Three of the studies described in this section relate to bladder cancer. The first of these concerns the PI‐3 kinase pathway, which has been a topic of interest in cancer in general. The authors from Sacramento suggest that it may regulate cancer cell invasion, and hope that this may lead to translational therapeutic uses.Another study describes the pharmacological characteristics of Ro115‐1240, which is a selective alpha1A/1L adrenoceptor partial agonist, a compound which may have a future in treating stress urinary incontinence.OBJECTIVESTo investigate the role of the phosphatidylinositol (PI)‐3 kinase pathway in the invasion of bladder cancer cell lines, and to assess the activation of this pathway in primary human bladder tumours.MATERIALS AND METHODSHuman bladder cancer cells were treated with pathway specific inhibitors or were transfected with PI‐3 kinase pathway components. The invasion of cultured bladder cancer cells was analysed by an invasion assay. Bladder cancer cells lines and primary human bladder tumours were analysed for pathway activation by western blotting.RESULTSA specific inhibitor of PI‐3 kinase enzyme activity, Ly294002, potently suppressed the invasive properties of three highly invasive bladder tumour cell lines. Restoration of the PTEN gene to invasive UM‐UC‐3 bladder tumour cells or expression of a dominant‐negative version of the PI‐3 kinase target, Akt, also potently inhibited invasion, indicating a central role for the PI‐3 kinase/Akt pathway in this process. In addition, 55% of primary tumours from patients with bladder cancer had markedly high levels of phosphorylated Akt.CONCLUSIONPharmacological or biochemical inhibition of the PI‐3 kinase pathway drastically reduced the invasive capacity of bladder cancer cell lines; over half of primary human bladder tumours had high Akt phosphorylation, suggesting that the aberrant activation of this pathway may contribute to the invasion of a significant subset of bladder cancers.

Introduction: Patients with triple negative breast cancer (TNBC) have a worse prognosis compared to other breast cancer subtypes, primarily due to lack of targeted treatment options. EGFR1 (epidermal growth factor receptor) is often over-expressed in TNBC and could be a promising therapeutic target. Clinical studies have shown platinums and taxanes to be effective in TNBC and in vitro data has demonstrated synergy between carboplatin, docetaxel and an EGFR inhibitor in TNBC cell lines. Aim: To evaluate the efficacy of platinum/taxane based chemotherapy in combination with a small molecule EGFR inhibitor, Erlotinib, in patients with TNBC. Methods: Patients with stage II/III TNBC were eligible for this phase II trial. All patients received 6 cycles of chemotherapy (Carboplatin AUC 6, Docetaxel 75mg/m2 every 21 d). In addition patients were equally randomized between two erlotinib arms. Patients in arm A received Erlotinib (150 mg PO d 3 - 14 every 21 d) during all 6 cycles of chemotherapy & patients in arm B received erlotinib only during the last 4 cycles of chemotherapy. This randomization was intended to reduce bias in the evaluation of the effect of erlotinib on biomarkers in a core biopsy of the tumor performed after the second cycle of chemotherapy. All but one patient underwent comprehensive BRCA analysis (Myriad Genetic Laboratories). Following neo-adjuvant therapy, all patients underwent breast surgery. The primary end point was pathological complete response (pCR: no evidence of invasive tumor in the breast & axilla). Minimal Residual Disease [MRD= Residual Cancer Burden (RCB) groups 0+1] status was also evaluated. Results: 30 eligible patients with TNBC were enrolled between 8/2007 and 6/2010. This analysis includes 28 patients since 2 patients are still on study treatment. Median age: 51yrs (range 31-68), 21%: African American, 54%: postmenopausal. Median tumor size was 3.3 cm & 39% had LN+ disease. Fifteen patients were assigned to each arm of erlotinib. Five of 28 patients (17%) carried a BRCA mutation (two BRCA1deleterious, two BRCA2 deleterious, one BRCA1 uncertain). The overall pCR and MRD (RCB 0+1) rates were 39% & 50% respectively. On univariate analysis, tumor size, LN status, menopausal status, age and number of erlotinib cycles did not correlate with pCR. However, BRCA mutation status strongly correlated with pCR, with a pCR rate of 100% in BRCA mutation carriers compared to 27% in those without BRCA mutation (p=0.006). Baseline EGFR and/or p53 expression of ≥10% was associated with a lower pCR rate in BRCA non-carriers (pCR: 12% vs. 66%, p = 0.025). Common Erlotinib related AEs were: rash (G3/4:7%) & diarrhea (G3/4:30%) with 32% of subjects requiring erlotinib dose reduction/discontinuation due to AEs. Conclusions: Pathological complete response rates of TNBC to a combination of platinum/taxane chemotherapy & an oral EGFR inhibitor are encouraging and should be explored further. The response to this regimen was significantly influenced by BRCA mutation status, indicating a need to stratify patients by their BRCA status in future TNBC trials. Tissue biomarker analysis of downstream targets of EGFR inhibition should be informative regarding the exact role of erlotinib in this patient population. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-11-07.

Introduction: Triple negative breast cancer (TNBC) and BRCA1-associated breast cancers share many histopathologic and molecular features. BRCA1 plays a crucial role in HR-dependent DNA repair and BRCA1-deficient cells are particularly susceptible to the DNA damaging agents like platinums. Increasing evidence suggests that in addition to germline BRCA defects, other mechanisms (like epigenetic BRCA1 silencing) can lead to BRCA1 insufficiency in TNBC. However, the impact of BRCA1 insufficiency on the efficacy of DNA damaging agents in TNBC is not known. Aim: To investigate the impact of BRCA1 insufficiency on relapse-free survival (RFS) and overall survival (OS) in patients with stage II-III TNBC treated with neoadjuvant platinum-based chemotherapy. BRCA1 insufficiency (BRCA1insuf) state was defined as presence of germline BRCA1/2 mutation or BRCA1 promoter methylation (PM) and/or low BRCA1 expression (lowest quartile). Methods: Thirty patients with stage II/III TNBC received neoadjuvant chemotherapy (6 cycles of Carboplatin AUC 6, Docetaxel 75mg/m2 and Erlotinib 150 mg PO) on a phase II trial between 8/2007–6/2010. All but one patient underwent comprehensive BRCA analysis (Myriad Genetic Laboratories). Pre-treatment tumor specimens were used for evaluation of BRCA1 PM and expression. Genomic DNA was isolated from FFPE samples, bisulfite converted and then subjected to methylation-specific PCR (MSP). RNA was isolated, reverse transcribed to cDNA and assayed by quantitative real-time PCR (qRT-PCR) for determination of BRCA1 mRNA transcript levels. RFS and OS were estimated according to the Kaplan-Meier method and compared among groups with log-rank statistic. Cox proportional hazards models were fit to determine the association of BRCA1insuf with the risk of death after adjustment for other characteristics. Results: Median age: 51yrs, African American: 20%, Median tumor size: 3.3 cm, LN positive: 40%. Six of 30 patients (20%) harbored germline BRCA mutation (4 BRCA1, 2 BRCA2). Baseline tumor specimen was available for 26/30 patients. BRCA1 MSP was successful in 92% and BRCA1 qRT-PCR was successful in 84% of specimens. BRCA1 PM and low BRCA1 expression was present in 30% and 15% of subjects, respectively. There was evidence of BRCA1insuf in 53% (16/30) of subjects. At a median time from diagnosis of 42 months (range, 23–59 months) there have been 9(30%) recurrences and 7(23%) deaths. On univariate analysis node negativity, lower stage and presence of BRCA1insuf were associated with better OS. At the median follow up, RFS is 81% for patients with BRCA1insuf versus 54% for patients without BRCA1insuf (p = 0.16); OS is 83% for patients with BRCA1insuf versus 46% for patients without BRCA1insuf (p = 0.021). After adjustment for clinical variables patients with BRCA1insuf had a significantly better OS compared to patients without BRCA1insuf (p = 0.036). Conclusions: Germline BRCA testing plus tissue BRCA1 PM/expression can be used to identify a BRCA1insuf sub-population within TNBC demonstrating a favorable outcome with platinum treatment. This BRCA1insuf criteria can be easily used to select TNBC patients likely to benefit from DNA damaging agents like platinums and PARP inhibitors. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr PD09-02.

Background: In early ER+ breast cancer, neo-adjuvant (NA) endocrine therapy (ET) may identify a subset of patients with endocrine sensitive disease with excellent outcomes without chemotherapy. In patients receiving a NA aromatase inhibitor, on- therapy, short term (day 14) Ki-67 of <10% and post NA pre-operative endocrine prognostic index (PEPI) 0 at surgery are associated with low relapse rates without chemotherapy. Ribociclib, a novel CDK4/6 inhibitor is active in ER+ metastatic breast cancer. We hypothesize that ribociclib+letrozole as NA ET for stage II-III breast cancer will increase the number of women with a PEPI 0 at surgery. Trial Design: Randomized, placebo-controlled, multi-center, phase II, investigator initiated trial of NA letrozole +/- ribociclib in postmenopausal women with ER+, HER2-, breast cancer. Subjects will be randomized 1:1:1 to letrozole 2.5 mg daily + placebo, letrozole 2.5mg daily + ribociclib 600mg daily on D1-21 of a 28 day cycle (intermittent dosing), or letrozole 2.5mg daily + ribociclib 400mg daily (continuous dosing). Treatment will be continued for 6 months followed by surgery. Research core biopsies and blood will be collected at baseline, at day 14, and at surgery. A Ki67 >10% at day 14 will result in discontinuation of the subject from the protocol as this may be an early indicator of resistance to endocrine therapy. An MRI will be done after 2 months of therapy to assess response/progression. Primary endpoint is a PEPI score of 0 at surgery. Key Eligibility Criteria: Postmenopausal (natural or surgical) women with stage II/III ER+, HER2- breast cancer. Must have a palpable breast mass of at least 2 cm. Multicentric/contralateral invasive disease not allowed. Ipsilateral/contralateral DCIS is allowed. Inflammatory breast cancer is excluded. Specific Aims: Primary objective: To determine if ribociclib+letrozole as a 24 week NA ET increases rate of PEPI score of 0 at surgery compared to letrozole. Secondary objectives: To determine if ribociclib+letrozole as a 24 week NA ET increases the proportion of tumors with complete cell cycle arrest compared to letrozole; to determine if ribociclib in combination with letrozole for 24 weeks results in improved 5 year RFS compared to letrozole; to examine differences in response rates between the two ribociclib containing arms vs letrozole. Statistical Methods: The two ribocilib containing arms (n=80) will be combined for analysis against placebo + letrozole (n=40). Assuming that addition of ribociclib will increase the rate of PEPI 0 by 20%, and setting Type I error rate at 10% and Type II error rates at 20% in the final analysis, a sample size of 80 women in the treatment arms (40 in each arm) and 40 women in the control arm are needed to show significance. Patient accrual and target accrual: Participating sites include The Univ of Kansas Med Ctr, City of Hope National Med Ctr, Massachusetts General Hospital, University of Miami Sylvester Comprehensive Cancer Ctr, University of Arkansas for Medical Sciences, and University of Wisconsin. The trial has accrued 16 patients with a target accrual of 120 patients. Accrual should be complete in 2/2017. Contact information: Qamar Khan, MD (qkhan@kumc.edu). Citation Format: Khan QJ, Prochaska LH, Mohammad J, Yuan Y, O'Dea A, Bardia A, Wisinski K, Hard M, Baccaray S, Makhoul I, Wagner J, Laura S, Ma C, Sharma P. Femara plus ribociclib or placebo as neo-adjuvant endocrine therapy for women with ER+, HER2-negative early breast cancer - The Feline trial [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 OT3-02-06.

Introduction Mutations/deregulations in the phosphatidylinositol-3-kinase (PI3K) pathway are common in breast cancer, Inhibition of the PI3K pathway is recognized as a promising target for the treatment of breast cancer. Although taxanes are effective early on in advanced stage breast cancer, resistance often develops. It has been demonstrated that activation of the PI3K/AKT pathway confers resistance to paclitaxel, and in preclinical models, concomitant inhibition of the PI3K pathway enhances the efficacy of taxanes. BYL719 is a potent oral, class I PI3K inhibitor which strongly inhibits the PI3K alpha isoforms and is significantly less active against the other class I isoforms. Targeting the alpha isoform of PI3K is expected to improve the therapeutic window over inhibitors with less isoform specificity. Nab-Paclitaxel is a solvent-free, nanoparticle, albumin-based paclitaxel which takes advantage of the antitumor activity of paclitaxel while decreasing the toxicities typically associated with the solvent (Cremophor) used to administer the most common formulation of paclitaxel. Methods A 3+3 dose-escalation design evaluated three dose levels of BYL719 (250mg, 300mg, and 350mg) administered PO once daily (D1-28) with nab-Paclitaxel (100 mg/m2 intravenously D 1, 8, 15) every 28 days in patients with metastatic HER 2 negative breast cancer. The aims of the study were to 1) determine the recommended phase II dose (RPTD) of BYL719 + nab-Paclitaxel, 2) assess pharmacokinetics of BYL and nab-paclitaxel, and 3) assess preliminary efficacy. Results 10 patients were enrolled at 3 dose levels of BYL719 and 3 patients were enrolled in expansion cohort at the RPTD of BYL719 of 350 mg PO daily plus nab-paclitaxel 100mg/m2 (D 1, 8, 15). Median age was 61years; 54% (7/13) of patients were hormone receptor positive and 46% (6/13) triple negative. 85% (11/13) had visceral disease, 69% (9/13) had received prior chemotherapy for metastatic disease and 85% (11/13) had received prior taxane in adjuvant/metastatic setting. There were no DLTs in the three cohorts and the MTD of BYL was not reached. Hyperglycemia (G3:31%, G4:0%) and neutropenia (G3:15%, G4:8%), were the most common grade 3/4 adverse events. There were no Grade 3/4 diarrhea or rash. Best overall response for 12 patients was 58% (7/12) (complete response=1, partial response=6), and an additional 33% (4/12) demonstrated stable disease. Objective responses were noted in both hormone positive and triple negative disease. Median duration of response is 6.5 months (range 2-14 months). No pharmacokinetic interactions were detected when BYL and nab-paclitaxel were co-administered. Discussion: This phase I study demonstrates that combination of BYL719 and nab-paclitaxel was well tolerated and shows encouraging efficacy in metastatic HER2 negative breast cancer. Enrollment in the phase II portion of the trial at the RPTD (BYL719 350mg PO daily plus nab-paclitaxel 100mg/m2 D1,8,15 every 28 days) continues. Ongoing analysis of PI3K pathway alterations in tumor and cfDNA will be correlated with clinical response. Citation Format: Sharma P, Abramson VG, O'Dea A, Lewis S, Scott JN, Ward J, De Jong JA, Lehn C, Brown AR, Williamson SK, Perez RP, Komiya T, Godwin AK, Reed GA, Khan QJ. Safety and efficacy results from phase I study of BYL 719 plus nab-paclitaxel in HER 2 negative metastatic 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 P6-11-08.