One of the most pressing challenges in oncology is the resistance that develops against therapies directed at mutated RAS proteins, which drive roughly one-third of human cancers. MSK scientists employed state-of-the-art X-ray crystallography alongside analyses of clinical specimens from patients treated with the tri-complex inhibitor daraxonrasib. This drug operates by forming a ternary complex among RAS, the molecular glue, and the effector protein cyclophilin A (CYPA), blocking oncogenic signaling. Their research uncovered three distinct resistance mechanisms: secondary mutations in RAS diminishing drug affinity; mutations in the BRAF gene promoting RAF protein dimerization that obstructs inhibitor binding; and CYPA mutations compromising complex formation, primarily observed in laboratory settings. Defining these mechanisms not only elucidates how tumors bypass therapy but also guides the design of combination treatments that could preempt or counteract resistance, thereby broadening the impact of tri-complex inhibitors far beyond daraxonrasib itself.

Another pivotal advance arises in tackling the heterogeneity within tumors, particularly diffuse midline glioma (DMG), a lethal pediatric brain cancer notorious for its cellular diversity and therapeutic refractoriness. A collaborative effort between MSK and Columbia University deployed a computational framework that integrates single-cell transcriptomics with protein regulatory network analyses. They identified seven conserved, coexisting tumor cell states, each governed by distinct master regulator proteins. By systematically evaluating 372 cancer drugs, the team predicted compounds capable of inactivating these regulators. Subsequent in vivo validation in murine models demonstrated that while single-agent therapies targeting minor cell populations had limited efficacy, rationally designed drug combinations effectively suppressed all malignant states. Notably, combinations such as avapritinib with ruxolitinib and avapritinib with larotrectinib led to significant survival benefits, underscoring the power of systems biology to translate tumor complexity into actionable therapeutic regimens.

The study of pancreatic cancer, a malignancy often detected too late for curative intervention, also benefited from MSK’s innovation in organoid technology. By differentiating human pluripotent stem cells into pancreatic progenitors and introducing oncogenic alterations—including KRAS activation alongside CDKN2A, TP53, and SMAD4 deletions—researchers successfully recreated early tumorigenic states in three-dimensional cultures. This human-derived model revealed critical differences from established murine models by demonstrating the necessity for multiple concurrent mutations to initiate tumorigenesis. Crucially, the researchers identified suppression of TET1, a DNA demethylase important for cellular homeostasis, as a key epigenetic alteration promoting cancer progression. Restoration of TET1 function emerges as a promising preventive strategy, offering insights into early molecular events preceding overt pancreatic cancer and highlighting the potential of epigenetic interventions.

Expanding into rare cancers, MSK scientists developed the first biobank of patient-derived organoids for appendiceal cancer, a disease marked by aggressive peritoneal dissemination and limited treatment options. The team isolated primary and metastatic tumor cells, growing them into 3D organoids that faithfully recapitulate tumor heterogeneity and progression. Comparative genomic analysis revealed mutations driving cancer-specific pathways and underscored increased chemoresistance in metastatic lesions. Importantly, pharmacological targeting of the RAS and WNT pathways yielded potent antitumor activity in lab models, presenting new therapeutic candidates for clinical translation. This resource represents a critical platform for the study of appendiceal cancer biology and tailored drug discovery in a malignancy that has historically lagged in research investment.

In the realm of cancer metabolism, MSK researchers tackled the challenge of developing selective covalent inhibitors that irreversibly bind target proteins without off-target toxicity. By pioneering a novel ‘scavenging proteomics’ approach that detects residual unbound proteins, the team achieved unprecedented accuracy in characterizing molecular interactions inside cells. Applying this methodology, they designed CNP7, a small molecule that covalently inhibits HMGCS1, the first committed enzyme in the mevalonate pathway essential for cholesterol synthesis and cell growth. Unlike statins, which reversibly inhibit downstream enzymes such as HMGCR and exhibit declining efficacy, CNP7 locks HMGCS1’s catalytic cysteine, producing durable pathway suppression. Cryo-electron microscopy crystallized the atomic details of this interaction, while diverse cancer cell lines demonstrated differential sensitivity, suggesting that direct HMGCS1 targeting could refine metabolic intervention strategies with enhanced efficacy and specificity.

Collectively, these studies underscore a multi-faceted assault on cancer by combining detailed mechanistic insight, computational prowess, and biological model innovation. From unraveling resistance to RAS inhibitors, decoding tumor heterogeneity in pediatric brain cancers, modeling early pancreatic tumorigenesis, to innovating organoid resources for rare appendiceal tumors, MSK researchers are catalyzing a new era in precision oncology. The molecular tool developed for metabolic inhibition not only advances therapeutic design but also sets new standards in verifying drug target engagement at the cellular level. These insights carve a promising path towards more durable and individualized treatments for cancers that have long posed formidable challenges.

By elucidating the complex interplay between genetic mutations, protein interactions, and metabolic dependencies across diverse tumor types, MSK’s integrated approach holds transformative potential for improving patient outcomes. These cutting-edge discoveries embody the power of convergence science, combining structural biology, computational analysis, and patient-derived models to dismantle cancer’s defense mechanisms. The emergence of such comprehensive strategies signifies a paradigm shift that may soon translate into clinical breakthroughs for some of the most intractable malignancies.

As researchers continue to expand upon these findings, the implications resonate universally within the cancer research community. The frameworks developed for overcoming resistance, co-targeting heterogeneous tumor cell populations, and dissecting metabolic vulnerabilities can be adapted broadly across cancer types. Through sustained interdisciplinary efforts, these advances herald a new chapter in designing smarter, more effective cancer therapies that anticipate and circumvent tumor adaptability, ultimately improving survival and quality of life for patients worldwide.

Subject of Research: Mechanisms of resistance to RAS-targeted therapies, tumor heterogeneity in pediatric brain tumors, pancreatic cancer development, appendiceal cancer models, and targeting cancer metabolism.

Article Title: Advanced Multidisciplinary Approaches Illuminate Cancer Resistance and Reveal Novel Therapeutic Targets at Memorial Sloan Kettering Cancer Center.

News Publication Date: Not specified.

Web References:

• Cell: https://www.cell.com/cell/fulltext/S0092-8674(26)00332-6
• Nature Genetics: https://www.nature.com/articles/s41588-026-02550-w
• Developmental Cell (Pancreatic cancer): https://www.sciencedirect.com/science/article/pii/S1534580726001590
• Developmental Cell (Appendiceal cancer): https://www.cell.com/developmental-cell/fulltext/S1534-5807(26)00161-9
• Journal of the American Chemical Society: https://pubs.acs.org/doi/10.1021/jacs.6c02556

References: See above web references.

Image Credits: Memorial Sloan Kettering Cancer Center.

Keywords

RAS mutations, cancer resistance, molecular glue drugs, tumor heterogeneity, pediatric brain tumors, diffuse midline glioma, organoids, pancreatic cancer, appendiceal cancer, cancer metabolism, covalent inhibitors, mevalonate pathway, precision oncology, structural biology, computational modeling

Cerebrospinal fluid continuously circulates throughout the brain and spinal cord, bathing the central nervous system in a dynamic environment of fluid motion. As this fluid flows, it imposes shear stress—frictional forces parallel to the surfaces of cells that line the CNS. The team at SickKids discovered that medulloblastoma cells sense these shear forces via specialized calcium-permeable ion channels present on their cell membranes. Activation of these channels triggers intracellular calcium influx, which subsequently initiates a signaling cascade, enhancing the tumor cells’ migratory capabilities. Such mechanosensitive signaling enables cancer cells to detach from the primary tumor, survive in the hostile environment of the CSF, and disseminate across the brain and spinal cord.

Crucially, the study identifies two distinct strategies to disrupt this mechano-metastatic signaling pathway. Through rigorous pre-clinical testing in sophisticated animal models, including zebrafish, the researchers demonstrated that pharmacological inhibition of the calcium channels or interference downstream in the associated molecular signaling significantly impedes the metastatic spread of medulloblastoma cells. These approaches mark a significant leap forward in designing targeted therapies that could effectively arrest tumor metastasis, a major cause of morbidity and mortality in pediatric brain cancer patients.

The investigation employed an innovative multi-model framework to unravel the complex interplay of mechanical forces and tumor biology. By integrating high-resolution imaging and genetic manipulation techniques in zebrafish with in vitro and murine models, the research team achieved an unprecedented level of insight into how fluid shear stress governs tumor cell behavior across species. This comparative approach not only validated the fundamental role of shear stress in metastasis but also highlighted conserved mechanotransduction pathways, enhancing the translational potential of their findings toward human therapy.

Fluid shear stress, often studied within the context of cardiovascular physiology and vascular endothelial cell function, is here firmly implicated as a key driver of cancer progression. The SickKids team uncovered how medulloblastoma cells co-opt these mechanical signals to facilitate their metastatic journey via unique ion channels, which act as mechano-sensors. These channels transduce external mechanical stimuli into biochemical signals that empower cells to survive detachment-induced apoptosis (anoikis) and navigate through the fluidic environment of the central nervous system.

This study sheds fresh light on the biophysical forces shaping tumor microenvironments, emphasizing that cancer progression is not solely governed by genetic and biochemical factors but also by physical cues from the tumor niche. Understanding the molecular underpinnings of fluid shear stress detection in medulloblastoma expands the horizon of mechanobiology in oncology, positioning mechanical forces as critical cancer modulators and actionable drug targets.

Dr. Xi Huang, senior scientist and principal investigator at SickKids, highlights the translational significance of these findings, noting that the identified small molecule inhibitors specifically block the fluid shear stress-dependent pathway with high therapeutic potency in preclinical models. This represents a promising step toward clinical application, potentially offering medulloblastoma patients a much-needed strategy to combat metastasis, which remains a daunting clinical challenge due to limited effective therapies.

Collaboration was central to this discovery, with contributions from experts in developmental biology and imaging, including Drs. Brian Ciruna and Madeline Hayes, who lent their zebrafish modeling expertise to visualize tumor cell dissemination in vivo under dynamic fluidic conditions. Their combined efforts enabled a detailed dissection of how mechanical forces influence tumor cell fate at cellular and tissue scales, enriching the mechanistic understanding necessary for precise therapeutic targeting.

The team’s findings also underscore the essential role of industry partnerships and commercialization initiatives at SickKids in propelling early-stage innovative research toward patient impact. Through support from SickKids Industry Partnerships & Commercialization (IP&C), the project is advancing the development pipeline for these promising inhibitors, aiming to navigate the critical translational steps from bench to bedside efficiently and safely.

Medulloblastoma metastasis currently limits survival rates, as disseminated tumor cells evade conventional therapies, making targeted interventions against the physical drivers of spread urgently needed. This research offers hope by unveiling a novel mechano-metastatic axis that can be pharmacologically targeted, paving the way for new precision medicine approaches in pediatric oncology.

The study was made possible through the support of multiple funding bodies, including the Arthur and Sonia Labatt Brain Tumour Research Centre, the Garron Family Cancer Centre, the Ontario Early Researcher Award, the Meagan Bebenek Foundation, the Brain Tumour Foundation of Canada, the Canadian Institutes of Health Research, and the SickKids Foundation. This collective investment underscores the importance of multidisciplinary and collaborative efforts in tackling some of the most formidable challenges in cancer biology and therapy.

By illuminating how natural fluid forces in the brain reshape tumor cell behavior and uncovering a druggable pathway, this research breaks new conceptual ground. It challenges traditional views of metastasis by placing biomechanical forces at center stage and highlights the promise of integrative, mechanobiology-informed strategies to improve outcomes for children afflicted with medulloblastoma.

Subject of Research: Mechanobiology of medulloblastoma metastasis and therapeutic targeting of fluid shear stress-induced signaling pathways.

Article Title: Fluid shear stress activates a targetable mechano-metastatic cascade to promote medulloblastoma metastasis

News Publication Date: 2-Sep-2025

Web References:

• https://www.nature.com/articles/s41551-025-01487-5
• https://www.sickkids.ca/
• https://ipc.sickkids.ca/
• http://dx.doi.org/10.1038/s41551-025-01487-5

Image Credits: The Hospital for Sick Children (SickKids)

Keywords

Cancer, Medulloblastoma, Fluid shear stress, Fluid dynamics, Mechanics, Brain tumor, Pediatric oncology, Metastasis, Mechanotransduction, Ion channels, Therapeutic targeting, Zebrafish modeling