The study team, led by researchers at Zhejiang University and The Third Affiliated Hospital of Guangzhou Medical University, analyzed ten human cervical tissue samples spanning the full pathological continuum. Single-cell RNA sequencing allowed them to profile thousands of individual cells, resolving not only which cell types were present at each disease stage but also how their gene-expression programs shifted as lesions progressed. Whole-genome bisulfite sequencing added a crucial layer of epigenetic information, revealing how DNA methylation patterns change across cell types during carcinogenesis, while spatial transcriptomic data from a public cohort confirmed that the cellular relationships observed in dissociated single-cell data hold true within intact tissue architecture.

One of the most striking findings is that disease progression is accompanied by a marked increase in NK/T cell infiltration. As normal tissue advances through LSIL and HSIL toward invasive carcinoma, immune cells of the NK and T lineages crowd increasingly into the lesion environment. This might, at first glance, seem encouraging, since cytotoxic lymphocytes are the very cells capable of destroying tumor cells. Yet the infiltration coincides with upregulation of galectin-9, an immune checkpoint ligand encoded by the LGALS9 gene. Galectin-9 is known to bind Tim-3 on T cells, a interaction that dampens antitumor immunity and drives T-cell exhaustion. In other words, the tumor microenvironment appears to respond to escalating immune pressure by deploying an immunosuppressive ligand, a classic example of adaptive immune resistance.

The epigenetic data revealed something particularly interesting about how this deployment unfolds over time. The LGALS9 promoter underwent progressive demethylation beginning at the low-grade squamous intraepithelial lesion stage, indicating that the gene was being epigenetically primed for expression long before invasive cancer appeared. However, robust transcriptional induction of LGALS9 only became prominent at the high-grade lesion stage, coinciding with activation of interferon-gamma response programs. This temporal separation between demethylation and transcriptional activation suggests a two-step mechanism: early epigenetic poising followed by inflammatory triggering. The researchers found a remarkably tight correlation between interferon-gamma activity and LGALS9 expression at the sample level, with a Pearson correlation coefficient of 0.95, indicating that the very immune cells infiltrating the lesion may be inducing the ligand that ultimately silences them.

Beyond galectin-9, trajectory analysis of the single-cell data delineated the evolution of CD8-positive T cells across disease stages and identified TFCP2 as a transcriptional regulator whose activity is associated with patient prognosis. The study also documented enrichment of LAMP3-positive mature dendritic cells in tumor tissues compared with normal controls. These dendritic cells, which emerge along a maturation trajectory from conventional cDC1 and cDC2 subsets, carried a mixture of costimulatory molecules such as CD40 and CD80 and inhibitory checkpoint molecules including CD274, IDO1, and LGALS9 itself, suggesting that even the antigen-presenting arm of the immune response becomes entangled in the checkpoint machinery as cancer develops.

Multiplex immunohistochemistry provided protein-level confirmation of the story told by the sequencing data. Staining for exhausted CD8-positive T cells, marked by the co-expression of CD3, CD8, and Tim-3, alongside staining for the epithelial marker pan-cytokeratin and galectin-9, showed that galectin-9-positive epithelial cells increase in abundance as tissue progresses from normal cervix through LSIL and HSIL to cancer. The physical co-localization of Tim-3-expressing exhausted T cells with galectin-9-expressing epithelium within the same tissue sections strengthens the argument that this ligand-receptor pair represents a functional axis of immune evasion operating during precancerous progression, not merely a correlate of advanced disease.

Perhaps the most translational portion of the work came from animal experiments. The researchers established an ectopic subcutaneous syngeneic cervical cancer model in immunocompetent mice, an experimental system in which the immune system is fully intact and therefore capable of mounting genuine antitumor responses. Blocking galectin-9 in this model reduced tumor burden, demonstrating that the protein is not simply a passive biomarker but an active contributor to tumor growth. More strikingly, combining galectin-9 blockade with an agonist antibody against GITR, a costimulatory receptor on T cells, significantly enhanced the clonal expansion and cytotoxic activity of CD8-positive T cells. This combination strategy suggests that releasing one brake on the immune system while simultaneously pressing the accelerator may produce therapeutic effects greater than either intervention alone.

The findings arrive at a moment when immune checkpoint blockade has transformed the treatment of many cancers but has delivered comparatively modest results in cervical cancer. Understanding which checkpoint pathways are active at which stages of disease could allow clinicians to intervene earlier and more precisely. The observation that LGALS9 epigenetic poising begins at the LSIL stage is particularly provocative, since low-grade lesions are common, usually regress spontaneously, and are typically managed conservatively. If reliable markers of galectin-9 activation could be incorporated into screening algorithms, they might help distinguish the minority of low-grade lesions destined for progression from those that will resolve, sparing unnecessary procedures while directing attention to lesions that truly warrant close surveillance.

The study also illustrates the growing power of integrated multi-omics approaches in cancer biology. No single technology used here could have revealed the full sequence of events. Single-cell transcriptomics exposed the cellular composition and signaling programs of each lesion stage, but only DNA methylation profiling revealed that LGALS9 had been epigenetically prepared in advance of its expression, and only spatial transcriptomics could verify that the relevant cell populations occupy adjacent territories within intact tissue. Copy number variation inference, pseudotime trajectory modeling, and regulon analysis with tools such as pySCENIC and Monocle2 added further resolution, while methylation-based deconvolution using EpiSCORE extended the key NK/T cell infiltration trend across a larger cohort of twenty-one bulk tissue samples.

Caveats remain, as they do in any early-stage translational study. The human cohort comprised ten deeply profiled samples, and the syngeneic mouse model, while immunocompetent, does not fully recapitulate HPV-driven human cervical carcinogenesis. Clinical testing of galectin-9 blockade in cervical cancer patients would need to demonstrate safety and efficacy in the neoadjuvant, recurrent, or metastatic settings where immunotherapy is currently deployed. Nevertheless, by pinpointing a checkpoint ligand whose activation is detectable during precancerous progression and whose blockade shows antitumor efficacy in vivo, the study provides both a mechanistic framework for understanding immune evasion in cervical carcinogenesis and a concrete, testable therapeutic hypothesis. For a disease that remains a leading cause of cancer death among women globally, that combination of mechanistic insight and actionable target represents a meaningful step forward.

Subject of Research: Multi-omics analysis of immune evasion during cervical carcinogenesis and galectin-9 as a candidate immunotherapeutic target

Article Title: Multi-omics analysis of cervical carcinogenesis reveals galectin-9 driven immune evasion as a candidate immunotherapeutic target

Article References: Multi-omics analysis of cervical carcinogenesis reveals galectin-9 driven immune evasion as a candidate immunotherapeutic target. (n.d.). https://doi.org/10.1186/s12935-026-04458-1

Image Credits: AI Generated

DOI: 10.1186/s12935-026-04458-1

Keywords: cervical cancer, galectin-9, LGALS9, single-cell RNA sequencing, spatial transcriptomics, DNA methylation, CD8-positive T cells, immune evasion, immunotherapy, tumor microenvironment, interferon-gamma, cervical carcinogenesis

The research team, led by Di Liu and Guo Deng of The People’s Hospital of the Qiandongnan Miao and Dong Autonomous Prefecture, together with Hanluo Yang and Qingyu Zhang of Jinping County People’s Hospital, began by asking a basic pharmacological question: how sensitive are bladder cancer cells to trifolirhizin? Using cell counting kit-8 assays on two widely studied human bladder carcinoma cell lines, T24 and UMUC3, they measured the concentration required to kill half of the cells. The answer was strikingly consistent across both lines, with IC50 values of 67.41 micromolar for T24 cells and 72.58 micromolar for UMUC3 cells. Those figures establish trifolirhizin as a genuine cytotoxic agent against these aggressive tumor cells rather than a marginal one, and they provided the dosing foundation for every experiment that followed.

Viability alone, however, tells only part of the story in oncology research. A compound can poison cells without touching the behaviors that actually make cancer dangerous: uncontrolled replication and tissue invasion. To probe these hallmarks, the researchers turned to colony formation assays, which measure the capacity of individual tumor cells to multiply into visible colonies over days and weeks. Trifolirhizin treatment markedly reduced the number of colonies the bladder cancer cells could establish, signaling a direct suppression of long-term proliferative potential. This kind of assay is widely regarded as a stringent test of a drug’s anti-tumor character, because surviving even a brief exposure is not enough; the cells must retain the full machinery for sustained growth, and trifolirhizin appears to compromise exactly that machinery.

Invasion was the next target on the team’s list. Malignant tumors earn their lethal reputation not from where they start but from where they spread, and bladder cancer is no exception. The investigators used transwell migration assays to quantify how many cells could push through a membrane barrier, a standard laboratory proxy for invasive behavior. Trifolirhizin treatment significantly decreased the number of invading cells. Crucially, the molecular correlates of that behavioral shift told a coherent story: levels of vimentin, an intermediate filament protein that supports cellular motility and is a classic marker of epithelial-mesenchymal transition, dropped after treatment, while E-cadherin, an adhesion molecule that helps hold epithelial cells together and restrains migration, increased. In other words, the compound appeared to pull the cells back from a mobile, invasive state toward a more settled, epithelial identity.

Perhaps the most forward-looking dimension of the study concerns immune evasion, the process by which tumors render themselves invisible or hostile to the body’s defensive cells. The researchers found that trifolirhizin-treated bladder cancer cells became more vulnerable to CD8-positive T cell-mediated cytotoxicity, the principal killing mechanism of cellular antitumor immunity. Alongside this, they measured elevated levels of interferon-gamma, a cytokine that serves as both a marker and a driver of an activated antitumor immune response. By quantifying cytokines in the culture environment, the team showed that the compound did not merely make tumor cells more fragile; it also shifted the signaling landscape in ways that favor immune recognition and attack. That dual action, direct toxicity plus immune reactivation, is precisely the profile that modern immunotherapy research seeks to amplify.

With the phenotypic effects established, the study moved to its mechanistic core: the AKT/NF-κB pathway. Protein kinase B, universally abbreviated as AKT, is a kinase that promotes survival and growth in countless cancers, while nuclear factor kappa-B is a transcription factor that switches on genes supporting inflammation, survival, invasion, and immune escape. The two are functionally intertwined, with AKT activity frequently reinforcing NF-κB signaling. Using immunoblotting, the researchers showed that trifolirhizin treatment attenuated the phosphorylation of both proteins, effectively dialing down the pathway’s activity. Because phosphorylation is the molecular switch that activates these signaling proteins, its reduction means the pathway was genuinely silenced, not merely perturbed.

Correlation is not causation, however, and the team designed an elegant validation experiment to close that gap. They co-treated the cells with SC79, a pharmacological activator of AKT that forces the pathway back into gear even in the presence of an upstream inhibitor. The result was decisive. When SC79 was added alongside trifolirhizin, the compound’s effects on proliferation, apoptosis, invasion, and immune escape indicators in T24 cells were substantially reversed. Markers that trifolirhizin had pushed in an antitumor direction drifted back toward their malignant baseline. This rescue experiment provides the strongest form of evidence short of genetic knockout that the AKT/NF-κB axis is not merely one of many targets but the central conduit through which trifolirhizin exerts its anticancer activity in bladder carcinoma cells.

Laboratory dishes are one thing; living tumors are another. To test whether the findings would survive the far more complex environment of an organism, the researchers turned to xenograft models, in which human bladder cancer cells are implanted into mice and allowed to form tumors. Animals treated with trifolirhizin carried a visibly reduced tumor burden compared with untreated controls, confirming that the compound’s cytotoxic and antiproliferative effects translate into slower tumor growth in vivo. Tissue analysis reinforced the cellular findings: hematoxylin and eosin staining, immunohistochemistry, and immunoblotting revealed reduced vimentin expression within the tumors, increased markers of apoptosis, and elevated interferon-gamma levels. Once again, the AKT/NF-κB pathway showed consistently inhibited expression in tumors harvested from trifolirhizin-treated mice, mirroring the in vitro mechanism at the level of intact tissue.

The convergence of these results paints trifolirhizin as a multimodal therapeutic candidate, a phrase the authors themselves use in their conclusion. By suppressing proliferation, blunting invasion, promoting apoptosis, and enhancing immune-mediated killing, all through downregulation of a single druggable signaling pathway, the compound occupies an unusually versatile position for a natural product. Pterocarpan flavonoids of this class have long attracted attention in chemoprevention and anticancer research, but their efficacy and molecular mechanisms in bladder carcinoma had remained unexplored until this study. The work was approved by the ethics committee of The People’s Hospital of the Qiandongnan Miao and Dong Autonomous Prefecture, and the authors declare no competing interests.

Cautious optimism is the appropriate stance. The IC50 values lie in the high micromolar range, and the journey from xenograft mice to human patients involves hurdles of pharmacokinetics, safety, and formulation that no cell culture or animal model can predict. Still, the study’s design, combining functional assays, cytokine quantification, flow cytometry, pathway rescue with a pharmacological activator, and in vivo validation, exemplifies the rigorous architecture that transforms a plant-derived molecule into a credible drug lead. For a disease that continues to challenge urologists with recurrence and immune evasion, trifolirhizin now offers a scientifically grounded reason for excitement, and a clear mechanistic road map for the therapies that may follow it.

The choice of T24 and UMUC3 as experimental platforms deserves brief elaboration, since these cell lines embody distinct molecular subtypes of bladder carcinoma. T24 cells are derived from a transitional cell carcinoma and display a highly aggressive, invasive phenotype, while UMUC3 carries activating mutations in the HRAS oncogene, a lesion that sits squarely upstream of the PI3K/AKT cascade. The fact that trifolirhizin suppressed AKT phosphorylation and produced comparable IC50 values in both lines suggests its activity does not depend on a single driver mutation, a property that would broaden its potential applicability across molecularly diverse tumors.

The immune findings also fit into a larger conceptual shift in oncology. For decades, cytotoxic chemotherapy was viewed as inherently immunosuppressive, but it is now understood that certain agents can provoke immunogenic cell death, releasing tumor antigens and inflammatory signals that recruit cytotoxic T lymphocytes. The observed rise in interferon-gamma and the heightened susceptibility of treated cells to CD8-positive T cell killing are consistent with this paradigm, raising the possibility that trifolirhizin could act synergistically with immune checkpoint inhibitors, though such combinations remain untested in this study.

Methodologically, the use of SC79 as a pathway rescue tool reflects a standard of mechanistic proof increasingly expected in natural product research, where compounds often have many off-target effects. By demonstrating that forced AKT reactivation reverses the drug’s phenotypic effects, the authors substantially narrow the causal interpretation. Nevertheless, the study does not identify the direct molecular target of trifolirhizin upstream of AKT, leaving open whether the compound binds AKT itself, an upstream activator, or some other regulator of the cascade. Future work with target-identification techniques such as affinity pull-down or thermal proteome profiling would help resolve this question and clarify whether the high micromolar potency can be improved through rational chemical optimization of the pterocarpan scaffold.

Subject of Research: The anticancer effects of the natural flavonoid trifolirhizin on bladder carcinoma via modulation of the AKT/NF-κB signaling pathway

Article Title: Trifolirhizin induces apoptosis and suppresses proliferation, invasion and immune evasion in bladder cancer via AKT/NF-κB signaling pathway

Article References: Liu, D., Deng, G., Yang, H., & Zhang, Q. (2026). Trifolirhizin induces apoptosis and suppresses proliferation, invasion and immune evasion in bladder cancer via AKT/NF-κB signaling pathway. BioMedical Engineering OnLine. https://doi.org/10.1186/s12938-026-01613-7

Image Credits: AI Generated

DOI: 10.1186/s12938-026-01613-7

Keywords: bladder cancer, trifolirhizin, apoptosis, AKT/NF-κB pathway, immune evasion, cell proliferation, invasion, vimentin, E-cadherin, CD8-positive T cells, interferon-gamma, xenograft models

The immune system constantly patrols the body for abnormal cells, including cancer cells. Among its most powerful weapons are CD8-positive cytotoxic T cells, which recognize tumor-associated signals and can directly destroy malignant cells. Gastric tumors, however, often create an immunosuppressive environment that prevents these lymphocytes from functioning properly. Immune checkpoint inhibitors, or ICIs, are designed to release some of the molecular brakes placed on T cells, but their success depends heavily on the signals already operating inside the tumor.

D-serine belongs to a group of molecules known as D-amino acids. Most amino acids used to build proteins in humans are L-amino acids, while D-amino acids are their mirror-image forms, or enantiomers. Although D-amino acids were once considered biologically insignificant, scientists now know that they can occur naturally in body fluids and may originate from food, intestinal microbes, or cellular metabolism. D-serine is already recognized for its role in nervous-system signaling, but the Keio team investigated whether it could also influence cancer immunity.

The researchers used mouse models of gastric cancer and introduced different D-amino acids and their corresponding L-amino acids into tumors. Among the compounds tested, only D-serine produced a clear increase in tumor growth compared with untreated controls. Detailed analysis showed that the molecule was not simply feeding the cancer cells. Instead, it altered the immune ecosystem surrounding the tumors, increasing the abundance and activity of anti-inflammatory immune cells, especially M2-like macrophages.

Macrophages are highly adaptable immune cells that can either attack tumors or support their growth, depending on the chemical signals around them. In the D-serine-treated tumors, macrophages acquired a tumor-promoting, immunosuppressive profile. At the same time, the number of CD8-positive cytotoxic T cells fell, and the T cells that remained showed markedly reduced activity. This combination—more suppressive macrophages and fewer functional killer T cells—created conditions that allowed gastric tumors to expand with less immune resistance.

The team then examined the molecular secretions of tumor-associated macrophages, commonly called TAMs. In tumors exposed to D-serine, these cells released unusually high amounts of fibronectin 1, or FN1, and secreted phosphoprotein 1, known as SPP1 or osteopontin. Both molecules have been associated with immune regulation and tumor progression. In this setting, they appeared to contribute to the suppression of CD8-positive T cells, helping the tumor maintain an immune-protected niche.

One experiment provided evidence that SPP1 was an important part of this pathway. When the researchers administered antibodies designed to neutralize SPP1 in D-serine-enhanced tumors, tumor growth slowed and approached the rate observed in mice with lower D-serine activity. The result suggests that D-serine may operate upstream of a signaling cascade in which macrophages release SPP1 and FN1, ultimately weakening the T-cell response. However, the findings do not yet establish that blocking SPP1 or D-serine will be effective as a treatment in people.

To investigate whether the mouse findings might have clinical relevance, the researchers analyzed patient data from several human cohorts. Patients with gastric cancer had higher serum D-serine concentrations than healthy controls. The highest levels were detected in people with stage IV disease whose tumors had resisted ICI treatment. This association raises the possibility that a blood test for D-serine could help identify patients whose tumors are more likely to evade immunotherapy, although larger prospective studies will be needed before such testing can guide clinical decisions.

The findings are particularly significant because ICIs are increasingly used as first-line treatment for advanced gastric cancer, yet responses vary widely and treatment can cause immune-related adverse events. Measuring D-serine in blood, and potentially in stool, could offer a way to assess the tumor’s immunological state before therapy begins. The researchers are now examining whether D-serine levels can predict treatment response and whether intestinal bacteria responsible for producing the molecule contribute to its accumulation. If future studies confirm the mechanism, therapies aimed at reducing D-serine or interrupting its downstream signals could provide a new strategy for restoring anti-tumor immunity. For now, the work identifies D-serine as a promising biomarker and a potential immune-regulatory target, but its therapeutic value remains to be tested in human clinical trials.

Subject of Research: Animals

Article Title: D-serine as a metabolic immune checkpoint in the tumour microenvironment

News Publication Date: 31-Jul-2026

Web References: https://doi.org/10.1016/j.ebiom.2026.106402; https://www.keio-sujino-lab.com/; https://researchmap.jp/tsujino

References: https://doi.org/10.1016/j.ebiom.2026.106402

Image Credits: Shohei Suzuki and Tomohisa Sujino, Keio University, Japan

Keywords: D-serine, gastric cancer, tumor immunity, immune checkpoint inhibitors, immunotherapy resistance, tumor-associated macrophages, CD8-positive T cells, SPP1, FN1, metabolic immune checkpoint