Biology subjects

Cardenas, E. L.

Publications and source records attributed to Cardenas, E. L..

3 recordsLinked to original sources

bioRxiv2025

SHAPE-based chemical probes for studying preQ1-RNA interactions in living bacteria

Interrogating RNA-small molecule interactions inside cells is critical for advancing RNA-targeted drug discovery. In particular, chemical probing technologies that both identify small molecule-bound RNAs and define their binding sites in the complex cellular environment will be key for establishing the on-target activity necessary for successful hit-to-lead campaigns. Using the small molecule metabolite preQ1 and its cognate riboswitch RNA as a model, herein we describe a chemical probing strategy for filling this technological gap. Building on well-established RNA acylation chemistry employed by in vivo click selective 2'-hydroxyl acylation analyzed by primer extension (icSHAPE) probes, we developed an icSHAPE-based preQ1 probe that retains biological activity in a preQ1 riboswitch reporter assay and successfully enriches the preQ1 riboswitch from living bacterial cells. Further, we map the preQ1 binding site on probe-modified riboswitch RNA by mutational profiling (MaP). As the need for rapid profiling of on- and off-target small molecule interactions continues to grow, this chemical probing strategy offers a method to interrogate cellular RNA-small molecule interactions and support the future development of RNA-targeted therapeutics.

biochemistry↗

bioRxiv2024

Second-Generation Cap Analogue Prodrugs for Targeting Aberrant Eukaryotic Translation Initiation Factor 4E (eIF4E) Activity in Drug-Resistant Melanoma

Melanoma is the deadliest form of skin cancer with a 5-year survival rate of less than 20%. While significant strides have been made in the field of kinase-targeted and immune-based therapies for melanoma, the development of resistance to these therapeutic agents has hindered the success of treatment. Drug-resistant melanoma is particularly reliant on enhanced cap-dependent translation to drive the production of oncoproteins that promote growth and survival. The m7GpppX cap-binding protein eukaryotic translation initiation factor 4E (eIF4E) is the rate-limiting factor of cap-dependent translation initiation, and its overexpression in melanoma tumors has been shown to drive resistance to BRAFV600E kinase-targeted inhibitors. These findings point to eIF4E-targeted therapies as a promising strategy to overcome drug resistance in melanoma. Herein, we build upon our previous work of developing cell-permeable cap analogue inhibitors to design second-generation cap analogues that inhibit eIF4E-mediated cap-dependent translation in drug-resistant melanoma cells.

cancer biology↗

bioRxiv2023

Design of Cell-Permeable Inhibitors of Eukaryotic Translation Initiation Factor 4E (eIF4E) for Inhibiting Aberrant Cap-Dependent Translation in Cancer

Eukaryotic translation initiation factor 4E (eIF4E) is an RNA-binding protein that binds to the m7GpppX-cap at the 5' terminus of coding mRNAs to initiate cap-dependent translation. While all cells require cap-dependent translation, cancer cells become addicted to enhanced translational capacity, driving the production of oncogenic proteins involved in proliferation, evasion of apoptosis, metastasis, and angiogenesis among other cancerous phenotypes. eIF4E is the rate-limiting translation factor and its activation has been shown to drive cancer initiation, progression, metastasis, and drug resistance. These findings have established eIF4E as a translational oncogene and promising, albeit challenging, anti-cancer therapeutic target. Although significant effort has been put forth towards inhibiting eIF4E, the design of cell-permeable, cap-competitive inhibitors remains a challenge. Herein, we describe our work towards solving this long-standing challenge. By employing an acyclic nucleoside phosphonate prodrug strategy, we report the synthesis of cell-permeable inhibitors of eIF4E binding to capped mRNA to inhibit cap-dependent translation.

cancer biology↗