
這系列的第一集,我們講解了PD1/PDL1的運作原理。731Please respect copyright.PENANAPgtfTjZgez
Link: https://www.penana.com/article/471125731Please respect copyright.PENANAMmeg3hDrTA
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第二集我們講述CTLA4與T cell功用的關係。731Please respect copyright.PENANAM362TIExnm
Link:https://www.penana.com/article/472480731Please respect copyright.PENANAmGCrGAusmx
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第三集我們講述增加T cell順利到達癌細胞位置的其中一種手段。731Please respect copyright.PENANAvdTgtbbcCJ
https://www.penana.com/article/479229731Please respect copyright.PENANAHHnSEc2T6j
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而這一集我們將講解一道關於檢測阻擋PD1的抗體Pembrolizumab成效的研究。731Please respect copyright.PENANAqmKou01MeU731Please respect copyright.PENANAmMQniKmr2y
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關於阻檔PD1的原理及初心,可參閱第一集,其後可直接跳過第二第三集來到第四集本集。731Please respect copyright.PENANAgfghbrwmuk
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(圖2)現今約只有20%的病人能夠從免疫治療中獲取長遠且持續的正面效果。731Please respect copyright.PENANA9MJAqUZSkP731Please respect copyright.PENANAyawiao0twe
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其有效的程度實屬可圈可點,如果有方法能夠盡快得知免疫治療沒有預期成效的話,那就可以即時轉用其他治療手段,把握時候嘗試用第二種方法入手打擊癌症。731Please respect copyright.PENANAdlje5gdV4Z
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對此,有科學家嘗試量度血液中癌細胞的DNA含量,觀察能否藉此方法預判免疫治療的效果(Ref1)。731Please respect copyright.PENANAEACMSYIBXg
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(圖3)癌細胞DNA之所以會出現在血液中,主要由兩大途徑所成。731Please respect copyright.PENANAPh0Ehk43Oe731Please respect copyright.PENANAb4moYfgtK4
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1.癌細胞會利用血液循環系統或者淋巴系統轉移到第二個位置,731Please respect copyright.PENANAxAjUUI6MPI
因此血液會有癌細胞的DNA。731Please respect copyright.PENANAoEwGgYMx8r
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2.癌細胞亦會往外釋出名Exosome的物質,裡頭亦含有癌細胞的DNA。731Please respect copyright.PENANANaYXS658Wo
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在這裡,我們暫稱癌細胞在血液中的DNA為ctDNA,Circulating Tumor DNA。731Please respect copyright.PENANAMZdErgfQNn
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(圖4)圖中為利用阻擋PD1的抗體Pembrolizumab作治療的兩名病人結果。731Please respect copyright.PENANAmp1oUPvwDk731Please respect copyright.PENANASUoJay4kSl
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紅線為電腦斷層掃描觀察癌細胞大小的影像,而黑線為量度癌細胞在血液(ctDNA)的含量,可見黑線(量度ctDNA的含量)能夠更快預判免疫治療結果成效。731Please respect copyright.PENANAfK3XInPZ1a
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而且,有另外10名接受免疫治療的病人在初期(服用藥物後6-7星期)錄得ctDNA完全下降,亦同樣能夠比電腦斷層掃描觀察更早一步預判成效。731Please respect copyright.PENANAu2FVaXN9Gp
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而研究中有45名免疫治療的病人在初期沒有錄得任何的ctDNA跌幅,癌細胞的體積在其後亦沒有明顯縮細。731Please respect copyright.PENANAFe0XflW3JU
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對比含放射性的電腦斷層掃描,量度血液的ctDNA只需抽取病人的血液便可,明顯簡單且快捷。731Please respect copyright.PENANAzfU18qlc7Q
只不過每名病人的ctDNA排組均不一樣,先前需要拿取部份癌細胞組織,才能夠有效設計檢測ctDNA的方針。731Please respect copyright.PENANAR74NFftJLr
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無論如何,若然日後能有研究進一步確立此方法的成效及可信性,定必大可增加對抗癌症的效益。731Please respect copyright.PENANAtBxfDkR9lu
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另一方面,透過檢測血液的DNA來預先得知癌細胞的存在,亦是日後檢驗及預防癌症的主流大方向。731Please respect copyright.PENANALMvU9AFQdV
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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。731Please respect copyright.PENANAMfuNxSAHUc
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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/toc731Please respect copyright.PENANA8k67TFYwJr
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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。731Please respect copyright.PENANAtK6RlzyYjd
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Link:731Please respect copyright.PENANAw1tNkg0Ll4
https://www.penana.com/user/27349/%E8%96%AF%E4%BB%94%E8%81%9E%E8%8C%B1%E8%8E%89/portfolio731Please respect copyright.PENANAbO28vjydgN
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有興趣接收科學資訊的話,歡迎follow IG: potatopigtongue。731Please respect copyright.PENANAwPs7GgeIJ9
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https://www.instagram.com/potatopigtongue/731Please respect copyright.PENANA6LqpFthsa8
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Ref1:https://www.nature.com/articles/s43018-020-009731Please respect copyright.PENANAHTVDpYB7lO