Rashid Khalid, Röder Christian, Goumas Freya, Egberts Jan-Hendrik, Kalthoff Holger
Institute for Experimental Cancer Research, University Medical Centre Schleswig-Holstein (UKSH), Campus Kiel, 24105 Kiel, Germany.
Department of General, Visceral-, Thoracic-, Transplantation- and Paediatric Surgery, University Medical Centre Schleswig-Holstein (UKSH), Campus Kiel, 24105 Kiel, Germany.
Cancers (Basel). 2021 Oct 30;13(21):5458. doi: 10.3390/cancers13215458.
Despite the potential apoptotic functions, the CD95/CD95L system can stimulate survival as well as pro-inflammatory signaling, particularly through the activation of NFκB. This holds true for the TNF/TNFR and the TRAIL/TRAILR systems. Thus, signaling pathways of these three death ligands converge, yet the specific impact of the CD95/CD95L system in this crosstalk has not been well studied. In this study, we show that gemcitabine stimulates the expression of pro-inflammatory cytokines, such as IL6 and IL8, under the influence of the CD95/CD95L system and the pharmacological inhibitor, sCD95Fc, substantially reduced the expression in two PDAC cell lines, PancTuI-luc and A818-4. The stem cell phenotype was reduced when induced upon gemcitabine as well by sCD95Fc. Moreover, TNF-α as well as TRAIL up-regulate the expression of CD95 and CD95L in both cell lines. Conversely, we detected a significant inhibitory effect of sCD95Fc on the expression of both IL8 and IL6 induced upon TNF-α and TRAIL stimulation. In vivo, CD95L inhibition reduced xeno-transplanted recurrent PDAC growth. Thus, our findings indicate that inhibition of CD95 signaling altered the chemotherapeutic effects of gemcitabine, not only by suppressing the pro-inflammatory responses that arose from the CD95L-positive tumor cells but also from the TNF-α and TRAIL signaling in a bi-lateral crosstalk manner.
尽管CD95/CD95L系统具有潜在的凋亡功能,但它也能刺激细胞存活以及促炎信号传导,特别是通过激活核因子κB来实现。TNF/TNFR系统和TRAIL/TRAILR系统也是如此。因此,这三种死亡配体的信号通路相互汇聚,然而CD95/CD95L系统在这种相互作用中的具体影响尚未得到充分研究。在本研究中,我们发现吉西他滨在CD95/CD95L系统的影响下刺激促炎细胞因子如IL6和IL8的表达,而药理抑制剂sCD95Fc在两种胰腺导管腺癌(PDAC)细胞系PancTuI-luc和A818-4中显著降低了其表达。当用吉西他滨诱导时,干细胞表型也因sCD95Fc而降低。此外,TNF-α以及TRAIL在两种细胞系中均上调CD95和CD95L的表达。相反,我们检测到sCD95Fc对TNF-α和TRAIL刺激诱导的IL8和IL6表达具有显著抑制作用。在体内,CD95L抑制减少了异种移植的复发性PDAC的生长。因此,我们的研究结果表明,抑制CD95信号不仅通过抑制CD95L阳性肿瘤细胞产生的促炎反应,而且通过双边相互作用方式抑制TNF-α和TRAIL信号,从而改变了吉西他滨的化疗效果。