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PDF file 1687K, The supplementary data contains immunostains, mRNA and DNA qPCR, ELISA analyses and descriptive cartoons including a model highlighting the manuscript

PDF file 145K, Tables containing information about genes residing on the amplicon and compiled data

Breast cancers exhibit intratumoral heterogeneity associated with disease progression and therapeutic resistance. To define the sources and the extent of heterogeneity, we performed an in-depth analysis of the genomic architecture of three chemoradiation-naïve breast cancers with well-defined clinical features including variable ER, PR, ERBB2 receptor expression and two distinct pathogenic BRCA2mut genotypes. The latter included a germ line carrier and a patient with a somatic variant. In each case we combined DNA content-based flow cytometry with whole exome sequencing and genome wide copy number variant (CNV) analysis of distinct populations sorted from multiple (4–18) mapped biopsies within the tumors and involved lymph nodes. Interrogating flow-sorted tumor populations from each biopsy provided an objective method to distinguish fixed and variable genomic lesions in each tumor. Notably we show that tumors exploit CNVs to fix mutations and deletions in distinct populations throughout each tumor. The identification of fixed genomic lesions that are shared or unique within each tumor, has broad implications for the study of tumor heterogeneity including the presence of tumor markers and therapeutic targets, and of candidate neoepitopes in breast and other solid tumors that can advance more effective treatment and clinical management of patients with disease.

The amplification of chromosome 9p24.1 encoding PD-L1, PD-L2, and JAK2 has been reported in multiple types of cancer and is associated with poor outcome, upregulation of PD-L1, and activation of the JAK/STAT pathway. We have developed a novel fluorescence in situ hybridization assay which combines 3 probes mapping to 9p24.1 with a commercial chromosome 9 centromere (CEN9) probe for detection of the JAK2/9p24.1 amplification. JAK2 fluorescence in situ hybridization was compared with array-based comparative genomic hybridization in 34 samples of triple negative breast cancer tumor. By array-based comparative genomic hybridization, 15 had 9p24.1 copy-number gain (log2ratio>0.3) and 19 were classified as non-gain (log2ratio≤0.3). Copy-number gain was defined as JAK2/CEN9 ratio ≥1.1 or average JAK2 signals≥3.0. Twelve of 15 samples with copy-number gain by array-based comparative genomic hybridization were also detected by fluorescence in situ hybridization. Eighteen of 19 samples classified as copy-number non-gain by array-based comparative genomic hybridization were concordant by array-based comparative genomic hybridization. The sensitivity and specificity of the fluorescence in situ hybridization assay was 80% and 95%, respectively (P=0.02). The sample with the highest level of amplification by array-based comparative genomic hybridization (log2ratio=3.6) also scored highest by fluorescence in situ hybridization (ratio=8.2). There was a correlation between the expression of JAK2 and amplification status (Mean 633 vs 393, P=0.02), and there was a trend of association with PD-L1 RNA expression (Mean 46 vs 22, P=0.11). No significant association was observed between PD-L1 immunohistochemistry expression and copy-number gain status. In summary, the novel array-based comparative genomic hybridization assay for detection of chromosome 9p24.1 strongly correlates with the detection of copy-number gain by array-based comparative genomic hybridization. In triple negative breast cancer, this biomarker may identify a relevant subset of patients for targeted molecular therapies.

Background: Angiogenesis plays a pivotal role in neoplastic growth and metastasis formation. Vascular endothelial growth factor A (VEGFA) is a major player in physiological and tumour-induced angiogenesis and numerous human tumours have been show to overexpress VEGFA. Moreover increased VEGFA gene expression has been found frequently to correlate with tumour progression, recurrences and survival. Interestingly, several studies have demonstrated that gene amplification may result in protein overexpression and that amplification of the therapeutics' target gene can serve as an excellent predictive marker (i.e. HER2 and trastuzumab). However the impact of VEGFA gene amplification has been only recently assessed for some cancer types such as osteosarcoma, colorectal, breast and liver cancer. Aims: This study aimed to assess VEGFA gene amplification status using fluorescent in situ hybridization (FISH) in a large cohort of different tumour entities. Thus, we investigated the incidence of VEGFA amplification using a multi-tumour tissue microarray (TMA) containing 2,837 evaluable specimens from 80 different tumour entities and 31 normal tissue types. Moreover, we validated FISH analysis as reference method to evaluate VEGFA gene status by comparing it to comparative genomic hybridization (CGH). Results: We observed that VEGFA locus amplification and/or polysomy represented a small but regularly detected population in several tumour entities while was not present in normal tissues. VEGFA gene alterations were predominantly observed in hepatocarcinomas, adenocarcinomas of the pancreas and intestine, large cell carcinoma of the lung and in endometrium serous carcinoma. Furthermore our data demonstrated that VEGFA detection by FISH provided highly comparable results to those generated by CGH. Conclusion: Albeit with low percentage, VEGFA amplification is commonly observed across several tumour entities. Furthermore, our results demonstrated that FISH test could be used as a reliable diagnostic tool to evaluate VEGFA gene status in human specimens.

// Michael T. Barrett 1 , Karen S. Anderson 2 , Elizabeth Lenkiewicz 1 , Mariacarla Andreozzi 1 , Heather E. Cunliffe 3 , Christine L. Klassen 4 , Amylou C. Dueck 5 , Ann E. McCullough 6 , Srikanth K. Reddy 7 , Ramesh K. Ramanathan 8 , Donald W. Northfelt 8 , Barbara A. Pockaj 4 1 Department of Research, Mayo Clinic in Arizona, Scottsdale, Arizona, United States of America 2 Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America 3 Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand 4 Division of General Surgery, Section of Surgical Oncology, Mayo Clinic in Arizona, Phoenix, Arizona, United States of America 5 Section of Biostatistics, Mayo Clinic in Arizona, Scottsdale, Arizona, United States of America 6 Department of Pathology and Laboratory Medicine, Mayo Clinic in Arizona, Scottsdale, Arizona, United States of America 7 Vanderbilt University, Nashville, Tennessee, United States of America 8 Division of Hematology-Oncology, Mayo Clinic in Arizona, Scottsdale, Arizona, United States of America Correspondence to: Michael T. Barrett, e-mail: Barrett.michael@mayo.edu Keywords: 9p24.1 amplicon, flow sorting, triple negative breast cancer, JAK2, PD-L1 Received: May 05, 2015 Accepted: June 22, 2015 Published: July 03, 2015 ABSTRACT We used DNA content flow cytometry followed by oligonucleotide array based comparative genomic hybridization to survey the genomes of 326 tumors, including 41 untreated surgically resected triple negative breast cancers (TNBC). A high level (log 2 ratio ≥1) 9p24 amplicon was found in TNBC (12/41), glioblastomas (2/44), and colon carcinomas (2/68). The shortest region of overlap for the amplicon targets 9p24.1 and includes the loci for PD-L1 , PD-L2 , and JAK2 (PDJ amplicon). In contrast this amplicon was absent in ER+ (0/8) and HER2+ (0/15) breast tumors, and in pancreatic ductal adenocarcinomas (0/150). The PDJ amplicon in TNBCs was correlated with clinical outcomes in group comparisons by two-sample t -tests for continuous variables and chi-squared tests for categorical variables. TNBC patients with the PDJ amplicon had a worse outcome with worse disease-free and overall survival. Quantitative RT-PCR confirmed that the PDJ amplicon in TNBC is associated with elevated expression of JAK2 and of the PD-1 ligands. These initial findings demonstrate that the PDJ amplicon is enriched in TNBC, targets signaling pathways that activate the PD-1 mediated immune checkpoint, and identifies patients with a poor prognosis.

Background: Triple negative breast cancer (TNBC) is a heterogeneous disease. Amplification of chromosome 9p24.1 encoding JAK2 and PD-L1 has been reported in up to 25% of TNBC and is associated with poor clinical outcome. In lymphoma, JAK2 is a transcriptional activator of both PD-1 ligands, and chromosome 9p copy number gain has been associated with therapeutic activity of nivolumab. We evaluated the interaction of JAK2 and PD-L1 expression in TNBC. Methods: 9p24.1 amplification in 4 TNBC cell lines (MDA-MB-231, MDA-MB-436, HCC1937, and HCC70) was measured using array comparative genomic hybridization (aCGH). Amplification was defined as aCGH log2ratio>2.0. Cell surface expression of PD-L1 was detected by flow cytometry and compared with the median fluorescence intensity (MFI) of isotype control Ig. To selectively inhibit JAK2, lentiviral vectors encoding two different shRNA were generated. JAK2, pSTAT1 and pSTAT3 expression were measured by immunoblot. The effects of the anti-JAK1/2 inhibitor ruxolitinib and interferon-gamma (IFN-γ) induction of PD-L1 was measured. Results: 9p24.1 copy number loss was measured in MDA-MB-231 (log2ratio =-1), neutral in HCC1937 ((log2ratio =0), gained in MDA-MB-436 ((log2ratio =+1) and amplified in HCC70 ((log2ratio =+2). No correlation was observed between PD-L1 expression and the 9p24.1 amplification, with the MFI ratio range from 5 to 16.5, mean 8.3 by flow cytometry. TNBC cell lines had higher baseline expression of PD-L1 compared to the ER+ cell lines T47D and MCF-7 (ratio, 0 p=0.1). Low dose IFN-γ (1.0-10.0 ng/ml) rapidly induced expression of PD-L1 in MDA-MB-231 (1.5 fold increase) and HCC70 (3.3 fold increase) with significant activation of the JAK2/STAT1 pathway. The induction of pSTAT1 and PD-L1 expression by IFN-γ was blocked with low dose (1mM) JAK1/2 inhibitor ruxolitinib. Knockdown of JAK2 with shRNA (>80%) did not impact PD-L1 baseline expression in MDA-MB-231 and HCC70 but abrogated IFN-γ –mediated induction of PD-L1 and the phosphorylation of STAT1. Conclusion: These data suggest that TNBC cell lines have baseline PD-L1 expression, but the cells with 9p24.1 amplification are highly sensitive to PD-L1 induction with IFN-γ which can be abrogated with inhibition with a JAK1/2 inhibitor or shRNA. Synergistic inhibition of PD1/PD-L1 and JAK2 may have therapeutic efficacy in the subset of TNBC with 9p24.1 amplification, and the dynamic effects of tumor PD-L1 expression in response to local inflammation should be considered in the evaluation of PD-1/PD-L1 checkpoint blockade. Citation Format: Chen M, Pockaj B, Andreozzi M, Barrett MT, Ocal IT, McCullough AE, Krishna S, Anderson KS. JAK2 and PD-L1 amplification enhance the dynamic expression of PD-L1 in triple negative breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-04-18.

Background Activation of the JAK/STAT pathway is common in triple-negative breast cancer (TNBC) and affects the expression of genes controlling immune signaling. A subset of TNBC cases will have somatic amplification of chromosome 9p24.1, encoding PD-L1, PD-L2, and JAK2, which has been associated with decreased survival. Materials and Methods Eleven TNBC cell lines were evaluated using array comparative genomic hybridization. A copy number gain was defined as an array comparative genomic hybridization log2 ratio of ≥ 1. Cell surface expression of programmed cell death ligand 1 (PD-L1) was detected using flow cytometry and compared with the median fluorescence intensity of isotype control immunoglobulin. To selectively inhibit JAK2, lentiviral vectors encoding 2 different short hairpin RNA (shRNA) were generated. JAK2, STAT1, STAT3, phosphorylated (p) STAT1, and pSTAT3 expression were measured by immunoblot. Statistical significance was defined as P Results The cell line HCC70 had 9p24.1 copy number amplification that was associated with both increased JAK2 and pSTAT3; however, knockdown of JAK2 inhibited cell growth independently of 9p24.1 copy number status. In TNBC cell lines with 9p24.1 gain or amplification, PD-L1 expression rapidly and strikingly increased 5- to 38-fold with interferon-γ (P Conclusion These data suggest that the JAK2/STAT1 pathway in TNBC might regulate the dynamic expression of PD-L1 that is induced in the setting of an inflammatory response. Inhibition of JAK2 might provide a synergistic therapy when combined with other immunotherapies in the subset of TNBC with 9p24.1 amplification.

VEGFA is an angiogenic factor secreted by tumors, in particular those with VEGFA amplification, as well as by macrophages and lymphocytes in the tumor microenvironment. Here we sought to define the presence of M1/M2 macrophages, PD-1-positive lymphocytes and PD-L1 tumoral and stromal expression in colorectal cancers harboring VEGFA amplification or chromosome 6 polysomy. 38 CRCs of which 13 harbored VEGFA amplification, 6 with Chr6 polysomy and 19 with neutral VEGFA copy number were assessed by immunohistochemistry for CD68 (marker for M1/M2 macrophages), CD163 (M2 macrophages), programmed death 1(PD-1)- tumor infiltrating and stromal lymphocytes as well as tumoral and stromal PD-1 ligand (PD-L1) expression. CRCs with VEGFA amplification or Chr6 polysomy were associated with decreased M1/M2 macrophages, reduced PD-1-expressing lymphocyte infiltration, as well as reduced stromal expression of PD-L1 at the tumor front. Compared to intermediate-grade CRCs, high-grade CRCs were associated with increased M1/M2 macrophages and increased tumoral expression of PD-L1. Our results suggest that VEGFA amplification or Chr6 polysomy is associated with an altered tumor immune microenvironment.

BACKGROUND: HMGA1 is a non-histone nuclear protein that regulates cellular proliferation, invasion and apoptosis and is overexpressed in many carcinomas. In this study we sought to explore the expression of HMGA1 in HCCs and cirrhotic tissues, and its effect in in vitro models. METHODS: We evaluated HMGA1 expression using gene expression microarrays (59 HCCs, of which 37 were matched with their corresponding cirrhotic tissue and 5 normal liver donors) and tissue microarray (192 HCCs, 108 cirrhotic tissues and 79 normal liver samples). HMGA1 expression was correlated with clinicopathologic features and patient outcome. Four liver cancer cell lines with stable induced or knockdown expression of HMGA1 were characterized using in vitro assays, including proliferation, migration and anchorage-independent growth. RESULTS: HMGA1 expression increased monotonically from normal liver tissues to cirrhotic tissue to HCC (P

We recently established the rationale that NRBP1 (nuclear receptor binding protein 1) has a potential growth-promoting role in cell biology. NRBP1 interacts directly with TSC-22, a potential tumor suppressor gene that is differently expressed in prostate cancer. Consequently, we analyzed the role of NRBP1 expression in prostate cancer cell lines and its expression on prostate cancer tissue microarrays (TMA).

Introduction: Previously, we detected amplification of chromosome 9p24.1 encoding PDL1, PDL2, and JAK2 (the PDJ amplicon) in up to 25% of triple negative breast cancers (TNBC) using oligonucleotide CGH arrays (aCGH). Amplification was associated with poor outcome and activation of the JAK/STAT pathway. Here, we have developed a novel fluorescence in situ hybridization (FISH) for detection of the JAK2/PDL1 amplification. Methods: We selected five 9p24.1-amplified and five non-amplified paraffin embedded TNBC tumor samples, defined by aCGH log2ratio>2.0 as amplified for FISH validation. 5' JAK2 DNA labeled with SpectrumGreen dUTP, 3' JAK2 DNA labeled in SpectrumOrange dUTP and a commercially available chromosome 9 centromeric probe (Spectrum Aqua) were combined as one probe set. The break-apart (BAP) probe set was applied to individual slides, hybridized, and washed, 50 events/sample were counted. We defined 9p24.1 amplification by FISH as the ratio of average JAK2 score/ average centromere 9 (CEN 9) score >1.1. Nonparametric student's t-test was used for statistical analysis. Results: In the amplified subgroup (n=5), JAK2 amplification was detected by FISH with the range from 1.89 to 21.0 (mean, 6.76). To adjust for aneuploidy, the ratio of JAK2 to CEN 9 was measured with the range from 1.02 to 9.21 (mean ratio, 2.9). The sample with highest level of amplification (aCGH log2ratio =4) detected by aCGH also scored highest by FISH (FISH ratio=9.21). One case with JAK2 amplification (aCGH log2ratio =3) was not detected by FISH (ratio, 1.02), but had low tumor cell content. In the non-amplification subgroup (n=5), JAK2 amplification was detected by FISH with the range from 0.98 to 3.54 (mean, 1.8), the ratio of JAK2 to CEN 9 was measured with the range from 0.48 to1.05 (mean, 0.73). Of note, two tumors with copy number loss by aCGH were confirmed by FISH (ratio 0.48, 0.56). In total, the 9p24.1 amplification was detected in 4 out 5 (80%) amplified samples defined by aCGH and 5 out 5 not amplified. A significant difference in JAK2: CEN 9 ratio (p=0.03) was observed between the amplified and non-amplified subgroups but not in JAK2 absolute scores (p=0.095). Conclusion: In this study, we have developed a novel FISH assay for detection of the 9p24.1 amplification in TNBC, encoding JAK2, PD-L1, and PD-L2. The FISH assay correlates with detection of the amplification by aCGH, but is less sensitive, in particular in tissue with lower tumor cell content. We predict that 9p24.1 amplification will be a clinically relevant biomarker in TNBC. Citation Format: Chen M, Andreozzi M, Pockaj B, Barrett MT, Ocal IT, McCullough AE, Anderson KS. A novel fluorescence in situ hybridization assay to detect 9p24.1 amplification in triple negative breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-07-17.

Death rates from hepatocellular carcinoma (HCC) are steadily increasing, yet therapeutic options for advanced HCC are limited. We identify a subset of mouse and human HCCs harboring VEGFA genomic amplification, displaying distinct biologic characteristics. Unlike common tumor amplifications, this one seems to work via heterotypic paracrine interactions; stromal VEGF receptors (VEGFR), responding to tumor VEGF-A, produce hepatocyte growth factor (HGF) that reciprocally affects tumor cells. VEGF-A inhibition results in HGF downregulation and reduced proliferation, specifically in amplicon-positive mouse HCCs. Sorafenib—the first-line drug in advanced HCC—targets multiple kinases, including VEGFRs, but has only an overall mild beneficial effect. We found that VEGFA amplification specifies mouse and human HCCs that are distinctly sensitive to sorafenib. FISH analysis of a retrospective patient cohort showed markedly improved survival of sorafenib-treated patients with VEGFA-amplified HCCs, suggesting that VEGFA amplification is a potential biomarker for HCC response to VEGF-A–blocking drugs. Significance: Using a mouse model of inflammation-driven cancer, we identified a subclass of HCC carrying VEGFA amplification, which is particularly sensitive to VEGF-A inhibition. We found that a similar amplification in human HCC identifies patients who favorably responded to sorafenib—the first-line treatment of advanced HCC—which has an overall moderate therapeutic efficacy. Cancer Discov; 4(6); 730–43. ©2014 AACR. See related commentary by Luo and Feng, p. 640 This article is highlighted in the In This Issue feature, p. 621

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide. The lack of effective therapeutic options for advanced stage HCCs combined with an increasing incidence rate calls for the identification of early stage HCC molecular markers. SH2 Domain Containing 4A (SH2D4A) gene maps to human chromosome 8p21.3 and encodes for SH(2)A. The chromosomal region containing SH2D4A is frequently lost in colorectal, lung and HCC cancers. Our study aimed to investigate SH2D4A involvement in HCC pathogenesis combining mRNA expression, protein and clinical data. Transcriptome analysis performed on 37 HCC needle biopsies (matched with their corresponding non-neoplastic parenchyma) and five normal liver donor samples revealed that SH2D4A is downregulated in HCC. Results were confirmed by quantitative real-time-polymerase chain reaction (qRT-PCR), 25 out of 37 (67.6%) fresh frozen samples showed SH2D4A downregulation (p = 0.026). Furthermore, combining qRT-PCR and immunohistochemistry data we demonstrated a direct correlation between SH2D4A mRNA and SH(2)A protein levels. The analysis of a tissue microarray (TMA) containing 336 specimens confirmed that SH(2)A is frequently reduced in HCC (56.8%) as well as in cirrhotic nodules (50.5%) compared to normal liver samples (31.1%). To conclude, our study revealed that SH2D4A is frequently downregulated in HCC samples thus corroborating its putative role as a tumour suppressor gene. In addition, we provide new evidence for SH2D4A involvement in HCC pathogenesis demonstrating for the first time its deregulation in cirrhotic nodules.

Background A subset of triple negative breast cancers (TNBC) has somatic amplification of chromosome 9p24.1, encoding PD-L1, PD-L2, and JAK2 (the "PDJ" amplicon). The JAK/STAT pathway promotes malignant transformation and proliferation, and the JAK1/JAK2 inhibitor ruxolitinib is being evaluated in early phase clinical trials in breast cancer. This study was designed to measure the frequency of PDJ copy number gain in existing TNBC cell lines, and determine the impact of targeted JAK2 inhibition on cellular proliferation. Methods: Copy number alterations were measured in nine TNBC cell lines (MDA-MB-453, MDA-MB-436, BT549, MDA-MB231, MFM-223, MDA-MB-468, H5578T, MDA-MB-157, HCC1937) by array comparative genomic hybridization (aCGH). JAK2 and pSTAT3 expression was measured by immunoblot in four of the TNBC lines (HCC1937, MDA-MB-468, MDA-MB-231, MDA-MB-436) and compared with MCF10A, SK-BR3, and T47D. To selectively inhibit JAK2, lentiviral vectors encoding five different shRNA targeting JAK2 were generated. Ruxolitinib treatment was performed at 25 uM for 48 hrs and 72 hrs. Cell proliferation was measured by CellTiter-Glo. Results: All TNBC cell lines had an elevated level of baseline protein expression of JAK2 and pSTAT3 compared to SK-BR3, T47D, and MCF10A. Of the nine TNBC cell lines, only MDA-MB-436 and BT549 had copy number gain of 9p24.1 (log2ratio Conclusion These results demonstrate that existing TNBC cell lines have varying copy number alterations of chromosome 9p24.1 encoding JAK2, and targeted JAK2 inhibition in TNBC inhibits cell proliferation. Citation Format: Chen M, Andreozzi M, Gonzalez-Malerva L, Eaton S, Pockaj B, Barrett MT, Anderson KS. JAK2 copy number and targeted JAK2 inhibition of TNBC cell lines. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-04-19.

Introduction: In a pilot study, we recently described amplification of chromosome 9p24 encoding PD-L1, PD-L2, and JAK2 (the PDJ amplicon) in 29% of early stage triple negative breast cancers (TNBC). Amplification was associated with poor DFS and OS. The impact of this amplicon on immune function is not known. Methods: Fresh frozen tumor samples from 36 subjects with newly-diagnosed TNBC (stages I-III) were evaluated for copy number aberrations using DNA-based flow cytometry to enrich nuclei based on ploidy status (tetraploidy or aneuploidy), followed by oligonucleotide CGH arrays. Targeted immune expression profiling was performed using the Nanostring PanCancer Immune Profiling Panel (n=770 genes). Results: 23 samples had measurable abnormal ploidy (evidence of sufficient tumor content) for CGH analysis; the remaining samples were omitted from analysis. High level (log2ratio >1) amplification was detected in 6/23 (26.1%) of TNBCs, and low-level copy number gain (CN log2ratio >0 and-1 and Conclusion: Amplification of chromosome 9p24.1 involving PD-L1, PD-L2, and JAK2 is present in a significant proportion of TNBCs. This amplicon is associated with altered gene expression of the tumor microenvironment. Citation Format: Anderson KS, Andreozzi M, Pockaj BA, Hopper M, McCullough AE, Barrett MT. Amplification of chromosome 9p24 targeting PD-L1 and JAK2 correlates with altered tumor microenvironment expression profiles in triple negative breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-04-02.

Background: Breast tumors exhibit intratumor heterogeneity resulting in targeted therapy resistance and other challenges in disease management. To address the sources of heterogeneity, we performed a unique, in-depth analysis of clonal architecture in primary chemoradiation-naïve breast cancers. We combined DNA content-based flow cytometry and ploidy analysis with aCGH and whole exome next-generation sequencing (NGS) in multiple biopsies from the tumors and involved lymph nodes (LNs). Material and methods: We sorted nuclei from distinct populations of diploid, tetraploid, and aneuploid cells in surgical tumor samples from three chemoradiation-naïve patients. Each sorted tumor cell population was interrogated with aCGH and whole exome NGS. In Patient #1, we sorted and interrogated the genomes of tumor populations from 12 fresh frozen sections morphologically mapped from within a HER2+, ER+, PR- primary invasive ductal carcinoma (IDC) of histological grade 3 with LN involvement and 2-3 sections from 2 out of 5 LNs. In Patient #2, 11 morphologically mapped fresh frozen sections were analyzed from a grade 2, ER+, PR+, HER2+, BRCA2 mutant LN- IDC. In parallel, matching samples were processed for IHC assays. In Patient #3 biopsies from a grade 2 ER+, PR+ primary tumor were profiled. Results: The 18 primary and LN biopsies from Patient #1 fell into 6 distinct ploidy groups albeit with aberrant but homogenous aCGH profiles, characterized by SARC amplification and homozygous deletions in ROBO1 and ROBO2. In contrast a dominant ploidy was identified throughout 10 biopsies in Patient #2 but with heterogeneous aCGH profiles. Patient #3 had a clonal homozygous deletion in Numb in each of 4 tumor biopsies. Mutation profiles obtained through exome sequencing further confirmed that ploidy was the main driver in Patient #1 whereas copy number aberrations played the key role in Patient #2 with the BRCA2 mutation (R3129X). A dendrogram based on exome variant calls of the aneuploid populations in Patient #1 strongly correlated with ploidy group and further revealed the specific clonal population characterized by a 5N ploidy and homozygous mutations in TP53 and PIK3CA as the progenitor to the ploidies present in the distant LNs. Strikingly, patients #1 and #2 were HER2 wild type across their clonal populations, contradicting IHC staining in a single core biopsy. Conclusions:Rather than inferring the presence of distinct tumor cell populations, our flow-sorting based approach of first identifying clonal populations and then interrogating their genomes, provides an objective method of exploring the sources and clinical significance of tumor heterogeneity. Our approach of clonal analysis has broad implications in the study of tumor heterogeneity and the identification of drivers in breast and other solid tumors that can advance more effective treatment and clinical management of patients with this disease. Citation Format: MARIACARLA ANDREOZZI, Princy Francis, Elizabeth Lenkiewicz, Mia Champion, Brady Laughlin, Karen Anderson, Heather Cunliffe, Ann E. McCullough, Michael T. Barrett, Barbara Pockaj. Deep clonal profiling identifies distinct mechanisms of heterogeneity and evolution in breast cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-175. doi:10.1158/1538-7445.AM2015-LB-175

Background and aim: Mounting evidence suggest that hepatocellular carcinoma (HCC) contains a subset of cells possessing some functional properties similar to normal tissue stem cells, usually referred as cancer stem cells (CSCs). THY1 (aka CD90) is involved in tumor-genesis and is commonly acknowledged as a maker of CSC in HCC. HMGA1, an HMG (high mobility group) chromatin-remodelling protein, has been recently highlighted as a key player in stem cell biology. HMGA1 overexpression induces malignant transformation in vitro and is deregulated in many cancer entities. This study aims to address the interrelated role of HMGA1 and THY1 in HCC. Methods: Using a global transcriptomic profiling (Affymetrix), validated by RT-qPCR, we analysed HMGA1 and THY1 expression levels in a cohort of HCC needle biopsy matched with corresponding non-neoplastic liver (total n=118) and normal liver (n=5). Using tissue microarray (TMA) technology, we evaluated by immunohistochemical staining HMGA1 and THY1 protein levels in a large collective of liver specimens (n=434, of which n=216 were HCCs). Results: We observed that both HMGA1 and THY1 expression is significantly up regulated in a subset of HCC specimens, correlating with metastatic disease and histological grading. Additionally, we demonstrate that high HMGA1 protein levels along with THY1 positivity in HCC samples results in unfavorable patients' outcome and disease progression. Conclusion: With this work we provide new evidence for HMGA1 and THY1 involvement in HCC progression and disease outcome and set the basis for further studies aiming to address their role in CSC biology of HCC. Citation Format: Mariacarla Andreozzi, Luca Quagliata, David Benz, Francesca Trapani, Serenella Eppenberger-Castori, Christian Ruiz, Pierlorenzo Pallante, Markus Heim, Luigi Tornillo, Alfredo Fusco, Salvatore Piscuoglio, Luigi Maria Terracciano. Enhanced expression of HMGA1 and THY1 in human hepatocellular carcinoma correlates with poor prognosis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1386. doi:10.1158/1538-7445.AM2014-1386

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide. The lack of effective therapeutic options combined with an increasing incidence rate in the past 20 years calls for the identification of early stage HCC molecular markers. SH2D4A maps to human chromosome 8p21.3 and encodes for SH(2)A. The chromosomal region containing SH2D4A has been shown to be frequently lost in colorectal, lung and HCC cancers. Using a combination of gene expression, protein level and clinical data, our study aimed to investigate the SH2D4A involvement in HCC pathogenesis. Transcriptome analysis (Affymetrix) performed on 37 HCC samples (matched with their corresponding non-neoplastic liver parenchyma) and 5 normal liver donors revealed that SH2D4A is downregulated in HCC. These results were validated by qPCR in fresh frozen tissues [25 out of 37 samples (67.6%) showed SH2D4A downregulation; p Citation Format: Mariacarla Andreozzi, Luca Quagliata, Michal Kovac, Luigi Tornillo, Zuzanna Makowska, Marcus Heim, Karl Heinimann, Salvatore Piscuoglio, Luigi Maria Terracciano. SH2D4A is frequently downregulated in hepatocellular carcinoma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4685. doi:10.1158/1538-7445.AM2013-4685 Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.

Background The VEGFA protein plays an important role in the induction of angiogenesis during tumor initiation and progression. The aims of the study were to investigate the presence of VEGFA gene amplification by FISH analysis on a human multi-tumor tissue microarray (MTMA) and to validate these findings on an independent human multi-tumor tissue in mouse implanted microarray (MTMA) by aCGH, SNP6 microarrays, FISH analysis and real-time PCR. Materials and Methods The VEGFA gene status was evaluated on a human MTMA (n=2,957 tissue samples) including 132 tumor entities and 31 normal tissue types. Furthermore, we reconfirmed the presence of VEGFA gene amplification as detected by FISH analysis on a second independent MTMA including 195 different tissue samples from nude mice xenograft models of 24 different human tumor types using three additional genomic techniques: array-CGH, SNP6 microarrays and real-time PCR. Results VEGFA gene amplification was detected across different tumor types. The following incidences were observed: 5.3% in colorectal carcinoma, 3.2% in endometrial carcinoma, 2.8% in gallbladder adenocarcinoma, 4.2 % in renal carcinoma, 1.5% in hepatocellular carcinoma, 4.5% in pancreas carcinoma and 4.8% in stomach carcinoma samples. Additionally, some tumors were characterized by a high polysomy. In the second independent cohort MTMA VEGFA gene amplification was detected by FISH analysis in four samples, including one non-small cell lung cancer, one sarcoma, one gastric and and breast cancer, previously classified as amplified by aCGH (100%) and SNP6 microarrays. The latter technique also revealed one “supplementary amplified sample”. All results correlated with real-time PCR (p Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5295. doi:1538-7445.AM2012-5295

Background: Around 30% of patients with early-stage non-small cell lung cancer (NSCLC) relapse after surgery. Therefore, new prognostic and predictive molecular markers are needed to identify patients who could benefit from adjuvant treatment. SOX2 (sex determining region Y-box 2) at the gene locus 3q26.33 is regarded as an oncogene involved in carcinogenesis of squamous cell lung carcinoma. Nevertheless, comprehensive data on SOX2 gene status and expression as well as its prognostic relevance in early-stage NSCLC are not yet available. The aim of the present study was to investigate the prevalence and the prognostic significance of SOX2 gene status and expression in a large series of stage I NSCLC patients. Methods: A tissue micro array with 568 paraffin-embedded stage I NSCLC with comprehensive histopathological and clinical data, including follow-up on overall and tumor-specific survival was analyzed. SOX2 gene status was determined by fluorescent in situ hybridization (FISH) using direct-labeled BAC clones (SOX2: RP11-938O9; reference probe (RP): RP11-286G5). SOX2 gene status was recorded as follows: Amplification (ratio SOX2/RP ≥2.2), polysomy (more than 4 signals in the CEP or the gene probe) and normal (ratio: 0.8-1.8). Semi-quantitative expression of SOX2 protein was determined by immunohistochemistry (IHC). Any nuclear reaction of tumor cells was regarded as a positive result. FISH and IHC data were correlated with clinicopathological features and overall survival. Results: An increased SOX2 gene number (amplification or polysomy) was observed in 4% of NSCLC (17/429). 94% of NSCLC (16/17) with an increased SOX2 gene number were observed in squamous- and large cell carcinomas (non-adenocarcionomas). Using logistic regression analysis an increased SOX2 gene number was significantly (p50years; p=0.001) and male (p>0.001) patients. Elderly male patients with non-adenocarcionoma histology and a smoking history expressing SOX2 had a tendency toward more recurrence (p=0.06). Conclusions: An increased SOX2 gene number is rare in stage I NSCLC and it is mostly detected in squamous and large cell carcinomas. SOX2 protein expression stratifies a subgroup of NSCLC from elderly patients with a smoking history and non-adenocarcinoma histology. SOX2 two could become a potential therapeutic target molecule in a subgroup of patients with early stage NSCLC. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3815. doi:10.1158/1538-7445.AM2011-3815