濕度與氬氣比例對於利用低溫常壓氦氣電漿束進行癌症治療之研究

Abstract

癌症是世界人口死亡原因之首，而肺癌則位居癌症死因之第一位，為了治療肺癌，很多方法被研究出來，而電漿是其中的一種，這種方法被稱為氬氣電漿凝固術（Argon plasma coagulation, APC）。氬氣電漿凝固術常被應用在腸胃道出血及腫瘤燒灼，但是氬氣電漿凝固術有時會造成病人燒燙傷，因此必須尋找其他替代方法。研究顯示，常壓電漿束（Atmospheric pressure plasma jet, APPJ）具有使細胞凋亡（Apoptosis）的效果，此方法可以避免病人燒燙傷，因此，Kim.等人使用低溫常壓氦氣電漿透過細長管線處理癌細胞，研究結果發現其具有促使癌細胞凋亡的效果。另外，由於內視鏡深入肺部治療癌症時電漿束將暴露在與大氣不同程度之濕度下，而一些研究顯示，濕度會影響電漿的效果，因此本研究將探討濕度對於使用低溫常壓氦氣電漿束處理癌細胞的影響。許多研究指出，氫氧根離子是造成癌細胞凋亡的重要原因之一，2010年Seo.等人觀察氬氣及氦氣電漿中所產生的氫氧根離子（·OH）強度，發現氬氣中之氫氧根離子強度較氦氣高出許多，因此，本實驗將混合氦氣及氬氣，觀察氬氣比例對於低溫常壓氦氣電漿束促使癌細胞凋亡的效果。本實驗首先使用MTT方法、Trypan blue染劑、及顯微鏡觀察量測電漿施打過的細胞活性、數量、及型態隨濕度及氬氣比例的改變，接著使用光譜分析儀（Optical emission spectroscopy, OES）觀察電漿束中活性氧物質及活性氮物質（Reactive oxygen and nitrogen species, RONS）的強度隨不同濕度及氬氣比例的改變，再來使用傅立葉衰減全反射紅外線光譜（Attenuated Total Reflection Fourier Transform Infrared spectroscopy，ATR-FTIR）觀察電漿束所施打的溶液中產生的物質鍵結種類，然後使用過氧化氫（H2O2）試劑、對-苯二甲酸（TA）測試、與水質分析儀量測電漿束所施打的溶液中所產生的H2O2、·OH、及NO2-濃度隨濕度及氬氣比例的改變。實驗結果顯示，本研究所使用之內視鏡管容易破裂，且不同內視鏡管線間的實驗結果有差異，未來將使用堅固耐用之電漿頭重複實驗。

Cancer is a leading cause of death worldwide, and lung cancer is a leading cause of cancer-related deaths. In order to treat lung cancer, many therapies have been invented, and argon plasma coagulation （APC） is one of them. APC is usually applied in stanching of bleeding and tumors treatment. However, APC can sometimes injure patients. Therefore, methods other than APC are still in need. Some studies have shown that low temperature atmospheric pressure plasma jet （APPJ） can induce apoptosis in cells. Therefore, Kim. et al. used a flexible optical fiber-based cold microplasma to treat lung cancer cells, and results showed that it was sufficiently effective to induce apoptosis. Nevertheless, APPJ will encounter humid environment different from ambient air when treating lung cancer by using an endoscope, and studies have shown that humidity will influence reactive species generation by plasma. Hence, this study will consider humidity effect on helium low temperature APPJ induced apoptosis in lung cancer cells. Studies have shown that hydroxyl radicals （·OH） play an important role in inducing apoptosis in cancer cells. In 2010, Seo. et al compare the intensity of hydroxyl radicals generation in argon plasma and helium plasma, and results showed that OH line in argon plasma was higher than that in helium plasma. Therefore, in this study we will use helium-argon mixture low temperature APPJ to investigate the effect of argon addition on inducing apoptosis in lung cancer cells. MTT assay, proliferation assay, and observation by microscope were used to investigate effect of the APPJ on inducing apoptosis in cancer cells. Optical emission spectroscopy （OES） was used to measure the changes of intensity of the reactive oxygen and nitrogen species （RONS） under different humidity and argon dosage. Attenuated Total Reflection Fourier Transform Infrared spectroscopy（ATR-FTIR） was used to investigate the bondings of RONS in solutions after APPJ treatment under different humidity and argon dosage. H2O2 and TA tests were used to measure the changes of H2O2 and ·OH concentrations in solutions, and an analyzer was used to measure the changes of NO2- concentration in solutions after APPJ treatment under different humidity and argon dosage. The results showed that the endoscope used in this study was not solid, and there were differences between results got from different endoscopes. A solid plasma jet system will be used to continue the experiments.