The molecular mechanisms of CRISPR-guided knockout, the genetic vulnerabilities it has uncovered in PDAC, the therapeutic strategies emerging from this work, and the delivery systems supporting clinical translation are examined.
Abstract
Pancreatic ductal adenocarcinoma (PDAC) remains one of the most lethal malignancies worldwide, characterized by late-stage diagnosis, profound chemoresistance, and a five-year survival rate that barely exceeds 12%. The fibrotic stromal barrier surrounding the tumor actively suppresses immune infiltration and blocks drug delivery, rendering conventional treatment options largely ineffective. CRISPR-Cas9-mediated gene knockout represents a promising strategy to overcome this stromal barrier-associated therapeutic resistance by enabling precise disruption of genes that sustain desmoplastic signaling, stromal-immune crosstalk, and drug efflux pathways within the tumor microenvironment. In this context, CRISPR-Cas9-guided gene knockout has opened a new chapter in PDAC research by enabling precise, scalable analysis of the cancer genome. Functional screens using this technology have mapped critical oncogenic dependencies, identifying mutant KRAS, TP53, SMAD4, and CDKN2A as high-value targets, while simultaneously revealing synthetic lethal interactions that were previously inaccessible through pharmacological approaches. These discoveries are now being translated into therapeutic strategies aimed at silencing driver mutations, restoring chemosensitivity, and reprogramming the immunosuppressive tumor microenvironment. Delivery platforms, including lipid nanoparticles, viral vectors, and extracellular vesicles, are being refined to navigate the physical barriers unique to PDAC. Patient-derived organoids and xenograft models are providing the translational framework needed to evaluate these interventions under clinically relevant conditions. This review examines the molecular mechanisms of CRISPR-guided knockout, the genetic vulnerabilities it has uncovered in PDAC, the therapeutic strategies emerging from this work, and the delivery systems supporting clinical translation. The remaining barriers and the steps needed to bring this technology to patients are also discussed.
Background/Objectives: Pancreatic ductal adenocarcinoma (PDAC) remains one of the most lethal malignancies because of aggressive tumor biology, pervasive therapeutic resistance, rapid adaptive reprogramming, and a profoundly immunosuppressive tumor microenvironment. This review summarizes recent advances in KRAS-targeted therapies, DNA damage response (DDR)-directed strategies, immune-redirection platforms, and tumor microenvironment modulation. Methods: We conducted a narrative review of peer-reviewed publications, clinical trial reports, trial registries, and selected conference data addressing emerging therapeutic strategies for PDAC. Results: KRAS-targeted therapies, including KRAS G12D-selective and multi-selective RAS(ON) inhibitors, have demonstrated substantial preclinical and emerging clinical activity while revealing diverse mechanisms of adaptive resistance. DDR-directed approaches are expanding beyond BRCA-mutated disease toward functional homologous recombination deficiency, replication stress, and synthetic lethality. In parallel, bispecific antibodies, T-cell engagers, and CAR-T-cell therapies have generated preliminary evidence of antitumor activity, although stromal exclusion, antigen heterogeneity, and immune suppression remain major barriers. These advances indicate that therapeutic resistance in PDAC is a dynamic process involving interconnected oncogenic, genomic, stromal, metabolic, and immune mechanisms. Conclusions: Future progress will require biologically informed treatment frameworks integrating complementary therapeutic modalities according to baseline tumor biology and treatment-induced adaptive states, supported by longitudinal biomarkers and rational clinical trial design.
Jun Kim, Seounghun Kang· Pharmaceutics· 0 citations
The strategies detailed here define a next-generation precision-oncology paradigm capable of anticipating tumor evolution, overcoming resistance, and preventing metastatic relapse, by uniting AI-guided design, circadian reprogramming, dormancy eradication, and logic-gated delivery.
Anmar Ghanim Taki, Abdulkareem Shareef, Vimal Arora et al.· Iranian Journal of Basic Med...· 0 citations
Metastatic cancer remains the leading cause of cancer-related mortality, yet tumor cell–intrinsic mechanisms restraining metastatic dissemination remain incompletely defined. Here, we perform an unbiased in vivo genome-wide CRISPR/Cas9 loss-of-function screen in a breast cancer xenograft model to identify regulators of metastatic progression. This approach uncovers clinically relevant metastasis suppressor genes (MSGs), including VPS45, CMTR2, RBSN, and NF2, whose loss enhances lung colonization. Functional validation demonstrates that depletion of these genes promotes epithelial-to-mesenchymal transition, migration, invasion, intravasation, and angiogenesis, whereas CRISPR-mediated activation suppresses metastatic spread. Integration with patient datasets reveals reduced expression in tumors and associations with advanced disease, with higher expression trending toward improved outcomes. Notably, CMTR2 loss induces vascular remodeling and intratumoral heterogeneity, supporting a role in tumor–vascular interactions. Collectively, this study identifies a network of MSGs that constrain tumor dissemination and highlights the power of in vivo CRISPR functional genomics to uncover regulators of metastatic disease. Triple-negative breast cancer (TNBC) is a highly metastatic disease with poor patient outcomes. Here, the authors discover through in vivo CRISPR screening VPS45, RBSN, CMTR2, and NF2 as metastasis suppressor genes in TNBC, restraining epithelial-mesenchymal transition, intravasation, and metastatic dissemination.
Soaad Galal, Leslie Chaltel Lima, Ni Wang et al.· Nature Communications· 0 citations
It is hypothesized that genome-wide CRISPRa screening will uncover subtype-specific genetic dependencies and drug resistance mechanisms, offering novel therapeutic insights in leukemia subtype biology, guiding future personalized treatment strategies.
Jeffrey Sullivan, Xiaozen Wen, Gabriela Flores-Vargas et al.· Journal of Immunology· 0 citations
Key methodological steps for achieving high-efficiency lentiviral transduction and selection are described, enabling the successful application of EPIKOL CRISPR screens in chemoresistant TNBC models.
O. Yedier-Bayram, Elif Ayca Guvener, T. Bagci-Onder· Journal of Visualized Experi...· 0 citations
Esophageal adenocarcinoma (EAC) is a genetically heterogeneous malignancy with few recurrent drivers, limiting effective targeted therapies. Although EAC arises from Barrett’s esophagus (BE), mechanisms driving progression from this premalignant state to invasive cancer remain unclear. We combined pooled CRISPR-Cas9 loss-of-function screening, in vivo tumorigenicity assays, and Perturb-seq profiling to define functional drivers of BE transformation. We identified 37 tumor suppressors whose loss promotes progression to EAC, defining a functional landscape of tumor initiation. Despite genetic diversity, these losses converged on four transcriptional programs involving metabolic reprogramming, cell cycle progression, RNA processing, and cellular motility. Furthermore, we identify loss of NIPBL, TGFBR2, and RPL22 as key mediators of resistance to platinum- and taxane-based chemotherapy. Collectively, these findings provide a unifying framework for genomic heterogeneity in EAC, uncover underappreciated tumor suppressor pathways, and establish a resource to guide mechanistic and translational studies aimed at improving treatment strategies in this aggressive cancer.
