Together with the observation that, on one hand, the co-localization of telomeres with PML is not always observed in ALT+ tumors [13, 28] and, on the other hand, the ALT phenotype is not always confirmed in tumors defined as APB+ [29], we believe that the screen for APBs is not a robust assay for ALT tumor detection. Here, RNPEP is linked to neoplasm.