Qiu Hr

The application of fluorescence in situ hybridization in detecting chronic myeloid leukemia

OBJECTIVE To evaluate the clinical significance of the application of fluorescence in situ hybridization (FISH) in detecting chronic myeloid leukemia (CML). METHODS Chromosome preparation was made by using 24-hour culture. FISH technique using dual color dual fusion (DC-DF) BCR/ABL probe was performed in all 158 cases and R-banding was also employed for karyotyping in some patients. RESULTS Among the 158 cases, 98 cases were Ph positive, of which 69 cases (70.4%) were typical FISH pattern (1R1G2F), the other 29 cases (29.6%) showed 12 different types of atypical FISH pattern. The most frequent atypical patterns found were 1R1G1F in 7 cases (7.1%), 2R1G1F in 5 cases (5.1%), 1R1G2F and 1R1G3F in 4 cases (4.1%), 2R2G1F in 3 cases (3.1%). Karyotype analysis on 18 CML cases with atypical FISH patterns demonstrated that the atypical FISH patterns were due to variant translocation in 3 cases; the additional third signal was because of a supernumerary Ph chromosome. The karyotyping results did not conform to FISH results in four cases suggesting the conceivable mistakes in karyotyping. The 1R1G1F signal pattern seen in 3 cases with classical t(9;22) resulted from the deletion of derivative chromosome 9. The 1R1G2F signal pattern detected in 40% to 64% of interphase cells of 3 cases without Ph chromosome by conventional cytogenetic analysis suggested a submicroscopic translocation. Three cases treated with Glivec or bone marrow transplantation showed normal karyotypes with a small amount of BCR/ABL positive cells by FISH detection. CONCLUSION FISH technique is of great value for the diagnosis of CML and confirmation of variant translocation, occult Ph translocation, derivative chromosome 9 deletion, therapeutic effect of interferon and Glivec as well as detection of minimal residual disease after bone marrow transplantation.

Investigation of the molecular changes in patients with multiple myeloma by fluorescence in situ hybridization

OBJECTIVE To investigate the incidence and prognosis of 1q21 amplification, 13q14 deletion, TP53 gene deletion and IgH translocation in patients with multiple myeloma (MM). METHODS Interphase fluorescence in situ hybridization (I-FISH) with four different specific probes for the regions containing 1q21, 13q14.3 (D13S319), 14q32 and TP53 gene were performed in 43 MM patients. RESULTS Among the 43 MM patients, 1q21 amplification was observed in 28 (65.1%) cases, 13q14 deletion in 30 (69.7%) cases, TP53 gene deletion in 8 (18.6%) cases, and IgH translocation in 29 (67.4%) cases. The mortality of MM patients with 1q21 amplification, 13q14 deletion or TP53 gene deletion was higher than those without them. CONCLUSION There is high frequency of 1q21 amplification, 13q14 deletion, TP53 gene deletion and IgH translocation in multiple myeloma, and 1q21 amplification, 13q14 deletion and TP53 gene deletion are poor prognosis factors for MM patients.

[Investigation of 1q21 amplification in patients with multiple myeloma using I-FISH and cIg-FISH].

OBJECTIVE To investigate the prevlance of 1q21 amplification in patients with multiple myeloma (MM) and its correlation with the progression and prognosis of the disease. METHODS 1q21 amplification was detected in 48 patients with MM using cytoplasmic light chain immunofluorescence with fluorescence in situ hybridization analysis (cIg-FISH) and interphase fluorescence in situ hybridization (I-FISH) analysis combined with CD138 immunomagnetic cell sorting (MACS). RESULTS 1q21 amplification (≥ 3 red signals) was detected in 26/48(54.2%) cases by cIg-FISH and 31/48 (64.6%) cases by I-FISH combined with CD138 MACS. There was a good consistency between the two methods (P>0.05). The mortality of patients with 1q21 amplification was significantly higher than those without (P< 0.05). No significant difference was detected in terms of sex, age, Durie-Salmon stage, subgroup and international staging system (ISS) stage between patients with 1q21 amplification and those without (P>0.05). CONCLUSION The frequency of 1q21 amplification in MM is high. There was also an association between the amplification and poor prognosis. cIg-FISH is consistent with CD138 MACS combined with I-FISH.

Cytogenetic study of mantle cell lymphoma

OBJECTIVE To explore the cytogenetic features of mantle cell lymphoma (MCL). METHODS Bone marrow cells from 18 MCL patients with bone marrow invasion were cultured for 24 hours, then routine karyotype analysis was performed with R-banding technique. Interphase fluorescence in situ hybridization (FISH) and a panel of 5 probes, including CCND1/IgH, CEP12, D13S319, p53 gene and ATM gene, were used to investigate the cytogenetic features of the samples. RESULTS Chromosome aberrations were found in 9 (64.3%, 9/14) patients by conventional cytogenetics (CC), 8(57.1%, 8/14) patients had the aberration of t(11; 14), 6(42.9%, 6/14) had complex aberrant karyotypes, of which 2 (14.3%, 2/14) had highly complex aberrant karyotypes. A total of 28 abnormalities were detected, among them 19 (67.9%) were structural abnormalities, the other 9 (32.1%) were numerical aberrations. The aberration of t(11; 14) was found in all 18 (100%) patients with MCL by FISH. Secondary cytogenetic aberrations were detected in 14 patients by FISH. The most common abnormality was del(11q22.3) (57.1%), the rate of aberrations for del(17p13), + 12 and del(13q14) were 42.9%, 35.7% and 21.4%, respectively. Two (14.3%) and 4 (28.6%) patients were detected to have combinations of 2 and 3 aberrations. CONCLUSION In addition to t(11; 14), most MCL patients have other chromosome aberrations, especially complex aberrant karyotype.

Detection of complex chromosomal aberrations in patients with multiple myeloma using multiplex fluorescence in situ hybridization

OBJECTIVE To explore the value of multiplex fluorescence in situ hybridization (M-FISH) in the detection of the complex chromosomal aberrations (CCAs) in multiple myeloma (MM). METHODS M-FISH was used in 10 MM patients with CCAs detected by conventional cytogenetics (CC) using R-banding to refine the rearrangement of CCAs and identify the characteristics of marker chromosome. RESULTS M-FISH confirmed the 29 structural aberrations shown by CC analysis, and also confirmed the specific source of 21 types of chromosomal aberration, which were not detected by CC analysis. Among them, t(2;15)(q33;q22), t(6;7)(q23;q34), t(8;11) (q24;q23), t(1;14)(q10;q32) and t(X;1)(q26;q25) were new chromosomal aberrations. The median survival time of 9 MM patients with CCAs was 23 months and evidently shorter than that of MM patients without CCAs, with the mean survival time being 34 months. CONCLUSION M-FISH could refine CCAs in MM patients, find or correct the missed or misidentified abnormalities analyzed by CC. It has provided one of the essential methods for the research of chromosomal aberrations in MM.

[Detection of the Philadelphia chromosome in adult B-lineage acute lymphoblastic leukemia using dual-color dual-fusion interphase fluorescence in situ hybridization].

OBJECTIVE To investigate the incidence of Philadelphia chromosome (Ph) in adult B-lineage acute lymphoblastic leukemia (B-ALL). METHODS One hundred and twelve adult patients with previously untreated B-ALL were prospectively investigated by interphase dual-color dual-fusion fluorescence in situ hybridization (DD-FISH) with two-color break apart probe BCR-ABL and the results were compared with that of conventional cytogenetics (CC). RESULTS The incidence of Ph chromosome was 17.98% (16/89) and 31.25% (35/112) by CC and DD-FISH, respectively. The mean positive rate of Ph+cells by FISH was 66.23% (ranging 18.5%-99%). Of the 35 Ph+ALL patients by FISH, 25 were successfully karyotyped by CC which included 5 normal karyotypes, 20 abnormal karyotypes including 16 Ph chromosome and 13 complex abnormalities. CONCLUSION The incidence of Ph chromosome was 31.25% in adult with B-ALL. DD-FISH with BCR-ABL probe provides a powerful technique for the diagnosis of Ph+B-ALL. It is an important supplement to the CC analysis. DD-FISH technique should be used as a routine method for the diagnosis for adult acute B-ALL.