Department of General Surgery, Division of Visceral Surgery, Medical University of Vienna, Vienna, Austria.
Ludwig Boltzmann Institute Applied Diagnostics, Medical University of Vienna, Vienna, Austria.
J Immunother Cancer. 2024 Nov 4;12(11):e009494. doi: 10.1136/jitc-2024-009494.
Patient-derived colorectal cancer (CRC) organoids (PDOs) solely consisting of malignant cells led to major advances in the understanding of cancer treatments. Yet, a major limitation is the absence of cells from the tumor microenvironment, thereby prohibiting potential investigation of treatment responses on immune and structural cells. Currently there are sparse reports describing the interaction of PDOs, cancer-associated fibroblasts (CAFs) and tumor-associated macrophages (TAMs) in complex primary co-culture assay systems.
Primary PDOs and patient matched CAF cultures were generated from surgical resections. Co-culture systems of PDOs, CAFs and monocytic myeloid cells were set up to recapitulate features seen in patient tumors. Single-cell transcriptomics and flow cytometry was used to show effects of culture systems on TAM populations in the co-culture assays under chemotherapeutic and oncolytic viral treatment.
In contrast to co-cultures of tumor cells and monocytes, CAF/monocyte co-cultures and CAF/monocyte/tumor cell triple cultures resulted in a partial differentiation into macrophages and a phenotypic switch, characterized by the expression of major immunosuppressive markers comparable to TAMs in CRC. Oxaliplatin and 5-fluorouracil, the standard-of-care chemotherapy for CRC, induced polarization of macrophages to a pro-inflammatory phenotype comparable to the immunogenic effects of treatment with an oncolytic virus. Monitoring phagocytosis as a functional proxy to macrophage activation and subsequent onset of an immune response, revealed that chemotherapy-induced cell death, but not virus-mediated cell death, is necessary to induce phagocytosis of CRC cells. Moreover, CAFs enhanced the phagocytic activity in chemotherapy treated CRC triple cultures.
Primary CAF-containing triple cultures successfully model TAM-like phenotypes and allow the assessment of their functional and phenotypic changes in response to treatments following a precision medicine approach.
仅由恶性细胞组成的患者衍生结直肠癌（CRC）类器官（PDO）在理解癌症治疗方面取得了重大进展。然而，一个主要的限制是缺乏肿瘤微环境中的细胞，从而禁止对免疫和结构细胞的治疗反应进行潜在的研究。目前，很少有报道描述 PDO 与癌症相关成纤维细胞（CAF）和肿瘤相关巨噬细胞（TAM）在复杂的原发性共培养分析系统中的相互作用。
从手术切除物中生成原发性 PDO 和患者匹配的 CAF 培养物。建立 PDO、CAF 和单核细胞髓样细胞的共培养系统，以重现患者肿瘤中观察到的特征。单细胞转录组学和流式细胞术用于显示培养系统对共培养分析中 TAM 群体的影响，包括化疗和溶瘤病毒治疗。
与肿瘤细胞和单核细胞的共培养相比，CAF/单核细胞共培养和 CAF/单核细胞/肿瘤细胞三重培养导致部分分化为巨噬细胞，并发生表型转换，其特征是表达主要免疫抑制标志物，与 CRC 中的 TAM 相当。奥沙利铂和 5-氟尿嘧啶是 CRC 的标准化疗药物，诱导巨噬细胞向促炎表型极化，与溶瘤病毒治疗的免疫原性效应相当。监测吞噬作用作为巨噬细胞激活的功能替代物和随后发生免疫反应的指标，表明化疗诱导的细胞死亡，但不是病毒介导的细胞死亡，是诱导 CRC 细胞吞噬所必需的。此外，CAF 增强了化疗处理的 CRC 三重培养物中的吞噬活性。
原发性含 CAF 的三重培养物成功模拟了 TAM 样表型，并允许根据精准医学方法评估它们对治疗的功能和表型变化。
