Azacitidine induces demethylation of p16INK4a and inhibits growth in adult T-cell leukemia/lymphoma.

Adult T-cell leukemia/lymphoma (ATL) is one of the peripheral T-cell malignant neoplasms strongly associated with human T-cell leukemia virus type-I (HTLV-I). Although the viral transactivator protein Tax has been proposed to play a critical role in leukemogeneis, additional cellular events are required for the development of ATL. One of the genetic events of the disease is inactivation of tumor suppressor genes. The CDKN2A locus on chromosome 9p encodes 2 cell cycle regulatory proteins, p14ARF and p16INK4a, which share exon 2 using different reading frames. The p14ARF and p16INK4a genes have been implicated as tumor suppressor genes by their frequent mutation, deletion or promoter hypermethylation in a variety of human tumors. In this report, we describe the expression status of p14ARF and p16INK4a in 9 ATL cell lines (MT1, MT2, OKM3T, F6T, K3T, Oh13T, S1T, Su9T01 and HUT102). By reverse transcription polymerase chain reaction (RT-PCR), expression of p14ARF was not detected in one cell line (OKM3T), while expression of p16INK4a was not detected in 6 cell lines (OKM3T, MT1, MT2, Oh13T, S1T and Su9T01). In the OKM3T cell line, the shared exon 2 of the p14ARF/p16INK4a gene was deleted; however, the p16INK4a gene, was epigenetically inactivated in 5 other cells lines. In primary tumor cells obtained from ATL patients, p14ARF expression was absent in 6 of the 11 samples. We confirmed the methylation of the p16INK4a gene in MT1 and MT2 cells using the methylation-specific PCR (MSP) method. Treatment with 2.0 µM of Azacitidine (AZA), a demethylating agent, for 72 h restored p16INK4a transcript expression and induced growth inhibition in MT2 cells. Our results demonstrate that p16INK4a is epigenetically silenced in ATL. AZA offers a potential new therapeutic approach to improve the poor outcomes associated with ATL.

Effect of L-asparaginase combined with vincristine and prednisolone on acute myeloblastic leukemia (M0) associated with non-Hodgkin lymphoma.

A 66-year-old Japanese woman was referred to us because of severe anemia and fever and presented at our hospital. She was eventually diagnosed as having acute myeloblastic leukemia (AML; M0) with non-Hodgkin lymphoma (NHL). We investigated the therapeutic efficacy of L-asparaginase (L-Asp), vincristine and prednisolone for both her AML and NHL. Asparagine synthetase (AS) activity in her AML blast cells was undetectable. A lymph node biopsy specimen revealed NHL of the marginal zone B cell type. Complete remission (CR) of AML and NHL was achieved. CR of the AML lasted for 18 months without further consolidation therapy. We conclude that L-Asp can be an effective drug for the treatment of AML in which blasts are negative for AS.

Supplemental utility of nested PCR for the pathological diagnosis of disseminated trichosporonosis.

Disseminated trichosporonosis is known to be a severe opportunistic mycosis and has a high mortality rate. In autopsy cases, it is often difficult to diagnose as trichosporonosis because the causative Trichosporon species are pathologically similar to other fungi, especially the Candida species. Immunohistochemical analysis is essential for the differential diagnosis, but an antibody to Trichosporon is not available commercially. In the present study, we investigated the supplemental utility of nested polymerase chain reaction (PCR) for the pathological diagnosis of trichosporonosis from formalin-fixed and paraffin-embedded tissues. Total DNA was purified from 30 major organs in three autopsy cases, and Trichosporon DNA was specifically amplified by nested PCR using three sets of primers. Of 22 organs in which Grocott's stain was positive for fungal infection, 170- and 259-bp PCR products were detected in 20 (91%) and 12 (55%) organs, respectively. In short-term fixation (about 1 day), these bands were highly detected in ten (100%) and nine (90%) organs, whereas the detection efficiency tended to decrease after long-term fixation and decalcification. No PCR product of 412 bp was detected in any organs. These findings suggest that nested PCR from short-term-fixed tissues is useful for supportive pathological diagnosis of disseminated trichosporonosis.

Treatment of high-risk peripheral T-cell lymphomas other than anaplastic large-cell lymphoma with a dose-intensified CHOP regimen followed by high-dose chemotherapy. A single institution study.

We investigated the efficacy of a dose-intensified double-CHOP regimen followed by high-dose chemotherapy with or without peripheral blood stem cell transplantation (PBSCT) in 11 patients with four types of peripheral T-cell lymphoma (PTCL). Three of the 4 patients with unspecified PTCL (PTCLu) achieved complete response (CR); 1 patient relapsed and 1 died of secondary leukemia after consolidation therapy. All angioimmunoblastic T-cell lymphoma (AILT) and subcutaneous panniculitis-like T-cell lymphoma (SPTCL) patients achieved CR; 5 of 6 have remained disease free for more than 3 years. The patient with hepatosplenic lymphoma did not achieve CR even after PBSCT and underwent allogenic bone marrow transplantation (allo-BMT). Thus, our regimen appears to be effective for high-risk AILT and SPTCL. However, allo-BMT should be considered for high-risk of PTCLu and hepatosplenic T-cell lymphoma.

Felty's syndrome with chronic hepatitis and compatible autoimmune hepatitis: a case presentation.

A 68-year-old woman with Felty's syndrome was admitted to our hospital due to breathlessness. She was diagnosed as having rheumatoid arthritis at age 59 years. Abdominal computed tomography indicated ascites, splenomegaly and liver atrophy. She had no antigens or antibodies for hepatitis virus, or antibodies for mitochondria with the exception of antinuclear antibody. According to the International Autoimmune Hepatitis (AIH) scoring system, she was diagnosed as having chronic hepatitis, compatible with AIH. The association of Felty's syndrome with AIH is very rare and the most difficult problem to overcome is whether or not steroid therapy is necessary in patients with Felty's syndrome complicated by AIH.

[Bronchoesophageal fistula in a patient with untreated malignant lymphoma].

Bronchoesophageal fistulae associated with lymphomas are generally associated with chemo-radiotherapy. We report here an unusual case of lymphoma with a therapy-unrelated bronchoesophageal fistula. Previously, only 10 similar cases have been reported. A 70-year-old male was diagnosed as having gastric diffuse large B-cell lymphoma in May 1998. In January 1999, he noted a cough after eating and drinking. Because of the presence of a febrile temperature, productive cough and dyspnea, he was referred to our hospital and diagnosed as having aspiration pneumonia. Antibiotics did not improve his symptoms. When tracheal intubation was performed with bronchoscopy, a bronchoesophageal fistula was revealed. Malignant lymphoma cells were found around the fistula in the biopsy specimen. The patient died of pneumonia after treatment with airway stenting and chemotherapy. Induction of necrosis by chemotherapy or low blood flow with stenting and dopamine probably caused enlargement of the fistula.