New molecular biology methods have specified the evidence of chromosomal changes in the tumor tissue. These alterations can be proven to exist in the majority of malignant tumors. The fast progress of whole genome molecular biological methods has helped to improve the knowledge of tumor genetics. The evidence of genetic changes is a component of currently used diagnostic and prognostic schemes in particular cancer diseases. Karyotyping was the first method used in the clinical practice but its importance has decreased with the arrival of new molecular biological methods. The most common methods used for the detection of chromosomal deletions or amplifications are CGH, array-CGH and SNP array. The first two methods are based on the principle of comparison between tumor DNA and control DNA. The principle of SNP array uses the presence of single nucleotide polymorphisms that are located in the whole genome in each individual. SNP array can prove not only deletions or amplifications of the chromosomes but unlike CGH techniques it can also detect a loss of heterozygosity or uniparental disomy. The screening of chromosomal changes has nowadays become routine. These techniques are used for diagnosis, prognosis and treatment of cancer disease in certain cases.
- MeSH
- Chromosome Aberrations MeSH
- DNA, Neoplasm analysis genetics MeSH
- Polymorphism, Single Nucleotide genetics MeSH
- Humans MeSH
- Neoplasms diagnosis genetics MeSH
- Oligonucleotide Array Sequence Analysis methods MeSH
- Comparative Genomic Hybridization methods MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
- Names of Substances
- DNA, Neoplasm MeSH
Alterations in the genome that lead to changes in DNA sequence copy number are characteristic features of solid tumors. We used CGH+SNP microarray and HPV-FISH techniques for detailed screening of copy number alterations (CNAs) in a cohort of 26 patients with cervical carcinoma (CC). This approach identified CNAs in 96.2% (25/26) of tumors. Array-CGH discovered CNAs in 73.1% (19/26) of samples, HPV-FISH experiments revealed CNAs in additional 23.1% (6/26) of samples. Common gains of genetic sequences were observed in 3q (50.0%), 1q (42.4%), 19q (23.1%), while losses were frequently found in 11q (30.8%), 4q (23.1%) and 13q (19.2%). Chromosomal regions involved in loss of heterozygosity were observed in 15.4% of samples in 8q21, 11q23, 14q21 and 18q12.2. Incidence of gain 3q was associated with HPV 16 and HPV 18 positive samples and simultaneous presence of gain 1q (P = 0.033). We did not found a correlation between incidence of CNAs identified by array-CGH and HPV strain infection and incidence of lymph node metastases. Subsequently, HPV-FISH was used for validation of array-CGH results in 23 patients for incidence of hTERC (3q26) and MYC (8q24) amplification. Using HPV-FISH, we found chromosomal lesions of hTERC in 87.0% and MYC in 65.2% of specimens. Our findings confirmed the important role of HPV infection and specific genomic alterations in the development of invasive cervical cancer. This study also indicates that CGH+SNP microarrays allow detecting genome-wide CNAs and copy-neutral loss of heterozygosity more precisely, however, it may be less sensitive than FISH in samples with low level clonal CNAs.
- Keywords
- CGH+SNP microarrays, Cervical carcinoma, HPV-FISH, copy number alterations, whole-genome profiling,
- MeSH
- Adult MeSH
- In Situ Hybridization, Fluorescence MeSH
- Papillomavirus Infections complications genetics MeSH
- Carcinoma genetics virology MeSH
- Middle Aged MeSH
- Humans MeSH
- Uterine Cervical Neoplasms genetics virology MeSH
- Oligonucleotide Array Sequence Analysis methods MeSH
- Aged MeSH
- Sensitivity and Specificity MeSH
- Comparative Genomic Hybridization methods MeSH
- Gene Expression Profiling methods MeSH
- DNA Copy Number Variations MeSH
- Loss of Heterozygosity genetics MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
BACKGROUND: Both high hyperdiploidy (HeH) and the translocation t(9;22)(q34;q11) are recurrent abnormalities in childhood B-cell acute lymphoblastic leukemia (ALL) and both are used in current classification to define different genetic and prognostic subtypes of the disease. The coexistence of these two primary genetic aberrations within the same clone is very rare in children with ALL. Here we report a new case of a 17-year-old girl with newly diagnosed ALL and uncommon cytogenetic and clinical finding combining high hyperdiploidy and a cryptic BCR/ABL1 fusion and an inherited Charcot-Marie-Tooth neuropathy detected during the induction treatment. RESULTS: High hyperdiploid karyotype 51,XX,+X,+4,+14,+17,+21 without apparent structural aberrations was detected by conventional cytogenetic analysis and multicolor FISH. A cryptic BCR/ABL1 fusion, which was caused by the insertion of part of the ABL1 gene into the 22q11 region, was proved in HeH clone by FISH, RT-PCR and CGH-SNP array. In addition, an abnormal FISH pattern previously described as the deletion of the 3'BCR region in some BCR/ABL1 positive cases was not proved in our patient. CONCLUSION: A novel case of extremely rare childhood ALL, characterized by HeH and a cryptic BCR/ABL1 fusion, is presented and to the best of our knowledge described for the first time. The insertion of ABL1 into the BCR region in malignant cells is supposed. Clearly, further studies are needed to determine the genetic consequences and prognostic implications of these unusual cases.
- Keywords
- BCR/ABL1 fusion, CGH–SNP array, FISH, High-hyperdiploid childhood ALL, Ph-negative childhood ALL,
- Publication type
- Journal Article MeSH
- Case Reports MeSH
Chromosome 17q21.31 microdeletion syndrome is a genomic disorder caused by a recurrent 600 kb long deletion. The deletion affects the region of a common inversion present in about 20% of Europeans. The inversion is associated with the H2 haplotype carrying additional low-copy repeats susceptible to non-allelic homologous recombination, and this haplotype is prone to deletion. No instances of 17q21.31 deletions inherited from an affected parent have been reported, and the deletions always affected a parental chromosome with the H2 haplotype. The syndrome is characterized clinically by intellectual disability, hypotonia, friendly behavior and specific facial dysmorphism with long face, large tubular or pear-shaped nose and bulbous nasal tip. We present monozygotic twin sisters showing the typical clinical picture of the syndrome. The phenotype of the sisters was very similar, with a slightly more severe presentation in Twin B. The 17q21.31 microdeletion was confirmed in both patients but in neither of their parents. Potential copy number differences between the genomes of the twins were subsequently searched using high-resolution single nucleotide polymorphism (SNP) and comparative genome hybridisation (CGH) arrays. However, these analyses identified no additional aberrations or genomic differences that could potentially be responsible for the subtle phenotypic differences. These could possibly be related to the more severe perinatal history of Twin B, or to the variable expressivity of the disorder. In accord with the expectations, one of the parents (the mother) was shown to carry the H2 haplotype, and the maternal allele of chromosome 17q21.31 was missing in the twins.
- MeSH
- Chromosome Deletion MeSH
- Adult MeSH
- Twins, Monozygotic genetics MeSH
- Haplotypes * MeSH
- Polymorphism, Single Nucleotide * MeSH
- Humans MeSH
- Chromosomes, Human, Pair 17 genetics MeSH
- Intellectual Disability genetics pathology MeSH
- Smith-Magenis Syndrome MeSH
- Check Tag
- Adult MeSH
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Case Reports MeSH
- Research Support, Non-U.S. Gov't MeSH
- Twin Study MeSH
BACKGROUND: Constitutional translocations between sex chromosomes are rather rare in humans with breakpoints at Xp11 and Yq11 as the most frequent. Breakpoints on the short arm of the Y chromosome form one subgroup of t(X;Y), giving rise to a derived chromosome with the centromeres of both the X and Y chromosomes, dic(X;Y). Here, we report a rare congenital chromosomal aberration, 46,X,dic(X;Y)(p22.33;p11.32)[20]/45,X[10], in an adult male. CASE PRESENTATION: Primary myelofibrosis, a malignant haematological disease, was diagnosed in a 63-year-old man following liver transplantation after hepatocellular carcinoma. By the analysis of the bone marrow sample, the karyotype 46,X,dic(X;Y)(p22.33;p11.32) was detected in all the mitoses analysed and verified with multicolour fluorescence in situ hybridization (mFISH). A cytogenetic examination of stimulated peripheral blood cells revealed the constitutional karyotype 46,X,dic(X;Y)(p22.33;p11.32)[20]/45,X[10]. The cell line 45,X was confirmed with FISH in 35 % of interphase nuclei. The SRY locus was present on the dicentric chromosome. A CGH/SNP array (Illumina) revealed a gain of 153,7 Mbp of the X chromosome and a 803-kbp microdeletion (including the SHOX gene), which were also confirmed with FISH. SHOX encodes a transcriptional factor that regulates the growth of the long bones. The deletion of the SHOX gene together with the Madelung deformity of the forearm and the short stature of the proband led to a diagnosis of Léri-Weill dyschondrosteosis (LWD). The gain of almost the whole X chromosome (153,7 Mbp) was considered a variant of Klinefelter syndrome (KS). The levels of gonadotropins and testosterone were consistent with gonadal dysfunction. A malformation of the right external ear was detected. CONCLUSIONS: We have reported a structural aberration of the sex chromosomes, dic(X;Y)(p22.33;p11.32). The related genomic imbalance is associated with two known hereditary syndromes, LWD and a KS variant, identified in our proband at an advanced age. Because the breakpoints did not involve cancer genes, we inferred that the two malignancies in the proband were not caused by this abnormality. The possible influence of SHOX haploinsufficiency on the growth regulation of auricular chondrocytes is discussed.
- Keywords
- Klinefelter syndrome variant, Léri-Weill dyschondrosteosis, dic(X;Y)(p22.33;p11.32),
- Publication type
- Journal Article MeSH
- Case Reports MeSH
Arowanas (Osteoglossinae) are charismatic freshwater fishes with six species and two genera (Osteoglossum and Scleropages) distributed in South America, Asia, and Australia. In an attempt to provide a better assessment of the processes shaping their evolution, we employed a set of cytogenetic and genomic approaches, including i) molecular cytogenetic analyses using C- and CMA3/DAPI staining, repetitive DNA mapping, comparative genomic hybridization (CGH), and Zoo-FISH, along with ii) the genotypic analyses of single nucleotide polymorphisms (SNPs) generated by diversity array technology sequencing (DArTseq). We observed diploid chromosome numbers of 2n = 56 and 54 in O. bicirrhosum and O. ferreirai, respectively, and 2n = 50 in S. formosus, while S. jardinii and S. leichardti presented 2n = 48 and 44, respectively. A time-calibrated phylogenetic tree revealed that Osteoglossum and Scleropages divergence occurred approximately 50 million years ago (MYA), at the time of the final separation of Australia and South America (with Antarctica). Asian S. formosus and Australian Scleropages diverged about 35.5 MYA, substantially after the latest terrestrial connection between Australia and Southeast Asia through the Indian plate movement. Our combined data provided a comprehensive perspective of the cytogenomic diversity and evolution of arowana species on a timescale.
- Keywords
- DArTseq, Gondwana, biogeography, evolution, genetic diversity,
- MeSH
- Principal Component Analysis MeSH
- Biological Evolution * MeSH
- Genetic Variation MeSH
- Genomics * MeSH
- Genotyping Techniques MeSH
- Karyotype MeSH
- Chromosome Mapping MeSH
- Chromosome Banding MeSH
- Fishes genetics MeSH
- Geography MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Comparative Study MeSH
