本帖最後由 goodcat1111 於 2009-8-18 23:45 編輯
作者：Barbara Boughton
出處：WebMD醫學新聞
August 3, 2009 (加州舊金山) —「電子鼻」研發的進步，已經可以從病患的呼吸中偵測肺癌，詳情發表於由肺癌研究國際協會所主辦的第13屆肺癌世界研討會(WCLC)。在記者會中，主要研究者、科羅拉多大學癌症中心的Nir Peled博士，預測在幾年內，這類型的檢測就可以在臨床運用。
這些檢測所仰賴的科技，是對肺癌病患呼吸中的有機成分(VOCs)進行偵測。不過，這些VOCs的來源尚不清楚。
藉由奈米科技，研究者發現，肺癌病患呼吸中特定的VOCs因為腫瘤細胞的代謝而增加。根據Peled醫師等人表示，他們希望此一訊息可以用於發展顯示出各種癌症之不同VOCs的檢測方式，且提升檢測準確度。
在他們的研究中，研究者培育非小細胞肺癌(NSCLC)線、小細胞肺癌線、胰臟癌細胞線，將它們與控制組進行比較。使用氣相層析質譜儀(Gas-chromatography mass spectrometry)分析癌細胞與正常細胞線中的VOCs；研究者也使用一個有18個感應器的電子奈米科技鼻檢測這些細胞。Peled醫師表示，感應器對每個VOC產生不同的訊號。他指出，這些感應器相當細小，數千個才等同於一根人類頭髮。他表示，我們的目標是追蹤肺癌病患呼出氣體中的有機成分來源，確認這些成分在每種癌症中是屬獨特或共通。
研究者發現，在各種癌細胞(NSCLC、SCLC以及胰臟癌)檢測中，許多VOCs是獨特的。他們的奈米科技感應器可以有相當高的敏感度分辨不同癌症。例如，NSCLC有5種獨特的VOCs，研究者在90%的NSCLC病患呼吸中分離出其中3種。
Peled醫師聲稱，癌症之嗅覺檢測(sniff tests)在最近幾年被廣為宣傳。狗也可以嗅出哪些人有癌症，但敏感度只有35%至40%。在2007年，克里夫蘭診所的研究者發表一篇癌症呼吸檢測研究，但是該檢測只有在4個病患中分辨其中3人有肺病或肺癌(Thorax. 2007；62:565-568)。有其他研究者研發偵測皮膚癌的電子鼻，且成功使用奈米科技分辨基底細胞癌之氣味資料。
不過，Peled醫師的團隊希望研發更準確且更敏感的檢測。他們的下一步是動物與人類研究，且已經開始著手進行。
無論肺癌嗅覺檢測是否真可實際運用，依舊值得討論。科羅拉多大學癌症中心主任、肺癌研究國際協會執行長Paul Bunn醫師表示，偵測肺癌病患呼吸中VOCs的科技仍有改善空間。蒐集樣本很簡單，困難之處在於分析。Bunn醫師指出，在任何肺癌嗅覺偵測方式正式作為診斷工具之前，需要有更多病患的更大型研究。雖然研究者希望在幾年內有這種檢測上市，若未能如願也不令人意外。
Peled醫師與 Bunn醫師宣告沒有相關財務關係。
第13肺癌世界研討會(World Conference on Lung Cancer (WCLC))：摘要B3.5。發表於2009年8月2日。
More Sensitive "Electronic Nose" Detects Lung Cancer From Breath
By Barbara Boughton
Medscape Medical News
August 3, 2009 (San Francisco, California) — Progress made in the development of an "electronic nose" that can detect lung cancer from a patient's breath was detailed here at the at the 13th World Conference on Lung Cancer (WCLC), organized by the International Association for the Study of Lung Cancer. In a press conference, lead researcher Nir Peled, MD, PhD, from the University of Colorado Cancer Center in Denver, predicted that such a test could be ready for the clinic in a few years.
The technology behind these tests relies on the detection of volatile organic compounds (VOCs) in the breath of lung cancer patients. However, the origins of these VOCs have been unclear.
Using nanotechnology, the researchers found that specific VOCs in the breath of lung cancer patients arise from a metabolic pathway in tumor cells. They hope this information can be used to develop a test that can pinpoint VOCs in different kinds of cancers with more accuracy than ever before, according to Dr. Peled and colleagues.
In their study, the researchers grew nonsmall-cell lung cancer (NSCLC) lines, small-cell lung cancer lines, and pancreatic cancer cell lines, and compared them with controls. Gas-chromatography mass spectrometry was used to analyze the VOCs in the cancerous and normal cell lines; the researchers also tested the cells with an electronic nanotechnology "nose" using 18 sensors. Each VOC produces a different signal from the sensors, Dr. Peled said. The sensors are so tiny that thousands will fit on a human hair, he added. "Our aims were to track the source of the smells in the exhaled breath of cancer patients, and to find what compounds are unique or common to each kind of cancer," he said.
The researchers found several VOCs that were unique to each type of cancer cell tested (NSCLC, SCLC, and pancreatic). Their nanotechnology-based sensors could distinguish the cancers with a high degree of sensitivity. For example, NSCLC had 5 unique VOCs, and 3 of them were isolated in the breath of more than 90% of NSCLC patients tested by the researchers.
Dr. Peled acknowledged that "sniff tests" for cancer have received much publicity in recent years. Dogs can sniff out people with cancer, but their sensitivity is only 35% to 40%. In 2007, a study on a breath test for cancer was published by Cleveland Clinic researchers, but the test could only identify 3 of 4 people with lung disease or lung cancer (Thorax. 2007;62:565-568). Other researchers are developing an electronic nose for skin cancer, and have been successful in using nanotechnology to identify odor profiles for basal cell carcinoma.
However, Dr. Peled's group hopes to develop a more accurate and sensitive test. Their next step is animal and human studies, which they have already begun.
Whether or not a sniff test for lung cancer will ever become a reality is still open to question. "The technology for detecting VOCs in cancer patients' breath has improved considerably," said Paul Bunn, MD, director of the University of Colorado Cancer Center and executive director of the International Association for the Study of Lung Cancer. "Collecting the sample is easy — what's complex is the analysis." Dr. Bunn noted that larger trials with more patients will be needed before any sniff test for lung cancer becomes a usable diagnostic tool. "Although the researchers hope to have a test in a few years, no one will be surprised if that doesn't happen," he said.
Dr. Peled and Dr. Bunn have disclosed no relevant financial relationships.
13th World Conference on Lung Cancer (WCLC): Abstract B3.5. Presented August 2, 2009. |
|
