Cancer stem cells (CSCs) are resistant to anti-tumour therapies and are associated with metastasis and recurrence. High concentrations of lactic acid can promote the maintenance of tumour cell stemness.1 We previously reported that SOX2 promotes the malignant phenotype and stemness of ECCs and ECSC.2 SP1 is a transcription factor. It promotes the proliferation and invasion of endometrial cancer (EC) cells.3 In lung adenocarcinoma, SP1 promotes stemness by modulating the expression of key stemness genes, including OCT4, Nanog, and CTGF.4 Immunotherapy represents a potential treatment option for patients with advanced EC. However, only a limited number of patients benefit from the currently available regimens. Studies have shown that the TGF-β/PD-L1 bispecific antibody can enhance anti-tumor immunity,5 which provides new insights for the treatment of endometrial cancer.