MiR-744-5p inhibits the proliferation, invasion, and migration of clear-cell renal cell carcinoma cells by targeting CCND1 / 南方医科大学学报

OBJECTIVE@#To explore the role of miR-744-5p/CCND1 axis in clear-cell renal cell carcinoma (ccRCC).@*METHODS@#We examined the expression levels of miR-744-5p in 65 pairs of ccRCC and adjacent tissue specimens and in 5 ccRCC cell lines and human renal tubular epithelial (HK2) cells using qRT-PCR. The ccRCC cell lines 786-O and OSRC2 were transfected with miR-744-5p mimic, CCND1 mimic, or their negative control mimics, and the changes in cell proliferation, migration, and invasion were evaluated with CCK-8, wound healing, and Transwell assays. The downstream target molecules of miR-744-5p were predicted by bioinformatics analysis, and the expression level of CCND1 in ccRCC cells was verified by qRT-PCR and Western blotting. The relationship between miR-744-5p and CCND1 was further validated by dual luciferase reporter assay, and the role of the miR-744-5p/CCND1 axis in ccRCC was explored by rescue experiments.@*RESULTS@#MiR-744-5p was significantly downregulated in ccRCC tissues and cell lines (all P < 0.05), and its overexpression inhibited the proliferation, migration, and invasion of ccRCC cells (all P < 0.05). Bioinformatics analysis and dual luciferase reporter assay showed that CCND1 was a downstream target of miR-744-5p. The results of rescue experiments showed that upregulation of CCND1 could partially reverse the inhibitory effect of miR-744-5p overexpression on ccRCC cell proliferation, migration, and invasion (all P < 0.05).@*CONCLUSION@#MiR-744-5p inhibits the malignant phenotype of ccRCC cells by targeting CCND1, and the miR-744-5p/CCND1 axis may be a novel target for diagnosis and treatment of ccRCC.

miR-361-5p reverses oxaliplatin resistance of gastric cancer SGC-7901 cells by targeting CCND1 / 中国肿瘤生物治疗杂志

@#[Abstract] Objective: To investigate the effects of miR-361-5p on the oxaliplatin (OXA) resistance of gastric cancer SGC-7901 cells and its mechanism. Methods: The expression of miR-361-5p in gastric cancer cells (MKN-45, MGC80-3 and SGC-7901) and drug-resistant SGC-7901/OXA cells was detected by qPCR. The SGC-7901/OXA cells were transfected with miR-361-5p mimics/inhibitor or sh-CCND1 by using Liposome transfection technology. Then, cell proliferation, apoptosis and cell cycle of SGC-7901/OXA cells were measured by CCK-8 assay and Flow cytometry, respectively. The targeting relationship between miR-361-5p and CCND1 was examined by Dual luciferase report gene assay. The expression level of CCND1 in SGC-7901/OXA cells was detected by WB. Results: miR-361-5p was down-regulated in multiple gastric cancer cells and SGC-7901/OXA cells (P<0.05 or P<0.01). Over-expression of miR-361-5p significantly promoted the apoptosis, induced G0/G1 cell cycle arrest and inhibited cell proliferation of SGC-7901/OXA cells (P<0.05 or P<0.01). Dual luciferase reporter gene results verified that miR-361-5p targeted CCND1 and negatively regulated its expression (P<0.01). Further experiments showed that targeted down-regulation of CCND1 induced apoptosis and G0/G1 cell cycle arrest and inhibited CCND1 expression and proliferation of SGC-7901/OXA cells (P<0.05 or P<0.01). Over-expression of miR-361-5p targetedly down-regulated CCND1 and further promoted cell apoptosis, induced G0/G1 cell cycle arrest and inhibited cell proliferation of SGC-7901/OXA cells (P<0.05 or P<0.01). Conclusion: miR-361-5p over-expression can reverse the resistance of SGC-7901/OXA cells to OXA, and the mechanism may be related to its targeted down-regulation of CCND1 expression.

lncRNA HOTAIR promotes malignant biological behaviors of breast cancer SKBR3 cells through miR-519d-3p/CCND1 axis / 中国肿瘤生物治疗杂志

@#[Abstract] Objective: To explore the effect of lncRNA HOTAIR/miR-519d-3p/cyclin D1 (CCND1) axis on the proliferation and metastasis of breast cancer cells and its underlying mechanism. Methods: A total of 50 pairs of breast cancer tissues and corresponding para-cancer tissues resected from breast cancer patients in the Department of Breast Surgery, the Third Hospital of Nanchang from March 2017 to February 2019 were collected for this study. The expression level of HOTAIR in breast cancer tissues and paired paracancer tissues was detected by qPCR, in addition, the expressions of HOTAIR and miR-519d-3p in normal breast epithelial cells and breast cancer cell lines were also detected. Breast cancer SKBR3 cells were divided into NC group (without any treatment), si-HOTAIR group, mir-519d-3p mimics group, miR-519d-3p mimic+pcHOTAIR group, miR-519d-3p mimic+pcCCND1 group, and si-HOTAIR+ pcCCND1 group. The proliferation ability of SKBR3 cells was detected by CCK-8. Invasion and migration of SKBR3 cells were detected by Transwell. The expression levels of E-cadherin, N-cadherin, Vimentin and CCND1 in SKBR3 cells were detected by Western blotting. The targeting relationship between HOTAIR and miR-519d-3p, miR-519d-3p and CCND1 was detected by Dualluciferase reporter gene system. Results: HOTAIR was highly expressed in breast cancer tissues and cell lines, with the highest expression in SKBR3 cells. HOTAIR knockdown significantly inhibited the proliferation, invasion and migration of SKBR3 cells, as well as increased the expression level of E-cadherin and decreased the expression levels of N-cadherin and Vimentin. Dual-luciferase reporter gene assay showed that HOTAIR targetedly down-regulated the expression of miR-519d-3p, and miR-519d-3p targetedly downregulated the expression of CCND1. Further studies showed that knockout of HOTAIR inhibited the EMT, proliferation, invasion and migration of SKBR3 cells through enhancing the inhibitory effect of miR-519d-3p on CCND1 expression (all P<0.05). Conclusion: HOTAIR knockdown inhibits proliferation and metastasis of SKBR3 cells by regulating the axis of miR-519d-3p/CCND1.

circ_0005075 promotes proliferation and invasion of liver cancer HCCC9810 cells by sponging miR-335 / 中国肿瘤生物治疗杂志

@#Objective: To explore the effect of circ_0005075 on the proliferation and invasion of liver cancer cells and its underlying mechanism. Methods:Atotal of 35 cases of cancer tissues and corresponding para-cancerous tissues from liver cancer patients, who underwent surgical resection in Tangshan Workers’Hospital from March 2015 to March 2018, were collected for this study. qPCR was used to detect the expression levels of circ_0005075 and miR-335 in liver cancer tissues, para-cancerous tissues, liver cancer cell lines (HCCC9810, HepG2, HLE and hepatic epithelial THLE-3 cells). Dual luciferase reporter gene assay was used to verify the targeting relationship among circ 0005075, mir-335 and CCND1. By using liposome-mediated method, Sh-circ_0005075, miR-335 mimics, miR335 mimics+pcDNA-CCND1, sh-circ_0005075+pcDNA-CCND1, pcDNA-circ_0005075+miR-335 mimics, sh-CCND1+pcDNA-circ_ 0005075 were transfected into HCCC9810 cells, respectively. The effects of circ_0005075/miR-335/CCND1 molecular axis on the proliferation and invasion of HCCC9810 cells were detected by MTT and Transwell methods. Results: circ_0005075 was highly expressed in liver cancer tissues and cell lines (P<0.01) ,and the highest expression in HCCC9810 cells (P<0.05). Dual luciferase reporter gene results showed that circ_0005075 negatively regulated miR-335 (P<0.05), and CCND1 was a target gene of miR-335 (P<0.05). Further experiments proved that knockdown of circ_0005075 or overexpression of miR-335 could inhibit the proliferation and invasion of HCCC9810 cells by regulating CCND1（P<0.05 or P<0.01） . Conclusion: Circ_0005075 upregulates the expression level of CCND1 by sponging miR-335, thereby promoting the proliferation and invasion of HCCC9810 cells.

BjussuLAAO-II induces cytotoxicity and alters DNA methylation of cell-cycle genes in monocultured/co-cultured HepG2 cells

The use of animal venoms and their toxins as material sources for biotechnological applications has received much attention from the pharmaceutical industry. L-amino acid oxidases from snake venoms (SV-LAAOs) have demonstrated innumerous biological effects and pharmacological potential against different cancer types. Hepatocellular carcinoma has increased worldwide, and the aberrant DNA methylation of liver cells is a common mechanism to promote hepatic tumorigenesis. Moreover, tumor microenvironment plays a major role in neoplastic transformation. To elucidate the molecular mechanisms responsible for the cytotoxic effects of SV-LAAO in human cancer cells, this study aimed to evaluate the cytotoxicity and the alterations in DNA methylation profiler in the promoter regions of cell-cycle genes induced by BjussuLAAO-II, an LAAO from Bothrops jaracussu venom, in human hepatocellular carcinoma (HepG2) cells in monoculture and co-culture with endothelial (HUVEC) cells. Methods: BjussuLAAO-II concentrations were 0.25, 0.50, 1.00 and 5.00 μg/mL. Cell viability was assessed by MTT assay and DNA methylation of the promoter regions of 22 cell-cycle genes by EpiTect Methyl II PCR array. Results: BjussuLAAO-II decreased the cell viability of HepG2 cells in monoculture at all concentrations tested. In co-culture, 1.00 and 5.00 μg/mL induced cytotoxicity (p < 0.05). BjussuLAAO-II increased the methylation of CCND1 and decreased the methylation of CDKN1A in monoculture and GADD45A in both cell-culture models (p < 0.05). Conclusion: Data showed BjussuLAAO-II induced cytotoxicity and altered DNA methylation of the promoter regions of cell-cycle genes in HepG2 cells in monoculture and co-culture models. We suggested the analysis of DNA methylation profile of GADD45A as a potential biomarker of the cell cycle effects of BjussuLAAO-II in cancer cells. The tumor microenvironment should be considered to comprise part of biotechnological strategies during the development of snake-toxin-based novel drugs.(AU)

Increased levels of cyclin D1 negatively impacts on acute lymphoblastic leukemia overall survival

Background: Cyclin D1 is a protein essential for transition from G1 to S phase during cell cycle progression, which has an oncogenic potential and is highly expressed in several human malignancies. However, in view of the heterogeneity of the findings in the literature, the prognostic value of cyclin D1 expression still needs to be validated in different cohorts of adult acute lymphoblastic leukemia (ALL) patients. Methods: Bone marrow samples from 13 healthy donors and 45 adult patients with acute lymphoblastic leukemia were included. Cyclin D1 gene expression was evaluated by quantitative PCR. For statistical analysis, Mann­Whitney test, Fisher's exact test, Chi-squared test and Cox regression were used, as appropriate. All p values were two-sided with a significance level of 5%. Results: Cyclin D1 mRNA levels were similar between primary cells from ALL patients and healthy donors. In ALL patients, high cyclin D1 expression was associated with older age at the diagnosis, presence of BCR-ABL1, and lower white blood cell counts. Importantly, increased cyclin D1 expression was an independent factor that predicted worse overall survival in our adult ALL cohort. Conclusion: Increased levels of cyclin D1 negatively impacted on ALL survival outcome, suggesting that this gene is involved in the malignant phenotype of ALL.

Genética molecular del melanoma lentiginoso acral / Molecular genetics of acral lentiginous melanoma

En la última década se ha avanzado en la caracterización genética y mapeo molecular del melanoma cutáneo con el objetivo de identificar y comprender mejor los mecanismos patogénicos propios de cada subgrupo y así desarrollar tratamientos específicos. El melanoma lentiginoso acral (MLA) constituye un subtipo de melanoma con características clínicas, epidemiológicas, histopatológicas, pronósticas y terapéuticas distintivas y su perfil mutacional no es la excepción. A diferencia del melanoma ubicado en zonas fotoexpuestas, el MLA presenta una baja tasa de mutaciones BRAF (15%) y mayor frecuencia de amplificaciones y ganancias genéticas de KIT (15-30%), CCND1 (15-40%) y TERT (20%). En esta revisión se describen las características más relevantes del MLA con énfasis en el rol que cumplen los principales genes que participan en la patogenia del MLA.

Over the last decade, the genetic characterization and molecular mapping of cutaneous melanoma has been developed in order to identify and better understand the pathogenic mechanisms of each subgroup and to develop specific treatments. Acral lentiginous melanoma (ALM) is a melanoma subtype with distinctive clinical, epidemiological, histopathological, prognostic and therapeutic features and its mutational profile is not an exception. Unlike melanoma located in photoexposed areas, MLA has a low rate of BRAF mutations (15%) and a higher frequency of amplifications and genetic gains at KIT (15-30%), CCND1 (15-40%) and TERT (20%). In this review we will describe the most relevant characteristics of MLA with emphasis on the role of the main genes involved in its pathogenesis.

Expression of IgH/CCND1 fusion gene and cell cycle associated protein in mantle cell lymphoma / 临床与实验病理学杂志

Purpose To investigate the expression of cell cycle related protein including Cyclin D1,CDK4,p16 and IgH/CCND1 fusion gene in mantle cell lymphoma (MCL) and their relationship with each other.Methods The expression of cell cycle related protein including Cyclin D1,CDK4,p16 and IgH/CCND1 fusion gene were detected on the 40 cases of MCL (expreimental group) and 20 cases of reactive hyperplasia (control group) by using the combined detection of fluorescence in situ hybridization (FISH) and immunohistochemistry of EnVision two methods.40 cases of MCL were confirmend by using gene rearrangement technique and immunohistochemistry.The threshold of IgH/CCND1 fusion gene of MCL was established in the control group.Results In the experimental group,Cyclin D1 protein positive expression rate was 100％,the positive expression of CDK4 protein rate was 87.50％,p16 protein positive expression rate was 17.50％.Positive rate of IgH/CCND1 fusion gene of 100％.These cell cycle related protein and IgH/CCND1 fusion gene were negative in the control group.Conclusion In MCL,Cyclin D1-CDK4-p16 pathway is consistent with the principle of tumor cell cycle regulation.The establishment of threshold value of IgH/CCND1 fusion gene by FISH technique may provide the basis for the judgement of FISH of the IgH/CCND1 in China.

Mechanism of Inhibition of Neuroblastoma Cell Proliferation by Elemene / 中国医科大学学报

Objective To investigate the effect of elemene and the mechanism of this effect on the proliferation of neuroblastoma.Methods We treated cultured SK-N-SH cells with elemene and used the MTT assay to determine the inhibition of cell proliferation.We used RT-qPCR and Western blotting to measure the effect of elemene on mRNA and protein expression,respectively,of repressor element-1 silencing transcription factor (REST) in SK-N-SH cells and evaluated the mRNA expression of CCND1 and CCNE1 in SK-N-SH cells by using RT-qPCR.Results Elemene significantly inhibited the proliferation of SK-N-SH cells in a dose-and time-dependent manner (P =0.001 16).Moreover,the mRNA (P =0.000 38) and protein (P =0.003 39) expression of REST were markedly suppressed by elemene.Furthermore,elemene significantly reduced the mRNA expression of CCND1 (P =0.001 91) and CCNE1 (P =0.000 15),which are related to the cell cycle.Conclusion Elemene significantly suppressed the proliferation of neuroblastoma cells through the reduction of REST,CCND1,and CCNE1.

Effect and mechanism of transcription factor Foxp3 on proliferation and cell cycle of human lung adenocarcinoma cell A549 / 中国免疫学杂志

Objective:To investigate the effect and mechanism of transcription factor Foxp 3 on the proliferation and cell cycle of human lung adenocarcinoma cell line A 549.Methods:We knocked down the expression of Foxp 3 using siRNA.Foxp3 inhibition was detected by RT-PCR.Cell proliferation was detected by MTT.Cell cycle of A549 cells were detected by flow cytometry after the transfection of siRNA.Cell cycle-related checkpoint genes were filtered by RT-PCR.The regulation of Foxp3 on cell cycle-related checkpoint genes were detected by immunofluorescence and dual -luciferase reporter assay system.Results: The proliferation of A549 cells were inhibited after silencing Foxp3,and A549 cells were arrested in G0/G1 cycle.G1/S cycle checkpoint gene CCND1 was down regulated.Mechanism research show that Foxp 3 can regulate the expression of CCND 1 directly.Conclusion: Foxp3 can promote the proliferation of A549 cell line by up regulating G 1/S cycle checkpoint gene CCND 1.This provides a new target for the therapeutic targets of lung adenocarcinoma.

Down regulation of miR-203 in radiation-induced thymic lymphoma promoted cells proliferation and inhibited apoptosis / 中华放射医学与防护杂志

Objective To investigate the role of miR-203 in radiation-induced thymic lymphoma (RITL).Methods A 60Co irradiator was used for total-body irradiation.MicroRNAs(miRNAs) level was assayed by qRT-PCR.Cell proliferation was assayed by MTT assay.Cell apoptosis was examined by fluorescence activated cell sorter (FACS).Dual luciferase reporter assay system was used to detect the 3'UTR reporter.Results MiR-203 was down-regulated in RITL tissues.Overexpression of miR-203 strongly inhibited the proliferation of both NIH3T3 cells and EL4 cells and vice versa.MiR-203 inhibited cells proliferation and induced apoptosis via TANK-binding kinase (TBK1),SLUG (SNAI2) and Cyclin D1 (CCND1).Conclusions Radiation down-regulated the level of miR-203 in thymic,which promoted radiation-induced thymic lymphoma by targeting TBK1,SNAI2 and CCND1.

CD5-negative Blastoid Variant Mantle Cell Lymphoma with Complex CCND1/IGH and MYC Aberrations

The coexistence of CCND1/IGH and MYC rearrangements in mantle cell lymphoma (MCL) is a rare finding associated with a very poor prognosis. In this study, a patient with blastoid variant (MCL) is reported. The disease was clinically aggressive and refractory to chemotherapy, and the patient only survived for 1 month following diagnosis. Conventional cytogenetic study, FISH, and multicolor FISH (mFISH) demonstrated the involvement of the BCL1/CCND1 locus in a complex translocation, t(3;11)(q25;p15)t(11;14)(q13;q32). In addition, subclonal abnormalities in the 8q24 region, manifested as a t(8;14)(q24;q32)/MYC rearrangement, were identified. To the best of our knowledge, this is the first MCL case in Korea bearing these complex genomic aberrations.

Influence of murine cytomegalovirus infection on the differentiation and the differentiation genes expression in neural stem cells / 中国病理生理杂志

AIM: The influence of MCMV infection on differentiation and differentiation gene expression in neural stem cells ( NSCs) in vitro were investigated for studying the mechanisms of brain abnormalities caused by congenital cytomegalovirus infection. METHODS: NSCs were separated from fetal BALB/C mouse, and cultured and identified in vitro. The differentiation potency of NSCs was observed by immunofluorescence. The NSCs infected by MCMV at dosage of MOI( multiplicity of infection) equaled to 5, 1 and 0.1 .respectively, were cultured in differentiation medium. The morphological changes of infected cells were observed under inverted microscope. The ratios of NSCs and its differentiated cells were detected by flow cytometry. The expressions of nestin, GFAP and NSE, markers of NSCs and its differentiated cells, were studied by immunofluorescence( MOI = 1). The expression of early antigen ( EA ) of MCMV was detected to observe the infection process. Real - time RT - PCR method was employed to measure the expression levels of the key genes Neurog2, Myc and Ccnd1 in Wnt signal pathway of NSCs at early stage of differentiation culture. RESULTS: NSCs isolated from embryonic mouse brains proliferated to form neurospheres, strongly expressed nestin and differentiated into NF - 200 positive neurons or GFAP positive astrocytes. The infected NSCs did not adhere to the wall and appeared differentiation growths, but showed swollen gradually after differentiation culture. The nestin expression in the infected cells downregulated slowly and was higher than that in control groups ( P < 0.05). The GFAP and NSE expressions of the infected cells were lower than those in control groups ( P <0.05). The early antigen ( EA) of MCMV was always detected in the cells in infected groups. The ratios of nestin positive cells in infected groups were higher than those in control groups, but the ratios of GFAP and NSE positive cells of former were lower than that of the latter from 3rd to 9th d after differentiation culture(P < 0.05 ). The levels of Neurog2 mRNA and Myc mRNA in infected groups were markedly lower than those in normal control groups on 1st d and from 1st to 4th d after differentiation culture, respectively( P <0.05). The levels of Ccnd1 mRNA of infected groups were obviously lower than those in normal control groups from 12th h to 1st d( P <0.05 ). These changes in infected groups became more obvious as MCMV MOI increased. CONCLUSION: MCMV significantly inhibits differentiation of NSCs to neurons and astrocytes, and leads to the decrease in differentiated cells. MCMV inhibits or interferes with the gene expression of Newog2, Myc and Ccnd1 in Wnt signal pathway of NSCs. The effect that MCMV inhibits the expressions of differentiation and the differentiation genes in NSCs shows dose - dependent with MCMV MOI. The inhibitory effect of MCMV on the differentiation of NSCs might be induced by interfering with the expression of differentiation gene in NSCs, which is possibly the one of primary causes of brain development disorders induced by congenital CMV infection.

Peripheral position of CCND1 and HER-2/neu oncogenes within chromosome territories in esophageal and gastric cancers non-related to amplification and overexpression

Interphase chromosomes have been shown to occupy discrete regions of the nucleus denominated chromosome territories (CTs), their active genes being preferentially positioned on the surfaces of these CTs, where they are accessible to transcriptional machinery. By means of FISH (Fluorescence in situ Hybridization), we analyzed the CCND1 and HER-2/neu gene positions within the CTs and their relationship with gene amplification and protein over-expression in esophageal and gastric cancers. The CCND1 and HER-2/Neu genes were more often positioned at the periphery (mean frequency of 60 percent-83 percent) of the CTs in tumor tissues of the esophagus and stomach. Moreover, this positioning revealed no association with either gene amplification or the protein over-expression status of these genes, although, in esophageal carcinoma, Kappa statistics showed a moderate agreement between amplification of the CCND1 gene (Kappa = 0.400) and its location within the CT, as well as with over-expression of the corresponding protein (Kappa = 0.444). Thus, our results suggest that gene positioning in interphase chromosomes does not follow a definitive pattern neither does it depend only on gene transcriptional activity. Apparently, this positioning could be both gene- and tissue-specific, and depends on other factors acting together, such as dense-gene, chromosome size, chromatin structure, and the level and stability of its expression.

CCND1 gene A870G polymorphism and genetic susceptibility to prostate cancer / 中华泌尿外科杂志

Objective To investigate the possible association between the CCND1 A870G polymorphism and susceptibility to prostate cancer(PCa)in a Chinese population.Methods The CCND1 A870G genotypes were determined by TaqMan assays in 245 PCa cases and age-matched 245 controis.Odds ratios(OR)for PCa and 95%confidence intervals(CI)from unconditional logistic regression models were used to evaluate relative risks.Age,a potential PCa risk factor,was included in the logistic regression models as a covariate in the multivariate analyses on genotype and PCa risk.Results The frequencies for G and A alleles were 0.476,0.524 in PCa cases,and 0.408 and 0.592 in controls,respectively.The G allele was marginally significantly associated with the presence of PCa (P=0.054)and had an increased risk for PCa(OR=1.31,95%CI=1.00-1.72)as compared to theA allele.Compared to AA homozygote,AG heterozygote had a 1.43-fold increased risk(95%CI=0.89-2.31,P=0.142),whereas GG homozygote had a significantly higher 2.02-fold increased risk (95%CI=1.07-3.80,P=0.029)of PCa(Armitage's trend test,P=0.029).The G allele(AG or GG genotype)was more frequently found in PCa patients with metastasis than those without metastasis(P=0.014).Conclusion The G allele of CCND1 A870G is associated with the presence of PCa and GG homozygote is potentially one of the genetic risk factors for PCa in Chinese population.The G allele may be associated with the progression of PCa metastasis.

Mantle Cell Lymphoma/Leukemia in Bone Marrow: Lacking Evidence of t(11;14) / 대한임상병리학회지

BACKGROUND: Mantle cell lymphoma/leukemia (MCL) is a distinctive disease entity that has been characterized by specific histopathologic, immunologic, and cytogenetic features. The characteristic cytogenetic abnormality of MCL is t(11;14)(q13;q32), that results in cyclin D1 overexpression. We have experienced 12 MCL cases with bone marrow involvement that were lacking evidence of t(11;14). We tried to review the cases. METHODS: We reviewed the bone marrow findings, immunophenotypic, cytogenetic studies including fluorescent in situ hybridization (FISH) analysis using IGH/CCND1 probes and medical records of 12 patients that were diagnosed with MCL based on immunophenotypic results during the period 1997 to 2001. RESULTS: The patients had a median age of 63 (50-70) years with male-to-female ratio of 3:1. All patients showed hepatosplenomegaly with varying degrees of peripheral blood involvement (2-93%), and lymphocytosis was found in 7 cases. Other presenting features were palpable lymph nodes (83%) and B symptoms (25%). The malignant cells were quite heterogenous in morphology from centrocytic to blastic variants. Most cases showed typical immunophenotypes-expression of CD19, bright CD20, FMC7, CD5 and bright-light chains with negative CD23. Immunohistochemical staining with cyclin D1 on marrow biopsies showed mostly negative results. Among the eleven cases in which cytogenetic studies were possible, four cases showed complex karyotypes, and three that involved 14q32. Strikingly, no one showed t(11;14) in G-banding analysis and only 2 cases showed IGH/CCND1 rearrangement by FISH. CONCLUSTIONS: Most MCL cases with typical immunophenotypic findings did not show evidence of specific cytogenetic features. Although further workups for molecular pathogenesis and clinical follow-up of the above cases need to be done, we suggest a new disease entity, t(11;14)-negative MCL.