CASP3 and obstructive sleep apnea syndrome: In the present study, we found that treatment with the combination of carbon-ion beam irradiation and ZOL, a third-generation bisphosphonate, notably decreased OSA cell viability and survival, with a greater extent of DNA fragmentation, higher caspase 3 activity, higher cleaved caspase 3 and cleaved PARP levels, and lower Bcl-2 and nuclear factor (NF)-κB expression levels than that caused by treatment with carbon-ion beam irradiation alone or X-ray irradiation combined with ZOL.