A and B histo-blood group antigens are present on carcinoma cells at the early stages of cancerogenesis and tend to disappear at later stages, but it is not yet clear whether they take part to the process of tumor progression. To gain some insight into this issue, we used a rat colon carcinoma experimental model. To obtain expression of the A antigen, REG cells were cotransfected with the rat A enzyme cDNA and a rat alpha1,2fucosyltransferase cDNA, either FTA or FTB, whereas PRO cells that spontaneously have alpha1,2fucosyltransferase activity were only transfected with the A enzyme cDNA. All A antigen-expressing transfected cells derived from either REG FTA, REG FTB, or PRO parental cells were more resistant to apoptosis induced by either serum deprivation or heat shock than were their respective controls. When injected to syngeneic immunocompetent rats, A enzyme-transfected PRO cells formed tumors that grew faster than those formed by mock-transfected PRO cells. However, in immunodeficient SCID mice, no difference in growth could be observed between the two types of tumors, indicating that the faster tumor growth of the A antigen-positive cells in immunocompetent animals was due to their higher ability to escape immune control and that this was associated with their higher degree of resistance to apoptosis. These results might explain the slightly augmented incidence of carcinomas observed in A and B blood group individuals compared to O individuals.

中文翻译：

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组织血A组抗原的表达增加了对细胞凋亡的抵抗力，并促进了对大鼠结肠癌细胞免疫控制的逃逸。

A和B组织血型抗原在癌发生的早期阶段存在于癌细胞上，并在晚期阶段趋于消失，但尚不清楚它们是否参与肿瘤进展的过程。为了获得对该问题的一些了解，我们使用了大鼠结肠癌实验模型。为了获得A抗原的表达，将REG细胞与大鼠A酶cDNA和大鼠α1,2岩藻糖基转移酶cDNA（FTA或FTB）共转染，而自发具有α1,2岩藻糖基转移酶活性的PRO细胞仅被A酶cDNA转染。源自REG FTA，REG FTB或PRO亲本细胞的所有表达A抗原的转染细胞比其各自的对照对血清剥夺或热休克诱导的细胞凋亡更有抵抗力。当被注射到同基因免疫功能正常的大鼠中时，经酶转染的PRO细胞形成的肿瘤的生长速度快于由模拟转染的PRO细胞形成的肿瘤。但是，在免疫缺陷的SCID小鼠中，两种类型的肿瘤之间没有观察到生长差异，这表明免疫活性动物中A抗原阳性细胞的较快肿瘤生长是由于它们具有更高的逃避免疫控制的能力，并且这与它们对细胞凋亡的更高抗性有关。这些结果可能解释了与O个体相比，A和B血型个体中观察到的癌症发病率略有增加。在这两种类型的肿瘤之间没有观察到生长的差异，这表明免疫活性动物中A抗原阳性细胞的较快肿瘤生长是由于它们逃避免疫控制的能力更高，这与它们较高的免疫力程度有关。抗凋亡。这些结果可能解释了与O个体相比，A和B血型个体中观察到的癌症发病率略有增加。在这两种类型的肿瘤之间没有观察到生长的差异，这表明免疫活性动物中A抗原阳性细胞的较快肿瘤生长是由于它们逃避免疫控制的能力更高，这与它们较高的免疫力程度有关。抗凋亡。这些结果可能解释了与O个体相比，A和B血型个体中观察到的癌症发病率略有增加。