Expression of nm23-H1 gene product in nasopharyngeal carcinoma and its clinical significance

Objective: The nm23 gene is one of the tumor metastatic suppressor genes. The expression of nm23-H1 has been reported to be inversely associated with metastatic potentiality in a number of human carcinomas, including breast, colorectal, gastric, hepatocellular and gallbladder carcinomas. In this study, the immunohisto-chemical staining of nm23-H1 protein in human naso-pharyngeal carcinoma (NPC) was examined, and the relationship between nm23-H1 and both metastasis and prognosis of patients with NPC was also investigated. Methods: Routine LSAB immunohistochemistry with the nm23-H1 monoclonal murine antibody was employed to study the expression of nm23-H1 protein in 95 paraffin-embedded specimens of NPC treated at our hospital. The clinical pathologic data and results of follow-up were also retrieved. Comparisons between patients with and without expression of nm23-H1 protein with respect to metastasis, loco-regional recurrence and survival were performed using Log rank test. Multivariate prognostic analyses were performed by using Cox’s regression model. Results: Nm23-H1 negative expressive tumors were associated with a higher incidence of lymph-node metastasis (86.7%) than those of nm23-H1 positive (48.6%,P<0.01). Nm23-Hl negative expressive tumors were associated with a high incidence of recurrence and distant metastasis after radiotherapy (P<0.05). A significant association was found between expression of nm23-H1 and prognosis (P<0.01). The expression of nm23-H1 indicated favorable prognosis. Conclusion: It was suggested that nm23-H1 negative expression was significantly associated with lymph-node metastasis, recurrence and distant metastasis. Nm23-H1 may have value for predicting the prognosis of NPC.     

膀胱癌中nm23-H1基因突变及表达的意义

目的：探讨ｎｍ２３－Ｈ１基因在膀胱癌中突变及表达的意义。方法：应用半定量逆转录聚合酶链反应（ＲＴ－ＰＣＲ）和银染单链构象多态性（ＳＳＣＰ）方法检测ｎｍ２３－Ｈ１基因在２５例膀胱癌组织及１５例对照组织中突变和表达情况。结果：对照粘膜中未检测出ｎｍ２３－Ｈ１基因突变,而在２５例膀胱癌组织中发现６例出现ＰＣＲ产物单链泳动状态异常,异常率为２４％。癌组织和对照组织均有ｎｍ２３－Ｈ１基因ｍＲＮＡ的表达,８８     

nm23-H1基因表达与卵巢癌转移的相关性

背景与目的：转移是卵巢癌治疗失败及患者死亡的首要原因。然而,目前对卵巢癌转移潜能的分子机制知之不多。本研究旨在筛选高频转移卵巢恶性肿瘤细胞,分析卵巢癌高频转移细胞模型中nm23．H1基因表达与肿瘤转移特性的相关性,为系统实验研究和临床实践提供依据。方法：通过反复动物接种和体外培养,观察动物肺转移状况,筛选高频转移细胞株,比较原发肿瘤和转移肿瘤的特征,并应用Northem blot和Westem blot方法测定各类肿瘤细胞nm23 mRNA和蛋白表达水平。结果：8株卵巢恶性肿瘤细胞中,4株有较高转移潜能,多次培养接种可筛选出高频转移细胞亚群。各类细胞nm23mRNA和蛋白表达水平与肿瘤转移特性呈负相关(r=0．96,P=0．0001)。结论：由基因分子水平决定的肿瘤转移趋势在不同肿瘤种类及细胞亚群中有明显差异;卵巢癌中nm23 mRNA和蛋白的表达与其转移能力的降低有密切关系,可作为判定卵巢癌预后的敏感指标。     

p53和nm23-H1蛋白表达与食管癌浸润转移的关系

Objective To study the relationship between expression of p53 and nm23-H1 and differentiation, invasiveness and metastasis in human esophageal carcinoma, and the correlation between expression of p53 and nm23-H1. Methods Expression of p53 and nm23-H1 in 50 patients with squamous cell carcinoma of esophagus was detected by using immuno-histochemical S-P methods. Results 35 cases (70%) and 32 cases (64%) of esophageal squamous cell carcinoma were positive for nm23-H1 protein and p53 protein, respectively. The expression of nm23-H1 was related to lymphatic metastasis (P<0.025), but not related to tumor differentiation, invasiveness, tumor location, tumor length, patient's gender and age (P>0.05). The lymphatic metastasis location positive group had a very lower expression of nm23-H1 and the negative rate was 70.8%, but the negative group had a higher expression and the positive rate was 65.4%. The expression of p53 was related to tumor differentiation and invasiveness (P<0.05), but not related to lymphatic metastasis, tumor location, tumor length, patient's gender and age(P>0.05). Among the three groups, the high differentiation group had the lowest expression of p53 and the positive rate was 29.2%, but the low differentiation group had the highest positive rate (71.4%). As for tumor invasiveness, the group of outer membrane of esophagus infiltrated had the highest p53 protein positive rate (56%), but in the group, of mucous or submucous layer infiltrated p53 protien was not detectable. The low expression of nm23-H1 and the high expression of p53 were also correlated. The expression of nm23-H1 and p53 were both correlated with TNM stage of esophageal carcinoma (P<0.05). The better esophageal carcinomas differentiated, the lower nm23-H1 expressed and higher p53 expressed. Conclusion Low expression of nm23-H1 and high expression of p53 play an important role in the progression of squamous cell carcinoma of esophagus. Nm23-H1 might beta gene markef in the prophecy of patients' prognosis and benefit tumor treatment clinically.     

Reappraisal of the role of NM23-H1 in colorectal cancers

BACKGROUND AND OBJECTIVES: A number of evidence indicate that downregulation of the nm23-H1 gene may be relevant to metastatic progression of many kinds of human cancer. However, its role in colorectal cancers remains controversial. To address the issue, this study was performed to investigate the clinical relevance of nm23-H1 in patients with colorectal cancers. METHODS: Immunohistochemical expression of nm23-H1 protein product (NM23-H1) was studied in a total of 146 colorectal cancer patients and compared for its prognostic value at a mean follow-up of 54 months. RESULTS: There was no apparent correlation between NM23-H1 expression and clinicopathological indicators, including Dukes category, lymphatic metastasis, distant metastasis, histological grading, and tumor location (P < 0.1, respectively). In addition, determination of NM23-H1 expression status did not provide independent prognostic information compared with conventional pathological staging. CONCLUSIONS: The results indicate that nm23-H1 gene does not play an important part in the progression of colorectal carcinogenesis.     

nm23-H1 expression in nasopharyngeal carcinoma: correlation with clinical outcome

The expression levels of nm23-H1 mRNA and its protein in human nasopharyngeal carcinoma (NPC) were detected to clarify the relationship between nm23-H1 and metastasis and prognosis of patients with NPC. nm23-H1 mRNA expression in fresh tissues from 78 patients with NPC was investigated by in situ hybridization and RT-PCR. Routine labeling streptavidin-biotin immuno-histochemistry with the nm23-H1 murine monoclonal antibody was employed to study the expression of nm23-H1 protein in paraffin-embedded specimens from 231 patients with NPC treated in our hospital. The clinical pathologic data and results of follow-up were collected. Comparisons between expression of nm23-H1 protein or mRNA and clinical outcome were performed using the χ² test. Multivariate prognostic analyses were performed by the Cox regression model. We found that nm23-H1-negative tumors were associated with a higher incidence of lymph-node metastasis (84.2%) than nm23-H1-positive ones (32.8%, p < 0.01). The distant metastasis and loco-regional recurrence rates in the nm23-H1-negative group were 55.8% and 31.68%, respectively but only 17.2% and 11.5%, respectively, in the nm23-H1-positive group (p < 0.01). A significant association was found between expression of nm23-H1 protein and prognosis (p < 0.01). Expression of nm23-H1 protein indicated favorable prognosis, suggesting that the absence of nm23-H1 protein expression was significantly associated with lymph-node metastasis, recurrence and distant metastasis in NPC. Expression of the nm23-H1 gene may be valuable for assessing the prognosis of NPC. Int. J. Cancer (Pred. Oncol.) 79:596–600, 1998. © 1998 Wiley-Liss, Inc.     

nm23-H1基因在喉癌中杂合性丢失和微卫星序列不稳定性分析及表达的研究

目的　探讨nm2 3 H1基因在喉鳞状细胞癌中杂合性丢失 (LOH)及表达情况。方法　选择nm2 3 H1基因内部及附近 5个微卫星多态标记 ,对 72例喉癌标本进行杂合性丢失和微卫星序列不稳定性检测 ,同时以RT PCR方法分析 38例配对喉鳞状细胞癌标本中nm2 3 H1基因表达情况。结果　LOH涉及至少 1个位点的频率高达 76 .39% ,5个位点均有LOH ,以D17S16 6 5处频率最高 ,达 38.10 %。 3个位点出现MI ,最高为 12 .70 %。nm2 3 H1基因杂合性丢失及微卫星不稳定与淋巴结转移、临床分期和肿瘤分化无显著相关性 (P >0 .0 5 ) ,但D17S16 6 5位点高LOH频率与低分化相关 (P <0 .0 5 )。癌、癌旁及转移淋巴结中nm2 3 H1表达不同 ,但差异无统计学意义 ,表达水平与淋巴结转移无关 (P >0 .0 5 )。结论　nm2 3 H1基因可能在喉鳞癌发生中起作用 ,杂合性丢失可能是影响基因功能的主要机制。     

Expression of nm23-Hl and nm23-H2 Proteins in Prostate Carcinoma

The nm 23 gene products/nucleoside diphosphate (NDP) kinase expression in prostate carcinomas and benign hyperplasias was evaluated immunohistochemically. Monoclonal antibodies against nm 23-H1 and nm 23-H2 proteins were prepared using the corresponding proteins fused with glutathione S-transferase as immunogens. Of the 80 cases of nonmetastatic prostate carcinoma examined, 74% (59/80) and 60% (48/80) were immunoreactive for nm 23-H1 or nm 23-H2 protein, respectively. Negative staining for nm 23-H1 occurred in 83% of metastatic lesions, while 34% were negative for nm 23-H2. All primary tumors corresponding to the metastases examined showed positive immunostaining for nm 23-H1, indicating an inverse relationship between expression of this protein and metastatic status. nm 23-H2 protein was detected in 83% of primary tumors and its expression appeared to he significantly correlated to the degree of histological differentiation. In contrast, all cases of benign prostatic hyperplasia showed elevated levels of both nm 23-H1 and nm 23-H2 expression. These data suggest that the nm 23/NDP kinase may play a role in suppressing the expression of malignant potential in prostate carcinomas.     

Correlation between nm23-H1 overexpression and clinicopathological variables in human anal canal carcinoma.

To improve life expectancy prognostic factors other than TNM have been investigated. It is thought that nm23 protein may play a specific biological role in suppressing tumor metastasis. The purpose of this study was to elucidate the clinical significance of nm23 expression in human anal canal carcinoma. Immunostaining using anti-nm23 monoclonal antibody was performed in 22 anal canal tumors. The results were correlated with clinicopathological variables. Six cases out of 22 (27.3%) were nm23-positive. Significant association was found between nm23-H1 expression and depth of invasion, lymph node involvement and prognosis (p<0.05). There was no significant association between nm23-H1 expression, histologic type and age of the patients. nm23-H1 expression was not seen in our cases with metastasis and this may be related to nm23 gene alterations not being detectable by the monoclonal antibody used or to the presence of a subset of tumors in which nm23 gene abnormalities had not yet occurred at the time of tumor excision or biopsy. Overexpression of nm23-H1 protein in anal canal carcinoma may have implications for its metastatic potential. nm23-H1 expression would provide a more accurate evaluation of outcome for individual patients and thus improve treatment planning.     

Expression of nm23-H1 and nm23-H2 protein in endometrial carcinoma.

nm23 gene expression has been shown to be inversely correlated with tumour metastatic potential in some cancers but not in others. Examination was made of the expression of nm23-H1 and nm23-H2 gene products by immunohistochemistry and immunoblotting in 28 endometrial carcinomas. Immunohistochemistry indicated the cytoplasm of cancer cells to be positive, and myometrium and endometrial stromal cells negative, for nm23-H1 and -H2 protein. The staining intensity for these proteins was significantly stronger in well-differentiated adenocarcinomas (G1) than in those moderately differentiated (G2) (P < 0.05). nm23-H1 and -H2 proteins were shown by immunoblotting to be present at significantly higher levels in G1 than in G2 tumours (P < 0.05). Two of eight cases expressed high nm23-H1 and -H2 protein in poorly differentiated adenocarcinomas (G3). In G3 tumours, nm23 expression may be diverse. In this study, the expression of nm23-H1 and -H2 was not correlated with stage, metastasis, tumour size, myometrial invasion, oestrogen receptor, progesterone receptor or menopause. It follows from the findings presented above that the high expression of nm23-H1 and -H2 is positively correlated with histological differentiation.     

卵巢癌高频转移细胞模型中nm23-H1基因表达的相关性研究

目的 筛选高频转移卵巢恶性肿瘤细胞，研究不同转移潜能的细胞和nm23的相关性。方法 通过反复动物接种和体外培养，观察动物肺转移状况，筛选高频转移细胞株，比较原发肿瘤和转移肿瘤的特征，并应用Northera-blot方法测定各类肿瘤细胞nm23 mRNA表达水平。结果 8株卵巢恶性肿瘤细胞中4株有较高转移潜能。多次培养接种可筛选出高频转移细胞亚群。测定各类细胞nm23 mRNA表达水平与肿瘤转移特性呈负相关。结论 由基因分子水平决定的肿瘤转移趋势在不同肿瘤种类及细胞亚群中有明显差异；卵巢癌中nm23 mRNA和蛋白的表达与其转移能力的降低有密切关系，可作为判定卵巢癌预后的敏感指标。     

Identification of a second human nm23 gene, nm23-H2

Reduced RNA and/or protein levels corresponding to the murine nm23-1 and human nm23-H1 complementary DNA clones have been correlated with high tumor metastatic potential in several rodent model systems and human breast carcinomas. We report the identification of a second human nm23 gene, designated nm23-H2. The pNM23-H2S complementary DNA clone predicted a Mr 17,000 protein 88% identical to nm23-H1. nm23-H2 also shared a significant homology with nucleoside diphosphate kinases and a Drosophila developmental gene. Southern blots containing BglII-restricted genomic DNA, which exhibited an allelic restriction fragment length polymorphism for nm23-H1, contained nonallelic bands upon rehybridization to the nm23-H2 probe. Thus, nm23-H1 and nm23-H2 are distinct genes. Northern blot hybridization of nm23-H1- and nm23-H2-specific probes to breast tumors and cell lines indicated that nm23-H1 expression was reduced in high metastatic potential tumor cells to a greater extent than nm23-H2. The data indicate the existence of a family of independently regulated nm23 genes.     

Immunohistochemical detection of nm23-H1/NDP kinase in childhood thyroid carcinoma

Childhood thyroid cancer is known to be aggressive. High incidence of lymph node and distant metastasis are characteristic features of these cases. In adult, reduced expression of nm23-H1/nucleoside diphosphate (NDP) kinase has been correlated with cancer invasion and metastasis in some tumor types. Therefore, we examined the expression of nm23-H1 gene product in childhood thyroid carcinomas in Japan. 27 primary thyroid carcinomas and 8 metastatic lymph nodes were analyzed by immunohistochemistry using monoclonal antibody H1-229. 21 out of 23 cases (91%) of papillary carcinomas were positively immunostained, whereas none of the 4 follicular carcinomas showed any immunoreactivity. No correlation was found between the nm23-H1/NDP kinase antigen expression and nodal involvement or distant metastasis in primary tumors. However, only 50% (4 out of 8) of metastatic lymph nodes from papillary carcinoma were positively stained, demonstrating a significant decrease comparing to those of primary sites. These data indicate that the expression of nm23-H1/NDP kinase cannot predict tumor metastatic potential in childhood thyroid cancer.     

卵巢癌高频转移细胞模型中nm23-H1基因表达的相关性研究

目的筛选高频转移卵巢恶性肿瘤细胞,研究不同转移潜能的细胞和 nm23的相关性。方法通过反复动物接种和体外培养,观察动物肺转移状况,筛选高频转移细胞株,比较原发肿瘤和转移肿瘤的特征,并应用 North-ern-blot 方法测定各类肿瘤细胞 nm23 mRNA 表达水平。结果 8株卵巢恶性肿瘤细胞中4株有较高转移潜能。多次培养接种可筛选出高频转移细胞亚群。测定各类细胞 nm23 mRNA 表达水平与肿瘤转移特性呈负相关。结论由基因分子水平决定的肿瘤转移趋势在不同肿瘤种类及细胞亚群中有明显差异;卵巢癌中 nm23 mRNA 和蛋白的表达与其转移能力的降低有密切关系,可作为判定卵巢癌预后的敏感指标。     

nm23-H1 protein immunohistochemical expression in human breast cancer

A series of 76 patients undergoing surgery for primary breast carcinoma has been prospectively studied in order to evaluate the relative weight of nm23-H1 protein expression in disease-free survival. Expression of nm23 protein was immunohistochemically assessed. In all, 39% (29/74) of the turners showed positive staining for nm23-H1 protein expression. Negative nm23-H1 expression was found in poorly differentiated, tumors (p<0.02). There was no significant relationship between nm23-H1 and the other clinicopathological and biological features examined. In the univariate statistical analysis, node positivity, G3 histological grade and high flow cytometric S phase fraction (SPF) value proved to be significantly related to risk of relapse. In the multivariate analysis, only histological grade (G3) and high SPF values (>10.6) proved to be independently related to risk of relapse, with a hazard ratio of 9.84 and 7.98 respectively. Our preliminary study suggests that immunohistochemical nm23-H1 expression should not be considered a marker for predicting tumor progression and patient prognosis.     

Expression of nm23-H1 in uveal melanoma

Uveal melanoma (UM) is the most common malignant intraocular tumor in adults. Despite the high accuracy of clinical diagnosis and advances in local treatment, more than 50% of UM patients develop metastasis within 10 years of initial diagnosis. NM23 is one of the human metastasis suppressor genes. Reduced nm23-H1 expression is correlated with high metastatic potential in many different cancers. The purpose of this study is to investigate the expression of nm23-H1 in UM and its potential value as a prognostic marker. Immunostaining of nm23-H1 was verified in five human UM cell lines with different metastatic potentials. The expression level of nm23-H1 mRNA was evaluated with one-step quantitative real-time PCR. The invasion ability of the cell lines was assessed before and after silencing nm23-H1 with small interference RNA. Thirty-two cases of paraffin-embedded specimens of human UM were immunostained with nm23-H1 monoclonal antibody. The immunostaining was evaluated in a semiquantitative fashion based on extent and intensity. The real-time PCR results of five human UM cell lines showed that expression of nm23-H1 was higher in cell lines with low metastatic potential compared with those with high metastatic potential (P<0.05). The invasive ability of the UM cell lines increased after silencing nm23-H1 expression with small interference RNA (P<0.05). The immunostaining of nm23-H1 was cytoplasmic in all cell lines and UM patients samples. The increased immunostaining intensity of nm23-H1 in patients' samples was associated with better survival rate (Kaplan-Meier test P=0.0097). The expression of nm23-H1 was not correlated with other prognostic factors. It can be concluded that nm23-H1 may be a prognostic marker to predict the survival rate of UM patients and it has the potential to identify high-risk patients.     

nm23-H1 expression in salivary adenoid cystic carcinoma in relation to metastasis and survival

The expression of nm23-H1, product of putative metastasis suppressor gene, was evaluated immunohistochemically in 31 cases of adenoid cystic carcinoma (ACC) of salivary glands and correlated with their clinicopathologic features. All benign salivary gland tumors of various types, which were used as a non-metastatic control, showed obvious nm23-H1 expression. The immunoreactivity of tumor cells was stronger than that of normal salivary gland components, although the distribution patterns of positive cells considerably varied between tumor types. In ACC, 16 cases (52%) showed the reduction of nm23-H1 immunoreactivity either in positive cell frequency or staining intensity. These cases were referred to as negative cases. The incidence of negative cases was 67% (10/15) and 38% (6/16) of the cases with and without metastasis, respectively. Furthermore, metastatic tumors showed decreased immunoreactivity of this protein compared with their primary tumors. The prognosis of patients with a nm23 negative tumor was generally poorer than that with a positive tumor. These results may suggest that the reduction of nm23-H1 protein has an implication for metastasis of ACC.     

Nm23 and breast cancer metastasis

Summary The majority of breast cancer patients succumb to metastatic disease. We summarize published and recent research concerning thenm23 gene in breast cancer metastasis. In a murine developmental study, nm23 expression increased with the functional differentiation of the mammary gland in nulliparous and pregnant animals. In human breast cancer, five studies have now demonstrated a significant association between reduced nm23 expression, at the RNA or protein levels, and aggressive tumor behavior. Nm23-negative tumor cells have been observed in comedo ductal carcinoma in situ lesions in two independent studies, indicating that decreases innm23 expression begin prior to actual histologically identifiable invasion. Transfection studies, in which humannm23-H1 cDNA was expressed in the metastatic human MDA-MB-435 breast carcinoma cell line, indicate thatnm23-H1 suppresses in vivo metastatic potential by 50-90%. Finally, our data in melanoma and breast carcinoma transfection systems suggest that the biochemical mechanism of nm23 suppressive activity is likely not due to its nucleoside diphosphate kinase activity, association with GAP proteins, or secretion from cells.Supported by an educational grant from CIBA-GEIGY Corp., at the San Antonio Breast Cancer Symposium, Dec. 8, 1992.     

NM23, an example of a metastasis suppressor gene

Metastasis suppressor genes - unlike tumor suppressor genes - are defined by their capacity to control metastatic dissemination in vivo without affecting growth of the primary tumor. The first of these metastasis suppressor genes, NM23, was identified in 1988. Since then, expression of NM23 has been studied widely in human tumor cohorts, often with contradictory results. Not only is NM23 overexpressed in most human solid tumors when compared to healthy tissues, but also low expression of NM23 correlates with metastasis and poor clinical prognosis in the advanced stages of a number of epithelial cancer types, including melanoma, breast, colon, and liver carcinoma. This does not hold true, however, for other cancer types such as neuroblastoma and hematological malignancies, in which high NM23 expression correlates with more aggressive disease. Genetic alterations in the NM23 gene - loss of heterozygosity, spontaneous mutations and polymorphisms - are rarely found in tumors; thus, the metastatic potential of tumor cells is probably affected by NM23 protein levels. Three lines of evidence demonstrate the anti-metastatic activity of NM23: first, overexpression of NM23 in metastatic cell lines reduces their metastatic potential in xenograft models; second, the incidence of lung metastases is elevated in NM23 knockout mice prone to develop hepatocellular carcinoma, and, third, silencing NM23 by RNA interference confers a "metastatic phenotype" on non-invasive human epithelial liver and colon cancer cell lines. It appears that NM23 is crucial for inhibiting invasive migration, so acting at early stages of metastatic dissemination. The mechanistic basis of the metastasis suppressor function of NM23 and its regulated expression still remains obscure, however. Reactivation of expression of the endogenous NM23 gene in tumor cells, or stimulation of the pathways it controls, constitutes a promising avenue for anti-metastatic therapy.