Nobuhiro Kanemura

Synergistic effects of RXRα and PPARγ ligands to inhibit growth in human colon cancer cells—phosphorylated RXRα is a critical target for colon cancer management

Background and aims: The activation of the peroxisome proliferator-activated receptor &ggr; (PPAR&ggr;) that forms heterodimers with retinoid X receptors (RXRs) elicits an antineoplastic effect on colorectal cancer. It was previously reported that the accumulation of the non-functional phosphorylated form of RXR&agr; (p-RXR&agr;) interfered with its signalling and promoted the growth of hepatoma cells. In this study the effects of p-RXR&agr; on the ability of RXR&agr; and PPAR&ggr; ligands to inhibit growth in colon cancer cells was examined. Methods: The effects of the combination of the PPAR&ggr; ligand ciglitazone and the RXR&agr; lignad 9-cis-retinoic acid (RA) on inhibition of cell growth in Caco2 human colon cancer cells which express high levels of p-RXR&agr; protein were examined Results: The RXR&agr; protein was phospholylated and also accumulated in human colon cancer tissue samples as well as human colon cancer cell lines. When the phosphorylation of RXR&agr; was inhibited by the MEK inhibitor PD98059 or by transfection with a point-mutated RXR&agr;, which mimicked the unphosphorylated form, the combination of 9-cisRA and ciglitazone synergistically inhibited the cell growth and induced apoptosis. The combined treatment with these agents also caused a decrease in the expression levels of both cyclo-oxygenase-2 (COX-2) and c-Jun proteins and mRNAs. Reporter assays indicated that this combination induced the transcriptional activity of the peroxisome proliferator-responsive element promoter and also inhibited that of the AP-1 promoter. Conclusion: A malfunction of RXR&agr; due to phosphorylation is associated with colorectal cancer. Therefore, the inhibition of phosphorylation of RXR&agr; and the activation of the RXR–PPAR&ggr; heterodimer by their respective ligands may be useful in the chemoprevention and/or treatment of colorectal cancer.

Endoscopic Ultrasound-Guided Fine Needle Aspiration Biopsy for Diagnosis of Lymphoproliferative Disorders: Feasibility of Immunohistological, Flow Cytometric, and Cytogenetic Assessments

OBJECTIVES:In addition to morphology, immunophenotype and genetic abnormalities should be assessed during diagnosis and subclassification of lymphoproliferative disorders. The objective of this study was to evaluate the yield of endoscopic ultrasound-guided fine needle aspiration biopsy (EUS-FNAB) using a standard 19-gauge needle for diagnosis and subclassification of lymphoma, assessing the feasibility of immunohistological, flow cytometric, and cytogenetic assessments.METHODS:Two hundred forty patients with suspected lymphoma were referred for EUS-FNAB to our quaternary EUS center between June 2005 and December 2010. EUS-FNAB using a conventional 19-gauge needle was attempted for all patients, followed by histological assessments including immunohistological staining, flow cytometry, and cytogenetic analysis (G-band karyotyping). Among the patients, 152 were ultimately diagnosed with lymphoma. The primary outcome measure of this study was the sensitivity of histological assessment, including immunohistological staining, flow cytometry, and G-band karyotyping, for diagnosis and subclassification of lymphoma.RESULTS:Among the 152 patients ultimately diagnosed with lymphoma, 147 patients (96.7%) were diagnosed by EUS-FNAB, and classification in accordance with the WHO (World Health Organization) system was also possible for 135 patients (88.8%) on the basis of histological findings, including immunohistological staining. Flow cytometry showed abnormal or unusual cell populations in 121 (79.6%) of the 152 patients diagnosed with lymphoma, and in 114 (90.5%) of the 126 patients diagnosed with B-cell lymphoma. Specific cytogenetic abnormalities were detected in 21 (13.8%) of the lymphoma patients.CONCLUSIONS:EUS-FNAB using a standard 19-gauge needle has high diagnostic value for lymphoma. Immunophenotyping is usually possible, while cytogenetic abnormalities can be identified in a relatively limited number of patients.

Serum concentration of L-kynurenine predicts the clinical outcome of patients with diffuse large B-cell lymphoma treated with R-CHOP

Purpose: Introduction of rituximab has largely improved the prognosis of patients with diffuse large B‐cell lymphoma(DLBCL). Such change in therapeutic outcome necessitates the identification of additional prognostic factors to conventional indexes that have been validated for CHOP without rituximab. Indoleamine 2,3‐dioxygenase (IDO) exerts intense immunomodulatory effects because of enzymatic activities that catalyze the breakdown of the essential amino acid L‐tryptophan. The activity of IDO can be estimated by measuring the serum concentration of L‐kynurenine. Here, we investigated the role of L‐kynurenine as a prognostic marker in R‐CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisolone) therapy. Experimental design: Data from 73 consecutive patients treated with eight cycles of R‐CHOP or R‐THP (tetrahydropyranyl adriamycin)‐COP between December 2002 and March 2007 were analyzed. L‐kynurenine concentrations in serum samples obtained at admission were measured by high‐performance liquid chromatography. Results: The median serum L‐kynurenine level was 1.575 μm (range 0.537–9.588). The complete response (CR) rates of patients with L‐kynurenine <1.5 and ≥1.5 μm were 83% and 61%, respectively (P < 0.05). The three‐yr overall survival (OS) rates for patients with L‐kynurenine <1.5 and ≥1.5 μm were 89% and 58%, respectively (P < 0.005). In addition, higher age, poor performance status, elevated serum lactate dehydrogenase, and unfavorable as well as revised International Prognosis Index were significantly worse factors for CR rate and OS. Multivariate analyses revealed only L‐kynurenine as an independent prognostic factor for OS. Conclusions: Serum L‐kynurenine might be a novel prognostic factor to determine the treatment outcome of DLBCL with the R‐CHOP regimen.

Indoleamine 2,3-dioxygenase in tumor tissue indicates prognosis in patients with diffuse large B-cell lymphoma treated with R-CHOP

Indoleamine 2,3-dioxygenase (IDO) exerts immunomodulatory effects due to enzymatic activities catalyzing the essential amino acid l-tryptophan. IDO activity might play an important role in regulating immune responses exerted by antigen-presenting cells as a potent tool to help escape from assault by the immune system. In this study, we performed immunohistochemical analysis for IDO expression using mouse anti-human IDO monoclonal antibody in 119 tissue samples of diffuse large B-cell lymphoma (DLBCL) obtained before treatment with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). Not only the lymphoma cells themselves but also dendritic cells (DCs) expressed IDO. Positive IDO expression in lymphoma cells was found in 38 cases (32%). Complete remission rates in patients with IDO-positive DLBCL and IDO-negative DLBCL were 55.3% and 79.0% (p = 0.008), while 3-year overall survival rates were 49.8% and 78.8%, respectively (p = 0.0003). IDO activity might thus play an important role in DLBCL and cells that express IDO appear important for determining outcomes after R-CHOP treatment. IDO might represent a candidate therapeutic target for DLBCL patients who show resistance to chemotherapy.

Intrahepatic cholangiocarcinoma arising 10 years after the excision of congenital extrahepatic biliary dilation

A 52-year-old woman was found to have a liver tumor during treatment for a liver abscess. The tumor was diagnosed as intrahepatic cholangiocarcinoma by closer examinations, including a percutaneous needle biopsy. Ten years previously, she had undergone excision of a choledochal cyst, with reconstruction by Roux-en-Y hepaticojejunostomy, as treatment for Todanis type Ia congenital biliary dilation, which had been confined only to the extrahepatic bile duct. The significant association between congenital biliary dilation and hepatobiliary malignancies is well known. Some patients have been reported to develop biliary cancer long after the excision of the entire extrahepatic bile duct and hepaticoenterostomy. However, in these patients, the development mostly took place in the remnant choledochal cyst, the anastomotic site, or in the dilated intrahepatic bile duct of Todanis type IV-A congenital biliary dilation. The development of intrahepatic cholangiocarcinoma after operation has not been reported previously in a patient with Todanis type I congenital biliary dilation. This case suggests that the entire biliary tree may have a high risk of field cancerization, even in extrahepatic congenital biliary dilation.

Late-onset neutropenia in patients treated with rituximab for non-Hodgkin's lymphoma.

Late-onset grade 4 neutropenia occurred in 3 (5.6%) of 54 non-Hodgkin’s lymphoma patients treated with rituximab between September 2001 and March 2004. Neutropenia appeared 5 to 25 weeks after administration of cytotoxic agents in combination with rituximab and recurred 4 and 17 weeks after the first onset in 2 patients. Five episodes occurred in a total of 332 cycles of rituximab therapy. Bone marrow findings at the time of late-onset neutropenia showed neutrophil matura-tion arrest with or without reversible myeloid dysplasia in 3 episodes and selective depletion of the myeloid series in 1 episode. Neither circulating immune complexes nor antineutrophil antibodies were detected during the 3 episodes that we evaluated. Bone marrow cells stained CD8- and CD57-. Late-onset neutropenia resolved 5 to 7 days after granulocyte colony-stimulating factor therapy was started. Further studies are needed to determine how rituximab functions and to identify appropriate countermeasures.

A prospective study of P‐IMVP‐16/CBDCA: a novel salvage chemotherapy for patients with aggressive non‐Hodgkin's lymphoma who had previously received CHOP therapy as first‐line chemotherapy

Abstract:  The purpose of this study was to determine the efficacy of salvage chemotherapy with, P‐IMVP‐16/CBDCA, consisting of carboplatin (CBDCA), etoposide (VP‐16), ifosfamide (IFM), and methotrexate (MTX), for patients with aggressive non‐Hodgkins lymphoma (NHL) who had previously received CHOP [a regimen of cyclophosphamide, hydroxydaunomycin, Oncovin (vincristine), and prednisolone], as first‐line chemotherapy. The 45 consecutively enrolled patients received methylprednisolone (mPSL) 1000 mg per body for 3 d (from day 1 to day 3), IFM 1000 mg/m2 for 5 d (from day 1 to day 5), MTX 30 mg/m2 on day 3 and day 10, VP‐16 80 mg/m2 for 3 d (from day 1 to day 3), and CBDCA 300 mg/m2 on day 1, with granulocyte colony‐stimulating factor every 21 d. Patients 70 yr of age or older were given 75% of the standard dose. The response rate [complete response (CR) plus partial response (PR)] was 55.6% (25/45), including 12 (26.7%) CR and 13 (28.9%) PR. The overall survival rate for the 45 patients was 31.1% at 1 yr and 17.3% at 2 yr. The failure‐free survival rate for the 45 patients was 6.7% at 1 yr and 4.4% at 2 yr. The survival rate for the 25 responders was 48.0% at 1 yr and 24.0% at 2 yr, and the survival rate for the 20 non‐responders was 10.0% at 1 yr (P<0.001). Multivariate analysis demonstrated that prior chemotherapy (reduced‐dose CHOP for age 70 yr or older) and the number of cases of extranodal involvement (>1) were significant unfavorable factors for overall survival. Although the major toxicity was neutropenia, no patient died of infection related to neutropenia. Non‐hematological adverse effects were predominantly mild and tolerable. Unfortunately, the clinical outcome with P‐IMVP‐16/CBDCA was unfavorable, possibly because the study comprised consecutive patients who had received identified intensive chemotherapy, such as biweekly CHOP. Salvage chemotherapy with P‐IMVP‐16/CBDCA is not sufficient to cure relapsed or refractory aggressive NHL. Aggressive NHL should be cured by first‐line chemotherapy with or without hematopoietic stem cell transplantation.

Serum‐soluble tumor necrosis factor receptor 2 (sTNF‐R2) level determines clinical outcome in patients with aggressive non‐Hodgkin's lymphoma

Abstract:  Background: Recently investigators have worked to identify prognostic factors in non‐Hodgkins lymphoma (NHL) so an appropriate therapeutic plan can be put in action. The aim of the present study was to assess the prognostic significance of serum soluble tumor necrosis factor receptor (sTNF‐R) 2 in aggressive NHL. Methods: One hundred and ten consecutive patients with aggressive NHL who were previously untreated (diffuse large B‐cell lymphoma; 94, peripheral T‐cell lymphoma; 16) were prospectively enrolled in this study between 1997 and 2002. The patients were treated with 6–8 cycles of CHOP or THP‐COP regimens. Results: High serum sTNF‐Rs level was associated with some poor prognostic factors and low complete remission rate. Patients with high sTNF‐R1 (4 ng/mL and over) and sTNF‐R2 (15 ng/mL and over) at onset had significantly lower survival rates (5 yr: 19%, 19%) than those with low sTNF‐R1 (under 4 ng/mL) and sTNF‐R2 (under 15 ng/mL) (62% and 69%), respectively (P < 0.0005 and 0.0001). Multivariate analysis employing sTNF‐R2 and some conventional prognostic factors demonstrated that a combination of sTNF‐R2 and performance status, and that of sTNF‐R2, sIL‐2R, and LDH were significant prognostic factors for poor overall survival and for poor event‐free survival, respectively. In addition, we attempted to use sTNF‐R2 in combination with the international prognostic index (IPI). The patients in the high risk group and those with high sTNF‐R2 in the low‐intermediate (LI)/high‐intermediate (HI) risk group had significantly lower survival rates than the patients in the low risk group and those with low sTNF‐R2 in LI/HI risk group (P < 0.0001). Conclusions: The results suggest that a high serum sTNF‐R2 level predicts a poor prognosis in aggressive NHL and may be a useful biomarker for selecting appropriate treatment when used in combination with the IPI.

Efficacy and safety of micafungin for treating febrile neutropenia in hematological malignancies

Less toxic antifungal drugs are required for empirical antifungal therapy. Micafungin is an echinocandin drug that is effective against both Candida and Aspergillus, and preliminary clinical studies have shown good antifungal activity. We prospectively examined the effect and safety of micafungin against febrile neutropenia with suspected fungal infection in 53 patients (median age, 56 years) who had undergone chemotherapy. The administered dose of micafungin was 150 mg/day, and its effect was evaluated as fever resolution as well as the results of chest imaging and serum fungal tests. Micafungin levels were measured on day 4 after the first administration using high‐performance liquid chromatography. We also measured trough levels of micafungin. Underlying diseases comprised acute lymphoblastic leukemia (n = 4), acute myeloid leukemia (n = 20), multiple myeloma (n = 3), and non‐Hodgkins lymphoma (n = 26). The overall efficacy of micafungin was 70%. Breakthrough fungal infections were documented in two (3.8%) patients, both of whom died of invasive mycosis. None of the patients were switched to other antifungal drugs due to events unrelated to adverse effects. Plasma levels of micafungin and the degree of hepatic or renal dysfunction did not correlate. Micafungin is safe and effective for the empirical antifungal therapy of febrile neutropenia in patients with hematological malignancies. Am. J. Hematol., 2010.

Phase II study of the tetrahydropyranyl adriamycin–cyclophosphamide, vincristine, and prednisolone regimen combined with rituximab as first-line treatment for elderly patients with diffuse large B-cell lymphoma

The anthracycline drug pirarubicin (tetrahydropyranyl adriamycin; THP) apparently has fewer cardiotoxic effects than doxorubicin. We previously described the benefit of the THP-COP regimen comprising cyclophosphamide, THP, vincristine, and prednisolone for elderly patients with diffuse large B-cell lymphoma (DLBCL). However, that study was completed before rituximab (R) was introduced into clinical practice. Here we report a phase II study of the THP-COP regimen combined with R (R-THP-COP) every 3 weeks. The complete response and 3-year overall survival rates was 63% and 53%, respectively, and no deaths were related to the regimen. We conclude that the R-THP-COP regimen is safe and effective for patients with DLBCL. Based on these results, a randomized controlled trial of rituximab–cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP) and R-THP-COP as a phase III study is ongoing.