Composite pheochromocytoma/paraganglioma is a rare tumor with elements of pheochromocytoma/paraganglioma and neurogenic tumor. Most were located in the adrenal glands, and extra-adrenal composite pheochromocytoma is extremely rare. Only 4 cases in the retroperitoneum have been described in the online database PUBMED. Here, we report a case of retroperitoneal extra-adrenal composite pheochromocytoma and review the related literature.Virtual slidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1700539911908679
Background
Drug resistance is common in cancer chemotherapy. This study investigates the role of Glycerol kinase 5 (GK5) in mediating gefitinib resistance in NSCLC.
Methods
The exosomal mRNA of GK5 was detected using a tethered cationic lipoplex nanoparticle (TCLN) biochip. Real-time PCR and Western blot were used to examine the expression of GK5 mRNA and protein in gefitinib-sensitive and -resistant human lung adenocarcinoma cells. The cell counting kit-8, EdU assay, flow cytometry, and JC-1 dye were used to measure cell proliferation, cell cycle, and the mitochondrial membrane potential.
Results
We found that the exosomal mRNA of GK5 in the plasma of patients with gefitinib-resistant adenocarcinoma was significantly higher compared with that of gefitinib-sensitive patients. The mRNA and protein levels of GK5 were significantly upregulated in gefitinib-resistant human lung adenocarcinoma PC9R and H1975 cells compared with gefitinib-sensitive PC9 cells. Silencing GK5 in PC9R cells induced mitochondrial damage, caspase activation, cell cycle arrest, and apoptosis via SREBP1/SCD1 signaling pathway.
Conclusions
We demonstrated that GK5 confers gefitinib resistance in lung cancer by inhibiting apoptosis and cell cycle arrest. GK5 could be a novel therapeutic target for treatment of NSCLC with resistance to EGFR tyrosine kinase inhibitors.
The larger aggregate dimension of tumor, the higher metastatic rate of axillary lymph node and the high Ki-67 proliferative index seen in most cases, suggest that MMBC is biologically more aggressive than unifocal breast cancer. In addition, every focus should be tested owing to the existence of different expressions of immunostaining between foci.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.