Transcript Research Presentation 5 28 14

The Role of Anti-PD1 Antibody
in Combination with Radiation
Therapy in an Orthotopic Lung
Cancer Mouse Model
Meredith Baker, MD
PI: Bo Lu, MD – Radiation Oncology
May 29th, 2014
Lung Cancer
• More people in the United States die from lung cancer than
any other type of cancer
• In 2010,
• 201,144 people in the United States were diagnosed with lung
cancer
• 158,248 people in the United States died from lung cancer
• 5 year survival rates vary based upon stage at diagnosis, but
overall range from 1-49%
Antibody Therapeutics in Cancer
• Over the past 16 years, the advent of “targeted”cancer
therapies has emerged
• This involves the use of drugs developed to inhibit oncogenic
proteins or survival factors selectively expressed by tumors
• There are currently 13 antibodies approved by the FDA for
various oncologic indications
• Hematologic cancers
• Solid tumors - EGFR and HER2
• Ipilimumab – CTLA4
PD-1 and PD-L1
Sliwkowski, Mark X., and Ira Mellman.
Science 341.6151 (2013): 1192-8
Radiation Therapy
• The combination of radiation therapy and immunotherapy
holds particular promise as a strategy for cancer
therapeutics
• Radiation induced tumor-cell death as a potential source of
tumor antigens for immunotherapy
• Post-radiation tumor-cell modulation that allows more efficient
immune-cell access
Radiation Therapy
Hypothesis #1
• Treatment of cells with radiation therapy will increase
expression of PD-L1 and PD-1
Effect of Radiation Therapy
• Injected mice with Lewis lung carcinoma (LLC) cells
• After 10 days, the tumors were treated with 25Gy radiation.
• Three days post radiation therapy, spleen, lymph nodes and
tumors were harvested.
No treatment
IFNγ
20Gy
PD-L1 expression
Effects of Radiation Therapy on PD-L1 Expression
0.91%
0.54%
77.6%
89.1%
75.8%
70.6%
Effects of Radiation Therapy on PD-1 Expression
Post-irradiation (25Gy)
PD-1
No irradiation
Lymph nodes
1.71%
40.8%
Tumor
9.77%
27.5%
Summary of evidence
• Radiotherapy increases tumor antigen expression
• Increased antigen expression leads to increased T cell
activation
• Increased T cell activation leads to IFNγ production
• IFNγ increases PD-L1 expression
• Radiotherapy increases PD-L1 expression
• Combining anti PD-1 mAb treatment and radiotherapy
decreased tumor size in a triple negative breast cancer
model
Hypothesis #2
Adding anti-PD-1 antibody to a radiation therapy
treatment regimen will augment tumor killing in an
orthotopic lung cancer model
Experimental Plan
• Does combining PD-1 or PD-L1 inhibition with RT enhance
anti-tumor treatment?
• Black/6 mice are injected with 2x105 Lewis lung carcinoma cells
into their flank (total volume 50μL).
• Irradiate mice
• Groups split into 12Gy and 20Gy
• Add α-PD-1
• Will inject PD-1 antibody at scheduled times
• Monitor tumor burden
• Assess changes in T cell activation
• Collect spleen, LNs, tumor (TILs)
• Isolate lymphocytes
Tumor Growth Delay After Irradiation and
Injection with Anti-PD-1 Antibody
4000
Tumor volume (mm3)
3500
3000
2500
mIgG
12Gyx3+mIgG
12Gyx3+G4
20Gyx3+mIgG
20Gyx3+G4
Day
RT
Ab
(ug)
0
1
2
X
20
0
20
0
3
4
5
X
10
0
6
7
8
9 10 11 12 13 14
X
10
0
10
0
2000
1500
1000
500
0
0
3
7
Time (d)
11
14
10
0
Expression of PD-1 on CD8 cells after Irradiation
and Injection of anti-PD1 antibody
12Gy + IgG
12Gy + G4
20Gy + IgG
PD-1
0.73%
20Gy + G4
3.71%
Abscopal Effect of Radiation Therapy
and Anti-PD-1 Antibody
Tumor Receiving
Direct Irradiation
700
Tumor Volume
600
Tumor Receiving
Abscopal Treatment
700
mIgG
mIgG
600
anti-PD-1
anti-PD-1
500
500
mIgG + RT
mIgG + RT
400
300
300
200
200
100
100
0
0
0
3
anti-PD-1 + RT
400
anti-PD-1 + RT
7
11
14
0
3
Time post-irradiation (d)
7
11
14
Conclusions
• Radiation therapy induces PD-L1 and PD-1 expression
• Combination anti-PD1 antibody and radiation therapy has an
ablative effect on tumor growth
• Combination anti-PD1 antibody and radiation therapy
demonstrate abscopal effects in this murine model
Thank You
•
•
•
•
Bo Lu, MD, PhD
Hannah Myers, MS
Nathaniel Evans, III MD
Scott Cowan, MD
Works Cited
•Brahmer, Julie R., et al. "Safety and Activity of Anti–PD-L1 Antibody in
Patients with Advanced Cancer." N Engl J Med 366.26 (2012): 2455-65.
Web.
•Sliwkowski, Mark X., and Ira Mellman. "Antibody Therapeutics in
Cancer." Science 341.6151 (2013): 1192-8. Web.
•Topalian, Suzanne L., et al. "Safety, Activity, and Immune Correlates of
Anti–PD-1 Antibody in Cancer." N Engl J Med 366.26 (2012): 2443-54.
Web.
•Verbrugge I et al. “Radiotherapy increases the permissiveness of
established mammary tumors to rejection by immunomodulatory
antibodies.” Cancer Res 72.13 (2012): 3163-74