Shan Lu

California Pacific Medical Center Research Institute, San Francisco, California, United States

Are you Shan Lu?

Claim your profile

Publications (2)5.6 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Most polymerase chain reaction (PCR) systems employ pre-determined settings and proprietary master mixes that differ from one system to another. It is not known whether these differences may affect gene expression values. We compared two major real-time PCR technologies, from Life Technologies (formerly Applied Biosystems; ABI7500) and Roche Applied Science (LC480), using their default settings, proprietary reagents and other potential variables such as ramp rates and magnesium concentrations. We analyzed four genes (IL-8, COX2, ID-1 and CXCR2) in a human breast cancer cell line and found that two of them, though readily detected by ABI, were not detected using the Roche system. By altering some of the parameters and reagents used in the Roche protocol, we were able to detect expression of these two genes, but the level remained far below that detected by ABI, particularly for ID-1. When we tested three additional ID-1 primer pairs, two of these primer pairs yielded higher expression values in the LC system, yet still significantly lower than the values obtained in ABI. These results suggest critical differences in these two PCR systems, which could result in significant discrepancies in results reported by different laboratories.
    No preview · Article · Apr 2010 · Molecular and Cellular Probes
  • [Show abstract] [Hide abstract]
    ABSTRACT: We previously reported that gene expression analysis of biopsies of normal-appearing large intestinal mucosa can distinguish individuals with colonic cancer and many individuals at risk for colon cancer from controls. The purpose of this study was to determine whether noninvasively removed rectal swabs can identify individuals with colon cancer or risk of colon cancer as effectively as we previously demonstrated using biopsies. Rectal mucosa cells were removed by rectal swabs, and their gene expression profiles were compared with those of biopsies removed by colonoscopy. Expression of 16 genes in the rectal mucosa of 12 individuals with colon cancer, 25 with polyps, 37 with family or self-reported cancer history, and 23 controls was measured by real-time reverse transcription-polymerase chain reaction. We found similar results using rectal swabs and biopsies. Groups of individuals with or at risk for cancer showed an altered gene expression profile compared with controls. Moreover, each of the 12 cancer patients showed altered expression relative to the mean of controls. Gene expression analysis using rectal swabs may provide a convenient way to screen for colon cancer.
    No preview · Article · May 2009 · Diseases of the Colon & Rectum

Publication Stats

7 Citations
5.60 Total Impact Points


  • 2009-2010
    • California Pacific Medical Center Research Institute
      San Francisco, California, United States