MCT Flashcards
(265 cards)
What bioactive substances to MC’s contain?
Heparin, histamine, TNF-alpha and proteases
What can MCs rapidly produce when stimulated?
Chymase, tryptase, cytokines (TNF alpha, IL6) chemokines (CCL2, CXCL1) VEGF, basic fibroblast growth factor, prostaglindin D2, leukotriene C4
What was found to be a risk factor for golden retrievers with MCT?
polymorphisms in the GNAI2 gene and multiple genes assoc with hyaluronic acid synthesis
Alterations in expression of what cyclin-dependent kinase inhibitors have been identified in a many canine MCTs?
p21 and p27
What is KIT normally expressed on?
Hematopoietic stem cells, melanocytes and MCs
What does KIT bind and what does this cause?
SCF binds KIT –> KIT dimerization –> phosphorylation –> intracellular signaling –> proliferation, differentiation and maturation of normal MCs
What is essential for the differentiation of mature MC from CD34+ stem cells?
SCF (stem cell factor)
The juxtamembrane domains of kit are
exon 11-12
The extracellular domains of KIT are
exon 8-9
What do KIT mutations cause?
SCF-independent activation of KIT –> unregulated KIT signal transduction
c-kit mutations are associated with ____% of canine intermediate and high grade MCTS
25-30%
CNVs ( copy number variation) have been associated with (high/low) MCTs
High
MCTs with kit mutations showed aberrant CNVs involving what genes?
p53 and rB pathways
What drug metabolism and cell cycle pathways have been shown to correlated with cure from surgery vs. death from MCT?
solute carrier transporter and UDP glucuronosyltransferase gene families
What four stress response proteins are significantly upregulated in high-grade MCT
HSPA9 PDIA3 TCP1A TCP1E
Over expression of what micro-RNA was associated with MCT metastasis?
micro-RNA-9
What percent of dogs present with multiple MCTs?
11-14%
What is the behavior of primary GI MCT in dogs?
Aggressive - 40% alive at 30d , <10% alive at 6mo
GI ulceration has been documented in ____% of dogs undergoing necropsy
35-83% (may be selecting for higher grade tumors because necropsy)
What does histamine released from MCT act on?
H2 receptors on parietal cells –> increased HCl
In addition to high plasma histamine concentrations, dogs with MCT can also have decreased plasma ____ levels
Gastrin - normally released by antral G cells in response to increased gastric HCl
What mediates the hypotensive effects in humans with MC diseases?
Prostaglandins in the D series
What is the most consistent and reliable prognostic factor for canine MCT?
Grade
What is the long term survival rate for well-diffentiated and intermediate grade MCT after complete surgical excision
well-differentiated 80-90% Intermediate 75%