Extensive preclinical validation of combined RMC-4550 and LY3214996 supports clinical investigation for KRAS mutant pancreatic cancer

Over 90% of pancreatic cancers present mutations in KRAS, one of the most common oncogenic drivers overall. Currently, most KRAS mutant isoforms cannot be targeted directly. Moreover, targeting single RAS downstream effectors induces adaptive resistance mechanisms. We report here on the combined inhibition of SHP2, upstream of KRAS, using the allosteric inhibitor RMC-4550 and of ERK, downstream of KRAS, using LY3214996. This combination shows synergistic anti-cancer activity in vitro, superior disruption of the MAPK pathway, and increased apoptosis induction compared with single-agent treatments. In vivo, we demonstrate good tolerability and efficacy of the combination, with significant tumor regression in multiple pancreatic ductal adenocarcinoma (PDAC) mouse models. Finally, we show evidence that 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) can be used to assess early drug responses in animal models. Based on these results, we will investigate this drug combination in the SHP2 and ERK inhibition in pancreatic cancer (SHERPA; ClinicalTrials.gov: NCT04916236) clinical trial, enrolling patients with KRAS-mutant PDAC.This work was funded by the American Association for Cancer Research, Lustgarten Foundation, and Stand Up to Cancer as a Pancreatic Cancer Collective New Therapies Challenge grant (grant no. SU2C-AACR-PCC-01-18)

Bcl3 Couples Cancer Stem Cell Enrichment With Pancreatic Cancer Molecular Subtypes

[Background & Aims]: The existence of different subtypes of pancreatic ductal adenocarcinoma (PDAC) and their correlation with patient outcome have shifted the emphasis on patient classification for better decision-making algorithms and personalized therapy. The contribution of mechanisms regulating the cancer stem cell (CSC) population in different subtypes remains unknown. [Methods]: Using RNA-seq, we identified B-cell CLL/lymphoma 3 (BCL3), an atypical nf-κb signaling member, as differing in pancreatic CSCs. To determine the biological consequences of BCL3 silencing in vivo and in vitro, we generated bcl3-deficient preclinical mouse models as well as murine cell lines and correlated our findings with human cell lines, PDX models, and 2 independent patient cohorts. We assessed the correlation of bcl3 expression pattern with clinical parameters and subtypes. [Results]: Bcl3 was significantly down-regulated in human CSCs. Recapitulating this phenotype in preclinical mouse models of PDAC via BCL3 genetic knockout enhanced tumor burden, metastasis, epithelial to mesenchymal transition, and reduced overall survival. Fluorescence-activated cell sorting analyses, together with oxygen consumption, sphere formation, and tumorigenicity assays, all indicated that BCL3 loss resulted in CSC compartment expansion promoting cellular dedifferentiation. Overexpression of BCL3 in human PDXs diminished tumor growth by significantly reducing the CSC population and promoting differentiation. Human PDACs with low BCL3 expression correlated with increased metastasis, and BCL3-negative tumors correlated with lower survival and nonclassical subtypes. [Conclusions]: We demonstrate that bcl3 impacts pancreatic carcinogenesis by restraining CSC expansion and by curtailing an aggressive and metastatic tumor burden in PDAC across species. Levels of BCL3 expression are a useful stratification marker for predicting subtype characterization in PDAC, thereby allowing for personalized therapeutic approaches.This work was supported by the Deutsche Forschungsgemeinschaft (grants AL 1174/4-1, AL1174/4-2, and Collaborative Research Center 1321 “Modeling and Targeting Pancreatic Cancer” to Hana Algül; SFB824 Z2 to Katja Steiger), the Deutsche Krebshilfe (grant 111646 to Hana Algül), a Ramon y Cajal Merit Award from the Ministerio de Economía y Competitividad, Spain (to Bruno Sainz Jr), a Coordinated Grant from Fundación Asociación Española Contra el Cáncer (GC16173694BARB to Bruno Sainz Jr), funding from The Fero Foundation (to Bruno Sainz Jr), and a Proyecto de Investigacion de Salud, ISCIII, Spain (no. PI18/00757 to Bruno Sainz Jr). Jiaoyu Ai is supported by the “China Scholarship Council” grant program

Levels of the Autophagy-Related 5 Protein Affect Progression and Metastasis of Pancreatic Tumors in Mice

[Background and Aims]: Cells in pancreatic ductal adenocarcinoma (PDAC) undergo autophagy, but its effects vary with tumor stage and genetic factors. We investigated the consequences of varying levels of the autophagy related 5 (Atg5) protein on pancreatic tumor formation and progression. [Methods]: We generated mice that express oncogenic Kras in primary pancreatic cancer cells and have homozygous disruption of Atg5 (A5;Kras) or heterozygous disruption of Atg5 (A5+/–;Kras), and compared them with mice with only oncogenic Kras (controls). Pancreata were analyzed by histology and immunohistochemistry. Primary tumor cells were isolated and used to perform transcriptome, metabolome, intracellular calcium, extracellular cathepsin activity, and cell migration and invasion analyses. The cells were injected into wild-type littermates, and orthotopic tumor growth and metastasis were monitored. Atg5 was knocked down in pancreatic cancer cell lines using small hairpin RNAs; cell migration and invasion were measured, and cells were injected into wild-type littermates. PDAC samples were obtained from independent cohorts of patients and protein levels were measured on immunoblot and immunohistochemistry; we tested the correlation of protein levels with metastasis and patient survival times. [Results]: A5+/–;Kras mice, with reduced Atg5 levels, developed more tumors and metastases, than control mice, whereas A5;Kras mice did not develop any tumors. Cultured A5+/–;Kras primary tumor cells were resistant to induction and inhibition of autophagy, had altered mitochondrial morphology, compromised mitochondrial function, changes in intracellular Ca2+ oscillations, and increased activity of extracellular cathepsin L and D. The tumors that formed in A5+/–;Kras mice contained greater numbers of type 2 macrophages than control mice, and primary A5+/–;Kras tumor cells had up-regulated expression of cytokines that regulate macrophage chemoattraction and differentiation into M2 macrophage. Knockdown of Atg5 in pancreatic cancer cell lines increased their migratory and invasive capabilities, and formation of metastases following injection into mice. In human PDAC samples, lower levels of ATG5 associated with tumor metastasis and shorter survival time. [Conclusions]: In mice that express oncogenic Kras in pancreatic cells, heterozygous disruption of Atg5 and reduced protein levels promotes tumor development, whereas homozygous disruption of Atg5 blocks tumorigenesis. Therapeutic strategies to alter autophagy in PDAC should consider the effects of ATG5 levels to avoid the expansion of resistant and highly aggressive cells.This study was supported in part by the Mildred-Scheel-Professur der Deutschen Krebshilfe 111464, DFG AL 1174/6-1 to H.A., DFG DI 2299/1-1 to K.N.D., DFG SFB1321 (S01) to K.S. and W.W., and the German Federal Ministry of Education and Research to the German Center for Diabetes Research (DZD e.V.) to J.A

A Guide to Preprinting for Early Career Researchers

The use of preprints, research manuscripts shared publicly before the traditional peer-review process, is becoming more common in the life sciences. Early career researchers (ECRs) benefit from posting preprints as they are shareable, citable, and prove productivity. However, the decision to preprint a manuscript involves a discussion among all co-authors, and ECRs are often not the decision-makers. Therefore, ECRs may find themselves in situations where they are interested in posting a preprint but are unsure how to approach their co-authors or advisor about preprinting. Leveraging our own experiences as ECRs, and feedback from the research community, we have constructed a guide for ECRs who are considering preprinting - to enable them to take ownership over the process, and to raise awareness about preprinting options. We hope that this guide helps ECRs to initiate conversations about preprinting with co-authors and encourage them to preprint their future research

Supplemental materials for preprint: A Guide to Preprinting for Early Career Researchers

Supplemental materials for: A Guide to Preprinting for Early Career Researcher

Anwendungen der Fourier-Transformation auf Bilddaten aus der zerstoerungsfreien Pruefung

TIB: RA 3123 (122),2 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLE2. ed.DEGerman