Abstract 3210: Photothermal therapy of malignant mesothelioma with delaminated MXene Ti3C2
Authors: Zhou Lanlan , Meng Fayan , Anasori Babak , Gogotsi Yury , El-Deiry Wafik S. 
Published: August 2018

Abstract
Malignant mesothelioma is an aggressive and deadly form of cancer that develops in the thin layer of tissue surrounding the majority of internal organs (mesothelium). Malignant mesothelioma has no known cure and has a very poor prognosis because of late diagnosis and limited usefulness of standard treatments. We are exploring newer treatments to tackle this deadly disease. Photothermal therapy is an emerging noninvasive spatiotemporal selective therapeutic strategy that employs near-infrared photoabsorbers to generate heat for thermal ablation of cancer cells. The therapeutic efficacy of photothermal therapy significantly depends on the transformation of light to sufficient heat with photothermal agents. MXene Ti3C2 is an effective two-dimensional light-to-heat conversion material. The internal light-to-heat conversion efficiency of MXene Ti3C2 was measured to be 100%, indicating a perfect energy conversion. In this study we report for the first time using the MXene Ti3C2 nanoplatform as a photothermal agent to efficiently ablate malignant mesothelioma. First, we prepared two-dimensional MXene Ti3C2 and UV-vis-NIR spectrum showed Ti3C2 has a strong absorbance at the region of 790 nm, which showed a high light extinction coefficient of 26.081 L g-1cm-1 and exhibited a good photothermal conversion efficiency of 22%. Photothermal heating curves show temperatures of different concentration of MXene Ti3C2 increase steadily with irradiation of 808nm laser. Recycling heating profiles demonstrate that MXene Ti3C2 can be repeatedly heated stably. Next, the effects of MXene Ti3C2 on normal and mesothelioma cell lines were tested with CellTiter-Glo® luminescent cell viability assays. MXene Ti3C2 has no toxicity to cells at the tested concentration range. Light microscopy revealed that MXene Ti3C2 can accumulate inside of mesothelioma cells but not in normal cells. There was no red blood cell hemolysis within the tested concentration range and the hemolysis ratio was 0.5% even at ten times higher than the test concentration. Then, normal and mesothelioma cells were treated with and without MXene Ti3C2 for 24~48 hours followed by laser irradiation. CellTiter-Glo® luminescent cell viability assays and colony formation assays validated that MXene Ti3C2-treated mesothelioma cells were eliminated by laser irradiation while normal cells and nontreated mesothelioma were spared. Flow cytometry and Western blot analysis were used for determination of apoptosis. Lastly, we established a mesothelioma mouse xenograft model to evaluate the therapeutic effect of MXene Ti3C2 on mesothelioma in vivo. We are also pursuing the combination of MXene Ti3C2-based photothermal therapy and current therapies for mesothelioma. Our results indicate that MXene Ti3C2 is a promising photothermal agent in therapy of mesothelioma.
Citation Format: Lanlan Zhou, Fayan Meng, Babak Anasori, Yury Gogotsi, Wafik S. El-Deiry. Photothermal therapy of malignant mesothelioma with delaminated MXene Ti3C2 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3210.