Tumor microenvironment after biodegradable BCNU wafer implantation: special consideration of immune system.

Abstract

Biomaterials to treat cancers hold therapeutic potential; however, their translation to bedside treatment requires further study. The carmustine (1,3-bis (2-chloroethyl)-1-nitrosourea; BCNU) wafer, a biodegradable polymer, currently is the only drug that is able to be placed at the surgical site to treat malignant tumors. However, how this wafer affects the surrounding tumor microenvironment is not well understood to date. We retrospectively reviewed all patients with glioblastoma treated with and without BCNU wafers who underwent repeat resection at tumor recurrence. We investigated radiological imaging; the interval between the two surgeries; and immunohistochemistry of CD3, CD4, CD8, CD20, CD68, FOXP3, and PD1. We implanted BCNU wafers in 41 newly diagnosed glioblastoma patients after approval of the wafer in Japan. Of them, 14 underwent surgery at recurrence and tissue was obtained from around the wafers. The interval between the first and second surgeries ranged from 63 to 421 days. The wafer could be observed on magnetic resonance imaging at up to 226 days, whereas intraoperatively the biodegraded material of the wafer could be found at up to 421 days after the initial surgery. Immunohistochemical analysis demonstrated that CD8+ and CD68+ cells were significantly increased, but FOXP3+ cells did not increase, after wafer implantation compared to tissue from cases without wafer implantation. MRI data and immune cells, as well as interval between surgeries and immune cells, demonstrated positive correlation. These results helped us to understand the bioactivity of bioengineered materials and to establish a new approach for immunotherapy.

• Authors: Ichiyo Shibahara, Mitsuto Hanihara, Takashi Watanabe, Mitsuru Dan, Sumito Sato, Hiroki Kuroda, Akinori Inamura, Madoka Inukai, Atsuko Hara, Yoshie Yasui, Toshihiro Kumabe
• Journal: Journal of neuro-oncology (J Neurooncol) Vol. 137 Issue 2 Pg. 417-427 (Apr 2018) ISSN: 1573-7373 [Electronic] United States
• PMID: 29468445 (Publication Type: Journal Article)

Chemical References

• Antineoplastic Agents, Alkylating
• Biomarkers, Tumor
• Carmustine

Topics

• Absorbable Implants
• Adult
• Aged
• Antineoplastic Agents, Alkylating (administration & dosage)
• Biomarkers, Tumor (immunology)
• Brain (drug effects, immunology, pathology, surgery)
• Brain Neoplasms (diagnostic imaging, drug therapy, immunology, surgery)
• Carmustine (administration & dosage)
• Child
• Female
• Glioblastoma (diagnostic imaging, drug therapy, immunology, surgery)
• Humans
• Immunohistochemistry
• Magnetic Resonance Imaging
• Male
• Middle Aged
• Neoplasm Recurrence, Local (diagnostic imaging, drug therapy, immunology, surgery)
• Retrospective Studies
• Tumor Microenvironment (drug effects, immunology)