Cells can take up cysteine or synthesize it de novo from methionine, but synthesis alone does not meet the high demands of cancer cells to proliferate. In this issue, Zhu et al. (2019) identify the SAH:SAM ratio, indicative of the cellular methylation state, as limiting for effective cysteine synthesis and the growth of some tumors.

中文翻译：

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硫磺化途径产生，肿瘤产生。

细胞可以吸收半胱氨酸或从蛋氨酸重新合成半胱氨酸，但是仅合成就不能满足癌细胞增殖的高要求。在本期中，Zhu等人。（2019）确定SAH：SAM比值（表示细胞甲基化状态）限制了有效的半胱氨酸合成和某些肿瘤的生长。