[Blastic natural killer cell leukemia--one case report and review of literature].

OBJECTIVE: To report a case of blastic natural killer cell leukemia with an aggressive clinical course. METHODS: The characteristics of blastic NK cell leukemia and its treatment were discussed with review of literatures. RESULTS: After combination chemotherapy and spinal cord segmental radiotherapy, the patient entered hematological remission, but the extramedullary lesion remained unchanged. CONCLUSION: Blastic NK cell leukemia has an aggressive clinical course with poor response to treatment and unfavorable prognosis.

[Expression of survivin, Fas, bcl-2 and bax in bone marrow cells from acute myeloid leukemia patients and its clinical significance].

UNLABELLED: To study the clinical significance of the expression of antiapoptosis gene, survivin and bcl-2, and proapoptosis gene, Fas and bax, in acute myeloid leukemia (AML), RT-PCR was used to examine the expression of survivin and flow cytometry (FCM) to detect the expression of Fas, bcl-2, bax and bcl-2/bax ratio in 68 cases of AML. The results demonstrated that: (1) The positivity of survivin mRNA expression was significantly higher in AML compared to control (70.6% vs 30%, P < 0.05). (2) The expression of Fas and bcl-2 in AML before treatment was significantly higher than that in control (P < 0.001), but the bax expression did not (P > 0.05). (3) The survivin-positive AML cases showed a significantly lower Fas and higher bcl-2 expression in comparison with survivin-negative ones (P < 0.01 and P < 0.001, respectively), but the bax did not (P > 0.01). (4) Survivin-positive AML cases had a lower CR rate as compared with survivin-negative cases (64.6% vs 90%, P < 0.05). (5) The survivin-positive CR cases showed a decreased expression of Fas and bcl-2 after treatment in comparison with pretreatment expression (P < 0.001), but the bax expression remained unchanged before and after therapy. The survivin-positive NR cases showed a significantly decreased Fas and increased bcl-2 expression as compared with pretreatment expression (P < 0.001). bcl-2/bax ratio was also significantly higher in NR cases. IN CONCLUSION: 70.6% AML cases showed positive for survivin expression with a lower CR rate, the survivin-positive AML showed a low Fas with high bcl-2 expression and bcl-2/bax ratio as compared to the survivin-negative cases.

[Clinic Significance of Expression of bcl-2 and bax Gene in Patients with Acute Leukemia and its Relationship with mdr-1 Gene Expression]

It is generally accepted that the inhibition of apoptosis is one of the mechanism of drug resistance to tumor. Members of the bcl-2 gene family are the most important regulators in apoptosis. The purpose of this study is to evaluate the value of expression of bcl-2 and bax gene in predicting the prognosis of acute leukemia patients, and to explore the relationship between bcl-2 and bax expression and drug resistance. Seventy patients with acute leukemia entered this study. Expressions of bcl-2, bax and mdr-1 gene were measured by RT-PCR method and FCM. The result showed that: bcl-2 had been widely detected in specimens of blood or bone marrow from acute leukemia patients, the expression levels were much higher than those in normal control (1.46 vs 0.71, P < 0.05), bax expression levels and bax/bcl-2 ratio in patients had no significant difference with the control. No relationships were found between the expression levels of bcl-2 and bax and AL patients' age, sex, platelet counts, hemoglobin levels, percentage of marrow blasts, FAB classification, and S + G(2)M%. Both Bcl-2 protein expression (34.6% vs 69.2%, P < 0.03) and bax/bcl-2 mRNA ratio (37.1% vs 82.9%, P < 0.01) were associated with response to therapy and CR rate, bax/bcl-2 ratio also influences the overall survival time. There was no relationship between bcl-2 and bax expression levels and mdr-1 expression levels.