Publications by authors named "Mahmoud Mansouri"

18 Publications

  • Page 1 of 1

miR-193a-5p as a promising therapeutic candidate in colorectal cancer by reducing 5-FU and Oxaliplatin chemoresistance by targeting CXCR4.

Int Immunopharmacol 2021 Mar 8;92:107355. Epub 2021 Jan 8.

Immunology Research Center, Tabriz University of Medical Sciences, Tabriz 5166614766, Iran; Department of Immunology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz 5166614766, Iran; Department of Immunology, Center of Clinical Medicine and Laboratory, Jiangsu University, Zhenjiang 212013, Jiangsu Province, China. Electronic address:

Colorectal cancer (CRC) is one of the most common causes of cancer-related deaths worldwide. The role of microRNAs (miRNAs/miRs) as small (19-25 nucleotides in length) non-coding RNA molecules that modify gene expression has been shown in several types of cancer. 5-Fluorouracil (5-FU) and oxaliplatin (Ox) are two common chemotherapeutic agents used to treat cancer. The present study aimed to evaluate the expression levels of miR-193a-5p in CRC, and its effect on the C-X-C Motif Chemokine Receptor 4 (CXCR4) target gene alone and in combination with chemotherapeutic drugs, to determine its possible role in chemoresistance. CRC tissues and adjacent non-cancerous tissue were obtained from 67 patients who had undergone surgery to determine the expression levels of miR-193a-5p and CXCR4. Subsequently, qPCR and Western blotting were performed to determine the effect of miR-193a-5p and chemotherapy drugs on CXCR4. َAlso, MTT assay, and flow cytometry was performed to determine their role in cell viability and apoptosis. Besides, the relationship between miR-193a-5p and CXCR4 with patients' clinical features was investigated. The results of the present study showed that miR-193a-5p was significantly downregulated, whereas CXCR4 was significantly upregulated in tumor tissues obtained from patients with CRC compared with the adjacent non-tumor healthy controls. In addition, the upregulation of miR-193-5p reduced the expression levels of CXCR4, particularly in combination with 5-FU and OX. Besides, using rescue experiments, the present study showed that miR-193a-5p replacement was able to suppress CXCR4-induced CRC cell proliferation by directly targeting CXCR4. Furthermore, there was a significant association between miR-193a-5p and CXCR4 with certain clinicopathological characteristics, particularly with metastasis-related features. These results suggest that miR-193a-5p serves a tumor-suppressive function in CRC and can directly target CXCR4 and decrease its mRNA and protein expression levels. Additionally, miR-193a-5p in combination with 5-FU and Ox potentiated reducing CXR4 expression, which may reveal its contribution to tumor chemoresistance. In conclusion, miR-193-5p may be applicable as a prognostic and diagnostic marker, and also serve as a therapeutic factor by reducing CXCR4 in combination with chemotherapeutic drugs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.intimp.2020.107355DOI Listing
March 2021

Exploring the features of mobile phone application of anatomy in basic medical sciences: a qualitative study.

BMC Med Educ 2020 Jul 20;20(1):231. Epub 2020 Jul 20.

Clinical Education Research Center, Shiraz University of Medical Sciences (SUMS), Shiraz, Iran.

Background: The importance of mobile phones has become one of the new research topics in health professions education due to the ease of access and flexibility. Although novel approaches to health professions education recommend the use of educational technologies, such as mobile applications, a limited number of studies have been conducted with regard to learning anatomy through mobile applications. Considering the increasing needs of medical students for mobile technology to meet their educational needs, wants and desires, we decided to explore the features of an anatomy mobile application.

Methods: This qualitative study was conducted in two stages of holding focus groups, and an expert panel session. Students of basic Medical sciences, and faculty members of anatomy at Iran University of Medical Sciences formed the research participants. Semi-structured interviews and note-taking were used to collect the data. Moreover, Brown and Clark methods were used for thematic analysis. Finally, four criteria presented by Lincoln and Guba for qualitative studies were used to ensure the credibility, confirmability, trustworthiness and transferability of the data.

Results: Based on the data analysis, 37 codes that could be used to design anatomy mobile content for medical students were extracted. These features were categorized into eight main themes of "visual richness", "scientific comprehensiveness", "auditory richness", "affordability", "user-friendliness", "self-assessment", "interactive content" and "user support".

Conclusion: This study explored the features of an anatomy application that can be used by educational app developers. Anatomy departments at Medical Universities, policymakers, and curriculum planners in the field of medical education can also adopt the findings of the present study.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12909-020-02145-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7370475PMC
July 2020

Frequency of Hepatitis C Virus Genotypes in Patients Who Had Hepatocellular Carcinoma in Gastroenterological Hospitals of Tabriz.

J Gastrointest Cancer 2021 Mar;52(1):145-149

Department of Biology Ahar Branch, Islamic Azad University, Ahar, Iran.

Background: Generally, hepatitis C has been identified as one of the major health issues that about 3% of the world's population have been threatened and affected by it (about 170 million people), and also, it can be considered a factor in acute and chronic hepatitis.

Methods: The aim of this study is to determine the prevalence of HCV genotypes in Azerbaijan patients. In this study, sampling was done on the referred patients to the hospitals (Mahallati and Behbud Hospital). RNA was extracted after isolation of plasma, and then, after the synthesizing of cDNA, the sample was carried out to the laboratory for performing the real-time PCR in order to determine the genotypes.

Results: The evaluation of HCV genotypes in positive plasma samples showed that dominant subsets were remarkable and the mean age of the patients was 37/3 ± 11/8 (in the age range of 2-63). Among the 235 patients,139 of them (59%) were male. Statistically, the average number of women was more than men (T test, P < 0/05). 1b genotype was reported 70% in the patients above 40 years old, and also, it was reported as 71/6% in the patients under 40 years old that was not statistically significant. The incidence of serotype 3a was higher among the patients younger than 40 years old (3a was 18.1% vs. 15%), and this serotype was prevalent among men (3a was 18.7% vs. 14.6%), which was statistically significant.

Conclusion: The findings indicate that among Azerbaijan's patients with chronic hepatitis C, genotypes 1b (71.1%) and 3a (17%) were dominant.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s12029-020-00367-2DOI Listing
March 2021

High-resolution genomic screening in mantle cell lymphoma--specific changes correlate with genomic complexity, the proliferation signature and survival.

Genes Chromosomes Cancer 2011 Feb;50(2):113-21

Department of Genetics and Pathology, Uppsala University, Uppsala, Sweden.

Mantle cell lymphoma (MCL) is characterized by the t(11;14)(q13;q32) and numerous copy number aberrations (CNAs). Recently, gene expression profiling defined a proliferation gene expression signature in MCL where high scores predict shorter survival. We investigated 31 MCL cases using high-density single nucleotide polymorphism arrays and correlated CNA patterns with the proliferation signature and with clinical data. Many recurrent CNAs typical of MCL were detected, including losses at 1p (55%), 8p (29%), 9q (29%), 11q (55%), 13q (42%) and 17p (32%), and gains at 3q (39%), 8q (26%), 15q (23%) and 18q (23%). A novel deleted region at 20q (16%) contained only one candidate gene, ZFP64, a putative tumor suppressor. Unsupervised clustering identified subgroups with different patterns of CNAs, including a subset (19%) characterized by the presence of 11q loss in all cases and by the absence of 13q loss, and 3q and 7p gains. Losses at 1p, 8p, 13q and 17p were associated with increased genomic complexity. High proliferation signature scores correlated with increased number of large (>15 Mbp) CNAs (P = 0.03) as well as copy number gains at 7p (P = 0.02) and losses at 9q (P = 0.04). Furthermore, large/complex 13q losses were associated with improved survival (P < 0.05) as were losses/copy number neutral LOH at 19p13 (P = 0.01). In summary, this high-resolution genomic analysis identified novel aberrations and revealed that several CNAs correlated with genomic complexity, the proliferation status and survival.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/gcc.20836DOI Listing
February 2011

Distinct gene expression profiles in subsets of chronic lymphocytic leukemia expressing stereotyped IGHV4-34 B-cell receptors.

Haematologica 2010 Dec 26;95(12):2072-9. Epub 2010 Aug 26.

Department of Genetics and Pathology, Uppsala University, Uppsala, Sweden.

Background: Numerous subsets of patients with chronic lymphocytic leukemia display similar immunoglobulin gene usage with almost identical complementarity determining region 3 sequences. Among IGHV4-34 cases, two such subsets with "stereotyped" B-cell receptors were recently identified, i.e. subset #4 (IGHV4-34/IGKV2-30) and subset #16 (IGHV4-34/IGKV3-20). Subset #4 patients appear to share biological and clinical features, e.g. young age at diagnosis and indolent disease, whereas little is known about subset #16 at a clinical level.

Design And Methods: We investigated the global gene expression pattern in sorted chronic lymphocytic leukemia cells from 25 subset/non-subset IGHV4-34 patients using Affymetrix gene expression arrays.

Results: Although generally few differences were found when comparing subset to non-subset 4/16 IGHV4-34 cases, distinct gene expression profiles were revealed for subset #4 versus subset #16. The differentially expressed genes, predominantly with lower expression in subset #4 patients, are involved in important cell regulatory pathways including cell-cycle control, proliferation and immune response, which may partly explain the low-proliferative disease observed in subset #4 patients.

Conclusions: Our novel data demonstrate distinct gene expression profiles among patients with stereotyped IGHV4-34 B-cell receptors, providing further evidence for biological differences in the pathogenesis of these subsets and underscoring the functional relevance of subset assignment based on B-cell receptor sequence features.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3324/haematol.2010.028639DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2995565PMC
December 2010

Verification that common variation at 2q37.1, 6p25.3, 11q24.1, 15q23, and 19q13.32 influences chronic lymphocytic leukaemia risk.

Br J Haematol 2010 Aug 10;150(4):473-9. Epub 2010 Jun 10.

Section of Cancer Genetics, Institute of Cancer Research, Sutton, Surrey, UK.

A recent genome wide association study of chronic lymphocytic leukaemia (CLL) provided evidence that common variation at 2q13 (rs17483466), 2q37.1 (rs13397985), 6p25.3 (rs872071), 11q24.1 (rs735665), 15q23 (rs7176508) and 19q13.32 (rs11083846) affects CLL risk. To verify and further explore the relationship between these variants and CLL risk we genotyped case-control datasets from Spain and Sweden (824 cases, 850 controls). Combined data provided statistically significant support for an association between genotypes at rs13397985, rs872071, rs735665, rs7176508 and rs11083846 and CLL risk. CLL risk increased with increasing numbers of risk alleles (P(trend) = 1.40 x 10(-15)), consistent with a polygenic model of disease susceptibility. These data validate the relationship between common variation and risk of CLL.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/j.1365-2141.2010.08270.xDOI Listing
August 2010

High-density screening reveals a different spectrum of genomic aberrations in chronic lymphocytic leukemia patients with 'stereotyped' IGHV3-21 and IGHV4-34 B-cell receptors.

Haematologica 2010 Sep 26;95(9):1519-25. Epub 2010 Apr 26.

Department of Genetics and Pathology, Rudbeck Laboratory, Uppsala University, SE-751-85 Uppsala, Sweden.

Background: The existence of multiple subsets of chronic lymphocytic leukemia expressing 'stereotyped' B-cell receptors implies the involvement of antigen(s) in leukemogenesis. Studies also indicate that 'stereotypy' may influence the clinical course of patients with chronic lymphocytic leukemia, for example, in subsets with stereotyped IGHV3-21 and IGHV4-34 B-cell receptors; however, little is known regarding the genomic profile of patients in these subsets.

Design And Methods: We applied 250K single nucleotide polymorphism-arrays to study copy-number aberrations and copy-number neutral loss-of-heterozygosity in patients with stereotyped IGHV3-21 (subset #2, n=29), stereotyped IGHV4-34 (subset #4, n=17; subset #16, n=8) and non-subset #2 IGHV3-21 (n=13) and non-subset #4/16 IGHV4-34 (n=34) patients.

Results: Over 90% of patients in subset #2 and non-subset #2 carried copy-number aberrations, whereas 75-76% of patients in subset #4 and subset #16 showed copy-number aberrations. Subset #2 and non-subset #2 patients also displayed a higher average number of aberrations compared to patients in subset #4. Deletion of 13q was the only known recurrent aberration detected in subset #4 (35%); this aberration was even more frequent in subset #2 (79%). del(11q) was more frequent in subset #2 and non-subset #2 (31% and 23%) patients than in subset #4 and non-subset #4/16 patients. Recurrent copy-number neutral loss-of-heterozygosity was mainly detected on chromosome 13q, independently of B-cell receptor stereotypy.

Conclusions: Genomic aberrations were more common in subset #2 and non-subset #2 than in subset #4. The particularly high frequency of del(11q) in subset #2 may be linked to the adverse outcome reported for patients in this subset. Conversely, the lower prevalence of copy-number aberrations and the absence of poor-prognostic aberrations in subset #4 may reflect an inherently low-proliferative disease, which would prevent accumulation of genomic alterations.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3324/haematol.2009.021014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2930953PMC
September 2010

Common variants at 2q37.3, 8q24.21, 15q21.3 and 16q24.1 influence chronic lymphocytic leukemia risk.

Nat Genet 2010 Feb 10;42(2):132-6. Epub 2010 Jan 10.

Institute of Cancer Research, Sutton, Surrey, UK.

To identify new risk variants for chronic lymphocytic leukemia (CLL), we conducted a genome-wide association study of 299,983 tagging SNPs, with validation in four additional series totaling 2,503 cases and 5,789 controls. We identified four new risk loci for CLL at 2q37.3 (rs757978, FARP2; odds ratio (OR) = 1.39; P = 2.11 x 10(-9)), 8q24.21 (rs2456449; OR = 1.26; P = 7.84 x 10(-10)), 15q21.3 (rs7169431; OR = 1.36; P = 4.74 x 10(-7)) and 16q24.1 (rs305061; OR = 1.22; P = 3.60 x 10(-7)). We also found evidence for risk loci at 15q25.2 (rs783540, CPEB1; OR = 1.18; P = 3.67 x 10(-6)) and 18q21.1 (rs1036935; OR = 1.22; P = 2.28 x 10(-6)). These data provide further evidence for genetic susceptibility to this B-cell hematological malignancy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/ng.510DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5321238PMC
February 2010

IGHV3-21 gene usage is associated with high TCL1 expression in chronic lymphocytic leukemia.

Eur J Haematol 2010 Feb 3;84(2):109-16. Epub 2009 Nov 3.

Dept of Genetics and Pathology, Rudbeck Laboratory, Uppsala University, SE-751 85 Uppsala, Sweden.

T-cell leukemia/lymphoma protein 1 (TCL1) was recently shown to display an expression pattern in chronic lymphocytic leukemia (CLL) corresponding to molecular subtypes, where poor-risk patients demonstrated higher expression levels. Here, we examined the mRNA expression pattern of TCL1 in 144 patients with CLL, including 67 immunoglobulin heavy-chain variable (IGHV) mutated, 58 IGHV unmutated and 19 patients with IGHV3-21 usage. A higher TCL1 expression level was detected in patients with CLL with unmutated vs. mutated IGHV genes (P < 0.001), whereas no difference was demonstrated within the IGHV3-21 cohort (i.e., mutated vs. unmutated and stereotyped vs. non-stereotyped complementarity determining region 3). The IGHV3-21 subgroup displayed high TCL1 mRNA expression, differing significantly from other IGHV mutated cases (P < 0.001), although 11/19 had mutated IGHV genes. Furthermore, high TCL1 expression levels were associated with significantly shorter overall survival (P < 0.001). Altogether, we show that TCL1 mRNA expression may predict clinical outcome in CLL and that the IGHV3-21 subset, regardless of mutational status, displays high TCL1 expression.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/j.1600-0609.2009.01369.xDOI Listing
February 2010

Lipoprotein lipase is differentially expressed in prognostic subsets of chronic lymphocytic leukemia but displays invariably low catalytical activity.

Leuk Res 2010 Mar 25;34(3):301-6. Epub 2009 Aug 25.

Department of Genetics and Pathology, Uppsala University, Uppsala, Sweden.

Lipoprotein lipase (LPL) expression has been shown to correlate with IGHV mutational status and to predict outcome in chronic lymphocytic leukemia (CLL). We here investigated the prognostic impact of LPL expression in relation to other prognostic markers including IGHV3-21 usage in 140 CLL patients. Additionally, we studied the catalytic activity of LPL in CLL cells. A significant difference in LPL mRNA expression was detected in IGHV unmutated compared to mutated CLL patients (p<0.001). However, the poor-prognostic mutated/stereotyped IGHV3-21 patients did not differ from other mutated CLL cases. Clinical outcome was significantly different in CLL cases with high versus low LPL expression (p<0.001), and LPL expression exceeded mutation status/IGHV3-21 usage as an independent prognostic marker. Finally, LPL protein expression correlated significantly with mRNA expression and was higher in IGHV unmutated versus mutated CLL (p=0.018), although the majority of synthesized protein was catalytically inactive indicating a non-catalytical function in CLL.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.leukres.2009.07.032DOI Listing
March 2010

Lack of association between the MDM2 promoter polymorphism SNP309 and clinical outcome in chronic lymphocytic leukemia.

Leuk Res 2010 Mar 1;34(3):335-9. Epub 2009 Jul 1.

Department of Genetics and Pathology, Rudbeck Laboratory, Uppsala University, SE-751 85 Uppsala, Sweden.

The 309T>G polymorphism in the promoter region of the MDM2 gene, known as SNP309, has recently been suggested as an unfavorable prognostic marker in chronic lymphocytic leukemia (CLL) although this has been questioned. To investigate this further, we analyzed the MDM2 SNP309 genotypes in 418 CLL patients and correlated the results with established CLL prognostic factors, time to treatment and overall survival. In this Swedish cohort, no association existed between any particular MDM2 SNP309 genotype, overall survival and time to treatment. Furthermore, no correlation was shown between the MDM2 SNP309 genotypes and Binet stage, IGHV mutational status and recurrent genomic aberrations. In summary, this study argues against the use of the MDM2 SNP309 as a prognostic marker in CLL.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.leukres.2009.06.006DOI Listing
March 2010

Screening for copy number alterations in loci associated with autism spectrum disorders by two-color multiplex ligation-dependent probe amplification.

Am J Med Genet B Neuropsychiatr Genet 2010 Jan;153B(1):280-5

Department of Molecular Medicine and Surgery, Karolinska Institute, Stockholm, Sweden.

The autism spectrum disorder (ASD) is a heterogenous condition characterized by impaired socialization and communication in association with stereotypic behaviors. ASD is highly heritable and heterogeneous with a complex genetic etiology. Recurrent submicroscopic deletions or duplications have been identified in a subgroup of individuals with ASD using array technology. Adequate genetic testing for these genomic imbalances have not yet been widely implemented in the diagnostic setting due to lack of feasible and cost-effective methods as well as difficulties to interpret the clinical significance of these small copy number variants (CNVs). We developed a multiplex ligation-dependent probe amplification (MLPA) assay to investigate its usefulness for detection of copy number alterations (CNAs) in autistic patients. This test proved to be easy to perform, fast, cost-effective, and suitable for reliable detection of multiple loci in a single reaction. We screened 148 autistic patients for 15 different loci covering 26 genes and found a 15q11-13 interstitial duplication that had escaped detection by conventional karyotyping in 1.3% of the patients. Synthetic probe MLPA allows for a flexible analysis of a continuously increasing number of CNAs associated with autism. Our result show that MLPA assay is an easy and cost-effective method for the identification of selected CNAs in diagnostic laboratories.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/ajmg.b.30954DOI Listing
January 2010

A chromosome 10 variant with a 12 Mb inversion [inv(10)(q11.22q21.1)] identical by descent and frequent in the Swedish population.

Am J Med Genet A 2009 Mar;149A(3):380-6

Department of Genetics and Pathology, Uppsala University, Uppsala, Sweden.

We identified a paracentric inversion of chromosome 10 [inv(10)(q11.22q21.1)] in 0.20% of Swedish individuals (15/7,439) referred for cytogenetic analysis. A retrospective analysis of 8,896 karyotypes from amniocenteses in Sweden revealed a carrier frequency of 0.079% (7/8,896) for the inversion. Cloning and detailed analysis of the inversion breakpoint regions show enrichment for interspersed repeat elements and AT-stretches. The centromeric breakpoint coincides with that of a predicted inversion from HapMap data, which suggests that this region is involved in several chromosome 10 variants. No known gene or predicted transcript are disrupted by the inversion which spans approximately 12 Mb. Carriers from four non-related Swedish families have identical inversion breakpoints and haplotype analysis confirmed that the rearrangement is identical by descent. Diagnosis was retrieved in 6 out of the 15 carriers referred for cytogenetic analysis. No consistent phenotype was found to be associated with the inversion. Our study demonstrates that the inv(10)(q11.22q21.1) is a rare and inherited chromosome variant with a broad geographical distribution in Sweden.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/ajmg.a.32663DOI Listing
March 2009

Alterations in the expression, structure and function of progesterone receptor membrane component-1 (PGRMC1) in premature ovarian failure.

Hum Mol Genet 2008 Dec 9;17(23):3776-83. Epub 2008 Sep 9.

Department of Genetics and Pathology, Uppsala University, Uppsala, Sweden.

Premature ovarian failure (POF) is characterized by hypergonadotropic hypogonadism and amenorrhea before the age of 40. The condition has a heterogeneous background but genetic factors are demonstrated by the occurrence of familial cases. We identified a mother and daughter with POF both of whom carry an X;autosome translocation [t(X;11)(q24;q13)]. RNA expression studies of genes flanking the X-chromosome breakpoint revealed that both patients have reduced expression levels of the gene Progesterone Receptor Membrane Component-1 (PGRMC1). Mutation screening of 67 females with idiopathic POF identified a third patient with a missense mutation (H165R) located in the cytochrome b5 domain of PGRMC1. PGRMC1 mediates the anti-apoptotic action of progesterone in ovarian cells and it acts as a positive regulator of several cytochrome P450 (CYP)-catalyzed reactions. The CYPs are critical for intracellular sterol metabolism, including biosynthesis of steroid hormones. We show that the H165R mutation associated with POF abolishes the binding of cytochrome P450 7A1 (CYP7A1) to PGRMC1. In addition, the missense mutation attenuates PGRMC1's ability to mediate the anti-apoptotic action of progesterone in ovarian cells. These findings suggest that mutant or reduced levels of PGMRC1 may cause POF through impaired activation of the microsomal cytochrome P450 and increased apoptosis of ovarian cells.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/hmg/ddn274DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2722898PMC
December 2008

Screening for copy-number alterations and loss of heterozygosity in chronic lymphocytic leukemia--a comparative study of four differently designed, high resolution microarray platforms.

Genes Chromosomes Cancer 2008 Aug;47(8):697-711

Lund Strategic Research Center for Stem Cell Biology and Cell Therapy, Hematology and Transplantation, Lund University, Lund, Sweden.

Screening for gene copy-number alterations (CNAs) has improved by applying genome-wide microarrays, where SNP arrays also allow analysis of loss of heterozygozity (LOH). We here analyzed 10 chronic lymphocytic leukemia (CLL) samples using four different high-resolution platforms: BAC arrays (32K), oligonucleotide arrays (185K, Agilent), and two SNP arrays (250K, Affymetrix and 317K, Illumina). Cross-platform comparison revealed 29 concordantly detected CNAs, including known recurrent alterations, which confirmed that all platforms are powerful tools when screening for large aberrations. However, detection of 32 additional regions present in 2-3 platforms illustrated a discrepancy in detection of small CNAs, which often involved reported copy-number variations. LOH analysis using dChip revealed concordance of mainly large regions, but showed numerous, small nonoverlapping regions and LOH escaping detection. Evaluation of baseline variation and copy-number ratio response showed the best performance for the Agilent platform and confirmed the robustness of BAC arrays. Accordingly, these platforms demonstrated a higher degree of platform-specific CNAs. The SNP arrays displayed higher technical variation, although this was compensated by high density of elements. Affymetrix detected a higher degree of CNAs compared to Illumina, while the latter showed a lower noise level and higher detection rate in the LOH analysis. Large-scale studies of genomic aberrations are now feasible, but new tools for LOH analysis are requested.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/gcc.20575DOI Listing
August 2008

Molecular genetic analysis of a de novo balanced translocation t(6;17)(p21.31;q11.2) associated with hypospadias and anorectal malformation.

Hum Genet 2006 Mar 3;119(1-2):162-8. Epub 2006 Jan 3.

Department of genetics and pathology, Section of Clinical Genetics The Rudbeck laboratory, Uppsala University, 751 85 Uppsala, Sweden.

We report a young boy with penoscrotal hypospadias, anal atresia (AA) with a recto-urethral fistula, a hypoplastic kidney and a balanced translocation t(6;17)(p21.31;q11.2). Physical mapping of the breakpoints localized the chromosome 6 breakpoint within an intron of the gene lipoma HMGIC fusion partner-like 5 (LHFPL5) whereas the chromosome 17 breakpoint was mapped to the first intron of the 182-FIP gene encoding the Fragile X Mental Retardation Protein Interacting Protein. Sequence analysis across the breakpoints revealed an almost perfectly balanced translocation with a 2 bp deletion on the derivative chromosome 6 and a 7 bp duplication on the derivative chromosome 17. We identified a fusion transcript consisting of the first exon of 182-FIP and the last exon of LHFPL5 in patient-derived cells. Quantitative expression analysis of the genes flanking the breakpoints, revealed increased transcript levels for SFRS protein kinase 1 (SRPK1) and TAO kinase 1 (TAOK1) which suggests a positional effect due to the translocation. We hypothesize that the urogenital and anorectal malformations in the patient result from one or several mechanisms including disruption of the genes 182-FIP and LHFPL5, altered expression of the genes flanking the translocation breakpoints and, a gain of function mechanism mediated by the 182-FIP-LHFPL5 fusion transcript.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00439-005-0122-9DOI Listing
March 2006

Loss of ZDHHC15 expression in a woman with a balanced translocation t(X;15)(q13.3;cen) and severe mental retardation.

Eur J Hum Genet 2005 Aug;13(8):970-7

Department of Genetics and Pathology, Uppsala University, Sweden.

X-linked mental retardation (XLMR) affects one in 600 males and is highly heterogeneous. We describe here a 29-year-old woman with severe nonsyndromic mental retardation and a balanced reciprocal translocation between chromosomes X and 15 [46,XX,t(X;15)(q13.3;cen)]. Methylation studies showed a 100% skewed X-inactivation in patient-derived lymphocytes indicating that the normal chromosome X is retained inactive. Physical mapping of the breakpoints localised the Xq13.3 breakpoint to within 3.9 kb of the first exon of the ZDHHC15 gene encoding a zinc-finger and a DHHC domain containing product. Expression analysis revealed that different transcript variants of the gene are expressed in brain. ZDHHC15-specific RT-PCR analysis on lymphocytes from the patient revealed an absence of ZDHHC15 transcript variants, detected in control samples. We suggest that the absence of the ZDHHC15 transcripts in this patient contributes to her phenotype, and that the gene is a strong candidate for nonsyndromic XLMR.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/sj.ejhg.5201445DOI Listing
August 2005