bluuebunny/crossref_metadata_2025_split huggingface dataset:
Association of Notch signaling pathway expression in liposarcomas with outcome, and targeting with gamma-secretase inhibitors
Authors: Meng R. D. , Qin L. , Shelton C. C. , Li Y. , Maki R. G. , Brill E. R. , Singer S. , Schwartz G. K. 
Published: August 2020

10526 Background: The Notch pathway directs normal fat cell development, but its aberrant activation may promote the development of sarcomas. The expression of the Notch pathway in liposarcoma (LPS), however, is unknown. We examined Notch signaling components in LPS's and suppressed Notch activation with drug targeting in LPS cell lines. Methods: RNA was isolated from 18 normal fat and 140 LPS tissue samples from five LPS subtypes: well-differentiated (33%), de-differentiated DD (25%), myxoid (12%), round cell (6%), and pleomorphic (13%), and were hybridized to Affymetrix U133A arrays. Microarray data were normalized with the RMA method. Correlation analysis identified genes expressed between sample classes, using Empirical Bayes t-test, and genes associated with survival, using Cox regression. The Notch pathway in two LPS lines, DDLS and LS141, was suppressed with a novel gamma-secretase inhibitor (GSI) or with siRNA to Notch receptors. Viability was assessed by colony formation, apoptosis by DAPI staining, and Notch expression by immunoblotting. Results: Expression of Notch-3 and its targets, Hes-1, Hey-1, and survivin, was increased in LPS subtypes, compared to fat tissue (p<0.001). Inhibition of Notch signaling with GSI's or siRNA to Notch-1 suppressed the viability of both DD LPS lines (p<0.05), inducing a G1/S arrest followed by apoptosis. Transfection of siRNA to each Notch receptor, especially Notch-3, also suppressed the viability of DD LPS's (p<0.05). Expression of Notch-3 (p=0.027, HR=2.64), Notch-4 (p=0.026, HR=2.70), the ligand JAG-2 (p=0.049, HR=2.32), and Hey-1 (p=0.001, HR=4.25) was associated with reduced distant recurrence free survival in patients with DD LPS's. Expression of the negative Notch regulator Fbxw7 was associated with improved overall survival in patients with LPS (p=0.008, HR=-1.42). Conclusions: Elements of the Notch pathway (receptors, ligands, targets, and modifiers) are overexpressed in LPS's compared to normal fat tissue and associate with outcome. Suppression of Notch signaling decreased DD LPS cell line viability and induced apoptosis. Notch inhibition may represent a new therapeutic strategy for patients with LPS's and deserves further validation in a clinical trial. No significant financial relationships to disclose.
Molecular epidemiology of GISTs: Incidence of PDGFRA and KIT exon 9 mutations in the large French population-based study molecGIST
Authors: Emile François J. , Brahimi S. , Coindre J. , Monges G. , Scoazec J. Y. , Blay J. , Bouché O. , Aegerter P. 
Published: August 2020

10535 Background: KIT exon 11, KIT exon 9, and PDGFRA exon 18 mutations are present in 67%, 10% and 5% of gastrointestinal stromal tumors (GIST). However most of these data are based on analyses of patients with overtly metastatic tumors. The MolecGIST study was design to evaluated prospectively the histological, molecular and clinical characteristics of all GISTs diagnosed at all stages. Methods: All patients leaving in France, whose diagnosis of GIST was achieved between June 1, 2006 and May 31, 2008 were includable in the study. MolecGIST was approved by French ethical comities. Samples were collected in 11 reference centers for histology review, immunohistochemistry and detection of mutations within exon 9, 11, 13, and 17 of KIT and 12, 14, and 18 of PDGFRA. Results: In December 2008, 738 patients were referred to MolecGIST, corresponding to 5.95/million/year incidence of GIST en France (62 millions inhabitants). The median age at diagnosis 63.1 years (range [15–96]), and female/male ratio 0.98. GIST originated in the stomach in 56.3% and small bowel in 29.3% of the cases. Tumors were KIT+ in 90,4% of cases. CD34 was expressed by more than 20% of tumor cells in 83.8% of gastric GIST and 39.7% of small bowel GIST respectively (P<0.0001). The risk of metastatic relapse was moderate or high in 62.7% of the patients, according to Fletcher classification, while only in 44% according to Miettinen's. Mutation analyses were achieved in 438 cases (to be updated), and mutations of either KIT or PDGFRA were detected in 66.2% and 12.6% of the patients, and absent in 21.2%. The most frequent mutations were KIT exon 11 (59.1%), PDGFRA exon 18 (9.8%) and KIT exon 9 (4.3%). The incidence of PDGFRA exon 18 and KIT exon 9 were significantly different than the published data (P=0.0008 and P<0.0001 respectively). Among GIST of the small bowel, the mutations were KIT exon 11 (69.1%) and KIT exon 9 (13.1%). Conclusions: The PDGFRAexon18/KITexon9 mutation ratio is 4.5 times higher in our population based study than in patients included in phase III trials. The incidence of GIST with PDGFRA mutations and intestinal GIST exon KIT exon 11 mutations is underestimated in published series as compared to ours, probably because of the better prognosis. [Table: see text]
Identification of a subpopulation of metastatic breast cancer patients with very high HER2 expression levels and possible resistance to trastuzumab
Authors: Sperinde J. , Ali S. , Leitzel K. , Fuchs E. , Köstler W. J. , Paquet A. , Weidler J. , Huang W. , Bates M. , Lipton A. 
Published: August 2020

1059 Background: Many HER2-positive patients with metastatic breast cancer (MBC) fail to respond to trastuzumab. We previously reported that precise quantitation of HER2 expression (H2T) by the HERmark assay identified a sub-population of IHC 3+, FISH(+) (positive) patients with low H2T levels that responded poorly to trastuzumab (Lipton, San Antonio Breast Cancer Symposium 2008, abs #32). Here we identify a sub-population of FISH(+) patients with very high H2T levels, that experience clinical outcomes that are indistinguishable from those of FISH(-) (negative) patients with low H2T levels. Methods: The HERmark assay was used to measure H2T in formalin-fixed, paraffin-embedded (FFPE) primary breast tumor specimens from 99 women treated with trastuzumab for MBC. Specimens were also tested by central FISH. A sub-population treatment effect pattern plot (STEPP) was generated to examine the progression-free survival (PFS) rate at 12 months after treatment with trastuzumab across the distribution of H2T. Kaplan-Meier (KM) analyses were performed comparing the PFS of FISH(-), H2T low (log10H2T < 1.25) patients with those of FISH(+), H2T high (log10H2T ≥ 1.95) and FISH(+), H2T intermediate (1.25 < log10H2T < 1.95) groups. Cutoffs were identified by lowest p-value in a positional scanning analysis. Results: The PFS rate improved gradually with increasing H2T in STEPP analyses. At the highest levels of H2T, an abrupt decrease in the PFS rate was observed, consistent with a reduction in susceptibility to trastuzumab. KM analyses demonstrated that patients who were FISH(+), H2T intermediate had a significantly longer PFS than patients who were FISH(-), H2T low (median PFS 12.6 vs. 4.5 mos; HR = 0.34; p < 0.0001). Patients that were FISH(+), H2T high experienced a PFS that was no better than patients that were FISH(-), H2T low (median PFS 4.6 vs. 4.5 mos; HR = 0.87; p = 0.68). Conclusions: Precise quantitation of HER2 expression levels allows the identification of multiple sub-populations of HER2(+) patients that have different clinical outcomes on trastuzumab. MBC patients with very high levels of H2T could represent a sub-group with de novo resistance to trastuzumab who may benefit from combined therapy. [Table: see text]
Patterns of HER2/neu, hormonal receptor expression, and proliferative activity in primary and metastatic breast cancer
Authors: Giotta F. , Simone G. , Fazio V. , Longo S. , Petroni S. , Rubini V. , Liuzzi M. , Addati T. , Colucci G. 
Published: August 2020

1071 Background: The modification of biological features of metastatic sites (MS) in breast cancer patients arise some debatable questions regarding clinically usefull information and safe/efficient methods to detect them. Fine needle aspiration (FNA) of visceral MS is an available tool to characterize tumoral lesion and liquid based citology technique provides usefull cell samples for immunocytochemical and/or molecular assays. Methods: The aim of this study was to compare prognostic and predictive factors obtained from primary tumors (PT) and corresponding MS. Fluorescent in situ hybridization (FISH) was performed for HER2/Neu determination, while ER, PgR, and MIB-1 were detected by immunochemistry using specific monoclonal antibodies on monolayered cell sample and in the corresponding cytoinclusion. FNA with a 21–23 G needle was performed in 20 consecutive breast cancer patients with distant metacronous MS. Results: In 8/20 patients, both ER and PgR were absent in PT and in MS, in 7 were both present, in 4 cases only ER was detected, and only 1 case was ER negative with a low PgR. About the proliferative activity (MIB-1 index: cut off value >20%) only 3 MS presented an higher value. With regard to HER2/Neu, 4/20 cases were amplified and no discrepancies were found between cytological and cytoinclusion specimens. No substantial changes were found about kinetic activity. HER2/Neu status as assessed in PT was confirmed in MS in 10/12 cases; a lung mestastasis showed amplification while primary was not amplified and a liver lesion lost the amplification which was detected in the PT. Conclusions: Our study strongly suggest the opportunity in using FNA for detection of prognostic and predictive factors in MS. Pectasides et al. (Anticancer Res. 2006) found in patients with altered or conserved HER2/Neu in PT and in MS different response rates between the two groups and a significant poorer prognosis in patients with altered Neu. We think that liquid-based cytology applied on FNA of distant metastases could help us to understand some more in this issue. No significant financial relationships to disclose.
Randomized, phase II trial comparing continuous versus intermittent capecitabine monotherapy for metastatic breast cancer (MBC)
Authors: Martín M. , Calvo L. , Martínez N. , Ramos M. , Muñoz M. , Zamora P. , Hernando B. , Casado A. , García-Saenz J. A. , Puente J. 
Published: August 2020

1086 Background: The approved capecitabine (X) regimen in MBC is 1,250 mg/m2 bid, d1–14 q21d (Xint). However, dose modifications are often required primarily for hand-foot syndrome and diarrhea. Therefore we designed an alternative regimen aimed to reduce the severity of these side effects while maintaining the total cumulative dose and efficacy of X. Methods: The primary objective was to show non-inferiority of X 800 mg/m2 bid, d1–21 q21d (Xcont) to Xint in terms of 1-year PFS rate. Secondary endpoints included response rate (RECIST), PFS, duration of response, OS, and safety (NCI CTCAE v2.0). Assuming median PFS of 5 months and 2-sided α=0.05, 176 evaluable patients (pts) will be needed to give 80% power. Pts are ineligible if they have received >2 chemotherapy regimens for MBC or prior X, or if they have HER2-positive MBC or symptomatic CNS metastases. Treatment is continued until progression, unacceptable toxicity, or refusal. Dose interruption/reduction is implemented if pts experience grade 2–4 clinically relevant adverse events. Results: The current interim analysis includes the first 60 pts, with median age 55 years (range 33–79) in the Xcont arm and 67 years (range 34–88) in the Xint arm. 26% and 14%, respectively, were hormone receptor negative. Prior chemotherapy included a taxane in 48% vs 52% and an anthracycline in 65% vs 76%, respectively. X was given as first-line chemotherapy in 48% and 38% of pts, respectively. Median duration of treatment was 7 cycles for Xcont vs 6 cycles for Xint. Dose reduction was required in 10% of cycles in each arm. Toxicity led to treatment discontinuation in 1 vs 8 pts, respectively. Activity and safety results at interim analysis are summarized below (Table). Conclusions: Xcont and Xint seem similarly active in MBC in this interim analysis. Xcont appeared slightly better tolerated. The study will continue recruiting additional pts. [Table: see text] No significant financial relationships to disclose.
Predicting response to second-line trastuzumab-based therapy in patients (pts) with HER2-positive advanced breast cancer (ABC)
Authors: Bartsch R. , Wenzel C. , Pluschnig U. , Dubsky P. , Gampenrieder S. P. , Rudas M. , Mader R. , Gnant M. , Zielinski C. C. , Steger G. G. 
Published: August 2020

1090 Background: In HER2-positive ABC, the upfront use of trastuzumab (T) is well established. Following progression upon first-line therapy, pts may be switched to lapatinib. Others however may be candidates for continued antibody therapy. Finding the optimal treatment approach therefore is pertinent. Here, we aimed to identify factors predicting response to second-line T-based therapy. Methods: 80 pts (median age 50.5 years) with ABC treated with >1 line of T-containing therapy were identified from a breast cancer database. HER-2-status was determined by immunohistochemistry (HercepTest) and re-analyzed by FISH if a score of 2+ was gained. Response rate (RR; CR+PR), clinical benefit rate (CBR; CR+PR+SD >6 months), time to progression (TTP), overall survival (OS), and cardiac toxicity were recorded. Response was evaluated every three months (m) using UICC criteria. TTP and OS were estimated using the Kaplan-Meier product limit method. In order to identify factors associated with TTP, the following variables were included in a Cox regression model: age (≤65 y/>65 y), initial tumor stage (<IV/IV), grading, ductal/lobular carcinoma, endocrine receptor status, prior non T-containing palliative chemotherapy, metastatic sites (visceral/non-visceral only), and clinical benefit (CB) from T-based first-line therapy. The same variables were used in a multinomial logistic regression model to evaluate their influence on treatment response. P values <0.05 were considered to indicate statistical significance. Results: Median time of observation was 28 m. TTP was median 9.3 m (95% CI 7.73–10.96) in the first-line and 7.5 m (95% CI 6.14–8.82) in the second-line setting (n.s.). First-line treatment yielded an 83% CBR, as compared to 54% in second-line. None of the factors included in the multivariate model independently predicted outcome. A significant deterioration of cardiac function was observed in a single patient; 22.5% developed brain metastases. Conclusions: T in multiple lines showed considerable activity. None of the variables investigated could independently predict response to second-line therapy. In order to reliably predict activity of second-line T-based therapy evaluation of other factors such as truncated HER2 or PTEN-loss appears necessary. [Table: see text]
Use of multiplex mutation genotyping to identify novel and protective mutations in breast cancer
Authors: Kalinsky K. , Jacks L. M. , Hedvat C. , Bhanot U. , Patil S. , Heguy A. , Asher M. , Drobnjak M. , Hudis C. , Moynahan M. E. 
Published: August 2020

11004 Background: We recently analyzed 590 primary invasive breast tumors for PIK3CA mutations by multiplex massARRAY genotyping. We identified a 32.5% PIK3CA mutation rate (manuscript submitted). Associations between PIK3CA mutation status and favorable pathology, such as lower grade tumors, lymph node negativity and hormone receptor (HR) positivity, were observed. Multiplex analysis allows the rapid assessment of mutations not commonly described in breast cancer. To identify activated pathways that may serve as predictive biomarkers, tissue microarrays (TMA) underwent immunohistochemical (IHC) analysis. Methods: 590 archival formalin-fixed paraffin embedded (FFPE) tumors > 1 cm were used to ensure adequate tissue procurement for mutation detection and TMA construction. MassARRAY (Sequenom) genotyping was performed on native DNA to identify PIK3CA, RAS, RET, and other known mutations. IHC staining of the TMAs included assessment of steroid nuclear receptors, HER2 expression, Akt pathway activation (including pAKT, p70S6K, eIF4E), and PTEN. Stained TMAs underwent digital quantitative image analysis and scoring (Aperio, Vista, CA). The Kaplan-Meier method and Cox models were used in univariate and multivariate analysis for associations of mutation status and clinicopathologic features on overall survival (OS) and breast cancer-specific survival (BCSS). Results: Compared to wild-type, PIK3CA mutated tumors (median f/u: 12.8 years) demonstrate a significant improvement in OS (p=0.03) and BCSS (p=0.004). For patients with any PIK3CA mutation, the improvement in BCSS is maintained in HR positive and ER negative subgroups. In addition to PIK3CA mutations, RAS and RET mutations are identified in a small proportion of breast tumors. Additional analysis to evaluate the association of mutation status and biomarker data derived from the TMA analysis will be performed for meeting presentation. Conclusions: We have recently defined the positive prognostic significance of PIK3CA mutations in breast cancer. RAS mutations are confirmed to occur rarely in breast cancer. The finding of RET mutations in breast cancer is novel. Future tumor biomarker identification directed towards predictive measurement will assist in tailoring therapy to appropriate patient populations. No significant financial relationships to disclose.
Performance of a blood-based gene-expression test, BCtect, for early breast cancer detection
Authors: Tobin D. , Bårdsen K. , Kauczynska M. , Kumar Y. , Shroff C. , Punia D. , Srinivasan V. , Børresen Dale A. , Sharma P. , Hollingsworth A. 
Published: August 2020

11012 Background: We report the development of a gene expression based blood test to detect breast cancer (BC). Validation of the test has been performed in multiethnic populations (European/US and Indian). Here we report findings from a multi-centre validation study. Methods: In a multicentre-study, blood samples were collected from women recruited in 4 groups 1) early stage BC, 2) late stage BC, 3) benign breast lesions, 4) without abnormal mammographic findings. Samples were collected in PAXgene tubes and shipped to a central laboratory where RNA extraction and quality control were performed. Gene expression analysis was performed using TaqMan low density arrays containing a BC-specific gene signature in a 96-gene assay format. The overall gene expression pattern was converted to a test score which was used to classify the subject as positive or negative for BC. A total of 442 samples were used to develop an India specific algorithm and estimate its prediction efficacy. Samples were divided into a training cohort (N=292) and a test cohort (N=150). The performance of the test was determined from the class of the independent test cohort. Results: The model correctly predicted the class of 110/150 test samples, resulting in an overall accuracy of 73%. Performance was similar for early and late stage cancer and for benign and healthy (no mammographic findings). No significant difference in diagnostic performance was seen between pre- (57/75 correctly predicted) and post-menopausal (53/75 correctly predicted) women indicating the clinical value of our test in younger women. No statistical correlation between correct/false test score and body mass index was noted. Lesion size varied from 8mm diameter to 120mm. No statistical correlation of the test score was seen with lesion size in this cohort. Conclusions: The blood based gene expression test showed similar diagnostic performance between women with early and late stage BC, and the test was independent of the subject's BMI and menopausal status suggesting broad applicability of the test and indicating its clinical potential in younger women where mammography is of less value due to dense breast tissue. No correlation with lesion size was seen suggesting the lower limit of detection is below 8mm. [Table: see text]
Semi-quantitative protein analysis of HER2 and ER levels in human breast cancer reveals broad expression ranges within HER2+ and ER+ phenotypes
Authors: Liotta L. , Pierobon M. , Wulfkuhle J. , Laird J. , Livasy C. , Espina V. , Esserman L. , Petricoin E. 
Published: August 2020

11014 Background: ER and HER2 measurements underpin a majority of breast cancer clinical testing, yet determination of ER and HER2 protein levels are routinely performed using subjective approaches. We have developed a semi-quantitative calibrated protein microarray, the Reverse Phase Protein Microarray (RPMA), to more adequately determine accurate and precise protein expression levels in clinical tissue specimens. We utilized this method to determine HER2 and ER expression levels and compared the results to those values reported from the clinical laboratory. Methods: Pure tumor epithelium from 149 frozen pre-treatment human breast cancer tissue specimens (from the I-SPY TRIAL: CALGB 150007/150012, ACRIN 6657) were procured via Laser Capture Microdissection and protein pathway mapping was performed whereby the ER (N=112) and HER2 (N= 118) levels were directly measured and compared with reported IHC values. Results: Overall, RPMA measurements of HER2 had excellent correlation with IHC and FISH HER2 determination with no IHC or FISH false positives (88/88). 7 out of 30 of the FISH/IHC+ cases were found by RPMA to have HER2 values as low or lower than the FISH/IHC- cases with the HER2+ population having RPMA expression levels that varied by as much as 10-fold. There was less concordance between RPMA ER values and IHC ER values. Detailed analysis of a more homogeneous ER+ population (Allred =8) revealed a large dynamic range of expression of ER (10–20 fold) by RPMA. The HER2 and ER RPMA results were independently validated by Western Blot using a separate biopsy. Conclusions: Discreet protein expression values obtained by RPMA for ER and HER2 reveal distinctly broad expression values, with as much as 10–20 fold dynamic range in expression, even in a homogeneous (e.g. Allred score of 8) population. Such dynamic differences in protein expression may produce dramatic effects in therapeutic response rate. These findings, if found to be clinically useful, point to a potential need for more fine-tuned protein expression determination by quantitative high-throughput technologies for patient stratification even for standard-of-care FDA approved therapies. [Table: see text]