Fujita S
Gan To Kagaku Ryoho. 1983 Feb;10(2 Pt 2):459-70.
The most remarkable changes of human stomach, closely related to carcinogenesis are intestinal metaplasia. In order to define an interrelation between these mucosal changes and carcinogenesis, it seems to be necessary to study structural dynamics of normal and intestinalized gastric mucosa. We examined cell kinetics and morphological characteristics of human gastric mucosa, using 3H-thymidine autoradiography and scanning electron microscopic fractography. It is shown that in normal and fully developed intestinal metaplasia epithelial cells are regularly renewed within 15-60 days. A potential cancer cell, if it may appear in the otherwise normal mucosa, will be lost within this very short period of time. An experiment using hamsters confirmed this expectation. However, the situation is completely different when the gastric mucosa is in the process of intestinalization. Drastic rebuilding (Umbau) is taking place in dynamic structure of gastric gland. SEM fractography revealed this change in three-dimensional pictures. It is concluded that progression of the intestinalization keeps producing a large number of glandular fragments that are embedded in the depth of mucosa making the flow of the cellular turnover stagnant. It is inferred that the stagnation captures a potential cancer cell to make its propagation possible. Therefore, intestinalization can help the cancer cells to propagate in the body of the host. This role of the intestinal metaplasia explains many aspects of their "precancerous" characteristics.
人类胃部最显著的变化，与致癌作用密切相关的是肠化生。为了确定这些黏膜变化与致癌作用之间的相互关系，研究正常和肠化生胃黏膜的结构动态似乎是必要的。我们使用³H-胸腺嘧啶核苷放射自显影术和扫描电子显微镜断口分析法，研究了人类胃黏膜的细胞动力学和形态特征。结果表明，在正常和完全发育的肠化生中，上皮细胞在15 - 60天内定期更新。一个潜在的癌细胞，如果出现在原本正常的黏膜中，会在这非常短的时间内消失。用仓鼠进行的一项实验证实了这一预期。然而，当胃黏膜处于肠化生过程中时，情况则完全不同。胃腺的动态结构正在发生剧烈重塑（Umbau）。扫描电子显微镜断口分析法在三维图像中揭示了这种变化。得出的结论是，肠化生的进展不断产生大量嵌入黏膜深处的腺泡碎片，使细胞更新流动停滞。据推测，这种停滞捕获了一个潜在的癌细胞，使其得以增殖。因此，肠化生可以帮助癌细胞在宿主身体内增殖。肠化生的这一作用解释了其“癌前”特征的许多方面。
