Cristel V Camacho, PhD
Sandeep Burma, PhDDepartment of Radiation Oncology
June 27, 2013
Genetic Events Underlying Radiation-Induced Gliomagenesis
The Space Radiation Problem
Galactic Cosmic Rays (GCR) • Protons (85%)• Alpha particles (14%) • High atomic number and high energy (HZE) particles (1%)
science1.nasa.gov
Solar Energetic Particles
Galactic Cosmic Rays
Solar Energetic Particles • Solar particle events• Coronal mass ejections
NASA needs to close the knowledge gap on a broad range of biological questions
X-rays 1 GeV/n Fe
γ
science1.nasa.gov
Ionizing Radiation and Carcinogenesis
NASA Space Radiation Laboratory (NSRL)
I. DNA damage responses to gamma- versus particle- irradiation
II. Cellular transformation by gamma- versus particle- irradiation
III. Mouse models of radiation-induced gliomagenesis
science1.nasa.gov
Mukherjee B, Camacho CV, et al., DNA Repair 2008
I. DNA damage responses to HZE particles versus gamma-raysG
amm
a1
GeV
/n F
e
• Fe ions produce more complex DNA damage• Fe ion-induced damage is incompletely repaired
- persistent DNA damage signaling- damage-induced senescence- reduced cell survival
0 1 2 3 40.001
0.01
0.1
1
Gamma rays
1 GeV/n Fe
Dose (Gy)
Su
rviv
al
• What are the long term carcinogenic consequences of persistent DSBs such as those induced by Fe ions?
Sur
viva
l
Dose (Gy)
1 GeV/n FeGammaMock
~3% ~84%~24%
1 GeV/n FeGamma
p53
actin
p21
p16/Ink4a
p53 (ser15)
0.5
h24
h
1 GeV/n Fe
γH2AX
53BP1
γH2AX
1 GeV/n Fe
Gamma
% f
oci r
em
aini
ngTime (hrs)
NSCs
Astrocytes
II. Ink4a/Arf-null astrocytes: A sensitive paradigm for rapidly evaluating the tumorigenic potential of HZE particles
IR
Tumor suppressor lossInk4a/Arf-/-
Oncogene activation Tumorigenesis
McEllin B, Camacho CV, et al., Cancer Research 2010Mukherjee B, McEllin B, Camacho CV, et al., Cancer Research 2009
p19/Arf
Exon 1β Exon 1α Exon 2 Exon 3
p16/Ink4a Cyclin DCDK 4/6
pRB
MDM2 p53IR Ink-/-, Pten-/-,EGFR; NSC
Gam
ma
4Gy
Fe
1 G
yMock IR
0 20 40 600
50
100
150
200
250FeGamma
Mock (0/8)g 1Gy (0/8)g 4Gy (2/8)Fe 1 Gy (12/12)
DAY
Ink4a/Arf-/- astrocytes irradiated with Fe ions are potently tumorigenic
Vo
l m
m3
Exon 1β Exon 1α Exon 2 Exon 3
p16/Ink4a
p19/Arf
Exon 2Exon 1
p15/Ink4b
#2#1
Tumor
Ch 4
0 10 20 30 400
100
200
300
400
500
p 1 5C o n tro l C o n tro l (12 /12 )
p 15 (12 /12 )
D AY
Vo
lmm
3
Ctrl p15
Fe 1 Gy (acute)3 months post-IR
Mock Fe
Days Post-IR
0 100 200 3000
20
40
60
80
100
Fe (n=40) (10)
Mock-IR (n=40) (0)
NesCre; Ink4ab-/-/Arf f/f
X-Rays (n=40) (10)Tum
or f
ree
surv
ival
III. Transgenic mouse models of radiation-induced gliomagenesis
Ink4a/Arf f/f Ink4a-/-;Ink4b-/-;Arf f/f Ink4a-/-;Ink4b-/-;Arf f/fPTEN f/+
Ink4a+/+;Arf+/+
Rapid induction of high-grade gliomas by DNA double-strand breaks
Genomic amplification of Met is a frequent event in radiation-induced gliomas
Met
Amp
Non-Amp
Met FISHAmp
Non-Amp
Met
pMet
pMet
Sox2
Actin
Par βGal Met
V5-tagged
Met
V5
βGal MetMet
Sox2
Merge
βGal Met
NS
CS
oft-
agar
βGal Met
Project Overview
Nestin-Cre Ink4a/Arf f/f
Nestin-Cre Ink4ab-/-;Arf f/f
Nestin-Cre Ink4ab-/-;Arf f/f
PTEN f/+Nestin-Cre
Ink4a+/+;Arf +/+
Mock-IR
1Gy Fe (600 MeV/n)
4Gy Gamma-rays
40
40
40
40
40
40
40
40
40
40
40
40
HZE particles vs Gamma-rays
Molecular Profiling and Validation
RNA Expression ProfilingWhole Genome aCGH Copy
Number Analysis
Radiation Protection/Mitigation
Acknowledgements
Sandeep Burma, PhDBipasha Mukherjee, PhDNozomi Tomimatsu, PhDXiaohuan Gao, PhDBrian McEllin, PhDMariya IlchevaCarlos Gil del AlcazarPavlina TodorovaMolly Gillam
UTSWMichael D Story, PhD Liang-Hao Ding, PhDDebabrata Saha, PhD Amyn A Habib, MDXian-Jin Xie, PhDKimmo Hatanpaa, MD, PhD
Adayabalam S Balajee, PhD (Columbia U.)
Funding
CBP Training Grant (PI: Jerry Shay, PhD)
NASA
BNL/ NSRLPeter Guida, PhDAdam Rusek, PhD
Thesis CommitteeRobert M Bachoo, MD, PhDDavid A Boothman, PhD Chaitanya S Nirodi, PhD
Past MembersBrandon Hahm, MDNandini PichamoorthyKaushik AmancherlaKatherine Deland