Original dataset from Ants act as olfactory bio-detectors of tumours in patient-derived xenograft mice

Early detection of cancer is critical in medical sciences, as the sooner a cancer is diagnosed, the higher are the chances of recovery. Tumour cells are characterized by specific volatile organic compounds (VOCs) that can be used as cancer biomarkers. Through olfactory associative learning, animals can be trained to detect these VOCs. Insects such as ants have a refined sense of smell, and can be easily and rapidly trained with olfactory conditioning. Using urine from patient-derived xenograft mice as stimulus, we demonstrate that individual ants can learn to discriminate the odour of healthy mice from that of tumour-bearing mice and do so after only three conditioning trials. After training, they spend approximately 20% more time in the vicinity of the learned odour than beside the other stimulus. Chemical analyses confirmed that the presence of the tumour changed the urine odour, supporting the behavioural results. Our study demonstrates that ants reliably detect tumour cues in mice urine and have the potential to act as efficient and inexpensive cancer bio-detectors.

癌症早筛在医学领域至关重要，癌症确诊时机越早，患者康复的概率就越高。肿瘤细胞的特征是存在特定挥发性有机化合物（volatile organic compounds, VOCs），这类物质可作为癌症生物标志物。通过嗅觉联想学习，可训练动物识别这类VOCs。诸如蚂蚁的昆虫拥有极为敏锐的嗅觉，且可通过嗅觉条件反射训练实现快速、简便的驯化。本研究以患者来源异种移植小鼠的尿液作为刺激源，证实单只蚂蚁仅需三次条件反射训练试验，即可学会区分健康小鼠与荷瘤小鼠的尿液气味。训练完成后，蚂蚁在习得气味附近停留的时长相较另一刺激源旁多出约20%。化学分析证实，肿瘤的存在会改变小鼠尿液的气味，这一结果为行为学实验结论提供了支撑。本研究证实，蚂蚁能够稳定检测小鼠尿液中的肿瘤信号，具备成为高效且低成本癌症生物检测器的潜力。