Soluble c-kit molecule in serum from healthy individuals and patients with haemopoietic disorders.
The proto-oncogene, c-kit, encodes a transmembrane tyrosine kinase receptor (KIT) and plays an important role in haemopoiesis. We have identified a 95 kD soluble form of KIT (S-KIT) in culture supernatant of human megakaryoblastic cell line, CMK. To study the physiological significance of S-KIT, we have established a sensitive sandwich ELISA system. Serum samples from healthy individuals contained detectable amounts of S-KIT. Next, we determined a total of 220 samples from 134 patients with haemopoietic disorders. A considerable number of patients with acute myeloid leukaemia (AML), especially those with more immature phenotypes (M0, M1 or M2) had elevated levels of serum S-KIT. Those levels decreased to the normal range after effective chemotherapy. In chronic myeloid leukaemia, patients with myeloid blastic crisis showed markedly elevated levels of serum S-KIT. In contrast, S-KIT levels decreased in cases with either acute or chronic lymphoid leukaemia. There was a tendency for patients with severe aplastic anaemia to show decreased levels, but it was not significant. In myelodysplastic syndrome, S-KIT levels appeared to vary by subsets, with higher concentration in more advanced forms of the disease. Although the functional role of S-KIT is not yet elucidated, these results suggest that the serum S-KIT levels may reflect the pathological states of various haematological disorders.
Kawakita
M
M
Second Department of Internal Medicine, Kumamoto University School of Medicine, Japan.
Yonemura
Y
Y
Miyake
H
H
Ohkubo
T
T
Asou
N
N
Hayakawa
K
K
Nakamura
M
M
Kitoh
T
T
Osawa
H
H
Takatsuki
K
K
D000208:Acute Disease; D015153:Blotting, Western; D002460:Cell Line; D004797:Enzyme-Linked Immunosorbent Assay; D006402:Hematologic Diseases / Q000097:blood*; D006801:Humans; D007938:Leukemia / Q000097:blood*; D007951:Leukemia, Myeloid / Q000097:blood / Q000188:drug therapy; D008297:Male; D008533:Megakaryocytes / Q000378:metabolism; D009190:Myelodysplastic Syndromes / Q000097:blood; D009363:Neoplasm Proteins / Q000097:blood; D000090063:Proto-Oncogene Mas; D019009:Proto-Oncogene Proteins c-kit / Q000097:blood*; D012016:Reference Values; D012995:Solubility
C000715470:MAS1 protein, human; D009363:Neoplasm Proteins; D000090063:Proto-Oncogene Mas; D019009:Proto-Oncogene Proteins c-kit