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。380Please respect copyright.PENANAZgdugSkDyB
380Please respect copyright.PENANAlU0x6jl9Ph
380Please respect copyright.PENANAOMrAk2buJJ
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。380Please respect copyright.PENANA0hqPq2LAdV
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。380Please respect copyright.PENANAdKCnvu7cFB
380Please respect copyright.PENANAMhpbzyA9En
(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。380Please respect copyright.PENANAGljO8Wzbiz
380Please respect copyright.PENANAznVFlxJwZM
380Please respect copyright.PENANAbHkfZlgAd6
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。380Please respect copyright.PENANAYboT4IfBXO
380Please respect copyright.PENANACAyoQgE40g
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)。380Please respect copyright.PENANAsU9UGKgj10
380Please respect copyright.PENANA8x6wphjvNm
(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。380Please respect copyright.PENANAEMAL8ggaqd
380Please respect copyright.PENANALNKbO7WiPD
380Please respect copyright.PENANAQhdz6TK9uq
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。380Please respect copyright.PENANAfq5TlN1iLj
380Please respect copyright.PENANASJFhpawodY
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。380Please respect copyright.PENANAhtYp96Zjd0
380Please respect copyright.PENANARfNE1IBq9p
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。380Please respect copyright.PENANARmbZZs6x8B
380Please respect copyright.PENANAmQV5CPyZFu
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。380Please respect copyright.PENANA6YGQSu2wWx
380Please respect copyright.PENANA7PWPEJtAWz
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。380Please respect copyright.PENANAYx1qnJAUVO
380Please respect copyright.PENANANvHcbkvJQW
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。380Please respect copyright.PENANApLVDmMfnL4
380Please respect copyright.PENANAzjAMatJIzx
380Please respect copyright.PENANArAOyKArRxn
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。380Please respect copyright.PENANANElp3y0GfP
380Please respect copyright.PENANAs7pcbPdYSw
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/toc380Please respect copyright.PENANAqh4DZzS214
380Please respect copyright.PENANAEJZf39ATIO
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。380Please respect copyright.PENANAFDxW5bvpky
380Please respect copyright.PENANAiguDa0M32u
Link:380Please respect copyright.PENANAuYoSXIvUJh
https://www.penana.com/user/27349/%E8%96%AF%E4%BB%94%E8%81%9E%E8%8C%B1%E8%8E%89/portfolio380Please respect copyright.PENANASAdtSWqWc4
380Please respect copyright.PENANA7tPFQYyNhf
有興趣接收科學資訊的話,歡迎follow IG: potatopigtongue。380Please respect copyright.PENANAJsG0jvXQhn
380Please respect copyright.PENANARBhJ276tzl
https://www.instagram.com/potatopigtongue/380Please respect copyright.PENANA2Qw3ijTArh
380Please respect copyright.PENANA4aqQqdLaTf
380Please respect copyright.PENANA9cbiJSL4Tw
Ref1:https://www.nature.com/articles/s42255-020-0253-2