樟芝防治癌症之重要機轉與特色–癌症逆轉

鄧文炳
臺北醫學大學
根據研究發現癌症是可以逆轉的，以感染病毒或以化學物質處理或與放射線接觸等方式藉著啟動腫瘤細胞中之逆轉作用機制，讓癌細胞不表現腫瘤特性，甚至於恢復成相當程度之正常細胞。所謂癌症逆轉現象(Cancer Reversion)，意指腫瘤細胞回復「部分正常」，而成為不具威脅性地可與人體共存的人癌共生現象。本實驗室已經建立了可供癌症逆轉機制探討的研究模式。樟芝﹐又稱牛樟芝或牛樟菇，是台灣特有的真菌，因無法以人工栽培，因此更顯得珍貴。以其中的多醣體(Polysccharides)、三萜類(Triterpenoids)及超氧歧化酵素(Superoxide Dismutase)為主要的研究份。根據初步研究樟芝有明顯的抑制腫瘤細胞生長及抑制癌病毒作用的效果，且以樟芝進行細胞試驗，結果顯示樟芝具有癌症逆轉的特性。具腫瘤誘發性的HeLa細胞的表面抗原，其具有自磷酸化(Autophosphorylation)活性，是一種細胞的腸鹼性磷酸酵素(Intestinal alkaline phosphatase, IAP)，因此本實驗室嘗試解析IAP表現與腫瘤誘發性之間的關係。實驗結果發現樟芝能夠抑制腫瘤細胞內鹼性磷酸酵素的表現。此外在基因層面的探討，初步實驗結果發現， 樟芝有增強抑癌基因p53表現的趨勢；而對子宮頸癌主要的E6/E7致病因子則有抑制的功效。在動物實驗方面，餵食樟芝對於腫瘤細胞生長確實有抑制的效果。以流式細胞儀技術分析樟芝對癌細胞的影響，可能並非走細胞毒殺的路徑，因此可以更加的推斷藥物對細胞的作用是進行癌症逆轉的模式。 關鍵字：癌症逆轉、子宮頸癌細胞、腸鹼性磷酸酵素(IAP)、致癌基因E6/E7、抑癌基因p53、樟芝
關鍵字：癌症逆轉；子宮頸癌細胞；腸鹼性磷酸酵素；致癌基因；抑癌基因；樟芝

Cancer reversion model as a character of Taiiwanofungus camphoratus for cancer prevention

Win-Ping Deng Ph.D.
Taipei Medical University
Neoplastic transformation of normal cells can occur spontaneously or can be induced by viruses, chemical carcinogens, or irradiation. Such transformed cells; however, can also spontaneously, or be induced to, lose some of their tumorgenic characteristics and revert back to a more normal phenotypic state through correction of malignant behavior by microenvironmental cues. It has been suggested that the frequency of cell reversion to the non-tumorigenic phenotype is much higher than re-reversion to the tumorigenic phenotype, and that the reversion is paralleled by a regulation in malignant behavior and tumorigenicity. Such reversion may be a consequence of both genetic and epigenetic processes. One of the most challenging goals of cancer therapy is to exploit the potential of such reversion. Meeting this goal requires the identification of agent(s) with the ability to arrest tumor growth while having minimal effect on normal tissue.
關鍵字：Cancer Reversion；IAP；E6/E7；p53；HeLa cell；Taiwanofungus camphoratus