Effect of zoledronic acid on disseminated tumour cells in women with locally advanced breast cancer: an open label, randomised, phase 2 trial.

BACKGROUND: Treatment with bisphosphonates decreases bone loss and can increase disease-free survival in patients with breast cancer. The aim of our study was to assess the effect of zoledronic acid on clearance of disseminated tumour cells (DTCs) from the bone marrow in women undergoing neoadjuvant chemotherapy for breast cancer. METHODS: Patients were recruited for this open-label, phase 2 randomised trial between March 17, 2003, and May 19, 2006, at a single centre. Eligible patients had clinical stage II-III (> or = T2 and/or > or = N1) newly diagnosed breast cancer, Eastern Cooperative Oncology Group performance status of 0 or 1, and normal cardiac, renal, and liver function. 120 women were randomly assigned, using allocation concealment, to receive 4 mg zoledronic acid intravenously every 3 weeks (n=60), or no zoledronic acid (n=60), for 1 year concomitant with four cycles of neoadjuvant epirubicin (75 mg/m(2)) plus docetaxel (75 mg/m(2)) and two cycles of adjuvant epirubicin plus docetaxel. The primary endpoint was the number of patients with detectable DTCs at 3 months. Final analysis was done 1 year after the last patient was enrolled. Analyses were done for all patients with available data at 3 months. This study is registered with ClinicalTrials.gov, number NCT00242203. FINDINGS: Of the 120 patients initially enrolled, one withdrew after signing consent and one patient's baseline bone marrow was not available. Both of these patients were in the control group. At 3 months, 109 bone-marrow samples were available for analysis. In the zoledronic acid group, bone marrow was not collected from one patient because of disease progression, one patient was taken off study because of severe diarrhoea, and two patients had not consented at the time of surgery. In the control group, bone marrow was not collected from two patients because of disease progression, one patient withdrew consent, and three patients were not consented at the time of surgery. At baseline, DTCs were detected in 26 of 60 patients in the zoledronic acid group and 28 of 58 patients in the control group. At 3 months, 17 of 56 patients receiving zoledronic acid versus 25 of 53 patients who did not receive zoledronic acid had detectable DTCs (p=0.054). The most common grade 3-4 toxicities were infection (five of 60 patients in the zoledronic acid group and six of 59 in the control group) and thrombosis (five of 60 in the zoledronic acid and two of 59 in the control group). There was one documented case of osteonecrosis in the zoledronic acid group. INTERPRETATION: Zoledronic acid administered with chemotherapy resulted in a decreased proportion of patients with DTCs detected in the bone marrow at the time of surgery. Our study supports the hypothesis that the antimetastatic effects of zoledronic acid may be through effects on DTCs. FUNDING: Novartis Pharmaceuticals and Pfizer Inc.

A gene expression signature that predicts the therapeutic response of the basal-like breast cancer to neoadjuvant chemotherapy.

Several gene expression profiles have been reported to predict breast cancer response to neoadjuvant chemotherapy. These studies often consider breast cancer as a homogeneous entity, although higher rates of pathologic complete response (pCR) are known to occur within the basal-like subclass. We postulated that profiles with higher predictive accuracy could be derived from a subset analysis of basal-like tumors in isolation. Using a previously described "intrinsic" signature to differentiate breast tumor subclasses, we identified 50 basal-like tumors from two independent clinical trials associated with gene expression profile data. 24 tumor data sets were derived from a 119-patient neoadjuvant trial at our institution and an additional 26 tumor data sets were identified from a published data set (Hess et al. J Clin Oncol 24:4236-4244, 2006). The combined 50 basal-like tumors were partitioned to form a 37 sample training set with 13 sequestered for validation. Clinical surveillance occurred for a mean of 26 months. We identified a 23-gene profile which predicted pCR in basal-like breast cancers with 92% predictive accuracy in the sequestered validation data set. Furthermore, distinct cluster of patients with high rates of cancer recurrence was observed based on cluster analysis with the 23-gene signature. Disease-free survival analysis of these three clusters revealed significantly reduced survival in the patients of this high recurrence cluster. We identified a 23-gene signature which predicts response of basal-like breast cancer to neoadjuvant chemotherapy as well as disease-free survival. This signature is independent of tissue collection method and chemotherapeutic regimen.

Ethanol differentially affects ATP-gated P2X(3) and P2X(4) receptor subtypes expressed in Xenopus oocytes.

P2X receptors are cation-selective, ligand-gated ion channels activated by synaptically released, extracellular adenosine 5'-triphosphate (ATP). ATP-gated currents are inhibited by ethanol when tested in dorsal root ganglion and CA1 neurons. Recently, we reported differences in sensitivity to ethanol inhibition between homomeric P2X(2) and P2X(4) receptors expressed in Xenopus oocytes, which suggested that subunit composition of native P2X receptors determines their ethanol sensitivity. The present study extended the investigation to P2X(3) receptors. The effects of ethanol and zinc ions (Zn(2+)) were tested on homomeric P2X(3) and P2X(4) receptors expressed in Xenopus oocytes using two-electrode voltage clamp. Ethanol potentiated ATP-gated P2X(3) receptor currents in a concentration dependent manner. In contrast, ethanol inhibited P2X(4) receptor function. Ethanol did not directly alter receptor function, nor did it alter the Hill coefficient or maximal ATP response (E(max)) in either P2X(3) or P2X(4) receptors. Ethanol increased the maximal response to Zn(2+) ATP-gated currents in P2X3 receptors which suggests that ethanol and Zn(2+) act on different sites. The differences in ethanol response of P2X(3) and P2X(4) receptors set the stage for future investigations that will use chimeric P2X receptors or other molecular manipulations of P2X structure to investigate the molecular sites and mechanisms of action of ethanol.

Effects of ethanol on adenosine 5'-triphosphate-gated purinergic and 5-hydroxytryptamine receptors.

This report of the proceedings of a symposium presented at the 2005 annual meeting of the Research Society on Alcoholism highlights the actions of ethanol on purinergic (P2XRs) and 5-hydroxytryptamine3 (5-HT3Rs) receptors. Both P2XRs and 5-HT3Rs, are modulated by pharmacologically relevant concentrations of ethanol, with inhibition or stimulation of P2XR subtypes and stimulation of 5-HT3Rs, respectively. With regard to ethanol-modulatory actions, these 2 distinctly different receptor classes have been studied to a much lesser extent than other LGICs. The organizers and chairs were Daryl L. Davies and Tina K. Machu. John J. Woodward discusses the molecular pharmacology and physiology of P2XRs and 5-HT3Rs and sets the stage for a detailed investigation into the ethanol sensitivity of these channels by the invited speakers. Daryl L. Davies discusses the results from recent electrophysiological studies conducted in his and Dr. Woodward's laboratories, highlighting the actions of ethanol on P2XR subtypes. Jiang-Hong Ye discusses results from recent studies using loose-patch and whole-cell recordings on purinergic receptors expressed on neurons from the ventral tegmental area (VTA) in rats. Tina K. Machu discusses electrophysiological studies conducted in her and Dr. David Lovinger's laboratories on nonpore lining residues of the second transmembrane domain (TM2) of the 5-HT3A receptor. Li Zhang presents data demonstrating that F-actin cytoskeletons play a critical role in 5-HT3 receptor clustering in hippocampal neurons. Collectively, the presentations provided strong evidence that P2X and 5-HT3 receptors are important targets for ethanol action.