After the subject has completed at least 2 courses of treatment with Serenixol and R-GemOx for up to 6 courses, the patients who have reached ≥ partial remission (PR) and meet the conditions of transplantation can receive transplantation according to the institutional standards, and those who are not suitable for transplantation can receive maintenance treatment with Serenixol. In the maintenance treatment, the dose of Serenixol is 60 mg on the first day of the week until the disease progresses In case of intolerable toxicity or if the researcher believes that the patient is no longer suitable for study treatment, re-examine every 3 months in the first year, the second year and every 6 months after the end of transplantation or maintenance treatment; Patients with stable disease (SD) or disease progression (PD) after 2~6 courses of treatment will end the trial, and no survival follow-up will be conducted
The goal of this interventional study is to evaluate efficiency and safety in prior one-line treated diffuse large B-cell lymphoma. The main questions it aims to answer are:~Complete remission rate~Objective remission rate~Progression-free survival~tolerance Participants will recevied a minimum of 2 and a maximum of 6 cycles of R-GemOx(rituximab 375 mg/m2 IV on day 1 , Gemcitabine 1000 mg/m2, Oxaliplatin 100 mg/m2 IV on day 2) and 60 mg selinexor on days 1, 8, and 15 of each cycle