Monell Chemical Senses Center, 3500 Market Street, Philadelphia, PA 19104, USA.
J Chromatogr B Analyt Technol Biomed Life Sci. 2013 Jul 15;931:90-6. doi: 10.1016/j.jchromb.2013.05.007. Epub 2013 May 22.
Dogs can identify, by olfaction, melanoma on the skin of patients or melanoma samples hidden on healthy subjects, suggesting that volatile organic compounds (VOCs) from melanoma differ from those of normal skin. Studies employing gas chromatography-mass spectrometry (GC-MS) and gas sensors reported that melanoma-related VOCs differed from VOCs from normal skin sources. However, the identities of the VOCs that discriminate melanoma from normal skin were either unknown or likely derived from exogenous sources. We employed solid-phase micro-extraction, GC-MS and single-stranded DNA-coated nanotube (DNACNT) sensors to examine VOCs from melanoma and normal melanocytes. GC-MS revealed dozens of VOCs, but further analyses focused on compounds most likely of endogenous origin. Several compounds differed between cancer and normal cells, e.g., isoamyl alcohol was higher in melanoma cells than in normal melanocytes but isovaleric acid was lower in melanoma cells. These two compounds share the same precursor, viz., leucine. Melanoma cells produce dimethyldi- and trisulfide, compounds not detected in VOCs from normal melanocytes. Furthermore, analyses of the total volatile metabolome from both melanoma cells and normal melanocytes by DNACNT sensors, coupled with the GC-MS results, demonstrate clear differences between these cell systems. Consequently, monitoring of melanoma VOCs has potential as a useful screening methodology.
狗可以通过嗅觉识别出患者皮肤或隐藏在健康受试者身上的黑色素瘤，这表明黑色素瘤的挥发性有机化合物 (VOC) 与正常皮肤的 VOC 不同。使用气相色谱-质谱联用 (GC-MS) 和气体传感器的研究报告称，与黑色素瘤相关的 VOC 与正常皮肤来源的 VOC 不同。然而，区分黑色素瘤和正常皮肤的 VOC 的身份要么未知，要么可能来自外源性来源。我们采用固相微萃取、GC-MS 和单链 DNA 涂层纳米管 (DNACNT) 传感器来检测黑色素瘤和正常黑素细胞中的 VOC。GC-MS 揭示了数十种 VOC，但进一步的分析集中在最有可能源自内源性的化合物上。几种化合物在癌细胞和正常细胞之间存在差异，例如，异戊醇在黑色素瘤细胞中的含量高于正常黑素细胞，但异戊酸在黑色素瘤细胞中的含量较低。这两种化合物具有相同的前体，即亮氨酸。黑色素瘤细胞产生二甲基二硫化物和三硫化物，这些化合物在正常黑素细胞的 VOC 中未被检测到。此外，通过 DNACNT 传感器对黑色素瘤细胞和正常黑素细胞的总挥发性代谢物进行分析，并结合 GC-MS 结果，表明这两种细胞系统之间存在明显差异。因此，监测黑色素瘤 VOC 有可能成为一种有用的筛查方法。
