Ohni Sumie, Yamaguchi Hiromi, Hirotani Yukari, Nakanishi Yoko, Midorikawa Yutaka, Sugitani Masahiko, Nakayama Tomohiro, Makishima Makoto, Esumi Mariko
Division of Oncologic Pathology, Department of Pathology and Microbiology, Nihon University School of Medicine Tokyo, Japan.
Division of Biochemistry, Department of Biomedical Sciences, Nihon University School of Medicine Tokyo, Japan.
Am J Transl Res. 2024 Feb 25;16(2):690-699. doi: 10.62347/CQJW7490. eCollection 2024.
To clarify the mechanism underlying the development and poor prognosis of combined hepatocellular-cholangiocarcinoma (cHCC-CCA), we characterized liver cancer driver mutations and poor prognostic markers in both the HCC and intrahepatic CCA (iCCA) components of a cHCC-CCA tumor. The telomerase reverse transcriptase () promoter mutation C228T was quantified by digital polymerase chain reaction using DNA from multiple microdissected cancer components of a single cHCC-CCA nodule. The protein expression of cancer-related markers, including TERT, was examined by serial thin-section immunohistochemistry and double-staining immunofluorescence. promoter mutation and TERT protein expression were detected in all cancer components but not in noncancer regions. promoter mutation frequencies were similar among components; those of TERT protein-positive cancer cells were higher in iCCA and mixed components than in HCC. The frequencies of Ki67- and p53-positive cells were similarly higher in iCCA and mixed components than in HCC. However, double-positive cells for the three proteins were unexpectedly rare; single-positive cells dominated, indicating phenotypic microheterogeneity in cancer cells within a component. Interestingly, HCC and CCA marker protein immunohistochemistry suggested dedifferentiation of HCC and transdifferentiation from HCC to iCCA in HCC and iCCA components, respectively. Such phenotypic intercomponent heterogeneity and intracomponent microheterogeneity were detected in a tumor nodule of cHCC-CCA uniformly carrying the early HCC driver mutation. Moreover, poor prognostic markers were randomly expressed without a regular pattern, consistent with the poor prognosis.
为了阐明肝细胞-胆管癌（cHCC-CCA）发生发展及预后不良的潜在机制，我们对cHCC-CCA肿瘤的肝癌和肝内胆管癌（iCCA）成分中的肝癌驱动突变和预后不良标志物进行了特征分析。采用数字聚合酶链反应，利用来自单个cHCC-CCA结节多个显微切割癌组织成分的DNA，对端粒酶逆转录酶（TERT）启动子突变C228T进行定量分析。通过连续薄切片免疫组织化学和双染免疫荧光法检测包括TERT在内的癌症相关标志物的蛋白表达。TERT启动子突变和TERT蛋白表达在所有癌组织成分中均有检测到，但在非癌区域未检测到。各成分间TERT启动子突变频率相似；iCCA和混合成分中TERT蛋白阳性癌细胞的频率高于肝癌。Ki67和p53阳性细胞的频率在iCCA和混合成分中同样高于肝癌。然而，三种蛋白双阳性的细胞出乎意料地罕见；单阳性细胞占主导，表明成分内癌细胞存在表型微异质性。有趣的是，肝癌和胆管癌标志物蛋白免疫组织化学分别提示肝癌成分中肝癌的去分化以及肝癌和iCCA成分中从肝癌向iCCA的转分化。在一个均匀携带早期肝癌驱动突变的cHCC-CCA肿瘤结节中检测到了这种成分间表型异质性和成分内微异质性。此外，预后不良标志物呈随机表达，无规律模式，这与预后不良一致。
