Evaluating temozolomide for pediatric adamantinomatous craniopharyngiomas using microspheroid-based drug screening Sérgio Cavalheiro, Lorena Favaro Pavon, Caroline Brunetto de Farias, Nasjla Saba da Silva, Flávia Borelli Nascimento, Tatiana Tais Sibov, Jessica Benigno Rodrigues, Patrícia Alesssandra Dastoli, Fernando Seiji Suzuki, Rodrigo Akira Watanabe, Isaque Hyung Tong Kim, Martina Lichtenfels, Camila Alves da Silva, Andrea Cappellano, Marcos Devanir Silva da Costa Child S Nervous System, 2026 Purpose Pediatric adamantinomatous craniopharyngioma (ACP) is the most common tumor of the diencephalic–pituitary axis in children. Although histologically benign, pediatric ACP is frequently associated with substantial endocrine dysfunction and neurological complications. The gold-standard treatment is complete surgical resection; however, because of the tumor’s location, total removal is often not feasible. Consequently, several authors recommend radiotherapy as an adjuvant option. Nevertheless, partial resections are frequently followed by recurrence, and repeated surgical interventions increase morbidity and impair quality of life. Thus, adjuvant therapeutic strategies capable of controlling this tumor should be encouraged. Methods We analyzed seven fresh tumor specimens ACP from patients < 18 years of age using a chemoresistance platform ( Bioverso Test , Ziel Biosciences , São Paulo, Brazil). These cases demonstrated widespread resistance to most chemotherapeutic agents tested. Temozolomide (500 µM) was the only drug that showed consistent and significant sensitivity. Results Based on these findings, we initiated treatment in a 14-year-old patient with recurrent ACP who had previously undergone multiple surgical procedures and radiotherapy. The tumor involved the left cavernous sinus and extended into the sphenoid sinus. Clinically, the patient was amaurotic and presented with panhypopituitarism. The patient received temozolomide (200 mg/m 2 /day for 5 consecutive days in 28-day cycles). After completing 12 cycles of chemotherapy, there was a notable regression of the lesion, with approximately 50% reduction in total tumor volume. Conclusion These findings suggest that temozolomide may represent a promising therapeutic option for controlling ACP.
The GRPR signaling axis in cancer: Molecular mechanisms and oncogenic outcomes Júlia Caroline Marcolin, Martina Lichtenfels, Rafael Roesler, Caroline Brunetto de Farias Cellular Signalling, 2026 The gastrin-releasing peptide (GRP) and its receptor (GRPR) constitute a biologically versatile signaling axis with essential physiological roles and growing relevance in cancer biology. GRPR is frequently expressed across multiple tumor types, where its activation modulates key cellular processes associated with malignant progression. Through engagement of diverse intracellular effectors and extensive crosstalk with receptor tyrosine kinases and other signaling systems, GRPR regulates pathways controlling tumor cell proliferation, survival, migration, invasion, angiogenesis, and transcriptional reprogramming. This review provides a comprehensive overview of the molecular mechanisms underlying GRPR-mediated signaling in cancer, integrating evidence from different tumor models. Importantly, the antitumor effects observed following pharmacological inhibition or genetic silencing of GRPR further underscore its therapeutic relevance. Collectively, these findings position GRPR as a central signaling integrator in tumor progression and a promising target for diagnostic, prognostic, and therapeutic strategies in oncology.
The gastrin-releasing peptide receptor as a potential biomarker for squamous cell carcinoma Danielly Brufatto Olguins, Júlia Caroline Marcolin, Mariane da Cunha Jaeger, Manoela Domingues Martins, Luis Fernando da Rosa Rivero, Gilberto Schwartsmann, Rafael Roesler, Marcelo Gerardin Poirot Land, Martina Lichtenfels, Caroline Brunetto de Farias Scientific Reports, 2025 The gastrin-releasing peptide receptor (GRPR) is expressed across multiple human cancer types, including head and neck tumors, and has also been detected in the oral mucosa of patients bearing head and neck neoplasms. This study aimed to evaluate GRPR expression in tumor samples obtained from patients with histopathologically confirmed squamous cell carcinomas of the head and neck and esophagus. GRPR protein expression was analyzed by immunohistochemistry in 80 tumor specimens and 10 cancer-free tissue samples. GRPR positivity was observed in 72.5% of tumors, whereas all healthy control samples were negative. Additionally, an expression threshold of 10% was sufficient to distinguish between positive and negative tumors ( P < 0.0001). Overall survival for the cohort was 64.7%. GRPR expression tends to influence patient outcomes, with an expression level exceeding 50% correlating with worse survival ( p = 0.031). GRPR is overexpressed in head and neck and esophageal squamous cell carcinoma, and higher expression was associated with worse survival, suggesting a promising role of GRPR as a new biomarker for early diagnosis and prognosis.
Pathologic and Molecular Diagnosis of Ewing Sarcoma: A Multicenter Analysis From the Latin American Cooperative Group Trial André T. Brunetto, Lauro J. Gregianin, Marialva Sinigaglia, Julie F.C.S. Pestilho, Adriana Rose, Milena Villarroel, Luis Castillo, Maria de Los Angeles, Caroline B. de Farias, Jessica M. Lopez Marti, Elisa Alcalde, Luis F. da Rosa Rivero, Rafael Roesler, and Journal of Pediatric Hematology Oncology, 2025 Introduction: Ewing Sarcoma (ES) is a small, round, blue cell tumor (SRBCT) characterized by a chromosomal translocation between chromosomes 11 and 22 in ~85% of cases, alongside immunohistochemical (IHC) expression of the surface glycoprotein CD99. Despite advancements in molecular diagnostics, low-income countries continue to face challenges in tumor classification and identification of fusion partners. Methods: This study retrospectively analyzed pathology reports from 396 patients enrolled in the Latin American Cooperative Group (GALOP) trial, with data collected until December 2021. CD99 positivity or molecular confirmation of EWSR1 translocation were required for inclusion. Results: IHC marker selection varied across pathology units, reflecting differences in national guidelines. FLI1 was assessed in 45.5% of cases, VIM in 40.4%, and NKX2-2 in 14.9%. The most common complementary markers included desmin (60.1%), myogenin (47.5%), LCA/CD45 (51.5%), and synaptophysin (44.9%). EWSR1 translocation confirmation was performed in 74 patients (18.6%) using FISH and/or PCR. Molecular testing was more frequent in Argentina (73%), while Brazil, Chile, and Uruguay reserved it for diagnostically uncertain cases. Ki-67 was assessed in 70 cases, with most showing a high proliferation index (>30%). Conclusion: These findings underscore the need for continued collaboration to standardize diagnostic approaches across Latin America, aiming to improve treatment outcomes for ES patients.
Neurotrophins as Potential Biomarkers for Active Disease and Poor Outcome in Pediatric Acute Lymphoblastic Leukemia Karine Pereira de Andrade, Gustavo Lovatto Michaelsen, Lívia Fratini Dutra, Rebeca Ferreira Marques, Daniela Elaine Roth Benincasa, Júlia Plentz Portich, Jiseh Fagundes Loss, Lauro José Gregianin, André Tesainer Brunetto, Marialva Sinigaglia, Rafael Roesler, Mariane da Cunha Jaeger, Marcelo Land, Caroline Brunetto de Farias Cancers, 2025 Background: Neurotrophins (NTs) are pivotal growth factors in cellular development and survival. Their precise implications in Acute Lymphoblastic Leukemia (ALL) remain unclear. Methods: Pediatric ALL samples (2011–2021) were analyzed from a Southern Brazil cohort. Neurotrophin levels were quantified via ELISA, with survival analysis using Kaplan–Meier curves. Gene expression data were sourced from public genomic repositories and analyzed with R software version 4.0.5. Results: At diagnosis, pro-BDNF, BDNF, and NGF levels were significantly lower than in healthy controls. Reduced pro-BDNF correlated with unfavorable outcomes. NGF and sortilin were highly expressed in healthy samples, while BDNF and p75NTR were predominant in T-ALL and B-ALL, respectively. Conclusions: Neurotrophins show significant alterations in the tumor microenvironment of pediatric ALL. Further studies are needed to elucidate their precise role and prognostic potential.
Feature Selection in Cancer Classification: Utilizing Explainable Artificial Intelligence to Uncover Influential Genes in Machine Learning Models Matheus Dalmolin, Karolayne S. Azevedo, Luísa C. de Souza, Caroline B. de Farias, Martina Lichtenfels, Marcelo A. C. Fernandes AI Switzerland, 2025 This study investigates the use of machine learning (ML) models combined with explainable artificial intelligence (XAI) techniques to identify the most influential genes in the classification of five recurrent cancer types in women: breast cancer (BRCA), lung adenocarcinoma (LUAD), thyroid cancer (THCA), ovarian cancer (OV), and colon adenocarcinoma (COAD). Gene expression data from RNA-seq, extracted from The Cancer Genome Atlas (TCGA), were used to train ML models, including decision trees (DTs), random forest (RF), and XGBoost (XGB), which achieved accuracies of 98.69%, 99.82%, and 99.37%, respectively. However, the challenges in this analysis included the high dimensionality of the dataset and the lack of transparency in the ML models. To mitigate these challenges, the SHAP (Shapley Additive Explanations) method was applied to generate a list of features, aiming to understand which characteristics influenced the models’ decision-making processes and, consequently, the prediction results for the five tumor types. The SHAP analysis identified 119, 80, and 10 genes for the RF, XGB, and DT models, respectively, totaling 209 genes, resulting in 172 unique genes. The new list, representing 0.8% of the original input features, is coherent and fully explainable, increasing confidence in the applied models. Additionally, the results suggest that the SHAP method can be effectively used as a feature selector in gene expression data. This approach not only enhances model transparency but also maintains high classification performance, highlighting its potential in identifying biologically relevant features that may serve as biomarkers for cancer diagnostics and treatment planning.
Gastrin-releasing peptide receptor: a promising new biomarker to identify cervical precursor lesions and cancer Martina Lichtenfels, Rafaella Almeida Lima Nunes, Rossana Veronica Mendoza López, Camila Alves da Silva, Luiz Carlos Zeferino, Vanesca de Souza Lino, Adhemar Longatto-Filho, Louise De Brot, Silvia Helena Rabelo-Santos, Daniela Baumann Cornelio, Enrique Boccardo, Caroline Brunetto de Farias, Lara Termini Revista Brasileira De Ginecologia E Obstetricia, 2025 Objective: This study aimed to verify the relation between gastrin-releasing peptide receptor (GRPR), oncogenic Human Papillomavirus (HPV) and cervical lesions severity. Methods: GRPR mRNA levels were evaluated in cervical cancer-derived cell lines and in primary keratinocytes expressing HPV16 oncogenes by RT-PCR. GRPR protein expression was assessed by immunohistochemistry in organotypic cell cultures derived from keratinocytes transduced with HPV16 oncogenes and in 208 cervical samples, including 59 non-neoplastic tissue, 28 cervical intraepithelial neoplasia grade 3 (CIN3), 44 squamous cell carcinomas (SCC) and 77 adenocarcinomas (ADC). Generic primers (GP5+/GP6+) were used to identify HPV infection in tissue samples. Experiments involving cell lines were analyzed through non-parametric tests (Kruskal Wallis), and Fisher's Exact Test for human tissues samples. All statistical tests were considered significant at p <0.05. Immunohistochemical evaluation was conducted independently and blindly by two observers (AD- LO). Any discordant findings were resolved through discussion to reach a consensus score. Results: GRPR mRNA levels were not increased in cells expressing HPV16 or HPV18 oncogenes. However, at the protein level, GRPR was upregulated in organotypic cell cultures containing HPV oncogenes. Besides, it was identified an association between GRPR expression and cervical lesion severity (p < 0.0001). The detection rate of high-risk HPV DNA was directly correlated with cervical disease. Nonetheless, HPV infection was not directly associated with GRPR in cervical samples. Conclusion: GRPR expression is highly predictive of cervical lesion severity, irrespective of HPV infection and might contribute to improving patient's therapeutic management as well as being used a marker of disease progression.
Modulation of Stemness and Differentiation Regulators by Valproic Acid in Medulloblastoma Neurospheres Natália Hogetop Freire, Alice Laschuk Herlinger, Julia Vanini, Matheus Dalmolin, Marcelo A. C. Fernandes, Carolina Nör, Vijay Ramaswamy, Caroline Brunetto de Farias, André Tesainer Brunetto, Algemir Lunardi Brunetto, Lauro José Gregianin, Mariane da Cunha Jaeger, Michael D. Taylor, Rafael Roesler Cells, 2025 Changes in epigenetic processes such as histone acetylation are proposed as key events influencing cancer cell function and the initiation and progression of pediatric brain tumors. Valproic acid (VPA) is an antiepileptic drug that acts partially by inhibiting histone deacetylases (HDACs) and could be repurposed as an epigenetic anticancer therapy. Here, we show that VPA reduced medulloblastoma (MB) cell viability and led to cell cycle arrest. These effects were accompanied by enhanced H3K9 histone acetylation (H3K9ac) and decreased expression of the MYC oncogene. VPA impaired the expansion of MB neurospheres enriched in stemness markers and reduced MYC while increasing TP53 expression in these neurospheres. In addition, VPA induced morphological changes consistent with neuronal differentiation and the increased expression of differentiation marker genes TUBB3 and ENO2. The expression of stemness genes SOX2, NES, and PRTG was differentially affected by VPA in MB cells with different TP53 status. VPA increased H3K9 occupancy of the promoter region of TP53. Among the genes regulated by VPA, the stemness regulators MYC and NES showed an association with patient survival in specific MB subgroups. Our results indicate that VPA may exert antitumor effects in MB by influencing histone acetylation, which may result in the modulation of stemness, neuronal differentiation, and the expression of genes associated with patient prognosis in specific molecular subgroups. Importantly, the actions of VPA in MB cells and neurospheres include a reduction in the expression of MYC and an increase in TP53.
Optimizing breast cancer therapy: chemoressitance and machine learning for precision prediction Martina Lichtenfels, Matheus G. S. Dalmolin, Julia Caroline Marcolin, Heloisa Resende, Alessandra Borba Anton de Souza, Bianca Silva Marques, Vivian Fontana, Francine Hickmann Nyland, Mário Casales Schorr, Isabela Miranda, Luiza Kobe, Camila Alves da Silva, Marcelo AC Fernandes, Caroline Brunetto de Farias, Antônio Luiz Frasson, José Luiz Pedrini Personalized Medicine, 2025 BACKGROUND: Validate a novel in vitro resistance platform for breast cancer (BC) by assessing resistance profiles of treatment-naïve and residual tumors after neoadjuvant chemotherapy (NACT) and applying a machine learning algorithm to predict NACT response using clinical biomarkers. METHODS: Tumor cells from primary BC and residual disease (RD) were cultured on the chemoresistance platform with various chemotherapies. Resistance was categorized as low ( < 40%), medium (40-60%), or high ( > 60%) after 72 h based on cell viability. Clinicopathological data from BC samples were analyzed using the XGBoost algorithm and SHAP interpretation to identify NACT-resistant patients. RESULTS: = 27), which had higher drug resistance and worse outcomes. AI analysis of 1,012 patients achieved 82% accuracy in predicting pathological response and RD, with age, estrogen receptor status, tumor grade and size, axillary status, and HER2 status identified as key predictors. The algorithm predicted NACT resistance with 81.8% accuracy in 11 patient samples. CONCLUSION: The chemoresistance platform identified resistance patterns highlighting its utility in precision medicine. Additionally, the XGBoost algorithm accurately predicted NACT response, supporting the integration of AI with functional precision medicine for personalized BC treatment.
Stemness and Cell Cycle Regulators and Their Modulation by Retinoic Acid in Ewing Sarcoma Maria Eduarda Battistella, Natália Hogetop Freire, Bruno Toson, Matheus Dalmolin, Marcelo A. C. Fernandes, Isadora D. Tassinari, Mariane Jaeger, André T. Brunetto, Algemir L. Brunetto, Lauro Gregianin, Caroline Brunetto de Farias, Rafael Roesler Current Issues in Molecular Biology, 2024
A Case Study of a Rare Undifferentiated Spindle Cell Sarcoma of the Penis: Establishment and Characterization of Patient-Derived Models Ariane Cavalcante dos Santos Sousa, Bruno Leonardo Nascimento Correa Fernandes, Jeronimo Paulo Assis da Silva, Paulo Roberto Stevanato Filho, Luiza Bitencourt de Carvalho Terci Coimbra, Adriano de Oliveira Beserra, Ana Luiza Alvarenga, Giovanna Maida, Camila Tokumoto Guimaraes, Ingrid Martinez Nakamuta, Fabio Albuquerque Marchi, Camila Alves, Martina Lichtenfels, Caroline Brunetto de Farias, Bruna Elisa Catin Kupper, Felipe D’Almeida Costa, Celso Abdon Lopes de Mello, Dirce Maria Carraro, Giovana Tardin Torrezan, Ademar Lopes, Tiago Goss dos Santos Genes, 2024
Cancer Stem Cells and Chemoresistance in Ewing Sarcoma Rafael Pereira dos Santos, Rafael Roesler, Lauro Gregianin, André T. Brunetto, Mariane da Cunha Jaeger, Algemir Lunardi Brunetto, Caroline Brunetto de Farias Current Stem Cell Research and Therapy, 2023
Neurotrophin signaling in medulloblastoma Amanda Thomaz, Mariane Jaeger, Algemir L. Brunetto, André T. Brunetto, Lauro Gregianin, Caroline Brunetto de Farias, Vijay Ramaswamy, Carolina Nör, Michael D. Taylor, Rafael Roesler Cancers, 2020
Expression and pharmacological inhibition of TrkB and EGFR in glioblastoma Kelly V. Pinheiro, Amanda Thomaz, Bárbara Kunzler Souza, Victoria Anne Metcalfe, Natália Hogetop Freire, André Tesainer Brunetto, Caroline Brunetto de Farias, Mariane Jaeger, Victorio Bambini, Christopher G. S. Smith, Lisa Shaw, Rafael Roesler Molecular Biology Reports, 2020
HDAC and MAPK/ERK Inhibitors Cooperate To Reduce Viability and Stemness in Medulloblastoma Mariane da Cunha Jaeger, Eduarda Chiesa Ghisleni, Paula Schoproni Cardoso, Marialva Siniglaglia, Tiago Falcon, André T. Brunetto, Algemir L. Brunetto, Caroline Brunetto de Farias, Michael D. Taylor, Carolina Nör, Vijay Ramaswamy, Rafael Roesler Journal of Molecular Neuroscience, 2020
Trkb-targeted therapy for mucoepidermoid carcinoma Vivian P. Wagner, Manoela D. Martins, Esra Amoura, Virgilio G. Zanella, Rafael Roesler, Caroline B. de Farias, Colin D. Bingle, Pablo A. Vargas, Lynne Bingle Biomedicines, 2020
Antitumor activities and cellular changes induced by TrkB inhibition in medulloblastoma Amanda Thomaz, Kelly de Vargas Pinheiro, Bárbara Kunzler Souza, Lauro Gregianin, Algemir L. Brunetto, André T. Brunetto, Caroline Brunetto de Farias, Mariane da Cunha Jaeger, Vijay Ramaswamy, Carolina Nör, Michael D. Taylor, Rafael Roesler Frontiers in Pharmacology, 2019
Expression of neurotrophins and their receptors in primary osteosarcoma. Bruno Pereira Antunes, Ricardo Gehrke Becker, André Tesainer Brunetto, Bruno Silveira Pavei, Caroline Brunetto de-Farias, Luís Fernando da Rosa Rivero, Julie Francine Cerutti Santos, Bruna Medeiros de-Oliveira, Lauro José Gregianin, Rafael Roesler, Algemir Lunardi Brunetto, Fernando Pagnussato, Carlos Roberto Galia Revista do Colegio Brasileiro De Cirurgioes, 2019
Epidermal Growth Factor Receptor Regulation of Ewing Sarcoma Cell Function Nathália Kersting, Bárbara Kunzler Souza, Igor Araujo Vieira, Rafael Pereira dos Santos, Danielly Brufatto Olguins, Lauro José Gregianin, André Tesainer Brunetto, Algemir Lunardi Brunetto, Rafael Roesler, Caroline Brunetto de Farias, Gilberto Schwartsmann Oncology Switzerland, 2018
DNA damage response in patients with pediatric Acute Lymphoid Leukemia during induction therapy Júlia Plentz Portich, Rafael Pereira dos Santos, Nathalia Kersting, Karolina Brochado Jorge, Pietro Rebelo Casagrande, Gabriela dos Santos Costa, Jéssica Maria Gonçalves Dias Cionek, Danielly Brufatto Olguins, Marialva Sinigaglia, Franciele Faccio Busatto, Jenifer Saffi, Sharbel Weidner Maluf, Jiseh Fagundes Loss, Algemir Lunardi Brunetto, Rafael Roesler, Caroline Brunetto de Farias Leukemia Research, 2017
Targeting tyrosine receptor kinase B in gliomas Kelly V. Pinheiro, Camila Alves, Marienela Buendia, Mirela S. Gil, Amanda Thomaz, Gilberto Schwartsmann, Caroline Brunetto de Farias, Rafael Roesler, Robert L. Bowman, Qianghu Wang, Angel Carro, Roel G.W. Verhaak, Massimo Squatrito Neuro Oncology, 2017
Trk inhibition reduces cell proliferation and potentiates the effects of chemotherapeutic agents in Ewing sarcoma Tiago Elias Heinen, Rafael Pereira dos Santos, Amanda da Rocha, Michel Pinheiro dos Santos, Patrícia Luciana da Costa Lopez, Marco Aurélio Silva Filho, Bárbara Kunzler Souza, Luís Fernando da Rosa Rivero, Ricardo Gehrke Becker, Lauro José Gregianin, Algemir Lunardi Brunetto, André Tesainer Brunetto, Caroline Brunetto de Farias, Rafael Roesler Oncotarget, 2016
Genomic instability in human lymphocytes from male users of Crack Cocaine Thiago Freitas, Roberta Palazzo, Fabiana De Andrade, César Reichert, Flávio Pechansky, Félix Kessler, Caroline De Farias, Gisele De Andrade, Sandra Leistner-Segal, Sharbel Maluf International Journal of Environmental Research and Public Health, 2014
Mangifera indica L. extract (vimang) improves the aversive memory in spinocerebellar ataxia type 2 transgenic mice Journal of Pharmacy and Pharmacognosy Research, 2014
Ewing Sarcoma: Influence of TP53 Arg72Pro and MDM2 T309G SNPs Helena S. Thurow, Fernando P. Hartwig, Clarice S. Alho, Deborah S. B. S. Silva, Rafael Roesler, Ana Lucia Abujamra, Caroline Brunetto de Farias, Algemir Lunardi Brunetto, Bernardo L. Horta, Odir A. Dellagostin, Tiago Collares, Fabiana K. Seixas Molecular Biology Reports, 2013
BDNF/TrkB signaling as an anti-tumor target Rafael Roesler, Caroline Brunetto de Farias, Ana Lucia Abujamra, Algemir Lunardi Brunetto, Gilberto Schwartsmann Expert Review of Anticancer Therapy, 2011
Current and emerging molecular targets in glioma Rafael Roesler, André T Brunetto, Ana Lucia Abujamra, Caroline Brunetto de Farias, Algemir Lunardi Brunetto, Gilberto Schwartsmann Expert Review of Anticancer Therapy, 2010
Phosphodiesterase-4 inhibition and brain tumor growth Anna Laura Schmidt, Caroline Brunetto de Farias, Ana Lucia Abujamra, Algemir Lunardi Brunetto, Gilberto Schwartsmann, Rafael Roesler Clinical Cancer Research, 2009
