👤 Marc Boutros

Osteosarcoma remains the most common primary malignant bone tumor, with poor outcomes in metastatic or recurrent cases. Current treatments often fail to prevent relapse, highlighting the need for innovative therapeutic strategies. Aptamers, short and single-stranded oligonucleotides capable of folding into three-dimensional shapes, have emerged as promising tools for targeted cancer diagnostics and therapy due to their high affinity, specificity, and modifiability. A structured search was conducted through PubMed, Scopus, and Google Scholar up to March 2025, focusing on peer-reviewed articles exploring the use of aptamers in osteosarcoma. A total of 158 studies were included, highlighting aptamer applications in tumor diagnosis, pathway targeting, and precision drug delivery. Aptamers demonstrated significant potential in osteosarcoma research, notably in identifying tumorigenesis pathways, enhancing diagnostic accuracy through ELISA and biosensors, and improving targeted drug delivery. SELEX-derived aptamers effectively targeted molecules such as CD133, EGFR, VEGFA, and FGFR1, leading to enhanced cytotoxicity, reduced off-target effects, and greater specificity for osteosarcoma cells and cancer stem cells. The integration of aptamers with nanoparticles further optimized therapeutic delivery, highlighting their capability to enhance precision medicine in osteosarcoma. Aptamers offer clear benefits over traditional osteosarcoma treatments. Their strong binding affinity to cancer cells, low risk of immune reactions, and flexible chemical modifications make them powerful tools for diagnosis and therapy, especially when combined with nanoparticle delivery systems. Aptamers represent a promising class of targeted agents for osteosarcoma. Future research should prioritize optimizing delivery strategies and validating clinical efficacy to accelerate their integration into clinical practice. Show less

Cells rely on a diverse repertoire of genes for maintaining homeostasis, but the transcriptional networks underlying their expression remain poorly understood. The MOF acetyltransferase-containing Non-Specific Lethal (NSL) complex is a broad transcription regulator. It is essential in Drosophila, and haploinsufficiency of the human KANSL1 subunit results in the Koolen-de Vries syndrome. Here, we perform a genome-wide RNAi screen and identify the BET protein BRD4 as an evolutionary conserved co-factor of the NSL complex. Using Drosophila and mouse embryonic stem cells, we characterise a recruitment hierarchy, where NSL-deposited histone acetylation enables BRD4 recruitment for transcription of constitutively active genes. Transcriptome analyses in Koolen-de Vries patient-derived fibroblasts reveals perturbations with a cellular homeostasis signature that are evoked by the NSL complex/BRD4 axis. We propose that BRD4 represents a conserved bridge between the NSL complex and transcription activation, and provide a new perspective in the understanding of their functions in healthy and diseased states. Show less

In colorectal cancer (CRC), aberrant Wnt signalling is essential for tumorigenesis and maintenance of cancer stem cells. However, how other oncogenic pathways converge on Wnt signalling to modulate stem cell homeostasis in CRC currently remains poorly understood. Using large-scale compound screens in CRC, we identify MEK1/2 inhibitors as potent activators of Wnt/β-catenin signalling. Targeting MEK increases Wnt activity in different CRC cell lines and murine intestine in vivo. Truncating mutations of APC generated by CRISPR/Cas9 strongly synergize with MEK inhibitors in enhancing Wnt responses in isogenic CRC models. Mechanistically, we demonstrate that MEK inhibition induces a rapid downregulation of AXIN1. Using patient-derived CRC organoids, we show that MEK inhibition leads to increased Wnt activity, elevated LGR5 levels and enrichment of gene signatures associated with stemness and cancer relapse. Our study demonstrates that clinically used MEK inhibitors inadvertently induce stem cell plasticity, revealing an unknown side effect of RAS pathway inhibition. Show less

Tienilic acid (TA) was withdrawn due to idiosyncratic hepatotoxicity. Two hypotheses for the mechanisms of idiosyncratic reactions are the hapten and danger hypotheses, which are not mutually exclusive. Both human CYP 2C9 and rat CYP 2C11 metabolize TA to a reactive metabolite that was reported to bind exclusively to these enzymes. TA-Induced liver toxicity is associated with antibodies against CYP 2C9, thus TA appears to act as a hapten. However, if the binding were limited to CYP 2C, it is unlikely that this would lead to significant cell stress. If TA does not cause cell stress it would suggest that acting as a hapten is sufficient to induce an idiosyncratic reaction. To test whether TA can cause cell stress rats were dosed with TA and hepatic gene expression was profiled at 6 and 24 hr after drug administration. TA induced changes in genes involved in oxidative stress (aldo-keto reductase, glutathione-S-transferase, thioredoxin reductase, epoxide hydrolase), inflammation (IL-1beta, interferon regulatory factor 1, macrophage stimulating protein 1), cytotoxicity (caspase-12), and liver regeneration (p27(Kip1), DUSP6, serine dehyratase, spectrin beta II, inhibin beta(A)). These data support the hypothesis that danger signals in the form of cell-stress may be involved in initiating the immune response observed in TA-induced toxicity. In separate experiments, we examined the changes in gene expression induced in mice by sulfamethoxazole, which also causes idiosyncratic reactions. Sulfamethoxazole is an aromatic amine, and aromatic amines in general are associated with idiosyncratic drug reactions. They form reactive metabolites that both act as electrophiles and can redox cycle; therefore, it was assumed that sulfamethoxazole would cause some type of cell stress, the only question was what changes in mRNA expression would occur. In contrast to expectations, no changes induced by sulfamethoxazole could easily be interpreted as a danger signal. These data are presented together because they are the opposite of the expected results and convey a complex story. Show less