China 
Africa 
Explore chapters and articles related to this topic
Epigenetic and Metabolic Alterations in Cancer Cells: Mechanisms and Therapeutic Approaches
Published in Peter Grunwald, Pharmaceutical Biocatalysis, 2020
Paraganglioma exhibits recurrent mutations in the succinate dehydrogenase (SDH) genes. Sdhb knockout in mouse chromaffin cells triggered a CpG island methylator phenotype, with an increased 5-mC/5-hmC ratio, and enhanced histone methylation at H3K9me3, H3K27me2, and H3K27me3 (Letouze et al., 2013). The methylome abnormalities in Sdhb knockout cells induced the transcriptional silencing of genes involved in differentiation and metastasis suppression, leading to an invasive and migratory phenotype. In independent patient cohorts, mutant SDH is associated with a DNA methylator phenotype in paraganglioma and pheochromocytoma (Letouze et al., 2013). Moreover, paragangliomas with SDH or FH deficiency associated DNA methylator phenotype had a much worse prognosis compared with other subtypes, indicating that epigenetic dysregulation promotes tumor progression. Similarly, SDH mutations in GISTs are associated with genomic methylation an order of magnitude greater than that of SDH wildtype GISTs (Killian et al., 2013). Consistent with the inhibitory effect of succinate on DNA demethylation, SDH-mutant GISTs displayed a marked loss of TET activity. In vitro studies have shown that dominant negative expression of mutant FH- or SDH-, or metabolite supplementation (succinate and fumarate) recapitulates epigenetic phenotypes of FH- and SDH-mutant cancers, which is reversed upon a-ketoglutarate supplementation, further confirming the key role of TCA cycle metabolites in regulating the epigenome via modulating DNA/histone demethylation.
Poly(Alkyl Cyanoacrylate) Nanoparticles for Delivery of Anti-Cancer Drugs
Published in Mansoor M. Amiji, Nanotechnology for Cancer Therapy, 2006
R. S. R. Murthy, L. Harivardhan Reddy
Traditional preoperative embolization via a transarterial approach has proved beneficial, but it is often limited by complex vascular anatomy and unfavorable locations.195 Paragangliomas, or glomus tumors, are the neoplasms of the head and neck. They are remarkably vascular, so surgical resection can be complicated by rapid and dramatic blood loss.196 These tumors can develop in the middle ear (glomus tympanicum), the jugular foramen of the skull base (glomus jugulare), or the head and neck area (glomus caroticum, glomus vagale). Surgical removal of these tumors is also often associated with a significant intraoperative bleeding rate because of their vascular nature.197–199 Direct percutaneous injection of n-butyl cyanoacrylate resulted in the effective devascularization of craniofacial tumors200 and the embolization of oral tumors.201 However, the technique involved additional risks and was not widely adopted. In a study in human patients by Abud et al.,196 the presurgical devascularization was achieved by placing the diagnostic catheter in the common carotid artery to guide the puncture and perform the control angiography during and after the injection of the cyanoacrylate. The percutaneous devascularization of head and neck paragangliomas through the intralesional injection of cyanoacrylate resulted in effective devascularization. It could be a safe and effective technique for managing such clinical lesions.
Recent advances in nuclear and hybrid detection modalities for image-guided surgery
Published in Expert Review of Medical Devices, 2019
Matthias N. Van Oosterom, Daphne D.D. Rietbergen, Mick M. Welling, Henk G. Van Der Poel, Tobias Maurer, Fijs W.B. Van Leeuwen
18F-FDG PET/CT navigation of a laparoscope was demonstrated during lymph node salvage surgery for breast cancer and recurrent lymphoma [174]. SPECT/CT navigation has been applied more often, with navigation of a γ probe during open surgery SN procedures using (ICG-)99mTc-nanocolloid (e.g. penile cancer, melanoma, breast cancer, thyroid cancer and prostate cancer [101,175–177]), the resection of neuroendocrine tumors using 123I-MIBG (e.g. paraganglioma [101]) and parathyroid adenoma using 99mTc-MIBI [178]. All intraoperative studies so far were based on the same underlying technology: an intraoperative navigation system with near-infrared optical tracking and optical tracking fiducials attached to both the patient and the navigated instruments (see Figure 3(e)). This tracking setup allowed for a registration between the preoperative PET- or SPECT-based patient maps and the intraoperative instruments. During surgery, this allowed for more accurate positioning of the surgical instruments (see Figure 3(f–g)). However, these studies also indicated that navigation to soft tissues based on preoperative images can suffer from inaccuracies due to tissue deformations. By navigating a γ probe or fluorescence camera, the real-time feedback provided could partially correct for such inaccuracies [175,176,179–181].
Nuclear Medicine in Oncology
Published in Computer Methods in Biomechanics and Biomedical Engineering: Imaging & Visualization, 2018
Carla Oliveira, Rui Parafita, Ana Canudo, Joana Correia Castanheira, Durval C. Costa
If 131I is an agent in destroying thyroid tissue by the emission of beta minus particles (in addition to gamma radiation), labelling a guanethidine analogue – metaiodobenzylguanidine (MIBG) – with 131I will allow for the destruction of neoplastic tissue with the ability for catecholamine concentration. Therefore, the neuroendocrine tumours of the sympathetic-adrenal axis (pheochromocytoma, neuroblastoma, paraganglioma) stand out as the main therapeutic targets, with all other tumours that present an increased uptake of the radiopharmaceutical being potential candidates, such as medullary thyroid carcinoma and carcinoids.