[Amplifiation of the c-MYC gene in acinar prostate adenocarcinoma. Morphogenic comparisons]. / Amplifikatsiya gena c-MYC pri atsinarnoi adenokartsinome prostaty. Morfogeneticheskie sopostavleniya.

OBJECTIVE: The purpose of this work was to evaluate c-MYC gene amplification in the substrate of prostate acinar adenocarcinoma at various Gleason scores and various stages of the disease, taking into account the morphological characteristics of the tumor. MATERIAL AND METHODS: The number of cases in the study was 82, including the control group - 12 cases. Morphological assessment included: determination of the total Gleason score, grading group, assessment of lymphovascular/perineural invasion, and architectural characteristics of the tumor. Gene amplification was assessed by FISH using the c-MYC (8q24)/SE8 probe. RESULTS: In all cases of the study group, amplification of the c-MYC gene was detected in the tumor, with a significant difference from the control group (p<0.05). When assessing cases with 4-6 fold copies of the gene, significant differences were established between patients with stages II and III of the disease and stage IV (10.0 and 13.5 versus 30.0) (p<0.05). Cluster amplification of the c-MYC gene was detected with equal frequency in groups of patients with stages III and IV of the disease, while in stage II of the disease, the event almost did not occur (p<0.05). A significant increase in the level of c-MYC gene amplification was found in groups with advanced stages of the disease (p<0.02). Non-cluster amplification significantly distinguishes T4M0 and T4M1 stage patients from the rest with a significant increase in the score (p<0.05). In the metastatic stage of the disease, there was an increase c-MYC gene amplification compared to the non-metastatic stage (p<0.02). The copy number of the c-MYC gene was significantly higher in cases with perineural and lymphovascular invasion, as well as in cases of cribriform tumor organization (p<0.05). CONCLUSION: Amplification of the c-MYC gene in prostate tumor cells is associated with advanced stages of the disease (T4M0 and T4M1) with an increase in the copy number of the gene during the metastatic stage of the process. It was found that increased amplification of the c-MYC gene distinguishes groups of patients whose tumors exhibit perineural and lymphovascular invasion, as well as a cribriform pattern of tumor organization.

Impact of coconut kernel extract on carcinogen-induced skin cancer model: Oxidative stress, C-MYC proto-oncogene and tumor formation.

This study aimed at analysing the effects of coconut (Cocos nucifera L.) kernel extract (CKE) on oxidative stress, C-MYC proto-oncogene, and tumour formation in a skin cancer model. Tumorigenesis was induced by dimethylbenz[a]anthracene (DMBA)/12-O-tetradecanoylphorbol-13-acetate (TPA). In vitro antioxidant activity of CKE was assessed using 2, 2-diphenyl-1-picrylhydrazyl (DPPH), hydrogen peroxide (H2O2), total phenolic and flavonoid content assays. CKE showed a higher antioxidant activity then ascorbic acid (*P < 0.05, ****P < 0.0001). HPLC and NMR study of the CKE revealed the presence of lauric acid (LA). Following the characterization of CKE, mice were randomly assigned to receive DMBA/TPA Induction and CKE treatment at different doses (50, 100, and 200 mg/kg) of body weight. LA 100 mg/kg of body weight used as standard. Significantly, the CKE200 and control groups' mice did not develop tumors; however, the CKE100 and CKE50 treated groups did develop tumors less frequently than the DMBA/TPA-treated mice. Histopathological analysis revealed that the epidermal layer in DMBA-induced mice was thicker and had squamous pearls along with a hyperplasia/dysplasia lesion, indicating skin squamous cell carcinoma (SCC), whereas the epidermal layers in CKE200-treated and control mice were normal. Additionally, the CKE treatment demonstrated a significant stimulatory effect on the activities of reactive oxygen species (ROS), glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD), as well as an inhibitory effect on lipid peroxidase (*P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001) and c-MYC protein expression (*P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001). In conclusion, CKE prevents the growth of tumors on mouse skin by reducing oxidative stress and suppressing c-MYC overexpression brought on by DMBA/TPA induction. This makes it an effective dietary antioxidant with anti-tumor properties.

Burkitt Lymphoma Presenting as Obstructive Jaundice: A Case Report and Literature Review.

Burkitt lymphoma (BL) is an aggressive, high-grade B-cell lymphoma common in children and young adults. Despite being frequently discovered in extranodal sites, BL rarely occurs in the pancreas. We present a case of a patient with BL presenting as obstructive jaundice.

[Prompt cytogenetic response by venetoclax plus azacitidine regimen in a patient with AML harboring double-minute chromosomes with MYC gene amplification].

Double minute chromosomes (dmin) are small, acentric, and extrachromosomal fragments that frequently mediate oncogene amplification and induce rapid disease progression with poor prognosis, although they are infrequent in myeloid neoplasms. An 81-year-old woman with anemia and thrombocytopenia was admitted to our hospital. Bone marrow examination showed 54.0% of the blasts. She was diagnosed with acute myeloid leukemia (French-American-British classification, M2; World Health Organization classification, acute myeloid leukemia [AML], not otherwise specified, AML with maturation). Chromosomal analysis revealed the presence of 3-45 dmin in the background of 46 and XX in 14 out of 20 metaphases examined. Spectral karyotyping examination demonstrated that the dmins were derived from chromosome 8. Fluorescence in situ hybridization (FISH) targeting the MYC gene demonstrated that dmins contained full-length MYC genes with multiple signals. Finally, she was diagnosed with AML with dmin via MYC amplification and was administered with venetoclax plus azacitidine chemotherapy. After two cycles of the regimen, FISH found no MYC amplification signals, indicating her state being in cytogenetic remission. At present, she has finished four cycles of the regimen and remained in complete remission. Venetoclax plus azacitidine could be an effective regimen for the poor prognosis of AML with dmin through MYC amplification.

HIV-associated DLBCL: Clinicopathological factors including dual-colour chromogenic in situ hybridisation to assess MYC gene copies.

INTRODUCTION: Diffuse large B-cell lymphoma (DLBCL) comprises up to 43% of non-Hodgkin lymphomas in South Africa due to the high seroprevalence of human immunodeficiency virus (HIV) infection in the southern African region. We explored the prognostic influence of an array of clinicopathological factors, including MYC gene copy numbers, within HIV-associated DLBCL. METHODS: The retrospective inclusion of 123 tumours was followed by c-MYC immunohistochemistry and dual-colour MYC and centromere 8 (CEN8) chromogenic in situ hybridisation on formalin-fixed paraffin-embedded sections. Clinicopathological data were collected, interpreted and analysed. RESULTS: HIV seropositive patients comprised 81% (93/115), mean age 42 (SD 10.8) years, with 55% males, HIV negative patients comprised 19% (22/115), mean age 57 (SD 16.7) years (p = 0.001), with 59% males and the HIV status was unknown for 8 patients. The median CD4 count was 162 (IQR 215) cells/mm3, 33% of patients presented with CD4 counts <100 cells/mm3 and the median viral load was 217 (IQR 182 981) copies/mL. There was advanced stage at presentation (i.e., III-IV, 87%), with Ki-67 proliferation indices ≥90% in 85%- and c-MYC expression (i.e., ≥40%) in 58% of tumours. Double expression of c-MYC and BCL2 was associated with a non-germinal center immunophenotype (p < 0.01). Low-level increase of MYC gene copy numbers and MYC rearrangements occurred in 57% and 12%, respectively. C8 polysomy, MYC gene clusters and concurrent MYC rearrangement/increased MYC gene copies were also detected. Inferior median overall survival (OS) occurred when the CD4 counts were <100 cells/mm3 (149 days 95% CI 44-254, p 0,04) and when IPI scores were 3-5 [155 days (95% CI 37-273), p = 0.01]. Concomitant infections negatively impacted the survival outcome, multivariate regression analysis (HR 4.01, 95% CI 1.86-12.20, p = 0.02). CONCLUSION: c-MYC protein expression, low-level increase in MYC gene copy numbers, rearrangement, C8 polysomy, MYC gene clusters and concurrent MYC rearrangement/low-level gains are present in HIV+ DLBCL. CD4 counts < 100 cells/mm3, IPI scores 3-5 and concomitant infections negatively impact the survival outcome.

The Prognostic Impact of MYC Gene-Related Abnormalities on Multiple Myeloma Outcome through Fluorescence in situ Hybridization Analysis.

INTRODUCTION: Chromosomal abnormalities (CAs) have been identified as important factors in determining the biological features and prognostic value of multiple myeloma (MM). MYC gene-related abnormalities (MYC GAs) are one of the CAs, but their unfavorable impact has not been fully investigated in daily clinical practice. METHODS: This study retrospectively analyzed the prognostic impact of MYC GAs on 81 patients through fluorescence in situ hybridization analysis in our institute. RESULTS: MYC GAs were associated with poor overall survival (hazard ratio [HR], 3.08; 95% confidence interval [CI]: 1.23-7.73; p = 0.017), progression-free survival (PFS) (HR, 2.96; 95% CI: 1.58-5.53; p < 0.001), and time to next treatment (TNT) (HR, 2.11; 95% CI: 1.13-3.93; p = 0.018) in the median follow-up of 34.7 months. Furthermore, MYC GAs with an additional chromosome 8 (MYC-Ch8(+)) were associated with shorter PFS (HR, 3.15; 95% CI: 1.38-7.2; p = 0.0064), whereas MYC GAs without an additional chromosome 8 (MYC-Ch8(-)) were associated with shorter PFS (HR, 3.62; 95% CI: 1.51-8.68; p = 0.004) and shorter TNT (HR, 3.72; 95% CI: 1.41-9.81; p = 0.0078). CONCLUSION: These findings could help identify high-risk patients with MM. Further prospective studies are needed to confirm the significance of MYC GAs for the MM prognostic effect.

Plasmablastic lymphomas show restricted EBV latency profile and MYC gene aberrations.

The pathogenesis of plasmablastic lymphoma (PBL) involves the Epstein-Barr virus (EBV), human immunodeficiency virus (HIV), and MYC gene aberrations. We aimed to determine the EBV latent infection pattern and frequency of MYC gene aberrations in PBLs. Immunohistochemistry was performed using antibodies for EBNA1, EBNA2, and LMP1 while fluorescence in situ hybridization was performed using a MYC probe. The patient cohort comprised 49 adult cases (44 were HIV-positive and three were HIV-negative). Forty-one cases were EBV-positive with 11 EBNA1-positive cases, all cases EBNA2-negative, and four LMP1-positive cases. Latency 0 was determined in 29 cases, latency I in eight cases, and latency II in four cases. The MYC gene was rearranged in eight cases, showed copy number alterations in 11 cases and, no rearrangement in 11 cases. This is the largest cohort of PBLs from South Africa to show a predominantly restricted EBV latency pattern with MYC gene aberrations as a common finding.

Genome-wide identification and expression analysis of the MYC transcription factor family and its response to sulfur stress in cabbage (Brassica oleracea L.).

MYC transcriptional factors are members of the bHLH (basic helix-loop-helix) superfamily, and play important roles in plant growth, biological and abiotic stress. Recent studies have revealed that some MYCs are involved in the synthesis of sulfur-containing secondary metabolites. Cabbage, as a typical sulfur-loving crop and rich in sulfur-containing secondary metabolites, the regulatory relationship between sulfur stress and MYC gene family, related reports are relatively rare. In this study, we conducted the first genome-wide analysis of the MYC transcription factor family of cabbage and identified 17 BoMYC genes. Homology of the 17 BoMYC genes, 12 Arabidopsis, 12 Chinese cabbage, 8 wheat and 21 maize MYC were analyzed using the phylogenetic analysis. Meanwhile, chromosome locations, physical and chemical characteristics, gene structures, conserved motif, cis-element, specific expression in different tissues were studied. Finally, we analyzed the expression of the BoMYC gene under sulfur stress and its GO annotation and KEGG enrichment analysis, determined the expression of the BoMYC gene under hormone treatment and the growth index, photosynthetic capacity and hormone content in the leaves. This study is of great significance for functional identification and revealed the effect of S on BoMYC transcription factors.

Proteomic characteristics and identification of PM2.5-induced differentially expressed proteins in hepatocytes and c-Myc silenced hepatocytes.

Proteomics and bioinformatics were applied to explore PM2.5-induced differentially expressed proteins (DEPs) in hepatocytes (L02 cells) and c-Myc-silenced hepatocytes. L02 cells and c-Myc-silenced hepatocytes were treated with PM2.5 for 24 h. Fifty-two DEPs were screened in L02 hepatocytes, of which 28 were upregulated and 24 were downregulated. Forty-one DEPs were screened in the c-Myc-silenced hepatocytes, of which 31 were upregulated and 10 were downregulated. GO analysis showed that DEPs in L02 cells were mainly concentrated in the cytosol and were involved in biological processes such as the response to metal ions. DEPs in c-Myc-silenced cells were mainly enriched in the extracellular space and were involved in lipoprotein metabolism. KEGG analysis showed that DEPs in L02 cells were mainly involved in arachidonic acid metabolism and mineral absorption. DEPs in c-Myc-silenced cells were mainly enriched in pathways involving nerve absorption, complement and coagulation cascades, and other pathways. Twenty key proteins, including Metallothionein-2A (MT2A), Metallothionein-1X (MT1X), zinc transporter ZIP10 (SLC39A10) and Serine protease 23 (PRSS23) were screened in two groups through analysis of protein-protein interactions. Based on the identification of the selected DEPs, PRSS23 and SLC39A10 might be the potential biomarker of PM2.5-induced carcinogenesis, which provide the scientific basis for further research into the carcinogenic mechanisms of PM2.5.

MYC status in HIV-associated plasmablastic lymphoma: dual-colour CISH, FISH and immunohistochemistry.

AIMS: We utilised chromogenic and fluorescence in-situ hybridisation (CISH and FISH) to evaluate MYC gene copy numbers and rearrangements within HIV-associated plasmablastic lymphomas (PBLs). Thereafter, clinicopathological features were explored retrospectively. METHODS AND RESULTS: Sixty-seven (n = 67) patients were included and the HIV seropositive status was confirmed in 98% (63 of 64) with a median viral load of 55 587 (IQR 273 582) copies/ml and median CD4 count of 170 (IQR 249) cells/µl. The mean age was 41 ± 10.1 years and females comprised 54%. PBL was documented predominantly at extra-oronasal topographic regions. Starry-sky (SS) appearance was evident in 33% in association with monomorphic morphology (P-value 0.02). c-MYC protein was expressed in 81% and latent EBV infection was detected in 90%. EBER ISH-positive status and MYC rearrangement occurred in 67% of HIV PBL. MYC aberrations included MYC rearrangement (70%), low-level increase in MYC gene copy numbers (43%), concurrent MYC rearrangement and increased MYC gene copy numbers (49%) as well as low-level chromosome 8 polysomy (6%). MYC aberrations in HIV PBLs were significantly associated with SS appearance (P -0.01), monomorphic morphology (P - 0.03), c-MYC protein expression ≥40% (P - 0.03) and mortality (P - 0.03). There was advanced stage (Ann Arbor III/IV) at presentation (77%) and the median overall survival for HIV PBL was 75 days (95% CI 14-136). CONCLUSION: Majority of the HIV-associated PBL tumours harbour MYC aberrations. Due to the persistently inferior survival outcome of HIV-associated PBL in the era of antiviral treatment, targeted and/or intensified therapy of oncogenic MYC may need to be explored in future.

MYC Up-regulation Is a Useful Biomarker for Preoperative Neoadjuvant Chemotherapy Combined With Anti-EGFR in Liver Metastasis from Colorectal Cancer.

BACKGROUND/AIM: At present, there are no biomarkers to predict the effects of molecular targeted drugs in patients with CRC with liver metastasis. Thus, we performed this study to explore potential biomarkers for these patients. MATERIALS AND METHODS: We obtained cancer tissue specimens from liver metastasis-bearing CRC patients who received the following preoperative neoadjuvant chemotherapies with molecular targeted drugs: i) no therapy (n=3), ii) 5-FU+oxaliplatin+anti-EGFR (n=3), iii) and 5-FU+oxaliplatin+anti-VEGF (n=3). RESULTS: We investigated the RNA expression of 84 genes related to cancer drug resistance using an RT-PCR array. The MYC gene was the only gene that was significantly up-regulated in CRC tissue specimens from anti-EGFR group in comparison to the anti-VEGF group. CONCLUSION: MYC up-regulation in the primary CRC tissues may be a potentially useful biomarker for selecting anti-EGFR combination therapy in neoadjuvant chemotherapy for CRC with liver metastasis.

More Insights on the Use of γ-Secretase Inhibitors in Cancer Treatment.

The NOTCH1 gene encodes a transmembrane receptor protein with activating mutations observed in many T-cell acute lymphoblastic leukemias (T-ALLs) and lymphomas, as well as in other tumor types, which has led to interest in inhibiting NOTCH1 signaling as a therapeutic target in cancer. Several classes of Notch inhibitors have been developed, including monoclonal antibodies against NOTCH receptors or ligands, decoys, blocking peptides, and γ-secretase inhibitors (GSIs). GSIs block a critical proteolytic step in NOTCH activation and are the most widely studied. Current treatments with GSIs have not successfully passed clinical trials because of side effects that limit the maximum tolerable dose. Multiple γ-secretase-cleavage substrates may be involved in carcinogenesis, indicating that there may be other targets for GSIs. Resistance mechanisms may include PTEN inactivation, mutations involving FBXW7, or constitutive MYC expression conferring independence from NOTCH1 inactivation. Recent studies have suggested that selective targeting γ-secretase may offer an improved efficacy and toxicity profile over the effects caused by broad-spectrum GSIs. Understanding the mechanism of GSI-induced cell death and the ability to accurately identify patients based on the activity of the pathway will improve the response to GSI and support further investigation of such compounds for the rational design of anti-NOTCH1 therapies for the treatment of T-ALL. IMPLICATIONS FOR PRACTICE: γ-secretase has been proposed as a therapeutic target in numerous human conditions, including cancer. A better understanding of the structure and function of the γ-secretase inhibitor (GSI) would help to develop safe and effective γ-secretase-based therapies. The ability to accurately identify patients based on the activity of the pathway could improve the response to GSI therapy for the treatment of cancer. Toward these ends, this study focused on γ-secretase inhibitors as a potential therapeutic target for the design of anti-NOTCH1 therapies for the treatment of T-cell acute lymphoblastic leukemias and lymphomas.

Effect of Palmatine Binding to MYC G-quadruplex on Proliferation and Apoptosis of Colon Cancer Cells and Molecular Mechanism / 中国实验方剂学杂志

Objective:To explore whether palmatine interferes with the proliferation and apoptosis of colon cancer HCT116 cells by binding to G-quadruplex in the promoter region of MYC proto-oncogene and its possible molecular mechanism. Method:Fluorescence spectrum was used to analyze the binding ability of palmatine to MYC G-quadruplex. Circular dichroism analysis was conducted to confirm the effect of palmatine on the configuration of MYC G-quadruplex， followed by the prediction of their binding mode based on molecular docking and the localization analysis of palmatine in HCT116 cells under a fluorescence microscope. The effects of palmatine on MYC gene transcription and MYC protein expression were determined by real-time fluorescence quantitative polymerase chain reaction and Western blot， respectively. The effects of palmatine on the viability and apoptosis of HCT116 cells were further assayed by thiazolyl blue tetrazolium bromide （MTT） assay and flow cytometry. Result:As revealed by fluorescence spectrum and molecular docking analysis， palmatine might bind to G-quadruplex of MYC gene through stacking. Circular dichroism analysis showed that palmatine could maintain the parallel configuration of MYC<italic> </italic>G-quadruplex. It was discovered in fluorescence imaging that palmatine was distributed in the nucleus and bond to G-quadruplex of MYC gene. In addition， palmatine inhibited MYC gene transcription， MYC protein expression， as well as the viability of HCT116 cells， and promoted the apoptosis of HCT116 cells. Conclusion:Palmatine is able to bind to MYC G-quadruplex to further inhibit the expression of MYC gene and protein expression， which may be one of the molecular mechanisms of palmatine in suppressing the proliferation of colon cancer HCT116 cells and facilitating their apoptosis.

Association between the CEBPA and c-MYC genes expression levels and acute myeloid leukemia pathogenesis and development.

CEBPA and c-MYC genes belong to TF and play an essential role in hematologic malignancies development. Furthermore, these genes also co-regulate with RUNX1 and lead to bone marrow differentiation and may contribute to the leukemic transformation. Understanding the function and full characteristics of selected genes in the group of patients with AML can be helpful in assessing prognosis, and their usefulness as prognostic factors can be revealed. The aim of the study was to evaluate CEBPA and c-MYC mRNA expression level and to seek their association with demographical and clinical features of AML patients such as: age, gender, FAB classification, mortality or leukemia cell karyotype. Obtained results were also correlated with the expression level of the RUNX gene family. To assess of relative gene expression level the qPCR method was used. The expression levels of CEBPA and c-MYC gene varied among patients. Neither CEBPA nor c-MYC expression levels differed significantly between women and men (p=0.8325 and p=0.1698, respectively). No statistically significant correlation between age at the time of diagnosis and expression of CEBPA (p=0.4314) or c-MYC (p=0.9524) was stated. There were no significant associations between relative CEBPA (p=0.4247) or c-MYC (p=0.4655) expression level and FAB subtype and mortality among the enrolled patients (p=0.5858 and p=0.8437, respectively). However, it was observed that c-MYC and RUNX1 expression levels were significantly positively correlated (rS=0.328, p=0.0411). Overall, AML pathogenesis involves a complex interaction among CEBPA, c-MYC and RUNX family genes.

Anti-cancer activity of benzoxazinone derivatives via targeting c-Myc G-quadruplex structure.

AIMS: This study aimed to analyze the impact of four synthesized benzoxazinone derivatives as screening drugs on c-Myc-overexpressed cancer cells (H7402, HeLa, SK-RC-42, SGC7901, and A549) and to explore their interaction mechanisms in detail. MATERIALS AND METHODS: Using morphological analysis, real-time cytotoxicity analysis, wound healing assay, reverse transcription PCR, electrophoretic mobility shift assay, and circular dichroism spectroscopy techniques. KEY FINDINGS: Results revealed that these four compounds could inhibit proliferation of SK-RC-42, SGC7901, and A549 cells in five cancer cell lines to varying degrees and significantly hinder migration. More importantly, the RT-PCR assay showed that the compounds could surprisingly downregulate the expression of c-Myc mRNA in a dose-dependent manner in the five cancer cells, which may be one of the causes of cancer cell proliferation in vitro inhibition. Further EMSA assays demonstrated that at the molecular level of DNA, four compounds can induce the formation of G-quadruplexes (G4-DNAs) in the c-Myc gene promoter. In addition, the CD result of compound 1 clearly indicates that it specifically induces a c-Myc GC-rich 36mer double-stranded DNA in the c-Myc promoter to form a G-quadruplex hybrid configuration. In conclusion, the compounds studied could dose-dependently inhibit the growth and migration of the cancer cells being investigated. This is positively associated with the reduction of overexpression of the c-Myc gene, which may be significantly regulated by the association of compounds with the G-quadruplexes produced in the c-Myc gene promoter region. SIGNIFICANCE: We conclude that three compounds merit further study, particularly against non-small-cell lung cancer, as leading compounds of anticancer drugs.

Evaluation of Myc Gene Expression as a Preventive Marker for Increasing the Implantation Success in the Infertile Women.

BACKGROUND: There are numerous couples worldwide currently suffering from infertility. Several factors, including genetic abnormalities are involved in infertility. In this study, we investigated the expression of myc gene in uterine tissue of infertile women. The protein encoded by this gene is one of the important transcription factors involved in the expression of many genes in the embryonic growth, and development pathways. METHODS: There are about 45 samples of uterine tissue from women with primary and secondary infertility were involved in this study. After extracting RNA and synthesizing cDNA, using specific primers for the myc gene and the beta-actin gene (as an internal control), gene expression was evaluated by Real-time RT-PCR method. RESULTS: The results of myc gene expression analysis showed no significant pattern between the affected and healthy women, however decreasing of its expression should not be rejected. CONCLUSIONS: This study is the first report about myc gene expression and its relation with the primary and secondary infertility. Myc gene expression study at different times of sexual period of infertile woman is suggested. Also, we proposed here, as a preventive strategy, improvement of the expression level of myc gene by some methods, such as hormone therapy, can increase the implantation success in the infertile women.

Malignant transformation in a Breast Adenomyoepithelioma Caused by Amplification of c-MYC: A Common pathway to Cancer in a Rare Entity.

Breast adenomyoepitheliomas are composed of a biphasic proliferation of myoepithelial cells around small epithelial-lined spaces. Due to the rarity of adenomyoepitheliomas, the molecular data describing them are limited. Adenomyoepitheliomas are considered to be benign or have low malignant potential, and be prone to local recurrence. Malignant transformation has been associated with homozygous deletion of CDKN2A or somatic mutations in TERT, but remains unexplained in many cases. Here, we describe a case of carcinomatous transformation of both epithelial and myoepithelial cells in an estrogen receptor-negative adenomyoepithelioma caused by amplification of MYC. Break-apart fluorescence in situ hybridization revealed an increase in the MYC gene copy number (3-4 copies/cell in 37%, > 4 copies/cell in 40%). Deregulation of MYC is responsible for uncontrolled proliferation and cellular immortalization in basal-like breast cancers. Our case demonstrates that genomic instability events associated with gene amplification may be involved in the carcinogenesis of malignant adenomyoepitheliomas.

Characterization of basal and estrogen-regulated antisense transcription in breast cancer cells: Role in regulating sense transcription.

Estrogen-responsive breast cancer cells exhibit both basal and estrogen-regulated transcriptional programs, which lead to the transcription of many different transcription units (i.e., genes), including those that produce coding and non-coding sense (e.g., mRNA, lncRNA) and antisense (i.e., asRNA) transcripts. We have previously characterized the global basal and estrogen-regulated transcriptomes in estrogen receptor alpha (ERα)-positive MCF-7 breast cancer cells. Herein, we have mined genomic data to define three classes of antisense transcription in MCF-7 cells based on where their antisense transcription termination sites reside relative to their cognate sense mRNA and lncRNA genes. These three classes differ in their response to estrogen treatment, the enrichment of a number of genomic features associated with active promoters (H3K4me3, RNA polymerase II, open chromatin architecture), and the biological functions of their cognate sense genes as analyzed by DAVID gene ontology. We further characterized two estrogen-regulated antisense transcripts arising from the MYC gene in MCF-7 cells, showing that these antisense transcripts are 5'-capped, 3'-polyadenylated, and localized to different compartments of the cell. Together, our analyses have revealed distinct classes of antisense transcription correlated to different biological processes and response to estrogen stimulation, uncovering another layer of hormone-regulated gene regulation.

[Correct use of Kreatech DNA probes to detect MYC gene amplification in medulloblastomas by fluorescence in situ hybridization]. / Korrektnoe ispol'zovanie DNK-zondov Kreatech dlia vyiavleniia amplifikatsii gena MYC v medulloblastomakh metodom fliuorestsentnoi gibridizatsii in situ.

In most cases, oncogene amplification are prognostic and predictive markers for various tumors, therefore DNA probes are unable to reveal changes in the copy numbers should not be used to diagnose malignant tumors. OBJECTIVE: To comparatively analyze DNA probes from different manufacturers to detect MYC gene amplification in routine practice. MATERIAL AND METHODS: The study material was formalin-fixed paraffin-embedded medulloblastoma fragments from 4 patients, with discrepancies in the results in the detection of MYC gene amplification. RESULTS: MYC gene amplification was determined using DNA probes: Kreatech MYC (8q24)/SE 8, Vysis LSI MYC SO, Vysis CEP 8 (D8Z2) SG, and Zytolight SPEC MYC/CEN 8 Dual Color Probe. The use of the probes Kreatech TERC (3q26)/MYC (8q24)/SE7 Triple-Color probe failed to detect MYC gene amplification; this probe showed a balanced profile of chromosome 8. CONCLUSION: In routine practice, fluorescence in situ hybridization with the DNA probes Kreatech MYC (8q24)/SE 8, Vysis LSI MYC SO, Vysis CEP 8 (D8Z2) SG and Zytolight SPEC MYC/CEN 8 Dual Color Probe can be the method of choice for studying the copy number of the MYC gene. However, the authors strongly recommend that the Kreatech TERC (3q26)/MYC (8q24)/SE7 Triple-Color should not be used for this purpose. In addition, probes for fluorescence in situ hybridization must be necessarily tested in large reference laboratories dealing with one or another area of oncopathology.

A case of acute promyelocytic leukemia variant with derivative chromosome 3 der(3)t(3;8) associated with 8q partial gain.

BACKGROUND: Acute promyelocytic leukemia (APL) is characterized by fusion of PML/RARα genes as a result of t(15;17)(q24;q21). APL is now one of the curable hematological malignancies thanks to molecularly targeted therapies based on all-trans retinoic acid (ATRA) and arsenic trioxide (ATX). Extramedullary (EM) relapse is a rare event in APL, ear involvement being even more infrequent, with only six cases so far described. About 30-35% of patients with newly diagnosed APL have additional cytogenetics abnormalities, whose prognostic significance is still controversial. The most common additional aberration is trisomy 8 or partial gain 8q. CASE PRESENTATION: We describe here a novel unbalanced translocation der(3)t(3;8)(q29;q23.3-q24.3) associated with 8q partial gain in a 41 year-old man affected by APL in molecular remission after first line treatment, who had a responsive EM relapse in the auditory canal. CONCLUSIONS: EM relapse is a rare event in APL and ear involvement is even more infrequent. To our knowledge, this is the first reported case of APL with a new der(3)t(3;8)(q29;q23.3-q24.3) and 8q partial gain associated with t(15;17)(q24;q21). Despite the recurrence of the disease at EM level, the clinical outcome of this patients was favorable.