ABSTRACT
Objective:To explore the risk stratification and prognostic significance of loss of chromosome Y (LOY) in patients with multiple myeloma (MM).Methods:The clinical data of 193 male patients with newly diagnosed MM admitted to Zhongshan Hospital of Fudan University from January 2018 to January 2020 were analyzed retrospectively and divided into a normal karyotype group(178) and a LOY karyotype group (15) according to the results of their primary conventional cytogenetics. Rank sum test, 2×2 chi-square test and independent sample t-test were used to compare laboratory findings, such as liver and kidney function, immunohistochemistry and cytogenetics, treatment efficacy and survival prognosis, between the two groups. The clinical prognostic significance of LOY was summarized through survival analysis and Cox regression. Results:Among the newly diagnosed male MM patients, 8%(15/178) were confirmed with LOY cases. The proportion of patients with Revised International Staging System(R-ISS) stage Ⅲ was significantly higher in the LOY group (8/15) than that in the normal karyotype group (40/178)(χ 2=7.052, P<0.01). A higher proportion of 1q21 amplification also occurred in the LOY group (10/13 vs 77/162)(χ 2=4.159, P<0.05). The proportion of complete response(CR)/stringent complete response(sCR) in the normal karyotype group after the fourth chemotherapy (63/171) was significantly higher than that in the LOY group (1/15)(χ 2=5.564, P<0.05). The proportion of progressive disease (PD) was lower in the normal karyotype group (16/171 vs 4/15) (χ 2=4.306, P<0.05). The 2-year progression-free survival (PFS) of MM patients for the LOY group was significantly shorter compared to that for the normal karyotype group ( Z=?3.201, P<0.01). Univariate survival analysis showed that PFS was significantly shorter in newly diagnosed MM patients with Creatinine(Cr)≥93 μmol/L, β 2-microglobulin (β 2-MG)≥4.0 mg/L, serum free light chain(sFLC)<0.06, bone marrow plasma cells (BMPC)≥30%, R-ISS stage Ⅲ, failure to achieve CR/sCR after the fourth chemotherapy, with LOY, 1q21 amplification, P53 deletion and t(4;14) ( P<0.05). Cox regression analysis showed that Cr≥93 μmol/L( HR=4.460, 95% CI 1.615-12.314, P=0.004), sFLC<0.06( HR=2.873, 95% CI 1.206-6.849, P=0.017), failure to achieve CR/sCR after the fourth chemotherapy( HR=3.522, 95% CI 1.437-8.634, P=0.006)and with LOY( HR=3.485, 95% CI 1.473-8.249, P=0.006)were independent risk factors for PFS in newly diagnosed MM patients. Conclusions:LOY is an independent risk factor for poor prognosis. It is important for the clinical outcome and prognosis of patients with newly diagnosed MM, and may become a novel clinical assessment indicator.
ABSTRACT
Loss of chromosome Y (LOY) in the bone marrow has long been considered as an age-related phenomenon with an incidence of more than 25% in males beyond the age of 80 years. Though reported as an acquired abnormality in myeloid neoplasms, it has rarely been described in B-lymphoblastic leukemia which primarily is a disease of the young. We describe here in three cases of pediatric B-lymphoblastic leukemia with LOY. Conventional cytogenetic studies and fluorescence in situ hybridization studies using centromeric probes for chromosome X and Y on peripheral blood samples ruled out constitutional LOY in all the three cases favoring it to be a neoplastic phenomenon.
ABSTRACT
The present-day Brazilian population is a consequence of the admixture of various peoples of very different origins, namely, Amerindians, Europeans and Africans. The proportion of each genetic contribution is known to be very heterogeneous throughout the country. The aim of the present study was to compare the male lineages present in two distinct Brazilian populations, as well as to evaluate the African contribution to their male genetic substrate. Thus, two Brazilian population samples from Manaus (State of Amazon) and Ribeirão Preto (State of São Paulo) and three African samples from Guinea Bissau, Angola and Mozambique were typed for a set of nine Y chromosome specific STRs. The data were compared with those from African, Amerindian and European populations. By using Y-STR haplotype information, low genetic distances were found between the Manaus and Ribeirão Preto populations, as well as between these and others from Iberia. Likewise, no significant distances were observed between any of the African samples from Angola, Mozambique and Guinea Bissau. Highly significant Rst values were found between both Brazilian samples and all the African and Amerindian populations. The absence of a significant Sub-Saharan African male component resulting from the slave trade, and the low frequency in Amerindian ancestry Y-lineages in the Manaus and Ribeirão Preto population samples are in accordance with the accentuated gender asymmetry in admixture processes that has been systematically reported in colonial South American populations.
Subject(s)
Humans , Male , Chromosomes, Human, Y/genetics , Ethnicity/genetics , Microsatellite Repeats , Black People , Genetic Markers , Genetic Variation , Genetics, Population , Indians, South AmericanABSTRACT
PURPOSE: There have only been a few cytogenetic studies of hepatocellular carcinoma (HCC), and so far, no consistent specific chromosomal abnormalities have been described. Here, we have used comparative genomic hybridization (CGH), a powerful molecular cytogenetic technique for detecting changes of the copy number throughout the genome, to screen for genetic alterations in HCC cell lines. The CGH results were compared with those derived from G-banding and chromosome painting. MATERIALS AND METGODS: Conventional cytogenetic analyses were performed on five HCC cell lines, SNU-354, SNU-368, SNU-387, SNU-449 and SNU-475, using a G- banding staining technique. In CGH, equal amounts of differently labeled DNA from the cell lines, and normal reference DNA, were hybridized simultaneously to normal metaphase chromosomes. They were visualized by different fluorochromes, and the signal intensities quantified separately as gray levels along the single chromosomes. The over- and under-represented DNA segments were determined by computation of ratio images and average ratio profiles. To confirm the CGH results, florescence in situ hybridization (FISH), with chromosome specific painting, was performed using indirectly labeled chromosome specific paints. RESULTS: Complex unbalanced chromosomal aberrations, which could not be identified reliably by conventional cytogenetics in HCC cell lines, were successfully resolved by CGH analysis. CGH results were validated using FISH with chromosome specific probes. In HCC cell lines, gains in DNA copy number were more common than losses. The most prominent changes were gains of 1q12- qter (80% of cases), 1q41-qter (100%), 7 (80%), 8q12-qter (60%), 8q23-qter (80%) and 20q12-qter (60%). Recurrent losses were mapped on 4q13-qter (60%), 16q12-qter (60%), 16q21-qter (80%), 13q12-q14.2 (60%) and Yq11.2 (100%). All four male HCC cell lines showed loss or rearrangement of the Y chromosome. CONCLUSION: Conventional cytogenetics, CGH and FISH using painting probes, represent complementary approaches that, when employed in combination, could greatly facilitate the comprehensive analysis of chromosomal imbalances in HCC cell lines. Our results suggest the existence of an oncogene, or protooncogenes, on chromosome 1q41-qter, and the tumor suppressor genes on Yq11.2, that play a role in the development and/or progression of hepatocellular carcinogenesis.