Cytogenetics Unit

Vellore, India

Cytogenetics Unit

Vellore, India
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Luatti S.,University of Bologna | Castagnetti F.,University of Bologna | Marzocchi G.,University of Bologna | Baldazzi C.,University of Bologna | And 21 more authors.
Blood | Year: 2012

Additional chromosomal abnormalities (ACAs) in Philadelphia-positive cells have been reported in ∼5% of patients with newly diagnosed chronic myeloid leukemia (CML) in chronic phase (CP). Few studies addressing the prognostic significance of baselineACAs in patients treated with imatinib have been published previously. The European LeukemiaNet recommendations suggest that the presence of ACAs at diagnosis is a "warning" for patients in early CP, but there is not much information about their outcome after therapy with tyrosine kinase inhibitors. To investigate the role of ACAs in early CP CML patients treated with imatinib mesylate, we performed an analysis in a large series of 559 patients enrolled in 3 prospective trials of the Gruppo Italiano Malattie Ematologiche dell'Adulto Working Party on CML: 378 patients were evaluable and ACAs occurred in 21 patients (5.6%). The overall cytogenetic and molecular response rates were significantly lower and the time to response was significantly longer in patients with ACAs. The long-term outcome of patients with ACAs was inferior, but the differences were not significant. The prognostic significance of each specific cytogenetic abnormality was not assessable. Therefore, we confirm thatACAs constitute an adverse prognostic factor in CML patients treated with imatinib as frontline therapy. This study was registered with as NCT00514488 and NCT00510926. © 2012 by The American Society of Hematology.

Neat M.J.,Cytogenetics Unit | Foot N.J.,Cytogenetics Unit | Hicks A.,King's College London | Breen R.,Foundation Medicine | And 4 more authors.
Cytopathology | Year: 2013

Objectives: Patients with non-small cell lung cancer (NSCLC) positive for anaplastic lymphoma kinase (ALK) gene rearrangements may be treated successfully with the ALK inhibitor crizotinib. ALK copy-number abnormalities have also been described. In this study, we evaluated the suitability of fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) to determine ALK status in endobronchial ultrasound (EBUS)-derived cytology samples. Methods: Samples were obtained from 55 consecutive patients with NSCLC who had undergone EBUS-transbronchial needle aspiration (TBNA) according to our standard clinical protocols. All tumours had been screened previously for epithelial growth factor receptor (EGFR) and v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations. FISH, using commercially available ALK rearrangement-specific probes, was employed to assess ALK status. IHC using the ALK-1 monoclonal antibody (DAKO) was also performed. Results: FISH analysis was successful in 52 of 55 samples (94.5%); ALK rearrangement was demonstrated in 3 of 52 samples from patients with NSCLC (5.7%). ALK amplification was observed in 3 of 52 patient samples (5.7%) and an increase in ALK copy number was found in 28 of 52 patient samples (53.8%). IHC on cell blocks demonstrated ALK expression in one of three samples with ALK rearrangement. One patient sample had concomitant ALK rearrangement and KRAS mutation. Conclusions: We found FISH to be superior to IHC using the ALK-1 monoclonal antibody for the detection of ALK rearrangement in EBUS-TBNA cytology specimens in NSCLC, and also that ALK rearrangement can co-exist with KRAS mutation in the same tumour. © 2013 John Wiley & Sons Ltd.

PubMed | Cytogenetics Unit, Genotypic Technology, Christian Medical College and UMR 1131 Institute dHematologie
Type: Comparative Study | Journal: PloS one | Year: 2015

There is limited data on the clinical, cellular and molecular changes in relapsed acute promyeloytic leukemia (RAPL) in comparison with newly diagnosed cases (NAPL). We undertook a prospective study to compare NAPL and RAPL patients treated with arsenic trioxide (ATO) based regimens. 98 NAPL and 28 RAPL were enrolled in this study. RAPL patients had a significantly lower WBC count and higher platelet count at diagnosis. IC bleeds was significantly lower in RAPL cases (P=0.022). The ability of malignant promyelocytes to concentrate ATO intracellularly and their in-vitro IC50 to ATO was not significantly different between the two groups. Targeted NGS revealed PML B2 domain mutations in 4 (15.38%) of the RAPL subset and none were associated with secondary resistance to ATO. A microarray GEP revealed 1744 genes were 2 fold and above differentially expressed between the two groups. The most prominent differentially regulated pathways were cell adhesion (n=92), cell survival (n=50), immune regulation (n=74) and stem cell regulation (n=51). Consistent with the GEP data, immunophenotyping revealed significantly increased CD34 expression (P=0.001) in RAPL cases and there was in-vitro evidence of significant microenvironment mediated innate resistance (EM-DR) to ATO. Resistance and relapse following treatment with ATO is probably multi-factorial, mutations in PML B2 domain while seen only in RAPL may not be the major clinically relevant cause of subsequent relapses. In RAPL additional factors such as expansion of the leukemia initiating compartment along with EM-DR may contribute significantly to relapse following treatment with ATO based regimens.

Parihar M.,Cytogenetics Unit | Koshy B.,Christian Medical College | Srivastava V.M.,Cytogenetics Unit
Indian Journal of Human Genetics | Year: 2013

Chromosomal abnormalities are seen in nearly 1% of live born infants. We report a 5-year-old boy with the clinical features of Down syndrome, which is the most common human aneuploidy. Cytogenetic analysis showed a mosaicism for a double aneuploidy, Down syndrome and XYY. The karyotype was 47, XY,+21[19]/48, XYY,+21[6]. ish XYY (DXZ1 × 1, DYZ1 × 2). Mosaic double aneuploidies are very rare and features of only one of the aneuploidies may predominate in childhood. Cytogenetic analysis is recommended even if the typical features of a recognized aneuploidy are present so that any associated abnormality may be detected. This will enable early intervention to provide the adequate supportive care and management.

Martin-Perez D.,Lymphoma Group | Sanchez E.,Hospital Nuestra Senora del Prado | Maestre L.,Monoclonal Antibodies Unit | Suela J.,Cytogenetics Unit | And 6 more authors.
American Journal of Pathology | Year: 2010

Polycomb proteins are known to be of great importance in human cancer pathogenesis. SUZ12 is a component of the Polycomb PRC2 complex that, along with EZH2, is involved in embryonic stem cell differentiation. EZH2 plays an essential role in many cancer types, but an equivalent involvement of SUZ12 has not been as thoroughly demonstrated. Here we show that SUZ12 is anomalously expressed in human primary tumors, especially in mantle cell lymphoma (MCL), pulmonary carcinomas and melanoma, and is associated with gene locus amplification in some cases. Using MCL as a model, functional and genomic studies demonstrate that SUZ12 loss compromises cell viability, increases apoptosis, and targets genes involved in central oncogenic pathways associated with MCL pathogenesis. Our results support the hypothesis that the abnormal expression of SUZ12 accounts for some of the unexplained features of MCL, such as abnormal DNA repair and increased resistance to apoptosis. Copyright © American Society for Investigative Pathology.

Philip C.,Christian Medical College | George B.,Christian Medical College | Ganapule A.,Christian Medical College | Korula A.,Christian Medical College | And 11 more authors.
British Journal of Haematology | Year: 2015

The management of acute myeloid leukaemia (AML) in India remains a challenge. In a two-year prospective study at our centre there were 380 newly diagnosed AML (excluding acute promyelocytic leukaemia, AML-M3) patients. The median age of newly diagnosed patients was 40 years (range: 1-79; 12·3% were ≤ 15 years, 16·3% were ≥ 60 years old) and there were 244 (64·2%) males. The median duration of symptoms prior to first presentation at our hospital was 4 weeks (range: 1-52). The median distance from home to hospital was 580 km (range: 6-3200 km). 109 (29%) opted for standard of care and were admitted for induction chemotherapy. Of the 271 that did not take treatment the major reason was lack of financial resources in 219 (81%). There were 27 (24·7%) inductions deaths and of these, 12 (44·5%) were due to multidrug-resistant gram-negative bacilli and 12 (44·5%) showed evidence of a fungal infection. The overall survival at 1 year was 70·4% ± 10·7%, 55·6% ± 6·8% and 42·4% ± 15·6% in patients aged ≤15 years, 15 - 60 years and ≥60 years, respectively. In conclusion, the biggest constraint is the cost of treatment and the absence of a health security net to treat all patients with this diagnosis. © 2015 The Authors.

Chendamarai E.,Christian Medical College | Balasubramanian P.,Christian Medical College | George B.,Christian Medical College | Viswabandya A.,Christian Medical College | And 12 more authors.
Blood | Year: 2012

Data on minimal residual disease (MRD) monitoring in acute promyelocytic leukemia (APL) are available only in the context of conventional all-trans retinoic acid plus chemotherapy regimens. It is recognized that the kinetics of leukemia clearance is different with the use of arsenic trioxide (ATO) in the treatment of APL. We undertook a prospective peripheral blood RT-PCR-based MRD monitoring study on patients with APL treated with a single agentATO regimen.Atotal of 151 patients were enrolled in this study. A positive RT-PCR reading at the end of induction therapy was significantly associated on a multivariate analysis with an increased risk of relapse (relative risk = 4.9; P = .034). None of the good risk patients who were RT-PCR negative at the end of induction relapsed. The majority of the relapses (91%) happened within 3 years of completion of treatment. After achievement of molecular remission, the current MRD monitoring strategy was able to predict relapse in 60% of cases with an overall sensitivity and specificity of 60% and 93.2%, respectively. High-risk group patients and those that remain RT-PCR positive at the end of induction are likely to benefit from serial MRD monitoring by RT-PCR for a period of 3 years from completion of therapy. © 2012 by The American Society of Hematology.

PubMed | Cytogenetics Unit and Christian Medical College
Type: | Journal: International journal of laboratory hematology | Year: 2016

The hallmark of chronic myeloid leukemia (CML) is the presence of Philadelphia chromosome, its resultant fusion transcript (BCR-ABL1), and fusion protein (p210). Alternate breakpoints in BCR (m-bcr, -bcr, and others) or ABL1 result in the expression of few rare fusion transcripts (e19a2, e1a2, e13a3, e14a3) and fusion proteins (p190, p200, p225) whose exact clinical significance remains to be determined.Our study was designed to determine the type and frequency of BCR-ABL1 fusion transcripts in 1260 CML patients and to analyze the prognosis and treatment response in patients harboring rare BCR-ABL1 fusion transcripts.The frequency of various BCR-ABL1 fusion transcripts was as follows: e14a2 (60%), e13a2 (34.3%), e1a2 (1.2%), e1a2 + e13a2 (2.0%), e1a2 + e14a2 (1.8%), e19a2 (0.3%), and e14a3 (0.3%). CML patients with e1a2 transcripts had higher rates of disease progression, resistance, or suboptimal response to imatinib and failed to achieve major molecular response.Characterization of the specific fusion transcript in CML patients is important owing to the difference in prognosis and response to therapy in addition to the conventional need for monitoring treatment response. CML patients with e1a2 transcripts have to be closely monitored due to the high incidence of disease progression and treatment resistance/failure.

PubMed | Cytogenetics Unit, Bangalore Baptist Hospital, Seacroft Hospital, Reproductive Medicine Unit and 2 more.
Type: Journal Article | Journal: Journal of human reproductive sciences | Year: 2016

To estimate the prevalence of chromosomal abnormalities and Y chromosome microdeletion among men with azoospermia and severe oligozoospermia and its correlation with successful surgical sperm retrieval.A prospective study in a tertiary level infertility unit.In a prospective observation study, men with azoospermia and severe oligozoospermia (concentration <5 million/ml) attending the infertility center underwent genetic screening. Peripheral blood karyotype was done by Giemsa banding. Y chromosome microdeletion study was performed by a multiplex polymerase chain reaction.The study group consisted of 220 men, 133 of whom had azoospermia and 87 had severe oligozoospermia. Overall, 21/220 (9.5%) men had chromosomal abnormalities and 13/220 (5.9%) men had Y chromosome microdeletions. Chromosomal abnormalities were seen in 14.3% (19/133) of azoospermic men and Y chromosome microdeletions in 8.3% (11/133). Of the 87 men with severe oligozoospermia, chromosomal abnormalities and Y chromosome microdeletions were each seen in 2.3% (2/87). Testicular sperm aspiration was done in 13 men and was successful in only one, who had a deletion of azoospermia factor c.Our study found a fairly high prevalence of genetic abnormality in men with severe semen abnormalities and a correlation of genetic abnormalities with surgical sperm retrieval outcomes. These findings support the need for genetic screening of these men prior to embarking on surgical sperm retrieval and assisted reproductive technology intracytoplasmic sperm injection.

PubMed | Cytogenetics Unit, St Jude Childrens Research Hospital and Christian Medical College
Type: Journal Article | Journal: Cancer chemotherapy and pharmacology | Year: 2016

Chemotherapy drug resistance and relapse of the disease have been the major factors limiting the success of acute myeloid leukemia (AML) therapy. Several factors, including the pharmacokinetics (PK) of Cytarabine (Ara-C) and Daunorubicin (Dnr), could contribute to difference in treatment outcome in AML.In the present study, we evaluated the plasma PK of Dnr, the influence of genetic polymorphisms of genes involved in transport and metabolism of Dnr on the PK, and also the influence of these factors on clinical outcome. Plasma levels of Dnr and its major metabolite, Daunorubicinol (DOL), were available in 70 adult de novo AML patients. PK parameters (Area under curve (AUC) and clearance (CL)) of Dnr and DOL were calculated using nonlinear mixed-effects modeling analysis performed with Monolix. Genetic variants in ABCB1,ABCG2, CBR1, and CBR3genes as well as RNA expression of CBR1, ABCB1, and ABCG2 were compared with Dnr PK parameters.The AUC and CL of Dnr and DOL showed wide inter-individual variation. Patients with an exon1 variant of rs25678 in CBR1 had significantly higher plasma Dnr AUC [p=0.05] compared to patients with wild type. Patients who achieved complete remission (CR) had significantly lower plasma Dnr AUC, Cmax, and higher CL compared to patients who did not achieve CR.Further validation of these findings in a larger cohort of AML patients is warranted before establishing a therapeutic window for plasma Dnr levels and targeted dose adjustment.

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