透過進食，我們能夠從食物中獲取身體所需的能量。這過程亦稱之為新陳代謝。688Please respect copyright.ＰＥＮＡＮＡoBw9M6k33s
688Please respect copyright.ＰＥＮＡＮＡR2WLH5y079
688Please respect copyright.ＰＥＮＡＮＡ1WBAXlriHO
有無數證據顯示，癌細胞的新陳代謝與正常的細胞有著顯著的分別。688Please respect copyright.ＰＥＮＡＮＡNcSviEXpV5
正因如此，有不少科學家抱有一個信念，希望透過針對癌細胞的新陳代謝來抑止癌細胞的生長，甚至是達消滅癌細胞之效。688Please respect copyright.ＰＥＮＡＮＡ4XSoNWp3rM
688Please respect copyright.ＰＥＮＡＮＡpA08y3hfbA
（圖2）半胱胺酸 (Cysteine)是氨基酸的一種，亦即是組成蛋白質的基本單元。688Please respect copyright.ＰＥＮＡＮＡgD9p6A7HHo
688Please respect copyright.ＰＥＮＡＮＡralpnVqCKU
688Please respect copyright.ＰＥＮＡＮＡDIl4GPPupb
我們可以透過直接進食來攝取Cysteine，又或者依靠肝臟將特定兩隻氨基酸(Methionine及Serine)轉化成為Cysteine供我們所用。688Please respect copyright.ＰＥＮＡＮＡkRfdqve5Xi
688Please respect copyright.ＰＥＮＡＮＡ2e0xV6EBVL
有科學家嘗試從飼養癌細胞的營養液中剔除Cysteine，發覺部份癌細胞的生長速度有所減慢，而有部份的癌細胞則趨向死亡(Ref1)。688Please respect copyright.ＰＥＮＡＮＡupa46m7JuO
688Please respect copyright.ＰＥＮＡＮＡvpuPXlWbfJ
（圖3）從營養液剔除Cysteine後，身體攝取Cysteine的辦法便只剩下依靠肝臟將同為氨基酸的Methionine及Serine轉化成為Cysteine。688Please respect copyright.ＰＥＮＡＮＡudq6B6vPEB
688Please respect copyright.ＰＥＮＡＮＡQzsGS2yqPS
688Please respect copyright.ＰＥＮＡＮＡsjjlhxwied
而各種剔除Cysteine便會死亡的癌細胞的共通點，就是缺乏一隻名為5-methylthioadenosine phosphorylase(MTAP)的蛋白酶。688Please respect copyright.ＰＥＮＡＮＡs8EPGhLxdl
688Please respect copyright.ＰＥＮＡＮＡXdiO4ZkrG9
失去MTAP後，細胞會傾向將Methionine轉化成為一系列名為Polyamine的物質，導致身體失去製作Cysteine的手段。688Please respect copyright.ＰＥＮＡＮＡ2tWmuR0bPG
688Please respect copyright.ＰＥＮＡＮＡww4iA2dAaM
更甚的是，產生Polyamine的過程中將會產生游離基，而制衡游離基的Glutathione卻則依靠Cysteine作為原材料。688Please respect copyright.ＰＥＮＡＮＡyvxUsfbsus
688Please respect copyright.ＰＥＮＡＮＡFsdGB6h995
因此，缺乏MTAP的癌細胞若然沒有外來Cysteine供應的話，便會因游離基數量過多而導致死亡。688Please respect copyright.ＰＥＮＡＮＡB01EzcTKjE
688Please respect copyright.ＰＥＮＡＮＡsiDo95uEmU
環觀各種癌細胞，膠質母細胞瘤（Glioblastoma)有較大的機會因基因變異而失去MTAP基因。688Please respect copyright.ＰＥＮＡＮＡGp9vz5Hlg6
688Please respect copyright.ＰＥＮＡＮＡmQbzNdrQGL
根據上述研究結果，若癌症病人的癌細胞證實缺乏MTAP基因的話，在餐單中剔除進食Cysteine氨基酸或許是一個副作用相對上為微的理性選擇。688Please respect copyright.ＰＥＮＡＮＡuG57qPpFMk
688Please respect copyright.ＰＥＮＡＮＡYOvpZBQITj
688Please respect copyright.ＰＥＮＡＮＡ1Ta06G6kYC
如果想我快啲出文的話，請入去Penana網站科普專欄–薯不揀單俾一個like以及Bookmark，這對我非常之重要。688Please respect copyright.ＰＥＮＡＮＡRxeJrOF1cV
688Please respect copyright.ＰＥＮＡＮＡLBYlsu2nkt
Link: https://www.penana.com/story/66244/%E7%A7%91%E6%99%AE%E5%B0%88%E6%AC%84-%E8%96%AF%E4%B8%8D%E6%8F%80%E5%96%AE/toc688Please respect copyright.ＰＥＮＡＮＡQ7B9UgO9w1
688Please respect copyright.ＰＥＮＡＮＡp0XQHog1Cn
同時亦可以在Penana網站裡按「買一嚿/半嚿薯仔」，以課金的方式推動我繼續搜羅資料寫文，多謝。688Please respect copyright.ＰＥＮＡＮＡ4qdhpq3ClD
688Please respect copyright.ＰＥＮＡＮＡvQvHGW5mNl
Link:688Please respect copyright.ＰＥＮＡＮＡHCyTu3fOuL
https://www.penana.com/user/27349/%E8%96%AF%E4%BB%94%E8%81%9E%E8%8C%B1%E8%8E%89/portfolio688Please respect copyright.ＰＥＮＡＮＡsbWgf3FvU6
688Please respect copyright.ＰＥＮＡＮＡsfteobLJ71
有興趣接收科學資訊的話，歡迎follow IG: potatopigtongue。688Please respect copyright.ＰＥＮＡＮＡG99aXRYg14
688Please respect copyright.ＰＥＮＡＮＡ5nKztQuEvv
https://www.instagram.com/potatopigtongue/688Please respect copyright.ＰＥＮＡＮＡnCG3yZTECw
688Please respect copyright.ＰＥＮＡＮＡBMOBb3ov5B
688Please respect copyright.ＰＥＮＡＮＡQWzRJoarjx
Ref1:https://www.nature.com/articles/s42255-020-0253-21234 copyright protection684ＰＥＮＡＮＡ8sweFTnvgP 尼

216.73.216.217