Biological Guided Carbon-Ion Microporous Radiation to Tumor Hypoxia Area Triggers Robust Abscopal Effects as Open Field Radiation

Qingting Huang; Yun Sun; Weiwei Wang; Lien-Chun Lin; Yangle Huang; Jing Yang; Xiaodong Wu; Lin Kong; Jiade Jay Lu

doi:10.3389/fonc.2020.597702

Biological Guided Carbon-Ion Microporous Radiation to Tumor Hypoxia Area Triggers Robust Abscopal Effects as Open Field Radiation

Front Oncol. 2020 Nov 19:10:597702. doi: 10.3389/fonc.2020.597702. eCollection 2020.

Authors

Qingting Huang^{1

2

3}, Yun Sun^{3

4}, Weiwei Wang^{3

5}, Lien-Chun Lin^{3

5}, Yangle Huang², Jing Yang^{1

3}, Xiaodong Wu^{3

5}, Lin Kong^{2

3}, Jiade Jay Lu^{1

3}

Affiliations

¹ Department of Radiation Oncology, Shanghai Proton and Heavy Ion Center, Shanghai, China.
² Department of Radiation Oncology, Shanghai Proton and Heavy Ion Center, Fudan University Cancer Hospital, Shanghai, China.
³ Shanghai Engineering Research Center of Proton and Heavy Ion Radiation Therapy, Shanghai, China.
⁴ Department of Research and Development, Shanghai Proton and Heavy Ion Center, Shanghai, China.
⁵ Department of Medical Physics, Shanghai Proton and Heavy Ion Center, Shanghai, China.

Abstract

Recently, a growing number of studies focus on partial tumor irradiation to induce the stronger non-target effects. However, the value of partial volume carbon ion radiotherapy (CIRT) targeting hypoxic region of a tumor under imaging guidance as well as its effect of inducing radiation induced abscopal effects (RIAEs) have not been well investigated. Herein, we developed a technique of carbon ion microporous radiation (CI-MPR), guided by ¹⁸F-FMISO PET/computerized tomography (CT), for partial volume radiation targeting the hypoxia area of a tumor and investigated its capability of inducing abscopal effects. Tumor-bearing mice were inoculated subcutaneously with breast cancer 4T1 cells into the flanks of both hind legs of mouse. Mice were assigned to three groups: group I: control group with no treatment; group II: carbon ion open field radiation (CI-OFR group) targeting the entire tumor; group III: partial volume carbon ion microporous radiation (CI-MPR group) targeting the hypoxia region. The tumors on the left hind legs of mice were irradiated with single fraction of 20 Gy of CIRT. Mice treated with CI-MPR or CI-OFR showed that significant growth delay on both the irradiated and unirradiated of tumor as compared to the control groups. Tumor regression of left tumor irradiated with CI-OFR was more prominent as compared to the tumor treated with CI-MPR, while the regression of the unirradiated tumor in both CI-MPR and CI-OFR group was similar. Biological-guided CIRT using the newly developed microporous technique targeting tumor hypoxia region could induce robust abscopal effects similar to CIRT covering the entire tumor.

Keywords: 18F-FMISO PET/computerized tomography; abscopal effect; carbon ion; hypoxia; microporous radiation.