Abstract：
BACKGROUND: Colon adenocarcinoma (COAD) is a prevalent malignant tumor globally, contributing significantly to cancer-related mortality. COAD guidelines label MSI (Microsatellite instability) and MSS (Microsatellite stability) subtypes as global classification criteria and treatment strategy selection criteria for COAD. Various combination therapies involving PD-L1 inhibitors and adjuvant therapy to enhance anti-tumor efficacy.
METHODS: Datasets from single-cell RNA sequencing and bulk RNA sequencing in the TCGA and GEO databases were utilized to identify differentially expressed genes (DEGs). Furthermore, the correlation between ATP8B3 and PD-L1 was validated using siRNA, shRNA, and western blot analysis. Additionally, the association between ATP8B3 and immune checkpoint blockade (ICB) therapy was investigated through immune infiltration analysis and flow cytometry in both in vivo and in vitro assays.
RESULTS: In the COAD patient group, ATP8B3 significantly contributed to the establishment of an immunosuppressive microenvironment. Inhibiting ATP8B3 led to a reduction in PD-L1 expression in colon cancer cell lines. Additionally, ATP8B3 expression levels could serve as a potential guide for PD-L1 treatment in MSI-H COAD patients, with higher ATP8B3 expression associated with increased sensitivity to PD-L1 therapy. However, due to the lack of immuno-killer cells in the microenvironment of MSS subtypes, elevated ATP8B3 expression couldn\'t increase the sensitivity of MSS COAD patients to PD-L1 inhibitors.
CONCLUSIONS: Our research results support that Inhibiting ATP8B3 could enhance TIL (tumor-infiltrating lymphocyte) infiltration by reducing PD-L1 expression in MSI-H COAD, thereby serving as an effective strategy to improve PD-L1 blocker efficacy. The treatment strategy of combining ATP8B3 inhibitors and immunotherapy for MSI/MSS COAD patients will be the best choice.
METHODS: Datasets from single-cell RNA sequencing and bulk RNA sequencing in the TCGA and GEO databases were utilized to identify differentially expressed genes (DEGs). Furthermore, the correlation between ATP8B3 and PD-L1 was validated using siRNA, shRNA, and western blot analysis. Additionally, the association between ATP8B3 and immune checkpoint blockade (ICB) therapy was investigated through immune infiltration analysis and flow cytometry in both in vivo and in vitro assays.
RESULTS: In the COAD patient group, ATP8B3 significantly contributed to the establishment of an immunosuppressive microenvironment. Inhibiting ATP8B3 led to a reduction in PD-L1 expression in colon cancer cell lines. Additionally, ATP8B3 expression levels could serve as a potential guide for PD-L1 treatment in MSI-H COAD patients, with higher ATP8B3 expression associated with increased sensitivity to PD-L1 therapy. However, due to the lack of immuno-killer cells in the microenvironment of MSS subtypes, elevated ATP8B3 expression couldn\'t increase the sensitivity of MSS COAD patients to PD-L1 inhibitors.
CONCLUSIONS: Our research results support that Inhibiting ATP8B3 could enhance TIL (tumor-infiltrating lymphocyte) infiltration by reducing PD-L1 expression in MSI-H COAD, thereby serving as an effective strategy to improve PD-L1 blocker efficacy. The treatment strategy of combining ATP8B3 inhibitors and immunotherapy for MSI/MSS COAD patients will be the best choice.
摘要：
背景：结肠腺癌（COAD）是全球普遍存在的恶性肿瘤，对癌症相关死亡率有显著影响。COAD指南将MSI（微卫星不稳定性）和MSS（微卫星稳定性）亚型标记为COAD的全球分类标准和治疗策略选择标准。涉及PD-L1抑制剂和辅助疗法的各种组合疗法以增强抗肿瘤功效。
方法：利用TCGA和GEO数据库中单细胞RNA测序和批量RNA测序的数据集来鉴定差异表达基因(DEGs)。此外，使用siRNA验证ATP8B3和PD-L1之间的相关性，shRNA,和蛋白质印迹分析。此外,在体内和体外试验中,通过免疫浸润分析和流式细胞术研究了ATP8B3与免疫检查点阻断(ICB)治疗之间的关联.
结果：在COAD患者组中，ATP8B3显著有助于建立免疫抑制微环境。抑制ATP8B3导致结肠癌细胞系中PD-L1表达减少。此外,ATP8B3表达水平可作为MSI-HCOAD患者PD-L1治疗的潜在指导，更高的ATP8B3表达与PD-L1治疗敏感性增加相关。然而,由于MSS亚型微环境中缺乏免疫杀伤细胞，升高的ATP8B3表达不能增加MSSCOAD患者对PD-L1抑制剂的敏感性。
结论：我们的研究结果支持抑制ATP8B3可以通过减少MSI-HCOAD中的PD-L1表达来增强TIL（肿瘤浸润淋巴细胞）浸润，从而作为提高PD-L1阻滞剂疗效的有效策略。MSI/MSSCOAD患者联合ATP8B3抑制剂和免疫治疗的治疗策略将是最佳选择。
方法：利用TCGA和GEO数据库中单细胞RNA测序和批量RNA测序的数据集来鉴定差异表达基因(DEGs)。此外，使用siRNA验证ATP8B3和PD-L1之间的相关性，shRNA,和蛋白质印迹分析。此外,在体内和体外试验中,通过免疫浸润分析和流式细胞术研究了ATP8B3与免疫检查点阻断(ICB)治疗之间的关联.
结果：在COAD患者组中，ATP8B3显著有助于建立免疫抑制微环境。抑制ATP8B3导致结肠癌细胞系中PD-L1表达减少。此外,ATP8B3表达水平可作为MSI-HCOAD患者PD-L1治疗的潜在指导，更高的ATP8B3表达与PD-L1治疗敏感性增加相关。然而,由于MSS亚型微环境中缺乏免疫杀伤细胞，升高的ATP8B3表达不能增加MSSCOAD患者对PD-L1抑制剂的敏感性。
结论：我们的研究结果支持抑制ATP8B3可以通过减少MSI-HCOAD中的PD-L1表达来增强TIL（肿瘤浸润淋巴细胞）浸润，从而作为提高PD-L1阻滞剂疗效的有效策略。MSI/MSSCOAD患者联合ATP8B3抑制剂和免疫治疗的治疗策略将是最佳选择。
