Boron neutron capture therapy (BNCT) can potentially deliver high linear energy transfer particles to
tumor cells without causing severe damage to surrounding normal tissue, and may thus be beneficial for cases with characteristics of infiltrative growth, which need a wider irradiation field, such as
glioblastoma multiforme.
Hypoxia is an important factor contributing to resistance to anticancer
therapies such as
radiotherapy and
chemotherapy. In this study, we investigated the impact of
oxygen status on 10B uptake in
glioblastoma cells in vitro in order to evaluate the potential impact of local
hypoxia on BNCT. T98G and A172
glioblastoma cells were used in the present study, and we examined the influence of
oxygen concentration on cell viability,
mRNA expression of L-
amino acid transporter 1 (LAT1), and the uptake amount of 10B-BPA. T98G and A172
glioblastoma cells became quiescent after 72 h under 1%
hypoxia but remained viable. Uptake of 10B-BPA, which is one of the agents for BNCT in clinical use, decreased linearly as
oxygen levels were reduced from 20% through to 10%, 3% and 1%.
Hypoxia with <10% O2 significantly decreased
mRNA expression of LAT1 in both cell lines, indicating that reduced uptake of 10B-BPA in
glioblastoma in hypoxic conditions may be due to reduced expression of this important transporter
protein.
Hypoxia inhibits 10B-BPA uptake in
glioblastoma cells in a linear fashion, meaning that approaches to overcoming local tumor hypoxia may be an effective method of improving the success of BNCT treatment.