肝癌（Hepatocellular carcinoma，HCC）在亞洲是一種非常普遍的癌症，而且在台灣地區的死亡率則是高居榜首。本實驗在最近的研究顯示肝癌的細胞膜中PKC的活性比正常肝細胞的細胞膜中PKC的活性低，且隨著肝癌組織的惡化其活性會隨之降低，此種現象與腫瘤大小及癌化的程度有關。本實驗想要確定PKC異構物在肝癌中扮演的角色。因此利用RT-PCR的技術來探討肝癌組織中PKC異構物和細胞增殖指標mRNA的表現。首先萃取43組肝癌組織及肝細胞癌鄰近正常組織的mRNA，然後採用RT-PCR技術來偵測PKC異構物和細胞增殖指標在肝癌組織的表現量，同時以DNA定序儀定序確定其專一性。結果發現肝癌組織內PKCαmRNA表現量比肝癌鄰近正常組織的表現量有明顯的增加，表示肝癌組織內PKCα正處在活化的狀態。此外肝癌組織內CPKCδ、PKCε、PKCμ 及PKCζ mRNA表現量增加。另外PKC下游基因（C-raf-1、MEK、MAPK）的蛋白表現量和細胞增殖指標（Cdc2、PCNA及cyclin D1）mRNA的表現量增加 ，因此證明PKC異構物mRNA的過度表現（overexpression）可能參與在肝癌形成的過程。
Human hepatocellular carcinoma（HCC） is one of the most common cancers in Asia﹒Our recent data had also showed that the decreased levels of membrane-bound PKC activity and PKCα protein in HCC were correlated with tumor stage and tumor size﹒To verify the role of PKC in HCC﹐this study was further determined the mRNA level of PKC isoforms and cell proliferation markers in HCC by use RT-PCR﹒The total mRNA was isolated from the surgical specimens of 43 patients of HCC and adjacent normal tissues﹒The product of RT-PCR was also checked by DNA sequence analysis﹒The result showed that the level PKCα mRNA in the cancer tissue were significantly higher than that in the adjacent normal tissue﹐specifying that the alteraions in the PKCα may signify their activation in liver cancer﹒Inaddition﹐the level of PKCδ、PKCε、PKCμ and PKCζ mRNA in the cancer tissue were also significantly higher than that in the adjacent normal tissue﹒Moreover﹐the protein expressions of the PKC down-stream gene（c-raf、MEK、MAPK）and the mRNA expression of the cell proliferation markers were also increased in cancer tissues. Thus , we suggested that the over-expression of PKC isoforms may be involved in the malignant progression of HCC.
