Purification and In Vitro and In Vivo Expression Mechanism of Anti-Tumor Substances from Amphibians

Amphibians produce diverse bioactive compounds with reported antimicrobial and cytotoxic activities, yet their potential as anticancer agents remains underexplored. This study evaluated the antitumor efficacy of amphibian-derived skin extracts in a xenograft model. Sixty animals were randomly allocated to treatment or control groups and monitored for 12 weeks. Tumor progression was assessed by volumetric and gravimetric endpoints, while mechanistic insights were obtained through Ki-67 immunohistochemistry, TUNEL apoptosis assays, and quantitative RT-PCR profiling of p53, Bax, Bcl-2, Caspase-3, and Ki-67. Treated animals developed significantly smaller tumors compared with controls, with reduced volume (120.5 ± 3.8 mm³ vs. 180.2 ± 4.3 mm³; p = 0.005) and mass (0.62 ± 0.08 g vs. 0.93 ± 0.09 g; p = 0.005). Histological analyses revealed a lower proliferation index (25.5% vs. 40.3%) and a higher apoptotic index (35.0% vs. 19.0%), both of which were statistically significant. At the molecular level, expression profiling revealed the upregulation of p53, Bax, and Caspase-3, accompanied by the downregulation of Bcl-2 and Ki-67, which aligns with the observed tissue phenotypes. Taken together, these results provide convergent evidence that amphibian-derived extracts exert multifaceted antitumor effects, inhibiting proliferation and promoting apoptosis. Although further studies are required to characterize active constituents, establish pharmacological profiles, and validate efficacy in mammalian models, the findings support amphibian-origin compounds as promising candidates for preclinical anticancer development.

两栖动物可产生多种兼具抗菌与细胞毒活性的生物活性化合物，但其作为抗癌制剂的潜力仍未得到充分挖掘。本研究在异种移植模型中评估了两栖动物皮肤提取物的抗肿瘤功效。将60只实验动物随机分为给药组与对照组，连续监测12周。本研究通过体积与重量指标评估肿瘤进展情况，并通过Ki-67免疫组化（Ki-67 immunohistochemistry）、TUNEL细胞凋亡检测（TUNEL apoptosis assays），以及针对p53基因（p53）、Bax蛋白（Bax）、Bcl-2蛋白（Bcl-2）、Caspase-3蛋白（Caspase-3）与Ki-67的实时定量逆转录聚合酶链反应（quantitative RT-PCR）分析，获取相关机制信息。与对照组相比，给药组动物的肿瘤负荷显著更低：肿瘤体积为(120.5 ± 3.8) mm³，对照组为(180.2 ± 4.3) mm³（p=0.005）；肿瘤重量为(0.62 ± 0.08) g，对照组为(0.93 ± 0.09) g（p=0.005）。组织学分析显示，给药组的细胞增殖指数更低（25.5% vs. 40.3%），细胞凋亡指数更高（35.0% vs. 19.0%），两项指标均具有统计学显著性。在分子层面，表达谱分析显示p53基因（p53）、Bax蛋白（Bax）与Caspase-3蛋白（Caspase-3）的表达上调，而Bcl-2蛋白（Bcl-2）与Ki-67的表达下调，该结果与观测到的组织表型一致。综上，本研究结果提供了一致性证据，表明两栖动物来源的提取物可发挥多维度抗肿瘤作用，即抑制肿瘤细胞增殖并诱导细胞凋亡。尽管后续仍需开展研究以明确其活性成分、建立药理学特征，并在哺乳动物模型中验证其抗肿瘤功效，但本研究结果表明，两栖动物来源的化合物有望成为抗癌临床前开发的潜在候选药物。