Identification of the BRAF V600E mutation in Japanese patients with hairy cell leukemia and related diseases using a quenching probe method.

Hairy cell leukemia (HCL) is a rare B-cell lymphoid malignancy that is difficult to distinguish from other morphological variants. The frequency of HCL has not been determined accurately in Japan. Recent studies revealed that the BRAF V600E mutation is the causal genetic event in HCL. We assessed the BRAF mutation in Japanese patients with HCL and related diseases using the quenching probe (QP) method, a single-nucleotide polymorphism detection system, and evaluated the incidence rate of HCL among Japanese patients with chronic lymphocytic leukemia, and related diseases. We identified 18 cases (33.3%) harboring the BRAF mutation among 54 patients diagnosed with, or suspected of having HCL. Of BRAF V600E-positive patients, 7 were only detected using the QP method, not by direct sequencing, whereas 11 were positive using both tests. In a larger cohort of Japanese patients diagnosed with chronic lymphoid leukemia or related diseases, the frequency of HCL was 4%. Patients with the BRAF V600E mutation had a significantly higher frequency of neutropenia, thrombocytopenia, and elevated soluble interleukin-2 receptor and common B-cell surface markers than patients without the mutation. Our results confirm that BRAF V600E-positive HCL is a relatively rare disorder in the Japanese leukemia patient population.

Mutation Profile of B-Raf Gene Analyzed by fully Automated System and Clinical Features in Japanese Melanoma Patients.

BRAF gene mutations have been observed in 30-50 % of malignant melanoma patients. Recent development of therapeutic intervention using BRAF inhibitors requires an accurate and rapid detection system for BRAF mutations. In addition, the clinical characteristics of the melanoma associated with BRAF mutations in Japanese patients have not been investigated on a large scale evaluation. We recently established quenching probe system (QP) for detection of an activating BRAF mutation, V600E and evaluated 113 melanoma samples diagnosed in Saga University Hospital from 1982 to 2011. The QP system includes fully automated genotyping, based on analysis of the probe DNA melting curve, which binds the target mutated site using a fluorescent guanine quenched probe. BRAF mutations were detected in 54 of 115 (47 %) including 51 of V600E and 3 of V600 K in Japanese melanoma cases. Among clinical subtypes of melanoma, nodular melanoma showed high frequency (12 of 15; 80 %) of mutation followed by superficial spreading melanoma (13 of 26; 50 %). The QP system is a simple and sensitive method to determine BRAF V600E mutation, and will be useful tool for patient-oriented therapy with BRAF inhibitors.

Measurement of ankle plantar flexor spasticity following stroke: Assessment of a new quantitative tool.

OBJECTIVE: To assess the ability of a newly developed portable instrument (the Electric Spastic Ankle Measure (E-SAM)) to quantitatively measure ankle plantar flexor muscle tone and spasticity. DESIGN: Comparison of quantitative measurements of the E-SAM with those obtained manually with the Modified Ashworth Scale (MAS). PARTICIPANTS: Seven adult men with stroke of more than 8 months' duration with a MAS score of 3, and 7 healthy age-matched control subjects. MAIN OUTCOME MEASURES: Quantitative measurements of the reactive and viscoelastic components of muscle tonus and spasticity. RESULTS: Analysis of the pooled data of all subjects revealed 2 components: an initial negative peak (indicating visco-elasticity), and subsequent positive peaks (denoting reactive contractions of the plantar flexor muscles). Positive, reactive contraction, peaks of the subjects with stroke were significantly higher than those of age-matched controls (p<0.01, t-test). CONCLUSION: The E-SAM appears to provide meaningful information on muscle tone and spasticity that is more specific and quantitative than that obtained with the MAS. While further study is necessary, this instrument shows promise as an easy-to-use clinical and research tool for the measurement of spasticity and muscle viscosity.

Hairy Cell Leukemia with Systemic Lymphadenopathy: Detection of BRAF Mutations in Both Lymph Node and Peripheral Blood Specimens.

A 47-year-old woman with pancytopenia, excessive systemic lymphadenopathy and splenomegaly was referred to our hospital. The peripheral blood (PB) smear findings indicated neutropenia with lymphoid cells exhibiting hairy projections, while the histological findings of the cervical lymph node (LN) suggested hairy cell leukemia (HCL). In addition, the BRAF V600E mutation was detected, and the immunoglobulin gene rearrangement patterns were identical in both the cervical LN and PB specimens. Based on these findings, we diagnosed the patient with systemic lymphadenopathy due to HCL. This is the first report of a BRAF mutation detected in both the PB and LN at the onset of HCL.

Correlation between plasma DNA and tumor status in an animal model.

Overcoming metastasis is one of the most important issues with lung cancer. Since metastasis arises through complex steps, a suitable animal model is indispensable for investigation of metastasis. To establish an animal model reflecting human metastatic lung cancers, we used NOD/SCID/Jak3null (NOJ) mice, which exhibit deficiencies in NK cell activity, macrophage and dendritic cell function, and complement activation, as well as T and B cell deficiencies. After screening twenty human lung cancer cell lines through expression patterns of E-cadherin and vimentin according to epithelial mesenchymal transition features, an H1975 cell line carrying EGFR mutations, L858R and T790M, was selected for investigation. Inoculation of the cells into the dorsal flanks caused systemic metastases after one month in lymph nodes, liver, lung, and peritoneum, suggesting that metastases occurred both lymphogenically and hematogenously. We confirmed the existence of H1975 cells in metastatic lesions by detection of T790M and L858R using the mutation-biased PCR and quenching probe (MBP-QP) system previously established in our laboratory. In addition, tumor-derived plasma DNA could be detected using the MBP-QP method. The amount of tumor-derived DNA was associated with tumor volume, whereas an unrelated large amount of tumor-derived DNA was circulating in the presence of metastasis. We present a novel animal model with systemic metastasis with human lung cancer cells. The amount of tumor derived DNA would be related with tumor volume and tumor progression such as metastasis.

Development of lymphoproliferative diseases by hypoxia inducible factor-1alpha is associated with prolonged lymphocyte survival.

Hypoxia-inducible factor-1alpha (HIF-1 alpha) plays an essential role in the regulation of various genes associated with low oxygen consumption. Elevated expression of HIF-1alpha has been reported to be associated with tumor progression, invasion and metastasis in many cancers. To investigate the role of HIF-1alpha in tumor development and metastasis, we established transgenic mice constitutively expressing HIF1A gene under regulation of the cytomegalovirus gene promoter. Although HIF-1alpha protein levels varied among organs, expression of HIF1A mRNA in most organs gradually increased in an age-dependent manner. The transgenic mice showed no gross morphological abnormality up to 8 weeks after birth, although they subsequently developed tumors in the lymphoid, lung, and breast; the most prominent tumor was lymphoma appearing in the intestinal mucosa and intra-mesenchymal tissues. The prevalence of tumors reached 80% in 13 months after birth. The constitution of lymphocyte populations in the transgenic mice did not differ from that in wild-type mice. However, lymphocytes of the transgenic mice revealed prolonged survival under long-term culture conditions and revealed increased resistance to cytotoxic etoposide. These results suggest that HIF-1alpha itself is not oncogenic but it may play an important role in lymphomagenesis mediated through the prolonged survival of lymphocytes in this transgenic mouse model.

A fully integrated and automated detection system for single nucleotide polymorphisms of UGT1A1 and CYP2C19.

The need for examinations of single nucleotide polymorphisms (SNPs) on drug metabolizing enzymes is accelerating. Especially, SNPs of UTG1A1 and CYP2C19 are important for patients who are treated with irinotecan and proton pump inhibitors, respectively. Thus, a method for the rapid, fully automated, and accurate measurement of these SNPs is desired. We genotyped 109 Japanese volunteers for UGT1A1*6, UGT1A1*28, CYP2C19*2, and CYP2C19*3 with the quenching probe (QP) method. Only 90 min after whole blood was applied, QP method enabled to detect these SNPs automatically. The results obtained by QP method were absolutely identical to those examined by the conventional direct sequencing. These findings indicate that the QP method will enable point-of-care testing in clinical laboratories and patient-oriented therapy with its convenience and speed for patients who are treated with irinotecan or proton pump inhibitors.

NK314 potentiates antitumor activity with adult T-cell leukemia-lymphoma cells by inhibition of dual targets on topoisomerase II{alpha} and DNA-dependent protein kinase.

Adult T-cell leukemia-lymphoma (ATL) is an aggressive disease, incurable by standard chemotherapy. NK314, a new anticancer agent possessing inhibitory activity specific for topoisomerase IIα (Top2α), inhibited the growth of various ATL cell lines (50% inhibitory concentration: 23-70nM) with more potent activity than that of etoposide. In addition to the induction of DNA double-strand breaks by inhibition of Top2α, NK314 induced degradation of the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs), resulting in impaired DNA double-strand break repair. The contribution of DNA-PK to inhibition of cell growth was affirmed by the following results: NK314 inhibited cell growth of M059J (a DNA-PKcs-deficient cell line) and M059K (a cell line with DNA-PKcs present) with the same potency, whereas etoposide exhibited weak inhibition of cell growth with M059K cells. A DNA-PK specific inhibitor, NU7026, enhanced inhibitory activity of etoposide on M059K as well as on ATL cells. These results suggest that NK314 is a dual inhibitor of Top2α and DNA-PK. Because ATL cells express a high amount of DNA-PKcs, NK314 as a dual molecular targeting anticancer agent is a potential therapeutic tool for treatment of ATL.

Uncommon case of chronic myeloid leukemia with multiple myeloma.

We describe a 72-year-old woman who was diagnosed with asymptomatic multiple myeloma (MM) while being treated for Philadelphia (Ph)-positive chronic myeloid leukemia (CML) with imatinib mesylate (400 mg/day). The diagnosis of CML was based on the presence of the Ph chromosome and chimeric BCR-ABL messenger RNA. Three months after starting imatinib mesylate treatment, the patient achieved a complete cytogenetic response. However, bone marrow analysis at that time demonstrated plasmacytosis, and paraprotein (IgG, kappa-type) was also detected. Hypercalcemia, renal failure, anemia, and bone lesions were not observed, which suggested that asymptomatic MM had developed. The coexistence of CML and MM is an extremely uncommon event that has only been reported in 12 cases. We discuss the relationship between CML and MM.

Gangrenous cheilitis associated with all-trans retinoic acid therapy for acute promyelocytic leukemia.

A 67-year-old Japanese woman who presented with erythema on the abdomen and pancytopenia was found to have acute promyelocytic leukemia (APL). A skin biopsy revealed invasion of APL cells. She was started on induction treatment with all-trans retinoic acid (ATRA) at 45 mg/m(2). On day 4, the leukemic cell number had increased to over 1.0 x 10(9)/L. Consequently, chemotherapy with idarubicin and cytarabine was initiated. On day 10, dryness of the lips appeared. The lower lip swelled and developed painful black eschars. A high fever was also present. Despite discontinuing ATRA on day 20 and administering antibiotics, an anti-fungal agent and valaciclovir, these signs did not improve. Histopathologically, the biopsied lip revealed infiltration of neutrophils and vasculitis. The patient was given ATRA on days 29 and 30 due to an increase in APL cell numbers, after which the gangrenous cheilitis extended over the whole lip. On day 49, the patient was started on re-induction treatment with arsenic trioxide. She achieved complete remission and the gangrenous cheilitis slowly healed over the following 8 weeks. Since the clinical features of the gangrenous cheilitis in this case were similar to those of ATRA-associated scrotal ulcers, it appears that activated neutrophils derived from differentiated APL cells may have caused the gangrenous cheilitis. Physicians should be alert to the development of gangrenous cheilitis during treatment with ATRA.

Clinico-pathological characteristics of p63 expression in B-cell lymphoma.

A member of the family of p53-related genes, p63 plays a role in regulating epithelial proliferation and differentiation programs, but the pathological and clinical meaning of p63 in B-cell lymphoma has not been elucidated. We investigated the expression pattern of p63 in B-cell malignancies, and evaluated the correlation between the expression of p63 and other germinal center markers. Ninety-eight B-cell lymphomas (28 FCL, 5 MCL, and 65 DLBCL) were analyzed by immunohistochemical examination for p63, bcl-6, CD10 and MUM-1 proteins, and for rearrangement of bcl-2/IgH. Expression of p63 was observed in the nuclei of tumor cells obtained from 15 of 28 (54%) FCL, 22 of 65 (34%) DLBCL, but none of 5 MCL. In DLBCL, the expression of p63 and bcl-6 showed a significant correlation (P < 0.02), but no correlation was observed between p63 and expression of CD10, MUM-1, or bcl-2/IgH rearrangement. RT-PCR revealed that TAp63alpha-type transcripts, a possible negative regulator of transcriptional activation of p21 promoter, were major transcripts in B-cell lymphoma tissues. As for prognostic significance, only patients in the p63 positive group of FCL died, and in the non-germinal center group, the p63 positive cases appeared to have inferior overall survival than other groups in DLBCL. Our preliminary results suggested that p63 expression is a disadvantageous factor for prognosis in this subgroup of B-cell lymphomas.

Two cases of antinuclear antibody negative lupus showing increased proportion of B cells lacking RP105.

B cells lacking RP105 molecule, a member of the Toll-like receptor family, were increased in the peripheral blood of 2 patients with antinuclear antibody (ANA) negative systemic lupus erythematosus (SLE). The increased proportion of RP105-lacking B cells was associated with disease activity in patients with ANA-negative SLE. When there are no significant serological markers for SLE, analysis of expression of RP105 may be helpful in evaluation of activity in ANA-negative SLE. We describe a new approach, using phenotyping of B cells, to evaluate activity of ANA-negative SLE.