Sialyltransferase STX (ST8SiaII): A novel molecular marker of metastatic neuroblastoma

Department of Pediatrics, Memorial Sloan-Kettering Cancer Center, New York, NY, USA.
International Journal of Cancer (Impact Factor: 5.09). 07/2006; 119(1):152-6. DOI: 10.1002/ijc.21789
Source: PubMed


Polysialic acid (PSA) is highly expressed in many human cancers, including neuroblastoma (NB), and is critical for cellular adhesion, neuronal migration and tumor metastasis. The key enzyme responsible for PSA synthesis is sialyltransferase STX (ST8SiaII). Using quantitative RT-PCR we (i) studied STX expression in 39 NB tumors and 8 cell lines and (ii) examined its potential clinical utility as an early response marker in the bone marrows of the entire cohort of 136 high-risk NB patients treated with an immunotherapy protocol utilizing anti-GD2 antibody 3F8 and GM-CSF. Based on the quantitation of 24 normal marrow and peripheral blood samples, a normalized STX transcript value below the mean + 2SD was defined as negative. Sensitivity of this assay was 1 NB cell in 10(6) normal mononuclear cells. STX expression was high among NB tumors of all stages, as well as NB cell lines of different phenotypes. Evaluation for early (2.5 months from protocol entry) marrow response by univariate Cox model indicated that STX marker status (positive versus negative) was strongly associated with both progression-free and overall survival (p < 0.0005 for both). Similarly, the STX transcript level of posttreatment marrows was also highly prognostic of outcome (PFS, p = 0.001; OS, p < 0.0005). We conclude that STX mRNA has potential clinical utility as a molecular marker of metastatic NB.

Full-text preview

Available from:
  • Source
    • "Therefore, research for novel specific markers is warranted and investigators are working in this direction. Cheung et al. hypothesize that sialyltransferase STX (ST8SiaII), the key enzyme for PSA synthesis, can potentially be a sensitive marker for metastatic NB (93). As stated above, PSA is critical for cellular adhesion, neuronal migration, and tumor metastasis, and it is highly expressed in many human cancers, including NB. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Neuroblastoma (NB), accounting for 10% of childhood cancers, exhibits aberrant cell-surface glycosylation patterns. There is evidence that changes in glycolipids and protein glycosylation pathways are associated to NB biological behavior. Polysialic acid (PSA) interferes with cellular adhesion, and correlates with NB progression and poor prognosis, as well as the expression of sialyltransferase STX, the key enzyme responsible for PSA synthesis. Galectin-1 and gangliosides, overexpressed and actively shedded by tumor cells, can modulate normal cells present in the tumor microenvironment, favoring angiogenesis and immunological escape. Different glycosyltransferases are emerging as tumor markers and potential molecular targets. Immunotherapy targeting disialoganglioside GD2 rises as an important treatment option. One anti-GD2 antibody (ch14.18), combined with IL-2 and GM-CSF, significantly improves survival for high-risk NB patients. This review summarizes our current knowledge on NB glycobiology, highlighting the molecular basis by which carbohydrates and protein-carbohydrate interactions impact on biological behavior and patient clinical outcome.
    Full-text · Article · Jul 2014 · Frontiers in Oncology
  • Source
    • "ST8SiaII gene expression has been shown to dramatically increase during tumour cell progression, whereas ST8SiaIV levels remain very low [54]. ST8SiaII has also been observed to regulate polySia expression in SCLC cells [55], and gene expression of ST8SiaII in neuroblastoma samples strongly correlates with stage and grade of disease and is highly prognostic of poor patient outcome [56,57]. . Additionally, oncogenic transcription factor Pax3 is closely involved in the regulation of ST8SiaII in tumour cells: engineered over-expression of this gene is known to increase ST8SiaII mRNA levels by up to four-fold, whereas ST8SiaIV mRNA is not affected [58]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Polysialic acid (polySia), an α-2,8-glycosidically linked polymer of sialic acid, is a developmentally regulated post-translational modification predominantly found on NCAM (neuronal cell adhesion molecule). Whilst high levels are expressed during development, peripheral adult organs do not express polySia-NCAM. However, tumours of neural crest-origin re-express polySia-NCAM: its occurrence correlates with aggressive and invasive disease and poor clinical prognosis in different cancer types, notably including small cell lung cancer (SCLC), pancreatic cancer and neuroblastoma. In neuronal development, polySia-NCAM biosynthesis is catalysed by two polysialyltransferases, ST8SiaII and ST8SiaIV, but it is ST8SiaII that is the prominent enzyme in tumours. The aim of this study was to determine the effect of ST8SiaII inhibition by a small molecule on tumour cell migration, utilising cytidine monophosphate (CMP) as a tool compound. Using immunoblotting we showed that CMP reduced ST8iaII-mediated polysialylation of NCAM. Utilizing a novel HPLC-based assay to quantify polysialylation of a fluorescent acceptor (DMB-DP3), we demonstrated that CMP is a competitive inhibitor of ST8SiaII (K i = 10 µM). Importantly, we have shown that CMP causes a concentration-dependent reduction in tumour cell-surface polySia expression, with an absence of toxicity. When ST8SiaII-expressing tumour cells (SH-SY5Y and C6-STX) were evaluated in 2D cell migration assays, ST8SiaII inhibition led to significant reductions in migration, while CMP had no effect on cells not expressing ST8SiaII (DLD-1 and C6-WT). The study demonstrates for the first time that a polysialyltransferase inhibitor can modulate migration in ST8SiaII-expressing tumour cells. We conclude that ST8SiaII can be considered a druggable target with the potential for interfering with a critical mechanism in tumour cell dissemination in metastatic cancers.
    Full-text · Article · Aug 2013 · PLoS ONE
  • Source
    • "Age, which is an important prognostic factor [2], does not seem to associate with the expression of these antigens. It has been suggested that immunohistochemically NCAM-negative NSCLC samples showing polySia expression, carry polySia on other molecules than NCAM [16,19]. On the basis of our results, NCAM appears to be the only carrier of polySia in neuroblastomas. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The expression of a neural crest stem cell marker, polysialic acid (polySia), and its main carrier, neural cell adhesion molecule (NCAM), have been detected in some malignant tumors with high metastatic activity and unfavorable prognosis, but the diagnostic and prognostic value of polySia-NCAM in neuroblastoma is unclear. A tumor tissue microarray (TMA) of 36 paraffin-embedded neuroblastoma samples was utilized to detect polySia-NCAM expression with a polySia-binding fluorescent fusion protein, and polySia-NCAM expression was compared with clinical stage, age, MYCN amplification status, histology (INPC), and proliferation index (PI). PolySia-NCAM-positive neuroblastoma patients had more often metastases at diagnosis, and polySia-NCAM expression associated with advanced disease (P = 0.047). Most interestingly, absence of polySia-NCAM-expressing tumor cells in TMA samples, however, was a strong unfavorable prognostic factor for overall survival in advanced disease (P = 0.0004), especially when MYCN was not amplified. PolySia-NCAM-expressing bone marrow metastases were easily detected in smears, aspirates and biopsies. PolySia-NCAM appears to be a new clinically significant molecular marker in neuroblastoma, hopefully with additional value in neuroblastoma risk stratification.
    Full-text · Article · Mar 2009 · BMC Cancer
Show more