Dermaseptin B2’s Anti-Proliferative Activity and down Regulation of Anti-Proliferative, Angiogenic and Metastatic Genes in Rhabdomyosarcoma RD Cells <i>in Vitro</i>

Background: Rhabdomyosarcoma (RMS) is the most prevalent soft tissue sarcoma in children, representing approximately 50% of pediatric sarcomas and can develop in any part of the body though more frequently at the extremities. Aim: Evaluating the in vitro anti-proliferative activity of Dermaseptin B2 on Rhabdomyosarcoma RD (CCL-136TM) cells and its effect on the expression of MYC, FGFR1, NOTCH1, and CXCR7 genes involve in processes including proliferation, angiogenesis and metastasis. Methods: RD cells were grown in Dulbecco’s Modified Eagle’s Medium supplemented with 10% Fetal Bovine Serum. Exponentially growing cells were treated with Dermaseptin B2 and Antiproliferative activity was assayed using the resazurin and migration assays at three time-points. In order to determine the gene expression profiles of MYC, NOTCH1, FGFR1 and CXCR7, total RNA was extracted from the cells and q-RT-PCR was performed with β-Actin as reference gene. Results: Dermaseptin B2 inhibited the proliferation of RD cells in a time and concentration dependent manner as with IC50 values of 7.679 μM, 7.235 μM, 5.993 μM. The 2-dimentional wound healing assay showed inhibition of migration and motility of the RD cells at time-points of 6, 24, 48 and 72-hours with the greatest inhibition observed at 72-hours. Dermaseptin B2 downregulated the target MYC (fc;1.5013, 1.5185, 2.4144), CXCR7 (fc;2.8818, 4.4430, 3.9924), FGFR1 (fc;2.3515, 2.0809, 2.2543), NOTCH1 (fc;2.4667, 4.6274, 4.3352) genes for the three-time points respectively. NOTCH1 and CXCR7 showed higher fold changes with respect to β-Actin than MYC and FGFR1. Conclusion: The results of this study indicate that Dermaseptin B2 is a target molecule for signaling pathways including PI3K/AKT, RTK and NOTCH pathways that could affect the transcription of these genes and overall inhibition of cancer progression. Further studies are needed to give a better understanding of the detailed mechanisms of action as well as the effects of the Dermaseptin B2 peptide in vivo.