Journal: Pharmaceutical Science Advances

Article Title: Unleashing the power of DNA-encoded libraries for challenging targets in drug discovery

doi: 10.1016/j.pscia.2026.100115

Figure Lengend Snippet: Ligands targeting the GTPase KRAS G12C .

Article Snippet: In February 2025, Amgen reported a KRAS G12C covalent inhibitor.

Techniques:

Journal: Cell reports

Article Title: Mutant KRAS-driven selective mRNA translation reveals mechanisms and therapeutic vulnerabilities in cancer

doi: 10.1016/j.celrep.2026.117520

Figure Lengend Snippet: (A) Schematic of ribosome footprinting strategy from MiaPaca-2 (KRAS G12C) or Panc10.05 (KRAS G12D) cells treated with 10 μM sotorasib or MRTX1133 for 2 h, respectively. Comparison of ribosome-protected RNA (RF) and total mRNA abundance isolates the translational efficiency (TE) for each mRNA genome-wide. (B and C) Changes in TE following sotorasib treatment in MiaPaca-2 and MRTX1133 treatment in Panc10.05 cells. We identify mRNAs with decreased (TE down, red) and increased (TE up, blue) and unchanged translation (background, gray); three biological replicates; the most significantly affected genes are indicated on each side using a q value cutoff of 0.0001 and 0.1 for MiaPaca-2 and Panc10.05, respectively. (D and E) Metagene plot showing the reduction in ribosome coverage in TE down transcripts. KRAS G12C inhibition reduced overall ribosome coverage, while KRAS G12D inhibition significantly reduced the ribosome coverage in the 5′UTR region of the TE down transcripts. Paired two-sided Welch’s test across the coverage in 5′UTR, CDS, and 3′UTR showed a p value of = 7.50 × 10 −9 and 4.05 × 10 −4 for sotorasib and MRTX1133, respectively.

Article Snippet: The KRAS G12D specific inhibitor, MRTX1133, was purchased from MedChemExpress (HY-134813).

Techniques: Footprinting, Comparison, Genome Wide, Inhibition

Journal: Cell reports

Article Title: Mutant KRAS-driven selective mRNA translation reveals mechanisms and therapeutic vulnerabilities in cancer

doi: 10.1016/j.celrep.2026.117520

Figure Lengend Snippet: (A and B) Ribosome coverage on all ORFs showed increased ribosomes at the initiation site following sotorasib and MRTX1133 treatment in MiaPaca-2 and Panc10.05 cells, respectively ( p = 2.73 × 10 −2 ). No significant effect on the CDS in MRTX1133-treated Panc10.05 cells ( p = 0.414). (C) Ribosome coverage on TE down transcripts showed the accumulation of ribosomes upstream and downstream of the start site following sotorasib treatment in MiaPaca-2 ( p = 4.00 × 10 𢈒2 ), suggesting a slowdown in translation. (D) Ribosome coverage on TE down transcripts showed the accumulation of ribosomes upstream of the stop site following sotorasib treatment in MiaPaca-2 ( p = 1.66 × 10 −4 ), suggesting a block in translation elongation. (E) An increase of ribosome coverage between 70 and 90 nt region was observed in TE up transcripts following sotorasib (blue) treatment over control (black) in the 5′UTR and CDS around the start site ( p = 1.73 × 10 −2 ). (F) Fraction of pause-site codons (RxK, KKK, PP, PD, and PG) across the detected ORFs for the first 50 codons. (G, H, and I) Sucrose gradient fractionation of RNAse I digested polysome showing the accumulation of disome in MiaPaca-2 cells treated with sotorasib and quantification of the disome peak relative to DMSO ( p < 0.05). Immunoblot shows RPL5 and RPS10 in the indicated fractions collected from RNase I-digested polysome following DMSO vs. sotorasib treatment in MiaPaca-2. (J, K, and L) Immunoblot shows the induction of ZNF598, EDF1, p-ZAKα, ZAKα, RPS10-Ub following sotorasib treatment in MiaPaca-2. Anisomycin (ANS) treatment is included as a positive control for ribosome stalling and collision-induced stress signaling. β-actin is used as a loading control. (M) Mutant KRAS G12C inhibitor sotorasib affects translation initiation and elongation, resulting in ribosome stalling, while mutant KRAS G12D inhibitor MRTX1133 predominantly reduces translation initiation.

Article Snippet: The KRAS G12D specific inhibitor, MRTX1133, was purchased from MedChemExpress (HY-134813).

Techniques: Blocking Assay, Control, Fractionation, Western Blot, Positive Control, Mutagenesis

Journal: Cell reports

Article Title: Mutant KRAS-driven selective mRNA translation reveals mechanisms and therapeutic vulnerabilities in cancer

doi: 10.1016/j.celrep.2026.117520

Figure Lengend Snippet: (A and B) TE targets are downregulated in both sotorasib and MRTX1133 or only with sotorasib-treated MiaPaca-2 and Panc10.05 cells, respectively. (C) Translation efficiency of translation factors is affected by sotorasib, EEF1A1 being downregulated by the drug. (D–H) Immunoblot analyses show the downregulation of RPS6, EIF4E, EEF1A, and EEF2 following sotorasib treatment in MiaPaca-2 cells, SW837 cells, and RMC-7977 treatment in MiaPaca-2 cells and MRTX1133 treatment in Panc10.05 cells. β-actin is used as a loading control. (I) Intracellular immunostaining and FACS analysis show the downregulation of EEF1A in human primary PDAC-derived organoids treated with RMC-7977 (* p < 0.05, ** p < 0.01). (J–L) In vivo MiaPaca-2 xenograft studies show reduced tumor volume upon RMC-7977 treatment compared to vehicle, and immunoblots show the downregulation of RPS6, EIF4E, and EEF2 protein levels in xenograft tissues (* p < 0.05). (M and N) Western blot analysis and quantification of EEF1A1, EEF2, and RPS6 proteins show upregulation in KRAS G12D, or KRAS G12C compared to isogenic KRAS WT HEK293 cells (** p < 0.01 and *** p < 0.001). β-actin is used as a loading control. (O and P) Analysis of pancreatic, lung, and colorectal cancer cell lines with distinct KRAS genotypes [WT: H6C7], [G12D: Panc10.05, PANC-1, AsPC-1], [G12C: MiaPaca-2, H358, SW837] shows that KRAS G12D and KRAS G12C cells exhibit elevated protein expression of EEF1A1, EEF2, RPS6, and EIF4E compared to KRAS WT (** p < 0.01 and *** p < 0.001). β-actin is used as a loading control. (Q–S) Comparison of sotorasib TE targets with total proteomics data includes all eight trajectory clusters (C1-C8). Most of the TE down and TE up targets, which include cytoplasmic ribosomal proteins and translation factors, are downregulated at the protein level (clusters C1, C2, C5, C6, and C7). TE down mitochondrial ribosomal proteins are upregulated at the protein level (cluster C3, C4, C8).

Article Snippet: The KRAS G12D specific inhibitor, MRTX1133, was purchased from MedChemExpress (HY-134813).

Techniques: Western Blot, Control, Immunostaining, Derivative Assay, In Vivo, Expressing, Comparison

Journal: Cell reports

Article Title: Mutant KRAS-driven selective mRNA translation reveals mechanisms and therapeutic vulnerabilities in cancer

doi: 10.1016/j.celrep.2026.117520

Figure Lengend Snippet: (A and B) TE fold change analysis of common transcripts affected by sotorasib and CR-1-31B shows that mutant KRAS and EIF4A oppositely regulate the translation of these mRNAs. Most of the sotorasib TE down targets are TE upregulated following EIF4A inhibition with CR-1-31B. (C) TE fold change analysis of common translation factors between sotorasib and CR-1-31B reveals the upregulation of all the translation factors following CR-1-31B treatment, except for four proteins that are downregulated by CR-1-31B. (D and E) Relative luciferase activity driven by G-quadruplex (GQ) and GC-rich motifs in response to sotorasib, RMC-7977, or MRTX1133 treatment demonstrates that sotorasib induces GQ and GC-rich mRNA translation ( * p < 0.05 and *** p < 0.001). (F and G) Luciferase reporter assays using the full-length or mutated 5′UTR of EEF1A1 show altered luciferase activity upon CR-1-31B and Torin1 treatment in MiaPaca-2 cells (* p < 0.05 and *** p < 0.001). (H) Combination treatment of CR-1-31B and Torin1 with mutant KRAS inhibitors in a panel of cancer cell lines harboring either G12C or G12D KRAS mutations leads to an additive enhancement of cell death, based on the zero interaction potency (ZIP) model. (I) Summary of our findings shows that the mutant KRAS-dependent mechanism of translational control uncouples the regulation of translation machinery from the regulation of the rest of the mRNA translation. Mutant KRAS-dependent mechanism is distinct from the mTOR and EIF4A-dependent mechanism that depends on longer and structured 5′UTR features and controls the translation of a distinct subset of mRNAs.

Article Snippet: The KRAS G12D specific inhibitor, MRTX1133, was purchased from MedChemExpress (HY-134813).

Techniques: Mutagenesis, Inhibition, Luciferase, Activity Assay, Control