Table 3.
Cell cycle pathway alterations found in study patients by IHC and next-generation sequencing
| IDa | RB IHC | p16 IHC | Gene | Alteration | Predicted sensitivity to palbociclib | PFS4 |
|---|---|---|---|---|---|---|
| 1 |
3+ in 20% 2+ in 40% 1+ in 30% 0+ in 10% |
3+ staining in 30% |
CDKN1A CDKN1A |
Asp28Gly Pro4Leu |
Resistant Resistant |
No |
| 2 |
3+ in 10% 2+ in 20% 1+ in 20% 0+ in 50% |
No staining | CDKN2B | Shallow deletion | Sensitive | No |
| 3 |
3+ in 30% 2+ in 40% 1+ in 30% |
No staining | Nonea | No | ||
| 4 |
2+ in 30% 1+ in 40% 0+ in 30% |
No staining | CDKN2B | Shallow deletion | Sensitive | No |
| 5 |
2+ in 70% 1+ in 20% 0+ in 10% |
No staining | CDKN2B | Deep deletion | Sensitive | No |
| 6 |
2+ in 10% 1+ in 80% 0+ in 10% |
No staining | Nonea | No | ||
| 7 |
3+ in 30% 2+ in 40% 1+ in 30% |
No staining | E2F3 | Gain | Resistant | No |
| 8 |
2+ in 30% 1+ in 70% |
No staining |
CCNE1 CDKN1A CDKN1A |
Gain Asp28Gly Pro4Leu |
Resistant Resistant Resistant |
Yes |
| 9 |
2+ in 30% 1+ in 60% 0+ in 10% |
1 + staining in 90% | RB1 | Amplification | N/A | No |
| 10 |
2+ in 50% 1+ in 30% 0+ in 20% |
No staining | CDKN1A | FS111 | Resistant | Yes |
| 11 |
3+ in 20% 2+ in 20% 1+ in 10% |
No staining | E2F3 | Asp389Asn | Resistant | No |
| 12 |
3+ in 10% 2+ in 30% 1+ in 30% 0+ in 30% |
No staining | Unknowna | No |
aPatients 3 and 6 did not have any cell cycle alterations, patient 12 did not have adequate tissue for sequencing