ONCOmmunity

Detection of KK-LC-1 Protein, a Cancer/Testis Antigen, in Patients with Breast Cancer.

By: Yasushi Kondo, Takashi Fukuyama, Rui Yamamura, Nobue Futawatari, Yoshinobu Ichiki, Yoichi Tanaka, Yatsushi Nishi, Yoshihito Takahashi, Hitoshi Yamazaki, Noritada Kobayashi, Masahiko Watanabe

Department of Surgery, School of Medicine, Kitasato University, Sagamihara, Japan.
2018-08-28; doi: 10.21873/anticanres.12937

Abstract

Background

Kita-Kyushu lung cancer antigen-1 (KK-LC-1) is a cancer/testis antigen and predominant target for cancer immunotherapy. Its detection is only established based on gene expression. In this study, we established a monoclonal antibody against KK-LC-1 to detect its protein expression in formalin-fixed samples.

Materials

The monoclonal antibody against KK-LC-1 was evaluated and the detection of KK-LC-1 between gene expression and protein expression was compared in patients with breast cancer. The monoclonal antibody clone 34B3, which we established, stained testicular germ cells positively.

Results

The rates of detection of KK-LC-1 gene and protein expression were 11.8% and 52.9%, respectively. Protein expression was detected in all triple-negative breast cancer cases studied (n=8). Furthermore, KK-LC-1 was detected in all tumours without oestrogen receptor expression.

Conclusion

This study indicated that KK-LC-1 expression was detected in breast cancer, especially in oestrogen receptor-negative subtypes.