Evidence for alternative lengthening of telomeres in liposarcomas in the absence of ALT-associated PML bodies.

摘要: Immortalized and cancer cells maintain their telomeres by activation of a telomere maintenance mechanism (TMM). In approximately 85% cancers telomerase is activated (TA) but in some tumours, particular sarcomas, an alternative lengthening (ALT) pathway used. Liposarcomas are the most common soft-tissue sarcoma adults they activate ALT or with equal frequency, however no TMM has been identified 50% liposarcomas. our study, we have shown that instability at minisatellite MS32, usually associated activation, aids identification liposarcomas recombination-like activity absence PML-bodies (APBs). Furthermore, using single molecule analysis, detected complex mutations directly positive interestingly unknown high MS32 instability. We sequence analysis these must arise inter-molecular process rather than deletion caused t-loop excision unequal telomere-sister-chromatid-exchange (T-SCE), which known to be elevated cell lines. Preliminary evidence also suggests recombination events may processed differently APBs compared those without. conclusion, for first time, negative without other features ALT, indicating incidence tumours previously under-estimated. This major implications use treatments targeted TMMs.