

Conclusions

Protein nm23 was not associated with a positiveness for tongue SCC without metastasis. Thus, several others factors inherent to host and malignancy can be associated with the mechanisms that suppress the metastatic process in this disease.

Expressão da proteína nm23 em carcinoma de células escamosas de língua metastático e não-metastático

O carcinoma de células escamosas oral (CCEO) exibe prognóstico desfavorável em decorrência da capacidade de invasão aos tecidos vizinhos e elevada incidência de metástases. OBJETIVO: O presente trabalho objetiva analisar a expressão imunohistoquímica da proteína nm23 em CCEs de língua metastáticos e não-metastáticos. METODOLOGIA: A técnica da imunohistoquímica para a proteína nm23-h1 foi realizada em 35 casos de CCE de língua com metástase em 15 casos. Atribuiu-se escore 0, para ausência de marcação; 1, marcação focal e 2 para marcação difusa. RESULTADOS: Observou-se marcação focal para a proteína nm23 em 9 casos, difusa em 15, e ausência de marcação em 11 espécimes. O teste exato de Fischer foi aplicado, não havendo diferença estatisticamente significativa para positividade desta proteína nos casos metastáticos e não-metastáticos (p=0.365), apesar de que em 66.7% dos casos com metástase não houve marcação. CONCLUSÕES: A presença da proteína nm23 não esteve relacionada de forma positiva aos casos de CCE de língua sem metástase. Dessa forma, vários outros fatores inerentes à célula neoplásica e ao hospedeiro podem estar relacionados aos mecanismos supressores do processo metastático nesta entidade.

Nm23-H1 expression of metastatic tumors in the lymph nodes is a prognostic indicator of oral squamous cell carcinoma

We recently reported that low Nm23-H1 expression of primary oral squamous cell carcinoma (OSCC) was correlated with the occurrence of lymphatic metastasis. However, little is known about whether Nm23-H1 level of metastatic tumors in the cervical lymph nodes is reduced in comparison with primary oral cancers and its significance for patients' prognosis. By immunohistochemistry, we analyzed the Nm23-H1 expression in 52 pairs of OSCC specimens from primary oral cancers and their metastatic lymph nodes. Western blot analysis further confirmed the immunohistochemical interpretation. To verify the effects of Nm23-H1 on cell migration and invasion, we established several stable clones derived from a human OSCC cell line (SAS) by knockdown and overexpression. Wound-healing closure, transwell migration and invasion assays were performed to determine cell motility, migratory and invasive activities. Western blot analysis was carried out to evaluate cyclin A expression of OSCC cells with the altered Nm23-H1 levels following knockdown and overexpression. By immunohistochemistry, Nm23-H1 expression of metastatic lymph nodes was significantly lower than that of their primary oral cancers, supporting a role of Nm23-H1 in metastasis suppression. Negative Nm23-H1 interpretation of OSCC specimens, in either primary oral cancers or metastatic lymph nodes, indicated a poor survival outcome of patients. On the basis of in vitro studies of Nm23-H1 knockdown and overexpression, we demonstrated an inverse correlation between Nm23-H1 expression and the invasiveness of OSCC cells. Moreover, we observed the concomitant reduction in Nm23-H1 and cyclin A levels of metastatic tumors in both results of in vitro OSCC cells and ex vivo tumor specimens.

Molecular mediators of metastasis in head and neck squamous cell carcinoma

BACKGROUND

The presence of regional metastasis in patients with head and neck squamous cell carcinoma (HNSCC) is a common and adverse event associated with poor prognosis and high mortality. Although significant improvements in standard therapies have increased the efficacy of local tumor management, the high incidence of tumor recurrence has resulted in limited improvements in overall survival rates. Understanding the molecular mechanisms that mediate HNSCC invasion and metastasis may enable identification of novel therapeutic targets for the prevention and management of tumor dissemination.

METHODS

A literature review was performed.

RESULTS

Several biologic mediators and mechanisms that have been implicated in HNSCC metastasis, such as cell adhesion molecules, proteolytic enzymes, growth factor signaling, metastasis suppressor genes, and chemokine receptors were reviewed.

CONCLUSIONS

Prevention of HNSCC metastasis is an important clinical objective that requires an increased understanding of the molecular mechanisms of tumor invasion and dissemination.

Prognostic significance of nm23-H1 expression in oral squamous cell carcinoma

Recent studies indicated nm23-H1 played a role in cancer progression. Therefore, we investigated clinical significance of nm23-H1 expression in oral squamous cell carcinoma (OSCC). In total, 86 OSCC specimens were immunohistochemically stained with nm23-H1-specific monoclonal antibodies. Immunohistochemical staining of nm23-H1 was confirmed by immunoblotting. The relations between nm23-H1 expression and clinicopathologic variables were evaluated by chi(2) analysis. As increased size of primary tumour could escalate metastatic potential and the data of patients at the late T stage might confound statistical analyses, we thus paid special attention to 54 patients at the early T stage of OSCC. Statistical difference of survival was compared by a log-rank test. Immunohistochemically, nm23-H1 expression was detected in 48.8% (42 out of 86) of tumorous specimens. It positively correlated with larger primary tumour size (P=0.03) and inversely with cigarette-smoking habit (P=0.042). In patients at the early T stage, decreased nm23 expression was associated with increased incidence of lymph node metastasis (P=0.004) and indicated poor survival (P=0.014). Tumour nm23-H1 expression is a prognostic factor for predicting better survival in OSCC patients at the early T stage, which may reflect antimetastatic potential of nm23. Therefore, modulation of nm23-H1 expression in cancer cells can provide a novel possibility of improving therapeutic strategy at this stage. In addition, our results further indicated cigarette smoking could aggravate the extent of nm23-H1 expression and possibly disease progression of OSCC patients.

nm23-H1 suppresses invasion of oral squamous cell carcinoma-derived cell lines without modifying matrix metalloproteinase-2 and matrix metalloproteinase-9 expression

nm23-H1 is a candidate gene for the suppression of cancer metastasis. Several studies on human breast, hepatocellular, gastric, ovarian, and colon carcinomas and melanomas have shown that reduced nm23-H1 expression was closely related to metastatic progression with poor prognosis. However, the biochemical mechanism by which nm23-H1 suppresses the metastasis has yet to be elucidated. In this study, we analyzed the correlation between nm23 expression, cell motility, and the invasive abilities of six different oral squamous cell carcinoma cell lines (HSC2, HSC3, HSC4, KB, OSC19, and OSC20). Reduced mRNA/protein expression of the nm23-H1 was observed in three cell lines (HSC2, HSC3, and HSC4). These cell lines exhibited increased cell motility and an invasive character on organotypic raft culture. On the other hand, the cell lines (KB, OSC19, and OSC20) that showed a higher expression of nm23-H1 exhibited a threefold to fivefold reduced motility and also reflected fewer invasions compared to the former three cell lines. Because the HSC3 cells demonstrated the lowest nm23-H1 expression with the highest cell motility and invasive character, we established nm23-H1-transfected HSC3 cell lines to investigate whether exogenous nm23-H1 protein could inhibit cell migration and invasive activity. These transfectants showed a significant reduction in cell motility with exogenous nm23-H1 in a dose-dependent manner, and exhibited a noninvasive character. An immunofluorescence study demonstrated a distinct stress-fiber distribution at peripheral region of these transfectants. However, no significant difference of matrix metalloproteinase (MMP)-2 and MMP-9 expression was observed between mock transfectant and nm23-H1-transfected cells. These findings suggest that nm23-H1 inhibits the invasive activity of oral squamous cell carcinoma by suppression of cell motility without altering the MMP-2 and MMP-9 status.

Correlation of MTS1/p16 and nm23 mRNA expression with survival in patients with peripheral synovial sarcoma

BACKGROUND AND OBJECTIVES

Tumor suppressor gene MTS1/p16 (cyclin-dependent kinase-4 inhibitor) and a putative tumor metastasis suppressor gene nm23 (nucleoside diphosphate A kinase) have been identified in a variety of human tumors but have not been well studied in mesenchymal neoplasms.

METHODS

Expression of nm23 and MTS1 mRNA was determined by quantitative analysis from paraffin-embedded tumor tissue. The series comprised 31 patients with localized primary synovial sarcoma of soft tissues who were followed for a median of 83 months.

RESULTS

Neither MTS1 nor nm23 expression levels correlated with the patient's age or sex, tumor type, depth, size, mitotic rate, or extent of tumor necrosis. In addition, there was no correlation between MTS1 and nm23 levels. Patients' survival was not related to sex, age, tumor type, location, mitotic rate, or MTS1 mRNA level. The only factors that correlated with poor survival in multivariate analysis were the presence of extensive tumor necrosis (> 15%) and higher levels of nm23 mRNA.

CONCLUSIONS

Our results suggest that increased expression level of nm23 mRNA may be implicated in the mechanism of tumor progression and is associated with poor survival in patients with synovial sarcoma.