title: Down-regulated SPARCL1 is associated with clinical significance in human gastric cancer.
abstract: BACKGROUND
  SPARC-like protein 1 (SPARCL1), a member of extracelluar matrix glycoprotein, is involved in many physiological functions.
  
  
  METHODS
  Tissue microarray (TMA) blocks were constructed based on 1,072 Chinese patients, containing both gastric cancer (GC) tissues and adjacent normal mucosa tissues. We analyzed the expression of SPARCL1 from both mRNA and protein level, using Real-time quantitative polymerase chain reaction (qRT-PCR), semi-quantitative PCR, immunohistochemistry (IHC), and Western blotting. Loss of heterozygosity analysis at the SPARCL1 gene locus was carried out using ten paired tumor and matched normal tissues.
  
  
  RESULTS
  SPARCL1 mRNA was significantly reduced in tumor specimens compared with normal tissues. Down-regulation of SPARCL1 protein was detected in 413 cases (38.7%) of 1,072 primary gastric tumor tissues. Kaplan-Meier survival curves demonstrated that SPARCL1-positive patients had better median survival time than SPARCL1-negative patients (59 months vs. 28 months, P = 0.001). Multivariate survival analysis revealed that SPARCL1 was an independent prognostic factor in gastric adenocarcinoma patients with no metastasis and well/moderately differentiated. The incidence of LOH for each individual marker was 12.5% (1/8) for D4S2462, 20% (2/10) for D4S2929, and 33.3% (3/9) for SPARCL1.
  
  
  CONCLUSIONS
  Our study revealed the clinical significance of SPARCL1 expression, providing a basis that the loss of SPARCL1 is a negative event in GC progression and prognosis. Furthermore, SPARCL1 protein might be considered to be a potential differentiation marker.
authors.affiliation: Department of Medical Oncology, Changzheng Hospital, Shanghai, People's Republic of China.
authors.forename: Ping
authors.initials: P
authors.lastname: Li
authors.forename: Jianxin
authors.initials: J
authors.lastname: Qian
authors.forename: Guanzhen
authors.initials: G
authors.lastname: Yu
authors.forename: Ying
authors.initials: Y
authors.lastname: Chen
authors.forename: Ke
authors.initials: K
authors.lastname: Liu
authors.forename: Jie
authors.initials: J
authors.lastname: Li
authors.forename: Jiejun
authors.initials: J
authors.lastname: Wang
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism* / Q000401:mortality; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism*; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D018279:Carcinoma, Signet Ring Cell / Q000235:genetics / Q000378:metabolism* / Q000401:mortality; D016022:Case-Control Studies; D015536:Down-Regulation; D016326:Extracellular Matrix Proteins / Q000235:genetics / Q000378:metabolism*; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism*; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013270:Stomach / Q000473:pathology; D013274:Stomach Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000401:mortality; D015996:Survival Rate; D046888:Tissue Array Analysis
chemical_list: D014408:Biomarkers, Tumor; D002135:Calcium-Binding Proteins; D016326:Extracellular Matrix Proteins; D012333:RNA, Messenger; C503126:SPARCL1 protein, human