Citations

Abstract Abstract #5110 Background: It has been demonstrated that certain chemotherapeutic drugs such as taxanes increases cyclooxygenase-2 (COX-2) levels. Upregulation of COX-2 may be a resistance mechanism of the tumor, or a method to modulate toxic effects of the agent. COX-2 is associated with less differentiated and more aggressive breast cancers, and the expression may be a prognostic indicator of disease. Studies defining the “true” impact of therapy on COX-2 activity are lacking. Hypothesis: Chemotherapy increases COX-2 function in patients with invasive breast cancer. This leads to increased PGE2, VEGF, and downregulation of immune responses. Objective: Patients with stage II or III breast cancer were enrolled in a phase II preoperative chemotherapy trial of docetaxel and carboplatin administered every two weeks (4 cycles). We evaluated circulating PGE2, VEGF, and immune cell phenotype at diagnosis and after chemotherapy. Results: Fifty seven patients were enrolled in the study and 32 were analyzed in the lab, most of them being infiltrating ductal carcinoma. Four had complete response, 20 had partial response, and 8 were non-responders. Due to low numbers of patients analyzed, statistical significance was not achieved in most instances. Nevertheless, intriguing data has been generated that warrants further investigation. VEGF/PGE2 versus clinical response to chemotherapy: 86% of the patients in whom VEGF levels decrease post chemotherapy were responders compared to 60% in which VEGF remained unchanged or increased slightly. Responders had decreased VEGF levels on average, while the non-responders increased. Interestingly, even with low sample size, if both VEGF and PGE2 levels increase post treatment the response rate to chemotherapy is significantly lower (55% versus 88% if both VEGF and PGE2 decrease post treatment, p=0.05). Thus, both VEGF and PGE2 are critical factors in determining response rate. Whether COX-2 activity is driving both factors or whether VEGF is independently regulated is yet to be determined. Clinical Response versus Dendritic cell (DCs) / T-cell data: Data revealed highly important trends that warrant future investigation. Patients with increased B7H4 (an immunosuppressive molecule expressed on tolerizing DCs) were non-responders while patients with decreased B7H4 were responders. In contrast, responders had increased levels of CD80 and CD86 (co-stimulatory molecules expressed on activating DCs). VEGF/PGE2 Change versus Dendritic/T-cell data: When VEGF increased post treatment, B7H4 and FoxP3 (T regulatory cells) increased, while CD80, CD86, and CD8 decreased. The association between VEGF and immune cells post chemotherapy treatment is the first indication that VEGF may regulate immune cell function possibly independent of COX-2 activity. These data suggest that anti-VEGF therapy (which may include COX-2 inhibitor) may not only augment responses to chemotherapy but may also augment immune responses post chemotherapy. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 5110.

Abstract Abstract #3057 Introduction: Patients (pts) with ER/PR/HER2 negative advanced breast cancer (triple negative, TN, basal-like) have limited treatment options and a poor prognosis. Ixabepilone (ixa), the first in a new class of antineoplastic agents, showed clinical benefit in combination with capecitabine (C) in 2 large clinical trials in metastatic breast cancer (MBC) pts either resistant to (study 046; JCO, 2007) or pretreated with anthracycline (A) and taxanes (T) (study 048). In 048, ixa + C, compared to C alone, demonstrated significant increases in PFS (HR 0.79 [0.69-0.90]) and ORR (43 vs. 29%). A trend towards increased OS was seen in both 048 (HR 0.90 [0.78-1.03]) and 046 (HR 0.90 [0.77-1.05]), which did not reach statistical significance. Here we present a pooled analysis of efficacy endpoints (ORR, PFS and OS) in pts with TN disease from these 2 phase III studies.
 Methods: 1973 pts with MBC previously treated with A and T were randomized in 2 phase III trials (046 and 048) to receive either ixa (40 mg/m2 IV over 3h Q3w) + C (1000 mg/m2 PO BID x14d Q3w) or C alone (1250 mg/m2 PO BID x14d Q3w). Due to the similarity of the study populations, individual pt data from both studies was pooled to better evaluate treatment effect within pre-planned patient subgroups.
 Results: 443 pts had TN disease in the two studies combined. ORR and PFS were superior in pts receiving combination therapy compared to those on C alone with a trend towards improved survival that did not reach statistical significance.
 
 Conclusions: Ixa + C is the first combination to show statistically significant PFS benefit in pts with advanced TN breast cancer from a pooled analysis of 2 phase III trials. Clinical benefit was consistently seen pts with TN disease in the individual studies as well. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 3057.

Abstract Abstract #2131 Introduction: TAS-108 is an oral steroidal anti-estrogen agent that selectively inhibits ERα and is mainly metabolized by CYP3A4. The purpose of this study is to investigate the efficacy and safety of TAS-108 administrated orally in three dose levels in patients with locally advanced, locally recurrent inoperable or metastatic breast carcinoma (BC) in four countries (USA, Russia, Mexico and Chile).
 Methods: Postmenopausal women with confirmed ER and/or PgR positive BC who had previously responded to one or two standard endocrine therapies, with or without one prior chemotherapy were randomly assigned to three doses of TAS-108, 40 mg, 80 and 120 mg daily. Using a modified Panageas' optimal two-stage trinomial design, the enrollment of 60 evaluable patients (first-stage: 19) was required to each individual dose group. Tumor response was assessed every 8 weeks according to RECIST criteria. Adverse events (AEs) were graded by CTC-AE v3.0.
 Results: A total of 146 patients with mean age of 63 years old were enrolled with 61 patients in the 40 mg group and 66 in the 80 mg group. The 120 mg group was terminated at the end of stage 1 with 19 patients enrolled due to lack of efficacy. The mean duration of study treatment was 172 days for the 40 mg group and 160 days for the 80 mg group. Partial response (PR) was documented in 6 (10%) patients in the 40 mg group and 4 (6.7%) patients in the 80 mg group. The rate of disease stabilization (CR+PR+SD) reported by the investigators was 43% (95%CI, 31%,56%) in the 40 mg group and 45% (95%CI, 32%,58%) in the 80 mg group. Adjudicated clinical benefit (CR+PR+SD more than 24 wks) was observed in 22% of patients in the 40 mg group and 20% of patients in the 80 mg group. Clinical benefit was achieved in 25% of patients with 1 prior hormonal therapy and 15% of patients with more than one line of prior hormonal therapy. Median time to progression (TTP): 15 weeks for the 40 mg group and 15.9 weeks for the 80 mg group. Median duration of clinical benefit was 32 weeks in the 40 mg group and 64 weeks in the 80 mg group. In the 40/80/120 mg groups, the commonly reported treatment-related AEs included nausea (15%/11%/16%), fatigue (10%/11%/16%), headache (10%/6%/16%), hot flushes (10%/5%/32%), diarrhea (2%/6%/5%), constipation (3%/3%/5%), and arthralgia (2%/5%/11%). No endometrial cancer and treatment-related deaths occurred during the study.
 Conclusions: TAS-108 has demonstrated anti-tumor activity in this population and was generally well tolerated. The 40 mg dose was chosen as the recommended dose for future clinical evaluation in patients with advanced breast cancer. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2131.

Abstract Abstract #2109 Background: Despite the impressive results of the recently released trastuzumab adjuvant therapy trials, 15% of patients with HER2 overexpressing or amplified breast cancer developed tumor relapse at 4 years. Lapatinib is a small molecule reversible TKI that inhibits both ErbB1 and ErbB2. The current study was developed to assess the cardiac safety and feasibility of adding lapatinib to paclitaxel and trastuzumab following as part of adjuvant therapy.
 Methods: A single-arm phase II study of doxorubicin (A, 60 mg/m2 day 1) and cyclophosphamide (C, 600 mg/m2 day 1) [q2w or q3w for 4 cycles]; followed by paclitaxel (P, 80 mg/m2 days 1, 8, 15), trastuzumab (T, 4 mg/kg loading dose then 2 mg/kg days 1, 8, 15), and lapatinib (L, 1000 mg days 1-21) [12 weeks]; followed by T (6 mg/kg day 1) and L (1000 mg days 1-21) [40 weeks] was conducted. The primary endpoint was the incidence of congestive heart failure. The current unplanned safety analysis was undertaken due to the observance of a high rate of G3/4 diarrhea.
 Results: From April 2007 to June 2008, 98 pts were enrolled and initiated study treatment. Median age was 51 (range 32-72). Among 83 pts with adverse event (AE) data available, 50 (60%) pts have experienced a G3/4 non-hematologic AE. During post-AC treatment, among 53 pts with AE data available, 31 (58.5%) patients have experienced a G3/4 non-hematologic AE with 24 (45%) patients reporting G3/4 diarrhea. Median cycle of onset of G3/4 diarrhea was cycle 5 (first cycle of PTL) with 16 (64%) cases first reported during cycle 5 and 5 (20%) cases first reported during cycle 6. Among 57, 46, 38, and 32 pts receiving treatment with PTL during cycles 5-8, 65%, 57%, 61%, and 72% of patients received the full L dose, respectively. 31 patients have ended active treatment with 10 due to patient refusal and 8 due to adverse events.
 Conclusions: Preliminary data suggest that L given concurrently with P and T at a dose of 1000 mg per day induces an unacceptable rate of moderate to severe diarrhea. Careful monitoring of diarrhea as well as L dose reduction and initiation of loperamide at first occurrence of diarrhea are recommended. The dose of L when given concurrently with P and T has been amended to 750 mg per day in the current study and safety data for the 1000 mg and 750 mg per day cohorts will be presented. Implications for the ongoing ALTTO study will also be presented. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2109.

Abstract Long-term outcomes and hence the role of adjuvant therapy in patients with small (≤1 cm), node-negative breast cancer remain unclear. This study's objective was to evaluate whether human epidermal growth factor receptor (HER)-2 status is an independent, poor prognostic marker in patients with these tumors and to identify a subgroup of patients with these small tumors who might benefit from adjuvant systemic therapy. All patients with a diagnosis of a node-negative breast tumor measuring ≤1 cm and available HER-2 test results between January 1, 2001, and December 31, 2005, at the three Mayo Clinic sites were identified. Clinicopathologic data were compared in three groups: HER-2−, HER-2+, and triple-negative (TN) tumors. Of the 421 tumors identified, 364 (86.5%) were HER-2−, 28 (6.7%) were HER-2+, and 29 (6.9%) were TN. The median follow-up time was 1,015 days (range, 1–2,549 days). Groups were balanced in terms of patient age and tumor histology. Eleven patients with HER-2− tumors (3.0%), seven with HER-2+ tumors (25.0%), and eight with TN tumors (27.6%) received adjuvant chemotherapy. Follow-up data were available for 357, 28, and 28 patients in the three groups, respectively. Death rates in the three groups were 6.4% (23 of 357) (one recurrence-related death), 0% (0 of 28), and 7.1% (2 of 28) (one recurrence-related death), respectively. During follow-up, the tumor recurred in nine patients: four were HER-2− tumors (1.1%), two were HER-2+ tumors (7.1%), and three were TN tumors (10.7%). Patients with small, node-negative breast tumors have an excellent prognosis, but HER-2+ and TN tumors appear to have a higher recurrence rate, warranting consideration for broad use and optimization of systemic adjuvant treatments.

Endothelial tubulogenesis is a crucial step in the formation of functional blood vessels during angiogenesis and vasculogenesis. Here, we use in vivo imaging of living zebrafish embryos expressing fluorescent fusion proteins of β-Actin, α-Catenin, and the ERM family member Moesin1 (Moesin a), to define a novel cord hollowing process that occurs during the initial stages of tubulogenesis in intersegmental vessels (ISVs) in the embryo. We show that the primary lumen elongates along cell junctions between at least two endothelial cells during embryonic angiogenesis. Moesin1-EGFP is enriched around structures that resemble intracellular vacuoles, which fuse with the luminal membrane during expansion of the primary lumen. Analysis of silent heart mutant embryos shows that initial lumen formation in the ISVs is not dependent on blood flow; however, stabilization of a newly formed lumen is dependent upon blood flow. Zebrafish moesin1 knockdown and cell transplantation experiments demonstrate that Moesin1 is required in the endothelial cells of the ISVs for in vivo lumen formation. Our analyses suggest that Moesin1 contributes to the maintenance of apical/basal cell polarity of the ISVs as defined by adherens junctions. Knockdown of the adherens junction protein Ve-cadherin disrupts formation of the apical membrane and lumen in a cell-autonomous manner. We suggest that Ve-cadherin and Moesin1 function to establish and maintain apical/basal polarity during multicellular lumen formation in the ISVs.

Purpose We examined associations between tumor characteristics (human epidermal growth factor receptor 2 [HER2] protein expression, HER2 gene and chromosome 17 copy number, hormone receptor status) and disease-free survival (DFS) of patients in the N9831 adjuvant trastuzumab trial. Patients and Methods All patients (N = 1,888) underwent chemotherapy with doxorubicin and cyclophosphamide, followed by weekly paclitaxel with or without concurrent trastuzumab. HER2 status was determined by immunohistochemistry (IHC) and fluorescent in situ hybridization (FISH) at a central laboratory, Mayo Clinic, Rochester, MN. Patients with conflicting local positive HER2 expression results but normal central laboratory testing were included in the analyses (n = 103). Results Patients with HER2-positive tumors (IHC 3+, FISH HER2/centromere 17 ratio ≥ 2.0, or both) benefited from trastuzumab, with hazard ratios (HRs) of 0.46, 0.49, and 0.45, respectively (all P < .0001). Patients with HER2-amplified tumors with polysomic (p17) or normal (n17) chromosome 17 copy number also benefited from trastuzumab, with HRs of 0.52 and 0.37, respectively (P < .006). Patients who received chemotherapy alone and had HER2-amplified and p17 tumors had a longer DFS than those who had n17 (78% v 68%; P = .04), irrespective of hormone receptor status or tumor grade. Patients with HER2-normal tumors by central testing (n = 103) seemed to benefit from trastuzumab, but the difference was not statistically significant (HR, 0.51; P = .14). Patients with hormone receptor–positive or –negative tumors benefited from the addition of trastuzumab, with HRs of 0.42 (P = .005) and 0.60 (P = .0001), respectively. Conclusion These results confirm that IHC or FISH HER2 testing is appropriate for patient selection for adjuvant trastuzumab therapy. Trastuzumab benefit seemed independent of HER2/centromere 17 ratio and chromosome 17 copy number.

New research stratifies the origin of an inherited multisystem channelopathy, a finding that has implications for personalized diagnosis and therapy.

Abstract Genomic perturbations that challenge normal signaling at the pluripotent stage may trigger unforeseen ontogenic aberrancies. Anticipatory systems biology identification of transcriptome landscapes that underlie latent phenotypes would offer molecular diagnosis before the onset of symptoms. The purpose of this study was to assess the impact of calreticulin-deficient embryonic stem cell transcriptomes on molecular functions and physiological systems. Bioinformatic surveillance of calreticulin-null stem cells, a monogenic insult model, diagnosed a disruption in transcriptome dynamics, which re-prioritized essential cellular functions. Calreticulin-calibrated signaling axes were uncovered, and network-wide cartography of undifferentiated stem cell transcripts suggested cardiac manifestations. Calreticulin-deficient stem cell-derived cardiac cells verified disorganized sarcomerogenesis, mitochondrial paucity, and cytoarchitectural aberrations to validate calreticulin-dependent network forecasts. Furthermore, magnetic resonance imaging and histopathology detected a ventricular septal defect, revealing organogenic manifestation of calreticulin deletion. Thus, bioinformatic deciphering of a primordial calreticulin-deficient transcriptome decoded at the pluripotent stem cell stage a reconfigured multifunctional molecular registry to anticipate predifferentiation susceptibility toward abnormal cardiophenotype.

Purpose In March 1998, Common Toxicity Criteria (CTC) version 2.0 introduced the collection of attribution of adverse events (AEs) to study drug. We investigate whether attribution adds value to the interpretation of AE data. Patients and Methods Patients in the placebo arm of two phase III trials—North Central Cancer Treatment Group Trial 97-24-51 (carboxyamino-triazole v placebo in advanced non–small-cell lung cancer) and American College of Surgeons Oncology Group Trial Z9001 (imatinib mesylate v placebo after resection of primary gastrointestinal stromal tumors)—were studied. Attribution was categorized as unrelated (not related or unlikely) and related (possible, probable, or definite). Results In total, 398 patients (84 from Trial 97-24-51 and 314 from Trial Z9001) and 7,736 AEs were included; 47% and 50% of the placebo-arm AEs, respectively, were reported as related. When the same AE was reported in the same patient on multiple visits, the attribution category changed at least once 36% and 31% of the time. AE type and sex (Trial Z9001) and AE type and performance status (Trial 97-24-51) were associated with a higher likelihood of AEs being deemed related. Conclusion Nearly 50% of AEs were reported as attributed to study drug on the placebo arm of two randomized clinical trials. These data provide strong evidence that AE attribution is difficult to determine, unreliable, and of questionable value in interpreting AE data in randomized clinical trials.