IL-2/CD25 axis mediates cellular networks promoting the growth of CD25+ acute myeloid leukemia cells.

Although the expression of interleukin-2 receptor α-chain (IL-2Rα, CD25) has been provided prognostic significance independent of known biomarkers in acute myeloid leukemia (AML), the functional role of CD25 molecule remains unknown. Since IL-2 can be trans-presented via CD25 to another cell, CD25+AML cells may deliver environmental IL-2 to surrounding immune cells to produce myeloid growth factors for their proliferation. We hypothesize that cellular interactions via IL-2/CD25 axis in the bone marrow microenvironment contributes to the growth advantage of these AML cells and affects the clinical outcome of those AML patients.

IL-2/IL-3 interplay mediates growth of CD25 positive acute myeloid leukemia cells.

Cell surface interleukin-2 receptor α-chain (IL-2Rα, CD25) expression is currently recognized to be a strong predictor for poor prognosis in patients with acute myeloid leukemia (AML). However, it is still unknown that the reason why CD25 positive AML patients have a dismal clinical outcome. CD25 positive AML cells are generally unresponsive to IL-2, but strongly respond to IL-3. The levels of IL-3Rα on these AML cells are very high and directly proportional to the CD25 levels. T-lymphocytes produce IL-3 in response to stimuli including IL-2-mediated activation. Thus, CD25 on AML cells may capture environmental IL-2 and deliver it to the surrounding T-lymphocytes expressing IL-2Rß/γc, leading to the production of IL-3 as a growth stimulus to CD25 positive AML cells. We hypothesize that IL-2/IL-3 interplay via CD25 is responsible for the growth property of CD25 positive AML, which may affect clinical behavior of those patients.

Prognostic Relevance of Cytokine Receptor Expression in Acute Myeloid Leukemia: Interleukin-2 Receptor α-Chain (CD25) Expression Predicts a Poor Prognosis.

A variety of cytokine/cytokine receptor systems affect the biological behavior of acute leukemia cells. However, little is known about the clinical relevance of cytokine receptor expression in acute myeloid leukemia (AML). We quantitatively examined the expression of interleukin-2 receptor α-chain (IL-2Rα, also known as CD25), IL-2Rß, IL-3Rα, IL-4Rα, IL-5Rα, IL-6Rα, IL-7Rα, the common ß-chain (ßc), γc, granulocyte-macrophage colony-stimulating factor (GM-CSF)Rα, G-CSFR, c-fms, c-mpl, c-kit, FLT3, and GP130 in leukemia cells from 767 adult patients with AML by flow cytometry and determined their prevalence and clinical significance. All cytokine receptors examined were expressed at varying levels, whereas the levels of IL-3Rα, GM-CSFRα, IL-2Rα, γc, c-kit, and G-CSFR exhibited a wide spectrum of ≥10,000 sites/cell. In terms of their French-American-British classification types, GM-CSFRα and c-fms were preferentially expressed in M4/M5 patients, G-CSF in M3 patients, and IL-2Rα in non-M3 patients. Elevated levels of IL-3Rα, GM-CSFRα, and IL-2Rα correlated with leukocytosis. In patients ≤60 years old, higher levels of these 3 receptors correlated with poor responses to conventional chemotherapy, but only IL-2Rα was associated with a shorter overall survival. By incorporating IL-2Rα status into cytogenetic risk stratification, we could sort out a significantly adverse-risk cohort from the cytogenetically intermediate-risk group. Analyses with various phenotypical risk markers revealed the expression of IL-2Rα as an independent prognostic indicator in patients with intermediate-risk cytogenetics. These findings were not observed in patients >60 years old. Our results indicate that several cytokine receptors were associated with certain cellular and clinical features, but IL-2Rα alone had prognostic value that provides an additional marker to improve current risk evaluation in AML patients ≤60 years old.

[A case of gastric cancer accompanied by disseminated carcinomatosis of bone marrow wherein long-term chemotherapy was enabled by early supportive palliative care].

Here we report gastric cancer accompanied by bone marrow carcinomatosis in a patient for whom long-term chemotherapy was enabled by early pain-relief therapy. A 45-year-old man was admitted to our hospital because of back pain associated with multiple spinal tumors in June 2011. Blood tests showed a trend toward disseminated intravascular coagulation(DIC) and gastric cancer was suspected as the primary lesion. Because pain was severe, emergency pain relief was provided by flurbiprofen axetil and a continuous subcutaneous infusion of fentanyl citrate. After bone marrow examination gave a diagnosis of poorly differentiated adenocarcinoma, we performed sequential methotrexate(MTX)and 5-fluorouracil(5-FU)therapy. The therapy successfully decreased tumor marker levels, and alkaline phosphatase and lactate dehydrogenase levels normalized. Finally, gastric cancer accompanied by bone marrow carcinomatosis was diagnosed. Because the patient had anxiety and spiritual pain from the time of admission, psychiatric care was also required. In November 2011, the tumor recurred, and we switched therapy to a combination of S-1 and cisplatin. The patient's pain was controlled by combined treatment with a fentanyl patch and etodolac, and he was discharged in December 2011. However, severe pain recurred and pain therapy was continued. DIC developed in February 2012 and transiently resolved after resuming combination therapy with MTX and 5-FU; however, it subsequently recurred, leading to the patient's death in May 2012.

[Palliative care for patients with hematological malignancies in the Japan Baptist Medical Foundation].

The Japan Baptist Medical Foundation has established a "hospice triangle" system consisting of the hospice ward, general ward, and home hospice. Palliative care is provided for patients with various types of cancer, including hematological malignancies, in the place where they desire to receive care. From December 2010 to December 2013, 37 patients with hematological malignancies received palliative care and died at our foundation. Eleven (30%) patients died in the hospice ward, 24 (65%) in the general ward, and 2 (5%) at home. The median interval between the final dose of chemotherapy and death was 12 (1- 88) days. Twenty (54%) patients received transfusions during the last 2 weeks prior to death. Quick response to patient situations and early introduction of palliative care are essential to support end-of-life decision-making processes, because the clinical course of hematological malignancies generally differs from that of other cancers.

Double-hit lymphoma with a feature of follicular lymphoma concurrent with clonally related B lymphoblastic leukemia : a preference of transformation for the bone marrow.

We describe a 65-year-old woman with follicular lymphoma (FL), grade 1, stage IV, which occurred concurrently with B lymphoblastic leukemia/lymphoma. Through the evaluation of FL, the cells that were morphologically suspected of having undergone transformation were found in the bone marrow, and flow cytometric and cytogenetic analyses detected the transformed population that suggested concomitant t(8;22) with typical t(14;18) FL cells. Repeated analyses of the lymph nodes demonstrated the typical morphological, phenotypic, and cytogenetic features of FL. The patient received several multiagent chemotherapy regimens, but the disease gradually became resistant, and the patient died of leukemic progression. In B-cell malignancies, cases involving both BCL2 and MYC translocations simultaneously, so-called "double-hit leukemia/lymphoma (DHL)", have occasionally been reported. Patients with this type of translocation have a very poor clinical outcome, and no standard therapy has been established. In our case, FL was supposed to have transformed into B lymphoblastic leukemia via Burkitt's lymphoma-like phase. Our case is unique in that the transformed DHL cells, derived from clonally related FL cells, showed ongoing transformation from Burkitt-like feature to B lymphoblastic leukemia exclusively in the bone marrow, which suggests that the bone marrow may provide a preferable milieu for malignant transformation. Similar cases should be accumulated and analyzed carefully.

High serum levels of soluble interleukin-2 receptor in acute myeloid leukemia: correlation with poor prognosis and CD4 expression on blast cells.

BACKGORUND: Although increased serum levels of soluble interleukin-2 receptor (sIL-2R) and their clinical importance are well known in mature type lymphoproliferative disorders (LD), little data is available about such information in acute type hematological malignancies. METHODS: We examined the serum levels of sIL-2R in 57 adult patients with acute type leukemias: 32 with acute myeloid leukemia (AML), 14 acute lymphoblastic leukemia (ALL) and 11 chronic myelocytic leukemia in blast crisis (CMLBC), and in 29 adult patients with mature type LD, and assessed their cellular and clinical relevance in acute type leukemias. RESULTS: No significant differences were seen in the sIL-2R levels between acute type leukemias and mature type LD. In AML, serum sIL-2R levels were related to the cell surface CD4 expression on blast cells, and patients with higher levels ≧2000U/ml had a poorer prognosis (lower response to chemotherapy and shorter overall survival). CONCLUSIONS: These results suggest that serum sIL-2R level elevates in acute type leukemias like mature type LD, and increased sIL-2R levels in adult AML are correlated with certain biological and clinical characteristics.

Clinicopathologic significance of loss of CD19 expression in diffuse large B-cell lymphoma.

To clarify the clinicopathologic significance of a loss of CD19 expression in diffuse large B-cell lymphoma (DLBCL), we evaluated CD19 expression immunohistochemically in frozen sections from 227 patients who had received diagnoses of DLBCL according to the World Health Organization classification between 1987 and 2002. Histopathologic features of patients with CD19- DLBCL were reviewed, and their clinical features, immunophenotypes, and prognoses were compared retrospectively with respect to CD19 expression. CD19 expression was positive in 205 patients (90%). The 22 patients with CD19- DLBCL had a median age of 63 years, and the male-female ratio was 11:11. Compared with patients with CD19+ DLBCL, those with CD19- DLBCL more frequently showed elevated lactate dehydrogenase (LDH) levels (73%, P= .011). Morphologically, 15 (79%) of the 19 CD19- DLBCL patients examined showed plasmablastic/plasmacytoid differentiation. Patients with CD19- DLBCL expressed BCL2 protein less frequently than CD19+ DLBCL (P= .042). Especially noteworthy is that half of the patients with CD19- DLBCL died within 2 years after diagnosis. The CD19- DLBCL group showed a survival curve significantly inferior to that for the CD19+ group (P= .034, generalized Wilcoxon test). Our findings demonstrate that loss of CD19 expression in DLBCL is associated with elevated serum LDH levels and a poor prognosis, especially during the early follow-up period.

Low p53 expression of acute myelocytic leukemia cells with t(8;21) chromosome abnormality: association with low p14(ARF) expression.

In this study, the mRNA expression of p14(ARF) in t(8;21)AML cells was found to be significantly lower than acute myelocytic leukemia (AML) cells without t(8;21) chromosome abnormality, which was concordant with previous observation by Linggi et al. that AML1-MTG8 represses the transcription of p14(ARF). Although p53 mRNA expression level of t(8;21)AML cells was not low, p53 protein expression was reduced in t(8;21)AML cells. Genotoxic damage by ionizing radiation did not induce p53 upregulation in t(8;21)AML cells. Since p14(ARF) has been demonstrated to inhibit p53 degradation by binding to MDM2, repression of p14(ARF) expression in t(8;21)AML may facilitate the degradation of p53 by MDM2. Low p14(ARF) in t(8;21)AML may also account for the absence of upregulation of p53 by ionizing radiation. Then, we have shown that p53 expression level was inversely correlated with S/G2/M population of cell cycle in AML cells. Most of the t(8;21)AML are considered to be in p53(low) S/G2/M(high). It is now widely known that formation of AML1-MTG8 by t(8;21) translocation is a very early event in leukemogenesis, and AML1-MTG8 alone might have limited proliferative potential. Then, secondary oncogenic events such as activated receptor tyrosine kinase (like c-kit mutation), is necessary to become full-blown leukemia. Low p53 protein expression and insufficient induction of p53 by genotoxic damage might increase the opportunity to obtain additional oncogenic events, since genome guard function of p53 does not work in t(8;21)AML cells.

CD21S antigen expression in tumour cells of diffuse large B-cell lymphomas is an independent prognostic factor indicating better overall survival.

To evaluate the clinical significance of CD21S expression of diffuse large B-cell lymphoma (DLBCL) tumour cells, we compared their clinical features, immunophenotype, response to therapy and outcome in relation to CD21S expression. Between 1987 and 1999, frozen sections from 240 DLBCL cases were examined for CD21S expression by immunohistochemical methods. CD21S expression was detected on the tumour cells of 87 (36%) cases. The median age of the CD21S(+) DLBCL cases was 65 years (range: 17-84 years), the male-female ratio was 42:45, and they showed the following clinical features: Eastern Cooperative Oncology Group score >1 in 14%, lactate dehydrogenase greater than normal levels in 38%, extranodal sites >1 in 14%, stages III/IV disease at diagnosis in 29%, B symptoms in 17%, and a high/high-intermediate International Prognostic Index (IPI) in 23%. They also showed a better overall survival (P = 0.00001, log-rank test) and a better complete remission rate (P = 0.00004, chi-square test) than CD21S(-) DLBCL. Moreover, CD21S(+) DLBCL showed a better survival than CD21S(-) DLBCL for both low/low-intermediate and high/high-intermediate risk categories of IPI (P = 0.045 and P = 0.0016 respectively). Multivariate analysis identified CD21S expression as an independent factor for survival when compared with the five IPI factors. These findings indicate that CD21S expression of DLBCL tumour cells is a useful prognostic factor for survival.

Augmented expression of P-gp/multi-drug resistance gene by all-trans retinoic acid in monocytic leukemic cells.

P-glycoprotein (P-gp)/multi-drug resistance 1 (MDR1) gene is recognized to be, at least in part, responsible for the refractoriness to chemotherapy of leukemia. The transcriptional mechanism of MDR1 gene is largely unknown. However, recent reports have clarified that early growth response 1 gene (Egr1) positively regulates MDR1 transcription, while Wilms' tumor suppressor gene (WT1) does negative regulation of MDR1 gene expression in 12-O-tetradecanoylphorbol-13-acetate treated K562 cells. In addition, Egr1 and WT1 are structurally related transcription factors and bind to quite similar DNA sequences. Our study of mRNA expression profile of Egr1, WT1 and MDR1 in fresh AML samples demonstrated that there are disease-specific patterns. Egr1 mRNA was frequently and strongly expressed in monocytic leukemia cells, especially in AML M4 cells. WT1 mRNA was undetectable in t(8;21) AML cells. mRNA expression of MDR1 was frequent in AML M1 and t(8;21) AML cells, in which the expression level was highest in AML M1 and was low in monocytic leukemia (M4 and M5). Then, expression level of MDR1 was inversely correlated with Egr1. By liquid culture of leukemia cell lines and fresh AML cells with the addition of all-trans retinoic acid (ATRA), modulation of P-gp/MDR1 and Egr1 was observed and the pattern of modulation was divided into four groups: (1) blastic AML type, in which distinct expression of P-gp/MDR1 and CD34 was not influenced by ATRA; (2) t(8;21)AML type, in which P-gp/MDR1 expression was augmented by ATRA, while CD34 was kept high; (3) AML M3 type, in which P-gp/MDR1 expression was reduced with granulocytic differentiation by ATRA; (4) monocytic AML type, in which P-gp/MDR1 expression was augmented by ATRA, while CD34 expression decreased, and strong Egr1 expression was downregulated just prior to the augmentation of P-gp/MDR1 expression. WT1 expression was not influenced by the addition of ATRA in each group. Previous reports have suggested that P-gp/MDR1 plays an important role in resistance to chemotherapy, and is recognized as one of the stem cell marker. However, P-gp/MDR1 expression augmented by ATRA, which was observed in monocytic AML, was recognized as a functional molecule of mature monocyte/macrophage, because CD34 expression decreased and CD13 expression increased by ATRA. Finally, expression of P-gp/MDR1 in monocytic leukemia, which was functionally confirmed by Rh123 efflux study, was thought to be closely related to the characteristic modulation of Egr1 expression by ATRA.