Deoxyarbutin targets mitochondria to trigger p53-dependent senescence of glioblastoma cells.

Cellular senescence is a natural barrier of the transition from premalignant cells to invasive cancer. Pharmacological induction of senescence has been proposed as a possible anticancer strategy. In this study, we found that deoxyarbutin inhibited the growth of glioblastoma (GBM) cells by inducing cellular senescence, independent of tyrosinase expression. Instead, deoxyarbutin induced mitochondrial oxidative stress and damage. These aberrant mitochondria were key to the p53-dependent senescence of GBM cells. Facilitating autophagy or mitigating mitochondrial oxidative stress both suppressed p53 expression and alleviated cellular senescence induced by deoxyarbutin. Thus, our study reveals that deoxyarbutin induces mitochondrial oxidative stress to trigger the p53-dependent senescence of GBM cells. Importantly, deoxyarbutin treatment resulted in accumulation of p53, induction of cellular senescence, and inhibition of tumor growth in a subcutaneous tumor model of mouse. In conclusion, our study reveals that deoxyarbutin has therapeutic potential for GBM by inducing mitochondrial oxidative stress for p53-dependent senescence of GBM cells.