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19 pages, 12690 KB  
Article
Curcumin Protects SDH2 Mutant from Oxidative Stress and Improves Mitochondrial Function: Application Potential for Complex II Deficiency
by Yi Liu, Na Wang and Heng Cai
Int. J. Mol. Sci. 2026, 27(12), 5253; https://doi.org/10.3390/ijms27125253 - 10 Jun 2026
Viewed by 401
Abstract
Complex II deficiency is a rare inherited mitochondrial disorder characterized by structural and functional deficiency of complex II, for which there is currently no definitive drug treatment. Curcumin is a polyphenolic compound with antioxidant, anti-inflammatory, anti-tumor, and anti-aging properties. By constructing a mutant [...] Read more.
Complex II deficiency is a rare inherited mitochondrial disorder characterized by structural and functional deficiency of complex II, for which there is currently no definitive drug treatment. Curcumin is a polyphenolic compound with antioxidant, anti-inflammatory, anti-tumor, and anti-aging properties. By constructing a mutant strain of the Saccharomyces cerevisiaeSDH2 gene, we can mimic the functional defects of Complex II caused by human SDHB mutations, and then explore the ameliorative effect of curcumin on Complex II functional defects. Cell viability was assessed using MTT and CFU. Antioxidant capacity was evaluated by measuring DCFH-DA and antioxidant enzyme activity, while the expression levels of respiratory chain-related genes were detected by qRT-PCR. Experimental results demonstrate that curcumin can restore cell growth and viability, scavenge ROS from cells as well as positively regulate mitochondrial function; however, the above results are regulated by the concentration of curcumin. In conclusion, these findings provide experimental support for curcumin as a preliminary intervention for Complex II deficiency and other mitochondrial diseases, further enriching the evidence for the potential application of curcumin in mitochondrial-related diseases. Full article
(This article belongs to the Section Molecular Biology)
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14 pages, 1525 KB  
Article
Whole-Blood Expression of Candidate Genes Linked with Pheochromocytoma in Post-Surgery Patients: A Pilot Study
by Timur Nurkhabinov, Kristina Maslova, Zarema Kokaeva, Anna Lugovskaya, Irena Ilovayskaya, Victor Popov and Lidia Nefedova
Biomedicines 2026, 14(2), 395; https://doi.org/10.3390/biomedicines14020395 - 9 Feb 2026
Viewed by 788
Abstract
Background: Pheochromocytomas (PCCs) and paragangliomas (PGLs), collectively known as PPGLs, are rare neuroendocrine tumors that produce catecholamines. The majority of PPGL cases are caused by germline and/or somatic mutations in over 20 different genes. A study of post-surgical PCC patients revealed a high [...] Read more.
Background: Pheochromocytomas (PCCs) and paragangliomas (PGLs), collectively known as PPGLs, are rare neuroendocrine tumors that produce catecholamines. The majority of PPGL cases are caused by germline and/or somatic mutations in over 20 different genes. A study of post-surgical PCC patients revealed a high risk of new tumor recurrence in both hereditary and apparently sporadic cases, suggesting that some germline mutations remain undetected. Since transcript levels can indicate gene dysfunction, our study focuses on the transcriptional profiling of PCC-associated genes in post-surgical patients. Methods: RT-PCR was performed on blood samples from patients and a control group. The t-SNE algorithm was applied to the transcriptional data. Sanger sequencing was used to identify mutations in the coding sequences of the VHL, SDHB, RET, and NF1 genes. Results: We obtained transcriptional profiles for 11 genes involved in the Krebs cycle and for 21 genes involved in the hypoxia, PI3K/AKT/mTOR, and RAS/RAF/ERK signaling pathways. We identified a minimal set of 16 genes with stable transcription levels that can be used to differentiate PCC patients from controls. Germline mutations in the VHL, SDHB, RET and NF1 genes, which correlated with an altered transcriptional profile, were detected in three patients. Conclusions: Our pilot data suggest that transcript levels of the genes involved in Krebs cycle, hypoxia, PI3K/AKT/mTOR, and RAS/RAF/ERK signaling pathways indicate their potential suitability as a candidate diagnostic marker. The results from this pilot study form the basis for a larger project to investigate gene transcription in an expanded cohort of patients who have undergone surgery for PCC. Full article
(This article belongs to the Special Issue Pathogenesis, Diagnosis and Treatment of Endocrine Cancers)
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16 pages, 276 KB  
Article
Clinical and Genetic Characteristics of Pheochromocytoma and Paraganglioma: A Single-Center Experience Including a Rare VHL Variant
by Merve Korkmaz Yilmaz, Ozlem Kandemir Alibakan, Aydeniz Aydin Gumus, Alper Gezdirici, Huseyin Karatay, Serkan Sari, Tugba Matlim Ozel, Mutlu Niyazoglu and Esra Hatipoglu
J. Clin. Med. 2026, 15(2), 712; https://doi.org/10.3390/jcm15020712 - 15 Jan 2026
Cited by 2 | Viewed by 1474
Abstract
Background/Objectives: Advances in the genetic understanding of pheochromocytoma–paraganglioma (PPGL) have considerably refined personalized approaches to diagnosis and management. This study aims to present our institutional experience on the diagnostic characteristics, clinical course, and genetic background of patients with PPGL, in the context of [...] Read more.
Background/Objectives: Advances in the genetic understanding of pheochromocytoma–paraganglioma (PPGL) have considerably refined personalized approaches to diagnosis and management. This study aims to present our institutional experience on the diagnostic characteristics, clinical course, and genetic background of patients with PPGL, in the context of the current literature. Methods: This retrospective analysis included 35 patients diagnosed with PPGL between years 2020 and 2024, all of whom underwent surgical resection and next-generation sequencing for germline mutations in major PPGL susceptibility genes. Clinical presentation, biochemical profile, pathological findings, and follow-up outcomes were compared between mutation-positive and mutation-negative cases. Results: Of the 35 patients with PPGL, germline mutations were identified in 6 patients (17%): 2 in Cluster 1A genes (SDHA, SDHB), 2 in Cluster 1B (VHL), and 2 in Cluster 2 (NF1). Consistent with existing literature, pathogenic germline variants—particularly SDHB and VHL—were identified in our cohort exclusively in patients younger than 30 years (ages 17, 20, and 25). Mutation-positive patients more frequently exhibited noradrenergic or non-secretory profiles (p = 0.01). Among the three non-secretory tumors in the cohort, two harbored genetic mutations (SDHA, NF1). Interestingly, both NF1-positive patients were normotensive—one (c.3496G > A) with a non-secretory tumor and the other (c.2329T > A) presenting at an unusually late age (63 years)—a strikingly atypical spectrum that underscores the phenotypic variability of NF1-associated PPGL. Bilateral disease was observed exclusively in VHL carriers (p = 0.03). Importantly, we identified a rare VHL c.369delG frameshift variant, not previously reported in association with PPGLs, in a patient with PPGL. No significant difference was observed between SDHB loss (p = 0.1) and proliferative indices (mitotic count, Ki-67) (p = 0.07, p = 0.6) between the two groups. During a median follow-up of 24 months (IQR: 18–36), one SDHB-positive patient had a recurrence, while no distant metastases were detected in the remaining mutation carriers. Conclusions: These findings support characteristic clinical patterns among mutation-positive PPGL and underscore the importance of systematic germline testing in all cases—irrespective of age, family history, or biochemical profile—to guide individualized management and enable cascade screening. The identification of a rare VHL c.369delG variant, previously unreported in association with PPGL, within a characteristic VHL-related clinical phenotype highlights the importance of this association. Similarly, atypical NF1 cases emphasize phenotypic variability and reinforce the importance of germline testing even in clinically silent presentations. Full article
(This article belongs to the Section Endocrinology & Metabolism)
18 pages, 326 KB  
Review
Update on Systemic Therapies for Metastatic/Unresectable Pheochromocytomas and Paragangliomas and Future Directions
by Imani Ghosh, Olivia Benson, Jorge H. Hernandez-Felix, Frank I. Lin, Karel Pacak and Jaydira del Rivero
Cancers 2025, 17(22), 3702; https://doi.org/10.3390/cancers17223702 - 19 Nov 2025
Cited by 4 | Viewed by 3661
Abstract
Metastatic or unresectable pheochromocytomas and paragangliomas (PPGLs) remain rare but clinically challenging neuroendocrine neoplasms with limited curative options. Traditionally managed with surgery, radionuclide therapy, or cytotoxic chemotherapy, systemic treatments have historically achieved disease stabilization, rather than durable remissions. In recent years, however, the [...] Read more.
Metastatic or unresectable pheochromocytomas and paragangliomas (PPGLs) remain rare but clinically challenging neuroendocrine neoplasms with limited curative options. Traditionally managed with surgery, radionuclide therapy, or cytotoxic chemotherapy, systemic treatments have historically achieved disease stabilization, rather than durable remissions. In recent years, however, the therapeutic landscape has evolved substantially. Radiopharmaceuticals such as 131I-MIBG and 177Lu-DOTATATE continue to play a pivotal role, achieving disease control in many patients. Cytotoxic regimens, particularly temozolomide, remain relevant, with some studies suggesting that SDHB-mutated PPGLs demonstrate a heightened sensitivity associated with MGMT promoter hypermethylation and reduced MGMT expression. Targeted agents are increasingly important: multi-kinase inhibitors such as sunitinib, anlotinib, and cabozantinib have shown meaningful activity. The landmark approval of belzutifan, a HIF-2α inhibitor, in 2025 represents the first oral targeted therapy for advanced/metastatic PPGL, which is particularly relevant for pseudohypoxic Cluster 1 tumors. Immunotherapy has yielded modest responses with checkpoint inhibitor monotherapy, but ongoing studies of dual checkpoint blockade and TKI–ICI combinations hold promise. Novel approaches, including PARP inhibition, metabolic targeting strategies, and cancer vaccines, are under investigation, especially for aggressive SDHB-related disease. Optimal sequencing of these therapies is emerging as a central challenge, with treatment strategies increasingly tailored to molecular genotype, tumor behavior, and functional imaging phenotype. This review summarizes current evidence and highlights ongoing clinical trials, underscoring a paradigm shift toward precision medicine and rational combination strategies. Collectively, these advances bring cautious optimism that metastatic PPGLs may soon become a more manageable chronic disease with improved survival and quality of life. Full article
(This article belongs to the Special Issue Updates in Neuroendocrine Neoplasms)
21 pages, 16371 KB  
Article
The Caenorhabditis elegans sdhb-1(R244H) Model Shows Characteristics of Human PPGL Tumor Cells
by Fanni Ősz, Mahmood Akbar, Balázs Zoltán Zsidó, Csaba Hetényi, Tamás I. Orbán, Ábel Fóthi, Gábor M. Kovács, Alexandra Pintye, Attila Boda, Aamir Nazir, Zsolt Farkas and Krisztina Takács-Vellai
Int. J. Mol. Sci. 2025, 26(20), 10185; https://doi.org/10.3390/ijms262010185 - 20 Oct 2025
Cited by 1 | Viewed by 1415
Abstract
Pheochromocytomas and paragangliomas (PPGL) are classified as rare cancers but can be highly metastatic, particularly in individuals with inherited succinate dehydrogenase B (SDHB) mutations. As current therapies and the availability of SDHB-deficient animal models are both limited, we have previously constructed a [...] Read more.
Pheochromocytomas and paragangliomas (PPGL) are classified as rare cancers but can be highly metastatic, particularly in individuals with inherited succinate dehydrogenase B (SDHB) mutations. As current therapies and the availability of SDHB-deficient animal models are both limited, we have previously constructed a nematode PPGL model, a transgenic worm carrying the R244H missense mutation equivalent to human R230H in the sdhb-1 gene. In this study, we show that R244H mutants display characteristics of PPGL tumors, such as pseudohypoxia activation and the accumulation of reactive oxygen species. The latter can be the result of compromised antioxidant machinery, as R244H mutants have reduced levels of cytosolic and mitochondrial superoxide dismutase enzymes. In addition, the expression of mitophagy markers pink-1 (PTEN-induced putative kinase) and pdr-1 (E3 ubiquitin-protein ligase parkin) were downregulated in R244H mutants, suggesting impaired mitophagy and reflecting the crucial role of mitochondrial health in PPGL pathology. Treatments by the SDH inhibitor fluopyram revealed that the SDH complex carrying the R244H mutation in subunit B displayed residual SDH activity, which was also confirmed by our structural analyses. We also observed a link between dopaminergic neuronal health and SDHB-1. Full article
(This article belongs to the Special Issue C. elegans as a Disease Model: Molecular Perspectives: 2nd Edition)
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15 pages, 6556 KB  
Article
Adaptive Resistance of Staphylococcus aureus to Cefquinome Sulfate in an In Vitro Pharmacokinetic Model with Transcriptomic Insights
by Yue Hu, Hao Zhu, Xingbo Zhang, Yuhui Wu, Jingtao Li, Nan Li, Zhanbo Cai and Yuhui Yang
Microorganisms 2025, 13(2), 329; https://doi.org/10.3390/microorganisms13020329 - 2 Feb 2025
Cited by 1 | Viewed by 1726
Abstract
Cefquinome sulfate has a strong killing effect against Staphylococcus aureus (S. aureus), but bacterial resistance has become increasingly widespread. Experiments were conducted to investigate the pattern of adaptive resistance of S. aureus to cefquinome sulfate under different dosage regimens by using [...] Read more.
Cefquinome sulfate has a strong killing effect against Staphylococcus aureus (S. aureus), but bacterial resistance has become increasingly widespread. Experiments were conducted to investigate the pattern of adaptive resistance of S. aureus to cefquinome sulfate under different dosage regimens by using pharmacokinetic-pharmacodynamics (PK-PD) modeling, and the adaptive-resistant bacteria in different states were screened and subjected to transcriptomic sequencing. The results showed that the minimum inhibitory concentration of Staphylococcus aureus under the action of cefquinome sulfate was 0.5 μg/mL, the anti-mutation concentration was 1.6 μg/mL, and the mutation selection window range was 0.5~1.6 μg/mL. In the in vitro pharmacokinetic model to simulate different dosing regimens in the animal body, there are certain rules for the emergence of adaptive drug-resistant bacteria: the intensity of bacterial resistance gradually increased with culture time, and the order of emergence was tolerant bacteria (TO) followed by persistent bacteria (PE) and finally resistant bacteria (RE). The sequence reflected the evolution of adaptive drug resistance. Transcriptome Gene Ontology (GO) analysis revealed that differentially expressed genes were involved in cellular respiration, energy derivation by oxidation of organic compounds, and oxidation–reduction processes. The differentially expressed genes identified functioned in the synthesis of cell membranes, cytoplasm, and intracellular parts. A Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis found that 65 genes were differentially expressed after cefquinome sulfate treatment, of which 35 genes were significantly upregulated and 30 genes were significantly downregulated. Five genes, sdhB, sdhA, pdhA, lpdA, and sucC, may be involved in network regulation. This study revealed the cross-regulation of multiple metabolic pathway networks and the targets of network regulation of S. aureus to produce adaptive drug resistance. The results will provide guidance for clinical drug use in animals infected with S. aureus. Full article
(This article belongs to the Section Antimicrobial Agents and Resistance)
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19 pages, 1159 KB  
Review
Pheochromocytoma–Paraganglioma Syndrome: A Multiform Disease with Different Genotype and Phenotype Features
by Mara Giacché, Maria Chiara Tacchetti, Claudia Agabiti-Rosei, Francesco Torlone, Francesco Bandera, Claudia Izzi and Enrico Agabiti-Rosei
Biomedicines 2024, 12(10), 2385; https://doi.org/10.3390/biomedicines12102385 - 18 Oct 2024
Cited by 9 | Viewed by 6276
Abstract
Pheochromocytoma and paraganglioma (PPGL) are rare tumors derived from the adrenal medulla and extra-adrenal chromaffin cells. Diagnosis is often challenging due to the great variability in clinical presentation; the complexity of management due to the dangerous effects of catecholamine excess and the potentially [...] Read more.
Pheochromocytoma and paraganglioma (PPGL) are rare tumors derived from the adrenal medulla and extra-adrenal chromaffin cells. Diagnosis is often challenging due to the great variability in clinical presentation; the complexity of management due to the dangerous effects of catecholamine excess and the potentially malignant behavior require in-depth knowledge of the pathology and multidisciplinary management. Nowadays, diagnostic ability has certainly improved and guidelines and consensus documents for treatment and follow-up are available. A major impulse to the development of this knowledge has come from the new findings on the genetic and molecular characteristics of PPGLs. Germline mutation in susceptibility genes is detected in 40% of subjects, with a mutation frequency of 10–12% also in patients with sporadic presentation and genetic testing should be incorporated within clinical care. PPGL susceptibility genes include “old genes” associated with Neurofibromatosis type 1 (NF1 gene), Von Hippel Lindau syndrome (VHL gene) and Multiple Endocrine Neoplasia type 2 syndrome (RET gene), the family of SDHx genes (SDHA, SDHB, SDHC, SDHD, SDHAF2), and genes less frequently involved such as TMEM, MAX, and FH. Each gene has a different risk of relapse, malignancy, and other organ involvement; for mutation carriers, affected or asymptomatic, it is possible to define a tailored long-life surveillance program according to the gene involved. In addition, molecular characterization of the tumor has allowed the identification of somatic mutations in other driver genes, bringing to 70% the PPGLs for which we know the mechanisms of tumorigenesis. This has expanded the catalog of tumor driver genes, which are identifiable in up to 70% of patients Integrated genomic and transcriptomic data over the last 10 years have revealed three distinct major molecular signatures, triggered by pathogenic variants in susceptibility genes and characterized by the activation of a specific oncogenic signaling: the pseudo hypoxic, the kinase, and the Wnt signaling pathways. These molecular clusters show a different biochemical phenotype and clinical behavior; they may also represent the prerequisite for implementing customized therapy and follow-up. Full article
(This article belongs to the Special Issue Adrenal Diseases: An Update)
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19 pages, 4197 KB  
Article
Polyamine Pathway Inhibitor DENSPM Suppresses Lipid Metabolism in Pheochromocytoma Cell Line
by Hans K. Ghayee, Kaylie A. Costa, Yiling Xu, Heather M. Hatch, Mateo Rodriguez, Shelby C. Straight, Marian Bustamante, Fahong Yu, Fatima Smagulova, John A. Bowden and Sergei G. Tevosian
Int. J. Mol. Sci. 2024, 25(18), 10029; https://doi.org/10.3390/ijms251810029 - 18 Sep 2024
Cited by 1 | Viewed by 3291
Abstract
Pheochromocytomas (PCCs) are tumors arising from chromaffin cells in the adrenal medulla, and paragangliomas (PGLs) are tumors derived from extra-adrenal sympathetic or parasympathetic paraganglia; these tumors are collectively referred to as PPGL cancer. Treatment for PPGL primarily involves surgical removal of the tumor, [...] Read more.
Pheochromocytomas (PCCs) are tumors arising from chromaffin cells in the adrenal medulla, and paragangliomas (PGLs) are tumors derived from extra-adrenal sympathetic or parasympathetic paraganglia; these tumors are collectively referred to as PPGL cancer. Treatment for PPGL primarily involves surgical removal of the tumor, and only limited options are available for treatment of the disease once it becomes metastatic. Human carriers of the heterozygous mutations in the succinate dehydrogenase subunit B (SDHB) gene are susceptible to the development of PPGL. A physiologically relevant PCC patient-derived cell line hPheo1 was developed, and SDHB_KD cells carrying a stable short hairpin knockdown of SDHB were derived from it. An untargeted metabolomic approach uncovered an overactive polyamine pathway in the SDHB_KD cells that was subsequently fully validated in a large set of human SDHB-mutant PPGL tumor samples. We previously reported that treatment with the polyamine metabolism inhibitor N1,N11-diethylnorspermine (DENSPM) drastically inhibited growth of these PCC-derived cells in culture as well as in xenograft mouse models. Here we explored the mechanisms underlying DENSPM action in hPheo1 and SDHB_KD cells. Specifically, by performing an RNAseq analysis, we have identified gene expression changes associated with DENSPM treatment that broadly interfere with all aspects of lipid metabolism, including fatty acid (FA) synthesis, desaturation, and import/uptake. Furthermore, by performing an untargeted lipidomic liquid chromatography–mass spectrometry (LC/MS)-based analysis we uncovered specific groups of lipids that are dramatically reduced as a result of DENSPM treatment. Specifically, the bulk of plasmanyl ether lipid species that have been recently reported as the major determinants of cancer cell fate are notably decreased. In summary, this work suggests an intersection between active polyamine and lipid pathways in PCC cells. Full article
(This article belongs to the Special Issue Molecular Aspects of Adrenal Diseases and Carcinoma)
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14 pages, 878 KB  
Review
Genetic and Molecular Biomarkers in Aggressive Pheochromocytomas and Paragangliomas
by Francesca Torresan, Clelia Iacobone, Francesco Giorgino and Maurizio Iacobone
Int. J. Mol. Sci. 2024, 25(13), 7142; https://doi.org/10.3390/ijms25137142 - 28 Jun 2024
Cited by 9 | Viewed by 3952
Abstract
Pheochromocytomas and paragangliomas (PPGLs) are rare neoplasms producing catecholamines that occur as hereditary syndromes in 25–40% of cases. To date, PPGLs are no longer classified as benign and malignant tumors since any lesion could theoretically metastasize, even if it occurs only in a [...] Read more.
Pheochromocytomas and paragangliomas (PPGLs) are rare neoplasms producing catecholamines that occur as hereditary syndromes in 25–40% of cases. To date, PPGLs are no longer classified as benign and malignant tumors since any lesion could theoretically metastasize, even if it occurs only in a minority of cases (approximately 10–30%). Over the last decades, several attempts were made to develop a scoring system able to predict the risk of aggressive behavior at diagnosis, including the risk of metastases and disease recurrence; unfortunately, none of the available scores is able to accurately predict the risk of aggressive behavior, even including clinical, biochemical, and histopathological features. Thus, life-long follow-up is required in PPGL patients. Some recent studies focusing on genetic and molecular markers (involved in hypoxia regulation, gene transcription, cellular growth, differentiation, signaling pathways, and apoptosis) seem to indicate they are promising prognostic factors, even though their clinical significance needs to be further evaluated. The most involved pathways in PPGLs with aggressive behavior are represented by Krebs cycle alterations caused by succinate dehydrogenase subunits (SDHx), especially when caused by SDHB mutations, and by fumarate hydratase mutations that lead to the activation of hypoxia pathways and DNA hypermethylation, suggesting a common pathway in tumorigenesis. Conversely, PPGLs showing mutations in the kinase cascade (cluster 2) tend to display less aggressive behavior. Finally, establishing pathways of tumorigenesis is also fundamental to developing new drugs targeted to specific pathways and improving the survival of patients with metastatic disease. Unfortunately, the rarity of these tumors and the scarce number of cases enrolled in the available studies represents an obstacle to validating the role of molecular markers as reliable predictors of aggressiveness. Full article
(This article belongs to the Special Issue Molecular Aspects of Adrenal Diseases and Carcinoma)
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16 pages, 1764 KB  
Article
Utility of Clinical Next Generation Sequencing Tests in KIT/PDGFRA/SDH Wild-Type Gastrointestinal Stromal Tumors
by Ryan A. Denu, Cissimol P. Joseph, Elizabeth S. Urquiola, Precious S. Byrd, Richard K. Yang, Ravin Ratan, Maria Alejandra Zarzour, Anthony P. Conley, Dejka M. Araujo, Vinod Ravi, Elise F. Nassif Haddad, Michael S. Nakazawa, Shreyaskumar Patel, Wei-Lien Wang, Alexander J. Lazar and Neeta Somaiah
Cancers 2024, 16(9), 1707; https://doi.org/10.3390/cancers16091707 - 27 Apr 2024
Cited by 11 | Viewed by 5658
Abstract
Objective: The vast majority of gastrointestinal stromal tumors (GISTs) are driven by activating mutations in KIT, PDGFRA, or components of the succinate dehydrogenase (SDH) complex (SDHA, SDHB, SDHC, and SDHD genes). A small fraction of GISTs lack [...] Read more.
Objective: The vast majority of gastrointestinal stromal tumors (GISTs) are driven by activating mutations in KIT, PDGFRA, or components of the succinate dehydrogenase (SDH) complex (SDHA, SDHB, SDHC, and SDHD genes). A small fraction of GISTs lack alterations in KIT, PDGFRA, and SDH. We aimed to further characterize the clinical and genomic characteristics of these so-called “triple-negative” GISTs. Methods: We extracted clinical and genomic data from patients seen at MD Anderson Cancer Center with a diagnosis of GIST and available clinical next generation sequencing data to identify “triple-negative” patients. Results: Of the 20 patients identified, 11 (55.0%) had gastric, 8 (40.0%) had small intestinal, and 1 (5.0%) had rectal primary sites. In total, 18 patients (90.0%) eventually developed recurrent or metastatic disease, and 8 of these presented with de novo metastatic disease. For the 13 patients with evaluable response to imatinib (e.g., neoadjuvant treatment or for recurrent/metastatic disease), the median PFS with imatinib was 4.4 months (range 0.5–191.8 months). Outcomes varied widely, as some patients rapidly developed progressive disease while others had more indolent disease. Regarding potential genomic drivers, four patients were found to have alterations in the RAS/RAF/MAPK pathway: two with a BRAF V600E mutation and two with NF1 loss-of-function (LOF) mutations (one deletion and one splice site mutation). In addition, we identified two with TP53 LOF mutations, one with NTRK3 fusion (ETV6-NTRK3), one with PTEN deletion, one with FGFR1 gain-of-function (GOF) mutation (K654E), one with CHEK2 LOF mutation (T367fs*), one with Aurora kinase A fusion (AURKA-CSTF1), and one with FANCA deletion. Patients had better responses with molecularly targeted therapies than with imatinib. Conclusions: Triple-negative GISTs comprise a diverse cohort with different driver mutations. Compared to KIT/PDGFRA-mutant GIST, limited benefit was observed with imatinib in triple-negative GIST. In depth molecular profiling can be helpful in identifying driver mutations and guiding therapy. Full article
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15 pages, 239 KB  
Article
Head and Neck Paragangliomas: Overview of Institutional Experience
by Swar N. Vimawala, Alex Z. Graboyes, Bonita Bennett, Maria Bonanni, Aleena Abbasi, Tanaya Oliphant, Michelle Alonso-Basanta, Christopher Rassekh, Debbie Cohen, Jason A. Brant and Yonghong Huan
Cancers 2024, 16(8), 1523; https://doi.org/10.3390/cancers16081523 - 16 Apr 2024
Cited by 10 | Viewed by 3110
Abstract
Head and neck paragangliomas (HNPGLs) are rare and have high rates of genetic mutations. We conducted a retrospective review of 187 patients with 296 PGLs diagnosed between 1974 and 2023. The mean age of diagnosis was 48.8 years (range 10 to 82) with [...] Read more.
Head and neck paragangliomas (HNPGLs) are rare and have high rates of genetic mutations. We conducted a retrospective review of 187 patients with 296 PGLs diagnosed between 1974 and 2023. The mean age of diagnosis was 48.8 years (range 10 to 82) with 69.0% female and 26.5% patients with multiple PGLs. Among 119 patients undergoing genetic testing, 70 (58.8%) patients had mutations, with SDHB (30) and SDHD (26) being the most common. The rates of metastasis and recurrence were higher among patients with SDHB mutations or SDHD mutations associated with multiple PGLs. Metabolic evaluation showed elevated plasma dopamine levels were the most common derangements in HNPGL. MRI and CT were the most common anatomic imaging modalities and DOTATATE was the most common functional scan used in this cohort. Most patients (81.5%) received surgery as the primary definitive treatment, while 22.5% patients received radiation treatment, mostly as an adjuvant therapy or for surgically challenging or inoperable cases. Systemic treatment was rarely used in our cohort. Our single-center experience highlights the need for referral for genetic testing and metabolic evaluation and for a team-based approach to improve the clinical outcomes of patients with HNPGLs. Full article
13 pages, 8120 KB  
Case Report
ETV6::NTRK3 Fusion-Positive Wild-Type Gastrointestinal Stromal Tumor (GIST) with Abundant Lymphoid Infiltration (TILs and Tertiary Lymphoid Structures): A Report on a New Case with Therapeutic Implications and a Literature Review
by Isidro Machado, Reyes Claramunt-Alonso, Javier Lavernia, Ignacio Romero, María Barrios, María José Safont, Nuria Santonja, Lara Navarro, José Antonio López-Guerrero and Antonio Llombart-Bosch
Int. J. Mol. Sci. 2024, 25(7), 3707; https://doi.org/10.3390/ijms25073707 - 26 Mar 2024
Cited by 12 | Viewed by 3710
Abstract
Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract, with proto-oncogene, receptor tyrosine kinase (c-kit), or PDGFRα mutations detected in around 85% of cases. GISTs without c-kit or platelet-derived growth factor receptor alpha (PDGFRα) [...] Read more.
Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract, with proto-oncogene, receptor tyrosine kinase (c-kit), or PDGFRα mutations detected in around 85% of cases. GISTs without c-kit or platelet-derived growth factor receptor alpha (PDGFRα) mutations are considered wild-type (WT), and their diverse molecular alterations and biological behaviors remain uncertain. They are usually not sensitive to tyrosine kinase inhibitors (TKIs). Recently, some molecular alterations, including neurotrophic tyrosine receptor kinase (NTRK) fusions, have been reported in very few cases of WT GISTs. This novel finding opens the window for the use of tropomyosin receptor kinase (TRK) inhibitor therapy in these subtypes of GIST. Herein, we report a new case of NTRK-fused WT high-risk GIST in a female patient with a large pelvic mass (large dimension of 20 cm). The tumor was removed, and the histopathology displayed spindle-predominant morphology with focal epithelioid areas, myxoid stromal tissue, and notable lymphoid infiltration with tertiary lymphoid structures. Ten mitoses were quantified in 50 high-power fields without nuclear pleomorphism. DOG1 showed strong and diffuse positivity, and CD117 showed moderate positivity. Succinate dehydrogenase subunit B (SDHB) was retained, Pan-TRK was focal positive (nuclear pattern), and the proliferation index Ki-67 was 7%. Next-generation sequencing (NGS) detected an ETV6::NTRK3 fusion, and this finding was confirmed by fluorescence in situ hybridization (FISH), which showed NTRK3 rearrangement. In addition, an RB1 mutation was found by NGS. The follow-up CT scan revealed peritoneal nodules suggestive of peritoneal dissemination, and Entrectinib (a TRK inhibitor) was administered. After 3 months of follow-up, a new CT scan showed a complete response. Based on our results and the cases from the literature, GISTs with NTRK fusions are very uncommon so far; hence, further screening studies, including more WT GIST cases, may increase the possibility of finding additional cases. The present case may offer new insights into the potential introduction of TRK inhibitors as treatments for GISTs with NTRK fusions. Additionally, the presence of abundant lymphoid infiltration in the present case may prompt further research into immunotherapy as a possible additional therapeutic option. Full article
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22 pages, 6945 KB  
Article
Resistance to Site-Specific Succinate Dehydrogenase Inhibitor Fungicides Is Pervasive in Populations of Black and Yellow Sigatoka Pathogens in Banana Plantations from Southeastern Brazil
by Tatiane C. Silva, Silvino I. Moreira, Daniel M. de Souza, Felix S. Christiano, Maria C. G. Gasparoto, Bart A. Fraaije, Gustavo H. Goldman and Paulo C. Ceresini
Agronomy 2024, 14(4), 666; https://doi.org/10.3390/agronomy14040666 - 25 Mar 2024
Cited by 9 | Viewed by 4169
Abstract
The Sigatoka disease complex (SDC), caused by Mycosphaerella fijiensis (Mf) and M. musicola (Mm), comprises the most destructive fungal leaf streak and spot diseases of commercial banana crops worldwide. In Brazil, the site-specific succinate dehydrogenase inhibitor (SDHI) fungicides labeled [...] Read more.
The Sigatoka disease complex (SDC), caused by Mycosphaerella fijiensis (Mf) and M. musicola (Mm), comprises the most destructive fungal leaf streak and spot diseases of commercial banana crops worldwide. In Brazil, the site-specific succinate dehydrogenase inhibitor (SDHI) fungicides labeled for SDC management since 2014 present a high risk for the emergence of resistance if deployed intensively and solo. Our study determined the levels of sensitivity to boscalid and fluxapyroxad in four populations of the SDC pathogens sampled in 2020 from three distinct geographical regions under contrasting fungicide programs. Resistance, defined as EC50 values exceeding 20 µg mL−1, was prevalent at 59.7% for fluxapyroxad and 94.0% for boscalid. Only 1.5% of isolates exhibited sensitivity to both fungicides. We also assessed the changes in the corresponding fungicide target protein-encoding genes (SdhB, C, and D). None of the target site alterations detected were associated with reduced sensitivity. A second SdhC paralog was also analyzed, but target alterations were not found. However, MDR (multidrug resistance) was detected in a selection of isolates. Further monitoring for Sdh target mutations will be important, but an important role for other resistance mechanisms such as the presence of additional Sdh paralogs and MDR cannot be ruled out. These results highlight the importance of implementing sound anti-resistance management strategies when SDHI fungicides are deployed for the management of SDC. Full article
(This article belongs to the Section Pest and Disease Management)
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9 pages, 1586 KB  
Article
Expansion of Electron Transport Chain Mutants That Cause Anesthetic-Induced Toxicity in Drosophila melanogaster
by Luke A. Borchardt, Zachariah P. G. Olufs, Philip G. Morgan, David A. Wassarman and Misha Perouansky
Oxygen 2024, 4(1), 108-116; https://doi.org/10.3390/oxygen4010006 - 2 Mar 2024
Cited by 1 | Viewed by 1973
Abstract
The mitochondrial electron transport chain (mETC) contains molecular targets of volatile general anesthetics (VGAs), which places individuals with mETC mutations at risk for anesthetic complications, as exemplified by patients with Leigh syndrome (LS). The Drosophila melanogaster homozygous mutant for ND-23, which encodes [...] Read more.
The mitochondrial electron transport chain (mETC) contains molecular targets of volatile general anesthetics (VGAs), which places individuals with mETC mutations at risk for anesthetic complications, as exemplified by patients with Leigh syndrome (LS). The Drosophila melanogaster homozygous mutant for ND-23, which encodes a subunit of mETC Complex I, replicates numerous characteristics of LS, including neurodegeneration, shortened lifespan, behavioral anesthetic hypersensitivity, and toxicity. The anesthetic phenotype of toxicity (lethality) is also observed in flies homozygous for mutations in other Complex I subunits. By contrast, mutations conferring sensitivity have not yet been identified for subunits of Complexes II–V. Furthermore, anesthetic phenotypes are thought to be recessive; that is, risk is not conferred by heterozygous mutations. However, at older ages, exposure of heterozygous mutant ND-23 flies to the VGA isoflurane in 75% oxygen (hyperoxia) results in toxicity. It is also unknown whether combinations of heterozygous mutations in different subunits of the mETC can result in anesthetic toxicity. Here, we show that, following exposure to isoflurane in hyperoxia, flies carrying heterozygous mutations in two Complex I subunits, ND-23 and ND-SGDH (NADH dehydrogenase (ubiquinone) SGDH subunit), had a level of anesthetic toxicity that exceeded the added toxicities of the individual heterozygous mutations. In addition, we show that flies heterozygous for two different alleles of the Complex II gene SdhB were susceptible to isoflurane/hyperoxia-induced anesthetic toxicity. Finally, a mutation in the SdhC subunit of Complex II of Caenorhabditis elegans resulted in isoflurane-induced mortality, supporting the role of Complex II in anesthetic toxicity. These data expand the landscape of mutations in the mETC that increase sensitivity to anesthetic toxicity. Full article
(This article belongs to the Special Issue Mitochondrial Oxidative Stress in Health and Disease)
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13 pages, 1307 KB  
Review
Hypoxic Signaling Pathways in Carotid Body Tumors
by Kangxi Cao, Wanzhong Yuan, Chaofan Hou, Zhongzheng Wang, Jiazhi Yu and Tao Wang
Cancers 2024, 16(3), 584; https://doi.org/10.3390/cancers16030584 - 30 Jan 2024
Cited by 12 | Viewed by 4845
Abstract
Carotid body tumors (CBTs) are rare tumors with a 1–2 incidence per 100,000 individuals. CBTs may initially present without apparent symptoms, and symptoms begin to arise since tumors grow bigger to compress surrounding tissue, such as recurrent laryngeal nerve and esophagus. Also, the [...] Read more.
Carotid body tumors (CBTs) are rare tumors with a 1–2 incidence per 100,000 individuals. CBTs may initially present without apparent symptoms, and symptoms begin to arise since tumors grow bigger to compress surrounding tissue, such as recurrent laryngeal nerve and esophagus. Also, the etiology of CBTs remains unclear since it is more likely to occur in those who live in high-altitude areas or suffer from chronic hypoxic diseases such as COPD. SDH mutations and familial inheritance have been reported to be related to CBTs. SDH complexes play crucial roles in aerobic respiration, and SDH mutations in CBTs have been reported to be associated with hypoxia. Hypoxic signaling pathways, specifically hypoxic markers, have attracted more research attention in tumor exploration. However, the existing literature on these signaling and markers lacks a systematic review. Also, therapeutic approaches in CBTs based on hypoxic signaling are rarely used in clinics. In this review, we concluded the role of hypoxic signaling and markers and their potential implications in the initiation and progression of CBTs. Our findings underscore the involvement of the SDH family, the HIF family, VEGFs, and inflammatory cytokines (ICs) in tumorigenesis and treatment. Of particular interest is the role played by SDHx, which has recently been linked to oxygen sensing through mutations leading to hereditary CBTs. Among the SDH family, SDHB and SDHD exhibit remarkable characteristics associated with metastasis and multiple tumors. Besides SDH mutations in CBTs, the HIF family also plays crucial roles in CBTs via hypoxic signaling pathways. The HIF family regulates angiogenesis during mammalian development and tumor growth by gene expression in CBTs. HIF1α could induce the transcription of pyruvate dehydrogenase kinase 1 (PDK1) to inhibit pyruvate dehydrogenase kinase (PDH) by inhibiting the TCA cycle. Then, carotid body cells begin to hyperplasia and hypertrophy. At the same time, EPAS1 mutation, an activating mutation, could decrease the degradation of HIF2α and result in Pacak–Zhuang syndrome, which could result in paraganglioma. HIFs can also activate VEGF expression, and VEGFs act on Flk-1 to control the hyperplasia of type I cells and promote neovascularization. ICs also play a pivotal signaling role within the CB, as their expression is induced under hypoxic conditions to stimulate CB hyperplasia, ultimately leading to CBTs detecting hypoxic areas in tumors, and improving the hypoxic condition could enhance photon radiotherapy efficacy. Moreover, this review offers valuable insights for future research directions on understanding the relationship between hypoxic signaling pathways and CBTs. Full article
(This article belongs to the Section Systematic Review or Meta-Analysis in Cancer Research)
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