Jee Sook Hahn

Angiocentric Lymphoma of the Head and Neck: Patterns of Systemic Failure After Radiation Treatment

PURPOSE To investigate the patterns of systemic failure and the clinical outcome in patients with angiocentric lymphoma of the head and neck who were treated with radiation alone, and to discuss the optimal mode of treatment for these patients. PATIENTS AND METHODS We reviewed the records of 92 patients with stage I or II angiocentric lymphoma who were treated at Yonsei Cancer Center between 1976 and 1994. All patients were treated with involved-field irradiation. Radiation doses ranged from 40 to 60 Gy (median dose, 50.4 Gy). Treatment response, patterns of treatment failure including systemic failure, and clinical outcome after radiation treatment were analyzed. RESULTS The most frequently involved site was the nasal cavity, either alone or in conjunction with other sites. In 16 patients (17.4%), angiocentric lymphoma was accompanied by cervical lymphadenopathy. Disease was classified as stage I in 62 patients (67.4%) and stage II in 30 patients (32.6%). After completion of radiation treatment, 61 patients (66.3%) achieved a complete response and 16 (17.4%) a partial response. Half of the patients (50.0%) ultimately experienced local recurrence with or without other components of failure, whereas regional failure was relatively uncommon (10.9%). Systemic failure occurred in 25.0% of patients during follow-up. Six patients had histologic findings identical to those at the time of the original disease (group I), whereas four patients exhibited morphologic features of frank lymphomas (group II). The majority of patients with systemic relapse had the predilection sites for widespread extranodal involvement, such as the skin, brain, lung, gastrointestinal tract, or testes. In addition, seven patients died from various medical illnesses or immunologic disorders, including hemophagocytic syndrome and second primary cancers (group III). After a median follow-up of 56 months, the overall survival and disease-free survival rates for all patients were 40.1% and 37.8%, respectively. All patients except one with systemic failure died within 1 year. CONCLUSION Treatment with radiation alone had suboptimal results, partly because of the occurrence of a variety of systemic failure with diverse clinicopathologic features. Given the frequent occurrence of systemic failure after radiation treatment, we believe that the multimodality treatment approach containing more effective chemotherapeutic agents should be incorporated in the treatment of angiocentric lymphoma confined to the head and neck.

Constitutive phosphorylation of Akt/PKB protein in acute myeloid leukemia: its significance as a prognostic variable.

Constitutive phosphorylation of Akt/PKB protein in acute myeloid leukemia: its significance as a prognostic variable

Treatment of high-risk acute myelogenous leukaemia by myeloablative chemoradiotherapy followed by co-infusion of T cell-depleted haematopoietic stem cells and culture-expanded marrow mesenchymal stem cells from a related donor with one fully mismatched human leucocyte antigen haplotype

Summary.  A 20‐year‐old woman with high‐risk acute myelogenous leukaemia was transplanted with granulocyte colony stimulating factor (G‐CSF)‐mobilized peripheral blood CD34+ haematopoietic stem cells and bone‐marrow‐derived mesenchymal stem cells (MSC) from her human leucocyte antigen haplotype‐mismatched father after myeloablative conditioning therapy. The patient engrafted rapidly and had no acute or chronic graft‐versus‐host disease. Since transplantation, the patient has shown an enduring trilineage haematological complete response without any evidence of leukaemia relapse at 31 months. We suggest that MSC can be used effectively for genetically haploidentical haematopoietic stem cell transplantation for acute leukaemia.

Cytoplasmic Mislocalization of p27Kip1 Protein Is Associated with Constitutive Phosphorylation of Akt or Protein Kinase B and Poor Prognosis in Acute Myelogenous Leukemia

Cyclin-dependent kinase inhibitor p27Kip1 functions at the nuclear level by binding to cyclin E/cyclin-dependent kinase-2. It was shown that Akt or protein kinase B (Akt/PKB)-dependent phosphorylation of p27Kip1 led to the cytoplasmic mislocalization of p27Kip1, suggesting the potential abrogation of its activity. Here, we evaluated the localization of p27Kip1 protein in leukemic blasts in relation to Akt/PKB phosphorylation and clinical outcomes in acute myelogenous leukemia (AML). Western blot analysis of the nuclear and cytoplasmic fractions revealed a heterogenous localization pattern of p27Kip1 in AML. Cytoplasmic mislocalization of p27Kip1 was significantly associated with the constitutive serine473 Akt/PKB phosphorylation in AML cells (P < 0.05). Transfection of U937 cells with an expression construct encoding the constitutively active form of Akt/PKB resulted in a remarkable increase in the levels of cytoplasmic p27Kip1. Whereas the transfection of U937 cells with a construct encoding dominant-negative Akt/PKB resulted in a recovery of nuclear localization of p27Kip1. Both the disease-free survival and overall survival are significantly shorter in AML cases with high cytoplasmic to nuclear ratio of p27Kip1 localization compared with the cases with low cytoplasmic to nuclear ratio (P = 0.0353, P = 0.0023, respectively). Multivariate analysis indicated that the cytoplasmic to nuclear ratio of p27Kip1 localization was an independent prognostic variable for both disease-free survival and overall survival (P = 0.043, P = 0.008, respectively). These findings additionally extend our understanding of the role of p27Kip1 in AML, and buttress the case of p27Kip1 mislocalization as a prognostic indicator and Akt/PKB/p27Kip1 pathway as a ready target for antileukemia therapy.

Phosphatase and tensin homologue phosphorylation in the C-terminal regulatory domain is frequently observed in acute myeloid leukaemia and associated with poor clinical outcome

Summary. Phosphorylation of PTEN (phosphatase and tensin homologue) affects PTEN protein stability and function. In this study, phosphorylated PTEN (pPTEN) was observed in 45 (73·8%) of 61 cases with acute myeloid leukaemia (AML). Phosphorylation of Akt and its downstream molecules [FKHR; Forkhead (Drosophila) homologue 1; and GSK‐3β; glycogen synthase kinase 3 beta] was significantly associated with pPTEN (P < 0·001). The complete remission rates were not different with respect to pPTEN, but overall survival was significantly shorter in patients with pPTEN (P < 0·05). Constitutive PTEN phosphorylation may add insight into the molecular pathogenesis of AML, and may be a new parameter for an unfavourable outcome.

Expression of Fas antigen in acute myeloid leukaemia is associated with therapeutic response to chemotherapy

Flow cytometric immunofluorescent analysis was used to assess Fas antigen (CD95) expression in blasts obtained from the bone marrow of 30 patients with acute myeloid leukaemia. The percentage of positive cells in each sample was highly variable. Fas antigen expression did not correlate with age, FAB subtype, white blood cell counts, or CD34 expression. Low expression of Fas was associated with a low complete remission rate after induction chemotherapy (62.5% in cases with <20% positive cells v 92.9% in cases with ≥ 20% positive cells, P<0.01). The main cause for not achieving remission was resistant disease. Our results suggest that the quantitation of Fas expression can be predictive of treatment outcome in acute myeloid leukaemia.

Clinical relevance of three subtypes of primary sinonasal lymphoma characterized by immunophenotypic analysis

The purpose of this study was to investigate the clinical relevance of subtypes categorized by immunophenotypic analysis in primary sinonasal lymphomas.

Apicidin potentiates the imatinib-induced apoptosis of Bcr–Abl-positive human leukaemia cells by enhancing the activation of mitochondria-dependent caspase cascades

Apicidin, a histone deacetylase inhibitor, is a novel cyclic tetrapeptide with potent antiproliferative activity against various cancer cells. We examined whether apicidin potentiates the imatinib‐induced apoptosis of Bcr–Abl‐positive human leukaemia cells. In K562 cells, the co‐administration of minimally toxic concentrations of imatinib and apicidin (imatinib/apicidin) for 48 h produced a marked increase in mitochondrial damage, processing of caspase cascades and apoptosis. Similar results were observed in leukaemic blasts obtained from patients with chronic myeloid leukaemia in blast crisis. Imatinib/apicidin co‐treatment for 48 h resulted in a near complete loss of the full‐length XIAP (X‐linked inhibitor of apoptosis) protein, with a corresponding increase in the 29‐kDa XIAP cleavage product. Both the degradation of XIAP and increased release of second mitochondria‐derived activator of caspase/direct IAP‐binding protein with low pI (Smac/DIABLO) into the cytosol were abrogated by pretreatment with the caspase‐3 inhibitor DEVD‐CHO. Imatinib/apicidin co‐treatment for 48 h produced a prominent decrease in Bcr–Abl protein levels in a caspase‐dependent manner. In summary, these data indicate that apicidin potentiates the imatinib‐induced apoptosis of Bcr–Abl‐positive leukaemia cells through the enhanced activation of the mitochondria‐dependent caspase cascades, accompanied by caspase‐dependent downregulation of Bcr–Abl and XIAP. These findings generate a rationale for further investigation of apicidin and imatinib as a potential therapeutic strategy in Bcr–Abl‐positive leukaemias.

Constitutive phosphorylation of FKHR transcription factor as a prognostic variable in acute myeloid leukemia

The transcription factor FKHR, which is controlled by Akt-PKB signaling, is involved in regulating cell cycle progression and cell death. In this study, the phosphorylation of FKHR was observed in 45 (73.8%) of 61 patients with acute myeloid leukemia (AML). The phosphorylation of Akt-PKB was found to be significantly associated with phospho-FKHR (P<0.001). Patients with phospho-FKHR had a significantly shorter overall survival than those without (P<0.05). In conclusion, the constitutive phosphorylation of FKHR was observed in the majority of AML, and the detection of phospho-FKHR might provide a new tool for identifying AML patients with an unfavorable outcome.

Primary NK/T cell lymphoma of the testis: A case report and review of the literature

We report a case of aggressive ‘nasal type’ natural killer (NK)/T cell lymphoma initially presenting as a testicular tumor in a Korean man, which quickly took a fatal course by widespread dissemination. Histologically, the testicular mass showed a diffuse dense infiltrate of medium-sized and atypical large lymphoid cells with angiocentric and angiodestructive infiltration and areas of coagulative necrosis on hematoxylin-eosin stained sections. Immunophenotyping by immunohistochemistry yielded surface markers consistent with NK/T cell lymphoma. The Epstein-Barr virus genome was detected by in situ hybridization. During involved-field irradiation and chemotherapy following radical orchiectomy, the tumor disseminated shortly to the skin and soft tissue of his anterior chest wall and central nervous system (CNS). Identical lymphoid infiltrates were present in the patient’s skin. CNS involvement was interpreted as having a leptomeningeal seeding. To the best of our knowledge, this is the 9th reported case of confirmed NK/T cell lymphoma arising from the testis. Relevant literature is reviewed, and the clinicopathologic features, natural history, and treatment options for primary testicular NK/T cell lymphoma are discussed.