The new study, published in the journal Molecular Cell and led by Johnathan R. Whetstine, director of the Cancer Epigenetics Institute, demonstrates that gene copy-number amplification, long viewed as a random byproduct of genomic chaos, is in fact a biologically regulated process governed by specific chromatin machinery. By identifying the enzymatic gatekeepers that control how MYC amplification begins and progresses, the team has opened a potential therapeutic route that sidesteps the protein entirely and instead constrains the DNA structural events that multiply the gene. According to Whetstine, this strategy of targeting the DNA structural assembly line rather than the finished protein could have relevance for at least 30 percent of all cancers.

The technical heart of the discovery lies in two chromatin-regulating proteins, KDM4C and SETD2, which the researchers found act as gatekeepers controlling access to the MYC gene region. SETD2 is a histone methyltransferase that helps maintain a stable, properly marked chromatin environment, while KDM4C is a histone demethylase that remodels the epigenetic landscape. Under normal conditions, these enzymes help keep DNA packaged and regulated within the cell. But when SETD2 is lost or blocked, KDM4C gains improper access to the MYC locus and alters the surrounding DNA environment. Tumors, the team found, frequently increase KDM4C levels, which further drives the deleterious amplification process.

Using human cell models, genomic analyses, and mouse studies, the researchers showed that KDM4C does more than loosen chromatin. It actively recruits the cell’s DNA-copying machinery to the MYC region, causing the gene to be copied repeatedly and generating extra MYC copies. The effect was not circumstantial. In a striking proof of causality, the team used dCas9 technology to direct KDM4C to the MYC region artificially, and that alone was sufficient to trigger amplification, even in cells with a completely normal set of chromosomes. As Benjamin I. Ferman, a PhD student in the Whetstine lab and first author of the study, explained, the findings demonstrate that MYC amplification is not simply a random byproduct of genomic instability, but a process actively controlled by specific epigenetic programs.

Copying MYC, however, is only half the story. The real danger emerges when cells carrying dangerous levels of MYC fail to eliminate themselves. MYC overactivation normally triggers programmed cell death, a built-in safeguard against runaway proliferation. The researchers found that disabling this fail-safe allowed hyperamplification and tumor formation to proceed. When cells lost their normal ability to undergo apoptosis, abnormal MYC amplifications could reach high levels and continue expanding. This effect was especially pronounced when cells also lost TP53, a crucial tumor suppressor gene that normally helps eliminate damaged cells before they can do harm.

Over time, the combination of disrupted epigenetic control and TP53 loss drove MYC amplification to high levels, including the formation of circular extrachromosomal DNA, a notoriously aggressive form of oncogene amplification that can accelerate tumor evolution and drug resistance. In mouse models, the consequences were decisive: the starting cells were non-transformed and did not cause tumors without MYC amplification, but once the epigenetic program ran its course and cellular defenses failed, tumor formation followed. The findings suggest that MYC amplification develops in stages, with chromatin changes first triggering the formation of extra gene copies, and the failure of normal defense mechanisms then allowing those abnormal cells to survive, spread, and grow more aggressive. Whetstine notes that this staged relationship echoes the Two-Hit Theory of cancer causation, the landmark concept originated at Fox Chase by Alfred Knudson.

The translational implications are significant. Because the newly identified regulatory mechanisms contain enzymatic targets, they could in principle be exploited through small-molecule drug development, opening therapeutic avenues for MYC-driven cancers that have resisted every conventional approach. The Whetstine lab found that blocking KDM4C activity, either genetically or with targeted drugs, reduced MYC amplification across multiple experimental systems, including MYC-amplified cancer cells and animal models. Notably, a clinically used KDM4 inhibitor successfully suppressed MYC amplification in vivo, an early proof of concept that a challenge long considered untouchable may be addressable in the clinic.

Beyond drug development, the work points to a new biomarker paradigm. If specific epigenetic imbalances, such as SETD2 loss combined with elevated KDM4C, reliably predict which tumors are poised to develop aggressive amplification states, clinicians could potentially identify high-risk cancers earlier and intervene before extrachromosomal DNA and treatment resistance take hold. Whetstine emphasized that MYC amplification appears to be far more dynamic and controlled than previously appreciated, raising the possibility that these amplification states could be therapeutically constrained rather than simply endured. Biomarker and therapeutic studies are already under development at the Cancer Epigenetics Institute and Fox Chase.

The research was supported by the National Institutes of Health and developmental funding from Fox Chase Cancer Center. In addition to the Fox Chase team, collaborators from Massachusetts General Hospital, Harvard Medical School, Stanford University, the Broad Institute, and the Icahn School of Medicine at Mount Sinai contributed to the study. Taken together, the findings reframe one of cancer biology’s oldest puzzles: the amplification of a master growth gene is not a stochastic accident but a regulated epigenetic program with identifiable switches, and those switches, unlike the MYC protein itself, may finally be druggable.

Subject of Research: Epigenetic regulation of MYC gene amplification in aggressive cancers

Article Title: Cracking the 'undruggable' code: Fox Chase Cancer Center researchers unveil epigenetic blueprint fueling aggressive MYC amplification driving cancer

Article References: Cracking the 'undruggable' code: Fox Chase Cancer Center researchers unveil epigenetic blueprint fueling aggressive MYC amplification driving cancer. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: MYC, gene amplification, epigenetics, KDM4C, SETD2, extrachromosomal DNA, TP53, chromatin, undruggable targets, Fox Chase Cancer Center, Molecular Cell, cancer therapy

The clinical stakes are considerable. Renal cell carcinoma accounts for roughly 3.8 percent of adult cancer diagnoses, and clear cell carcinoma represents about 75 percent of those cases. According to the 2023 Cancer Statistics Report, the United States was projected to see 81,800 new kidney cancer cases and 14,890 deaths. Surgery remains the mainstay of treatment, but more than half of patients develop metastasis after nephrectomy, and the five-year survival rate for metastatic disease languishes below 12 percent. Against this grim backdrop, the search for molecular markers that can stratify risk and reveal actionable vulnerabilities has taken on real urgency.

RPL28 belongs to a family of proteins that assemble into ribosomes, the molecular factories that translate messenger RNA into protein. Eukaryotic ribosomes comprise a large 60S subunit containing roughly 46 ribosomal proteins and a small 40S subunit with about 33 more. Yet ribosomal proteins are increasingly recognized as multitaskers, engaging in extraribosomal functions that include regulating proliferation, apoptosis, DNA repair, and cell cycle control. Recent work has implicated them in tumorigenesis across multiple cancers, and the new study asked whether RPL28, located on chromosome 19q13.42, plays a similar role in kidney cancer, whose distinct molecular landscape of VHL-driven pseudohypoxia, metabolic reprogramming, and frequent chromosome 3p alterations could give ribosomal components entirely different significance than in colorectal or liver tumors, where RPL28 had previously drawn attention.

The researchers began by mining RNA sequencing data from The Cancer Genome Atlas, comparing 535 clear cell renal cell carcinoma specimens with 72 adjacent normal kidney tissues. RPL28 expression was markedly elevated in the tumors, a finding independently confirmed in the International Cancer Genome Consortium’s RECA-EU cohort of 91 tumors and 45 normal samples. Crucially, the team also validated the result at the protein level, using immunohistochemistry on paired tumor and normal tissue from 12 patients treated at Meizhou People’s Hospital, where the mean patient age was 62.3 years. A pan-cancer survey through the TIMER2.0 database further revealed RPL28 overexpression in breast, bladder, colon, liver, and lung cancers, positioning the protein as a broad marker of malignant behavior.

When the TCGA cohort was split into high- and low-expression groups at the median, the differences were striking. Elevated RPL28 correlated significantly with male sex, tumor presence, higher histological grade, advanced T stage, distant metastasis, and advanced TNM stage. Survival analysis drove the point home: patients with high RPL28 expression had significantly worse overall survival, with a hazard ratio of 1.5, and worse disease-specific survival, with a hazard ratio of 1.9. Multivariate Cox regression confirmed that RPL28 expression stood as an independent prognostic factor alongside histological grade and TNM stage. The team then built nomograms incorporating RPL28 to predict one-, three-, and five-year survival, achieving area under the curve values of 0.856, 0.798, and 0.753 respectively, outperforming any single clinical factor in both ROC and decision curve analyses.

The study also probed how RPL28 relates to the molecular subtypes defined by kidney cancer’s characteristic driver mutations. Among the genes examined, including VHL, PBRM1, BAP1, KDM5C, MTOR, TP53, PTEN, PIK3CA, and ARID1A, only SETD2 showed a significant association, with RPL28 expression significantly higher in SETD2-mutant tumors. Because SETD2 regulates chromatin and transcription, the authors caution that this exploratory finding is hypothesis-generating rather than proof of direct regulation, but it hints that RPL28 overexpression may arise within a specific epigenetic context rather than being a generic byproduct of the common 3p deletions that dominate the disease.

Given that clear cell renal cell carcinoma is among the most immune-infiltrated solid tumors and responds clinically to immunotherapy, the researchers examined whether RPL28 expression tracked with immune features. Using xCell algorithms adjusted for tumor purity, they found that RPL28-high tumors harbored significantly different levels of regulatory T cells, NKT cells, and mast cells. Checkpoint gene analysis added nuance: the RPL28-high group showed higher expression of PDCD1 and LAG3 but lower levels of CD274 and PDCD1LG2, the genes encoding PD-L1 and PD-L2. A pharmacogenomic analysis using CTRP-trained models further suggested that RPL28-high tumors might be more sensitive to several targeted agents, including axitinib, sunitinib, sorafenib, pazopanib, cabozantinib, and temsirolimus, though the authors stress these computational predictions await experimental validation.

The most compelling evidence came from the laboratory. The team silenced RPL28 in two clear cell renal cell carcinoma cell lines, 786-O and OSRC-2, using lentiviral short hairpin RNA, confirming efficient knockdown by quantitative PCR. Cell Counting Kit-8 assays showed that RPL28 silencing significantly impaired proliferation in both lines, while wound-healing assays, quantified over 24 hours in serum-reduced conditions to exclude proliferative effects, revealed a marked drop in migratory capacity. Gene set enrichment analysis supplied a mechanistic framework: elevated RPL28 expression was strongly associated with epithelial-mesenchymal transition, the developmental program that endows cancer cells with mobility and invasiveness, as well as with TGF-beta and MYC signaling, two pathways known to drive EMT. The correlation between RPL28 and EMT reached a coefficient of 0.335 and held across multiple cancer types in the pan-cancer analysis.

These results fit into a growing body of work showing that individual ribosomal proteins can steer cancer behavior. RPL23 has been linked to cisplatin resistance in ovarian cancer through EMT activation, RPS7 overexpression promotes growth and migration in prostate cancer, and RPL14 drives proliferation and invasion in nasopharyngeal carcinoma. The concept of ribosome heterogeneity, in which tumors assemble ribosomes with varying protein compositions to preferentially translate mRNAs supporting proliferation, stress adaptation, and therapeutic resistance, offers a plausible explanation for how a single ribosomal protein could exert such outsized influence in a tumor defined by metabolic and translational plasticity.

The authors are candid about the study’s limitations. Survival analyses rested primarily on a single cohort, immune infiltration was inferred computationally from bulk RNA sequencing, myeloid-derived suppressor cells were not directly estimated, drug sensitivity was predicted rather than tested, and the functional experiments were confined to cell cultures. Multicenter validation, in vivo models, and mechanistic dissection will be needed before RPL28 reaches the clinic. Nevertheless, the convergence of evidence, from overexpression in tumors to independent prognostic power to demonstrable effects on cancer cell proliferation and migration, makes RPL28 a rare example of a ribosomal component emerging as a credible biomarker and drug target in one of oncology’s most challenging cancers.

Subject of Research: The role of the ribosomal protein RPL28 in the progression, prognosis, and potential treatment of clear cell renal cell carcinoma

Article Title: Knockdown of RPL28 Inhibits the Progression of Clear Cell Renal Cell Carcinoma

Article References: Luo, R., Wu, G., Xie, Z., Xiao, Y., Zhu, W., & Jiang, H. (2026). Knockdown of RPL28 Inhibits the Progression of Clear Cell Renal Cell Carcinoma. Cancer Reports, 9(9), Article e70683. https://doi.org/10.1002/cnr2.70683

Image Credits: AI Generated

DOI: 10.1002/cnr2.70683

Keywords: RPL28, clear cell renal cell carcinoma, kidney cancer, ribosomal protein, prognostic biomarker, epithelial-mesenchymal transition, TCGA, SETD2, immune infiltration, drug sensitivity, TGF-beta signaling, MYC signaling