裸鼴鼠引人矚目之處在于它們壽命極長，同時對癌癥幾乎有完全的抵抗力?，F(xiàn)在,，一個新穎的糖胺多糖變體被發(fā)現(xiàn)是它們抗癌能力的一個關(guān)鍵貢獻因素,。該變體使這種動物具有在地下生活所需的結(jié)實而柔和的皮膚,。透明質(zhì)酸是細胞外基質(zhì)的一個普遍成分,。Xiao Tian等人發(fā)現(xiàn)，裸鼴鼠成纖維細胞的培養(yǎng)介質(zhì)會因一種粘稠物質(zhì)的積累而變得有粘性,，同時他們還識別出該物質(zhì)是一種“高分子量透明質(zhì)酸” (HMM-HA) ，比小鼠和人類的相應(yīng)物質(zhì)大5倍,。它因透明質(zhì)酸酶活性低以及一種獨特形式的“透明質(zhì)酸合成酶-2”的存在而在裸鼴鼠組織中積累,。HMM-HA 通過 CD44 受體發(fā)揮作用，HMM-HA的清除使得裸鼴鼠細胞更易發(fā)生變形,。這種不同尋常的抗癌形式為研究抗癌及壽命延長策略提供了潛在的新途徑,。（生物谷Bioon.com）
生物谷推薦英文摘要：
Nature doi: 10.1038/nature12234
High-molecular-mass hyaluronan mediates the cancer resistance of the naked mole rat
Xiao Tian, Jorge Azpurua, Christopher Hine, Amita Vaidya, Max Myakishev-Rempel, Julia Ablaeva, Zhiyong Mao,Eviatar Nevo, Vera Gorbunova & Andrei Seluanov
The naked mole rat (Heterocephalus glaber) displays exceptional longevity, with a maximum lifespan exceeding 30 years. This is the longest reported lifespan for a rodent species and is especially striking considering the small body mass of the naked mole rat. In comparison, a similarly sized house mouse has a maximum lifespan of 4 years. In addition to their longevity, naked mole rats show an unusual resistance to cancer. Multi-year observations of large naked mole-rat colonies did not detect a single incidence of cancer. Here we identify a mechanism responsible for the naked mole rat’s cancer resistance.We found that nakedmole-rat fibroblasts secrete extremely high-molecular-mass hyaluronan (HA), which is over five times larger than human or mouse HA. This high-molecular-mass HA accumulates abundantly in naked mole-rat tissues owing to the decreased activity of HA-degrading enzymes and a unique sequence of hyaluronan synthase 2 (HAS2). Furthermore, the naked mole-rat cells are more sensitive to HA signalling, as they have a higher affinity to HA compared with mouse or human cells. Perturbation of the signalling pathways sufficient for malignant transformation of mouse fibroblasts fails to transform naked mole-rat cells. However, once highmolecular-mass HA is removed by either knocking down HAS2 or overexpressing the HA-degrading enzyme, HYAL2, naked mole-rat cells become susceptible to malignant transformation and readily form tumours in mice. We speculate that naked mole rats have evolved a higher concentration of HA in the skin to provide skin elasticity needed for life in underground tunnels. This trait may have then been co-opted to provide cancer resistance and longevity to this species.
