Nm23 expression in endometrial and cervical cancer: inverse correlation with lymph node involvement and myometrial invasion

LINC00636 promotes lymph node metastasis and cervical cancer through targeting NM23

BACKGROUND

Metastasis is a major obstacle in treatment of cervical cancer, and long non-coding RNA (lncRNA) mediated regulatory effect on associated genes expression is found to be involved in metastasis. However, its mechanisms have not been fully elucidated.

MATERIALS AND METHODS

Specimens from patients with cervical cancer metastasis and non-metastasis were used to screen out candidate non-coding RNAs (ncRNAs) and possible downstream targets. And then, effects were determined in vitro and in vivo through knockdown and overexpression techniques.

RESULTS

LINC00636 was significantly higher in serum and solid tumor cells of metastatic cervical cancer patients than non-metastatic patients. And knockdown of LINC00636 significantly suppressed invasion, proliferation of cervical cancer cells. NM23 expression was negatively regulated by LINC00636 and it mediated anti-tumor effects was partially blocked by overexpression of LINC00636.

CONCLUSION

LINC00636 might promote metastasis of cervical cancer cells through inhibiting NM23 expression.

Nme1 and Nme2 genes exert metastasis-suppressor activities in a genetically engineered mouse model of UV-induced melanoma

NME1 is a metastasis-suppressor gene (MSG), capable of suppressing metastatic activity in cell lines of melanoma, breast carcinoma and other cancer origins without affecting their growth in culture or as primary tumours. Herein, we selectively ablated the tandemly arranged Nme1 and Nme2 genes to assess their individual impacts on metastatic activity in a mouse model (HGF:p16^−/−) of ultraviolet radiation (UVR)-induced melanoma. Metastatic activity was strongly enhanced in both genders of Nme1- and Nme2-null mice, with stronger activity in females across all genotypes. The study ascribes MSG activity to Nme2 for the first time in an in vivo model of spontaneous cancer, as well as a novel metastasis-suppressor function to Nme1 in the specific context of UVR-induced melanoma.

GOG 8020/210: Risk stratification of lymph node metastasis, disease progression and survival using single nucleotide polymorphisms in endometrial cancer: An NRG oncology/gynecologic oncology group study

OBJECTIVES

The ability to stratify a patient's risk of metastasis and survival permits more refined care. A proof of principle study was undertaken to investigate the relationship between single nucleotide polymorphisms (SNPs) in literature based candidate cancer genes and the risk of nodal metastasis and clinical outcome in endometrioid endometrial cancer (EEC) patients.

METHODS

Surgically-staged EEC patients from the Gynecologic Oncology Group or Washington University School of Medicine with germline DNA available were eligible. Fifty-four genes represented by 384 SNPs, were evaluated by Illumina Custom GoldenGate array. Association with lymph node metastases was the primary outcome. Progression-free survival (PFS) and overall survival (OS) was also evaluated.

RESULTS

361 SNPs with high quality genotype data were evaluated in 337 patients with outcome data. Five SNPs in CXCR2 had an odds ratio (OR) between 0.68 and 0.70 (p-value ≤ 0.025). The A allele rs946486 in ABL had an OR of 1.5 (p-value = 0.01) for metastasis. The G allele in rs7795743 in EGFR had an OR for metastasis of 0.68 (p-value = 0.02) and hazard ratio (HR) for progression of 0.66 (p-value = 0.004). Importantly, no SNP met genome wide significance after adjusting for multiple test correcting and clinical covariates. The A allele in rs2159359 SNP in NME1 and the G allele in rs13222385 in EGFR were associated with worse OS. Both exhibited genome wide significance; rs13222385 remained significant after adjusting for prognostic clinical variables.

CONCLUSION

SNPs in cancer genes including rs2159359 SNP in NME1 and rs13222385 in EGFR may stratify risk in EEC and are prioritized for further investigation.

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.

nm23 regulates decidualization through the PI3K-Akt-mTOR signaling pathways in mice and humans

STUDY QUESTION

Does nm23 have functional significance in decidualization in mice and humans?

SUMMARY ANSWER

nm23 affects decidualization via the phosphoinositide 3 kinase/mammalian target of rapamycin (PI3K-Akt-mTOR) signaling pathways in mouse endometrial stromal cells (ESCs; mESCs) and human ESCs.

WHAT IS KNOWN ALREADY

The function of nm23 in suppressing metastasis has been demonstrated in a variety of cancer types. nm23 also participates in the control of DNA replication and cell proliferation and differentiation.

STUDY DESIGN, SIZE AND DURATION

We first analyzed the expression profile of nm23 in mice during early pregnancy (n = 6/group), pseudopregnancy (n = 6/group) and artificial decidualization (n = 6/group) and in humans during the menstrual cycle phases and the first trimester. We then used primary cultured mESCs and a human ESC line, T-HESC, to explore the hormonal regulation of nm23 and the roles of nm23 in in vitro decidualization, and as a possible mediator of downstream PI3K-Akt-mTOR signaling pathways.

PARTICIPANTS/MATERIALS, SETTINGS AND METHODS

We evaluated the dynamic expression of nm23 in mice and humans using immunohistochemistry, western blot and real-time quantitative RT-PCR (RT-qPCR). Regulation of nm23 by steroid hormones was investigated in isolated primary mESCs and T-HESCs by western blot. The effect of nm23 knockdown (using siRNA) on ESC proliferation was analyzed by 5-ethynyl-2'-deoxyuridine staining (EdU) and proliferating cell nuclear antigen protein (PCNA) expression. The influence of nm23 expression on the differentiation of ESCs was determined by RT-qPCR using the mouse differentiation markers decidual/trophoblast PRL-related protein (dtprp, also named prl8a2) and prolactin family 3 subfamily c member 1 (prl3c1) and the human differentiation markers insulin-like growth factor binding protein 1 (IGFBP1) and prolactin (PRL). The effects of nm23 siRNA (si-nm23) and the PI3K inhibitor LY294002 on the downstream effects of nm23 on the PI3K-Akt-mTOR signaling pathway were estimated by western blot.

MAIN RESULTS AND THE ROLE OF CHANCE

NM23-M1 was specifically expressed in the decidual zone during early pregnancy and in artificially induced deciduoma, and NM23-H1 was strongly expressed in human first trimester decidua. The expression of nm23 was upregulated by oestradiol and progesterone (P < 0.05 versus control) in vitro in mESCs and T-HESC, and this was inhibited by their respective receptor antagonists, ICI 182,780 and RU486. Mouse and human nm23 knockdown decreased ESC proliferation and differentiation (P < 0.05 versus control). The PI3K-Akt-mTOR signaling pathways were downstream mediators of nm23 in mESCs and T-HESCs decidualization.

LIMITATIONS AND REASONS FOR CAUTION

Whether the nm23 regulates decidualization via the activation of AMPK, RAS, PKA, STAT3 or other signaling molecules remains to be determined. The role of nm23 in decidualization was tested in vitro only.

WIDER IMPLICATIONS OF THE FINDINGS

Results demonstrate that nm23 plays a vital role in decidualization in mice and humans and that nm23 gene expression is hormonally regulated. The downregulation of nm23 in decidua during the first trimester may be associated with infertility in women.

STUDY FUNDING/COMPETING INTERESTS

This study was supported by the National Natural Science Foundation of China (grant nos. 81370731, 31571551 and 31571190), the Science and Technology Project of Chongqing Education Committee (KJ130309), open funding by the Chongqing Institute for Family Planning (1201) and the Excellent Young Scholars of Chongqing Medical University (CQYQ201302). The authors have no conflicts of interest to declare.

NME2 reduces proliferation, migration and invasion of gastric cancer cells to limit metastasis

Gastric cancer is one of the most common malignancies and has a high rate of metastasis. We hypothesize that NME2 (Nucleoside Diphosphate Kinase 2), which has previously been considered as an anti-metastatic gene, plays a role in the invasiveness of gastric cancer cells. Using a tissue chip technology and immunohistochemistry, we demonstrated that NME2 expression was associated with levels of differentiation of gastric cancer cells and their metastasis into the lymph nodes. When the NME2 gene product was over-expressed by ;in vitro stable transfection, cells from BGC823 and MKN45 gastric cancer cell lines had reduced rates of proliferation, migration, and invasion through the collagen matrix, suggesting an inhibitory activity of NME2 in the propagation and invasion of gastric cancer. NME2 could, therefore, severe as a risk marker for gastric cancer invasiveness and a potential new target for gene therapy to enhance or induce NME2 expression.

Regulatory functions of Nm23-H2 in tumorigenesis: insights from biochemical to clinical perspectives

Substantial effort has been directed at elucidating the functions of the products of the Nm23 tumor metastasis suppressor genes over the past two decades, with the ultimate goal of exploring their translational potentials in changing cancer patients' outcomes. Much attention has been focused on the better-known Nm23-H1, but despite having high sequence similarity, Nm23-H2 functions differently in many aspects. Besides acting as a metastasis suppressor, compelling data suggest that Nm23-H2 may modulate various tumor-associated biological events to enhance tumorigenesis in human solid tumors and hematological malignancies. Linkage to tumorigenesis may occur through the ability of Nm23-H2 to regulate transcription, cell proliferation, apoptosis, differentiation, and telomerase activity. In this review, we examine the linkages of Nm23-H2 to tumorigenesis in terms of its biochemical and structural properties and discuss its potential role in various tumor-associated events.

Engineered reversal of drug resistance in cancer cells--metastases suppressor factors as change agents

Building molecular correlates of drug resistance in cancer and exploiting them for therapeutic intervention remains a pressing clinical need. To identify factors that impact drug resistance herein we built a model that couples inherent cell-based response toward drugs with transcriptomes of resistant/sensitive cells. To test this model, we focused on a group of genes called metastasis suppressor genes (MSGs) that influence aggressiveness and metastatic potential of cancers. Interestingly, modeling of 84 000 drug response transcriptome combinations predicted multiple MSGs to be associated with resistance of different cell types and drugs. As a case study, on inducing MSG levels in a drug resistant breast cancer line resistance to anticancer drugs caerulomycin, camptothecin and topotecan decreased by more than 50–60%, in both culture conditions and also in tumors generated in mice, in contrast to control un-induced cells. To our knowledge, this is the first demonstration of engineered reversal of drug resistance in cancer cells based on a model that exploits inherent cellular response profiles.

Mechanisms of non-metastatic 2 (NME2)-mediated control of metastasis across tumor types

Non-metastatic 23 [NM23/nucleoside diphosphate kinases (NDPK)] genes are the first discovered metastasis suppressor genes. More than two decades of research has demonstrated their roles in a variety of biological processes with NME1 and NME2 being most studied in the context of metastasis suppression. Although NME1 and NME2 share >85% homology at amino acid level, they show redundant as well as unique molecular functions. Phenotypic analyses of knockout (KO) mice for NM23 members (NDPK-A, B) and compound KO (A as well as B) showed requirement of both proteins in hematopoiesis suggesting shared functions in development disease. Several reviews have discussed NME1, however the role of NME2 appears to be relatively less understood in the context of metastasis suppression. Here, we focus on NME2 and by meta-analysis of gene expression from multiple tumor types, and survey of in vivo and vitro studies, suggest the possibility that NME2 may be one of the key factors in metastasis. This along with the relevance of normal physiological functions of NME2 in the context of metastasis is discussed. We further examined the genetic and epigenetic features of NME2 and NME1 gene promoters and found aspects of transcription control that could be unique to NME2/NME1. Findings on signaling pathways and small molecules which regulate the expression of NME2 that could be therapeutically important are also discussed.

Gene profiling in Pap-cell smears of high-risk human papillomavirus-positive squamous cervical carcinoma

OBJECTIVE

The purpose of the study was to investigate benign and malignant squamous cervical cells obtained by cervical swabs with regard to differentially expressed genes and gene expression profiling, in order to evaluate the biological behavior and clinical outcome of cervical malignancies.

METHODS

Cervical squamous cells from six women with high-risk human papillomavirus positive [HR-HPV(+)] cervical carcinoma and from six HPV-negative women with normal ectocervical cells were analyzed by cDNA array.

RESULTS

cDNA over-expression of several genes such as MET (c-met), Nm23-H1 (NME1), EGFR, KGFR, Nm23-H2 (NME2), ERBB2 (c-erbB-2), cyclin-dependent kinase inhibitor 4 (CDKN2A, p16INK4A), cytokeratin 8 (KRT8), KRAS (K-ras), FLT1, KGF (FGF7), BCL2-like 2 protein (BCL2L2), ERBB4, MYCN (N-myc), cyclin D1 (CCND1), KIT (c-kit), secreted phosphoprotein 1 (SPP1) and STAT1, was significant in cervical squamous cell carcinoma (CSCC). Gene expression was downregulated for 13 genes in CSCC, such as interleukin 1 alpha (IL1A), the transforming growth factor receptor beta superfamily (TGFbeta; TGFB), some members of the insulin-like growth factor binding proteins (IGFBPs) and the integrin family (ITGA6, ITGB1).

CONCLUSION

This study was focused on the gene expression profiling of HR-HPV(-) and (+) cervical squamous cells and CSCC obtained by cytobrush. We observed gene expression patterns and signaling pathways that permit the investigator to distinguish between benign squamous cervical cells and CSCC with and without HPV infection.

Nm23-H1: a metastasis-associated gene

The protein product of nm23-H1 gene has activity of nucleoside diphosphate (NDP) kinase, which catalyzes the phosphorylation of nucleoside diphosphates to the corresponding nucleoside triphosphates. Reductions in nm23 expression have been significantly associated with aggressive behavior in melanoma, breast, colon, and gastric carcinomas. On the contrary, high levels of nm23 gene expression are noted in the advanced stage of thyroid carcinomas and associated with significant reductions in survival for neuroblastoma and osteosarcoma patients. Although expression of nm23/NDP kinase is divergent in various malignant tumors, its reduced expression seems to be related to increased metastatic potential in most carcinoma types. However, it is hypothesized that nm23 may play a tissue-specific role, and that different regulatory mechanisms may act in different tumors. In ovarian carcinoma, nm23-H1/NDP kinase may be correlated with some clinicopathologic characteristics. In cervical cancer, nm23-H1 is probably involved in cervical carcinogenesis and correlated with some aggressive parameters. Overexpression of nm23-H1 protein may indicate poor survival for cervical cancer patients. Other than histidine 118 residue (amino acid sequence 118: histidine) concerned with NDP kinase activity of nm23-H1, serine 120 (amino acid sequence 120: serine) related activity of histidine-dependent protein phosphotransfer was recently reported to be responsible for its biological suppressive effects. To inhibit metastatic potential, nm23-H1 is also demonstrated to co-immunoprecipitate the kinase suppressor of Ras and phosphorylate it, and therefore reduce activation of the extracellular signal-regulated kinase mitogen-activated protein kinase pathway in response to signaling.

Down-regulated nucleoside diphosphate kinase nm23-H1 expression is unrelated to high-risk human papillomavirus but associated with progression of cervical intraepithelial neoplasia and unfavourable prognosis in cervical cancer

OBJECTIVE

One of the factors leading to an invasive phenotype is the nm23 family of metastases-associated genes. Of the six known members, nm23-H1 is the most frequently studied potential anti-metastatic gene in cervical cancer. However, the possible molecular links to oncogenic human papillomavirus (HPV) are completely unexplored as yet.

MATERIALS AND METHODS

As a part of the HPV-Pathogen Istituto Superiore di Sanità study, a series of 150 squamous cell carcinomas (SCCs) and 152 cervical intraepithelial neoplasia (CIN) lesions were examined by immunohistochemical staining for nm23-H1, and tested for HPV by polymerase chain reaction (PCR) with three sets of primers (MY09/11, GP5(+)/GP6(+) and short PCR fragment). Follow-up data were available on all patients with SCC, and 67 CIN lesions were monitored by serial PCR for clearance or persistence of HPV after cone treatment.

RESULTS

A linear decrease (p = 0.001) was observed in nm23-H1 expression, starting from CIN1 (85% with normal expression), with the most dramatic down regulation on transition from CIN2 (70% normal) to CIN3 (39%) and further to SCC (25%). Reduced expression was associated with CIN3 or cancer at an odds ratio 8.72 (95% confidence interval 4.13 to 18.41). Nm23-H1 was of no use as a marker of the high-risk human papillomavirus (HR-HPV) type, and it did not predict clearance or persistence of HR-HPV after treatment of CIN. Importantly, nm23-H1 expression was a significant prognostic factor in cervical cancer, reduced expression being associated with lower survival (p = 0.022) in univariate analysis. In the multivariate (Cox) regression model, however, only the International Federation of Gynecology and Obstetrics stage (p = 0.001) and age (p = 0.011) remained independent prognostic predictors.

CONCLUSIONS

Down-regulated nm23-H1 expression is markedly associated with progression from CIN2 to CIN3, and predicts poor prognosis in cervical cancer. Nm23-H1 down regulation is probably orchestrated by mechanisms independent of HR-HPV oncoproteins and is possibly related to the emergence of a proteolytic phenotype.

Statistical analysis of pathologic risk factors for intramyometrial lymphvascular space involvement in myoinvasive endometrial carcinoma

In a retrospective study using univariate analysis, we identified tumor type (nonendometrioid vs endometrioid), depth of myoinvasion (MI), mode of MI (infiltrative vs cohesive), and direct anatomic invasion of the cervical wall from the isthmus as significant positive risk factors for intramyometrial lymphvascular space involvement (LVSI). On multivariate analysis, tumor grade, depth of MI, and mode of MI retained their significance. We created a grid for the relative risks of LVSI with respect to these variables individually or in combination. We suggest that our indirect estimate of the risk of LVSI can help in assessing prognosis and determining the need for adjuvant therapy whenever LVSI is important in clinical decision making, but its pathologic diagnosis is uncertain.

Regulation of metastasis-suppressive gene Nm23-H1 on glycosyl-transferases involved in the synthesis of sialyl Lewis antigens

By using reverse transcriptase-polymerase chain reaction (RT-PCR), the mRNA expressions of three families of glycosyltransferases involved in the synthesis of sialyl Lewis antigens were determined in H7721 human hepatocarcinoma cell line before and after the transfection of metastasis-suppressive gene nm23-H1. These glycosyltransferases included alpha1,3fucosyltransferase (alpha1,3FucT)-III, -IV, -VI, -VII, and -IX, alpha2,3-sialyltransferase (ST3Gal)-I, -II, -III, and -IV as well as O-glycan core 2 beta1,6 N-acetylglucosaminyltransferase (C2GnT)-I and -II. In mock cells transfected with the vector, the expression-order of alpha1,3FucTs was IV>VI>III>VII>IX, that of ST3Gals was IV>I>II>III, and that of C2GnT was I>II. Nm23-H1 downregulated the mRNA expressions of all five subtypes of alpha1,3FucT and -I, -III, -IV subtypes of ST3Gal, but not ST3Gal-II and C2GnT-I, II. On the other hand, the expressions of cell surface sialyl Lewis X (SLe(x)) and alpha2,3 sialyl residues were decreased on nm23-H1 transfected cells as detected with monoclonal antibody of SLe(x) and enzyme-labeled lectins, respectively. Since SLe(x) was reported to be a metastasis-associated glycan structure, the reduced expressions of SLe(x) and some enzymes related to its synthesis may be one of the mechanisms to explain the metastasis-suppressive effect of nm23-H1.

cDNA array analysis of cytobrush-collected normal and malignant cervical epithelial cells: a feasibility study

Analysis of gene expression pattern is a useful approach to evaluating the biological behavior and clinical outcome of several human malignancies. Differentially expressed genes in malignant squamous cervical cells and the feasibility of gene expression profiling on squamous cervical cells obtained from cervical swabs were investigated. Cervical squamous cells from three women with high-risk human papilloma virus (HR-HPV) positive invasive squamous cervical carcinoma and from three HPV-negative women with normal ectocervical smears were analyzed with cDNA array. Immunoblot analysis was performed to detect the proteins corresponding to the highest upregulated genes with cDNA array. mRNA expression of ERBB2, KIT, FLT1, MYCN, RAS, CDKN2A, CCND1, NME1, NME2, MET, FGF7, FGFR2, and STAT1 was increased in malignant samples. Several expressed genes associated with antiapoptosis (such as BCL2), cell structuring, or cell attachment were also upregulated in carcinoma cells. Decreased gene expression was observed for members of the transforming growth factor receptor superfamily (TGF) and integrin family, interleukin 1 (IL1), and insulin-like growth factor binding proteins (IGFBPs). This study shows the feasibility of gene expression profiling of cervical squamous cells obtained with cytobrushes by identifying a characteristic gene expression pattern that clearly distinguishes between malignant and normal cervical epithelia of squamous type. We hypothesize that this noninvasive technique could be used in the evaluation of ambiguous Papanicolaou (PAP) smears.

Effect of N-acetylglucosaminyltransferase V on the expressions of other glycosyltransferases

Transfection of sense cDNA of N-acetylglucosaminyltransferase V (GnTV) into H7721 human hepatocellular carcinoma cells resulted in the decreased expression of surface sialyl Lewis X (SLe(x)), a sialylated fucose-containing antigen. The enzymatic mechanisms were speculated to be the concomitantly decreased expression of alpha1,3-fucosyltransferase (FucT)-III, -VI, -VII and the branching enzyme of O-glycans, core 2-beta1,6-N-acetylglucosaminyltransferase (C2GnT)-I, -II. These two glycosyltransferase families were suggested to be the key enzymes in the synthesis of SLe(x). The expression of alpha2,3-sialyltransferase (ST3)-IV, but not ST3-I, -II and -III was elevated by sense GnTV. However, it did not cause the increase of SLe(x) synthesis. Transfection of antisense GnTV into H7721 cells showed entirely opposite effects on the expression of above-mentioned SLe(x) and glycosyltransferases as the sense GnTV.

Nm23-H1 immunohistochemical expression in multisteps of cervical carcinogenesis

To evaluate the expression of nm23-H1 protein in normal, precancerous, and cancerous tissues of the uterine cervix and its role in cervical carcinogenesis, metastasis and recurrence, 82 cervical specimens, including 30 squamous cell carcinomas (SCC), 19 high- and 13 low-grade squamous intraepithelial lesions (HSILs and LSILs) and 20 normal samples, were stained using immunohistochemical method with streptavidin-biotin peroxidase immunostaining. The Chi-square and Fisher's exact tests, as well as Chi-square test for trend, were used for comparing nm23-H1 expression among normal, LSIL, HSIL, and cancerous tissues. The correlation of nm23 expression with metastasis or recurrence was analyzed using Fisher's exact test. There were significant differences in levels of nm23-H1 expression between LSIL and HSIL (P = 0.016) and between LSIL and SCC (P = 0.004), but not between HSIL and SCC or normal and LSIL samples. Furthermore, a positive relationship was demonstrated for high nm23-H1 protein expression and degree of malignant transformation (P < 0.05). Among the 30 SCC cases, high nm23-H1 expression did not show significant association with either carcinomatous metastasis or recurrence (P = 0.123, 0.372, respectively). High nm23-H1 expression appears related to critical progression of LSIL to HSIL but not to metastasis or recurrence of SCC.

Clinical significance of nm23 expression and chromosome 17 numerical aberrations in primary gastric cancer

The metastasis suppressor gene nm23 located on chromosome 17 might be one of the targets in deletions of chromosome 17. In this study, we analyzed the expression of nm23 and chromosome 17 aberrations in gastric cancer and assessed their clinicopathological and prognostic significance. In 103 gastric cancer patients, we examined nm23 expression by immunohistochemistry and detected chromosome 17 aberrations by fluorescence in situ hybridization. There was a significant difference in the expression of nm23 among differentiated histologic types (well > moderately > poorly) (p < 0.01). Negative expression of nm23 correlated with depth of invasion (p < 0.01), lymph node metastasis (p < 0.05), lymphatic invasion (p < 0.05), venous invasion (p < 0.05), poor prognosis (p < 0.05), and chromosome 17 loss (p < 0.05). Chromosome 17 aberrations broadly correlated with clinicopathological variables and were associated with poor prognosis (p < 0.05). Univariate analyses identified nm23 (p < 0.05), chromosome 17 aberrations (p < 0.05), tumor size (p < 0.01), depth of invasion (p < 0.0001), lymph node metastasis (P < 0.001), hepatic metastasis (p < 0.01), peritoneal dissemination (p < 0.01), and lymphatic invasion (p < 0.01) as significant prognostic factors. Multivariate analysis showed that expression of nm23 and chromosome 17 aberrations were not independent prognostic indicators. Our results indicate that negative expression of nm23 and chromosome 17 numerical aberrations correlate with tumor progression and poor prognosis but are not independent prognostic indicators.

Prognostic role of nm23 gene expression in patients with ovarian cancer

The aim of the study was to define the prognostic role of the metastasis suppressor gene, nm23, in 50 patients with primary ovarian cancer. Immunohistochemical analysis was performed on formalin-fixed, paraffin-embedded specimens by the primary nm23 monoclonal antibody (Novocastra, NCL-nm23 clone 37.6). Forty-two specimens (84%) showed a positive nm23 staining. The nm23 staining was more intensive in patients with normal serum CA19.9 levels, patients with nonrecurrent disease, and alive patients (p < 0.05). Nm23 expression did not correlate with common clinicopathologic parameters such as histology, grade of differentiation, International Federation of Gynecology and Obstetrics stage, and CA-125. Although the difference was not statistically significant (p = 0.11), we found that nm23 may have a favorable prognostic factor in ovarian cancer. To clarify this subject further, prospective studies on a larger population are needed.

KAI1 metastasis suppressor gene is frequently down-regulated in cervical carcinoma

KAI1 is a metastasis suppressor gene located on human chromosome 11p11.2. It belongs to a structurally distinct family of cell surface glycoproteins. Decreased KAI1 expression has been observed in several common solid epithelial tumors, including prostatic, pancreatic, lung, hepatic, colorectal, ovarian, and esophageal cancers. A recent study also observed frequent loss of KAI1 expression in a number of squamous cell carcinomas of the cervix by immunohistochemical technique. To further confirm whether this gene is altered in this malignancy, we analyzed KAI1 expression in various stages of cervical carcinoma by a molecular method. Total cellular RNA was extracted from 84 primary invasive cervical carcinomas and 6 metastatic or recurrent lesions. cDNA was synthesized and was used for real-time quantitative polymerase chain reaction analysis. The level of KAI1 expression was obtained as the value of threshold cycle (Ct) and was quantitated with a comparative Ct method. In addition, paraffin blocks of the tumors were selected and prepared for immunohistochemical study with an anti-KAI1 polyclonal antibody, C-16. Both the real-time quantitative polymerase chain reaction method and immunohistochemical study revealed a frequent decrease in KAI1 expression in invasive cervical cancers and metastatic or recurrent lesions. However, the reduction in KAI1 was not related to progression of the disease. When tumor cell differentiation was analyzed, poorly differentiated tumors showed a greater decrease in KAI1 expression than well or moderately differentiated tumors (P < 0.001). Histologically, KAI1 loss was observed equally in both squamous cell carcinoma and adeno-/adenosquamous carcinoma. Since down-regulation of KAI1 occurs in both early and late stages of cervical cancer, we suggest that its involvement in the progression of this malignancy is an early event.

Current molecular aspects of the carcinogenesis of the uterine endometrium

Carcinogenesis in many tissues is a multistep process accompanied by a variety of morphologic, biochemical, and genetic changes in each step. It is well known that endometrial cancers arise through a series of precursor lesions, simple, complex, and atypical hyperplasia, by unopposed and prolonged estrogen stimulation. It is also accepted that there is an estrogen-independent type in which the precursor lesions are not identified. Recent molecular-based evidence has revealed three possible pathways for endometrial carcinogenesis, namely hyperplasia, metaplasia, and de novo pathways. The pathways each have their own features in both histopathology and molecular biology. Such understanding of the molecular profile of endometrial carcinoma prompted us to revise the classic criteria in histopathology regarding endometrial carcinogenesis. The recent molecular-based studies have provided a concept of endometrial intraepithelial lesions: endometrial intraepithelial neoplasia (EIN) as the precursor lesions of endometrial carcinomas. The new terminology might improve cancer screening protocols and treatment modalities.

Transfection of the c-erbB2/neu gene upregulates the expression of sialyl Lewis X, alpha1,3-fucosyltransferase VII, and metastatic potential in a human hepatocarcinoma cell line

The pCMV4 plasmid containing the cancer-promoting gene, c-erbB2/neu, was cotransfected into the human hepatocarcinoma cell line 7721 with the pcDNA3 vector, which contains the 'neo' selectable marker. Several clones showing stable expression of c-erbB2/neu were established and characterized by determination of c-erbB2/neu mRNA and its encoded protein p185. Expression of Lewis antigens and alpha1,3-fucosyltransferases and the biological behavior of 7721 cells after c-erbB2/neu transfection were studied using mock cells transfected with the vectors pCMV4 and pcDNA3 as controls. SLe(x) expression on the surface of mock cells was high, whereas expression of SDLe(x), Lex and SLe(a) was absent or negligible. This is compatible with the abundant expression of alpha1,3-fucosyltransferase VII, very low expression of alphafucosyltransferase III/VI, and almost absent expression of alpha1,3-fucosyltransferase IV in the mock cells. After transfection of c-erbB2/neu, expression of SLe(x) and alpha1,3-fucosyltransferase VII were simultaneously elevated, but that of alphafucosyltransferase III/VI was not altered. The expression of both SLe(x) and alpha1,3-fucosyltransferase VII correlated positively with the expression of c-erbB2/neu in different clones, being highest in clone 13, medium in clone 6, and lowest in clone 7. In addition, the adhesion of 7721 cells to human umbilical vein endothelial cells (HUVECs) or P-selectin, as well as cell migration and invasion, were increased in c-erbB2/neu-transfected cells. These increases also correlated positively with the expression intensities of c-erbB2/neu, SLe(x) and alpha1,3-fucosyltransferase VII in the different clones, whereas cell adhesion to fibronectin correlated negatively with these variables. mAbs to SLe(x) (KM93) and SDLe(x) (FH6) significantly and slightly, respectively, abolished cell adhesion to HUVECs or P-selectin and cell migration and invasion. mAbs to SDLe(x) and SLe(a) did not suppress cell adhesion to HUVECs nor inhibit cell migration and invasion. Transfection of alpha1,3-fucosyltransferase VII cDNA into 7721 cells showed similar results to transfection of c-erbB2/neu, and the increased adhesion to HUVECs, cell migration, and invasion were also inhibited significantly by KM93 and slightly by FH6. These results indicate that expression of alpha1,3-fucosyltransferase VII and its specific product, SLe(x), and their capacity for cell adhesion, migration and invasion are closely related. Therefore, the c-erbB2/neu gene is proposed to be a metastasis-promoting gene, and its effects are at least partially mediated by the increased expression of alpha1,3-fucosyltransferase VII and SLe(x).

Expression of nm23-H1 gene product in esophageal squamous cell carcinoma and its association with vessel invasion and survival

BACKGROUND

We assessed the nm23-H1 gene product expression and its relationship with lymphatic and blood vessel invasion in patients with esophageal squamous cell carcinoma.

METHODS

Formalin-fixed and paraffin-embedded tissue sections from 45 patients who were treated surgically were used in this study. Pathologists graded lymphatic and blood vessel invasion in each of the tissue samples. Expression of nm23-Hl gene product was determined using a specific monoclonal antibody.

RESULTS

Expression of nm23-H1 gene product was present in 17 (37.8%) cases. We found an inverse correlation between nm23-H1 gene product expression and lymphatic vessel invasion, whereas no correlation between nm23-H1 gene product expression and blood vessel invasion. Overall survival rate was not different between nm23-H1 gene product positive and negative patients (p = 0.21). However, reduced expression of nm23-H1 gene product was associated with shorter overall survival in patients with involved lymph nodes (p < 0.05), but not in patients without involved lymph nodes (p = 0.87).

CONCLUSIONS

In patients with esophageal squamous cell carcinoma, there appears to be an inverse relationship between nm23-H1 gene product expression and lymphatic vessel invasion. Furthermore, nm23-H1 gene product expression might be a prognostic marker in patients with involved lymph nodes. Our data does not demonstrate any correlation between nm23-H1 gene product expression and blood vessel invasion.

The predictive value of vascular endothelial growth factor and nm23 for the diagnosis of occult metastasis in non-small cell lung cancer

We assessed the association of vascular endothelial growth factor (VEGF) and nm23 expression with occult micrometastasis in lung cancer. As destination sites for micrometastasis, we scrutinized lymph node (LN) and bone marrow (BM) specimens. For LN, 122 stage I patients who had received curative operations were studied. As regards BM, 203 patients in stage I - IV who underwent operations were registered. Immunohistochemical anti-cytokeratin staining was used to detect microdissemination of cancer cells. The VEGF and the nm23 expression at the primary sites were immunohistochemically studied in 285 cases in total. The percentages of the patients with microdissemination were 28.7% for LN and 42.4% for BM. The outcome for the patients with LN or BM microdissemination was significantly worse than that for patients without it. The increased VEGF and the decreased nm23 expression within primary tumors were significantly associated with LN and BM microdissemination. The results indicate possible value of using these biological markers to predict the risk of systemic micrometastasis in non-small cell lung cancer.

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.

Down-regulation of N-acetylglucosaminyltransferase V by tumorigenesis- or metastasis-suppressor gene and its relation to metastatic potential of human hepatocarcinoma cells

The effects of transfection of the metastasis suppressor gene nm23-H1 and cell-cycle related tumor-suppressor gene p16 on the activity of N-acetylglucosaminyltransferase V (GnT-V) and their relations to cancer metastatic potential were investigated. After transfection of nm23-H1 into 7721 human hepatocarcinoma cells and A549 human lung cancer cells, the activities of GnT-V were decreased by 28%-42% in the cells. In contrast, when p16 was transfected into these two cell lines, the decrease of GnT-V activity was only observed in A549 cells. This was probably to be due to the obvious expression of p16 gene in parental 7721 cells and the deletion of p16 in A549 cells. The decrease of GnT-V mRNA was only observed in nm23-H1-transfected cells, but not in p16-transfected A549 cells, suggesting that these two genes regulated GnT-V via different mechanisms. Horseradish peroxidase (HRP)-lectin staining showed that the 7721 cells transfected with nm23-H1 or the A549 cells transfected with p16 displayed a decreased intensity with HRP-leucoagglutinating phytohemagglutinin and increased intensity with HRP-concanavalin A, indicating the decline of beta1,6 N-acetylglucosamine branching structure on the asparagine-linked glycans of cell-surface and intracellular glycoproteins. The nm23-H1 transfected 7721 cells also displayed some changes in metastasis-related phenotypes, including the increase in cell adhesion to fibronectin (Fn), the decline in cell adhesion to laminin (Ln), and the decreased cell migration and invasion through matrigel. Transfection of antisense GnT-V cDNA into 7721 cells resulted in a decrease of GnT-V activity, an increase of cell adhesion to Fn or Ln, and a decrease in cell migration and invasion through matrigel. These phenotypes bore similarity to those of the 7721 cells transfected with nm23-H1. Our findings indicate that the down-regulation of GnT-V by nm23-H1 contributes to the alterations in metastasis-related phenotypes, and is an important molecular mechanism of metastasis suppression mediated by nm23-H1.

Modulation of the basal activity of phosphatidylinositol-3-kinase/protein kinase B signaling pathway in human hepatocarcinoma cells

The modulation of GnT-V activity by signaling molecules in PI-3-K/PKB pathway in human hepatocarcinoma cell line 7721 was studied. GnT-V activity was determined after the transfection of sense or antisense cDNA of PKB into the cells, as well as the addition of activators, specific inhibitors, and the antibodies to the enzyme assay system or culture medium. It was found that the basal activity of GnT-V was up regulated by the sense and down regulated by the antisense cDNA of PKB transfected into 7721 cells. GnT-V was activated by PIP2, PIP3 or GTPgamma[S] added to the assay system, and the activation of PIP2 or GTPgamma[S] was abolished by LY2940002, a specific inhibitor of PI-3-K, but the activation of PIP3 was not attenuated by LY2940002. In addition, GnT-V activity in cultured parental or H-ras transfected cells was inhibited by the antibody against PKB or PI-3-K. These findings demonstrated the involvement of PI-3-K/PKB signaling pathway in the regulation of GnT-V. Moreover, ET18-OCH3, an inhibitor of Raf translocation and PI-PLC enzyme, which produces the activator of PKC, as well as the antibodies against Raf-1 or MEK also inhibited GnT-V activity in the parental and H-ras transfected cells. The inhibitory rates, however, were less in the transfected cells than those in the parental cells. These results reveal that in parental and H-ras transfected 7721 cells, the basal activity of GnT-V is also regulated by the Ras/Raf-1/MEK/MAPK cascade in addition to PI-3-K/PKB signaling pathway. The significance of these two pathways in the regulation of GnT-V and their relations to the activation of PKC previously reported by our laboratory (Ju TZ et al., 1995 Glyconjugate J 12, 767-772) was discussed.

Increased vascular endothelial growth factor and vascular endothelial growth factor-c and decreased nm23 expression associated with microdissemination in the lymph nodes in stage I non-small cell lung cancer

OBJECTIVE

We examined a microdissemination of cancer cells in lymph nodes and assessed its clinical and biologic characteristics.

METHODS

Both primary tumors and lymph nodes (2030 nodes) were obtained from 122 patients with primary stage I lung cancer who underwent curative operations with routine systematic nodal dissection of both the hilar and the mediastinal nodes. Immunohistochemical anticytokeratin staining was used to detect nodal microdissemination of cancer cells. Vascular endothelial growth factor, vascular endothelial growth factor type C, and nm23 expression at primary sites were also immunohistochemically studied.

RESULTS

In total, 35 patients (29%) had cytokeratin-positive cells in lymph nodes. Increased expression of vascular endothelial growth factor (P =.0001) and vascular endothelial growth factor type C (P <. 0001) at primary sites were significantly associated with nodal microdissemination, and nm23 was inversely correlated with microdissemination (P =.008). The 3- and 5-year survivals for the patients with nodal microdissemination were 57% and 54%, respectively, which was a significantly worse prognosis as compared with those prognoses (83% and 76%) for the patients without nodal microdissemination (P =.006). The independent prognostic impact of nodal microdissemination was not clear; however, vascular endothelial growth factor retained independent significance.

CONCLUSION

All of these findings lead us to conclude that the microspread of tumor cells in nodes detected by immunohistochemical anticytokeratin staining is definitely a metastasis with a high risk of systemic disease.

H-ras and Nm23-H1 gene expression and proteolytic activity in squamous cell carcinoma of the uterine cervix

BACKGROUND

The invasive and metastatic potential of malignant cells results from complex interactions of numerous factors not yet fully understood. Genomic alterations such as ras overexpression and nm23-H1 inhibition have been found to be frequently associated with increased invasiveness in various cancers. On the other hand, secretion of different proteinases are necessary for malignant cells to traverse a network of matrix macromolecules, but the relationship between the genomic alterations and the proteolytic phenotype is still unclear. Our aim was to investigate whether the appearance of the proteolytic phenotype had any correlation with the expression of H-ras and nm23-H1 genes in carcinoma of the uterine cervix.

METHODS

Twenty-five samples from patients with carcinoma of the uterine cervix at different clinical stages were studied. Cathepsin B1, plasminogen activator, and collagenase activity were assessed in tissue cytosols using specific synthetic oligopeptides as substrates. The expression of H-ras and nm23-H1 was investigated by means of immunohistochemistry and in situ hybridization.

RESULTS

Our results showed that cathepsin B1 was the most consistently elevated proteinase, demonstrating a linear correlation with clinical staging. H-ras expression was found elevated in 40% of the cases. Nm23-H1 protein immunoreactivity was positive in 40% of the cases. No correlation was found among H-ras, cathepsin B1 activity, and survival rate. Among cases with high cysteine proteinase activity, a different clinical behavior depending on the expression of Nm23-H1 was observed. The cases with Nm23-H1 protein had a markedly better survival rate than those lacking this protein. In contrast, the absence of Nm23-H1 in association with high cathepsin B1 activity was a clear indicator of a poor prognosis.

CONCLUSIONS

These findings suggest a complex interaction between the proteolytic phenotype and the expression of H-ras and nm23-H1 genes in carcinoma of the cervix that influences the clinical behavior of the tumor.

Expression of nm23 in normal, hyperplastic and neoplastic endometrial tissues

This study evaluated the expression of nm23 in curettage specimens from 63 cases of normal, hyperplastic and neoplastic endometrial tissues by immunohistochemistry. The histological diagnoses were as follows: normal proliferative (N = 5) or secretory (N = 5), simple hyperplasia (N = 11), complex hyperplasia (N = 9), atypical hyperplasia (N = 8) and adenocarcinoma (N = 25), consisting of endometrioid adenocarcinoma (N = 15), clear cell (N = 7) and serous papillary adenocarcinoma (N = 3). There was no immunostaining for nm23 protein in the 10 cases of normal endometria and in the 28 cases of endometrial hyperplasia. In contrast, 52% of the adenocarcinomas displayed a cytoplasmic staining pattern which was moderate to strong. This difference was statistically significant (p < 0.0001, chi-square test). nm23 expression in curettage specimens had no predictive value for determining the FIGO stage in the hysterectomy specimens (p = 0.2709, chi-square test). No significant difference for nm23 immunoreactivity was found between the histologic subtypes of endometrial adenocarcinoma (endometrioid versus serous papillary and clear cell, p = 0.1413, chi-square test). In this study, there was no immunostaining of normal endometria or of endometrial hyperplasia (including atypical endometrial hyperplasia) to support the hypothesis that expression of the nm23 gene product is related to the development of endometrial adenocarcinoma. In contrast, nm23 expression was upregulated in many cases of endometrial adenocarcinomas irrespective of the histologic subtype.

Molecular biology of breast cancer metastasis. Genetic regulation of human breast carcinoma metastasis

The present is an overview of recent data that describes the genetic underpinnings of the suppression of cancer metastasis. Despite the explosion of new information about the genetics of cancer, only six human genes have thus far been shown to suppress metastasis functionally. Not all have been shown to be functional in breast carcinoma. Several additional genes inhibit various steps of the metastatic cascade, but do not necessarily block metastasis when tested using in vivo assays. The implications of this are discussed. Two recently discovered metastasis suppressor genes block proliferation of tumor cells at a secondary site, offering a new target for therapeutic intervention.

nm23-H1 protein immunoreactivity in intraepithelial neoplasia and invasive squamous cell carcinoma of the uterine cervix

Differences in the immunohistochemical expression of the 17 kDa protein encoded by the human nm23-H1 gene were studied in premalignant lesions and invasive squamous cell carcinoma (SCC) (N = 8) of the cervix using routine streptavidin-biotin immunohistochemistry and a polyclonal antibody to the nm23-H1 protein. The premalignant lesions were koilocytic atypia due to wart virus infection (N = 5), low-grade cervical intraepithelial neoplasia (CIN) (N = 7) and high-grade CIN (N = 7). The carcinomas were either moderately (N = 3) or poorly differentiated (N = 5). The non-neoplastic controls were normal squamous epithelium from cases with uterine prolapse (N = 7) and normal squamous epithelium not affected by the infective or neoplastic areas of some of the cases with wart virus infection (N = 2) and carcinoma (N = 2). Moderate to strong cytoplasmic and, occasionally, nuclear immunostaining for the nm23-H1 protein was seen in all cells above the basal layer of the normal squamous epithelium. However, most of the cervical SCC show a relative reduction in nm23-H1 immunoreactivity (7/8 cases; 88%). This difference in nm23-H1 expression was statistically significant (P = 0.0006; Chi-squared test with continuity correction). All of the cases with wart virus infection (N = 5; 100%) displayed moderately strong nm23-H1 immunostaining throughout the squamous epithelium except for the basal layer where no staining was observed. The cases that had low-grade squamous dysplasia of the cervix (CIN I-II) (N = 7; 100%) also displayed moderate to strong nm23-H1 immunoreactivity in the epithelium except for the basal layer (CIN I) or the lower two-thirds of the epithelium (CIN II). nm23-H1 Immunoreactivity was either absent or was significantly reduced in all of the high-grade CIN (CIN III) cases (N = 7; 100%) in which only the non-dysplastic superficial third of the squamous epithelium displayed nm23-H1 immunolabeling. The difference in nm23-H1 expression between low-grade and high-grade CIN cases was statistically significant (P = 0.0013; Chi-squared test with continuity correction). Similarly, the difference between low-grade CIN and SCC cases in the expression of nm23-H1 was also significant (P = 0.0041; Chi-squared test with continuity correction). However, no statistically significant difference in nm23-H1 immunoreactivity was found between cases of high-grade CIN and SCC. In conclusion, nm23-H1 protein immunoreactivity is reduced in high-grade CIN and cervical SCC but not in low-grade CIN. These findings suggest that reduced expression of the protein may be important early in the sequential development of cervical squamous neoplasia.

Nm23-H1 expression in intrahepatic or extrahepatic metastases of hepatocellular carcinoma

AIMS/BACKGROUND

Decreased expression of nm23, a putative metastasis suppressor gene, has been reported to be related to either intrahepatic metastasis or a poor prognosis in hepatocellular carcinoma (HCC). The aim of this study was to elucidate the true role of nm23-H1 expression in both intrahepatic and distant metastases of HCC.

METHODS

Thirteen patients with single-nodule HCC, seven patients with HCC having satellite nodules and seven patients with HCCs having extrahepatic metastases were included in this study. The expression of nm23-H1 protein was immunohistochemically examined in both primary and metastatic nodules.

RESULTS

Ten of 13 single-nodule HCCs were found to overexpress nm23-H1 protein. All main tumors, having satellite nodules, were found to overexpress nm23-H protein, except for two HCCs, which only partially expressed nm23-H1 protein. Regarding the nm23-H1 expression in intrahepatic metastases, most nodules overexpressed the protein. The expression of nm23-H1 was found to be low in only one intrahepatic metastasis specimen, while its primary tumor was also found to show a low expression of nm23-H1 protein. Microscopic portal vein invasion was found in three of the five patients studied, and all cancer cells in portal invasion overexpressed nm23-H1 protein. Nm23-H1 protein was expressed in all distant metastatic tumors and the staining intensity of most metastatic nodules was similar to that of the primary tumors.

CONCLUSIONS

Our study demonstrated that nm23-H1 expression did not always decrease but instead tended to increase at both intrahepatic and extrahepatic metastatic sites. Based on these findings, nm23-H1 expression is not considered to be a reliable indicator of either intrahepatic or distant metastasis in HCC.