The role of irreversible electroporation in promoting M1 macrophage polarization via regulating the HMGB1-RAGE-MAPK axis in pancreatic cancer

Abstract

Irreversible electroporation (IRE) is an effective method for treating pancreatic ductal adenocarcinoma (PDAC). It remains unclear whether IRE can induce a specific immune response by stimulating macrophages. Here, the associated markers of macrophages were analyzed after exposure to tumor culture supernatant (TSN) of tumor cells treated with electroporation. Subcutaneous and orthotopic PDAC models were also used to evaluate the effect of macrophage polarization induced by IRE. Aside from its direct killing effect, IRE could induce the immunogenic cell death of tumor cells by increasing the synthesis and secretion of damage associated molecular patterns. Moreover, IRE could increase the release of HMGB1, which activates the MAPK-p38 pathway and leads to the increased expression of M1 markers in macrophages, through binding to the receptor of the advanced glycation end-product (RAGE) receptor. M1 polarization was inhibited by the inhibitors of HMGB1 release, the RAGE receptor, and the MAPK-p38 signaling pathway, but it was activated by rHMGB1 or the stimulator of MAPK-p38. In addition, the promotion of M1 macrophage polarization was enhanced by the positive-feedback release or expression of HMGB1 and RAGE through the MAPK-ERK pathway in macrophages. The promotion of M1 macrophage polarization induced by IRE provided a specific rationale for the combination of IRE and immune therapy in treating PDAC.

Irreversible Electroporation Plus Anti-PD-1 Antibody versus Irreversible Electroporation Alone for Patients with Locally Advanced Pancreatic Cancer

“… 9 Additionally, IRE could also enhance the process of antigen presentation by promoting M1 macrophage polarization and maturation of dendritic cells. 10 , 19 Based on these findings, a promising approach to improve the responsiveness of ICIs is to utilize the immunogenic properties of IRE to increase the cytotoxic T cells (CTL) to the “cold” TME, switching its immune status to “hot”. The combination of IRE and PD-1 immune checkpoint blockade could significantly promote survival in Kras-induced pancreatic cancer (KPC) mode by selectively promoting the infiltration of CD8 + T cells.…”

“…Thus, apart from inducing apoptosis of tumor cells, IRE can also reconstruct the microenvironment within the tumor and induce the immune response. [9][10][11] Previous studies had shown that IRE could alleviate immune suppression and induce activation of T cells, indicating that IRE may potentiate the antitumor efficacy of immunotherapy in PDAC. 9,12 In recent years, game-changing advances have been achieved in the development of therapies of various cancers, including melanoma, lung and liver cancers with immune checkpoint inhibitors (ICIs).…”

“…35 Simultaneously, more and more studies indicated that IRE could further be an immune-stimulating method other than induce tumor cell death only. 23,36 We previously found that IRE induced local immunomodulation by promoting M1 macrophage polarization and increasing specific T cell infiltration, 9,10 indicating that the active immune status stimulated by IRE and the release of tumor antigen might further enhance the efficacy of immune therapy. Additionally, the low expression of PD-1 could contribute to the low response rates of ICIs, which could be partly reversed by the elevated expression of PD-1 in T cells induced by IRE.…”

The effect of HMGB1 and RAGE on the clinicopathological and prognostic features of prostate cancer

“…Accumulating evidence indicates that the role of HMGB1 extends beyond the nucleus, notably its extracellular role in inflammation [15] . Outside the cell, it can be passively secreted from dying or stressed cells or actively secreted from immune cells, such as activated macrophages, which can function as a danger signal and proinflammatory mediator through interaction with multiple other molecules, including RNA, proteins, lipopolysaccharides, nucleosomes, and several cell surface receptors [e.g., receptor for advanced glycation end product (RAGE), toll-like receptor (TLR) 2, and TLR 4], with RAGE being regarded as a dominant receptor for HMGB1 in tumorigenesis [5,16] . Extracellular HMGB1/RAGE interactions facilitate tumor proliferation via activation of p44/p42, p38, and SAPK/JNK MAPKs [17] .…”

Progress on irreversible electroporation combined with immunotherapy in the treatment of solid tumors

“…淋巴细胞的浸润。Guo 等人 [20] [24][25] ，诱导的巨噬细胞向 M1 型极化 [26] ，脾细胞中 CD8 + T 细胞和记忆 T 细胞比例显著增加 [25] 。此外，经 IRE 处理的肿瘤细胞上清液可抑制肿瘤的生长，且 IRE 诱导 的免疫反应可抑制远隔部位肿瘤生长，表明 IRE 激活的系统性免疫应答具有全身性的抗肿瘤作 用 [25] 。Narayanan 等人 [24] [24] ， 提示检测方法对判断 IRE 介导的肿瘤免疫反应的特点有显著影响。两项临床研究发现 [27][28] IRE [18][19]29] 。(3)多项研究均在 IRE 与其 它疗法联合治疗后对荷瘤机体的免疫细胞亚群进行了检测 [24,30] ，而其它疗法对机体免疫反应影 [31] 。IRE 消融局部肿瘤组织后濒死细胞的可释放大量的内源性危险 信号分子，即损伤相关分子模式 (damage associated molecular patterns, DAMP)，驻留在 肿瘤组织中的 DC 细胞可摄取这些抗原分子并迁移至引流淋巴结并重新激活肿瘤抗原特异 性 T 细胞，影响免疫抑制性 T 细胞亚群的扩增，活化的肿瘤抗原特异性 T 细胞可能归巢到 体内更远的部位消除转移灶，抑制肿瘤的进展 [32][33] 。大量研究表明，IRE 介导的细胞膜穿孔 可增加 DAMP 的合成和分泌，如 ATP、HMGB1、钙网蛋白及 HSP70 等 [25-26, 30, 34] ，诱导肿瘤 细胞的免疫原性细胞死亡，增强抗肿瘤免疫反应 [25] 。且 DAMP 的释放随着电场强度的增加 而增加，其分泌水平与细胞死亡呈正相关 [34] 。He 等人 [26] [13,35] 。Zhao 等人 [30] [36][37] 。胸腺基质淋巴细胞生成素(TSLP)已被证实在多种肿瘤中 可驱动免疫细胞向促癌免疫表型 Th2 型细胞极化 [38][39][40] ，Goswami 等人 [41] [42] ，对于肾癌的消融治疗是安全有效的， 且具备对于小肾癌进行根治性治疗的潜力 [43] ；Distelmaier 等人 [44] 证实了 IRE 可用于邻近门 静脉或肝静脉的肝脏肿瘤的消融治疗，不受热沉效应影响；Blazevski 等人 [45] 综述分析了 IRE 对 283 例前列腺癌患者的治疗效果，分析结果表明 91-100%的患者保留了控尿功能， 79-100%的男性保留了勃起功能，复发率为 0%-33%，提示 IRE 在有效清除肿瘤的同时还可 保障患者的生活质量，是一种极具前景的前列腺癌的治疗方案。 胰腺癌对免疫治疗不敏感与其高度免疫抑制的 TME 密切有关，Yang 等人 [46] 研究发现 [24,30] 。Neill 等人 [47] 研究发现 IRE 消融小鼠原位胰腺癌 残存肿瘤细胞 PD-L1 的表达增加，并进一步采用 IRE 联合纳武单抗(FDA 批准的 PD-1 抑 制剂临床用药)对 10 例 III 期不可手术切除的胰腺癌患者进行治疗，患者疾病进展的平均 时间为 6.3 个月，中...…”