Expression of KK-LC-1, a cancer/testis antigen, at non-tumour sites of the stomach carrying a tumour

Abstract

Kita-Kyushu lung cancer antigen-1 (KK-LC-1) is a cancer/testis antigen (CTA) and predominant target for cancer immunotherapy. Our previous study indicated that KK-LC-1 was expressed in 82% of gastric cancers, and also in 79% of early stage of gastric cancers, with a correlation to Helicobacter pylori (H. pylori) infection. In addition, we found that KK-LC-1 was occasionally expressed at non-tumour sites of stomachs carrying tumours. Here, we investigated the characteristics of KK-LC-1 expression at non-tumour sites and the clinical utility of these phenomena. The gene expression of KK-LC-1 was detected at the non-tumour sites including pyloric glands. The most detectable corpus/gland subset had a KK-LC-1 expression rate of 77% in the pyloric gland of the lower corpus where H. pylori preferentially exists. KK-LC-1 expression rates were 67% or 32% with or without intestinal metaplasia, which also induced by H. pylori, respectively. Consequently, KK-LC-1 would be detected at the pre-cancerous condition of the stomach, and may be a useful marker to predict gastric cancer.

Hypomethylation‐mediated activation of cancer/testis antigen KK‐LC‐1 facilitates hepatocellular carcinoma progression through activating the Notch1/Hes1 signalling

“…6 The expression rate of KK-LC-1 in human malignancies is markedly higher than the rates of other CT antigens. 9 KK-LC-1 is cancer cell selective and immunogenic, and expressed at high level and frequency in cancers, 6 making it an ideal cancer immunotherapy target. 9 KK-LC-1 is cancer cell selective and immunogenic, and expressed at high level and frequency in cancers, 6 making it an ideal cancer immunotherapy target.…”

KK-LC-1 may be an effective prognostic biomarker for gastric cancer

“…In the present study, we found that the overall expression of KK-LC-1 in tumor tissues was signi cantly higher than that in normal tissues, and GC patients with higher KK-LC-1 expression had a better prognosis. Fukuyama et al [29] also found similar results that KK-LC-1 gene expression was higher in tumor regions than in non-tumor regions, and KK-LC-1 was occasionally expressed at non-tumour sites of stomachs carrying tumours. In our experimental results, the expression rate of KK-LC-1 in tumor tissues was 95.7%.…”

Detection of Kita-Kyushu Lung Cancer Antigen-1, a Cancer/testis Antigen, in the stomach closer to the cancerous condition.

“…Such an issue may be resolved by sampling multiple mucosa sites from the lower corpus. Supplementary Figure S1 and results from our previous study show that KK-LC-1's expression rate in the lower corpus was of 68.1 and 66.1%, respectively [16].…”

“…Furthermore, in an earlier study, Fukuyama et al clari ed the speci c phenomena at the basis of the correlation between KK-LC-1 expression and Hp infection. Additionally, we previously showed how KK-LC-1 expression was frequently detected at non-tumour sites of the stomach occurring GC [14,16]. However, from these studies, it remained unclear whether KK-LC-1 was expressed in the stomach of patients who were not carrying a tumour and with Hp infection.…”

“…Such ndings indicate that KK-LC-1 expression occurs at the beginning of a malignancy and is subsequently maintained. Furthermore, our group has observed that KK-LC-1 is expressed in the premalignant lesions of the stomach [16]. However, to date, it remains to be clari ed whether the non-premalignant stomach expresses KK-LC-1.…”