TNFRSF8 and cancer: By using an anti-CD30 aptamer that is labeled with paired Cy3 fluorochrome and Black Hole Quencher 2 (Life Technologies Inc., Carlsbad, CA, USA) as a model, when CD30-positive cancer cells were present, the Cy3 fluorescent signal was activated within 10 minutes and was stable for up to 120 min with undetectable background noise.