Current update on molecular cytogenetics, diagnosis and management of gastrointestinal stromal tumors

Gastrointestinal stromal tumors(GISTs)are the most common mesenchymal tumors of the gastrointestinal(GI)tract and are thought to arise from precursors of the interstitial cells of Cajal.GISTs can arise anywhere in the GI tract,but most commonly originate from the stomach and small intestine.The majority of GISTs occur as a result of activating mutations in two receptor protein tyrosine kinases:KIT and/or platelet-derived growth factor receptor-α.Mutational analyses allow for predicting patient prognosis and treatment response.Clinical presentations can vary from no symptoms,typical in the case of small incidentally found tumors,to GI bleeding,abdominal discomfort,and ulcer-related symptoms when the tumor is enlarged.Imaging plays a critical role in the diagnosis and management of these tumors with multiphasic computed tomography serving as the imaging modality of choice.Magnetic resonance imaging and positron emission tomography-computed tomography can serve as imaging adjuncts in lesion characterization,especially with liver metastases,and subsequent staging and assessment for treatment response or recurrence.Surgical resection is the preferred management for small GISTs,while tyrosine kinase inhibitors−imatinib mesylate and sunitinib malate−serve as crucial molecular-targeted therapies for locally advanced and metastatic GISTs.This review article highlights the clinical presentation,pathology and molecular cytogenetics,imaging features,and current management of GISTs.

Detection of Cytogenetic Effects in Peripheral Lymphocytes of Students Exposed to Formaldehyde with Cytokinesis-Blocked Micronucleus Assay

Cytokinesis-blocked micronucleus assay was applied as a biological dosimeter to detect abnormalities in human peripheral lymphocytes of thirteen students exposed to formaldehyde (FA) during a 12-week (10 h per week) anatomy class. Breathing-zone air samples colleeted during dissection procedures showed a mean concentration of 2. 37 ppm (3. 17mg/m3 ). Ten students from the same school but without FA exposure served as controls. Chromosome aberrations (CA) and sister chromatid exchanges (SCE) were detected in both groups. The micronuclei (MN) rate (6. 38 ± 2. 50‰ ) and CA rate (5. 92 ±2. 40‰ ) in the FA-exposed group showed a significant increase (P< 0. 01 ) when compared with those of the controls (3. 15 ±1. 46‰and 3. 40 ± 1. 57 % respectively). A correlation between MN and CA in individuals was observed. SCE in the exmpd group were also increased (P< 0. 05), but not so greatly as MN or CA. The results indicated that FA might damage the chromosomes of human lymphocytes.

Cytogenetic Mapping of Disease Resistance Genes and Analysis of Their Distribution Features on Chromosomes in Maize

Cytogenetic maps of four clusters of disease resistance genes were generated by ISH of the two RFLP markers tightly linked to and flanking each of maize resistance genes and the cloned resistance genes from other plant species onto maize chromosomes, combining with data published before. These genes include Helminthosporium turcium Pass resistance genes Ht1, Htn1 and Ht2, Helminthosporium maydis Nisik resistance genes Rhm1 and Rhm2, maize dwarf mosaic virus resistance gene Mdm1, wheat streak mosaic virus resistance gene Wsm1, Helminthosporium carbonum ULLstrup resistance gene Hml and the cloned Xanthomonas oryzae pv. Oryzae resistance gene Xa21 of rice, Cladosporium fulvum resistance genes Cf-9 and Cf-2.1 of tomato,and Pseudomonas syringae resistance gene RPS2 of Arabidopsis. Most of the tested disease resistance genes located on the four chromosomes, i.e., chromosomes1, 3, 6 and 8, and they closely distributed at the interstitial regions of these chromosomal long arms with percentage distances ranging 31.44(±3.72)-72.40(±3.25) except for genes Rhm1, Rhm2, Mdm1 and Wsm1 which mapped on the satellites of the short arms of chromosome6. It showed that the tested RFLP markers and genes were duplicated or triplicated in maize genome. Homology and conservation of disease resistance genes among species, and relationship between distribution features and functions of the genes were discussed. The results provide important scientific basis for deeply understanding structure and function of disease resistance genes and breeding in maize.

Cytogenetic Mechanism for the Aneuploidy and Mosaicism Foundin Tetraploid Pacific Oyster Crassostrea gigas （Thunberg）

Chromosome constitution was investigated in adult tetraploid Pacific oyster produced by blocking the first polar body oftriploid eggs which were fertilized with haploid sperms. A high incidence of aneuploid and heteroploid mosaics were found amongthe offspring. Of 20 individuals identified, only 9 （45%） were eutetraploid which contained 40 chromosomes; 2 （10%） were ane-uploid （hypotetraploid）, which contained 39 and 38 chromosomes, respectively; and 9 （45%） were heteroploid mosaics. One mosaicwas consisted of cells containing 40 and 39 chromosomes, respectiovely （1：1 in cell number）, while the other 8 were consisted ofcells containing chromosomes varying between tetraploid and triploid. It was also interesting to note that 3 mosaics even containedsome diploid cells with 20 chromosomes. A certain number of cells of 2 tetraploids and 8 mosaics spread with 32-37 well-scatteredand some clumped chromosomes at metaphase. The percentage of aneuploid cells with chromosomes varying between triploid andtetraploid correlated significantly with that of heteroploid mosaics cells with clumping chromosomes （P〈0.05）. Our findings sug-gested that reversion existed in both tetraploid and triploid oyster and chromosome clumping may underline the chromosome elimi-nation in tetraploid oyster. It seems that the reversing cells, at least some of them, continuously eliminate their chromosomes until themost stable diploid state is established.

Comparison of Mitoxantrone in Combination with Intermediate-dose Cytarabine versus High-dose Cytarabine as Consolidation Therapies for Young Non-APL Acute Myeloid Leukemia Patients with Favorable and Intermediate Cytogenetics

In this study,we compared the efficacy of mitoxantrone in combination with intermediate-dose cytarabine（HAM） with that of high-dose cytarabine alone（Hi DAC） as consolidation regimens in non-acute promyelocytic leukemia（APL） acute myeloid leukemia patients with favorable and intermediate cytogenetics.A total of 62 patients from Shenzhen People＇s Hospital were enrolled in this study.All patients enrolled received standard induction chemotherapy and achieved the first complete remission（CR1）.In these patients,24 received Hi DAC and 38 received HAM as consolidation.The median relapse free survival（RFS） and overall survival（OS） were similar between these two consolidation regimens.Even in subgroup analysis according to risk stratification,the combination regimen conferred no benefit in longterm outcome in patients with favorable or intermediate cytogenetics.However,in patients receiving HAM regimen,the lowest neutrophil count was lower,neutropenic period longer,neutropenic fever rate higher,and more platelet transfusion support was required.HAM group also tended to have higher rate of sepsis than Hi DAC group.According to our results,we suggest that combination treatment with mitoxantrone and intermediate-dose cytarabine has limited value as compared to Hi DAC,even in young non-APL AML patients with favorable and intermediate cytogenetics.

The Biodiversity of Shrimp Genus Artemia from Russian Lakes:Morphometric,Cytogenetics and DNA-analysis

Shrimps of genus Artemia are the inhabitants of continental and marine waters with salinity of 70 to 350 g/l and above.Artemia is able to survive in the conditions in which other animals cannot exist.This is due to adaptations:effective osmoregulation system,the ability to synthesize of respiratory pigment(hemoglobin)and diapauses cysts(Litvinenko at.al.,2009).Cysts of this

Cytogenetics and germplasm enrichment in Brassica allopolyploids in China

This paper reviews research advances in cytogenetics and germplasm innovation in Brassica allopolyploids, particularly oilseed rape（Brassica napus）, in China. Three naturally evolved Brassica allotetraploid species are cytologically stable but tend to preferentially lose several chromosomes from one subgenome when induced by alien chromosome elimination. A-subgenome is extracted from B. napus, and the ancestral Brassica rapa was restituted after the total loss of C-subgenome chromosomes. Genome-wide genetic and epigenetic alterations were observed in both natural and synthetic Brassica allotetraploids. B. napus was subjected to extensive interspecific hybridization with landraces of B. rapa and Brassica juncea, which exhibit abundant phenotype variations, to widen the genetic diversity in breeding and select numerous elite germplasm resources and cultivars; these cultivars include the representative Zhongyou 821, which also parented numerous other varieties. Novel B. napus genotypes were obtained using Brassica trigenomic hybrids and allohexaploids（2 n=54, AABBCC） by combining subgenomes from extant allotetraploids and diploids as bridge. Alien additions, substitutions, and translocations of the B. napus genome were developed by intergeneric/intertribal sexual and somatic hybridizations with several crucifers. Furthermore, mitochondrial DNA recombination promoted the production of novel cytoplasmic male sterile lines.

Mosaic Trisomy 21 and Trisomy 14 as Acquired Cytogenetic Abnormalities without GATA1 Mutation in A Pediatric Non-Down Syndrome Acute Megakaryoblastic Leukemia

One case of acute megakaryoblastic leukemia （AMKL） with trisomy 21,trisomy 14 and unmutated GATA1 gene in a phenotypically normal girl was reported.The patient experienced transient myelodysplasia before the onset of AMKL.The bone marrow blasts manifested typical morphology of megakaryoblast both by the May-Giemsa staining and under the electronic microscopy.Leukemic cells were positive for CD13,CD33,CD117,CD56,CD38,CD41 and CD61 in flow cytometry analysis.Cytogenetic study showed karyotype of 48,XX,＋14,＋21 in 40% metaphases.Known mutations of GATA1 gene in Down syndrome or acquired trisomy 21 were not detected in this case.

CYTOGENETIC STUDY ON A NEW EPITHELIAL CELL LINE, HNE-1,DERIVED FROM NASOPHARYNGEAL CARCINOMA

The cytogenetics of HNE- 1 cell line derived from the biopsy of nasopharyngeal carcinoma of a 27- year- old Chinese male has been investigated by chromosomal banding technique. A karyotypic characterization of subteraploid and a modal number of 74 - 77 have been revealed in this cell line. All cells contained a series of non- random chromosomal rearrangements. 18 of them, including 5 isochromosomes. were present in all metaphases and 3 of them in a few one. These findings indicated that the severe DNA damage and increase of gene copies may be occurred in genome of HNE- 1 cells.

Past and recent advances in sugarcane cytogenetics

The Saccharum genus comprises species with large and variable chromosome numbers, leading to challenges in genomic studies and breeding improvement. Cytogenetics, including classical and molecular approaches, has played a central role in deciphering the genome structure, classification, and evolution of the genus Saccharum. The application of fluorescence in situ hybridization using oligonucleotide probes significantly improved our understanding of the complex genomes of Saccharum species. This paper reviews the application and progress of cytogenetic techniques in Saccharum. Future applications of cytogenetics are discussed, as they could benefit both genomic studies and breeding of sugarcane as well as other plants with complex genomes.

Diversity of reptile sex chromosome evolution revealed by cytogenetic and linked-read sequencing

Reptile sex determination is attracting much attention because the great diversity of sex-determination and dosage compensation mechanisms permits us to approach fundamental questions about mechanisms of sex chromosome turnover. Recent studies have made significant progress in better understanding diversity and conservation of reptile sex chromosomes, with however no reptile master sex determination genes identified. Here we describe an integrated genomics and cytogenetics pipeline,combining probes generated from the microdissected sex chromosomes with transcriptome and genome sequencing to explore the sex chromosome diversity in non-model Australian reptiles. We tested our pipeline on a turtle, two species of geckos, and a monitor lizard. Genes identified on sex chromosomes were compared to the chicken genome to identify homologous regions among the four species. We identified candidate sex determining genes within these regions, including conserved vertebrate sex-determining genes pdgfa,pdgfra amh and wt1, and demonstrated their testis or ovary-specific expression. All four species showed gene-by-gene rather than chromosome-wide dosage compensation. Our results imply that reptile sex chromosomes originated by independent acquisition of sex-determining genes on different autosomes,as well as translocations between different ancestral macro-and microchromosomes.We discuss the evolutionary drivers of the slow differentiation and turnover of reptile sex chromosomes.

Clinical cytogenetics and molecular cytogenetics

The short report will be focused on helping our students to understand commonly used conventional and cutting edge cytogenetic techniques and their clinical applications, the advances and drawbacks of each technique, and how to pick the right test(s) for a specific patient in order to achieve a proper diagnosis efficiently and economically.

Cytogenetic Characteristics of Childhood Acute Lymphoblastic Leukemia:A Study of 1541 Chinese Patients Newly Diagnosed between 2001 and 2014

Objective:Cytogenetic abnormalities have been proven to be the most valuable parameter for risk stratification of childhood acute lymphoblastic leukemia(ALL).However,studies on the prevalence of cytogenetic abnormalities and their correlation to clinical features in Chinese pediatric patients are limited,especially large-scale studies.Methods:We collected the cytogenetics and clinical data of 1541 children newly diagnosed with ALL between 2001 and 2014 in four Chinese hospitals,and retrospectively analyzed their clinical features,prognosis and risk factors associated with pediatric ALL.

Identification and characterization of cell cultures with various embryogenic/regenerative potential in cotton based on morphological,cytochemical,and cytogenetical assessment

Somatic embryogenesis(SE) plays a vital role in genetic transformation and massive propagation of important agronomical and economical crops.Here,we conducted a systematic assessment of the morphological,cytochemical,and cytogenetical characteristics of six culture strains with various embryogenic/regenerative potential during SE process in cotton.Results indicated that the six cell culture strains had stable ploidy levels,and did not reveal any relationship between the cytogenetic state and their morphogenetic potential.Moreover,the six culture strains were compared via double staining with Evans blue and Acetocarmine to efficiently distinguish embryogenic and non-embryogenic cells and determine the embryogenic nature of the calli.In addition,the kind of auxins added in medium affected not only growth property,color,size of cell clumps but also ploidy level and regeneration ability.By combining analysis of morphological,cytochemical,and cytogenetical characteristics of the cell cultures,we are able to obtain and maintain homogeneous cell population with high morphogenic and regeneration ability and establish efficient somatic embryogenesis and regeneration system from short-term cell cultures in upland cotton,which highlight the application of biotechnological approaches in crop breeding,and above all,to better understand totipotency of cells in higher plants.

Molecular Cytogenetic Analysis of Spontaneous Interspecific Hybrid Between Oryza sativa and Oryza minuta

Genomic in situ hybridization (GISH) is a powerful tool to characterize parental chromosomes in interspecific hybrids, including the behaviour of autosynapsis and chromosome pairing. It was used to distinguish the chromosomes of Oryza sativa from wild species in a spontaneous interspecific hybrid and to investigate the chromosome pairing at metaphase I in meiosis of the hybrid in this study. The hybrid was a triploid with 36 chromosomes according to the chromosome number investigated in mitosis of root tips. During metaphase I of meiosis in the hybrid, less chromosome pairing was observed and most of the chromosomes existed as univalent. Based on GISH and FISH (Fluorescent in situ hybridization) analyses, the chromosomes of the hybrid were composed of genomes A, B and C. Thus, it was believed that the hybrid was the result of natural hybridization between cultivated rice and wild species O. minuta which was planted in experimental fields.

CLASSIFICATION OF NINETY-EIGHT ADULT CASES OF ACUTE LEUKEMIAS ACCORDING TO MORPHOLOGY,IMMUNOLOGY AND CYTOGENETICS

In the present study, 98 cases of acute leukemias (AL) were diagnosed and classified based on morphologic, immunologic and cytogenetic (MIC) features to assess their diagnostic value in AL. The results showed that: the conformity rate of cytomorphologic/cytochemical classification with MIC classification was 90.8%. For ALL, the conformity rate of immunologic classification with MIC classification was 95.6% while it was only 70.8% for AML. Of the 48 AML, 10 expressed lymphoid-lineage-associated antigens and 8 of 43 ALL expressed myeloid-lineage-associated antigens. Seven cases were diagnosed as hybrid acute leukemia according to Catovsky's scoring criterion. The clonal chromosomal aberrations were found in 70 cases, of them 46 cases showed characteristic changes including t(9; 22), t(4; 11), t(11; 14), t(8; 12), t(8; 14), 6q-, 9p- and t(15; 17), t(8; 21), inv(16), etc. These data suggested that MIC classification of acute leukemias could provide more diagnostic and biologic information than traditional FAB classification.

Complete Cytogenetic Insight of Tho-Tho Cattle

To investigate the cytogenetic parameters and characterise the chromosomal banding pattern of Tho-Tho cattle, a breed of indigenous cattle found in the Northeastern states of India were reared for meat purpose. Lymphocyte culture technique was carried out in 28 Tho-Tho cattle and culture was harvested for good metaphase spread. Good metaphase spreads were selected for analysis, such as relative length, centromeric index and arm ratio. Centromeric banding （C-banding） and reverse banding （R-banding） methods were done for detail and better understanding of the chromosome morphology. The chromosome number in Tho-Tho cattle was observed to be 2n = 60 in all complete metaphase. The mean relative length of the autosomal chromosomes varied from 5.48% ：~ 0.107% to 1.79% ＋ 0.105% in male and 5.31% ：E 0.148% to 1.86% ＋ 0.055% in female, respectively. The chromosome banding showed C-positive dark band heterochromatin in all the acrocentric autosome. However, in sex chromosome, the Y-chromosome showed negative C-band and also the X-chromosome did not show any stain at the centromeric region. The numbers of R-band pattern were observed to be 490 and 499 band in male and female, respectively. One of the X-chromosome showed light banding pattern, confirming the inactivation during the embryonic development in female. The fundamental chromosome number and banding pattern of Tho-Tho cattle did not vary from the other breed of the Bos indicus. However, it is necessary to start a cytogenetic screening of the Tho-Tho cattle and expand upon more number to be kept at different villages of Nagaland in order to identify animals with chromosomal abnormalities, so that it can be excluded from future breeding strategies for conservation of Tho-Tho genetic resource.

Integrated analysis of comorbidity, pregnant outcomes, and amniotic fluid cytogenetics of fetuses with persistent left superior vena cava

BACKGROUND Persistent left superior vena cava(PLSVC)is the most common venous system variant.The clinical characteristics and amniotic fluid cytogenetics of fetuses with PLSVC remain to be further explored.AIM To develop reliable prenatal diagnostic recommendations through integrated analysis of the clinical characteristics of fetuses with PLSVC.METHODS Cases of PLSVC diagnosed using prenatal ultrasonography between September 2019 and November 2022 were retrospectively studied.The clinical characteristics of the pregnant women,ultrasonic imaging information,gestational age at diagnosis,pregnancy outcomes,and amniocentesis results were summarized and analyzed using categorical statistics and the chi-square test or Fisher’s exact test.RESULTS Of the 97 cases diagnosed by prenatal ultrasound,49(50.5%)had isolated PLSVC and 48(49.5%)had other structural abnormalities.The differences in pregnancy outcomes and amniocentesis conditions between the two groups were statistically significant(P<0.05).No significant differences were identified between the two groups in terms of advanced maternal age and gestational age(P>0.05).According to the results of the classification statistics,the most common intrac-ardiac abnormality was a ventricular septal defect and the most common extrac-ardiac abnormality was a single umbilical artery.In the subgroup analysis,the concurrent combination of intra-and extracardiac structural abnormalities was a risk factor for adverse pregnancy outcomes(odds ratio>1,P<0.05).Additional-ly,all abnormal cytogenetic findings on amniocentesis were observed in the comorbidity group.One case was diagnosed with 21-trisomy and six cases was diagnosed with chromosome segment duplication.CONCLUSION Examination for other structural abnormalities is strongly recommended when PLSVC is diagnosed.Poorer pregnancy outcomes and increased amniocentesis were observed in PLSVC cases with other structural abnor-malities.Amniotic fluid cytogenetics of fetuses is recommended for PLSVC with other structural abnormalities.

Endocrine and Cytogenetic Profile of Variations in Genital Development: Series of 9 Cases at the Mali Hospital

We carried out a retrospective and descriptive study in the Medicine and Endocrinology service of the Mali Hospital from January 2015 to December 2018. Nine cases of anomalies in sexual differentiation were referred for pubertal delay, growth retardation, gynecomastia, micropenis or infertility. Outcomes: The average age was 14 years;5 patients were declared female at birth;2 were married without children;7 patients came from the region of Kayes;8 patients consulted for pubertal delay;1 patient presented with association of a blind vagina and 2 bilateral inguinal gonads. 3 of 4 patients declared male at birth had a micropenis;2 patients had gynecomastia with a history of hypospadias. Ultrasound and biological data showed a clinical-hormonal picture of hypergonadotropic hypogonadism in 6 patients, 1 case of hypogonadotropic hypogonadism with hypercorticism and 2 cases with normal gonadotropic axis;two cases of azoospermia. Karyotypic analysis showed: 3 cases of SK, 2 cases of Klinefelter Syndrome, 2 cases of Androgen Insensitivity Syndrome and 2 cases of male 46 XX syndrome including one with sry negative. Conclusion: The precise diagnosis of anomalies in sexual differentiation remains complicated in Mali, due to the inadequacy of the technical platform. Diagnosis must be made at an early stage to allow normal growth, puberty and satisfactory fertility. Taking charge of the medical treatment possibly associated with plastic surgery could give good results.

Toward Molecular Cytogenetical Characterizations in Cotton Genome

Cotton is viewed as the most important cash crop in the world,and sustains the agricultural economies of many nations by providing a sustainable fiber product for the textile industry.Due to