Biology subjects

Sanchez-Zarzalejo, C.

Publications and source records attributed to Sanchez-Zarzalejo, C..

4 recordsLinked to original sources

bioRxiv2025

Oligomerization enables the selective targeting of intrinsically disordered regions by small molecules

Intrinsically disordered regions (IDRs) are challenging drug targets because they lack stable interaction sites for drug-like molecules. We studied the first small molecule targeting an IDR to be evaluated in a clinical trial and found that it interacts selectively with an oligomeric form of the protein, more structured than the monomeric state, that is stabilized by interactions involving aromatic residues in regions with helical propensity. We also found that this compound alters the network of interactions defining the conformational ensemble of its target, thus affecting its condensation properties, linked to its function as a transcription factor. These findings provide a framework for developing strategies to target intrinsically disordered regions with small molecules.

biophysics↗

bioRxiv2024

Targeted KRAS(G12V) degradation elicits efficient and durable lung adenocarcinoma regression in vivo

Recent drug discovery breakthroughs led to the approval of KRASG12C inhibitors in lung adenocarcinoma (LUAD). Unfortunately, clinical responses remain limited due to rapid resistance onset. Proteolysis-targeting chimeras (PROTACs) have emerged as promising alternatives to traditional inhibition. However, there is limited mechanistic understanding of KRAS degradation in vivo. Here, we developed a preclinical LUAD mouse model and demonstrated that targeted oncogenic KRAS degradation induces rapid tumor regression. Transcriptional, histological, and immunophenotypic analyses revealed a substantial remodeling of the tumor microenvironment. Notably, disease relapse observed during long-term degrader treatment stems from proteolysis machinery dysregulation, indicating resistance mechanisms distinct from those reported upon KRAS inhibition. Our findings highlight the therapeutic potential of KRAS degradation in LUAD, offering insights into cell-intrinsic and extrinsic mechanisms driving durable antitumor responses and supporting further clinical exploration. SIGNIFICANCEGiven the short duration of the clinical responses to KRAS inhibitors, complementary therapies are a dire medical need. Our preclinical findings endorse KRAS degradation as a therapeutic alternative in LUAD, where cell-intrinsic and extrinsic mechanisms drive tumor regression and durable therapeutic responses.

cancer biology↗

bioRxiv2024

HYL001, a new potent TGFβ signaling inhibitor that is efficacious against microsatellite stable CRC metastasis in combination with immune checkpoint therapy in mice

Blockade of the TGF{beta} signalling pathway has emerged from preclinical studies as a potential treatment to enhance the efficacy of immune checkpoint inhibition in advanced colorectal cancer (CRC) and several other types of cancer. However, clinical translation of first-generation inhibitors has known little success. Here, we report the synthesis and characterization of HYL001, a potent inhibitor of TGF{beta} receptor 1 (ALK5), that is approximately 9 times more efficacious than the structurally related compound galunisertib, while maintaining a favourable safety profile. HYL001 in combination with immune checkpoint blockade (anti-PD1) eradicates liver metastases generated in mice by microsatellite stable, aggressive colorectal cancer tumours at doses where galunisertib is ineffective. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=156 SRC="FIGDIR/small/593510v1_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@1909963org.highwire.dtl.DTLVardef@4644d2org.highwire.dtl.DTLVardef@1506d80org.highwire.dtl.DTLVardef@14504b7_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗

bioRxiv2022

Androgen receptor condensates as drug targets

Transcription factors are among the most attractive therapeutic targets but are considered largely undruggable due to the intrinsically disordered nature of their activation domains. Here we show that the aromatic character of the activation domain of the androgen receptor, a therapeutic target for castration resistant prostate cancer, is key for its activity as a transcription factor by allowing it to partition into transcriptional condensates. Based on this knowledge we optimized the structure of a small molecule inhibitor, previously identified by phenotypic screening, that targets a specific transactivation unit within the domain that is partially folded and rich in aromatic residues. The optimized compounds had more affinity for their target, inhibited androgen receptor-dependent transcriptional programs, and had antitumorigenic effect in models of castration-resistant prostate cancer in cells and in vivo. These results establish a generalizable framework to target small molecules to the activation domains of oncogenic transcription factors and other disease-associated proteins with therapeutic intent.

biochemistry↗