Abnormal lymphocyte protein synthesis in bronchogenic carcinoma

Variable expression of CD3-zeta and associated protein tyrosine kinases in lymphocytes from patients with myeloid malignancies

In myeloid malignancies, T-cell and NK function has been shown to deteriorate with transformation from pre-leukaemia to advanced disease. Immune dysfunction in solid tumours has been attributed to abnormal signal transduction, possibly through altered expression of intracellular components of the TCR/CD3 complex (e.g. CD3-zeta), receptors on NK cells and their associated protein tyrosine kinases (PTKs; p56lck, p59fyn and ZAP-70). Using a flow cytometric method to detect dual-expression of surface proteins and intracellular components of the TCR/CD3 complex, we have studied 46 patients with myeloid malignancies. CD3-zeta expression was abnormal in 64% of patients, and was more prominent in those with advanced disease. Three patients with reduced CD3-zeta were analysed both pre- and post-treatment, and recovery of CD3-zeta expression was associated with successful remission induction (expression of PTKs was variable and reduced levels were seen all disease stages). The results of this study suggest that loss of signalling proteins is not a result of direct contact of leukaemic cells with lymphocytes per se or the extent of the leukaemia burden, but to a specific property of some myeloid malignancies, which is more frequently acquired with greater malignant transformation.

Biologic markers in cancer diagnosis and treatment

We have reviewed several tumor markers that our advocates feel are now clinically useful, involve current assay technology, and are based on already available information. These include, in selected instances, estrogen receptors for breast cancer, thyrocalcitonin for medullary cancer of the thyroid, prostatic acid phosphatase for cancer of the prostate, alpha-fetoprotein for hepatocellular cancer, and carcinoembryonic antigen for monitoring colon cancer. We have considered the potential use of measurement of serum proteases and protein degradation products due to their activity as possible future areas of development, and we have explored measurement of tissue aryl hydrocarbon hydroxylase to identify populations at risk of cancer resulting from chemical carcinogenesis. It is clear that the study of tumor markers is already improving patient care in some specific areas and offers exciting potential for the future.

T- and B-cell responses in patients with malignant pleural effusions

Lymphocytes of lymphocyte-rich pleural effusions and venous blood from 16 cancer patients, 7 patients with benign pleural effusions and blood from 23 normal blood donors, were examined for cytological features, rosette-forming capacity, immunofluorescent staining, and PHA-stimulated DNA synthesis. Total protein and immunoglobulin levels were also determined. Metastatic effusions revealed approximately 40% higher content of immunoglobulins G, A and M (P less than 0.002) as well as of total protein (P less than 0.005) than non-metastatic pleural effusions. However, the serum of the non-cancer patients contained approximately 50% higher level of Ig than in cancer patients (P less than 0.001). Whilst there was no significant difference in the relative T- or B-cell contents of pleural effusions between cancer and non-cancer patients (P greater than 0.05) spontaneous proliferation of lymphocytes was significantly increased (P greater than 0.01), which led to a lower PHA-stimulated transformation index in pleural effusions from cancer patients than in all other lymphocyte sources examined (P less than 0.001).