Abstract：
The current work demonstrates the synthesis and characterization of piperic acid conjugates with homochiral/heterochiral dipeptides containing phenylalanine as anti-skin cancer agents. The conjugates PA-DPhe-LPhe-OH, FC-1; PA-LPhe-DPhe-OH, FC-2; PA-DPhe-DPhe-OH, FC-3; and PA-DPhe-DPhe-OH, FC-4 were synthesized, characterized and assessed for cytotoxicity against melanoma cell lines of human and murine origin. Among all, PA-DPhe-DPhe-OH (FC-3) conjugate was identified as a potential cytotoxic lead against melanoma cells by delineating the anti-proliferative and anti-migratory potential together with its anti-inflammatory potential against pro-inflammatory interleukins (IL-1β, IL-6, and IL-8). Evidences from western blotting, fractionation, and immunocytochemistry experiments suggest that Stat-3 is a critical signaling molecule involved in the FC-3 mechanism of action. The results denote that FC-3 profoundly ablates Stat-3 expression, phosphorylation, and nuclear translocation. Stat-3 mRNA analysis revealed that FC-3 did not alter the transcription of Stat-3. However, in cells where proteasome mediated degradation was inhibited, FC-3 failed to check the Stat-3 expression implying that FC-3 augments the proteasomal degradation of Stat-3. Of note, FC-3 failed to reverse the IL-6 mediated hyperactivation of Stat-3 in A375 cells. Critically, in Stat-3 deficient cancer cells, the anti-clonogenic and anti-migratory potential of FC-3 was significantly subdued. Further, the in vivo efficacy of FC-3 was validated in the two-step (DMBA/TPA) chemically induced mouse skin cancer model. The FC-3-treated cohorts of mice unveiled a significant decrease in the cumulative number of tumors besides attenuation of tumor growth with respect to the vehicle-treated mice. Lastly, in corroboration with our in vitro findings, serum collected from mice groups at various intervals during the treatment regimen demonstrated decrement in IL-1β and IL-6 levels in FC-3 treated groups compared to the vehicle-treated group.
摘要：
目前的工作证明了与含有苯丙氨酸的同手性/异手性二肽作为抗皮肤癌剂的胡椒酸缀合物的合成和表征。偶联物PA-DPhe-LPhe-OH,FC-1;PA-LPhe-DPhe-OH,FC-2;PA-DPhe-DPhe-OH,FC-3；和PA-DPhe-DPhe-OH，合成了FC-4，表征并评估了对人和鼠来源的黑色素瘤细胞系的细胞毒性。其中,PA-DPhe-DPhe（FC-3）缀合物通过描述抗增殖和抗迁移潜力及其对促炎白细胞介素的抗炎潜力而被鉴定为针对黑色素瘤细胞的潜在细胞毒性线索（IL-1β，IL-6和IL-8)。来自西方印迹的证据，分级分离和免疫细胞化学实验表明，Stat-3是参与FC-3作用机制的关键信号分子。结果表明，FC-3严重消融了Stat-3的表达，磷酸化和核易位。Stat-3mRNA分析显示FC-3不改变Stat-3的转录。然而,在蛋白酶体介导的降解被抑制的细胞中，FC-3未能检查Stat-3的表达，这意味着FC-3增强了Stat-3的蛋白酶体变性。值得注意的是，FC-3未能逆转IL-6介导的A375细胞中Stat-3的过度活化。严重的,在缺乏Stat-3的癌细胞中，FC-3的抗结瘤和抗迁移潜力显着减弱。Further,FC-3的体内功效在两步法(DMBA/TPA)化学诱导小鼠皮肤癌模型中得到验证.FC-3处理的小鼠组揭示了相对于媒介物处理的小鼠,除了肿瘤生长的减弱之外,肿瘤的累积数量显著减少。最后,我们在体外的发现证实了这一点,在治疗方案期间以不同间隔从小鼠组收集的血清表明,与媒介物治疗组相比,FC-3治疗组的IL-1β和IL-6水平下降。
