96 Background: In the last decade there has been an increase in the incidence of contralateral prophylactic mastectomy (CPM) for unilateral breast cancer. Although many factors have been proposed to explain this trend, the impact of breast reconstruction on the decision to undergo CPM has not been extensively studied. Methods: A retrospective review of breast cancer patients from Surveillance, Epidemiology and End Results (SEER) registry data (2004-2008) was conducted. Characteristics of patients undergoing CPM were evaluated. Results: 71,176 patients with a diagnosis of stage I-III infiltrating ductal or lobular breast cancer underwent mastectomy for their primary lesion. Among these, 10,558 patients (15%) underwent a CPM. A significantly higher proportion of women undergoing CPM had reconstruction performed (44%) than those patients not undergoing CPM (13%), p<0.001. On multivariate analysis (Table), significant variables predicting CPM included age <50 years (OR 10.12), breast reconstruction (OR 3.58), and lobular histology (OR 1.41), all p<0.001. Of the 12,466 patients (18%) who underwent reconstruction, 4,636 (37%) had implant reconstruction, 4,498 (36%) had tissue reconstruction, and 1,122 (9%) had combined tissue/implant reconstruction (no data for 18%). On multivariate analysis, predictors of reconstruction included age <50 years (OR 20.5; CI 18.5-22.7), year of surgery (2008 vs. 2004; OR 1.60; CI 1.49-1.71), low tumor grade (OR 1.19; CI 1.13-1.25) and ER+ status (OR 1.16; 95% CI 1.10-1.23). The use of radiation therapy was associated with a lower likelihood of pursuing reconstruction (OR 0.61; CI 0.58-0.65). Conclusions: Apart from age, the factor most strongly associated with CPM is the decision to have reconstructive surgery performed. This suggests that CPM may not be purely associated with risk-reduction but also with treatment factors such as cosmesis. [Table: see text]
Results of NCCTG N0275 (Alliance) – a phase II trial evaluating resection followed by adjuvant radiation therapy for patients with desmoplastic melanoma
AbstractTo examine, in a prospective fashion, the utilization and efficacy of adjuvant radiation therapy (RT) in patients with resected desmoplastic melanoma (DM). Adult patients with resected, margin‐negative, and nonmetastatic DM were eligible for this single‐arm prospective phase II study. Patients were to receive postoperative RT, 30 Gy in five fractions, to the operative bed with 2‐ to 3‐cm margins (depending on the tumor location). Nodal basin RT was not allowed. The primary study endpoint was the 2‐year local recurrence rate (LRR). Secondary endpoints included the incidence of regional and distant metastatic disease, progression‐free survival, overall survival (OS), and treatment‐related toxicity. Twenty patients with a single de novo DM lesion meeting trial eligibility criteria were enrolled and treated. The 2‐year LRR was 10%, with two patients demonstrating a LR within 2 years of completion of protocol therapy. No regional or distant failures occurred. OS at 2 and 5 years was 95 and 77%, respectively. There were no grade 3 or higher acute or late adverse events that were related to the protocol therapy. Adjuvant RT after wide local excision (WLE) for DM is efficacious and well tolerated. It should be considered for DM patients after margin‐negative WLE. Additional study is needed to further refine low‐risk patient populations that can potentially have adjuvant RT omitted as part of the treatment plan.
Aberrant Glycosylation of Anchor-Optimized MUC1 Peptides Can Enhance Antigen Binding Affinity and Reverse Tolerance to Cytotoxic T Lymphocytes
Cancer vaccines have often failed to live up to their promise, although recent results with checkpoint inhibitors are reviving hopes that they will soon fulfill their promise. Although mutation-specific vaccines are under development, there is still high interest in an off-the-shelf vaccine to a ubiquitous antigen, such as MUC1, which is aberrantly expressed on most solid and many hematological tumors, including more than 90% of breast carcinomas. Clinical trials for MUC1 have shown variable success, likely because of immunological tolerance to a self-antigen and to poor immunogenicity of tandem repeat peptides. We hypothesized that MUC1 peptides could be optimized, relying on heteroclitic optimizations of potential anchor amino acids with and without tumor-specific glycosylation of the peptides. We have identified novel MUC1 class I peptides that bind to HLA-A*0201 molecules with significantly higher affinity and function than the native MUC1 peptides. These peptides elicited CTLs from normal donors, as well as breast cancer patients, which were highly effective in killing MUC1-expressing MCF-7 breast cancer cells. Each peptide elicited lytic responses in greater than 6/8 of normal individuals and 3/3 breast cancer patients. The CTLs generated against the glycosylated-anchor modified peptides cross reacted with the native MUC1 peptide, STAPPVHNV, suggesting these analog peptides may offer substantial improvement in the design of epitope-based vaccines.
Abstract P6-03-13: The genomic landscape of PD-L1, PD-L2, Jak2 (PDJ) amplified triple negative breast carcinoma
Abstract Introduction: Triple negative breast carcinoma (TNBC) is a subtype of breast cancer with a paucity of therapeutic targets and a poor prognostic phenotype. In a retrospective cohort, we sought to determine the prevalence of the amplicon targeting the 9p24.1 locus, resulting in over-expression of PD-L1, PD-L2, and JAK2 (PDJ), and potentially actionable therapeutic targets. We then probed the genomic landscape of these PDJ positive tumors and identified co-occurring copy number aberrations, including focal amplifications and homozygous deletions. The presence of the PDJ amplicon and selected co-occurring aberrations provide a unique description of a clinically relevant subtype of TNBC. Methods: We evaluated fresh frozen and formalin-fixed paraffin embedded tumor samples from 64 patients with triple negative breast cancer whom underwent definitive surgical resection. Clinical annotation was available in 60 of the samples. Tumor populations (diploid, tetraploid, and aneuploidy) were sorted from each biopsy using DNA content flow cytometry. Each sorted sample was interrogated with oligonucleotide array comparative genomic hybridization (aCGH). All microarray slides were scanned using an Agilent 2565C DNA scanner and the images were analyzed with Agilent Feature Extraction version 10.7. The aCGH data was assessed with a series of QC metrics then analyzed using an aberration detection algorithm. Results: We detected a high level (log2ratio greater than or equal to 2) amplicon targeting 9p24.1 in 18 of 64 patients (28%) genomic profiles with triple negative breast carcinoma. In the PDJ positive population, we detected 8 of 18 patients (44%) with co-amplification targeting myc at 8q24, 3 of 18 patients (17%) with co-amplifications targeting EGFR at 7p11, 3 of 18 patients (17%) with co-amplifications targeting PIK3CA. These co-occurring genomic events in PDJ positive tumors may provide clinically actionable targets. Other selected amplifications detected included NOTCH3, KRAS, RUNX1, TUBAL3, FGFR2, AKT1, AKT2, YPEL2, PBXL7, KIT. We detected PTEN homozygous deletion in 2 of 18 patients (11%) PDJ positive tumors. Other homozygous deletions identified in the genomic landscape included FAT1, SOX3, Park2, TNFAIP3, GPC3, RB1, and CREBBP. Conclusions: In our retrospective analysis, the amplification of chromosome 9p24.1 involving PD-L1, PD-L2, and JAK2 is present in approximately 28% of triple negative breast cancer patients. The genomic landscape of these PDJ positive TNBCs include recurring high-level focal amplifications and targeted homozygous deletions of clinically relevant genes. The clinical implications of these data are under current investigation using model systems and are in early phase clinical trials. The efficacy of immune checkpoint inhibitors including nivolumab, pembrolizumab, and JAK2 inhibitors including ruxolitinib, in PDJ positive triple negative breast carcinoma is intriguing and remains to be elucidated. Citation Format: Gawryletz CD, Anderson KS, Cunliffe HE, Northfelt DW, McCullough AE, Lenkiewicz E, Malasi S, Pockaj BA, Barrett MT. The genomic landscape of PD-L1, PD-L2, Jak2 (PDJ) amplified triple negative breast carcinoma. [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 P6-03-13.
Abstract P5-04-19: JAK2 copy number and targeted JAK2 inhibition of TNBC cell lines
Abstract 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<1). Four independent shRNA efficiently silenced over 90% of JAK2 expression in MDA-MB-231. The inhibition of JAK2 in MDA-MB-231 was associated with a decrease in both JAK2 and pSTAT3 protein expression and reduction in cell proliferation compared to control shRNA after 96 hrs (p<0.0001). Inhibition of proliferation was also observed for both MDA-MB-231 and MDA-MB-436 after ruxolitinib treatment. 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.
Abstract P4-09-19: Comprehensive multiplatform molecular profiling identifies potentially targetable biomarkers in malignant phyllodes tumors of the breast
Abstract Introduction: Malignant phyllodes tumors are rare breast malignancies (0.1% of all breast tumors) with limited effective treatment options for recurrent and metastatic disease. Recent trials indicated a potential for anti-angiogenic therapy in soft tissue sarcomas, which led us to investigate these pathways. Materials and Methods: Thirty-five malignant phyllodes tumors (including two cases with matched primary and metastatic tumors) were profiled using gene sequencing (Next-generation and Sanger), gene copy number analysis (in-situ hybridization), whole genome RNA expression, and protein expression (immunohistochemical assay). Results: RNA microarray assay showed consistent over-expression of genes involved in angiogenesis including VEGFA, Angiopoietin2, VCAM1, PDGFRA, PTTG1, and CYP3A5 in all cases analyzed (n=5). No mutations in KDR (VEGFR2) were detected (0/26). EGFR protein overexpression was observed in 25/26 (96%) of cases with amplification of the EGFR gene in 8 cases (33%). EGFR gene mutations were identified in 2 cases (8%) including one case with presumed pathogenic V774M mutation and one case with EGFRvIII mutation. The most common mutations included those of TP53 (50%) and PIK3CA (15%) while other mutations (BRCA1, BRCA2, RET, CDH1, MLH1, ATM) were rare affecting single phyllodes cases. Two cases with matched primary and metastatic cancers harbored the same mutations in both sites (PIK3CA/KRAS and RB1 gene mutations, respectively). Conclusions: Comprehensive multiplatform profiling approach to phyllodes tumors identifies various molecular alterations of which some are potentially actionable. Our data suggests that anti-angiogenic therapy may also be effective in patients with malignant phyllodes tumor. Evaluation of EGFR pathway discovered consistent protein over-expression but rare activating mutations, which necessitates refinement in patient selection targeting these pathways. Citation Format: Gatalica Z, Vranic S, Ghazalpour A, Xiu J, Ocal I, McGill J, Bender R, Discianno E, Sanati S, Reddy S, Pockaj B. Comprehensive multiplatform molecular profiling identifies potentially targetable biomarkers in malignant phyllodes tumors of the breast. [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 P4-09-19.
Abstract P4-04-02: Amplification of chromosome 9p24 targeting PD-L1 and JAK2 correlates with altered tumor microenvironment expression profiles in triple negative breast cancer
Abstract 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) was detected in 3/23 (13.0%). The remaining samples had no copy number change (n=9) or low level copy number loss (CN log2ratio>-1 and <0, n=5). Increased RNA expression of STAT1, STAT2, STAT3, and STAT6 was associated with PDJ amplification, as well as upregulation of the immune regulatory genes CD47 and IDO1. 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.
Multiplatform molecular profiling identifies potentially targetable biomarkers in malignant phyllodes tumors of the breast