Table 1.
Variant repeats and nuclear receptors present at ALT telomeres
| Cell line | Cell type | Immortalization | C-type variant | G-type variant | TR2 | TR4 | COUP-TF1 | COUP-TF2 | EAR-2 | Telomere maintenance |
| WI38 | Fibroblast; lung | NA | − | − | − | − | − | − | − | Mortal |
| JFCF-6 | Fibroblast; jejunal | NA | − | − | − | − | − | − | − | Mortal |
| GM02063 | Fibroblast; skin | NA | − | − | − | − | − | − | − | Mortal |
| HT1080 | Fibrosarcoma | Tumor | − | − | − | − | − | − | − | Telomerase |
| HeLa | Cervical carcinoma | Tumor | − | − | − | − | − | − | − | Telomerase |
| JFCF-6/T.1F | Fibroblast; jejunal | SV40 | − | − | − | − | − | − | − | Telomerase |
| GM639 | Fibroblast; skin | SV40 | − | − | − | − | − | − | − | Telomerase |
| WI38-VA13/2RA | Fibroblast; lung | SV40 | + | + | + | + | + | + | + | ALT |
| U-2 OS | Osteosarcoma | Tumor | + | APBs onlya | + | + | − | + | − | ALT |
| IIICF/c | Fibroblast; breast, LFSb | Spontaneous | + | APBs only | + | + | + | + | + | ALT |
| JFCF-6/T.1M | Fibroblast; jejunal | SV40 | + | APBs only | + | + | + | + | + | ALT |
| JFCF-6/T.1R | Fibroblast; jejunal | SV40 | + | APBs only | + | + | + | + | + | ALT |
| GM847 | Fibroblast, skin | SV40 | + | APBs only | + | + | + | + | + | ALT |
| SUSM-1 | Fibroblast; liver | Chemical | + | APBs only | + | + | + | + | − | ALT |
| Saos-2 | Osteosarcoma | Tumor | + | APBs only | + | + | − | + | − | ALT |
a
Variant repeat only detected within APBs, not at individual telomeres, by FISH analysis performed on metaphase spreads.
b
LFS, Li-Fraumeni syndrome.