Hereditary leiomyomatosis and renal cell carcinoma syndrome-associated renal cell carcinomas (RCC) are difficult to diagnose prospectively. We used immunohistochemistry (IHC) to identify fumarate hydratase (FH)-deficient tumors (defined as FH negative, 2-succinocysteine [2SC] positive) in cases diagnosed as "unclassified RCC, high grade or with papillary pattern," or "papillary RCC type 2," from multiple institutions. A total of 124 tumors (from 118 patients) were evaluated by IHC for FH and 2SC. An FH deficiency was found in 24/124 (19%) cases. An indeterminate result (only 1 marker abnormal) was found in 27/124 (22%) cases. In a tissue microarray of 776 RCCs of different types, only 2 (0.5%) tumors, initially considered papillary type 2, were FH deficient. FH mutations were found in 19/21 FH-deficient tumors (with confirmed germline mutations in 9 of 9 tumors in which germline status could be assessed) and in 1/26 FH-indeterminate tumors identified by IHC. No FH mutations were found in 2/21 FH-deficient RCCs, 25/26 FH-indeterminate RCCs, and 10/10 RCCs demonstrating FH expression by IHC. Patients with FH-deficient RCC had a median age of 44 years (range, 21 to 65 y). Average tumor size was 8.2 cm (range, 0.9 to 18 cm). FH-deficient RCCs were characterized by at least focal macronucleoli and demonstrated 2 or more growth patterns in 93% cases. Papillary was the most common (74%) and dominant (59%) pattern, whereas other common patterns included: solid (44%), tubulocystic (41%), cribriform (41%), and cystic (33%). At presentation, 57% were stage ≥pT3, 52% had positive nodes, and 19% had distant metastases. After a mean follow-up of 27 months (range, 1 to 114 mo), 39% of patients were dead of disease, and 26% had disease progression. We conclude that FH and 2SC are useful IHC ancillary tools, which allow recognition of FH-deficient RCC.
- MeSH
- čipová analýza tkání MeSH
- cystein analogy a deriváty analýza biosyntéza MeSH
- dědičné nádorové syndromy diagnóza genetika patologie MeSH
- dospělí MeSH
- fumarasa nedostatek genetika MeSH
- imunohistochemie MeSH
- karcinom z renálních buněk diagnóza etiologie MeSH
- leiomyomatóza diagnóza genetika patologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- nádory dělohy diagnóza genetika patologie MeSH
- nádory kůže diagnóza genetika patologie MeSH
- nádory ledvin diagnóza etiologie MeSH
- psychomotorické poruchy komplikace MeSH
- senioři MeSH
- svalová hypotonie komplikace MeSH
- vrozené poruchy metabolismu komplikace MeSH
- zárodečné mutace MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
The P2X7 receptor (P2X7R) is a member of the ATP-gated ion channel family that exhibits distinct electrophysiological and pharmacological properties. This includes low sensitivity to ATP, lack of desensitization, a sustained current growth during prolonged receptor stimulation accompanied with development of permeability to large organic cations, and the coupling of receptor activation to cell blebbing and death. The uniquely long C-terminus of P2X7R accounts for many of these receptor-specific functions. The aim of this study was to understand the role of conserved ectodomain cysteine residues in P2X7R function. Single- and double-point threonine mutants of C119-C168, C129-C152, C135-C162, C216-C226, and C260-C269 cysteine pairs were expressed in HEK293 cells and studied using whole-cell current recording. All mutants other than C119T-P2X7R responded to initial and subsequent application of 300-μM BzATP and ATP with small amplitude monophasic currents or were practically nonfunctional. The mutagenesis-induced loss of function was due to decreased cell-surface receptor expression, as revealed by assessing levels of biotinylated mutants. Coexpression of all double mutants with the wild-type receptor had a transient or, in the case of C119T/C168T double mutant, sustained inhibitory effect on receptor trafficking. The C119T-P2X7R mutant was expressed on the plasma membrane and was fully functional with a slight decrease in the sensitivity for BzATP, indicating that interaction of liberated Cys168 with another residue rescues the trafficking of receptor. Thus, in contrast to other P2XRs, all disulfide bonds of P2X7R are individually essential for the proper receptor trafficking.
- MeSH
- cystein biosyntéza genetika fyziologie MeSH
- HEK293 buňky MeSH
- konzervovaná sekvence * MeSH
- krysa rodu rattus MeSH
- lidé MeSH
- mutace fyziologie MeSH
- purinergní receptory P2X7 genetika metabolismus MeSH
- transport proteinů fyziologie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Intramural MeSH
- MeSH
- cystein biosyntéza nedostatek terapeutické užití MeSH
- energetický metabolismus * fyziologie účinky léků MeSH
- glukosa nedostatek terapeutické užití MeSH
- glutathion biosyntéza nedostatek terapeutické užití MeSH
- glycin biosyntéza nedostatek terapeutické užití MeSH
- kyselina glutamová biosyntéza nedostatek terapeutické užití MeSH
- kyseliny mastné omega-6 biosyntéza nedostatek terapeutické užití MeSH
- lidé MeSH
- multiorgánové selhání dietoterapie prevence a kontrola terapie MeSH
- nutriční podpora * metody normy využití MeSH
- oxidační stres fyziologie imunologie účinky léků MeSH
- péče o pacienty v kritickém stavu metody trendy využití MeSH
- polytrauma * dietoterapie komplikace terapie MeSH
- rekonvalescence MeSH
- taurin biosyntéza nedostatek terapeutické užití MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přednášky MeSH
- přehledy MeSH
