Komada F, Nishikawa M, Uemura Y, Morita K, Hidaka H, Shirakawa S
Department of Internal Medicine, Mie University School of Medicine, Japan.
Cancer Res. 1991 Aug 15;51(16):4271-8.
We examined the levels of protein kinase C (PKC) activity and the expressions of its three major isozymes, designated types I (gamma), II (beta), and III (alpha), in the cytosol and particulate fractions of cells from patients with acute myelogenous leukemia (AML), acute lymphocytic leukemia (ALL), and chronic lymphocytic leukemia (CLL), in an attempt to elucidate the cell type- or lineage-specific expression of these isozymes. The levels of PKC activities in the cytosol and particulate fractions from AML cells were higher than those from ALL or CLL cells. The average PKC activities of AML cells, ALL cells, and CLL cells were 18.7, 12.2, and 11.3 pmol/min/10(8) cells, respectively, in the cytosol fractions and 4.4, 3.1, and 2.6 pmol/min/10(8) cells, respectively, in their particulate fractions. M1 cells (French-American-British classification) and AML cells with T-lymphocyte-associated surface antigens, such as CD2 and CD7, had significantly lower PKC activities among AML cells. Immunoblot analyses using monoclonal antibodies against each isozyme revealed that all three isozymes were broadly distributed on leukemic cells with considerable variability in the level of expression. All lymphoid leukemic cells expressed PKC-gamma in the cytosol fractions, albeit a minor component; however, this type was observed in cells from only half the number of AML patients. Those AML cells with cytosolic PKC-gamma usually expressed lymphoid surface antigens, such as CD2, CD7, and CD19. On the other hand, cytosolic PKC-beta and PKC-alpha were commonly observed in all types of leukemic cells. AML cells expressed these two types at almost equal levels, but in lymphoid cells, expressions of PKC-beta were usually more abundant than those of PKC-alpha. These data suggest that AML cells with lymphoid antigens might have a lower PKC activity but more predominant expression of cytosolic PKC-gamma than the usual AML cells.
我们检测了急性髓性白血病（AML）、急性淋巴细胞白血病（ALL）和慢性淋巴细胞白血病（CLL）患者细胞的胞浆和颗粒部分中蛋白激酶C（PKC）的活性水平及其三种主要同工酶（分别命名为I型（γ）、II型（β）和III型（α））的表达，以试图阐明这些同工酶在细胞类型或谱系中的特异性表达。AML细胞胞浆和颗粒部分的PKC活性水平高于ALL或CLL细胞。在胞浆部分，AML细胞、ALL细胞和CLL细胞的平均PKC活性分别为18.7、12.2和11.3 pmol/分钟/10⁸个细胞，在其颗粒部分分别为4.4、3.1和2.6 pmol/分钟/10⁸个细胞。M1细胞（法美英分类）和具有T淋巴细胞相关表面抗原（如CD2和CD7）的AML细胞在AML细胞中PKC活性显著较低。使用针对每种同工酶的单克隆抗体进行免疫印迹分析表明，所有三种同工酶在白血病细胞中广泛分布，表达水平存在相当大的差异。所有淋巴样白血病细胞在胞浆部分均表达PKC-γ，尽管含量较少；然而，仅在一半数量的AML患者细胞中观察到这种类型。那些具有胞浆PKC-γ的AML细胞通常表达淋巴样表面抗原，如CD2、CD7和CD19。另一方面，胞浆PKC-β和PKC-α在所有类型的白血病细胞中普遍存在。AML细胞中这两种类型的表达水平几乎相等，但在淋巴样细胞中，PKC-β的表达通常比PKC-α更丰富。这些数据表明，具有淋巴样抗原的AML细胞可能比普通AML细胞具有更低 的PKC活性，但胞浆PKC-γ的表达更占优势。
