Krystina Szylo

All Publications

• Fin(e)-tuning ferroptosis. Molecular cell Szylo, K. J., Dixon, S. J. 2026; 86 (2): 234-236

  Abstract

  In a recent issue of Cell, Lorenz et al.1 report that the anti-ferroptosis protein GPX4 anchors to membranes using a unique "fin-loop" element that is disrupted in an ultrarare human disease, decoupling enzyme activity from biological function and causing neurodegeneration.

  View details for DOI 10.1016/j.molcel.2025.12.030

  View details for PubMedID 41576911

• Adipose tissue explant culture using PDMS flow chambers: an alternative to static explant culture. Adipocyte Cohen, M., Bandaru, P., Szylo, K., Nguyen, N., Nadeak, B., Paszkiewicz, R., Ashby, J. W., Mack, J. J., Tanaka, L., Tan, J., Khademhosseini, A., Mittelman, S. D. 2025; 14 (1): 2578286

  Abstract

  As obesity rates continue to rise, it is important that we can effectively study adipose tissue to understand its physiological contribution in individuals with obesity. Unfortunately, due to the fragility and buoyancy of adipose tissue, culture remains challenging. Ex vivo culture of tissue explants is possible, however after 48 hours explants often display declining viability, increased inflammation, and de-differentiation. Other common approaches include differentiation of preadipocytes and adipocyte isolation by enzymatic dissociation, however these methods are time-consuming and fail to recapitulate the structure and cellular network within adipose tissue. Given these shortcomings, we developed a novel explant culture method using polydimethylsiloxane (PDMS) flow chambers attached to a micro peristaltic pump. This approach reduces air interface while enabling media perfusion, time-resolved measurements of secreted factors, and easy incorporation of treatments. Using our chambers, we assessed viability with resazurin and lactate dehydrogenase (LDH) assays, physiology by measuring glycerol release, architecture by confocal imaging, and retention of adipose gene expression by qPCR. Explants remained viable for over 72 hours. Resazurin reduction was at 84 ± 9% of baseline, and LDH release remained low. Isoproterenol treatment resulted in 2.7 ± 0.5-fold increased glycerol release, while insulin returned release to baseline. Confocal imaging showed preserved architecture, while qPCR of human tissue with insulin and dexamethasone supplementation showed maintained expression of PPARG and FABP4 over 72 hours. Overall, our results suggest PDMS flow chambers are a suitable method for adipose explant culture that requires minimal processing, making this system a viable option for translational research.

  View details for DOI 10.1080/21623945.2025.2578286

  View details for PubMedID 41132053

  View details for PubMedCentralID PMC12562731

• Lymph node environment drives FSP1 targetability in metastasizing melanoma. Nature Palma, M., Chaufan, M., Breuer, C. B., Müller, S., Sabatier, M., Fraser, C. S., Szylo, K. J., Yavari, M., Carmona, A., Kaur, M., Melo, L. M., Cansiz, F., Monge-Lorenzo, J., Flores, M., Mishima, E., Nakamura, T., Proneth, B., Labrado, M., Liang, Y., Cayting, N., Zheng, L., Cañeque, T., Colombeau, L., Wahida, A., Friedmann Angeli, J. P., Tasdogan, A., Hui, S., Rodriguez, R., Conrad, M., Reticker-Flynn, N. E., Ubellacker, J. M. 2025

  Abstract

  Ferroptosis has emerged as an actionable target to eliminate therapy-resistant and metastatic cancers1. However, which ferroptosis surveillance systems may offer a therapeutic window to leverage redox maladaptation in cancer remains unclear. In melanoma, glutathione peroxidase 4 (GPX4) impedes ferroptosis during haematogenous metastasis, but is dispensable during lymphatic metastasis2. Here, using a metastatic mouse melanoma model selected for lymph node metastasis, we show that lymph-node-derived metastatic cells exhibit markedly diminished expression of glutamate-cysteine ligase (GCLC) and reduced glutathione (GSH) levels relative to their parental counterparts. This metabolic shift occurs within the hypoxic lymphatic niche. Under comparable low-oxygen conditions, GPX4 undergoes ubiquitination and proteasomal degradation. In response, lymph node metastatic cells acquire increased reliance on ferroptosis suppressor protein 1 (FSP1), which is localized with perinuclear lysosomes. These findings reveal that the reduced reliance on the GPX4 axis enables melanoma cells to shift toward FSP1 dependency. Notably, intratumoural monotherapy with selective FSP1 inhibitors (viFSP1 and FSEN1) effectively suppresses melanoma growth in lymph nodes, but not in subcutaneous tumours, emphasizing a microenvironment-specific dependency on FSP1. Thus, targeting FSP1 in the lymph nodes holds strong potential for blocking melanoma progression.

  View details for DOI 10.1038/s41586-025-09709-1

  View details for PubMedID 41193799

  View details for PubMedCentralID 9273022

• Activation of lysosomal iron triggers ferroptosis in cancer. Nature Cañeque, T., Baron, L., Müller, S., Carmona, A., Colombeau, L., Versini, A., Solier, S., Gaillet, C., Sindikubwabo, F., Sampaio, J. L., Sabatier, M., Mishima, E., Picard-Bernes, A., Syx, L., Servant, N., Lombard, B., Loew, D., Zheng, J., Proneth, B., Thoidingjam, L. K., Grimaud, L., Fraser, C. S., Szylo, K. J., Der Kazarian, E., Bonnet, C., Charafe-Jauffret, E., Ginestier, C., Santofimia-Castaño, P., Estaras, M., Dusetti, N., Iovanna, J. L., Cunha, A. S., Pittau, G., Hammel, P., Tzanis, D., Bonvalot, S., Watson, S., Gandon, V., Upadhyay, A., Pratt, D. A., Freitas, F. P., Friedmann Angeli, J. P., Stockwell, B. R., Conrad, M., Ubellacker, J. M., Rodriguez, R. 2025; 642 (8067): 492-500

  Abstract

  Iron catalyses the oxidation of lipids in biological membranes and promotes a form of cell death called ferroptosis1. Defining where this chemistry occurs in the cell can inform the design of drugs capable of inducing or inhibiting ferroptosis in various disease-relevant settings. Genetic approaches have revealed suppressors of ferroptosis2-4; by contrast, small molecules can provide spatiotemporal control of the chemistry at work5. Here we show that the ferroptosis inhibitor liproxstatin-1 exerts cytoprotective effects by inactivating iron in lysosomes. We also show that the ferroptosis inducer RSL3 initiates membrane lipid oxidation in lysosomes. We designed a small-molecule activator of lysosomal iron-fentomycin-1-to induce the oxidative degradation of phospholipids and ultimately ferroptosis. Fentomycin-1 is able to kill iron-rich CD44high primary sarcoma and pancreatic ductal adenocarcinoma cells, which can promote metastasis and fuel drug tolerance. In such cells, iron regulates cell adaptation6,7 while conferring vulnerability to ferroptosis8,9. Sarcoma cells exposed to sublethal doses of fentomycin-1 acquire a ferroptosis-resistant cell state characterized by the downregulation of mesenchymal markers and the activation of a membrane-damage response. This phospholipid degrader can eradicate drug-tolerant persister cancer cells in vitro and reduces intranodal tumour growth in a mouse model of breast cancer metastasis. Together, these results show that control of iron reactivity confers therapeutic benefits, establish lysosomal iron as a druggable target and highlight the value of targeting cell states10.

  View details for DOI 10.1038/s41586-025-08974-4

  View details for PubMedID 40335696

  View details for PubMedCentralID PMC12158755

• Selenoprotein O Promotes Melanoma Metastasis and Regulates Mitochondrial Complex II Activity. Cancer research Nascentes Melo, L. M., Sabatier, M., Ramesh, V., Szylo, K. J., Fraser, C. S., Pon, A., Mitchell, E. C., Servage, K. A., Allies, G., Westedt, I. V., Cansiz, F., Krystkiewicz, J., Kutritz, A., Schadendorf, D., Morrison, S. J., Ubellacker, J. M., Sreelatha, A., Tasdogan, A. 2025; 85 (5): 942-955

  Abstract

  Evolutionarily conserved selenoprotein O (SELENOO) catalyzes a posttranslational protein modification known as AMPylation that is essential for the oxidative stress response in bacteria and yeast. Given that oxidative stress experienced in the blood limits survival of metastasizing melanoma cells, SELENOO might be able to affect metastatic potential. However, further work is needed to elucidate the substrates and functional relevance of the mammalian homolog of SELENOO. In this study, we revealed that SELENOO promotes cancer metastasis and identified substrates of SELENOO in mammalian mitochondria. In patients with melanoma, high SELENOO expression was correlated with metastasis and poor overall survival. In a murine model of spontaneous melanoma metastasis, SELENOO deficiency significantly reduced metastasis to distant visceral organs, which could be rescued by treatment with the antioxidant N-acetylcysteine. Mechanistically, SELENOO AMPylated multiple mitochondrial substrates, including succinate dehydrogenase subunit A, one of the four key subunits of mitochondrial complex II. Consistently, SELENOO-deficient cells featured increased mitochondrial complex II activity. Together, these findings demonstrate that SELENOO deficiency limits melanoma metastasis by modulating mitochondrial function and oxidative stress. Significance: SELENOO alters mitochondrial function and supports metastasis in melanoma, highlighting the impact of SELENOO-mediated posttranslational modification of mitochondrial substrates and selenoproteins in cancer progression.

  View details for DOI 10.1158/0008-5472.CAN-23-2194

  View details for PubMedID 39700395

  View details for PubMedCentralID PMC11873727

• Advancements in melanoma cancer metastasis models. Pigment cell & melanoma research Nascentes Melo, L. M., Kumar, S., Riess, V., Szylo, K. J., Eisenburger, R., Schadendorf, D., Ubellacker, J. M., Tasdogan, A. 2023; 36 (2): 206-223

  Abstract

  Metastatic melanoma is a complex and deadly disease. Due to its complexity, the development of novel therapeutic strategies to inhibit metastatic melanoma remains an outstanding challenge. Our ability to study metastasis is advanced with the development of in vitro and in vivo models that better mimic the different steps of the metastatic cascade beginning from primary tumor initiation to final metastatic seeding. In this review, we provide a comprehensive summary of in vitro models, in vivo models, and in silico platforms to study the individual steps of melanoma metastasis. Furthermore, we highlight the advantages and limitations of each model and discuss the challenges of how to improve current models to enhance translation for melanoma cancer patients and future therapies.

  View details for DOI 10.1111/pcmr.13078

  View details for PubMedID 36478190