IS THERE A ROLE FOR RADIATION THERAPY AND IMMUNOTHERAPY? S. Lewis Cooper, M.D. Assistant Professor, Radiation Oncology Hollings Cancer Center Medical University of South Carolina (MUSC) DISCLOSURE Abney Clinical Scholar OBJECTIVES • Review mechanisms of immune escape by cancer cells • Review radiation effects on the immune system • Review current strategies to combine RT and immunotherapy • IL-2 • Dendritic cell production • Tumor antigen vaccine • CTLA-4 antibody/PD-1antibody • TLR agonist • TGF-β antibody CANCER IMMUNOEDITING CD8+ NKT CD8+ T cell cell T cell • Three phases: NK CD4+ T cell • Elimination – Innate and adaptive immune systems detect INF-γ IL-12 and destroy developing tumor before it is clinically TNF TRAIL apparent. Mφ Perforin γδ T DC CD8+ IL-12 cell T cell CD4+ INF-γ T cell • Equilibrium – The immune system maintains residual tumor cells in a functional state of dormancy. Protection Mφ CD8+ NK T cell TGF-β PD-L1 IL-6, IL-10 • Escape – Tumor cells that aquire the ability to escape Galactin-1 IDO Antigen Loss immune recognition and destruction emerge as growing MHC Loss tumors. CD8+ T cell CTLA-4 CTLA-4 PD-1 PD-1 CD8+ MDSC Treg Science . 2011;331:1565-70 T cell MECHANISMS OF ESCAPE • Loss of tumor antigen expression 1. Tumor cells that do not express strong rejection antigens. 2. Loss of MHC class 1 proteins that present these antigens 3. Loss of antigen processing function • Immunosuppresive state in the tumor microenvironment 1. Production of immunosuppresive cytokines (VGEF, TGF-β, galectin, IDO) 2. Recruitment of immunosuppressive cells (Treg, MDSCs, TAMs) Science . 2011;331:1565-70 RADIATION EFFECTS ON THE IMMUNE SYSTEM • Upregulation of HLA, presentation of TAAs, FAS expression Vascular normalization Low • May restore immune effector recognition and immune- T cell infiltration mediated cell death Increase peptides • Skewing of cytokines to inflammatory repertoire; Increase ICAM-1 and FAS RT upregulation of co-stimulatory molecules Upregulate MHC-1 Dose • Upregulation of chemokines, adhesion molecules Chemokine release (VCAM-1, E-selectin, ICAM-1) Activation and expansion • Restoration of regulated APC trafficking of tumor specific CD4 and CD8 T cells • Upregulation of co-stimulatory molecules Increased dendritic cell High • Suppressive - Increase Tregs and activate TGF-β uptake and presentation of TAA (Calreticulin, HMGB1) PNAS. 1989;86:10104-7 J Immunol. 2003;170:6338-47 Cancer Res. 2004:64:7985-94 J Immunol. 2008;180:3132-9 Nat Med. 2007;13:1050-9 Front Oncol. 2012;2:90 J Clin Invest. 1994;93:892-9 EARLY EVIDENCE • 3-methylcholanthrene-induced fibrosarcoma (FSa) • TCD50 – Radiation dose to control 50% of tumors • Normal syngeneic C3Hf/Bu mice TCD50 • Mice with 600 rad whole body irradiation 7000 (WBI) 6000 • Mice permanently immunosuppressed with 5000 thymectomy and 900 rads WBI followed by 4000 syngeneic bone marrow (TxIR) reconstitution. 3000 Rads 2000 • Mice treated with Corynebacterium parvum 1000 0 Control 600 WBI TxIR C. parvum J Natl Cancer Inst . 1979;63:1229-35 RT DOSE AND FRACTIONATION RT DOSE & FX AND IMMUNE RESPONSE • WT or nude mice injected with B16 melanoma cells 20 Gy x 1 • Increasing immunogenicity of B16 cells did not influence RT mediated regression. • CD8 + 2C transgenic cells CFSE labeled and transferred into mice. 15 Gy x 3 15 Gy x 3 Blood . 2009;114:589-95 RT DOSE & FX AND IMMUNE RESPONSE • Chemotherapy and fractionated RT diminish the effect of RT ablation and + B16 melanoma 4T1 mammary CD8 priming. carcinoma • RT + Ad-LIGHT immunotherapy 15 Gy x 3 Paclitaxel reduces lung metastases 20 Gy x 1 Dacarbazine 12 Gy x 2 Blood . 2009;114:589-95 PRE-CLINICAL AND CLINICAL EVIDENCE IL-2 Mφ IL-2 and TIL CD8+ NK T cell TGF-β PD-L1 IL-6, IL-10 Galactin-1 IDO RT CD8+ T cell CTLA-4 CTLA-4 PD-1 PD-1 CD8+ MDSC Treg T cell IL-2, TIL, +RT • MC-38 adenocarcinoma liver metastases • RT effect thought to be to direct anti-tumor activity. • IL-2 alone activity with local RT. • Dose dependent effect of local RT • Treating ½ liver showed no anti-tumor activity with IL-2 and RT RT J Exp Med . 1990;171:249-63 PILOT STUDY OF RT AND IL2 • Metastatic cancer with at least two sites of n=28 measurable disease. Median Age (range), yrs 48.5 (26-66) Sex Surgery for obtaining tumor Male 21 (75%) for TIL preparation Female 7 (25%) Histology Melanoma 14 (50%) 5 Gy bid x 2-4 fx to one site RCC 12 (43%) Bladder 1 (3.5%) Sarcoma 1 (3.5%) IL-2 at 720,000 IU/kg q8 hr x 15 planned RT Site doses +/- TILs to start 2-24 hrs after RT Lung parenchyma 7 (25%) Lung hilum/mediastinum 5 (18%) Adrenal 3 (11%) Bone 4 (14%) IL-2 cycle 2 after 7-10 day break Soft tissue 5 (18%) Abdominal mass 3 (11%) Liver 1 (4%) J Immunother . 1991;12:265-71 PILOT STUDY OF RT AND IL2 • 5 patients received TIL – one PR in field. RT field Outside RT (%) field (%) Complete Response 1 (4) 0 (0) Partial Response 3 (11) 2 (7) • Why no benefit? Stable Disease 13 (46) 5 (18) Progressive Disease 8 (29) 20 (71) • RT dose too low? Inevaluable 3 (11) 1 (4) Overall Response (CR+PR) 4 (14) 2 (7) • RT field to large? J Immunother . 1991;12:265-71 PHASE I STUDY OF SBRT AND IL2 • Metastatic melanoma or RCC with at least 2009-2010 n=12 one lesion amenable to SBRT in the lung, Median Age (range), yrs 61 (51-65) mediastinum, or liver and at least one other Sex site not treated with SBRT. Male 10 (83%) Female 2 (17%) Histology 20 Gy x 1 fx to one site (2 fx in Melanoma 7 (58%) cohort 2 and 3 fx in cohort 3) RCC 5 (42%) SBRT Site Peripheral lung 5 (42%) IL-2 at 600,000 IU/kg q8 hr x 14 planned Central lung 2 (17%) doses to start 3 days after SBRT Mediastinum 1 (8%) Liver 4 (33%) SBRT site max diameter (range), cm 1.8 (0.5-6.1) IL-2 cycle 2 after 16 day break Re-image and repeat IL-2 course if regression Sci Transl Med . 2012;137:137ra74 PHASE I STUDY OF SBRT AND IL2 CT (%) PET (%) Complete Response 1 (8.4) 6 (50) Partial Response 7 (58.3) 2 (16.7) Stable Disease 1 (8.4) 1 (8.4) Progressive Disease 3 (25) 3 (25) Overall Response (CR+PR) 8 (66.7) 8 (66.7) Melanoma (n=7) CR 1 (14.3) 5 (71.4) PR 4 (57.1) 0 RCC (n=5) CR 0 (0) 1 (20) PR 3 (60) 2 (40) • ORR for melanoma 71% was > 16% historical for IL-2. • Of 8 responding patients – 6 maintained response median 480 days. Sci Transl Med . 2012;137:137ra74 PHASE I STUDY OF SBRT AND IL2 • Responders had a higher frequency of proliferating FOXP3 -, Ki67 + CD4 + TEM phenotype cells as well as CD8 + TEM phenotype at baseline and through day 15. Sci Transl Med . 2012;137:137ra74 RT AND IL2 • What will be the role of high dose IL-2 as other immunotherapy strategies evolve and play a more prominent role? Samples of Ongoing Clinical Trials of IL-2 and RT Primary Trial ID Accrual Goal Design Histology Endpoint Arm 1: High-Dose IL-2 alone NCT01416831 44 Metastatic Melanoma ORR (Phase II) Arm 2: High Dose IL-2 and SBRT (20 Gy x 1 or 20 Gy x 2) Arm 1: High-Dose IL-2 alone NCT01416831 84 Metastatic Melanoma ORR (Phase II) Arm 2: High Dose IL-2 and SBRT (20 Gy x 2) NCT01896271 26 High Dose IL-2 and SBRT (20 Gy x 1-3 fx) Metastatic Clear Cell RCC ORR (Phase II) C PRE-CLINICAL AND CLINICAL EVIDENCE Mφ DENDRITIC CELL (DC) CD8+ NK T cell Flt3-L TGF-β PD-L1 IL-6, IL-10 GM-CSF PRODUCTION Galactin-1 IDO DC MHC Loss RT DC CD8+ DC T cell CTLA-4 CTLA-4 PD-1 PD-1 CD8+ MDSC Treg T cell RT ABSCOPAL EFFECT IMMUNE MEDIATED • Metastatic mouse mammary carcinoma 67NR or A20 lymphoma -> injected s.c. into syngeneic mice in 2 sites -> treatment when primary tumor 100-150 mg 1. Control Control RT 2. DC growth factor Flt3-L Flt3-L 3. RT (2 Gy x 1 or 6 Gy x 1) to 1 o o 4. RT to 1 + Flt3-L RT + Flt3-L In nude mice -> no secondary tumor growth delay with Flt3-L + RT RT RT + Flt3-L Int J Radiation Oncology Biol Phys . 2004;58:862-70 RT + GM-CSF – PROOF OF PRICIPLE TRIAL • Stable or progressing metastatic solid 2003-2012 n=41 tumors with at least 3 distinct sites of Median Age (range), yrs 62 (54.5-69.5) measurable disease. Maintained on single Sex Male 8 (20%) agent chemotherapy or hormonal therapy. Female 33 (80%) Number of previous therapies RT 1 (0-3) 35 Gy in 10 fx to Chemotherapy 3 (2-4) one metastasis Number of measurable lesions Chest 2 (1-3) Abdomen 0 (0-0.5) GM-CSF 125 µg/m 2 daily Pelvis 0 (0-0) for 2 weeks starting week Any site 3 (2-4) two of RT Number of patients with lesions 3 lesions 21 (51%) 4-6 lesions 15 (37%) Course repeated to > 6 lesions 5 (12%) 2nd lesion starting d22 Lan cet Oncol. 2015;16:795-803 RT + GM-CSF – PROOF OF PRICIPLE TRIAL • Simon’s optimal two-stage design: Patients Not Assessable for best assessable abscopal response Patients could only be enrolled in stage for best 2 if at least one among the first 10 had abscopal PD/SD PR/CR an abscopal response.