Neuroblastoma and Active Oxygen ; Role in Tumor Outgrowth and Malignancy

神经母细胞瘤（NB）是儿童时期最常见的实体恶性肿瘤，偶尔也会发生在年幼的婴儿身上。宿主免疫被认为与这一现象有关。本研究利用可移植的C1300小鼠NB细胞系，探讨了活性氧与荷瘤宿主肿瘤生长的关系。将细胞（lx105）分别接种于新生A/J小鼠（出生后2周内）和成年小鼠（8周龄）。分别于肿瘤细胞接种后1、2、3、4周处死。测定肿瘤组织的电子自旋共振（ESR）谱、组织超氧化物歧化酶（SOD）活性、脂质过氧化氢（LPO）和一氧化氮（N0_2/N0_3）含量。测定细胞周期，并分析结果与SOD活性的关系。接种后2周的ESR光谱信号高于其他周。1组SOD活性低于2组，各周差异不显著。2组SOD活性在1 ~ 2周时升高，在3周时降低。第1组LPO各组间无明显变化，NO在第3 ~ 4周升高。2组LPO在3周时升高，NO在1周时最高，在2周时降低。上述结果提示，1组与2组一氧化氮的功能存在差异。

The spontaneous regression of neuroblastorna (NB) , the most common solid malignant tumor in chilhood, is occasionally encountered in younger infants. Host immunity is considered to be related to this phenomenon. The present study was conducted to examine the relationship between active oxygen and the tumor outgrowth in tumor bearing hosts using transplantable C1300 murine NB cell line. The cells (lx 105) were inoculated into newborn A/J mice (within 2 weeks after birth ; group 1) and into adult mice (8 weeks old ; group 2). The animals were sacrificed 1,2,3 and 4 weeks after tumor cell inoculation. The electron spin resonance (ESR) spectra, tissue superoxide dismutase (SOD) activity, lipid hydropeoxide (LPO) and NO (N0_2/N0_3) were measured in the tumor. The cell cycle were also measured, and the results analyzed in relation to SOD activity. The signal of ESR spectra was higher at 2 weeks after inoculation than at the other weeks. SOD activity in the' group 1 was lower than in the group 2, and there were no significant differences week by week. SOD activity in group 2 increased at 1 - 2 weeks, and decreased at 3 weeks. In group 1, LPO didnot varied among weeks, and NO increased at 3 - 4 weeks. In group 2, LPO increased at 3 weeks, and NO was highest at 1 week and decrased at 2 week. These results suggest that there is the difference in the function of NO between group 1 and group 2.