 一項研究發現，擁有致癌突變的毛囊干細胞在皮膚受傷的情況下可能引發一種皮膚癌。科研人員已經把人類基底細胞癌（一種有可能導致毀容的皮膚癌）與創傷恢復的缺陷聯系在了一起。毛囊干細胞幫助在受傷后再生組織，但是人們仍然不太清楚它們在引發腫瘤方面的作用。Sunny Y. Wong 和Jeremy F. Reiter培育出了轉基因小鼠，這些轉基因小鼠能產生毛囊干細胞，而這些毛囊干細胞攜帶的一個基因和基底細胞癌有關，該基因可以打開和關閉。打開這個致癌基因并不足以觸發這種小鼠出現癌癥，但是在激活這種致癌基因的同時損傷小鼠的背部皮膚的時候，這組科研人員發現含有這種激活的致癌基因的毛囊干細胞遷移到了受傷部位并且在傷口內部形成了上皮癌樣腫瘤。此外，這組作者發現這些干細胞甚至能在這種致癌基因打開的幾周后出現傷口的時候引發腫瘤。這組作者說，這些發現提示長期存在但是在休眠的位置（諸如毛囊）潛伏的干細胞可能積累致癌突變，直到一個傾覆點（例如受傷） 喚醒了這些細胞并引發腫瘤的形成。
推薦原文出處：
PNAS doi: 10.1073/pnas.1013098108
Wounding mobilizes hair follicle stem cells to form tumors
Sunny Y. Wong and Jeremy F. Reiter1
Abstract
A wide variety of human cancers are associated with injury. Although stem cells participate in tissue regeneration after wounding, it is unclear whether these cells also contribute to epithelial tumors. Human basal cell carcinomas (BCCs) are associated with misactivation of Hedgehog (Hh) signaling, commonly through acquisition of mutations in Smoothened (Smo). We have found that expression of an activated form of Smo by stem cells of the hair-follicle bulge and secondary hair germ does not induce robust Hh signaling or produce BCCs. However, wounding recruits these cells from the follicle to the wound site, where downstream Hh signal transduction is derepressed, giving rise to superficial BCC-like tumors. These findings demonstrate that BCC-like tumors can originate from follicular stem cells and provide an explanation for the association between wounding and tumorigenesis. |
