Basic study of tumor-vaccine for metastatic epithelial cancer.

利用KE4细胞毒性T细胞(CTL)细胞系，通过基因表达克隆的方法获得了一个LCK基因。KE4-CTL系以前是从鳞状细胞癌的肿瘤浸润性淋巴细胞(TIL)中建立的。Lck蛋白(p56k/c)是一种src家族酪氨酸激酶，对T细胞的发育和功能至关重要，在转移性结肠癌中异常表达。在癌细胞系中使用了与先前报道的结果一致的I型转录本，而在正常细胞和组织中使用了II型转录本。此外，所有p56；lck&gt；食道癌细胞系都是从有明显转移的原发食道癌患者中建立的，包括克隆了lck基因的KE4肿瘤细胞作为编码肿瘤排斥抗原的基因。P56^&lt；lck&gt；似乎通过启动锚定非依赖性增殖促进了上皮细胞的恶性转化。我们鉴定了三个可被KE4-CTL识别的多肽(Lck 208-216、Lck 486-494和Lck 488-497)。这些LCK多肽增强了结肠癌和其他有转移的上皮性肿瘤患者外周血单核细胞中Cth的活性，但不能增强无转移的患者的Cth活性。在转移性癌症患者新鲜制备的PBMC中发现了识别Lck多肽的CTL前体细胞，其频率在Lck多肽刺激下显著增加。因此，LCK多肽可用于转移性癌症患者的特异性免疫治疗。

A lck gene was identified by the gene-expression cloning method, in which a KE4-cytotoxic T cell (CTL) line was used. The KE4-CTL line was previously established from tumor-infiltrating lymphocytes (TILs) of squamous cell carcinoma. The Lck protein (p56k/c), a src family tyrosine kinase which is essential for T cell development and function, is aberrantly expressed in metastatic colon cancers. The type I transcript was used in the cancer cell lines, in agreement with the results reported previously, whereas the type II transcript was used in normal cells and tissues.Further, all p56^<lck> esophageal cancer cell lines were established from the primary esophageal tumors patients who had distinct metastases, including the KE4 tumor cells from which the lck gene was cloned as a gene encoding tumor-rejection antigen. p56^<lck> seems to facilitate the malignant transformation of epithelial cells through initiation of anchorage-independent proliferation. We identified three peptides (Lck208-216, Lck486-494, and Lck488-497), which were recognized by KE4-CTL. These Lck peptides augmented CTh activity in peripheral blood mononuclear cells of colon and other epithelial cancer patients with metastasis, but not those without metastasis. CTL precursors recognizing the Lck peptide were identified in freshly prepared PBMCs of metastatic cancer patients, and their frequency was significantly augmented by the stimulation with the peptide. Thus, Lck peptides could be useful for specific immunotherapy toward metastatic cancer patients.