Efficacy of BSI-201, a poly (ADP-ribose) polymerase-1 (PARP1) inhibitor, in combination with gemcitabine/carboplatin (G/C) in patients with metastatic triple-negative breast cancer (TNBC): Results of a randomized phase II trial

3

Background: TNBC is an aggressive breast cancer subtype that shares molecular and pathologic features with BRCA1-related breast cancers. BRCA-deficient cells are sensitive to inhibition of PARP1, a critical enzyme of cell proliferation and DNA repair, and thus represent a rational target of PARP inhibitor-based cancer therapy. The objectives of this study were to evaluate BSI-201, a potent PARP1 inhibitor, in combination with gemcitabine/carboplatin (G/C) in subjects with metastatic TNBC. Methods: Eligible subjects had measurable disease and had ≤2 prior cytotoxic regimens for ER-, PR-, and HER2-negative metastatic breast cancer. Patients were randomized (1:1) to G/C alone or G/C + BSI-201. Gemcitabine (1000 mg/m2) and carboplatin (AUC=2) were given on days 1 and 8, and BSI-201 (5.6 mg/kg; iv; biweekly) on days 1, 4, 8, and 11 every 21 days. Endpoints were clinical benefit rate (CBR = CR + PR + SD ≥6 months), progression-free survival (PFS) and overall survival (OS). Results: Analyses of the first 86 of a planned 120 patients showed that BSI-201 + G/C had improved CBR, median PFS, and median OS, compared with G/C alone. The frequency and nature of adverse events (AEs) did not differ between arms. Conclusions: This preliminary analysis demonstrates that BSI-201 + G/C significantly improves CBR, PFS, and OS, compared with G/C alone. BSI-201 + G/C was well tolerated, with BSI-201 adding no significant toxicity to G/C. Updated CBR, PFS, and OS for all 120 patients and exploratory correlative analyses of PARP expression and clinical response will be presented.

[Table: see text] [Table: see text]

Efficacy of BSI-201, a poly (ADP-ribose) polymerase-1 (PARP1) inhibitor, in combination with gemcitabine/carboplatin (G/C) in patients with metastatic triple-negative breast cancer (TNBC): Results of a randomized phase II trial

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The full, final text of this abstract will be available in Part II of the 2009 ASCO Annual Meeting Proceedings, distributed onsite at the Meeting on May 30, 2009, and as a supplement to the June 20, 2009, issue of the Journal of Clinical Oncology.

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Immunological and genetic analysis of 65 patients with a clinical suspicion of X linked hyper-IgM

BACKGROUND

X linked hyper-IgM (XHIM) is a primary immunodeficiency caused by mutations in the tumour necrosis factor superfamily 5 gene, TNFSF5, also known as the CD40 ligand (CD40L) gene. Patients often present with recurrent infections, and confirmation of a diagnosis of XHIM enables appropriate therapeutic interventions, including replacement immunoglobulin, antibiotics, and bone marrow transplantation.

AIM

To review and optimise the institution's diagnostic strategy for XHIM.

METHOD

Samples from 65 boys were referred to this centre for further investigation of suspected XHIM. The results, which included a flow cytometric whole blood assay for CD40L expression followed by mutation analysis in selected patients, were reviewed.

RESULTS

Twenty one patients failed to express CD40L and TNFSF5 mutations were found in 20 of these patients. In contrast, no TNFSF5 mutations were found in 16 patients with weak expression of CD40L. Interestingly, one quarter of patients with confirmed XHIM who had TNFSF5 mutations had low concentrations of IgG, IgA, and IgM. Most of the remaining patients with XHIM had the classic pattern of normal or raised IgM with low concentrations of IgA and IgG.

CONCLUSIONS

This study demonstrates the usefulness of the whole blood staining method as a rapid screen to select patients for subsequent TNFSF5 mutation analysis, and shows the benefits of a unified protein/genetic diagnostic strategy.

Drug-mediated toxicity caused by genetic deficiency of UDP-glucuronosyltransferases

Human gene families encoding UDP-Glucuronosyltransferases (UGTs) have been identified and partially characterised. This family of enzymes catalysed the glucuronidation of drugs, xenobiotics and endobiotics. Genetic mutations and polymorphisms have been identified in several UGT genes and examples should be anticipated in all UGT genes. A common genetic defect in the TATA box promoter of the UGT1A1 gene is associated with Gilbert's Syndrome (GS) causing mild hyperbilirubinaemia. Recently, adverse effects of anticancer agents have been observed in Gilbert's patients due to reduced drug or bilirubin glucuronidation.

Gilbert's syndrome is a contributory factor in prolonged unconjugated hyperbilirubinemia of the newborn

OBJECTIVE

Prolonged neonatal jaundice, beyond day 14 of life, is very common and of concern to the clinician. The aim of this study was to investigate whether a genetic mutation in the bilirubin UGT1A1 gene, which has been associated with Gilbert's syndrome in adults, is a contributory factor in prolonged neonatal jaundice.

STUDY DESIGN

Blood was collected from 85 term newborns with unexplained hyperbilirubinemia, and DNA was prepared. The neonates were divided into 6 groups depending on whether they were breast-fed or bottle-fed and whether they had acute, prolonged, or very prolonged jaundice. UGT1A1 TATA promoter genotyping (DNA test for Gilbert's syndrome) was performed on all samples, and analysis of the entire UGT1A1 coding sequence was performed in a representative sample (11 of 26) of very prolonged cases.

RESULTS

In addition to the known common UGT1A1 TATA alleles (TA6 and TA7), a novel TATA allele (TA5) in a neonate with very prolonged jaundice was identified. Statistical analysis of the TATA genotype distributions within the group of breast-fed neonates revealed significant differences among the acute, prolonged, and very prolonged subgroups (.05 > P >.01): the incidence of familial hyperbilirubinemia genotypes (7/7 and 5/7) is 5 times greater in very prolonged cases (31%) relative to acute cases (6%). Neonates with prolonged jaundice from family pedigrees were observed to demonstrate the Gilbert's phenotype as children or young adults.

CONCLUSIONS

A genetic predisposition to develop prolonged neonatal hyperbilirubinemia in breast-fed infants is associated with TATA box polymorphism of the UGT1A1 gene and will be recognized as Gilbert's syndrome in adulthood.

Genetic defects of the UDP-glucuronosyltransferase-1 (UGT1) gene that cause familial non-haemolytic unconjugated hyperbilirubinaemias

Congenital familial non-haemolytic hyperbilirubinaemias are potentially lethal syndromes caused by genetic lesions that reduce or abolish hepatic bilirubin UDP-glucuronosyltransferase activity. Here we describe genetic defects that occur in the UGT1 gene complex that cause three non-haemolytic unconjugated hyperbilirubinaemia syndromes. The most severe syndrome, termed Crigler-Najjar syndrome type I, is mainly associated with mutations in exons 2 to 5 that affect all UGT1 enzymes and many of the mutations result in termination codons and frameshifts. Crigler-Najjar type II syndrome which is treatable with phenobarbital therapy is associated with less dramatic missense mutations or heterozygous expression of mutant and normal alleles. Gilbert's syndrome, the most prevalent (2-19% in population studies) and mildest of the three syndromes is principally caused by a TA insertion at the TATA promoter region upstream of the UGT1A1 exon. Current methods used for the diagnosis and treatment of these diseases are discussed.

Genetic variation in bilirubin UPD-glucuronosyltransferase gene promoter and Gilbert's syndrome

BACKGROUND

The genetic basis of Gilbert's syndrome is ill-defined. This common mild hyperbilirubinaemia sometimes presents as an intermittent jaundice. A reduced hepatic bilirubin UPD- glucuronosyltransferase (UGT) is associated with this syndrome. We have examined variation in the gene encoding the UGT1*1 enzyme and serum bilirubin levels in a Scottish population.

METHODS

Blood was collected from 12 patients with confirmed or suspected Gilbert's syndrome, from 6 members of a family with 4 Gilbert members, and from 77 non-smoking, alcohol-free, drug-free volunteers recruited from the staff of a teaching hospital in Dundee. Polymerase chain reaction amplification was used to examine sequence variation of the promoter upstream of the UGT1*1 exon I. Genotypes were assigned as follows: 6/6 (homozygous for a common allele bearing the sequence [TA](6)TAA), 7/7 (homozygous for a rarer allele with the sequence [TA](7)TAA), and 6/7 (heterozygous with one of each allele).

FINDINGS

Individuals in the population with the 7/7 genotype had significantly higher bilirubin concentrations than those who had the 6/7 or 6/6 genotype. 14 volunteers underwent a 24 h fasting test to see if they had Gilbert's syndrome, and all four positives had the 7/7 genotype. One confirmed Gilbert's patient, two recurrent jaundice patients (with suspected Gilbert's syndrome), and nine clinically diagnosed cases had the 7/7 genotype. Segregation of the 7/7 genotype with the Gilbert phenotype was also demonstrated in the family with four affected members. The frequency of the 7/7 genotype in this eastern Scottish population was 10-13%.

INTERPRETATION

In a healthy population there was an association between variation in bilirubin concentration and a mutation within the gene encoding the enzyme bilirubin UGT. This and other findings suggest the existence of a mild and a more severe form of Gilbert's syndrome, depending on whether the gene defect lies in the promoter sequence upstream of UGT1*I exon I, as here (mild), or in the coding sequence (severe) of the gene.

Endoluminal repair of atypical dissecting aneurysm of descending thoracic aorta and fusiform aneurysm of the abdominal aorta

A 62-year-old male patient was admitted with acute dissociation of the descending thoracic aorta and an infrarenal abdominal aortic aneurysm (AAA). Investigation revealed that the thoracic dissection probably had arisen retrogradely in the posterior wall of the AAA and extended superiorly to the left subclavian artery as a blind sac. Implantation of an endoluminal graft device below the renal arteries enabled simultaneous treatment of the AAA and the thoracic aortic dissection. The patient had an uncomplicated recovery. Postoperative aortography and computed tomography demonstrated normal flow through the aorta and endograft without leak of contrast into the AAA sac or the false lumen of the dissection. Contrast computed tomography 6 months after operation demonstrated that the false lumen was no longer evident.

Video-assisted thoracoscopy

Recent advances in video-imaging and minimally invasive surgical instrumentation have expanded the role of thoracoscopy in the diagnosis and treatment of intrathoracic conditions. This prospective study describes the use of video-assisted thoracoscopy (VAT) in 100 consecutive patients. There were 70 males and 30 females with a mean age of 54.6. They underwent 103 VAT procedures with 41 thoracoscopic biopsies of lung, pleural, chest wall and mediastinal abnormalities, 32 for treatment of recurrent or persistent pneumothorax, 18 for thoracoscopic assessment of pulmonary and pleural tumours and 12 for thoracoscopic resection of peripheral lung lesions, chest wall, mediastinal and pleural tumours. Eighty-one patients had VAT procedures alone while the remaining 19 had VAT proceeding to thoracotomy. The mean operating time for VAT alone was 51 min (range 30-135 min). There were no operative deaths. There were 8 significant complications from which patients recovered fully. Patients who underwent VAT alone were shown to have earlier postoperative mobilization, reduction in parenteral analgesic requirement and reduced length of hospital stay compared to patients undergoing additional thoracotomy. A telephone survey of patients on returning home showed that patients undergoing VAT alone returned to full activity earlier than those who had thoracotomy (mean 9.0 vs mean 19.4 days). This study confirms that VAT is a safe and effective procedure in the management of pulmonary, mediastinal and pleural disease and the treatment of persistent and recurrent pneumothorax. Its role in the resection of pulmonary malignancy remains to be defined.

Isolation of a human YAC contig encompassing a cluster of UGT2 genes and its regional localization to chromosome 4q13

Previously we mapped the gene encoding a human bile acid UDP-glucuronosyltransferase (UGT2B4) to chromosome 4. Here we report the mapping of two additional human UGT2B genes to chromosome 4 utilizing the polymerase chain reaction (PCR) and a panel of human/rodent somatic cell hybrid cell lines. A yeast artificial chromosome contig containing the UGT2B4, UGT2B9, and UGT2B15 genes was isolated, and pulsed-field gel electrophoresis and PCR revealed that several members of the human UGT2B gene subfamily are clustered within a 195-kb region of the YAC contig. These data permitted a provisional ordering of the genes as UGT2B9-UGT2B4-UGT2B15. Fluorescence in situ hybridization analysis, using the YAC DNA, permitted the regional localization of this gene cluster to chromosome 4q13.

A single-blind comparison of intravenous ondansetron, a selective serotonin antagonist, with intravenous metoclopramide in the prevention of nausea and vomiting associated with high-dose cisplatin chemotherapy

Ondansetron (GR 38032F), a selective antagonist of serotonin subtype 3 receptors, is effective in the prevention of emesis associated with cisplatin as well as other chemotherapeutic agents. In this randomized, single-blind, multicenter, parallel group study, we compared the efficacy and safety of intravenous (IV) ondansetron with IV metoclopramide in the prevention of nausea and vomiting associated with high-dose (greater than or equal to 100 mg/m2) cisplatin chemotherapy. Three hundred seven patients receiving their first dose of cisplatin, either alone or in combination with other antineoplastic agents, were randomized to receive ondansetron 0.15 mg/kg IV every 4 hours for three doses or metoclopramide 2 mg/kg IV every 2 hours for three doses, then every 3 hours for three additional doses. The study prohibited the concurrent administration of other antiemetics or dexamethasone. Patients receiving ondansetron had a higher rate of complete protection from emesis (40% v 30%, P = .07), a higher complete plus major response rate (65% v 51%, P = .016), a lower rate of failure (21% v 36%, P = .007), and a lower median number of emetic episodes (one v two, P = .005) than did those receiving metoclopramide. The median time to the first emetic episode was longer on ondansetron (20.5 v 4.3 hours, P less than .001). Adverse events occurred in 48% of patients receiving ondansetron and 69% of those receiving metoclopramide (P less than .001). Akathisia and acute dystonic reactions occurred only on metoclopramide; headache (controlled with acetaminophen) was significantly more frequent with ondansetron. Ondansetron is more effective, produces fewer adverse events, and is easier to administer than metoclopramide for the prevention of emesis associated with high-dose cisplatin chemotherapy.

Studies on cell lineage of metaphyseal bone in repleted scorbutic guinea pigs

Young weanling guinea piglets were placed on a diet deficient only in vitamin C. When they reached a state of severe scorbutus, they were given vitamin C and the morphological differentiation of various mesenchymal cells in the proximal end of the tibia was followed over 7 days. The altering metaphyseal cellular pattern is recorded descriptively as well as quantitatively. Levels of mesenchymal cells, preosteoblasts, osteoblasts, and osteocytes remained relatively steady for 24 h. However, by 48 h there was a precipitous decline of mesenchymal cells with a concomitant rise in recognizable osteogenic cells; this change continued until the 7th day of repletion. At this time, with the exception of the preosteoblasts, the cellular population had returned to about the level in the control animals. Osteoclastic and endothelial cellular movements fluctuated widely during the period of repletion under examination. These results support the concept of separate lines of differentiation for osteoclasts and osteoblasts in the postnatal animal. Moreover, mesenchymal cells appear to be precursors of osteogenic cells.