Block sequential adriamycin CMF--optimal non-myeloablative chemotherapy for high risk adjuvant breast cancer?

After the publication of the 10-year survival data from Milan on the adjuvant use of the block sequential regimen consisting of four cycles of adriamycin followed by eight cycles of intravenous CMF, many centres adopted this as standard of care for high risk, multiple node-positive breast cancer. For this reason it was identified as the standard arm for the Anglo-Celtic adjuvant high-dose chemotherapy trial. This study reports on the experience of this regimen in 329 women with early breast cancer involving at least four axillary nodes, who were treated outside any adjuvant chemotherapy trial. At a median follow-up of 3 years, the overall 5-year disease-free survival is 61%, and the overall survival is 70%. These data confirm the efficacy of this regimen in non-trial patients, and, for the same high risk subgroup, indicate that this approach offers an outcome at least as good as that seen in the CALGB 9344 AC-Taxol arm, and the NCIC days 1 and 8 CEF.

Late results of surveillance of clinical stage I nonseminoma germ cell testicular tumours: 17 years' experience in a national study in New Zealand.

OBJECTIVE: To re-evaluate a national prospective study in New Zealand after 17 years to define whether orchidectomy alone and surveillance for nonseminoma germ cell testicular tumour (NSGCTT) is a sound policy and matches the results achieved by other treatment protocols. PATIENTS AND METHODS: Between 1980 and 1997, 248 men with stage I NSGCTT, from six New Zealand centres, were managed by orchidectomy alone and surveillance, with treatment of relapses using combination chemotherapy. RESULTS: Seventy of the 248 patients (28%) relapsed; 42 of 92 (46%) with vascular and/or lymphatic invasion (VLI) in the primary tumour relapsed, whereas only 26 of 151 (17%) without this feature relapsed (P<0.001). VLI was the only identifiable risk factor for relapse in this series. Only one relapse occurred >28 months after orchidectomy. Despite poor compliance in some patients (12%) their survival was not prejudiced. Three patients died from disease despite chemotherapy at relapse. At 17 years and a median follow-up of 53 months, 242 of the 248 men are disease-free and the disease-specific survival rate is 98%. CONCLUSIONS: This study shows that orchidectomy alone and treatment of relapses produces excellent long-term results without the adverse effects associated with retroperitoneal node dissection or elective chemotherapy for high-risk cases.

Expression of v-src in T cells correlates with nuclear expression of NF-kappa B.

NF-kappa B is a rapidly inducible transcriptional activator that responds to a variety of signals and influences the expression of many genes involved in the immune response. Protein tyrosine kinases transmit signals from cytokine and immune receptors. Very little information exists linking these two important classes of signaling molecules. We now demonstrate that v-src expression correlates with nuclear expression of a kappa B binding complex similar to that induced by phorbol ester and ionomycin, as detected by electrophoretic mobility shift assay using a variety of kappa B sites. This complex was blocked by the tyrosine kinase inhibitor, herbimycin A. The v-src-induced complex comprised the p50 and p65 components of NF-kappa B, as determined by supershift and immunoblot analysis. As a functional correlate of this finding, transient co-transfection of HIV-1 LTR reporter constructs in a different T cell line demonstrated that v-src activated this promoter in a kappa B-dependent manner. We found that transactivation of the HIV-1 LTR by v-src was more sensitive to mutations of the proximal, rather than the distal, kappa B element. The implications for T cell receptor signaling and HIV-1 gene expression are considered.

Expression of the human epidermal growth factor receptor in a murine T-cell hybridoma. A transmembrane protein tyrosine kinase can synergize with the T-cell antigen receptor.

Although the T-cell receptor for antigen (TCR) lacks intrinsic kinase activity, stimulation of this receptor induces tyrosine phosphorylation of multiple substrates. In contrast, the epidermal growth factor receptor (EGFR) has intrinsic cytoplasmic tyrosine kinase catalytic activity that is activated upon EGF binding. To compare the functional effects of the TCR and a transmembrane protein tyrosine kinase (PTK), we used retrovirus-mediated gene transduction to express the human c-erbB proto-oncogene, encoding the EGFR, in a murine T-cell hybridoma. Tyrosine phosphorylation induced by the TCR and the EGFR occurred on substrates unique to each receptor as well as on several shared substrates, including the zeta chain of the TCR. Stimulation of the EGFR induced calcium ion flux in these cells, suggesting that the heterologous tyrosine kinase can couple to the T-cell phospholipase signal transduction pathway, but this stimulus did not lead to interleukin 2 production. However, EGF stimulation of transduced cells significantly enhanced TCR signaling, as assessed by interleukin 2 production, indicating that cross talk can occur between the TCR and a transmembrane PTK.

Characterization of the family of dimers associated with Fc receptors (Fc epsilon RI and Fc gamma RIII).

The receptor for IgE (Fc epsilon RI) is a multimeric complex containing one alpha chain, one beta chain with four transmembrane domains and one homodimer of disulfide-linked gamma-chains. The Fc epsilon RI gamma-chains form additional disulfide-linked dimers with the homologous zeta- and eta-chains, as part of the TCR complex. The low affinity receptor for IgG (Fc gamma RIII)2 on NK cells is also associated with zeta-chains. Here we show that the gamma-chain is expressed in NK cells both as a group of heterogenous gamma gamma homodimers and also as a heterodimer bound to zeta. Fc gamma RIIIA is associated with three types of dimers zeta zeta, gamma zeta, and notably gamma gamma as well. In fact, gamma gamma appears to be the predominant species associating with Fc gamma RIIIA. The surface expressed Fc epsilon RI also associates with the same group of heterogenous gamma gamma homodimers. We also show that there is no C-terminal posttranslational cleavage of gamma occurring before its insertion into the plasma membrane as previously suggested. Thus, like the TCR, Fc gamma RIIIA may form a variety of receptor isoforms, though at present we do not understand the functional implications of these structures.

The early diagnosis of acute myocardial infarction.

Latex agglutination for serum myoglobin (Rapitex) was compared with the initial ECG for the early diagnosis of acute myocardial infarction. Forty patients suspected of myocardial infarction were prospectively evaluated by initial electrocardiogram and Rapitex serum myoglobin. The initial ECG was categorised into one of three groups: Group 1 had ST segment elevation of at least 1 mm in a limb lead or 2 mm in a precordial lead (with or without Q waves); Group 2 had abnormalities other than those seen in Group 1; and Group 3 had no particular abnormalities present that is, a normal ECG. Myocardial infarction was confirmed by a rise in creatine kinase to greater than or equal to twice the upper limit of normal for our laboratory range and with a CKMB fraction of greater than 6%. Nineteen of 40 patients sustained myocardial infarction; nine ECG group 1, six ECG group 2, and four ECG group 3. Eleven of the 19 patients with myocardial infarction had positive serum myoglobin agglutination. The initial ECG was the most predictive of a subsequent rise in CK (p = 0.003), while Rapitex serum myoglobin determination was the least predictive (p = 0.8517). We conclude that the Rapitex serum myoglobin test offers little diagnostic or economic advantage over the initial electrocardiogram.

Mechanistic studies of transforming growth factor-beta inhibition of IL-2-dependent activation of CD3- large granular lymphocyte functions. Regulation of IL-2R beta (p75) signal transduction.

CD3- large granular lymphocyte (LGL) express constitutive levels of functional IL-2R beta. TGF-beta inhibited several IL-2R beta-mediated events in LGL, including IL-2-induced NK and lymphokine-activating factor activities, IFN-gamma gene expression and secretion, and IL-2R alpha expression. TGF-beta inhibited these IL-2-induced LGL functions in a dose-dependent and reversible manner. By contrast, TGF-beta had little effect on LGL IL-2R beta expression and TGF-beta receptors were not induced by IL-2. Studies were performed to examine binding and internalization of radiolabeled IL-2. These experiments demonstrated that the rapid binding and internalization of [125I]IL-2 was not altered in CD3- LGL pretreated with TGF-beta. These internalization studies indicated that the TGF-beta inhibition represented postreceptor-binding events in NK cells. Further studies were initiated to examine signaling events in CD3- LGL. When IL-2-induced tyrosine phosphorylation events were examined, significant inhibition was seen of selected phosphoproteins in TGF-beta-pretreated cells. In addition, the ability of TGF-beta to also inhibit IL-2 induction of LGL IL-2R alpha and IFN-gamma mRNA expression was consistent with the hypothesis that posttranscriptional mechanisms were unlikely to be affected by TGF-beta. Collectively, these data indicated that TGF-beta inhibited IL-2-induced CD3- LGL functions and suggested that TGF-beta inhibition occurs either at the level of specific tyrosine phosphorylation and/or IL-2-induced transcriptional control factors.

Engagement of the natural killer cell IgG Fc receptor results in tyrosine phosphorylation of the zeta chain.

The zeta chain has emerged to be a key subunit of the T-cell antigen receptor with central roles not only in intracellular assembly of the multimeric receptor but also in mediating signal transduction events. This subunit is present in natural killer (NK) cells that lack the other subunits of the T-cell antigen receptor. In NK cells, the zeta chain appears to be associated with the NK Fc receptor [type 3 receptor for the Fc portion of IgG (Fc gamma RIII or CD16)] and may be necessary for efficient cell surface expression of this receptor complex. In T cells, the zeta chain is a prominent substrate that becomes phosphorylated on tyrosine residues after occupancy of the TCR; zeta chain phosphorylation was in fact the first evidence that the TCR was coupled to a protein-tyrosine kinase as well as to inositol phospholipid hydrolysis. To determine if Fc gamma RIII is coupled to a protein-tyrosine kinase in a manner analogous to the T-cell antigen receptor, we investigated ligand-dependent zeta-chain phosphorylation in NK cells. We observed that activation of NK cells with an anti-Fc gamma RIII monoclonal antibody induced tyrosine phosphorylation of the zeta chain whereas other activating stimuli, such as the combination of phorbol ester and ionomycin or a lymphokine, interleukin 2, did not result in phosphorylation of this protein. Perturbation of Fc gamma RIII by the more physiological stimulus, incubation of NK cells with antibody-coated target cells, also induced zeta-chain phosphorylation. Previous data have indicated that the NK-cell Fc gamma RIII is coupled to inositol phospholipid hydrolysis. This present finding that Fc gamma RIII is coupled to a protein-tyrosine kinase illustrates that there are significant similarities in the signaling pathways activated by Fc gamma RIII in NK cells and the T-cell antigen receptor in T cells; the zeta chain is a common element that may serve as a coupling protein for both of these receptors.

Carboplatin is ototoxic.

For assessment of the ototoxic potential of carboplatin [cis-diammine-1,1-cyclobutane dicarboxylate platinum(II); CBDCA], pure-tone audiograms were evaluated in 27 patients receiving a total of 119 doses of carboplatin in the range of 300-400 mg/m2. Pure-tone audiometry (PTA) was done immediately prior to and 4 weeks after the administration of 80 doses (67%). Defining carboplatin ototoxicity as an increase of greater than or equal to 30 dB in auditory thresholds that was unexplainable by other causes, we identified 5 examples (19%). Hearing loss tended to be cumulative with increasing dose and was always maximal at 8,000 Hz. Two patients had an increase in auditory thresholds at 1,000 Hz, but this only amounted to 10 dB in each case. Patients developing ototoxicity tended to be older. Sex, the pre-treatment creatinine clearance, the pretreatment audiogram, the number of doses, and the cumulative dose did not emerge as being reliable predictors of subsequent ototoxicity. We conclude that although carboplatin is ototoxic, clinically significant deafness does not occur with conventional dosing and routine audiometric monitoring is therefore unnecessary. However, we suggest that caution should be exercised when carboplatin is given either at higher doses or for longer periods when there is concomitant use of other potentially ototoxic agents or when there is significant pre-existing auditory impairment.

Nodular sclerosing, mixed cellularity and lymphocyte-depleted variants of Hodgkin's disease are probable dendritic cell malignancies.

The normal counterpart of the Reed-Sternberg cell and its mononuclear variant, collectively referred to as Hodgkin's cells (HC), remains controversial. The possibility that HC are malignant dendritic cells was tested by using a panel of 38 monoclonal antibodies to phenotype the cells from 16 cases of Hodgkin's disease (HD), excluding lymphocyte-predominant HD, and the Hodgkin's cell line L428. The results were then compared with the known phenotype of human dendritic cells. HC stained strongly for HLA Class I and Class II antigens. The leucocyte common antigen was weakly expressed in most cases. Expression of T and B cell markers was unusual, with the exception of the CD40 antigen which was found on a majority of HC. HC commonly expressed the CD11a, CR4 (CD11c), CD15, CD18 and a number of activation antigens but did not stain with a variety of macrophage-specific antibodies. The antigenic phenotype of L428 and the HC of case material were similar. This immunocytological analysis failed to support a lymphocyte or macrophage origin for HC. Instead the antigenic phenotype of the Reed-Sternberg cell and its mononuclear variant more closely resembles that of dendritic cells than of any other haemopoietic cell normally resident in lymph nodes.