Close association between interleukin 2 receptor mRNA expression and human T cell leukemia/lymphoma virus type I viral RNA expression in short-term cultured leukemic cells from adult T cell leukemia patients.

Human T cell leukemia/lymphoma (T-lymphotropic) virus type I (HTLV-I) infection has been considered to be closely associated with the leukemogenesis of adult T cell leukemia (ATL), in which interleukin 2 (IL-2) receptors are abnormally expressed. In this study, however, Southern blot analysis revealed no gross rearrangement or obvious amplification of the IL-2 receptor gene in ATL leukemic cells, indicating that abnormal IL-2 receptor expression in ATL is not due to the structural change of its gene. Hence, we studied the expression of the IL-2 receptor and HTLV-I at the RNA level during short-term cultures of leukemic cells from 9 ATL patients. Cytoplasmic dot hybridization and Northern hybridization revealed that fresh leukemic cells from seven of nine patients expressed a small amount of IL-2 receptor mRNA but HTLV-I RNA was undetectable in all cases. After cultures for up to 7 d, both IL-2 receptor mRNA and HTLV-I RNA (including pX message) expression concomitantly increased, whereas the amounts of other cellular genes, except for beta-actin, did not. The increases in their RNA expression were inhibited by early addition (within 12 h after the beginning of the culture) of cycloheximide, indicating that these increases are mediated by newly synthesized protein(s). These results strongly suggested that IL-2 receptor expression is closely associated with HTLV-I expression in leukemic cells from ATL patients.

Interleukin-2 receptor (Tac antigen) expressed on adult T cell leukemia cells.

We studied the expression of the interleukin-2 (IL-2) receptor and the proliferative response to exogenous IL-2 of peripheral blood leukemic cells from patients with adult T cell leukemia (ATL) in order to see whether IL-2 receptor expressed on ATL cells is different from normal IL-2 receptor and whether it plays a role in the neoplastic growth in ATL. Peripheral blood leukemic cells from 42 patients with ATL examined expressed IL-2 receptors that were detected by anti-Tac monoclonal antibody when examined immediately after the separation of cells or after the culture for 24 or 48 h. The number of anti-Tac binding sites ranged from 3,100 to 11,400 in fresh cells and from 3,600 to 96,000/cell in short-term cultured leukemic cells, whereas phytohemagglutinin-P (PHA-P)-stimulated normal T cells exhibited 6,900-35,000 anti-Tac binding sites per cell. ATL-derived and human T cell leukemia/lymphoma virus, type I (HTLV-I)-infected cell lines such as MT-1 and Hut102 expressed a much higher number of anti-Tac binding sites. Leukemic cells from 15 patients with ATL examined showed no or very poor proliferative response to various concentrations of immunoaffinity-purified IL-2, although they expressed Tac antigen (Ag). Radiolabeled IL-2 binding experiments demonstrated that ATL leukemic cells could bind IL-2, and they expressed both high and low affinity IL-2 receptors, although the number of high affinity IL-2 receptor was much less than that of low affinity IL-2 receptor and that of anti-Tac binding sites. In contrast, leukemic T cells from a patient with T cell chronic lymphocytic leukemia (CLL), in whom HTLV-I infection was not demonstrated, responded as well as PHA-P-stimulated normal T cells, and their IL-2 receptors, unlike ATL cells, were modulated (down regulated) by anti-Tac antibody. No differences were noted between ATL cells and normal activated T cells in one-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis of the IL-2 receptor. Thus, leukemic cells in ATL spontaneously and continuously express IL-2 receptor, which appears to be abnormally regulated and unresponsive to IL-2. These results, taken together with those on normal IL-2 receptors on HTLV-I-negative T-CLL cells, suggest that abnormal expression of the IL-2 receptor in ATL is closely associated with HTLV-I infection and may play a role in the neoplastic growth of ATL cells.

Asymptomatic normotensive primary aldosteronism. Case report.

We report a case of primary aldosteronism in a 30-year-old woman without hypertension or any other characteristic symptoms. The condition was first suspected by hypokalemia (2.6 mEq/liter), which was incidentally found by routine checkup. There was evidence of suppressed plasma renin activity (PRA) and elevated plasma aldosterone levels. However, the blood pressure never reached a hypertensive level, and the circulating blood volume was within a normal range. A functioning right adrenal tumor was diagnosed by adrenal scintigraphy, computerized x-ray tomography, and adrenal venography. Adrenal venous catheterization suggested an aldosteronoma, which was confirmed by lateralized hypersecretion of aldosterone. After removal of the benign adenoma, the biochemical abnormalities were corrected, yet the blood pressure remained much the same. Hypertension is not necessarily a sign of primary aldosteronism.

Dissociation of interleukin-2-mediated cell proliferation and interleukin-2 receptor upregulation in adult T-cell leukemia cells.

We studied cell proliferation and interleukin-2 (IL-2) receptor upregulation mediated by exogenous IL-2 in leukemic cells from adult T-cell leukemia (ATL) patients to characterize some aspects of abnormal IL-2 receptor expression in ATL. Leukemic cells from 7 ATL patients examined showed no or very poor proliferative response to IL-2 though they expressed IL-2 receptors without any stimulation. In contrast, ATL leukemic cells cultured with IL-2 for 2 days expressed about twice as many IL-2 receptors as those of cells cultured without IL-2. Thus, in ATL leukemic cells, there seems to be a dissociation between the signal(s) for two different effects mediated by IL-2, cell proliferation and IL-2 receptor upregulation.

Increase in cytoplasmic free calcium concentration initiated by T3 antigen stimulation is imparied in adult T-cell leukemia cells.

We studied the change in cytoplasmic free calcium ion concentration ([Ca2+]i) in the peripheral blood leukemic cells from adult T-cell leukemia (ATL) patients stimulated by anti-T3 (CD3) or anti-T11 (CD2) antibodies in order to see whether there is an abnormal response in the early activation processes following T3 or T11 antigen stimulation. Peripheral blood mononuclear cells (PBMC) from four T-cell chronic lymphocytic leukemia (T-CLL) patients showed a rapid and clear increase in [Ca2+]i (from 165 +/- 26 nM to more than 299 nM) when stimulated by OKT3 antibody and anti-mouse IgG antibody. This response was comparable to that of PBMC from 10 normal individuals (from 151 +/- 20 nM to 252 +/- 34 nM). In contrast, PBMC from 10 ATL patients showed only a slight increase in [Ca2+]i (from 137 +/- 21 nM to 176 +/- 32 nM) following T3 stimulation. The experiments with higher concentrations of OKT3 antibody suggested that this attenuated increase in [Ca2+]i in ATL cells was not exclusively due to impaired expression of T3 antigen. The [Ca2+]i increase in ATL cells induced by the stimulation with two anti-T11 antibodies recognizing different epitopes of the T11 antigen, however, was comparable to that of normal PBMC. The abnormal response of [Ca2+]i to the T-cell receptor/T3 antigen stimulation in ATL may be related to dysfunction or leukemogenesis of HTLV-I-infected cells.

Acute leukemia with two cell populations of lymphoblasts and monoblasts.

A 46-year-old man had acute leukemia with two cell populations of lymphoblasts and monoblasts (L1 and M5-b in FAB classification, respectively), which were characterized by morphological, cytochemical and cell marker studies. At the time of diagnosis about 80% blasts were terminal deoxynucleotidyl transferase (TdT) positive lymphoid cells, while the rest were TdT negative monocytoid cells. After induction chemotherapy of vindesine and prednisolone for 15 days, almost all blasts were TdT negative monocytoid cells. Therefore, an additional course of the chemotherapy with the protocol for acute nonlymphocytic leukemia was given and one month later the patient achieved complete remission.

Expression of terminal deoxynucleotidyltransferase gene in a case of adult T-cell leukemia.

A 37-year-old male from Kagoshima Prefecture was admitted with adult T-cell leukemia (ATL). Monoclonal integration of HTLV-1 proviral DNA was found, but the integration site was different from that of terminal deoxynucleotidyltransferase (TdT)-positive MT-1 cells (an ATL cell line). The ATL cells expressed enzymatically active TdT and exhibited 2100 b TdT mRNA, which corresponds to the thymus type of TdT mRNA. The same size of TdT mRNA was also detected in MT-1. Southern blot analyses revealed no differences in the gene structure of the promoter region of TdT genes between this ATL case and TdT-positive lymphoblastic leukemia cells. There is little possibility that cis-acting viral elements promote TdT gene expression by proviral integration. The activation of TdT gene in ATL may be mediated by other trans-acting factors.

Evaluation of epidermal growth factor receptor mutation status in serum DNA as a predictor of response to gefitinib (IRESSA).

The aim of this study was to evaluate the usefulness of EGFR mutation status in serum DNA as a means of predicting a benefit from gefitinib (IRESSA) therapy in Japanese patients with non-small cell lung cancer (NSCLC). We obtained pairs of tumour and serum samples from 42 patients treated with gefitinib. EGFR mutation status was determined by a direct sequencing method and by Scorpion Amplification Refractory Mutation System (ARMS) technology. EGFR mutations were detected in the tumour samples of eight patients and in the serum samples of seven patients. EGFR mutation status in the tumours and serum samples was consistent in 39 (92.9%) of the 42 pairs. EGFR mutations were strong correlations between both EGFR mutation status in the tumour samples and serum samples and objective response to gefitinib (P<0.001). Median progression-free survival time was significantly longer in the patients with EGFR mutations than in the patients without EGFR mutations (194 vs 55 days, P=0.016, in tumour samples; 174 vs 58 days, P=0.044, in serum samples). The results suggest that it is feasible to use serum DNA to detect EGFR mutation, and that it's potential as a predictor of response to, and survival on gefitinib is worthy of further evaluation.

1 alpha, 25-dihydroxyvitamin D3 enhances the up-regulation of interleukin-2 receptor (p55) by interleukin-2.

The effect of 1 alpha, 25-dihydroxyvitamin D3 (1 alpha, 25(OH)2D3) on the expression of interleukin-2 (IL-2) receptor in activated T lymphocytes was examined. 1 alpha, 25(OH)2D3 enhanced the expression of IL-2 receptor (p55, Tac peptide) in phytohemagglutinin (PHA)-stimulated (3 days) human peripheral blood mononuclear cells (PBM) only in the presence of IL-2 without affecting the proliferation of the cells. This enhancement was dependent on the concentration of both IL-2 (0-1 U/ml) and 1 alpha, 25(OH)2D3(0-10(-7)M). The addition of interleukin-1 (IL-1, 0-100 U/ml), did not enhance the expression of IL-2 receptor in these cells in the presence of IL-2. Moreover, 1 alpha, 25(OH)2D3 had the same effect on two cell lines, Kit225 (an IL-2 dependent cell line established from a patient with T cell chronic lymphocytic leukemia) and YT (an IL-2 independent natural killer (NK)-like cell line from a patient with acute lymphocytic leukemia). Thus, 1 alpha, 25(OH)2D3 enhances the up-regulation of IL-2 receptor (p55) by IL-2 not only in activated T cells but also in the NK-like cell line.

Leukemic cells from some adult T-cell leukemia patients proliferate in response to interleukin-4.

The proliferative response of fresh peripheral blood leukemic cells from eight adult T cell leukemia (ATL) patients to interleukin-4 (IL-4) was studied to determine the possibility that the IL-4-mediated T-cell growth pathway is involved in the cell growth of leukemic cells in ATL. Resting lymphocytes from ten normal individuals did not proliferate in response to IL-4. Leukemic cells from two ATL patients did not respond to interleukin-2 (IL-2) or IL-4. Leukemic cells from two patients did respond to IL-2, but not to IL-4. In contrast, a strong proliferative response was observed in the IL-4 culture, but not in the IL-2 culture in the remaining four patients. Chromosome analysis of mitotic cells, performed in one of four patients, confirmed that the cells dividing in response to IL-4 were leukemic cells, but not activated normal lymphocytes. These results indicate the activation of IL-4/IL-4 receptor system in leukemic cells from some ATL patients and suggest the possible involvement of the system in the proliferation of leukemic cells and the leukemogenesis in ATL.

Characteristics of the IL-2 receptor expressed on large granular lymphocytes from patients with abnormally expanded large granular lymphocytes. Implication of a non-Tac IL-2-binding peptide.

Large granular lymphocytes (LGL) from four patients with abnormally expanded LGL in the peripheral blood were studied regarding their receptor for IL-2. LGL from none of the cases examined expressed Tac Ag, an Il-2R glycoprotein recognized by anti-Tac mAb. However, 125I-labeled IL-2 binding experiments demonstrated that 1400 to 2800/cell IL-2 binding sites with a single affinity (K: 0.46-1.4 nM) were expressed on LGL from the four patients. The affinity was not high but about 10-fold higher than that of the low affinity IL-2R expressed on activated normal T lymphocytes. Furthermore, LGL from the four patients proliferated in response to higher concentrations of IL-2 and these responses were not inhibited by an excess amount of anti-Tac antibody. 125I-Labeled IL-2 cross-linking studies performed in two cases revealed the predominant expression of an IL-2 binding molecule with an estimated Mr of 70,000 to 75,000. After the culture with IL-2 for 48 h, expression of a small amount of Tac Ag (p55) was induced on LGL in at least three cases. These data strongly suggested that the IL-2R expressed on LGL is functional and identical to the p70, a novel IL-2 binding peptide that has been recently identified and speculated to form the high affinity IL-2R in association with the p55.

Expression of interleukin-2 receptor on T cell chronic lymphocytic leukemia cells and their response to interleukin-2.

We analyzed peripheral blood leukemic cells from six patients with T cell chronic lymphocytic leukemia (T-CLL) with monoclonal antibodies including the anti-Tac antibody, which recognizes the receptor for interleukin 2 (IL 2). The patients were divided into two groups according to the reactivity of the monoclonal antibodies. Leukemic cells from three patients with T-CLL reacted with OKT3 and T4 but not T8, whereas those from the remaining three patients reacted with OKT3 and T8 but not T4. IL 2 receptor, which is expressed on activated T cells but not on resting T cells, was preferentially expressed on T4+ T-CLL cells. The IL 2 receptor on T4+ T-CLL cells was indistinguishable from that on normal activated T cells with respect to molecular weight and downregulation by the anti-Tac antibody. Moreover, fresh T4+ T-CLL cells, but not T8+ T-CLL cells, proliferated in response to exogenous IL 2 without prior activation, and this proliferation was inhibited by the anti-Tac antibody. These results suggest that malignant growth of T4+ T-CLL cells can be regulated by IL 2 not only in vitro but also in vivo.

Abnormal expression of interleukin-2 receptor (Tac antigen) in adult T-cell leukemia.

Human T-cell leukemia/lymphoma virus type I(HTLV-I) infection appears to be closely associated with the leukemogenesis of adult T-cell leukemia (ATL), although its mechanism remains unclear. Since our previous report that leukemic cells from patients with ATL expressed Tac antigen (Ag) (interleukin-2 (IL-2) receptor) on their cell surface, we have been studying IL-2 receptors on ATL leukemic cells to see whether they are different from normal IL-2 receptors and whether they play a role in the neoplastic growth of ATL cells. Peripheral blood leukemic cells from 35 patients with ATL expressed IL-2 receptors which were detected by anti-Tac monoclonal antibody when examined immediately after the separation of cells or after culture for 24 or 48 hr. The number of anti-Tac binding sites ranged from 4,300 to 11,400 in fresh cells and from 6,100 to 96,000/cell in short term cultured leukemic cells, whereas phytohemagglutinin-P(PHA-P)-stimulated normal T cells exhibited 7,000 to 35,000 anti-Tac binding sites/cell. HTLV-I-infected cell lines such as MT-1 and HUT-102 expressed a markedly enhanced number of Tac Ag molecules. Leukemic cells from 15 ATL patients showed no or very poor proliferative response to various concentrations of IL-2, although they expressed Tac Ag. Radiolabeled IL-2 binding experiments revealed that ATL leukemic cells could bind IL-2 although the number of IL-2 binding sites was much less than that of anti-Tac binding sites. IL-2 receptors on ATL cells, unlike normal activated T cells, were not modulated (down-regulated) by anti-Tac antibody.(ABSTRACT TRUNCATED AT 250 WORDS)

A case of 17 alpha-hydroxylase deficiency syndrome associated with right adrenal tumor.

A 35-year-old woman, who had been hypertensive for about 17 years and had lacked menarche, showed hypokalemia, low plasma cortisol and aldosterone levels, suppressed renin activity, and marked elevation of plasma corticosterone. The patient was diagnosed as having 17 alpha-hydroxylase deficiency from functional studies. In addition, a right adrenal tumor was found by adrenal venography. Adrenal venous sampling showed that this tumor might be secreting corticosterone and possibly also deoxycorticosterone (DOC). The genotype was 46,XY, so she was diagnosed as having male pseudohermaphroditism. Right adrenalectomy and contralateral adrenal biopsy were done. The retained testicles were removed. Dexamethasone administration normalized the blood pressure and serum potassium. This is the first report of 17 alpha-hydroxylase deficiency with a right adrenal tumor.