Ki-67 immunostaining in node-negative stage I/II breast carcinoma. Significant correlation with prognosis.

Prognostic predictors for node-negative breast carcinoma have not been clearly established. Immunostaining with Ki-67 antibody was performed on frozen sections of histologically proved node-negative breast carcinomas from 42 patients to examine its prognostic value and its association with other clinicopathologic and biochemical parameters, i.e., patient age and tumor size, histologic type, nuclear grade, mitotic rate, presence of vascular or lymphatic invasion, DNA ploidy, percentage of cells in S-phase, estrogen content, and c-erbB-2 amplification. Thirty-seven of the 42 tumors showed immunoreactivity with Ki-67 antibody in 1% to 55% of the tumor cells. A strongly significant correlation was observed between Ki-67 staining percentage and, respectively, nuclear grade, age, and mitotic rate. Nuclear grade 1 (the most anaplastic) tumors showed a significantly higher median percentage of cells stained (median, 14; range, 3 to 40) compared with nuclear grade 3 tumors (median, 0.5; range, 0 to 8). Thirteen patients developed recurrence; six of them died of disease. On univariate analysis, both 5-year disease-free and overall survivals were strongly associated with percentage of cells stained with Ki-67 antibody. Our results suggest that Ki-67 immunostaining correlates well with nuclear grade and clinical outcome in node-negative breast carcinoma. Because of small sample size analyzed in this study we were unable to do multivariate analysis. Therefore, further studies with larger number of cases are needed to determine whether tumor proliferative activity determined by Ki-67 immunostaining is an independent prognostic parameter or it merely reflects histopathologic features such as nuclear grade or mitotic activity.

Lithium chloride stimulates human monocytes to secrete tumor necrosis factor/cachectin.

The purpose of this study was to examine the effect of lithium chloride (LiCl) on human monocytes. Patients undergoing lithium therapy have elevated white blood cell counts. Since both tumor necrosis factor alpha (TNF alpha) and interleukin 1 (IL-1), which are secreted by monocytes, can stimulate endothelial cells to produce granulocyte-macrophage colony-stimulating factor (GM-CSF), we determined whether lithium-stimulated monocytes produced TNF alpha and/or IL-1. Normal human monocytes were incubated for 24 h with medium (negative control), lipopolysaccharide (positive control), or LiCl (0.05-50 mM). The supernatants were removed and assayed for IL-1 and TNF alpha secretion using the D10.G4.01 and L929 assays, respectively. Lithium did not stimulate IL-1 secretion but did stimulate TNF alpha secretion (5-10 U/ml of TNF alpha per 2 x 10(5) monocytes). The increased secretion of TNF alpha was associated with a fourfold increase in TNF alpha mRNA. TNF alpha activity in the supernatants was neutralized by a monoclonal antibody against human TNF alpha but not by antibody against human albumin. Other alkali metals such as rubidium and cesium did not stimulate monocytes to secrete TNF alpha. These data indicate that one mechanism by which Li may cause granulocytosis is through a transcriptional enhancement of TNF production and subsequent secretion by monocytes.

Philadelphia chromosome without breakpoint cluster region rearrangement in a case of Lennert's lymphoma of suppressor phenotype.

A 60-year-old woman presented with diffuse lymphadenopathy. Diagnostic and staging work-up showed that the patient had diffuse small cleaved cell lymphoma (diffuse poorly differentiated lymphocytic lymphoma) with associated histiocytes (lymphoepithelioid cell lymphoma) by the Kiel classification system. Immunohistologic staining showed a T suppressor cell tumour phenotype. Cytogenetic studies revealed the Philadelphia chromosome (Ph1). On DNA studies, the breakpoint cluster region (BCR) gene was not rearranged suggesting that the Ph1 involvement was not identical to that seen in chronic myelogenous leukemia (CML). This case is presented because of the rarity of Ph1 in lymphoid malignancies, particularly in those of T-cell origin, and because of its potentially adverse implications.

HLA class II antigen associated invariant chain gene expression in malignant lymphoma.

Expression of the gene encoding HLA class II antigen-associated invariant chain was studied in several types of fresh human malignant lymphoma by Northern blot analysis or slot-blot analysis. The invariant chain mRNA levels decreased with the stage of B-lymphocyte differentiation to plasma cells such as in immunoblastic lymphoma (IBL) or multiple myeloma (MM). The invariant chain gene (In-gene) was expressed in diffuse large cell lymphoma (DLCL), while its expression was hardly detected in IBL. It is suggested that the difference in In-gene expression between DLCL and IBL could be useful in distinguishing these two morphologically similar diseases.

Clonal nature of Philadelphia chromosome-positive and -negative chronic myelogenous leukemia by DNA hybridization analyses.

Evidence for the clonal nature of chronic myelogenous leukemia (CML) has been obtained primarily from studies of black females expressing polymorphic glucose-6-phosphate dehydrogenase (G6PD) isoenzymes where, instead of the heterozygous pattern normally found as a result of random X chromosome inactivation, exclusive expression of only one G6PD allele has been demonstrated in leukemic cell populations. We report here the use of two other molecular approaches to examine clonality of peripheral blood cells in patients with CML. The first of these is based on the analysis of consistent differential methylation patterns associated with active and inactive X chromosomes within the region spanned by a BamHI restriction fragment length polymorphism (RFLP) at the hypoxanthine phosphoribosyltransferase (HPRT) locus. By this method, three heterozygous females gave results consistent with monoclonal origin of the disease, including one patient lacking the Philadelphia chromosome (Ph1) normally associated with CML. In the other two patients, both of whom had Ph1-positive CML, clonality was confirmed by the demonstration of simple gene rearrangements by Southern hybridization with a breakpoint cluster region (bcr) probe from chromosome 22.

The gene located at chromosome 18 band q21 is rearranged in uncultured diffuse lymphomas as well as follicular lymphomas.

The karyotypic abnormality t(14;18)(q32;q21) is reported to occur in 75% of follicular lymphomas. This translocation results in the rearrangement of a putative oncogene bcl-2, which resides at chromosome 18 band q21 (the 18q21 gene). Using two human genomic DNA fragments cloned from the chromosome 18 band q21 as probes, we analyzed 65 uncultured human lymphoma samples by the Southern blot technique. The 18q21 gene was rearranged in 18 of 26 (69%) follicular lymphomas, 3 of 5 (60%) follicular lymphomas transformed to large cell lymphomas, 8 of 20 (40%) diffuse large cell lymphomas (DLCLs), and 2 of 7 (29%) small noncleaved cell lymphomas (SNCs). Our analysis detected rearrangement of the 18q21 gene in 10 of 13 (77%) cases in which the t(14;18)(q32;q21) translocation was found by cytogenetic techniques. Our analysis also proved helpful in difficult karyotyping situations: (a) identifying the donor chromosome fragment as chromosome 18 band q21 in 4 of 9 (44%) cases that cytogenetically displayed a 14q+ chromosome of unknown origin, and (b) identifying a rearrangement of chromosome 18 band q21 in 12 of 18 (67%) cases that cytogenetically yielded no cells in metaphase. We also demonstrated three cases of submicroscopic rearrangement of the 18q21 gene. In our studies, patients with DLCLs and rearrangement of the 18q21 gene had a significantly higher incidence of extranodal involvement when compared with patients with DLCLs and no 18q21 gene rearrangement (P = 0.03).

Expression of c-fos, c-myb, and c-myc in human monocytes: correlation with monocytic differentiation.

Terminal differentiation of human monocytic leukemia cells (THP-1 cells) was associated with the induction of c-fos, the down regulation of c-myb, and no significant change in the level of c-myc expression. Gamma interferon, which resulted in a slight decrease in c-myb but no change in c-fos or c-myc expression, had a transient antiproliferative effect without a morphological or functional differentiation of THP-1 cells. Resting human peripheral blood monocytes have a high c-fos, a low c-myc, and no detectable c-myb expression. These findings suggest that a switch in c-fos/c-myb expression is associated with the terminal differentiation of cells of the monocytic lineage.

Rearrangement in the breakpoint cluster region and the clinical course in Philadelphia-negative chronic myelogenous leukemia.

We have followed one patient with Philadelphia (Ph)-negative chronic myelogenous leukemia and identified an additional four patients from the literature who showed the rearrangement in the breakpoint cluster region (bcr) on chromosome 22 characteristic of Ph-positive chronic myelogenous leukemia. The clinical course of these five patients was similar to that of Ph-positive patients, with easily controlled leukocyte counts, a prolonged benign phase, and prolonged survival. Furthermore, we have shown, for the first time, that bcr rearrangement in Ph-negative chronic myelogenous leukemia can result in expression of the aberrant 210-kilodalton bcr-abl fusion protein, which has been strongly implicated in Ph-positive leukemogenesis. Research data pertaining to possible cytogenetic mechanisms leading to production of p210bcr-abl in the absence of the Ph chromosome are reviewed. Molecular analysis provides an important tool for classifying and predicting prognosis of some patients with Ph-negative chronic myelogenous leukemia.

The c-abl, bcr and C lambda genes are amplified in a cell line but not in the uncultured cells from a patient with chronic myelogenous leukemia.

Structural alterations of the oncogenes in human tumors are reported to result from a variety of mechanisms: point mutations, chromosomal translocations and gene amplifications. In over 90% of the cases of chronic myelogenous leukemia (CML), the c-abl oncogene is translocated from chromosome 9 to chromosome 22, and forms in part the Philadelphia (Ph1) chromosome. We have molecularly analysed a double Ph1-positive (Ph1+) cell line, KBM-5 that was established from a patient with CML in the blast-transformed phase (CML-BP). We report that the c-abl, bcr, and C lambda genes are amplified approximately eight-fold in the cell line but not in the fresh uncultured cells from which KBM-5 was derived.