CD27-CD70 Interaction: Unravelling its Implication in Normal and Neoplastic B-Cell Growth

Members of the Tumour Necrosis Factor-Receptor (TNFR) family play an essential role in the control of lymphoid cell growth and differentiation. The ligand of one of its lymphoid-specific members, CD27, was recently characterized as CD70, a type II transmembrane molecule with homology to TNF that is expressed on activated T and B cells. Ligation of CD27 by its natural ligand generates a potent costimulatory signal for cytokine production and proliferation of activated T cells. In contrast to normal B cells, where CD27 expression is confined to germinal centre cells and to a small subset of circulating B lymphocytes, CD27 expression is found on a large array of distinct B-cell neoplasia. Here, we review recent data on the expression and function of TNFR family members on normal and malignant lymphocytes and propose a role for CD27-CD70 interaction in B-cell development.     

Protein kinases in human breast cancer

Summary The family of protein kinases includes many oncogenes and growth factor receptors, many of which have been linked to the pathogenesis and progression of cancer. Protein tyrosine kinases such as HER-2/c-erbB-2 and the epidermal growth factor receptor (EGFR) have been linked specifically to breast cancer, and perturbations of HER-2 affect response to chemotherapy. We have reviewed the biology of protein kinases in human breast cancer, as well as their translational applications to breast cancer patients. We have studied the spectrum of protein kinases expressed in human breast cancer cells and have identified four protein kinases with potentially important functions in breast cancer:rak (src-related), TK5 (which we now designate JAK3), the focal adhesion kinase (FAK), and STK1 (human M015/CAK). We describe the potential significance of these genes in breast cancer, as well as our methodology for identifying and characterizing novel genes in breast cancer.     

FAMILY AND SCHOOL INFLUENCES ON COGNITIVE DEVELOPMENT

Family and school influences on cognitive development are reviewed in terms of the empirical research findings on (i) variations within the ordinary environment; (ii) family intervention studies; (iii) the effects of abnormal environments; (iv) extreme environmental conditions; (v) variations within the ordinary school environment; and (vi) preschool and school intervention studies. It is concluded that environmental effects on IQ are relatively modest within the normal range of environments, but that the effects of markedly disadvantageous circumstances are very substantial. Cognitive development is influenced both by direct effects on cognition and by indirect effects through alterations in self-concept, aspirations, attitudes to learning and styles of interaction with other people.     

A model of community substituted consent for research on the vulnerable

Persons of diminished capacity, especially those who are still legally competent but are de facto incompetent should still be able to participate in moderately risky research projects that benefit the class of persons with similar diseases. It is argued that this view can be supported with a modified communitarianism, a philosophy ofmedicine that holds that health care is a joint responsibility that meets foundational human needs. The mechanism for obtaining a substituted consent I call ``community consent,' and distinguish this from the usual family or surrogate consent for treatment. Care givers are included in the community that might consent for an individual who has no identifiable family members.     

Proliferation of the breast epithelium in relation to menstrual cycle phase,hormonal use,and reproductive factors

Summary The proliferative rate in normal breast epithelium from 58 women undergoing reduction mammoplastics was studied using the formalin resistant antibody Ki-S5, and related to age at operation, menstrual cycle phase, family history of breast cancer, height and weight, parity, and hormonal use.The breast tissue from women operated on in the luteal menstrual cycle phase (day 15–28 among oral contraceptive (OC) users) had significantly higher proliferative rate than breast tissue removed from women in the follicular phase (day 1–14) (p = 0.01). Among women presently exposed to hormones, those with a positive family history of breast cancer among first and second degree relatives had significantly higher values than cases without such history (p = 0.02). Weight was not significantly related to proliferation rate, while a short height was associated with a significantly higher proliferation rate (p = 0.04). Women who used OCs before the first full-term pregnancy (FFTP) had a significantly higher proliferation rate compared with never users or late users (p = 0.04). No significant difference was seen between parous versus nulliparous women.The results from the univariate analysis persisted in multivariate models. An especially high proliferation rate was seen in young women with both a positive family history and present hormonal use (p = 0.001). Overall, it was found that young women had a non-significantly higher proliferation rate than older women (p = 0.10). Due to small sample size, these results must be regarded as preliminary, especially in the subgroup analyses.     

THE INFLUENCE OF DOWN''S SYNDROME ON SIBLING INTERACTION

Home observations were done on sibling interactions in 31 families with a child having Down's syndrome and a non-handicapped sibling. The siblings with Down's syndrome initiated less prosocial and agonistic behaviour, but imitated more frequently than their non-handicapped siblings. These effects were found regardless of birth order. There were no effects of gender. Higher levels of prosocial behaviours among large interval dyads and in dyads with a second-born Down's syndrome child were primarily due to the age of the non-handicapped sibling. Results were similar to those in previous "normative" studies of sibling interactions.     

Effects of childhood exposure to familial alcoholism and family violence on adolescent substance use,conduct problems,and self-esteem

Exposure to familial alcoholism has been associated with many behavioral and emotional difficulties among offspring. However, few studies have examined environmental risks that often coexist with familial alcoholism, and which may influence the development of offspring psychosocial problems. This study examined potential additive and interactive effects of childhood exposure to family violence and childhood exposure to familial alcoholism on adolescent functioning. Three domains of adolescent functioning were examined in a high-risk community sample of 109 families: lifetime levels of substance use, conduct disorder behaviors, and self-esteem. Results indicated that both childhood exposure to familial alcoholism and childhood exposure to family violence were associated with psychosocial functioning of offspring during adolescence, although the relations differ according to domain of functioning and gender.     

Characterization of lymphocyte beta 2-adrenoceptor signalling in patients with left ventricular volume overload disease

1. Studies using animal experimental models have suggested that the beta2-adrenoceptor is uncoupled in association with alterations in the expression of G-protein-coupled receptor kinases (GRK) 2/3 in heart failure. However, the functional expression of the components of this pathway in human disease has not been fully elucidated yet. In the present study, we evaluated the possibility that the regulation of beta2-adrenoceptor signalling components in patients with left ventricular volume overload (VOL) depends on the severity of the overload. 2. We characterized the lymphocyte GRK 2-6, beta-arrestins 1 and 2, beta2-adrenoceptor expression at the mRNA and protein levels, as well as the activity of adenylyl cyclase, protein kinases (PK) A and PKC in patients with VOL using healthy blood donors as controls. 3. In the patient group, GRK2 mRNA was increased by 61% (P < 0.001), GRK3 was increased by 54% (P < 0.005), GRK5 was increased fivefold (P < 0.001) and the beta-arrestin 2 mRNA was increased by 40% (P < 0.05). These increases were paralleled with a sixfold increase in GRK2, a twofold increase in GRK3 and a 1.3-fold increase in GRK5 protein levels. These changes were associated with a significant decrease in beta2-adrenoceptor mRNA, the basal, catalytic and receptor-mediated activity of adenylyl cyclase and sensitization of the forskolin-stimulated activity towards augmented inhibition by guanylimidodiphosphate. In general, the increase in GRK2 and 5 mRNA exhibited a positive correlation with the gravity of the haemodynamic load, as determined by changes in left ventricular fractional shortening. 4. The results suggest that VOL induces an increase in the expression of lymphocyte beta2-adrenoceptor-specific GRK and beta-arrestin 2 in association with an attenuation in beta2-adrenoceptor levels. It can be speculated that the cardiac circulatory system adapts itself to altered haemodynamic functional demands partly by altering beta2-adrenoceptor signalling.