1. Supplementary Figure 1 Mdm4 Mdm2 ATM p300 CBP HAUSP pRB p53 CDK4
11: MDA-MB-134VI
13: MDA-MB-175VII
12: MDA-MB-157
14: MDA-MB-231
15: MDA-MB-330
16: MDA-MB-361
17: MDA-MB-415
18: MDA-MB-435S
19: MDA-MB-436
20: MDA-MB-453
21: MDA-MB-468
34: SUM225CWN
36: SUM1315M02
8: HCC1937
22: MPE600
23B: OCUB-M
24: SK-BR-3
25: SK-BR-5
26: SK-BR-7
27: SUM44PE
28: SUM52PE
30: SUM149PT
31: SUM159PT
32: SUM185PE
33: SUM190PT
35: SUM229PE
38: UACC-812
39: UACC-893
41: ZR75-30
1: BT20
2: BT474
4: BT549
5: CAMA-1
6: DU4475
7: EVSA-T
9: Hs578T
10: MCF-7
37: T47D
40: ZR75-1
Mdm4
Mdm2
ATM
p300
CBP
HAUSP
pRB
p53
CDK4
Cyclin D1
PUMA
p21
p16
p14ARF
Tubulin
Tropomysosin
Supplementary Figure 1

2. Supplementary Figure 2 A B *** *** ** *** *** *** *** *** *** *** ** CD
*** * **
*** *
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*** *
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Supplementary Figure 2

3. A B C D
Supplementary Figure 3

4. Supplementary Figure 4 + 10 µM Nutlin-3 Doxorubicin Mdm2 Mdm4
pSer15-p53
pSer46-p53
p53
PUMA
p21
HAUSP
Supplementary Figure 4