C-myc Gene Copy Number Research Articles

Importance of Copy Number Alterations of FGFR1 and C-MYC Genes in Triple Negative Breast Cancer.

SummaryBackgroundTriple negative breast cancer (TNBC) is characterized by aggressive clinical course and is unresponsive to anti-HER2 and endocrine therapy. TNBC is difficult to treat and is often lethal. Given the need to find new targets for therapy we explored clinicopathological significance of copy number gain of FGFR1 and c-MYC. Our aim was to determine the impact of FGFR1 and c-MYC copy number gain on clinical course and outcome of TNBC.MethodsFGFR1 and c-MYC gene copy number alterations were evaluated in 78 archive TNBC samples using TaqMan based quantitative real time PCR assays.Results50% of samples had increased c-MYC copy number. c-MYC copy number gain was associated with TNBC in contrast to ER positive cancers. Our results showed significant correlation between c-MYC copy number gain and high grade of TNBCs. This suggests that c-MYC copy number could be an useful prognostic marker for TNBC patients. c-MYC copy number gain was associated with high pTNM stage as well as lobular and medullary tumor subtypes. 43% of samples had increased FGFR1 copy number. No correlations between FGFR1 copy number gain and clinicopathological variables were observed.ConclusionsWe identified c-MYC copy number gain as a prognostic marker for TNBC. Our results indicate that c- MYC may contribute to TNBC progression. We observed no significant association between c-MYC and/or FGFR1 copy number status and patient survival.

Digital polymerase chain reaction for detecting c-MYC copy number gain in tissue and cell-free plasma samples of colorectal cancer patients

We focused on the utility of the droplet digital polymerase chain reaction (ddPCR) for detecting c-MYC gene copy number (GCN) gain in cell-free plasma and tumor tissue of colorectal cancer (CRC) patients. c-MYC GCN status was determined using dual-color silver in situ hybridization (SISH) and ddPCR in retrospective cohort 1 (192 CRC patients) and prospective cohort 2 (64 CRC patients). In cohort 1, c-MYC GCN gain was observed in 34 (17.5%) patients by SISH, and in 7 (3.6%) patients by ddPCR. c-MYC GCN by SISH significantly correlated with ddPCR results (ρ = 0.532, P < 0.001). Although 40 cases (20.7%) showed intratumoral genetic heterogeneity, it did not cause discordance in results obtained by the two methods. c-MYC GCN gain, by both SISH and ddPCR was independently correlated with worst prognosis (P = 0.002). In cohort 2, c-MYC GCN estimation in tissue by ddPCR was also significantly associated with results obtained by SISH (ρ = 0.349, P = 0.005), but correlated with plasma ddPCR with borderline significance (ρ = 0.246, P = 0.050). Additionally, detecting c-MYC GCN gain in plasma with ddPCR might have relatively low sensitivity but high specificity. Our study suggests that ddPCR can be a useful tool for detecting c-MYC GCN gain as a potential prognostic biomarker in CRC tissue samples; however, this will need further verification in plasma samples.

Abstract 642: Comparison between in situ hybridization and digital polymerase chain reaction methods for detecting c-MYC gene copy number gain in tissue and cell-free plasma samples of colorectal cancer patients

Abstract Introduction: We focused on the utility of the droplet digital polymerase chain reaction (ddPCR) for detecting c-MYC gene copy number (GCN) gain in cell-free plasma and tumor tissue of CRC patients. Methods: c-MYC GCN was determined by using dual-color silver in situ hybridization (SISH) and ddPCR in retrospective cohort of 193 CRC patients (cohort 1) and prospective cohort of 64 CRC patients (cohort 2). Additionally, c-MYC GCN was analyzed by ddPCR method in cell-free plasma samples of cohort 2. Results: In cohort 1, c-MYC GCN gain, defined as mean c-MYC copies/nucleus ≥ 4.0 in SISH analysis, was observed in 34 (17.5%), and c-MYC GCN gain by ddPCR method in 7 (3.6%). c-MYC GCN by SISH was significantly correlated with ddPCR results (ρ= 0.532, P &amp;lt; 0.001). Forty cases (20.7%) showed intratumoral genetic heterogeneity, but it did not affect the concordance between SISH and ddPCR results (P &amp;gt; 0.05). c-MYC GCN gain by both SISH and ddPCR methods had the worst prognosis (P = 0.001). In cohort 2, c-MYC GCN by SISH was significantly associated with tissue ddPCR (ρ=0.349, P = 0.005), but not with plasma ddPCR (P = 0.620). Intratumoral genetic and regional heterogeneity of c-MYC status have been found in 29 (45.3%) and 8 (12.7%). c-MYC status in plasma was associated with tissue ddPCR, but borderline statistical significance (ρ= 0.246, P = 0.050). Conclusions: Our findings suggested that results by SISH and ddPCR methods were discordant. Therefore, detecting method should be carefully selected to determine c-MYC GCN status. Citation Format: Soo Hyun Seo, Kyu Sang Lee, Soo Kyung Nam, Kyoung Un Park, Heung-Kwon Oh, Duck-Woo Kim, Sung-Bum Kang, Hye Seung Lee. Comparison between in situ hybridization and digital polymerase chain reaction methods for detecting c-MYC gene copy number gain in tissue and cell-free plasma samples of colorectal cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 642.

Importance of Copy Number Alterations of FGFR1 and C-MYC Genes in Triple Negative Breast Cancer

Summary Background: Triple negative breast cancer (TNBC) is characterized by aggressive clinical course and is unresponsive to anti-HER2 and endocrine therapy. TNBC is difficult to treat and is often lethal. Given the need to find new targets for therapy we explored clinicopathological significance of copy number gain of FGFR1 and c-MYC. Our aim was to determine the impact of FGFR1 and c-MYC copy number gain on clinical course and outcome of TNBC. Methods: FGFR1 and c-MYC gene copy number alterations were evaluated in 78 archive TNBC samples using TaqMan based quantitative real time PCR assays. Results: 50% of samples had increased c-MYC copy number. c-MYC copy number gain was associated with TNBC in contrast to ER positive cancers. Our results showed significant correlation between c-MYC copy number gain and high grade of TNBCs. This suggests that c-MYC copy number could be an useful prognostic marker for TNBC patients. c-MYC copy number gain was associated with high pTNM stage as well as lobular and medullary tumor subtypes. 43% of samples had increased FGFR1 copy number. No correlations between FGFR1 copy number gain and clinicopathological variables were observed. Conclusions: We identified c-MYC copy number gain as a prognostic marker for TNBC. Our results indicate that c- MYC may contribute to TNBC progression. We observed no significant association between c-MYC and/or FGFR1 copy number status and patient survival.

Value of CD, MPO, Ki-67 and C-MYC Positive Rate in the Pathological Tissues and C-MYC Gene of Patients with T-LBL/ALL for Predicting Prognosis

To explore the value of of CD, MPO, Ki-67, C-MYC positive rates in the pathological tissues and C-MYC gene of patients with T-LBL/ALL for predicting Prognosis. Ninty cases of T-LBL/ALL patients in our hospital were selected and included in the T-LBL/ALL group, and 30 cases of lymphnode reactive hyperplasia were selected as control group. Immunohistochemical staining was used to detect the changes of CD, MPO, Ki-67 and C-MYC positive rate in 2 groups, and the changes of C-MYC gene were detected by fluorescence in situ hybridization. In 90 patients with T-LBL/ALL, there were CD1a+ 34 cases (37.8%), CD3+ 67 cases (74.4%), epsilon CD3+ 47 cases (52.2%), CD7+ 85 cases (94.4%), CD10+ 33 cases (36.7%), CD34+ 22 cases (24.4%), CD43+ 48 cases (53.3%), CD45RO+ 46 cases (51.1%), CD99+ 88 cases (97.8%), TDT+ 85 cases (94.4%); and CD23, CD20, and MPO all were negative; Ki-67>80% 47 cases (52.2% cases), Ki-67≤80%, 43 cases (47.8%). In 90 T-LBL/ALL patients, the positive rate of C-MYC (66.7%) was significantly higher than the control group (positive rate 0.0%) (P< 0.05); the Ki-67 index, mediastinal widening of T-LBL/ALL patients and the positive rate of C-MYC positively were correlated (P< 0.05). The overall survival rate (44.0%) of C-MYC negative patients was significantly higher than that of C-MYC positive patients (0.0%). The overall survival rate of C-MYC negative patients was significantly higher than that of C-MYC positive patients (P< 0.05).Ann Arbor staging, LDH, bone marrow involvement, mediastinal widening, Ki-67 positive index, and C-MYC protein expression of patients with T-LBL/ALL did not correlated with increased C-MYC gene breakage and copy number (P> 0.05). The overall survival rate of C-MYC positive patients decreases, which positively correlates with Ki-67 positive index and mediastinal width, suggesting that the prognosis of the patients with C-MYC protein expression is poorer.

C-MYC Gene and Protein Expression in Paraffin Wax of T Lymphoblastic Lymphoma and Leukemia Patients and Its Effect on the Prognosis

To explore the relevance between the expression of C-MYC gene and protein of patients with T lymphoblastic lymphoma and leukemia(T-LBL/ALL) and its effect on the prognosis. Paraffin specimens from 60 cases of T-LBL/ALL with detailed follow-up during May 2005 to May 2016 were selected as study group; at same time 20 cases of reactive hyperplasia (RH) of lymphonuedes were selected as control group. The immunohistochemical EnVision method was used to mark the terminal deoxynucleotidyl transferase (TDT), myeloperoxidase (MPO), Ki-67 and C-MYC immune tissue. C-MYC gene rupture and copy number increase did not occur in 20 cases of RH.The expression of C-MYC protein did not correlate with C-MYC gene copy number increase. The expression rate of C-MYC protein was 66.7% (40/60), and 20 cases of lymph node RH was all negative (0/20), as compared with the positive expression rate of protein C-MYC, the difference was statistically significant (P<0.05). The Ki-67 positive index and mediastinal bloadening had influence on the expression of C-MYC protein (P<0.05), the sex, primary site, symptoms, age, AnnArbor stage and lactate dehydrogenase (LDH) level and bone marrow involvement have no influence on it, there was no statistically significant difference (P>0.05). The 8q24 chromosome breakage occurred in 6 cases (10%), and the number of copies increased in 11 cases (18.3%). C-MYC gene copy number increase and C-MYC gene rupture in a total 20 cases of reactive hyperplasia of lymph nodes did not occur. C-MYC gene may play an important role on the development of T-LBL/ALL. It can be an independent prognosis factor.

Survival of patients with primary central nervous system diffuse large B-cell lymphoma: impact of gene aberrations and protein overexpression of bcl-2 and C-MYC, and selection of chemotherapy regimens

Objective: To investigate the impact of clinicopathological features, gene rearrangements and protein expression of bcl-6, bcl-2, C-MYC and chemotherapy regime on the prognosis of patients with primary central nervous system diffuse large B-cell lymphoma (PCNS-DLBCL). Methods: Thirty-three cases of PCNS-DLBCL diagnosed from January 2006 to December 2016 at Zhejiang Cancer Hospital were collected. The expression of CD10, bcl-6, bcl-2, MUM1 and MYC were detected by immunohistochemical staining (IHC). The presence of EB virus was detected by in situ hybridization(EBER). Copy number variation (ICN) and translocation status of bcl-6, bcl-2 and C-MYC genes were detected by fluorescence in situ hybridization (FISH). The relationship between the above indexes and the prognosis was analyzed by univariate, bivariate survival analysis and multiple Cox hazard regression analysis. Results: The study included 33 patients of PCNS-DLBCL, without evidence of primary or secondary immunodeficient disease. Male to female ratio was 1.36∶1.00, and the average age was 56 years. Twenty cases had single lesion while 13 had multiple lesions. Deep brain involvement was seen in 12 cases. All patients underwent partial or total tumor resection. Five patients received whole brain post-surgery radiotherapy, nine patients received high-dose methotrexate (HD-MTX) based chemotherapy, and 12 patients received whole-brain radiotherapy combined with HD-MTX based chemotherapy. Severn patients received no further treatment and rituximab was used in 8 patients. According to the Hans model, 27 cases were classified as non-GCB subtypes (81.8%). Bcl-2 was positive in 25 cases (75.8%, 25/33) and highly expressed in 8 (24.2%). MYC was positive in 12 cases (36.4%) and double expression of bcl-2 and MYC was seen in 6 cases. EBER positive rate was 10.0%(3/30), all of which had multiple lesions. Two bcl-6 gene translocations and 3 amplifications were found in 28 patients. Two translocations, 3 ICN or with both bcl-2 gene translocation and ICN were found in 30 patients. Four ICNs of C-MYC gene were found in 28 patients. Elevated protein in cerebrospinal fluid (CSF) was found in 13 patients. LDH increased in 10 cases. Follow-up period was 2-90 months with the average survival time of (23.0±3.7) months and two-year survival rate of 39.0%. Univariate survival analysis showed that overexpression of bcl-2 protein (≥70%) and MYC protein (≥40%), bcl-2 gene abnormality (including copy number increase and translocation), C-MYC gene copy number increased were adverse factors for survival. C-MYC/ bcl-2 gene double hit was seen in 2 cases. Bivariate survival analysis found that of bcl-2/MYC protein double expression and bcl-2 and C-MYC genes double aberration were significantly associated with adverse outcomes. Cox multivariate risk regression analysis found that gender, cerebrospinal fluid protein increasing, and ICN of C-MYC gene were independent poor prognostic factors. DH-MTX based comprehensive chemotherapy was associated with better prognosis. Conclusions: Double hit at genomic level (copy number variations and gene rearrangements) and double protein expression of bcl-2 and C-MYC in PCNS-DLBCL are significantly associated with an adverse outcome. DH-MTX based comprehensive treatment may prolong the patient survival.

Expression of C-myc and β-catenin and their correlation in triple negative breast cancer.

The present study was planned to study the expression of C-myc and β-catenin in triple negative breast cancer (TNBC) tissue. Furthermore, their relations to clinical features of the tumor and the survival prognosis were also studied. Additionally, correlation was evaluated between the expression of C-myc and β-catenin to provide the theoretical basis for the targeted therapy of TNBC. Sixty cases of patients diagnosed with TNBC for the first time were selected for the study. The immumo-histochemical staining was employed to detect the positive expression rates of C-myc and β-catenin in cancer tissues and normal mammary tissues 3 cm away from the carcinoma. Fluorescence in situ hybridization (FISH) was used to test the gene amplification of C-myc in order to analyze the relation between C-myc and the protein expression of β-catenin. Further, kept the median follow-up time to 25.0 months in order to compare the survival prognosis. The positive expression rates of C-myc and β-catenin in cancer tissues were significantly higher than those in precancerous normal tissues (P<0.05). Furthermore, the expression rates were related with the diameter of tumor, clinical staging, pathological grading and lymphatic metastasis (P<0.5). There were 33 cases that exhibited an increase in C-myc gene copy number and the gene amplification was observed to be 55% in total. On the other hand, patients with positive expression of C-myc and β-catenin protein exhibited a shortened disease-free survival without tumor with an increasing recurrence rate and lower survival rate (P<0.05). The present study concludes that the positive expression of C-myc and β-catenin in TNBC tissue might be closely correlated with clinical features of cancer and the survival prognosis.

The clinical significance of c-MYC expression, rearrangement, and copy number gain in extranodal NK/T-cell lymphoma: A retrospective study in China

Extranodal NK/T-cell lymphoma (ENKTL), nasal type is an aggressive lymphoma characterized by rapid clinical progression, an unfavorable prognosis, and a short survival time. This study aimed to investigate the correlations of c-MYC protein expression, gene rearrangement, and gene copy number with the prognosis of ENKTL. Immunohistochemistry for CD20, CD3, CD56, TIA-1, Ki-67, and c-MYC were performed using tissue sections from 68 patients diagnosed with ENKTL. In situ hybridization was performed to detect Epstein-Barr virus (EBV)-encoded small RNA (EBER). c-MYC genetic alterations (located on chromosome 8q24) were detected using fluorescence in situ hybridization. Sixty patients with nasopharyngeal mucosa lymphadenosis were selected as a normal control group for the c-MYC gene and protein. Immunophenotypically, CD3 and TIA-1 were positive in all patients, CD56 was positive in 54 patients (79.4%), and CD20 was negative in all patients. A Ki-67 proliferation index of >50% was observed in 94.1% of patients (64/68). In situ hybridization for EBER was positive in all patients. The c-MYC positive expression rate (>40% of tumor cells with nuclear staining regarded as positive) in patients with ENKTL was 50% (34/68), which was significantly higher than that in patients with nasopharyngeal mucosa lymphadenosis (0%, 0/60; p<0.05). Treatment efficacy was poor in patients with high c-MYC protein expression (p<0.05). Genetically, c-MYC rearrangements were not detected in any patients, but 26.5% (18/68) had increased c-MYC copy numbers. The gain of c-MYC copy numbers was positively correlated with c-MYC protein expression (p<0.05). Kaplan-Meier analysis illustrated that overall survival was significantly shorter in the c-MYC-positive group than in the c-MYC-negative group (p<0.05). Gain of c-MYC copy numbers was not associated with prognosis (p>0.05). Multivariate Cox regression analysis further confirmed that clinical stage and c-MYC positivity were independent prognostic factors in patients with ENKTL. The abnormal expression of c-MYC may play an important role in the development and progression of ENKTL and influence the prognosis of patients.

C-myc Gene Copy Number Variation in Cervical Exfoliated Cells Detected on Fluorescence in situ Hybridization for Cervical Cancer Screening

Purpose: This study assessed the clinical significance of c-myc gene copy number gain detected by fluorescence in situ hybridization (FISH) in the prediction of cervical intraepithelial neoplasia (CIN) progression. Methods: We retrospectively investigated 140 Thinprep cytologic test (TCT) specimens that were histopathologically diagnosed with various stages of cervical neoplasia or malignancy. The specimens were subjected to TCT, human papillomavirus (HPV) testing, and FISH analysis with a c-myc-specific probe. The diagnostic reliability of these methods in determining progression was assessed according to sensitivity, specificity, and κ coefficients. Results: The gene copy number gain of c-myc was significantly higher in the cervical lesion of advanced histologic grade (p < 0.001). For CIN2+ lesions, the sensitivities of TCT, HPV DNA testing, and FISH analysis were 72.3, 92.1, and 64.5%, respectively; the specificities were 81.3, 57.8, and 93.8%, respectively (p < 0.001). The κ coefficients between the c-myc gene test and either the TCT or the HPV DNA test were 0.538 and 0.399, respectively (p < 0.001). Conclusions: FISH analysis of the c-myc oncogene could be a useful adjunct screening method for the early diagnosis of high-grade cervical lesions. Moreover, c-myc may be a new molecular biomarker for the early diagnosis of cervical lesion progression.

C-MYC Copy-Number Gain Is an Independent Prognostic Factor in Patients with Colorectal Cancer.

BackgroundThe aim of this study was to determine the incidence and clinicopathological significance of c-MYC gene copy-number (GCN) gain in patients with primary colorectal cancer (CRC).MethodsThe c-MYC GCN was investigated in 367 consecutive CRC patients (cohort 1) by using dual-color silver in situ hybridization. Additionally, to evaluate regional heterogeneity, we examined CRC tissue from 3 sites including the primary cancer, distant metastasis, and lymph-node metastasis in 152 advanced CRC patients (cohort 2). KRAS exons 2 and 3 were investigated for mutations.ResultsIn cohort 1, c-MYC gene amplification, defined by a c-MYC:centromere of chromosome 8 ratio ≥ 2.0, was detected in 31 (8.4%) of 367 patients. A c-MYC GCN gain, defined by ≥ 4.0 c-MYC copies/nucleus, was found in 63 (17.2%) patients and was associated with poor prognosis (P = 0.015). Multivariate Cox regression analysis showed that the hazard ratio for c-MYC GCN gain was 2.35 (95% confidence interval, 1.453–3.802; P < 0.001). In a subgroup of stage II-III CRC patients, c-MYC GCN gain was significantly associated with poor prognosis by univariate (P = 0.034) and multivariate (P = 0.040) analyses. c-MYC protein overexpression was observed in 201 (54.8%) out of 367 patients and weakly correlated with c-MYC GCN gain (ρ, 0.211). In cohort 2, the c-MYC genetic status was heterogenous in advanced CRC patients. Discordance between GCN gain in the primary tumor and either distant or lymph-node metastasis was 25.7% and 30.4%, respectively. A similar frequency for c-MYC GCN gain and amplification was observed in CRC patients with both wild-type and mutated KRAS.Conclusions c-MYC GCN gain was an independent factor for poor prognosis in consecutive CRC patients and in the stage II-III subgroup. Our findings indicate that the status of c-MYC may be helpful in predicting the patients’ outcome and for managing CRC patients.

468 Clinicopathologic implication of c-MYC gene copy number gain and overexpression in colorectal cancer

468 Clinicopathologic implication of c-MYC gene copy number gain and overexpression in colorectal cancer

Abstract P3-06-12: Effect of TOP2A and cMYC gene copy number on outcome in a Phase II trial of adjuvant TC (Docetaxel/Cyclophosphamide) plus trastuzumab (HER TC) in HER2-positive early stage breast cancer

Abstract Introduction: Approximately one-third of HER2+ early stage breast cancer (ESBC) patients have TOP2A-amplified breast cancer, the subpopulation known to benefit from anthracycline use (Press et al, JCO 2011). Data are needed to evaluate whether outcomes in ESBC patients treated with nonanthracycline-based regimens like docetaxel and cyclophosphamide + trastuzumab (HER TC) are affected by TOP2A or cMYC gene copy number. Methods: This was an open-label, phase II study of HER TC in HER2+ breast cancer patients. Outcome data have been previously reported (Jones et al, SABCS 2011, PD07-03). Tissue was collected to review HER2, cMYC, and TOP2A gene copy number at a central reference laboratory. HER2, cMYC, and TOP2A amplification was defined as FISH ratio &amp;gt;2, and deletion was defined as FISH ratio &amp;lt;1. Every 21 days, patients received T 75mg/m2 IV and C 600mg/m2 IV, plus weekly H 4mg/kg IV (loading dose) and 2mg/kg IV thereafter for a total of 4 cycles. After 4 cycles of TC+H, patients continued on H for 1 year on a 3-week schedule. The primary endpoint was disease-free survival (DFS) at 2 years with continued follow-up for 3 years. Secondary endpoints were overall survival (OS) and safety. Results: 493 patients with HER2+ ESBC were enrolled. From the 493 patients, 438 (89%) tissue samples were available and analyzed at Caris Diagnostics (Phoenix, AZ) to test for TOP2A, cMYC, and HER2 gene copy number by FISH. HER2 status was confirmed as positive in 87% of samples. Results for TOP2A, cMYC, and HER2 were generated in 438, 436, and 438 samples, respectively. TOP2A was classified as amplified in 43%, normal in 30%, deleted in 27%. cMYC was classified as amplified in 99(23%), normal in 246(56%), and deleted in 91(21%). Three-year DFS and OS in TOP2A and cMYC status as well as ER and Nodal status are depicted in Table 1. Multivariate analyses of age, nodal status, ER status, and gene expression shown below in Table 2 indicate that neither cMYC nor TOP2A status had an effect on outcome. Only nodal and ER status affected outcome. Conclusion: Outcome (DFS + OS) in a phase II study of a nonanthracycline regimen (TC) coupled with H was unaffected by cMYC or TOP2A gene copy number status. Only ER and nodal status showed an effect in a multivariate analysis. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P3-06-12.

29. c-MYC gene amplification is associated with a poor prognosis in invasive ductal carcinoma

Background c-MYC is a proto-oncogene located on 8q24 with well-established critical roles in the development and progression of breast cancer. However, there is relatively little information available on the frequency of its amplification in breast cancer, with widely varying estimates in the literature and only two studies using the gold-standard of fluorescent in situ hybridisation (FISH). Moreover, there is little consensus as to a clinically relevant c-MYC/CEP8 (centromeric region of chromosome 8) ratio in determining patient outcome or response to therapy. Methods We investigated the frequency of c-MYC gene amplification using FISH in formalin fixed, paraffin processed tissues in 16 tissue microarrays from a cohort of 262 patients with operable invasive ductal carcinoma. C-MYC gene and CEP8 region copy number were determined in 20 representative tumour nuclei and a ratio c-MYC/CEP8 calculated. Two different ratios were tested using Kaplan-Meier survival analysis for their prognostic strength; 2.2 as used to determine HER2 gene amplification, and a newly described ratio of 1.3 which co-segregated with outcome. Chi squared analysis was then used to investigate the clinicopathological associations of c-MYC gene amplification Results A c-MYC/CEP8 ratio of 1.3 identified a poor prognostic group in the cohort (HR 2.28, p = 14; 0.006), while a ratio of 2.2 showed only a trend towards significance (p = 14; 0.087). Using a ratio of 1.3, 22.1% of cancers showed c-MYC gene amplification, while 61% were diploid and 16.9% were polysomic. c-MYC gene amplification was associated with larger, grade 3, ER negative, Ki67 high tumours (all p 5 0.05). Furthermore there was a highly significant association with the basal-like phenotype (p = 14; 0.004). Conclusion We have validated that a c-MYC/CEP8 ratio of 1.3 is able to identify a poor prognosis group of breast cancer patients. c-MYC gene amplification is associated with a number of high risk clinicopathological variables.

C -MYC amplification and expression in astrocytic tumors

The aim of this study was to evaluate the nuclear and cytoplasmic expression of c-MYC protein in human astrocytic tumors of different histopathological grades and to determine whether its expression correlates with c-MYC gene amplification. An immunohistochemical study of c-MYC protein was performed in 140 paraffin-embedded astrocytic tumors of different grades. Among them, 30 specimens were analyzed for c-MYC gene amplification by FISH. Expression of nuclear and cytoplasmic c-MYC was observed, respectively, in 65.0 and 66.4% of the cases studied. The distribution of the positive cases according to the tumor grade increased in both nuclear and cytoplasmic staining with malignancy. The median nuclear LI also increased with tumor grade, with highest c-MYC nuclear expression in grade III. The median cytoplasmic labeling scores showed a significant difference between grade I tumors and diffuse tumors, which presented high and similar median scores. Cytoplasmic c-MYC localization was linked to high nuclear c-MYC expression. FISH results disclosed that the presence of two signals was inversely correlated with histopathological grade, while the presence of >/=5 signals increased according to degree of malignancy. Moreover, the presence of two signals was associated with low nuclear LI and the presence of four or more signals with high nuclear LI. These results indicate that c-MYC expression in astrocytic tumors is strongly associated with increased c-MYC gene copy number and suggest that c-MYC plays a role in the early tumorigenesis of astrocytomas.

Relationship between chromosome 8 alterations and Gleason score in prostatic adenocarcinoma

To study the gain of chromosome 8 and c-myc gene and lipoprotein lipase gene status in prostatic adenocarcinoma of Chinese patients, and to analyze the relationship between chromosome 8 alterations and Gleason score of prostatic cancer. Formalin-fixed, paraffin-embedded prostatic biopsy tissues from 34 Chinese patients with untreated prostatic adenocarcinoma were studied by three-color fluorescence in situ hybridization (FISH) using ProVysion(TM) probe kit. The materials included 1 case with Gleason score 5, 10 cases with Gleason score 6, 14 cases with Gleason score 7, 4 cases with Gleason score 8 and 5 cases with Gleason score 9. The relationship between Gleason score and chromosome 8 aneusomy, c-myc and lipoprotein lipase gene copy number, including gene amplification or deletion, were analyzed. Seventeen (50%) of the 34 cases studied had gain of chromosome 8, while 21 cases (61.8%) had gain of c-myc gene copy number, 15 cases (44.1%) had lipoprotein lipase gene monosomy, 23 cases (67.6%) had c-myc gene amplification, 21 cases (61.8%) had deletion of lipoprotein lipase gene and 16 cases (47.1%) had lipoprotein lipase gene deletion coupled with c-myc gene amplification. In general, at least one type of chromosome 8 alteration was identified in 85.3% of cases (29/34). Gain of chromosome 8 was strong significant associated with Gleason score (P = 0.0006). A positive correlation between increased c-myc copy number and high Gleason score was also noted (P = 0.0035). On the other hand, loss of lipoprotein lipase gene was negatively correlated with high Gleason score (P = 0.0383). In addition, the association of c-myc gene amplification with high Gleason score was noted after age adjustment (P = 0.0462). Alterations in chromosome 8 are common in prostatic adenocarcinoma occurring in Chinese patients. There is a correlation between Gleason score and gain of chromosome 8, increased c-myc gene copy number, c-myc gene amplification and lipoprotein lipase gene deletion. C-myc gene amplification accompanied by lipoprotein lipase gene deletion is also a common occurrence in prostatic cancer. Our data suggest that chromosome 8 alterations may play some roles in the development and progression of prostatic adenocarcinoma.

C-myc Amplifications in primary breast carcinomas and their local recurrences

Objective: To evaluate the role of c-myc oncogene amplifications in the progression of invasive breast carcinomas. Methods: c-myc gene copy number was evaluated in a series of 49 primary breast...

Correlations between c-myc gene copy-number and clinicopathological parameters of ovarian tumours

The objective of this study was to investigate increases in c-myc gene copy-number in ovarian tumours, and to analyze their correlations with clinicopathological parameters. Here we applied FISH on TMA (tissue microarrays) containing 507 ovarian tumour samples from different malignancy, histology, stage and grade. Overall, we found high frequency for c-myc copy-number increases (38.5%) in ovarian cancers: 22.1% amplifications and 16.4% gains. We established c-myc amplification in more than 30% in endometrioid and mixed epithelial ovarian carcinomas. c-myc gains were found in a high proportion (42.9%) of clear cell carcinomas. We found associations between c-myc copy-number changes and clinicopathological parameters of ovarian tumours such as degree of malignancy and histological type. We suggested that c-myc amplifications are characteristics for endometrioid, and c-myc gains for clear cell ovarian cancers. We suggest that copy-number increases of c-myc and 20q13.2 represent a possible mechanism for the regulation of the pathway STK15--c-myc--hTERT.

High‐throughput tissue microarray analysis of CMYC amplificationin urinary bladder cancer

Alterations of chromosome 8, preferentially deletions of 8p and gains of 8q, belong to the most frequent cytogenetic changes in bladder cancer. CMYC on 8q24 is a candidate oncogene in this region. Little is known about the clinical significance of CMYC copy number changes in urinary bladder cancer because its frequency is low and a limited numbers of tumors were analyzed so far. To investigate the impact of CMYC alterations on tumor progression and patient prognosis in bladder cancer, we applied FISH to a tissue microarray containing 2317 bladder cancer samples. Presence of CMYC copy number increase was associated with advanced stage and high grade. CMYC amplifications were seen in 3 of 467 pTa (0.6%), 10 of 247 pT1 (4%) and 11 of 201 pT2-4 urothelial carcinomas (5.5%; p < 0.0001), as well as in 1 of 123 G1 (0.8%), 8 of 470 G2 (1.7%) and 17 of 365 G3 urothelial carcinomas (4.7%; p < 0.0001). CMYC gains were present in 49 of 467 pTa (10.5%), 39 of 247 pT1 (15.8%) and 43 of 201 pT2-4 urothelial carcinoma (21.4%; p < 0.0001), as well as in 7 of 123 G1 (5.7%), 56 of 470 G2 (11.9%) and 72 of 365 G3 urothelial carcinomas (19.7%; p < 0.0001). CMYC copy number changes were unrelated to prognosis of bladder cancer patients. We conclude that alterations of the CMYC gene, including copy number gains and amplifications, are linked to genetically unstable bladder cancers that are characterized by a high histologic grade and/or invasive growth. Patient prognosis was not affected by CMYC gene copy number changes.

C‐MYC expression in medulloblastoma and its prognostic value

To identify prognostic factors in medulloblastoma, a common malignant brain tumor of childhood, expression of the oncogene c-myc was examined at the mRNA level by in situ hybridization. c-myc mRNA expression was observed in 30 of 72 tumors (42%). The c-myc gene copy number was determined by quantitative PCR from genomic DNA of paraffin-embedded tumors. c-myc gene amplification was present in 5 of 62 cases (8.3%). Therefore, c-myc amplification was obviously not the cause of c-myc mRNA expression in most samples. Kaplan-Meier estimation revealed a significant correlation between c-myc mRNA expression and survival (total mean follow-up 4.6 ± 3.6 years, log-rank p = 0.02). Multivariate logistic regression analysis including sex, age, histological type, degree of surgical resection and expression of synaptophysin, GFAP and c-myc, was carried out on 54 patients who received both radiotherapy and chemotherapy. The analysis identified expression of c-myc as an independent predictive factor of death from disease. Int. J. Cancer 89:395–402, 2000. © 2000 Wiley-Liss, Inc.