Yingnan Yu

National University of Singapore, Singapore, Singapore

Are you Yingnan Yu?

Claim your profile

Publications (5)14.69 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: AimsY Box Binding Protein-1 (YB-1) is known to modulate gene transcription and protein translation, as well as cellular response to drug treatment. The aim of this study is to correlate YB-1 protein expression levels with clinicopathological parameters in the intestinal type of gastric cancer tissue samples (as categorized by the Lauren classification) and substantiate the findings with in vitro experimentation.Methods and resultParaffin-embedded samples from 167 patients with intestinal type of gastric cancer were used for the construction of tissue microarrays (TMAs). TMA slides were immunostained and YB-1 immunoreactivity was based on the weighted average intensity score. Univariate analysis revealed that YB-1 immunohistochemical expression was significantly correlated with lymph node status (P=0.054, borderline significance) and perforation (P=0.043). YB-1 expression was also found to be an independent predictor of lymph node spread by multivariate analysis. Furthermore, siRNA-mediated YB-1 gene knock down in MKN7 gastric cancer cells (which is known to originate from intestinal type of gastric cancer tissue) significantly inhibited cell migration (P=0.0002) and invasion in vitro (P=0.0129).ConclusionYB-1 expression is associated with lymph node spread in the intestinal type of gastric cancer and is a potential prognostic biomarker in this subtype of gastric cancer.This article is protected by copyright. All rights reserved.
    Histopathology 10/2014; · 2.86 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Breast cancer metastasis accounts for the majority of deaths from breast cancer. Detection of breast cancer metastasis at the earliest stage is important for the management and prediction of breast cancer progression. Emerging techniques using the analysis of circulating tumor cells show promising results in predicting and identifying the early stages of breast cancer metastasis in patients. Additionally, a deeper understanding of the metastatic cascade in breast cancer will be critical for developing therapeutic interventions to combat breast cancer metastasis. In this review, the current and novel methods for detection of breast cancer metastasis, as well as the mechanisms involved in metastasis and the treatment of breast cancer metastasis, are discussed.
    Cancer genomics & proteomics. 09/2012; 9(5):311-20.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: DZNep (3-deazaneplanocin A) depletes EZH2, a critical component of polycomb repressive complex 2 (PRC2), which is frequently deregulated in cancer. Despite exhibiting promising anticancer activity, the specific genetic determinants underlying DZNep responsiveness in cancer cells remain largely unknown. We sought to determine molecular factors influencing DZNep response in gastric cancer. Phenotypic effects of DZNep were evaluated in a panel of gastric cancer cell lines. Sensitive lines were molecularly interrogated to identify potential predictors of DZNep responsiveness. The functional importance of candidate predictors was evaluated using short hairpin RNA (shRNA) and siRNA technologies. DZNep depleted PRC2 pathway components in almost all gastric cancer lines, however, only a subset of lines exhibited growth inhibition upon treatment. TP53 genomic status was significantly associated with DZNep cellular responsiveness, with TP53 wild-type (WT) lines being more sensitive (P < 0.001). In TP53-WT lines, DZNep stabilized p53 by reducing ubiquitin conjugation through USP10 upregulation, resulting in activation of canonical p53 target genes. TP53 knockdown in TP53-WT lines attenuated DZNep sensitivity and p53 target activation, showing the functional importance of an intact p53 pathway in regulating DZNep cellular sensitivity. In primary human gastric cancers, EZH2 expression was negatively correlated with p53 pathway activation, suggesting that higher levels of EZH2 may repress p53 activity. Our results highlight an important role for TP53 genomic status in influencing DZNep response in gastric cancer. Clinical trials evaluating EZH2-targeting agents such as DZNep should consider stratifying patients with gastric cancer by their TP53 genomic status.
    Clinical Cancer Research 06/2012; 18(15):4201-12. · 7.84 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The Y-box binding protein 1 (YB-1), characterized by the presence of the cold shock domain, has been reported to induce chemoresistance in cancer therapy. Chemotherapy is one of the main therapeutic strategies in the treatment of cancer, in addition to surgery, radiation therapy, and hormonal therapy. However, chemoresistance remains a key obstacle to successful cancer management. In this review, we will focus on the role of YB-1, an important regulator of gene transcription, in cancer therapy and chemoresistance.
    The Anatomical Record Advances in Integrative Anatomy and Evolutionary Biology 12/2011; 295(2):215-22. · 1.34 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Peroxiredoxin III (Prx III), an antioxidant protein found in mitochondria, plays an essential role in mitochondrial homeostasis. Aberrant expression of Prx III has been implicated in the tumorigenesis of various cancers. In this study, we evaluated the expression of Prx III in breast cancer tissues and elucidated its role in cell proliferation, a hallmark of cancer. Breast tissue microarrays comprising 106 breast cancer sections were stained with Prx III antibody using immunohistochemisty and correlated with proliferating cell nuclear antigen (PCNA) immunostaining. To validate the role of Prx III in cell proliferation, expression of Prx III was analyzed at the mRNA and protein levels by real-time RT-PCR, Western blotting and immunofluorescence in vitro. siRNA mediated silencing of Prx III in MDA-MB-231 breast cancer cells was performed and the effect on the cell cycle was examined. Prx III expression in patient tissue microarray samples was found to be positively associated with PCNA immunostaining, a proliferative marker. Prx III was expressed in both MCF-7 and MDA-MB-231 breast cancer cell lines and transient transfection with siPrx III in MDA-MB-231 cells induced inhibition of cell proliferation and cell cycle arrest. The data suggests that Prx III has a significant role in cell cycle regulation and could be a potential proliferation marker in breast cancer.
    International Journal of Oncology 02/2010; 36(2):359-64. · 2.66 Impact Factor