Abstract P4-04-05: Molecular subtyping reveals the heterogeneity of metaplastic breast cancers

Introduction: Metaplastic breast carcinoma (MBC) is a rare (1%) and aggressive histological special type of breast cancer, which often (>90%) displays a triple-negative (TN) phenotype. Microarray-based gene expression classifications of breast cancer have been described, including the ‘intrinsic subtypes’ (i.e. luminal A, luminal B, basal-like, HER2-enriched, normal breast-like and claudin-low) and the six TN molecular subtypes with therapeutic implications in preclinical models (i.e. basal-like I, basal-like II, mesenchymal-like, mesenchymal stem-like, immunomodulatory and luminal androgen receptor). In addition, single nucleotide polymorphism (SNP) array analyses have led to the development of classifiers to define whether TN breast cancers would have genomic aberrations consistent with those found in tumors arising in BRCA1 germline mutation carriers. Here we sought to define i) the heterogeneity of MBCs using distinct microarray-based classifiers and ii) whether MBCs display gene copy number profiles consistent with those of BRCA1 breast cancers.

Material and Methods: Thirty consecutive MBCs were retrieved from the tumor banks of the authors’ institutions, reviewed by two pathologists and classified into three groups: carcinomas with spindle cell metaplasia (n = 12), with squamous metaplasia (n = 10), and with heterologous elements (n = 8). RNA and DNA were extracted from representative frozen sections containing >50% of cancer cells from each tumor and subjected to gene expression profiling using the HumanHT-12 v4 platform (Illumina) and gene copy number analysis using SNP 6.0 arrays (Affymetrix), respectively. ‘Intrinsic subtyping’ was performed according to the UNC guidelines, and subtyping into the six TN types using a dedicated website (https://cbc.mc.vanderbilt.edu/tnbc/). Classification of MBCs into BRCA1-like or non-BRCA1-like was performed using an algorithm to identify and quantify large-scale state transitions.

Results: PAM50/claudin-low subtyping of MBCs revealed that all spindle cell carcinomas (n = 12) were consistently of claudin-low subtype, whereas MBCs with heterologous elements were classified as of basal-like (n = 6) and normal breast-like (n = 2), and squamous cell carcinomas as of basal-like (n = 5), claudin-low (n = 4) and normal-like (n = 1). Using the six TN subtypes, spindle cell MBCs were classified as mesenchymal stem-like (n = 4), immunomodulatory (n = 3), basal-like 2 (n = 3), or mesenchymal (n = 2) subtype. Carcinomas with heterologous elements were classified as basal-like 1 (n = 5) or mesenchymal (n = 3) subtype, whereas carcinomas with squamous metaplasia were of immunomodulatory (n = 5), basal-like 1 (n = 2), basal-like 2 (n = 2) or mesenchymal (n = 1) subtype. Out of the 26 samples where SNP 6.0 arrays were successfully performed, only 9 (35%) were classified as BRCA1-like, including two spindle cell carcinomas, two carcinomas with heterologous elements and five carcinomas with squamous metaplasia.

Conclusion: MBCs constitute a heterogeneous group of tumors and the histological subclassification of these cancers is of importance, given that tumors with distinct metaplastic elements are classified differently according to current molecular subtyping methods. Only 35% of MBCs display BRCA1-like patterns of gene copy number aberrations.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-04-05.

Abstract P4-04-08: Genomic and transcriptomic characterization of papillary carcinomas of the breast

Introduction: Papillary carcinomas (PCs) are a rare (<1%) special histological type of breast cancer that often affects postmenopausal women, and has an overall favorable outcome. Based on their histological characteristics, these tumors are classified into three different subtypes, namely encapsulated papillary carcinomas (EPC), solid papillary carcinomas (SPC) and invasive papillary carcinomas (IPC). In this study, we sought i) to investigate whether PCs constitute a molecular entity distinct from grade- and ER-matched invasive ductal carcinomas of no special type (IDC-NST) at the transcriptomic level, ii) to investigate whether EPC, SPC and IPC display distinct transcriptomic profiles, iii) to characterize the repertoire of copy number alterations in the different subtypes of PC, and iv) to identify recurrent fusion genes that may be potential drivers of this disease.

Material and methods: DNA and RNA were extracted from microdissected PCs (4 SPCs, 5 IPCs and 7 EPCs) and grade- and ER-matched IDC-NSTs (RNA only). 16 PCs and 16 grade- and ER-matched IDC-NSTs were subjected to gene expression profiling using the Illumina Human HT-12 v4 platform. Genes differentially expressed between the PC subtypes were identified using SAM, and functional annotation of these genes was performed using DAVID. Intrinsic molecular subtypes were determined using the PAM50 single sample predictor. Copy number profiling was performed using Affymetrix Human SNP 6.0 arrays with DNA extracted from 16 PCs. In addition, 8 PCs (3 IPCs, 3 EPCs, 2 SPCs) were subjected to paired-end massively parallel RNA sequencing (Illumina GAIIx). Putative expressed fusion transcripts were identified using validated algorithms (i.e. deFuse and Chimerascan), and confirmed by reverse transcription PCR.

Results: PCs were preferentially of histological grade I/II (82%) and ER-positive (100%). Unsupervised analysis revealed that PC subtypes show a high degree of similarity at the transcriptomic level, and form clusters distinct from grade- and ER-matched IDC-NSTs. Compared with IDC-NSTs, PCs displayed reduced expression of genes related to cell motility, adhesion and extracellular matrix. PAM50 subtyping classified 87.5%, 50% and 100% of EPCs, SPCs and IPCs as of luminal subtypes, respectively. 12.5% of EPCs were classified as of basal-like subtype, and 50% of SPCs as of HER2-enriched subtype. At the genomic level, PC subtypes displayed similar patterns of gene copy number aberrations. Five in-frame fusion genes, USF1-CCDC38, MDC1-SFTA2, DLD-LMBR1, PDCL-DENND1A and SUGT1-NOL6, were identified and validated in PCs, however none of these were recurrent in the cases included in this study.

Conclusion: Our results demonstrate that the majority of PCs are of luminal subtype, and support the contention that at the transcriptomic level, PCs are distinct from grade- and ER-matched IDC-NSTs. Our findings also demonstrate that unlike some other histological special types of breast cancer, PCs are not underpinned by a highly recurrent expressed fusion gene.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-04-08.

Search for bottomonium states in exclusive radiative Υ(2S) decays

We search for bottomonium states in Υ(2S) → (bb)γ decays with an integrated luminosity of 24.7  fb(-1) recorded at the Υ(2S) resonance with the Belle detector at KEK, containing (157.8±3.6)×10(6) Υ(2S) events. The (bb) system is reconstructed in 26 exclusive hadronic final states composed of charged pions, kaons, protons, and K(S)(0) mesons. We find no evidence for the state recently observed around 9975 MeV (X(bb)) in an analysis based on a data sample of 9.3×10(6) Υ(2S) events collected with the CLEO III detector. We set a 90% confidence level upper limit on the branching fraction B[Υ(2S) → X(bb)γ] × ∑(i)B[X(bb) → h(i)] < 4.9×10(-6), summed over the exclusive hadronic final states employed in our analysis. This result is an order of magnitude smaller than the measurement reported with CLEO data. We also set an upper limit for the ηb(1S) state of B[Υ(2S) → ηb(1S)γ] × ∑(i)B[ηb(1S) → h(i)] < 3.7×10(-6).

How we identify and count Aboriginal people--does it make a difference in estimating their disease burden?

INTRODUCTION

We examined the concordance between the Canadian Community Health Survey (CCHS) "identity" and "ancestry" questions used to estimate the size of the Aboriginal population in Canada and whether the different definitions affect the prevalence of selected chronic diseases.

METHODS

Based on responses to the "identity" and "ancestry" questions in the CCHS combined 2009-2010 microdata file, Aboriginal participants were divided into 4 groups: (A) identity only; (B) ancestry only; (C) either ancestry or identity; and (D) both ancestry and identity. Prevalence of diabetes, arthritis and hypertension was estimated based on participants reporting that a health professional had told them that they have the condition(s).

RESULTS

Of participants who identified themselves as Aboriginal, only 63% reported having an Aboriginal ancestor; of those who claimed Aboriginal ancestry, only 57% identified themselves as Aboriginal. The lack of concordance also differs according to whether the individual was First Nation, Métis or Inuit. The different method of estimating the Aboriginal population, however, does not significantly affect the prevalence of the three selected chronic diseases.

CONCLUSION

The lack of concordance requires further investigation by combining more cycles of CCHS to compare discrepancy across regions, genders and socio-economic status. Its impact on a broader list of health conditions should be examined.

Precision measurement of charged pion and kaon differential cross sections in e+ e- annihilation at sqrt[s]=10.52 GeV

Measurements of inclusive differential cross sections for charged pion and kaon production in e+ e- annihilation have been carried out at a center-of-mass energy of sqrt[s]=10.52  GeV. The measurements were performed with the Belle detector at the KEKB e+ e- collider using a data sample containing 113×10(6) e+ e- → qq events, where q={u,d,s,c}. We present charge-integrated differential cross sections dσ(h±)/dz for h±={π±,K±} as a function of the relative hadron energy z=2E(h)/sqrt[s] from 0.2 to 0.98. The combined statistical and systematic uncertainties for π± (K±) are 4% (4%) at z∼0.6 and 15% (24%) at z∼0.9. The cross sections are the first measurements of the z dependence of pion and kaon production for z>0.7 as well as the first precision cross section measurements at a center-of-mass energy far below the Z0 resonance used by the experiments at LEP and SLC.

An investigation of factors that influence general practitioners' referral of computed tomography scans in patients with headache

AIM

In assessing patients with headaches, general practitioners (GPs) play an important role in determining which patients require computed tomography (CT) scans. The purpose of this study was to identify factors that influence GPs' decisions to refer CT scans for patients with headaches.

MATERIALS AND METHODS

A self-administered survey was presented to GPs in Western Australia. One hundred and twenty-eight vignettes describing patients who may have required CT referral for headache were constructed encompassing six clinical variables. Nine vignettes, selected at random, were presented to each respondent. Respondents were asked if they would refer the patient for diagnostic imaging tests, if so, which imaging modalities would they request, how urgently and the perceived benefits of the requested imaging modality. Multinomial logistic regression was used for the multivariate analysis.

RESULTS

We received 105 completed questionnaires (21%). GPs were more likely to refer patients with headaches for diagnostic imaging and CT scans in the following clinical scenarios: patients with a history of colorectal cancer and epilepsy; and patients feeling unwell for the past 6 weeks and headache being exacerbated with valsalva manoeuvrers. Private health insurance and other respondent demographics such as GPs experience and site of care increased imaging referral.

CONCLUSION

GP's referral decisions of diagnostic imaging and CT examinations for patients with headaches are dependent on clinical scenarios and the likelihood of a significant pathology. Further research is required to identify the significant clinical findings with regard to the CT referrals and ensure that CT scans are not requested in patients who are unlikely to benefit.

Search for an H-dibaryon with a mass near 2mΛ in Υ(1S) and Υ(2S) decays

We report the results of a high-statistics search for H dibaryon production in inclusive Υ(1S) and Υ(2S) decays. No indication of an H dibaryon with a mass near the M(H)=2m(Λ) threshold is seen in either the H→Λpπ(-) or ΛΛ decay channels and 90% confidence level branching-fraction upper limits are set that are between one and two orders of magnitude below the measured branching fractions for inclusive Υ(1S) and Υ(2S) decays to antideuterons. Since Υ(1S,2S) decays produce flavor-SU(3)-symmetric final states, these results put stringent constraints on H dibaryon properties. The results are based on analyses of 102 million Υ(1S) and 158 million Υ(2S) events collected with the Belle detector at the KEKB e(+)e(-) collider.

Evidence for B- → τ- ν(τ) with a hadronic tagging method using the full data sample of Belle

We measure the branching fraction of B- → τ- ν(τ) using the full Υ(4S) data sample containing 772×10(6) BB pairs collected with the Belle detector at the KEKB asymmetric-energy e+ e- collider. Events with BB pairs are tagged by reconstructing one of the B mesons decaying into hadronic final states, and B- → τ- ν(τ) candidates are detected in the recoil. We find evidence for B- → τ- ν(τ) with a significance of 3.0 standard deviations including systematic errors and measure a branching fraction B(B- → τ- ν(τ))=[0.72(-0.25)(+0.27)(stat)±0.11(syst)]×10(-4).

Kava for the treatment of generalized anxiety disorder RCT: analysis of adverse reactions, liver function, addiction, and sexual effects

Presently, little is known about a number issues concerning kava (Piper methysticum), including (i) whether kava has any withdrawal or addictive effects; (ii) if genetic polymorphisms of the cytochrome (CYP) P450 2D6 liver enzyme moderates any potential adverse effects; and (iii) if medicinal application of kava has any negative or beneficial effect on sexual function and experience. The study design was a 6-week, double-blind, randomized controlled trial (n = 75) involving chronic administration of kava (one tablet of kava twice per day; 120 mg of kavalactones per day, titrated in non-response to two tablets of kava twice per day; 240 mg of kavalactones) or placebo for participants with generalized anxiety disorder. Results showed no significant differences across groups for liver function tests, nor were there any significant adverse reactions that could be attributed to kava. No differences in withdrawal or addiction were found between groups. Interesting, kava significantly increased female's sexual drive compared to placebo (p = 0.040) on a sub-domain of the Arizona Sexual Experience Scale (ASEX), with no negative effects seen in males. Further, it was found that there was a highly significant correlation between ASEX reduction (improved sexual function and performance) and anxiety reduction in the whole sample.

Abstract PD05-08: Genomic characterisation of invasive breast cancers with heterogeneous HER2 gene amplification

Aims: HER2 gene amplification is observed in up to 15% of breast carcinomas. In a rare subset of breast cancers classified as HER2-positive by immunohistochemistry and in situ hybridisation, HER2 overexpression and gene amplification are restricted to a subset of &gt;30% but not all cancer cells. Here we sought to characterise the repertoire of gene copy number aberrations and somatic mutations in the HER2-positive and HER2-negative components of cases with heterogeneous HER2 overexpression and gene amplification.

Material and methods: Cases diagnosed as HER2 positive but with &gt;30% but &lt;100% of cells displaying HER2 overexpression were retrieved from the authors' institutions. HER2 heterogeneity status was re-assessed using immunohistochemistry and chromogenic and/ or fluorescence in situ hybridisation. For cases with confirmed HER2 gene amplification heterogeneity, HER2-positive and HER2-negative components were microdissected from tissue sections stained with the Herceptest antibody. DNA samples extracted from both components of each case were subjected to microarray-based comparative genomic hybridisation (aCGH), using a 32K BAC array platform with 50Kb resolution. The HER2-positive and HER2-negative components of cases with frozen material were also subjected to massively parallel targeted exome sequencing.

Results: Twelve cases yielded sufficient DNA for aCGH analysis. Tumours were preferentially ER positive (83%) and of histological grade 3 (67%). The HER2-positive and HER2-negative components of all cases shared most of the copy number aberrations. A pairwise comparison of the genomic profiles of the two components from each case revealed that in ten of the twelve cases, copy number aberrations in addition to 17q12 amplification encompassing the HER2 gene locus were restricted to one of the two components. Exome sequencing of two cases suggested that the HER2-positive and HER2-negative components from each case harboured &gt;30 somatic mutations in common, including identical TP53 somatic mutations in both components of each case. The HER2-negative component of one of the cases displayed a somatic mutation in NRG2, an ERBB receptor ligand, and the HER2-negative component of the other case harboured a mutation in PTTG1IP, a proto-oncogene with putative oestrogen receptor elements.

Conclusions: Our results demonstrate that in HER2-positive breast cancers with heterogeneous HER2 gene amplification, the HER2-positive and HER2-negative components are clonally related. The distinct genomic profiles of HER2-positive and HER2-negative components, however, suggest that, at least in some of these cases, HER2 amplification may constitute a relatively late event in tumour evolution. Exome sequencing revealed mutations restricted to the HER2-negative components of HER2-positive tumours with heterogeneous HER2 overexpression/gene amplification, which may constitute potential drivers in the absence of HER2 overexpression/gene amplification.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr PD05-08.

Evidence for the η(b)(2S) and observation of h(b)(1P)→η(b)(1S)γ and h(b)(2P)→η(b)(1S)γ

We report the first evidence for the η(b)(2S) using the h(b)(2P)→η(b)(2S)γ transition and the first observation of the h(b)(1P)→η(b)(1S)γ and h(b)(2P)→η(b)(1S)γ transitions. The mass and width of the η(b)(1S) and η(b)(2S) are measured to be m(η(b)(1S))=(9402.4±1.5±1.8) MeV/c(2), m(η(b)(2S))=(9999.0±3.5(-1.9)(+2.8)) MeV/c(2), and Γ(η(b)(1S))=(10.8(-3.7-2.0)(+4.0+4.5)) MeV. We also update the h(b)(1P) and h(b)(2P) mass measurements. We use a 133.4 fb(-1) data sample collected at energies near the Υ(5S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider.

Analysis of mechanisms of Cisplatin resistance in 3 pairs of human tumor-cell lines expressing normal and resistant responses to Cisplatin

Three pairs of human tumour cell Lines each having a cisplatin sensitive parental cell line (normal) and a cisplatin resistant derivative were tested for their cisplatin responses and expression for three reputed mechanisms of resistance. In each case, the derivative cell lines showed resistance to cisplatin when treated either in exponential or plateau growth phase. For both the resistant and the normal cell line there was greater resistance to cisplatin treatment when cells were treated in exponential growth phase. Mechanisms of resistance were expressed in all three resistant variants. The cervical carcinoma resistant variant expressed higher GSH levels and lower cisplatin uptake levels but not elevated polymerase levels. The other two variant cell lines for the glioma and the lung cancer expressed all three of the mechanisms (increased GSH, decreased cisplatin uptake and increased polymerases) associated with resistance. There was no correlation to the level of resistance expressed and the number of mechanisms expressed but the change in response of the parental line to becoming a resistant variant may be related to the basal level of expression of some of the factors that are associated with resistance.

Radiosensitization by Cisplatin treatment in Cisplatin-resistant and sensitive human ovarian-carcinoma cell-lines

The responses of cisplatin resistant (A2780(cp)) and cisplatin sensitive (A2780) ovarian carcinoma cell lines to radiation, cisplatin and cisplatin plus radiation have been studied. The cisplatin resistant cell line showed cross resistance to radiation. When cells were exposed to 2 mu g/ml of cisplatin treatment for one hour radiosensitization was achieved. The degree of radiosensitization was treatment sequence dependent. Irradiation followed by cisplatin treatment resulted in synergistic interaction with dose modifying factors (DMFs) as high as 1.5 in the resistant line and 1.1 in the sensitive line. The reverse sequence resulted in antagonistic interaction with DMFs of 0.8 to 0.9 at the 10% survival level. At lower survival levels the interaction remained antagonistic for the resistant cell line. Increasing the cisplatin concentration to 4 mu g/ml did not increase the degree of cisplatin radiosensitization. Simultaneous treatment of irradiation during the middle of a one or two hour cisplatin treatment did not increase the degree of radiosensitization. The cisplatin resistant cell line had a much greater cisplatin radiosensitization effect than the sensitive parental cell line with maximum DMFs for the resistant cell line ranging from 0.9-1.5 and for the sensitive cell line from 0.8-1.1. These results indicate that cisplatin may be an effective radiosensitizer especially in cisplatin resistant cell lines. This effect may be related to the inhibition of repair of radiation damage which may be elevated as a mechanism of resistance in the resistant cell line.

Observation of new resonant structures in γγ → ωϕ, ϕϕ, and ωω

The processes γγ → ωϕ, ϕϕ, and ωω are measured using an 870  fb(-1) data sample collected with the Belle detector at the KEKB asymmetric-energy e+ e- collider. Production of vector meson pairs is clearly observed and their cross sections are measured for masses that range from threshold to 4.0 GeV. In addition to signals from well established spin-zero and spin-two charmonium states, there are resonant structures below charmonium threshold, which have not been previously observed. We report a spin-parity analysis for the new structures and determine the products of the η(c), χ(c0), and χ(c2) two-photon decay widths and branching fractions to ωϕ, ϕϕ, and ωω.

The acute effects of kava and oxazepam on anxiety, mood, neurocognition; and genetic correlates: a randomized, placebo-controlled, double-blind study

RATIONALE

Kava (Piper methysticum) is a psychotropic plant medicine with history of cultural and medicinal use. We conducted a study comparing the acute neurocognitive, anxiolytic, and thymoleptic effects of a medicinal dose of kava to a benzodiazepine and explored for the first time specific genetic polymorphisms, which may affect the psychotropic activity of phytomedicines or benzodiazepines.

METHODS

Twenty-two moderately anxious adults aged between 18 and 65 years were randomized to receive an acute dose of kava (180 mg of kavalactones), oxazepam (30 mg), and placebo 1 week apart in a crossover design trial.

RESULTS

After exposure to cognitive tasks, a significant interaction was revealed between conditions on State-Trait Anxiety Inventory-State anxiety (p = 0.046, partial ŋ² = 0.14). In the oxazepam condition, there was a significant reduction in anxiety (p = 0.035), whereas there was no change in anxiety in the kava condition, and there was an increase in anxiety in the placebo condition. An increase in Bond-Lader "calmness" (p = 0.002) also occurred for the oxazepam condition. Kava was found to have no negative effect on cognition, whereas a reduction in alertness (p < 0.001) occurred in the oxazepam condition. Genetic analyses provide tentative evidence that noradrenaline (SLC6A2) transporter polymorphisms may have an effect on response to kava.

CONCLUSION

Acute "medicinal level" doses of this particular kava cultivar in naive users do not provide anxiolytic activity, although the phytomedicine also appears to have no negative effects on cognition.