Applications and limitations of peripheral blood lymphocyte immunoglobulin light chain analysis in the evaluation of non-Hodgkin's lymphoma

Surface immunoglobulin (sIg) light chain analysis of peripheral blood lymphocytes (PBL) from 63 patients with non-Hodgkin's lymphoma (NHL) was performed to determine the ratio of kappa-bearing lymphocytes to lambda-bearing lymphocytes (kappa/lambda ratio). In 43% an abnormal kappa/lambda ratio was detected, implying the presence of a malignant clone in the peripheral blood (clonal excess). In 67% of cases with an abnormal kappa/lambda ratio, the absolute lymphocyte count was within normal limits and 20% did not have morphologic bone marrow involvement. Light chain analysis of bone marrow aspirates was performed in three of four patients with a circulating clone and normal bone marrow morphology. All three patients had abnormal bone marrow aspirate kappa/lambda ratios. The presence of a circulating clone was associated with morphologic bone marrow involvement (P less than 0.05). Nine patients with documented B-cell NHL were followed with repeated examinations. The presence of a circulating clone persisted in two patients refractory to therapy and in two patients otherwise believed to be in remission. Conversion to an abnormal kappa/lambda ratio occurred in two patients coincident with the development of new bone marrow involvement and in a third patient prior to the onset of frank leukemia. In three instances, the PBL light chain analyses remained within normal limits in patients with stable lymphadenopathy. The kappa/lambda ratio returned to normal in one patient responding to treatment with a partial remission, and remained within normal limits despite progression of lymphadenopathy in one patient, and local disease recurrence in another patient. These findings suggest that the detection of a circulating clone by sIg light chain analysis may be useful as a noninvasive approach to identify disseminated disease activity unsuspected on the basis of morphologic evaluations, but may not reflect the presence, progression, or recurrence of localized tissue lesions.

Differences in human skin between the epidermal growth factor receptor distribution detected by EGF binding and monoclonal antibody recognition

Two methods have been used to examine epidermal growth factor (EGF) receptor distribution in human scalp and foreskin. The first employed [125I]EGF viable explants and autoradiography to determine the EGF binding pattern while the second used a monoclonal antibody to the human EGF receptor to map the distribution on frozen skin sections of an extracellular epitope on the EGF receptor. The [125I]EGF binding experiments showed accessible, unoccupied EGF receptors to be present on the epidermal basal cells (with reduced binding to spinous cells), the basal cells of the hair shaft and sebaceous gland, the eccrine sweat glands, capillary system, and the hair follicle outer root sheath, generally similar in pattern to that previously reported for full-thickness rat skin and human epidermis. The same areas also bound EGF-R1 but in addition the monoclonal antibody recognized a cone of melanin containing presumptive cortex cells, excluding the medulla, lying around and above the upper dermal papilla of anagen hair follicles, epithelial cells around the lower dermal papilla region, and in some tissue samples the cell margins of the viable differentiating layers of the epidermis. In a control study, to clarify whether EGF-R1 could recognize molecules unrelated to the EGF receptor, the EGF binding and EGF-R1 recognition profiles were compared on cultures of SVK14 cells, a SV40 transformed human keratinocyte cell line. EGF binding and EGF-R1 monoclonal antibody distribution on these cells was found to be similar, indicating that, at least for SVK14 cells, EGF-R1 binding provides a reliable marker for EGF binding. Explanations for the discrepancies between these two methods for determining EGF receptor distribution in human skin are discussed, including the possibility that latent EGF receptors, unable to bind [125I]EGF, may be present in some differentiating epithelial compartments.

An RNA processing activity that debranches RNA lariats

The excised introns of pre-messenger RNA's (pre-mRNA's) and intron-containing splicing intermediates are in a lariat configuration in which the 5' end of the intron is covalently joined by a 2',5'-phosphodiester bond to a specific adenosine residue near the 3' end of the intron. A 2',5'-phosphodiesterase activity in HeLa cell extracts has been detected that debranches RNA lariats, converting them to linear RNA molecules by specific cleavage of the 2',5'-phosphodiester bond. This lariat debranching activity is distinct from previously reported 2',5'-phosphodiesterases with regard to its biochemical and substrate requirements as well as its stringent cleavage specificity. The debranching activity is observed only if the RNA lariats generated during in vitro processing are deproteinized and added back to the extract. These results suggest that during the normal in vitro splicing reaction the 2',5'-phosphodiester bond of RNA lariats is protected from cleavage by the lariat debranching activity.

Cryptic branch point activation allows accurate in vitro splicing of human beta-globin intron mutants

The excised introns of pre-mRNAs and intron-containing splicing intermediates are in a lariat configuration in which the 5' end of the intron is linked by a 2'-5' phosphodiester bond (RNA branch) to a single adenosine residue near the 3' end of the intron. To determine the role of the specific sequence surrounding the RNA branch, we have mutated the branch point sequence of the human beta-globin IVS1. Pre-mRNAs lacking the authentic branch point sequence are accurately spliced in vitro; processing of the mutant pre-mRNAs generates RNA lariats due to the activation of cryptic branch points within IVS1. The cryptic branch points always occur at adenosine residues, but the sequences surrounding the branched nucleotide vary. Regardless of the type of mutation or the sequences remaining within IVS1, the cryptic branch points are 22 to 37 nucleotides upstream of the 3' splice site. These results suggest that RNA branch point selection is primarily based on a mechanism that measures the distance from the 3' splice site.

Prolactin homogeneously induces the tRNA population of mouse mammary explants

Explants of mouse mammary glands were cultured with and without prolactin in the presence of inorganic [32P] to estimate the effect of prolactin on tRNA synthesis. Labeled tRNA was extracted and characterized by two-dimensional gel electrophoresis. tRNA synthesis was 2-3 fold greater in the presence of prolactin; and the synthesis rate of each resolvable tRNA species was increased proportionally. tRNA populations from mouse mammary tissues at three stages of development were also examined. Alterations were noted between early pregnant and fully lactating tissues. The results of this study provide evidence that the tRNA population, which is known to be "specialized" for casein synthesis in the mammary gland, is determined as the gland develops and prepares for lactation.

Alternating combination chemotherapy for stages III and IV ovarian carcinoma

Thirty-nine previously untreated patients with stages III and IV ovarian carcinoma were treated with debulking surgery, followed by alternating combination chemotherapy with cisplatin, Adriamycin (Adria Laboratories, Columbus, Ohio), and cyclophosphamide (PAC); and hexamethylmelamine, cyclophosphamide, methotrexate, and 5-fluorouracil (HexaCAF). Of 19 patients with measureable disease at the onset of therapy, ten (53%) had at least a partial response to chemotherapy. Seven (18% of total) patients were found to be pathologically free of disease at secondlook surgery, but four patients relapsed 19 to 31 months after initiating therapy. The median progression-free survival period of all 39 patients entered into the study is 12 months, and the median crude survival is 21 months. The PAC/HexaCAF alternating combination chemotherapy regimen may be administered with moderate toxicity, but the treatment results are not superior to those reported for PAC or HexaCAF alone in advanced ovarian carcinoma.

Combination intraperitoneal chemotherapy with cisplatin, cytarabine, and doxorubicin for refractory ovarian carcinoma and other malignancies principally confined to the peritoneal cavity

Thirty-one patients with refractory ovarian cancer and other malignancies principally confined to the abdominal cavity were treated with an intraperitoneal combination-chemotherapy regimen consisting of cisplatin (100 to 200 mg/m2), cytosine arabinoside (10(-4) to 10(-3) mol/L) and doxorubicin (2 to 18 mumol/L). Sodium thiosulfate was simultaneously administered intravenously to prevent cisplatin-induced nephrotoxicity. Eight of 26 evaluable patients demonstrated clinical response including seven of 17 (41%) with ovarian cancer refractory to frontline chemotherapy. Systemic toxicity was mild except for nausea and vomiting. Abdominal pain secondary to doxorubicin was the major complication of therapy. We conclude that combination intraperitoneal therapy with cisplatin, cytosine arabinoside, and doxorubicin can be safely administered with objective tumor responses observed in patients with ovarian cancer heavily pretreated and in individuals with other malignancies involving the peritoneal cavity. Doxorubicin-induced local pain limits the ability to administer multiple courses of this treatment regimen.

Efficient in vitro synthesis of biologically active RNA and RNA hybridization probes from plasmids containing a bacteriophage SP6 promoter

A simple and efficient method for synthesizing pure single stranded RNAs of virtually any structure is described. This in vitro transcription system is based on the unusually specific RNA synthesis by bacteriophage SP6 RNA polymerase which initiates transcription exclusively at an SP6 promoter. We have constructed convenient cloning vectors that contain an SP6 promoter immediately upstream from a polylinker sequence. Using these SP6 vectors, optimal conditions have been established for in vitro RNA synthesis. The advantages and uses of SP6 derived RNAs as probes for nucleic acid blot and solution hybridizations are demonstrated. We show that single stranded RNA probes of a high specific activity are easy to prepare and can significantly increase the sensitivity of nucleic acid hybridization methods. Furthermore, the SP6 transcription system can be used to prepare RNA substrates for studies on RNA processing (1,5,9) and translation (see accompanying paper).

Excision of an intact intron as a novel lariat structure during pre-mRNA splicing in vitro

To study the mechanisms of RNA splicing we have analyzed the products generated by in vitro processing of a truncated 32P-labeled human beta-globin RNA precursor that contains the first two exons and the first intervening sequence (IVS1). Six major RNA products were detected and characterized. The first detectable RNA processing event is cleavage at the 5' GT of IVS1. Subsequently, accurately spliced RNA and the excised, intact IVS1 are simultaneously observed. The IVS1-containing RNA processing products have several unusual properties, which include: anomalous electrophoretic mobilities on polyacrylamide gels; a block to reverse transcription near the 3' end of IVS1; the presence of a nuclease-resistant component within IVS1. The block to reverse transcription and the nuclease-resistant component map to the same site near the 3' end of IVS1. The nuclease-resistant component appears to be a modified adenosine residue that contains an RNA branch. Based upon these and other structural studies we propose that the 5' end of IVS1 is joined by a 2'-5' phosphodiester linkage to the A residue in the RNAase T1 oligonucleotide ACTCTCTCTG located 28-37 nucleotides upstream from the IVS1 3' end. The IVS1 is therefore in the form of a lariat. These results imply that sequences within IVS1 actively participate in splicing.

Distribution of epidermal growth factor receptors in rat tissues during embryonic skin development, hair formation, and the adult hair growth cycle

In a previous study on neonatal rat skin (Green MR, Basketter DA, Couchman JR, Rees DA: Dev Biol 100:506-512, 1983) a close positive correlation was found between epidermal growth factor (EGF) receptor tissue distribution and areas of potential epithelial cell proliferation. We now report on the binding distribution of [125I]EGF, representing the tissue localization of available EGF receptors, during embryonic rat skin development including hair follicle formation and the adult hair growth cycle. At 16 days embryonic development a relatively low receptor density is seen over all the epidermal cell layers but by 17 days, with the onset of very rapid epidermal proliferation, labeling increases and becomes restricted to the basal epidermal cells. Between 17 and 20 days embryonic development, available receptors for EGF are consistently absent from epidermal basal cells overlaying the dermal condensates marking the first stage of hair follicle development. This restricted and temporary loss of EGF receptors above these specialized mesenchymal condensates implies a role for the EGF receptor and possibly EGF or an EGF-like ligand in stimulating the epithelial downgrowth required for hair follicle development. In the anagen hair bulb, receptors for EGF are detected over the outer root sheath and the epithelial cell layers at the base of the follicle and show a correlation with the areas of epithelial proliferation in the hair bulb. During the catagen and telogen phases of the hair cycle, receptors are observed in high numbers on all the undifferentiated or dedifferentiating cells of the degenerating epithelial strand and secondary hair germ. Dermal cells are, in general, less heavily labeled than the basal epithelial cells of skin except for the developing striated muscle (panniculus carnosus) in embryonic skin which is more heavily labeled. The data are discussed in terms of a possible role for the EGF receptor and associated EGF or EGF-like ligands in specific areas of epithelial tissue morphogenesis during embryonic skin maturation, hair follicle development, and hair cycling.

The treatment of melanoma with m-AMSA A Cancer and Leukemia Group B phase II study

The activity of m-AMSA was evaluated IN 39 patients with advanced malignant melanoma. Seventy-nine percent of the patients had some prior chemotherapy. The others had some combination of surgery, radiotherapy, and immunotherapy prior to this study. Patients were treated every 3 weeks starting with 60 or 120 mg/m2 of m-AMSA depending on the extent of prior treatment. Doses were escalated if nadir WBC counts were greater than 2500/microliter. Leukopenia was the dose-limiting toxicity with 7.5% of patients having nadir WBC counts less than 1000/microliter. Of the 39 patients evaluable for response, all had progressive disease. In this study, m-AMSA in myelosuppressive doses was not active in malignant melanoma.

Normal and mutant human beta-globin pre-mRNAs are faithfully and efficiently spliced in vitro

Human beta-globin mRNA precursors (pre-mRNAs) synthesized in vitro from a bacteriophage SP6 promoter/beta-globin gene fusion are accurately and efficiently spliced when added to a HeLa cell nuclear extract. Under optimal conditions, the first intervening sequence (IVS 1) is removed by splicing in up to 90% of the input pre-mRNA. Splicing requires ATP and in its absence the pre-mRNA is neither spliced nor cleaved at splice junctions. Splicing does not require that the pre-mRNA contain a correct 5' or 3' end, a 3' poly A tail, or a 5'-terminal cap structure. However, capping of the pre-mRNA significantly affects the specificity of in vitro processing. In the absence of a cap approximately 30%-40% of the pre-mRNA is accurately spliced, and a number of aberrantly cleaved RNAs are also detected. In contrast, capped pre-mRNAs are spliced more efficiently and produce fewer aberrant RNA species. The specificity of splice-site selection in vitro was tested by analyzing pre-mRNAs that contain beta-thalassemia splicing mutations in IVS 1. Remarkably, these mutations cause the same abnormal splicing events in vitro and in vivo. The ability to synthesize mutant pre-mRNAs and study their splicing in a faithful in vitro system provides a powerful approach to determine the mechanisms of RNA splice-site selection.

Adenocarcinoma of the fallopian tube: Report of a case with an unusual pattern of metastasis and response to combination chemotherapy

A patient with stage I fallopian tube adenocarcinoma had disease recurrence in both lungs shortly after completing adjuvant therapy with intraperitoneal 32P and parenteral cyclophosphamide. She achieved a complete clinical response to cisplatin, Adriamycin, and cyclophosphamide (PAC) chemotherapy, but was subsequently found to have brain metastasis. The implications of these observations for understanding the natural history and optimal therapy of this disease are discussed.

Combination Intracavitary Chemotherapy for Malignant Pleural Disease

Seven previously heavily pretreated patients with malignant pleural disease and effusions were treated with 12 courses of combination intrapleural chemotherapy with cisplatin, cytarabine, and doxorubicin. Two patients with ovarian cancer metastatic to the pleura demonstrated dramatic clinical improvement following therapy. Local pain, nephrotoxicity, or bone marrow suppression were not observed during this trial. Further investigation of intrapleural therapy utilizing an escalated dose of cytarabine is warranted.

Pharmacokinetics and toxicity of 5-day continuous infusion of vinblastine

Ten patients with advanced cancer were treated in a phase-I trial with monthly cycles of a 5-day infusion of vinblastine. Serum drug levels were relatively constant after 24 h and there was no correlation between drug level and myelosuppression or toxicity. Previously undescribed toxicities were observed, including one hypersensitivity reaction and three cases of severe, only slowly reversible, sensorimotor neuropathy. Two patients showed objective tumor regression during the vinblastine infusion therapy.

Distribution and number of epidermal growth factor receptors in skin is related to epithelial cell growth

Epidermal growth factor (EGF), a low-molecular-weight polypeptide (G. Carpenter and S. Cohen, 1979, Annu. Rev. Biochem. 48, 193-216), stimulates the proliferation and keratinisation of cultured embryonic epidermis (S. Cohen, 1965, Dev. Biol. 12, 394-407) and promotes epidermal growth, thickening, and keratinisation when injected into neonatal mice (S. Cohen and G.A. Elliott, 1963, J. Invest. Dermatol, 40, 1-5). We have determined the distribution of the available receptors for epidermal growth factor in rat skin using autoradiography following incubation of explants with 125I-labelled mouse EGF. EGF receptors are detected on the epithelial cells overlying the basement membranes of the epidermis, sebaceous gland, and regions of the hair follicle all of which have proliferative capacity. In marked contrast, tissues which have started to differentiate and lost their growth potential, carry either an undetectable or sharply reduced number of EGF receptors. The EGF receptor number and receptor affinity of epidermal basal cells freshly isolated from rats of increasing age has also been determined. We find that receptor affinity remains unchanged (3.3 nM) but that basal cell surface receptor number decreases markedly with age. This decrease in receptor number is similar in trend to the known drop in basal cell [3H]thymidine labelling index which occurs over the same time period. The data suggest that the distribution of EGF receptors and EGF cell surface receptor number in skin are important in the spatial and temporal control of epithelial proliferation.

cis and trans activation of globin gene transcription in transient assays

We examined the effects of the simian virus 40 enhancer sequence on transcription of cloned human alpha- and beta-globin genes shortly after their introduction into cultured mammalian cells. We find that (i) detectable transcription of the beta-globin gene but not the alpha-globin gene requires linkage to the enhancer; (ii) the enhancer increases the amount of beta-globin RNA at least 100-fold but results in only a 5- to 10-fold increase in the amount of alpha-globin RNA; (iii) plasmid replication does not increase the level of beta-globin RNA, regardless of linkage to the enhancer, but does result in an approximately equal to 50-fold increase in the level of alpha-globin RNA; (iv) the enhancer is not required for and does not increase transcription of either gene in 293 cells, an adenovirus 5-transformed human kidney cell line. We also show that an enhancer sequence is not required for activity of the normally enhancer-dependent simian virus 40 early promoter in 293 cells, indicating that these cells contain a trans-acting factor(s) that circumvents the requirement for the enhancer sequence.

Transcriptional activation of cloned human beta-globin genes by viral immediate-early gene products

When the human beta-globin gene is transfected into Hela cells, no beta-globin RNA is detected unless the gene is linked to a viral transcription enhancer. In this paper we show that trans-acting adenovirus and herpesvirus (pseudorabies) transcriptional regulatory proteins can circumvent this enhancer requirement for detectable beta-globin transcription in transient expression assays. The viral gene products can be provided by constitutively expressed, integrated viral genes in established cell lines, by viral infection of permissive cells, or by transfection of cells with bacterial plasmids carrying the viral immediate-early genes. These results demonstrate the utility of transient expression assays for studying regulatory mechanisms involving trans-acting factors. Analysis of beta-globin promoter mutants indicates that between 75 and 128 bp of sequence 5' to the mRNA cap site is required for enhancer-dependent transcription in Hela cells. In contrast, beta-globin transcription in the presence of viral immediate-early gene products requires only 36 bp of 5'-flanking sequence, which includes the TATA box. Thus both cis and trans-acting viral factors activate beta-globin gene transcription in transient expression experiments, but the mechanisms by which they act appear to be fundamentally different.

Detection in milk of a 60,000 Mr mouse and a 68,000 Mr human phosphorylated glycoprotein by histochemical analysis on polyacrylamide gels

Proteins in colostrum and skimmed milk from humans and mice were separated by electrophoresis on polyacrylamide gels and stained with Coomassie blue (CB), Ethyl-Stains-all (ESA), and periodic acid-Schiff (PAS) to investigate changes that may occur in milks throughout lactation. In mouse colostrum but not in mature mouse milk, a PAS-positive protein of apparent molecular weight of 60,000 stained prominently blue with ESA. A protein in human milk with a molecular weight of 68,000 stained similarly but was present throughout lactation. The intensity of blue staining of these minor proteins in milk approached that obtained with casein phosphoproteins. The metachromatic dye ESA stains phosphoproteins and sialic acid-rich glycoproteins blue to blue-green. Removal of phosphorus from the former and sialic acid from the latter results in those proteins staining red with ESA. The intensity of blue staining of the 60,000 and 68,000 Mr proteins was diminished but not lost following treatment with phosphatase. It was eliminated following neuraminidase digestion of the mouse protein and mild acid hydrolysis of the human protein. Coomassie blue staining of the proteins was not affected by these procedures. Following electrophoresis of milk and milk fractions in a non-sodium dodecyl sulfate-containing system, the proteins were identified by their characteristic staining properties with ESA and isolated.

Human beta-globin pre-mRNA synthesized in vitro is accurately spliced in Xenopus oocyte nuclei

To study the mechanisms of RNA splicing we have synthesized beta-globin mRNA precursors by in vitro transcription using a plasmid in which a human beta-globin gene is fused to an efficient bacteriophage promoter. The structural requirements for accurate splicing of the in vitro synthesized pre-mRNAs were investigated by injection into Xenopus oocyte nuclei. We detect splicing only if the pre-mRNA is capped in vitro prior to injection; uncapped RNA is rapidly degraded. In addition, we find that in vitro synthesized pre-mRNAs that are not polyadenylated or lack a normal 3' end are spliced following injection into oocytes. The observation that a purified pre-mRNA can be spliced in oocytes indicates that transcription and splicing are not obligatorily coupled. When an in vitro synthesized beta-globin pre-mRNA containing a splice junction mutation is microinjected, the affected junction is not spliced, indicating that sequences necessary for accurate splicing in human cells are also necessary for splicing in oocytes.

Chronic lymphocytic leukemia and other chronic lymphoid proliferations: surface marker phenotypes and clinical correlations

A diagnosis of chronic lymphocytic leukemia (CLL) was made in 81 patients referred for peripheral blood lymphocyte typing (PBL). A retrospective review was undertaken to see if correlations existed between surface marker phenotype-determined subclasses and clinical features. Surface markers utilized were surface immunoglobulin (sIg), sheep erythrocyte receptor (E), 65,000-dalton human T lymphocyte antigen (T65), Ia antigen, and for sIg+ cells, heavy and light chains. All patients were Ia+. Cells of 70% of patients were sIg+ E- T65+ Ia+, and the clinical heterogeneity was that of classical CLL. Eight of the nine patients with sIg+ E- T65- Ia+ cells had a paraprotein. The sIg- E+ T65+ Ia+ phenotype represented classical T cell CLL. Three of the five patients in the sEg- E- T65+ Ia+ group had significant albuminuria, and two had nephrotic-range proteinuria. Use of additional monoclonal antibodies to B cell surface antigens should further subclassify CLL and other lymphoproliferative disorders. Interesting clinical correlations with certain phenotypic subclasses do exist, and further subclassification and long-term follow-up may yield correlations between phenotypes and prognosis.