Analysis of nm23 gene expressions in human bladder and renal cancers

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.

Clinical significance of altered nm23-H1, EGFR, RB and p53 expression in bilharzial bladder cancer

Background

Clinical characterization of bladder carcinomas is still inadequate using the standard clinico-pathological prognostic markers. We assessed the correlation between nm23-H1, Rb, EGFR and p53 in relation to the clinical outcome of patients with muscle invasive bilharzial bladder cancer (MI-BBC).

Methods

nm23-H1, Rb, EGFR and p53 expression was assessed in 59 MI-BBC patients using immunohistochemistry and reverse transcription (RT-PCR) and was correlated to the standard clinico-pathological prognostic factors, patient's outcome and the overall survival (OS) rate.

Results

Overexpression of EGFR and p53 proteins was detected in 66.1% and 35.6%; respectively. Loss of nm23-H1and Rb proteins was detected in 42.4% and 57.6%; respectively. Increased EGFR and loss of nm23-H1 RNA were detected in 61.5% and 36.5%; respectively. There was a statistically significant correlation between p53 and EGFR overexpression (p < 0.0001), nm23 loss (protein and RNA), lymph node status (p < 0.0001); between the incidence of local recurrence and EGFR RNA overexpression (p= 0.003) as well as between the incidence of metastasis and altered Rb expression (p = 0.026), p53 overexpression (p < 0.0001) and mutation (p = 0.04). Advanced disease stage correlated significantly with increased EGFR (protein and RNA) (p = 0.003 & 0.01), reduced nm23-H1 RNA (p = 0.02), altered Rb (p = 0.023), and p53 overexpression (p = 0.004). OS rates correlated significantly, in univariate analysis, with p53 overexpression (p = 0.011), increased EGFR (protein and RNA, p = 0.034&0.031), nm23-H1 RNA loss (p = 0.021) and aberrations of ≥ 2 genes. However, multivariate analysis showed that only high EGFR overexpression, metastatic recurrence, high tumor grade and the combination of ≥ 2 affected markers were independent prognostic factors.

Conclusion

nm23-H1, EGFR and p53 could be used as prognostic biomarkers in MI-BBC patients. In addition to the standard pathological prognostic factors, a combination of these markers (≥ 2) has synergistic effects in stratifying patients into variable risk groups. The higher is the number of altered biomarkers, the higher will be the risk of disease progression and death.

Expression of nm23-H1 gene product in sarcomatous cancer cells of renal cell carcinoma: correlation with tumor stage and expression of matrix metalloproteinase-2, matrix metalloproteinase-9, sialyl Lewis X, and c-erbB-2

OBJECTIVES

To investigate the clinical significance of nm23-H1 gene product in sarcomatous cancer cells, because this is known as a tumor-metastasis suppressor. Renal cell carcinoma with sarcomatoid cancer cells is characterized by high malignant potential and a poor prognosis.

METHODS

We investigated the expression of nm23-H1 gene product in the carcinomatous and sarcomatous component (CC and SC) of renal cell carcinoma using immunohistochemical techniques and the relationships between the expression and clinicopathologic features. We also examined the expression of matrix metalloproteinase (MMP)-2, MMP-9, sialyl Lewis X, and c-erbB-2 in the SC because these proteins are regulated by the nm23-H1 gene or its products.

RESULTS

We examined 20 renal cell carcinoma specimens that contained an SC and CC. The CC of 12 of the 20 tumors stained positively for nm23-H1 gene product. In contrast, the SC of only 3 of the 20 stained positive. The reduced expression of nm23-H1 gene product in the SC correlated significantly with tumor invasion (P <0.01), but not with tumor size or metastasis. In contrast, the expression of the nm23-H1 gene product in the CC was not associated with these pathologic features. Expression of the nm23-H1 gene product correlated negatively with MMP-2 expression (r = -0.48, P = 0.03). Other factors did not show such significant correlations with nm23-H1 gene product expression.

CONCLUSIONS

Our results suggest that low expression of nm23-H1 gene products may play important roles in tumor invasion, and that this process is mediated in part by overexpression of MMP-2.

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.

Renal cell carcinoma

Renal cell carcinoma (RCC) is characterized by (a) lack of early warning signs, which results in a high proportion of patients with metastases at the time of diagnosis; (b) protean clinical manifestations; and (c) resistance to radiotherapy and chemotherapy. The estimates of new diagnoses and deaths from kidney cancer in the United States during 1996 are 30,600 and 12,000, respectively. RCC occurs nearly twice as often in men as in women. The age at diagnosis is generally older than 40 years; the median age is in the midsixties. The incidence of RCC has been rising steadily. Between 1974 and 1990, there was a 38% increase in the number of patients who had a diagnosis of RCC. This increase was accompanied by a significant improvement in 5-year survival. Both trends are likely the result of improved diagnostic capability. Newer radiographic techniques, including ultrasonography, computed tomography, and magnetic resonance imaging, are detecting kidney tumors more frequently and at a lower disease stage, when tumors can be resected for cure. Surgical treatment is the only curative therapy for localized RCC. Radical nephrectomy remains the mainstay of surgical management, but techniques are being modified. These modifications include partial nephrectomy and resection of vena caval thrombi. In highly selected cases, surgical resection of locally recurrent RCC or of disease at a solitary metastatic site is associated with long-term survival. Metastatic RCC is highly resistant to the many systemic therapies that have been extensively investigated. A minority of patients achieve complete or partial response to interferon, interleukin-2, or both. Response can be dramatic but is rarely durable. Because most patients do not achieve response, these agents are not considered effective treatments for RCC, but the response in some patients indicates the need for continued research on their use. Identification of new agents with better antitumor activity against metastases remains a high priority in clinical investigation of therapy for this refractory disease.

Expression of the nm23 metastasis-suppressor gene product in skin tumors

Nm23 is a gene with a putative metastasis-suppressor function, whose expression is inversely correlated with the metastatic potential of some solid malignancies. Because very few data exist concerning the role of nm23 in skin tumors, we studied the immunohistochemical expression of nm23 gene product in frozen sections of normal skin and of 104 cutaneous benign or malignant, epithelial and mesenchymal tumors. Nm23 was found expressed within basal cells of the epidermis and its appendages. All basal cell carcinomas showed diffuse immunoreactivity predominating within cells located at the periphery of tumor masses; in contrast, most squamous cell carcinomas, premalignant lesions and the benign epithelial lesions studied showed very weak, if any, immunoreactivity. Benign nevi and most malignant melanomas expressed nm23 immunoreactivity and the pattern observed was similar between primary and metastatic lesions. These results show that nm23 is differentially expressed in cutaneous tumors. It seems likely that the strong immunoreactivity of basal cell carcinomas, contrasting with the almost non-expression in squamous cell carcinomas, reflects the different metastatic potential of these two types of tumors. In melanomas, no direct correlation between the metastatic phenotype and nm23 expression could be detected. Our results suggest that the nm23 gene is involved in cutaneous carcinogenesis; its precise role deserves further study.