Citations

Abstract NSC 373981 is 1-ethanol, 2-nitro-naphtho[2,1-b]furan that has demonstrated activity in the NCI60 anticancer screen and in the mouse hollow-fiber assay. Growth inhibitory activity was also observed in several xenograft models. There is some evidence that antitumor activity is greater in vivo than would be predicted by the in vitro results, suggesting the possibility of activating metabolism. While the mechanism of anticancer activity is unknown, naphthofurans have been reported to modulate certain nuclear receptors. The purpose of this study was to characterize the plasma pharmacokinetics of NSC 373981 following i.v. and i.p. administration to athymic nude mice and to characterize potential metabolites of this compound in plasma, urine, and bile. We developed and validated suitable positive ionization LC/MS/MS methodology for measuring NSC 373981 that utilized liquid extraction with 1-chlorobutane and MS/MS detection with the 258>212 and 244>169 transitions, respectively, for NSC 373981 and NSC 329226, an analog that was used as the internal standard. Baseline separations were achieved on a Polaris C18 column under a mobile phase consisting of 70:30 methanol:water containing 0.1% formic acid. Standard curves were linear over the concentration range 2.5-1000 ng/mL with a lower limit of detection of 2.5 ng/mL. NSC 373981 was stable under acidic, neutral and basic conditions, as well as human and mouse plasma during 24-hr incubation at 37°C. NSC 373981 pharmacokinetics were characterized in male nu/nu mice after a 37.5 mg/kg i.v. dose or a 150 mg/kg i.p. dose. Plasma, bile, urine and feces were collected for 24-hr after drug administration. Following i.v. administration, the peak concentration was > 5.9 μg/mL and the terminal elimination half-life was 1.2 hours. Volume of distribution and plasma clearance values were 694 ml and 390 mL/hr, respectively. Following i.p. administration, NSC373981 reached a peak concentration of 2.1 μg/mL at 15 minutes and the terminal elimination half-life was 36.8 hours. The i.p. bioavailability of NSC373981 was 58%. In vivo metabolite profiles were characterized in plasma, urine, feces, and bile. We detected several Phase I metabolites in these samples including those produced by reduction of the aromatic nitro group, oxidation of the primary alcohol moiety on the reduced metabolite, oxidation of the primary alcohol moiety, benzylic hydroxylation, hydroxylation and dihydrodiol formation on the naphthalene moiety, and Phase II metabolites including glucuronidation of the carboxylic acids and a glutathione metabolite of hydroxylated NSC 373981. Supported by NCI contract N01-CM-2011-00014. Citation Format: Joel M. Reid, Sarah A. Buhrow, Renee M. McGovern, Joseph M. Covey, Matthew M. Ames. Pharmacokinetics and in vivo metabolism of the naphthofuran NSC373981 in male nu/nu mice. [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 2462. doi:10.1158/1538-7445.AM2013-2462

Abstract Purpose: The therapeutic potential of PARP inhibitors is predicted to extend beyond BRCA mutant phenotypes to homologous recombination (HR)-deficient cancers. Response of individual ovarian cancers to niraparib was characterized using treatment naïve, patient-derived tumorgraft models and correlated with predicted HR status and gene expression profile. Methods: Utilizing a living tumor bank of patient-derived ovarian xenografts (PDXs), niraparib (MK-4827) was evaluated in five high-grade ovarian cancer tumorgrafts (PDX077, PDX087, PDX039, PDX080 and PDX95) as monotherapy, combination with carboplatin ± paclitaxel and maintenance therapy. Intraperitoneal tumorgrafts were monitored for tumor growth with twice-weekly transabdominal ultrasound imaging. In vivo response to niraparib was correlated to massively parallel sequencing data (BROCA) for HR genes and with each source patient's platinum response. Tumorgrafts were accordingly classified into predicted HR-proficient and HR-deficient phenotypes. PARP1 and poly(ADP-ribose) polymer (pADPr) expression as well as gene expression by DNA microarray were compared between treatment and control tumor replicates, and HR-deficient vs. HR-proficient tumors. Results: PDX077 (verified to harbor a somatic BRCA2 mutation (predicted HR deficient)) and PDX039 without any HR mutations detected by BROCA (predicted HR proficient) both responded to niraparib monotherapy and combination therapy in vivo (p=0.002 and 0.009 for treated vs. control groups, respectively). Significant growth attenuation, but not regression, in response to single agent treatment was demonstrated in PDX080 (CDK12 mutation; predicted HR-deficient; p=0.02 vs. control). In comparison, a BRCA2-mutant model (PDX095) failed to respond to niraparib monotherapy (p=0.97). As predicted, niraparib was not active as a single agent or in combination with chemotherapy in a BRCA wild-type, predicted HR-proficient tumorgraft (PDX087; p=not significant). Niraparib enhanced tumor regression with carboplatin but not with paclitaxel/carboplatin in an HR-deficient tumorgraft (PDX077), and maintenance niraparib therapy was effective in prolonging recurrence-free survival. pADPr inhibition was demonstrated in all niraparib-treated tumorgrafts, while PARP1 degrada-tion was evident in tumorgrafts responsive to single agent niraparib. Differential gene expression was seen in niraparib treated vs. control tumors in HR-deficient tumorgrafts in comparison to HR-proficient tumors at the end of 4 weeks of treatment. Clustering of 6 most/least differentially expressed genes was predictive of response to niraparib. Furthermore, RAD51C and PTEN gene expression were diminished in PDX039 (HR proficient by BROCA; niraparib responsive), suggesting a possible mechanism for its sensitivity to niraparib. Conclusion: Response to niraparib was seen in both BRCA-mutant and BRCA-wildtype xenografts. Thus, BRCA or HR gene mutational status alone was not sufficient to predict response to niraparib. Low RAD51C, PTEN and loss of PARP1 expression following treatment were most characteristic of tumors responding to niraparib. Paclitaxel may be detrimental to the sensitizing effects of PARP inhibition on carboplatin, which may have clinical implications for the incorporation of PARP inhibitors in front-line treatment. Our data are supportive of the phase III study of niraparib as maintenance therapy in patients with platinum-sensitive ovarian cancer. This abstract is also presented as Poster A30. Citation Format: Mariam Al Hilli, S. John Weroha, Marc Becker, Xiaonan Hou, Sean Harrington, Sarah McKinstrey, Kimberly Kalli, Karin Goodman, Keith Wilcoxen, Elizabeth Swisher, Scott Kaufmann, Paul Haluska. In vivo antitumor activity of the PARP inhibitor niraparib (MK-4827) in homologous recombination deficient and proficient ovarian cancer. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research: From Concept to Clinic; Sep 18-21, 2013; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2013;19(19 Suppl):Abstract nr PR05.

Abstract Background: Mucinous ovarian carcinomas (MC) and mucinous borderline ovarian tumours (MBOT) are associated with ERBB2 amplification and KRAS activating mutations. These events occur in a near-mutually exclusive pattern, and KRAS mutations are more prevalent in MBOTs than MC's whereas ERBB2 amplification is more frequently seen in MCs. Frequencies of mutations in other oncogenes and tumour suppressor genes in MC are not well established though TP53, BRAF, NRAS, and CDKN2A mutations have all been reported. As these carcinomas are commonly chemo-resistant a definitive molecular categorization of this subtype is needed as treatment options are explored. Methods: We undertook review of pathology reports and after exclusion of potential gastric, appendiceal or pancreatic involvement over 100 mucinous ovarian tumours were identified. HPV testing was undertaken to exclude rare metastasis from endocervical primary site. All specimens were assayed for p53 expression via TMA and subject to sequencing of common cancer gene hotspots using Ion-Torrent or Illumina MiSeq. Previously derived data on ERBB2 status was combined in our analysis and, where available, samples showing heterogeneity of ERBB2 amplification and any other Ras-pathway activating mutation were microdissected with components evaluated independently for concurrent hotspot mutations. Results: All samples were consistent with mucinous tumours of ovarian origin and none were HPV positive. We detected mutations in KRAS, BRAF, CDKN2A, TP53, PTEN, PIK3CA as well as presumed somatic/detrimental, variants in APC that have not previously been reported in mucinous tumours. Despite some samples having enriched tumour content, lower than expected allelic frequencies of KRAS activating mutations suggested intra-tumoural heterogeneity. This was consistent with results observed previously with rare ERBB2 amplification coinciding KRAS mutations. Conclusions: The prevalence of Ras-pathway mutations, especially amongst borderline lesions, suggests these mutations are critical for tumour onset. However varying allelic frequencies of KRAS mutations suggest progression to carcinoma is strongly influenced by other molecular features. Citation Format: Michael S. Anglesio, Robertson Mackenzie, Stefan Kommoss, Boris J. Winterhoff, Benjamin Kipp, Jaoquin Garcia, Jesse S. Voss, Kevin Halling, Sarah Kerr, Janine Senz, Winnie Yang, Magnus von Knebel Doeberitz, Elena-Sophie Prigge, Miriam Reuschenbach, Anna V. Tinker, Blake Gilks, Jamie N. Bakkum-Gamez, David G. Huntsman, Jessica N. McAlpine. Defining ovarian mucinous tumors: Cancer genes and heterogeneity. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research: From Concept to Clinic; Sep 18-21, 2013; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2013;19(19 Suppl):Abstract nr A18.

Abstract Background: In AI refractory MBC, TAM anti-tumor activity is limited (median PFS 4.5 months). In patients (pts) receiving TAM in the adjuvant and metastatic setting, breast cancer recurrence has been shown to differ based upon CYP2D6 genotype and Endx exposure. In collaboration with NCI, Z-Endx (NSC #750393) was synthesized and preclinical pharmacology studies demonstrated that oral Z- Endx resulted in > 20 fold Endx exposure compared to an equivalent dose of TAM and significantly greater anti-tumor activity than TAM in AI sensitive and resistant MCF7 xenografts. We conducted a phase I study of Z-Endx in women with ER+, AI refractory MBC to identify dose-limiting toxicities (DLT), a maximum tolerated dose (MTD) and a dose associated with steady state concentrations (Css) of ≥ 2 uM, based on the IC50 of recently identified Endx substrates: PKC and PI3K. Methods: Pts were enrolled to an accelerated titration schedule (2 pts/dose level) until moderate toxicity or DLT, and then to a 3+3 design. Z-Endx was administered orally once daily (28 day cycle). Eye exams were performed at baseline, end of cycle 2, and after 6 cycles. PK was performed on days 1-2, 3, 7, 14, and 28, and prior to subsequent cycles. Results: 23 women with AI refractory MBC (median 56 yrs, range 41-83) received Z-Endx once daily encompassing 7 dose levels (Table 1). The median number of prior chemotherapies and hormonal therapies in the metastatic setting were 2 and 2, respectively. Dose escalation continues at 160 mg/day and the MTD has yet to be determined. Cmax and AUC increased in a dose-dependent manner. A 20 and 100 mg/day dose yields Css of 0.39 and 2.48 uM, respectively. Significant anti-tumor activity was observed including 1 pt (100 mg/day) with a PR lasting 225 days; 1 pt (80 mg/day) with a 30% reduction in tumor size (PFS 169 days) and 2 pts (60 and 80 mg/day) with stable disease for >270 days. No eye toxicity was observed. Conclusions: In women with AI refractory MBC, the MTD of Z-Endx HCl has not been determined but Endx Css concentrations of > 2 uM and substantial anti-tumor activity has been observed. Following completion of the 160 mg/day dose, expansion at 20 and 100 mg/day will commence to perform translational studies and further characterize Endx pk. A randomized phase II examining two different doses of Z-Endx is planned in AI refractory MBC. Supported in part by CA 133049, CA69912, CA15083, CA116201, and CA15083. Table 1Dose Level (mg/day)Number of Treatment CyclesModerate or Severe Toxicities ReportedTumor ResponseProgression-free Survival (days)28 day Z-Endx Css (uM) 20 (n = 2)2; 3Gr 2 hot flashes (1 pt)----60; 850.39 40 (n = 2)2; 6noneStable (1 pt)61; 1670.66 60 (n = 6)1; 2; 2; 5; 8; 14Gr 4 Triglycerides (1 pt);Gr 3 thromboembolic event (1 pt); Gr 2 hot flashes, anemia, and hypoalbuminemia (1 pt)Stable (3 pts)125+; 56; 57; 132; 232; 4331.01 80 (n = 3)4; 6; 10Gr 2 hot flashesStable (3 pts)113; 169; 2961.61 100 (n = 3)1; 2; 8Gr 2 nausea (1 pt); Gr 2 irritability (1 pt)PR (1 pt)30; 56; 2252.48 120 (n = 3)1; 2; 4Gr 2 hypersomnia, paresthesia, and peripheral sensory neuropathy (1 pt)—39; 54; 1082.18 * Bold face toxicities occurred during cycle 1 Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr PD3-4.

Abstract Objectives: Cellular fibroepithelial lesions (CFELs) are a heterogeneous group of tumors encompassing cellular fibroadenoma (CFA) and phyllodes tumor (PT). Distinction between the two is challenging on core needle biopsy (CNB) specimens. The objective of this study was to evaluate histologic features that can help distinguish PT from CFA on CNB specimens. Methods: Records of all patients diagnosed with CFELs on CNB specimens with follow-up excision between January 2002 and December 2012 were retrieved. Histopathologic stromal features were evaluated on CNB specimens, including mitoses per 10 high-power fields (hpf), overgrowth, increased cellularity, fragmentation, adipose tissue infiltration, heterogeneity, subepithelial condensation, and nuclear pleomorphism. Results: Twenty-seven (42.2%) of 64 were diagnosed as PT (24 benign PTs and three borderline PTs) and 37 (57.8%) as CFA on excision. All features except for increased stromal cellularity were statistically significant. The average number of histologic features seen in PT and CFA was 3.9 and 1.4, respectively (odds ratio [OR], 7.27; 95% confidence interval [CI], 2.44–21.69; P = .0004). The average number of mitoses per 10 hpf was 3.0 for PT compared with 0.8 for CFA (OR, 2.14; 95% CI, 1.18–3.86; P = .01). Conclusions: The presence of mitoses (three or more) and/or total histologic features of three or more on CNB specimens were the most helpful features in predicting PT on excision.

ABSTRACT Genital human papillomavirus (HPV) is the etiologic agent of more than 99% of all cervical cancers worldwide, with 14 genotypes being considered oncogenic or “high risk” because of their association with severe dysplasia and cervical carcinoma. Among these 14 high-risk types, HPV-16 and -18 account for approximately 70% of cervical cancers. The aim of this study was to evaluate three FDA-approved HPV nucleic acid-based tests for the ability to predict high-grade cervical intraepithelial neoplasias (CIN2 or worse) in corresponding tissue biopsy specimens. Residual specimens (total n = 793, cervical n = 743, vaginal n = 50) collected in ThinPrep PreservCyt medium with a cytologic result of ≥atypical squamous cells of undetermined significance were tested by the Hybrid Capture 2 (HC2) assay (Qiagen, Gaithersburg, MD), the cobas HPV test (Roche Diagnostics, Indianapolis, IN), and the APTIMA HPV assay (Hologic, San Diego, CA). Genotyping for HPV-16 and HPV-18 was simultaneously performed by the cobas HPV test. Results were compared to cervical or vaginal biopsy findings, when they were available ( n = 350). Among the 350 patients with corresponding biopsy results, 81 (23.1%) showed ≥CIN2 by histopathology. The ≥CIN2 detection sensitivity was 91.4% by the cobas and APTIMA assays and 97.5% by HC2 assay. The specificities of the cobas, APTIMA, and HC2 assays were 31.2, 42.0, and 27.1%, respectively. When considering only positive HPV-16 and/or HPV-18 genotype results, the cobas test showed a sensitivity and a specificity of 51.9 and 86.6%, respectively. While the HC2, cobas, and APTIMA assays showed similar sensitivities for the detection of ≥CIN2 lesions, the specificities of the three tests varied, with the greatest specificity (86.6%) observed when the HPV-16 and/or HPV-18 genotypes were detected.

AbstractMosaic chromosomal abnormalities are relatively common. However, mosaicism may be missed due to multiple factors including failure to recognize clinical indications and order appropriate testing, technical limitations of diagnostic assays, or sampling tissue (s) in which mosaicism is either not present, or present at very low levels. Blood leukocytes have long been the “gold standard” sample for cytogenetic analysis; however, the culturing process for routine chromosome analysis can complicate detection of mosaicism since the normal cell line may have a growth advantage in culture, or may not be present in the cells that produce metaphases (the lymphocytes). Buccal cells are becoming increasingly utilized for clinical analyses and are proving to have many advantages. Buccal swabs allow for simple and noninvasive DNA collection. When coupled with a chromosomal microarray that contains single nucleotide polymorphic probes, analysis of buccal cells can maximize a clinician's opportunity to detect cytogenetic mosaicism. We present three cases of improved diagnosis of mosaic aberrations using buccal specimens for chromosomal microarray analysis. In each case, the aberration was either undetectable in blood or present at such a low level it likely could have gone undetected. These cases highlight the limitations of certain laboratory methodologies for identifying mosaicism. We also present practice implications for genetic counselors, including clinic workflow changes and counseling approaches based on increasing use of buccal samples.

Although ataxic dysarthria has been studied with various methods in several languages, questions remain concerning which features of the disorder are most consistent, which speaking tasks are most sensitive to the disorder, and whether the different speech production subsystems are uniformly affected. Perceptual and acoustic data were obtained from 14 individuals (seven men, seven women) with ataxic dysarthria for several speaking tasks, including sustained vowel phonation, syllable repetition, sentence recitation, and conversation. Multidimensional acoustic analyses of sustained vowel phonation showed that the largest and most frequent abnormality for both men and women was a long-term variability of fundamental frequency. Other measures with a high frequency of abnormality were shimmer and peak amplitude variation (for both sexes) and jitter (for women). Syllable alternating motion rate (AMR) was typically slow and irregular in its temporal pattern. In addition, the energy maxima and minima often were highly variable across repeated syllables, and this variability is thought to reflect poorly coordinated respiratory function and inadequate articulatory/voicing control. Syllable rates tended to be slower for sentence recitation and conversation than for AMR, but the three rates were highly similar. Formant-frequency ranges during sentence production were essentially normal, showing that articulatory hypometria is not a pervasive problem. Conversational samples varied considerably across subjects in intelligibility and number of words/ morphemes in a breath group. Qualitative analyses of unintelligible episodes in conversation showed that these samples generally had a fairly well-defined syllable pattern but subjects differed in the degree to which the acoustic contrasts typical of consonant and vowel sequences were maintained. For some individuals, an intelligibility deficit occurred in the face of highly distinctive (and contrastive) acoustic patterns.

Abstract Background: The Prostate Cancer Prevention Trial (PCPT) was a 7-year randomized, double-blind, placebo-controlled trial of the efficacy of finasteride for the prevention of prostate cancer with a primary outcome of histologically determined prevalence of prostate cancer at the end of 7 years. Methods: A systematic modeling process using logistic regression identified factors available at year 6 that are associated with end-of-study (EOS) biopsy adherence at year 7, stratified by whether participants were ever prompted for a prostate biopsy by year 6. Final models were evaluated for discrimination. At year 6, 13,590 men were available for analysis. Results: Participants were more likely to have the EOS biopsy if they were adherent to study visit schedules and procedures and/or were in good health (P < 0.01). Participants at larger sites and/or sites that received retention and adherence grants were also more likely to have the EOS biopsy (P < 0.05). Conclusions: Our results show good adherence to study requirements 1 year before the EOS biopsy was associated with greater odds that a participant would comply with the invasive EOS requirement. Impact: Monitoring adherence behaviors may identify participants at risk of nonadherence to more demanding study end points. Such information could help frame adherence intervention strategies in future trials. Cancer Epidemiol Biomarkers Prev; 23(8); 1638–48. ©2014 AACR.