Marine natural compound cyclo(L-leucyl-L-prolyl) peptide inhibits migration of triple negative breast cancer cells by disrupting interaction of CD151 and EGFR signaling

Cyclo (L-Leucyl-L-Prolyl) peptide/CLP is a marine natural metabolite and well recognized as an antimicrobial and antioxidant agent with limited studies on anticancer activity. The current study aims to determine the effect of CLP on migration and growth of triple negative breast cancer cell lines. The anti-growth potential was evaluated by MTT, BrdU and TUNEL assays; DNA damage by γH2AX and Dead green assays; antimigration activity by Boyden chamber invasion and wound healing assays. Interaction of CLP with CD151 was resolved by PatchDock. Effect of CLP on the expression of transmembrane CD151 was evaluated by cell-based ELISA assay. The interaction between CD151 and EGFR was predicted by using FireDoc Web server. Impact of CLP on the interaction of CD151 with EGFR was evaluated by co-immunoprecipitation assay. The effect of CLP on the cell cycle and its controlling proteins was determined by Western blotting. CLP reduced the viability of MDA-MB-231 and MDA-MB-468 TNBC cell lines but not human breast healthy epithelial cell line (MCF-12A) similar to eribulin, standard. CLP also inhibited proliferation; cell cycle and migration. It induced DNA strand breaks, DNA damage, and cell death. It showed the most favorable interactions with CD151 in in silico docking and significantly reduced the expression of membrane-bound CD151 proteins. FireDoc Web study predicted the association between CD151 and EGFR with -29.13 kcal/mol of binding energy. CLP reduced the interaction of CD151 with EGFR along with the expression of cyclin D, CDK4, PAK, RAC1, and P27kiP1. This study concludes that CLP suppresses growth and migration by attenuating cell cycle of TNBC cell lines via EGFR and CD151 signaling. Thus, exploring the EGFR and CD151 signaling pathway targeted by CLP may provide a new approach in the treatment of TNBC.

Current Perspectives of Exosomes as Therapeutic Targets and Drug Delivery Vehicles for Pancreatic Cancer

The ever-growing interest in exosomes research is mainly due to their potential applications in health and disease, especially in therapy and diagnosis. To explore the applications of exosomes in the clinical setting, we must understand their characteristics at the molecular levels. Furthermore, exosomes are cell and function specific; therefore, we must ascertain the molecular mechanisms of their biogenesis, cellular recognition, and uptake. In the recent past, engineered exosomes and exosome mimetics have been the subject of active research. However, critical facets of the biology of engineered exosomes and exosome mimetics remain unknown. This review presents our current understanding of the potential role of engineered exosomes and exosome mimetics in diagnosis, prognosis, monitoring of treatment, as well as drug delivery. We also present recent updates on the exosome signature, its role in pancreatic cancer progression, and applications in the delivery of natural therapeutics and RNAi molecules and in the immune response. Lastly, we discuss future prospects and challenges of exosomes in translational studies.