Tyrphostins. II. Heterocyclic and .alpha.-substituted benzylidenemalononitrile tyrphostins as potent inhibitors of EGF receptor and ErbB2/neu tyrosine kinases
摘要:
We have previously described a novel series of low molecular weight protein tyrosine kinase inhibitors which we named tyrphostins. The characteristic active pharmacophore of these compounds was the hydroxy-cis-benzylidenemalononitrile moiety. In this article we describe three novel groups of tyrphostins: (i) one group has the phenolic moiety of the cis-benzylidenemalononitrile replaced either with other substituted benzenes or with heteroaromatic rings, (ii) another is a series of conformationally constrained derivatives of hydroxy-cis-benzylidenemalononitriles in which the malononitrile moiety is fixed relative to the aromatic ring, and (iii) two groups of compounds in which the position trans to the benzenemalononitrile has been substituted by ketones and amides. Among the novel tyrphostins examined we found inhibitors which discriminate between the highly homologous EGF receptor kinase (HER1) and ErbB2/neu kinase (HER2). These findings may lead to selective tyrosine kinase blockers for the treatment of diseases in which ErbB2/neu is involved.
Autoimmune thyroiditis is often associated with Type 1 diabetes mellitus (T1DM). In non-obese adult-onset diabetes diagnosed initially as Type 2 diabetes mellitus (T2DM), there is a proportion of cases with so far undiagnosed T1DM. The objective of this study was to estimate the frequency of autoimmune thyroiditis (AT) among non-obese (BMI <30.0 kg/m2) patients with T2DM and to compare the frequency of AT in subgroups of patients according to the presence of glutamic acid decarboxylase antibodies (GADA), insulin requirement, and post-breakfast C-peptide levels. The study included 118 adult patients (55 men and 63 women) with the initial diagnosis of T2DM and age at the onset of diabetes > 35 yr. Median of age was 66 yr (range 39-82), and median duration of diabetes was 9 (range 1-27) yr. AT was diagnosed using thyroid peroxidase antibodies, TG-antibodies, US and TSH levels. Nineteen per cent of the subjects were found to have AT, and the frequency of AT did not significantly differ between the groups of GADA+ and GADA- subjects. There was no difference in the frequency of AT between the group treated with hypoglycemic agents and/or diet and the group requiring insulin. The frequency of AT was higher in the group with post-breakfast C-peptide levels < or = 0.8 nmol/l compared to the group with post-breakfast C-peptide levels > 0.8 nmol/l (37% vs 16%), however the group with post-breakfast C-peptide levels < or = 0.8 nmol/l had longer duration of diabetes.