Circular RNAs, distinct from linear RNA molecules, form covalently closed loop structures without 5’ to 3’ polarity, conferring them notable stability and unique biological functions. Their capacity to act as molecular sponges for microRNAs (miRNAs) positions them as critical regulators of gene expression, influencing a broad spectrum of cellular processes including proliferation, differentiation, and apoptosis. Researchers have increasingly recognized circRNAs as pivotal modulators of tumorigenesis across multiple cancer types; however, their precise roles in gastric cancer remain insufficiently characterized. This latest investigation offers the first comprehensive genome-wide insight into the alteration of circRNA landscapes within extracellular vesicles (EVs) circulating in patient plasma.

Utilizing state-of-the-art high-throughput RNA sequencing of plasma-derived extracellular vesicles from gastric cancer patients, the researchers identified a marked downregulation of circMORC1. Extracellular vesicles, nanoscale membranous structures secreted into the bloodstream, serve as intercellular messengers carrying nucleic acids and proteins, thereby influencing tumor microenvironment remodeling and systemic disease progression. The decreased abundance of circMORC1 in plasma EVs was paradoxical given its observed upregulation within malignant gastric epithelial cells, underscoring a complex compartmentalized expression pattern reflective of dynamic tumor-host interactions.

To resolve this apparent contradiction, functional characterization of circMORC1 was undertaken using cultured gastric cancer cell lines AGS and SGC-7901. Manipulation of circMORC1 levels revealed a robust promotion of tumorigenic phenotypes: increased cell proliferation, enhanced viability, accelerated migration, and significant inhibition of programmed cell death pathways. These phenotypic effects firmly establish circMORC1 as an oncogenic effector at the cellular level, suggesting its elevated intracellular presence actively drives malignancy progression.

Delving into the mechanistic basis of circMORC1’s oncogenic function, the study employed luciferase reporter and RNA pull-down assays to identify direct molecular interactions. A critical finding emerged demonstrating that circMORC1 binds and sequesters miR-103a-1-5p, a microRNA that ordinarily exerts tumor-suppressive effects by negatively regulating downstream signaling pathways. This interaction exemplifies the “sponge” model, where circRNAs attenuate miRNA availability, thereby modulating post-transcriptional gene silencing. Such a relationship corroborates the emerging paradigm where competing endogenous RNAs (ceRNAs) orchestrate complex gene expression networks in cancer.

Further transcriptomic profiling via RNA-sequencing and quantitative PCR assays implicated the Wnt signaling pathway as the principal downstream effector modulated by the circMORC1/miR-103a-1-5p axis. The Wnt pathway, a well-established driver of cellular proliferation, survival, and metastasis across multiple carcinomas, was found to be relieved from miRNA-mediated inhibition through circMORC1 sequestration of miR-103a-1-5p. This derepression catalyzes aberrant Wnt pathway activation, reinforcing oncogenic signaling cascades that facilitate gastric tumor growth and invasive potential.

Critically, this work delineates a novel regulatory feedback loop wherein circMORC1 acts as an oncogenic RNA sponge to counteract the suppressive effects of miR-103a-1-5p on the Wnt pathway, thereby stimulating tumorigenesis. This mechanistic insight not only enriches current models of gastric cancer molecular biology but also highlights circMORC1 as a compelling biomarker. Its differential abundance in circulatory EVs versus tumor cells offers a dual-faceted diagnostic angle—potentially improving early detection accuracy and monitoring disease progression or therapeutic response.

The clinical implications of these findings are profound. Given gastric cancer’s often late diagnosis and suboptimal prognoses, identifying stable, sensitive biomarkers in plasma EVs introduces a minimally invasive avenue for screening high-risk populations. Moreover, targeting the circMORC1/miR-103a-1-5p/Wnt signaling nexus opens new therapeutic strategies tailored to disrupt the oncogenic RNA interactome. Pharmacological approaches could involve diminishing circMORC1 expression or restoring miR-103a-1-5p functionality, thus reinstating tumor-suppressive pathways and curtailing malignant phenotypes.

This study is emblematic of a broader shift in cancer research emphasizing the non-coding genome’s regulatory capacity. While protein-coding genes have dominated therapeutic targeting historically, the emerging appreciation of circRNAs heralds a future where RNA-based diagnostics and interventions become integral to oncology practice. The stability of circRNAs in biofluids, coupled with their specificity and functional versatility, underscores their translational potential far beyond gastric cancer.

In addition, the compartmentalized expression pattern observed—circMORC1’s increase inside gastric cancer cells but decrease in circulating EVs—raises compelling biological questions regarding nucleic acid trafficking and intercellular communication. The selective packaging or clearance of circRNAs via EVs might constitute a tumor cell mechanism to modulate local versus systemic environments, possibly influencing immune evasion or metastatic niche conditioning. Further exploration of these dynamics may unravel novel facets of tumor biology and systemic regulation.

Furthermore, this research exemplifies the power of integrative multi-omics techniques combining RNA sequencing, biochemical assays, and functional cellular analyses to decode intricate molecular interplays. Such an approach not only strengthens the validity of discovered mechanisms but also accelerates the translation from molecular findings to clinical application, underscoring the vital role of interdisciplinary collaboration within biomedical sciences.

In conclusion, the revelation of circMORC1’s oncogenic role through miR-103a-1-5p sponging and subsequent Wnt pathway activation represents a significant leap forward in gastric cancer research. By defining a previously unappreciated RNA-based regulatory axis, this work opens novel avenues for biomarker development and targeted therapeutics. As research continues to unravel the expansive regulatory universe of circRNAs, their integration into precision oncology frameworks promises to transform gastric cancer management and improve patient outcomes worldwide.

Subject of Research: Regulation of gastric cancer progression by circMORC1 via miR-103a-1-5p sponging and Wnt signaling pathway modulation.

Article Title: CircMORC1 downregulated in plasma EVs promotes gastric cancer cell proliferation and invasion via miR-103a-1-5p sponging.

Article References:
Zhai, XM., Yang, YQ., Lin, L. et al. CircMORC1 downregulated in plasma EVs promotes gastric cancer cell proliferation and invasion via miR-103a-1-5p sponging. BMC Cancer 25, 1313 (2025). https://doi.org/10.1186/s12885-025-14688-7

Image Credits: Scienmag.com

DOI: https://doi.org/10.1186/s12885-025-14688-7

The study considered cancer data spanning from 2010 to 2019 for incidence and through 2022 for mortality, utilizing comprehensive datasets from the United States Cancer Statistics database and the National Center for Health Statistics, respectively. Early-onset cancer was rigorously defined as any malignancy diagnosed in patients aged 15 to 49 years, segmented into three subgroups: 15-29, 30-39, and 40-49 years. The researchers contrasted these findings against late-onset groups, defined as those aged 50-59, 60-69, and 70-79 years, to discern distinct or overlapping trends that could provide crucial etiological insights.

A total of over two million early-onset cancer cases were analyzed, revealing a striking predominance among females, who constituted 63.2% of the diagnoses in this younger cohort. Among women, breast cancer, thyroid cancer, and melanoma were the most frequently diagnosed malignancies, whereas for men, colorectal cancer, testicular cancer, and melanoma topped the list. This gender disparity in cancer types highlights the nuanced biological and possibly environmental factors that play differential roles by sex.

Further detailed analysis identified 14 cancer types exhibiting statistically significant increases in incidence within at least one early-onset age group. Notably, five cancers manifested rising trends exclusively in younger individuals without concomitant increases in older counterparts. These include melanoma, plasma cell neoplasms, cervical cancer, stomach cancer, and cancers affecting bones and joints. The fact that these particular cancers are rising solely among younger populations suggests unique risk factors or diagnostic trends possibly unrelated to those influencing older adults.

Conversely, nine cancer types showed heightened incidence both in early- and late-onset groups. Among these, female breast cancer, colorectal cancer, kidney cancer, testicular cancer, uterine cancer, pancreatic cancer, precursor B-cell non-Hodgkin lymphoma, diffuse large B-cell lymphoma, and mycosis fungoides/Sézary syndrome stand out. The presence of synchronous growth in both younger and older cohorts hints at either pervasive risk factors affecting broad age spans or improvements in detection technologies elevating case capture rates throughout the population.

Of particular concern is the substantial increase in early-onset diagnoses of female breast, colorectal, kidney, and uterine cancers, which together accounted for more than 80% of additional cancer cases seen in 2019 relative to 2010 expectations. This demonstrates a concentrated surge in malignancies known for significant morbidity and mortality, underscoring the urgent need for enhanced research into their etiologies and the refinement of screening guidelines to better capture cancers at earlier, more treatable stages in younger individuals.

Mortality trends, while initially seeming discordant with incidence, revealed that four cancers with increasing incidence—testicular cancer, uterine cancer, colorectal cancer, and cancers of the bones and joints—also experienced rising mortality rates in at least one age group. This troubling parallel increase suggests either more aggressive disease biology, delays in diagnosis, or inadequate treatment modalities impacting survival in these cancers among younger patients.

In contrast, ten of the cancers with rising incidence did not show corresponding mortality increases, a pattern that may indicate advancements in treatment outcomes, earlier detection, or overdiagnosis phenomena. These dynamics necessitate nuanced interpretation of incidence and mortality data, as rising cases do not uniformly translate to a heavier mortality burden.

The researchers emphasize the critical importance of comparing early-onset versus late-onset trends to glean potential clues regarding cancer drivers. The simultaneous increases observed across ages for many cancers may point to shared risk factors such as lifestyle changes, environmental exposures, or genetic predispositions that span generations. Alternatively, improved imaging and screening technologies could be responsible for heightened detection rates, especially in traditionally lower-risk younger populations.

Methodologically, the study’s strengths lie in its utilization of nationwide, population-level datasets, inclusion of mortality alongside incidence trends, and the innovative estimation of additional cases diagnosed relative to baseline years. These aspects provide robust context and a more comprehensive picture than previous analyses limited either in scope or temporal coverage.

However, the investigation is not without limitations. Perhaps most notably, it lacks granular patient-level data regarding individual risk factors, screening participation, or healthcare access disparities. Such information is crucial to unraveling causative elements that drive early-onset cancer increases and to formulating tailored preventive strategies. Without this, the study primarily serves as a vital epidemiologic overview rather than a direct mechanistic exploration.

This research carries significant translational implications, especially in the realm of cancer screening guidelines. Observations of rising early-onset breast and colorectal cancers have already contributed to recommendations lowering the age of routine screening initiation for these malignancies, signaling an evolving paradigm in personalized cancer prevention. Continued surveillance of incidence and mortality trends will be indispensable for guiding these efforts.

In sum, this comprehensive analysis reveals a complex and evolving cancer epidemiology characterized by rising early-onset malignancies, variable mortality trends, and differential patterns between young and older age groups. The findings challenge current understanding and highlight the urgent need for more in-depth studies assessing the multifactorial etiology of cancer in younger people. Ultimately, leveraging such epidemiological insights promises to shape more effective, age-adapted interventions that may alter the trajectory of cancer burden in the United States and beyond.

Subject of Research: Trends in incidence and mortality of early-onset and older-onset cancers in the United States.

Article Title: Trends in Cancer Incidence and Mortality Rates in Early-Onset and Older-Onset Age Groups in the United States, 2010–2019

News Publication Date: 8-May-2025

Web References:

• Cancer Discovery Journal
• DOI link

Keywords: Cancer, Early-onset cancer, Breast cancer, Colorectal cancer, Pancreatic cancer, Incidence trends, Mortality trends, Cancer screening, Age-related cancer epidemiology

In a groundbreaking study that has the potential to revolutionize cancer treatment, researchers from Tel Aviv University have successfully utilized CRISPR technology to eliminate a significant portion of head and neck tumors in model animals. The research was spearheaded by Dr. Razan Masarwy from the laboratory of Professor Dan Peer, who is regarded as a prominent figure in the development of mRNA-based therapies. This innovative application of CRISPR not only challenges previous assumptions about gene targeting in cancer but also offers new avenues for advanced cancer therapies.

Head and neck cancers represent a critical health concern, ranking fifth in cancer mortality worldwide. These tumors primarily originate from the oral cavity and can metastasize to other regions if not detected early. The advantage of targeting localized tumors lies in the potential for effective intervention before the cancer spreads. Professor Peer emphasizes that the focus of their research was to explore the genetic editing of a specific gene—SOX2—that plays a crucial role in cancer cell survival. By demonstrating that certain genes are indispensable for the sustenance of cancer cells, the study identifies them as prime targets for CRISPR intervention.

Within the context of this study, researchers employed a state-of-the-art nano-lipid delivery system to encapsulate the CRISPR components and specifically target the EGF receptor on the surface of cancer cells. These synthetic lipid particles were engineered to mimic biological membranes, providing a safe and efficient means for delivering genetic editing tools directly into the tumor. This approach enables the direct and precise excision of the cancer-specific SOX2 gene from the DNA of malignant cells using CRISPR’s molecular "scissors."

The efficacy of this CRISPR application was noteworthy, with results showing up to 50% tumor eradication following a regimen of three injections over an 84-day period. What is particularly striking is that this remarkable reduction in tumor size was absent in control groups. This outcome not only substantiates the anticipated impact of targeting SOX2 through CRISPR but also marks a significant leap in cancer research and treatment methodologies.

The study builds on previous work in which Professor Peer and his team applied CRISPR for gene disruption in cancer cells within specific cell types. Their current findings extend this pioneering approach to head and neck cancers for the first time, demonstrating the broader applicability of CRISPR technology in oncology. Professor Peer notes the essential nature of understanding cancer cell biology: certain genes, like SOX2, differ in their roles across various cancers, presenting unique opportunities for targeted therapies.

While the application of CRISPR in cancer therapy has generally been met with skepticism—largely due to the belief that targeting a single gene would not be adequate to dismantle the complexity of cancer—this study challenges that notion. It paves the way for future research aimed at exploring other genes that may be equally pivotal in cancer cell survival and expansion. Consequently, ongoing work seeks to investigate these aspects further in diverse cancer types such as myeloma, lymphoma, and liver cancer.

As the researchers highlight, the implications of this study go beyond immediate tumor removal. The potential activation of additional genetic pathways in cancer cells may necessitate further gene targeting, but the foundational principle remains that some genes act as lynchpins in cancerous survival. By understanding these relationships, researchers aim to refine and enhance CRISPR-driven therapies for broader cancer applications.

The study was bolstered by support from the European Union’s Horizon 2020 research and innovation program and the Shmunis Fund for gene editing, emphasizing the importance of collaborative efforts in advancing scientific frontiers. These partnerships not only provide necessary funding but also encourage innovative approaches to tackle unmet clinical needs in oncology.

In conclusion, this recent research encapsulates the promise of genetic editing technologies like CRISPR in transforming cancer treatment landscapes. It represents both a critical step in understanding cancer resistance mechanisms and a hopeful direction toward more effective and personalized therapies. As scientists continue to unravel the complexities of cancer biology, the future of CRISPR in oncology appears increasingly bright.

The link to the published findings in the journal Advanced Science is a crucial resource for those wishing to delve deeper into the methodologies and implications of this research.

Subject of Research: CRISPR Gene Editing in Cancer Cells
Article Title: Targeted CRISPR Therapy Brings New Hope for Head and Neck Cancer
News Publication Date: 2023
Web References: N/A
References: N/A
Image Credits: Tel Aviv University

Keywords: CRISPR, Gene Editing, Head and Neck Cancer, Cancer Research, mRNA-Based Therapies, Tumor Genetics, Precision Medicine, Tel Aviv University.