We performed a genome-wide association study of esophageal squamous cell carcinoma (ESCC) by genotyping 1,077 individuals with ESCC and 1,733 control subjects of Chinese Han descent. We selected 18 promising SNPs for replication in an additional 7,673 cases of ESCC and 11,013 control subjects of Chinese Han descent and 303 cases of ESCC and 537 control subjects of Chinese Uygur-Kazakh descent. We identified two previously unknown susceptibility loci for ESCC: PLCE1 at 10q23 (P(Han combined for ESCC) = 7.46 x 10(-56), odds ratio (OR) = 1.43; P(Uygur-Kazakh for ESCC) = 5.70 x 10(-4), OR = 1.53) and C20orf54 at 20p13 (P(Han combined for ESCC) = 1.21 x 10(-11), OR = 0.86; P(Uygur-Kazakh for ESCC) = 7.88 x 10(-3), OR = 0.66). We also confirmed association in 2,766 cases of gastric cardia adenocarcinoma cases and the same 11,013 control subjects (PLCE1, P(Han for GCA) = 1.74 x 10(-39), OR = 1.55 and C20orf54, P(Han for GCA) = 3.02 x 10(-3), OR = 0.91). PLCE1 and C20orf54 have important biological implications for both ESCC and GCA. PLCE1 might regulate cell growth, differentiation, apoptosis and angiogenesis. C20orf54 is responsible for transporting riboflavin, and deficiency of riboflavin has been documented as a risk factor for ESCC and GCA.

The aim of this study was to evaluate the diagnostic values by detecting sera autoantibodies to eight tumor-associated antigens (TAAs) of P53, IMP1, P16, cyclin B1, P62, C-myc, Survivn and Koc full-length recombinant proteins for the screening of high-risk subjects and early detection of esophageal squamous cell carcinoma (ESCC). Enzyme-linked immunosorbent assay was used to detect autoantibodies against the eight selected TAAs in 567 sera samples from four groups, including 200 individuals with normal esophageal epithelia (NOR), 214 patients with esophageal basal cell hyperplasia (BCH), 65 patients with esophageal dysplasia (DYS), and 88 patients with ESCC. In addition, the expression of the eight antigens in esophageal tissues was analyzed by immunohistochemistry. Statistically significant distribution differences were identified among the four groups for each of the individual autoantibodies to six TAAs (P53, IMP1, P16, cyclin B1, P62, and C-myc); the detection rates of antoantibodies were positively correlated with the progression of ESCC. When autoantibody assay successively accumulated to six TAAs (P53, IMP1, P16, cyclin B1, P62, and C-myc), a stepwise increased detection frequency of autoantibodies was found in the four sera groups (6% in NOR, 18% in BCH, 38% in DYS, and 64% in ESCC, respectively), the risks to BHC, DYS, and ESCC steadily increased about 3-, 9-, and 27-folds. The sensitivity and the specificity for autoantibodies against the six TAAs in diagnosing ESCC reached up to 64% and 94%, respectively. The area under the receiver operating characteristic curve for the six anti-TAA autoantibodies was 0.78 (95% confidence interval 0.74-0.83). No more increasing in sensitivity was found with the addition of new anti-TAA autoantibodies. A combination detection of autoantibodies to TAAs might distinguish ESCC patients from normal individuals and the patients with esophageal precancerous lesions.

To evaluate the diagnostic values of using autoantibodies in sera to a panel of eight tumor-associated antigens (TAAs) of P53, Koc, P62, C-myc, IMP1, Survivn, P16 and Cyclin B1 full-length recombinant proteins for early detection of patients with gastric cardia adenocarcinoma (GCA) and high-risk subjects screening. Enzyme-linked immunosorbent assay was used to detect autoantibodies against the eight selected TAAs in 383 sera samples from four groups, including 140 subjects with normal gastric cardia epithelia (NOR), 76 patients with chronic atrophic gastritis (CAG), 79 patients with gastric cardia dysplasia (DYS) and 88 patients with GCA. In addition, the expression of the eight antigens was analyzed in gastric cardia tissues by immunohistochemical method. The individual autoantibodies to six TAAs (P53, P62, IMP1, Survivn P16 and Cyclin B1) were significantly higher in sera from patients with GCA than that in normal subjects (P < 0.05). When autoantibody assay successively accumulated to seven TAAs (P53, Koc, P62, C-myc, IMP1, Survivn and P16), a stepwise increased detection frequency of autoantibodies was found in the four sera groups (13% in NOR, 39% in CAG, 46% in DYS, and 64% in GCA, respectively), the risks to CAG, DYS and GCA steadily increased about 4.4-, 5.7- and 12.0-fold. The sensitivity and the specificity for autoantibodies against the seven TAAs in diagnosing GCA reached up to 64% and 87%, respectively. The area under the receiver operating characteristic curve for the seven anti-TAA autoantibodies was 0.73 (95%CI: 0.68-0.78) No more increase in sensitivity was found with the addition of new anti-TAA autoantibodies. A combination detection of autoantibodies to TAAs might be helpful to distinguish GCA patients from normal subjects and the patients with gastric cardia precancerous lesions. In addition, further studies in patients with GCA and precancerous lesions using enlarged TAA panels might improve the sensitivity and specificity of cancer detection and high-risk subjects screening.