Abstract OT1-1-11: TBCRC 022: Phase II Trial of Neratinib for Patients with Human Epidermal Growth Factor Receptor 2 (HER2)-Positive Breast cancer and Brain Metastases

Background: 1/3 of women with metastatic HER2+ breast cancer will develop central nervous system (CNS) metastases yet evidence-based treatments for women with progressive CNS disease are limited. Neratinib is an irreversible inhibitor of erbB1, HER2, and erbB4 which has promising activity in HER2+ breast cancer. Preclinical evidence suggests it may cross the blood brain barrier.

Trial Design: This is a multicenter, phase II, open-label study of neratinib for patients with HER2+ breast cancer and brain metastases. Neratinib is administered at 240 mg orally daily during a 28 day cycle. Two cohorts will be enrolled: Cohort 1 will enroll 40 patients with progressive CNS disease; cohort 2 will enroll ≤5 patients who are candidates for surgical excision of intracranial disease. Surgical candidates receive neratinib 7–21 days preoperatively and resume postoperatively. All patients are re-staged every 2 cycles. Those who develop non-CNS progression have an option to extend therapy with trastuzumab+neratinib. Circulating tumor cells (CTC) are collected at baseline and progression; neurocognitive testing, HADS and EORTC QLQ30/BN20 measures are administered at baseline, cycle 2, cycle 3, and progression (cohort 1). Intracranial tumor, cerebrospinal fluid (CSF), and plasma are collected at surgery (cohort 2).

Specific Aims: The primary endpoint is CNS objective response rate (ORR) by composite criteria. Additional endpoints include: non-CNS ORR, progression-free survival, overall survival (OS), site of 1st progression, and toxicity. Correlative and exploratory endpoints include association of CTC count and OS and longitudinal neurocognitive function and quality of life. In an exploratory analysis (cohort 2), we will quantify neratinib concentrations in CSF, intracranial tissue, and plasma and examine associations with response.

Eligibility: Patients must have confirmed HER2+ metastatic disease with ≥1 parenchymal brain lesion measuring ≥10 mm that is new or progressed after completing ≥1 line of standard CNS-directed treatment (cohort 1) or CNS disease that is amenable for surgery, including those without prior CNS treatments (cohort 2). Additional eligibility criteria (cohorts 1,2) include: adequate performance status and end organ/marrow function, and ejection fraction ≥50%. Any number of prior lines of therapy is allowed, including prior lapatinib.

Statistical Methods: Cohort 1 has a 2-stage design with up to 40 patients. CNS ORR is defined as ≥50% reduction in sum volume of CNS target lesions, without evidence of new lesions, progression of non-target CNS lesions, non-CNS disease progression, worsening neurological symptoms, or increase in corticosteroids. CNS lesion measurements are performed centrally by the Harvard Tumor Imaging Metrics Core. If 1/18 patients have a CNS response in the 1st stage, another 22 patients will enroll. With this design, if ≥5 of 40 patients achieve a CNS response, the drug will be deemed worthy of future study. This 2-stage design has 92% power to distinguish between a true CNS ORR of 20% and a null of 6% (one-sided type I error rate=9%).

Accrual: Accrual has begun. Target=45 (cohort 1=40, cohort 2=5)

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr OT1-1-11.

Antisense anti IGF-I cellular therapy of malignant tumours: immune response in cancer patients

The treatment of cancer by antisense anti-IGF-I cellular therapy inducing immune response has evoked interest among many promising strategies. Here, we reported some results obtained from patients with cancer, mainly glioblastoma treated by this strategy, which was also extended to patients with colon carcinoma, ovary cystadenocarcinoma and prostate adenocarcinoma. It was shown that, in the phase I of clinical trial, patients vaccinated with their own tumour cells treated by antisense IGF-I presented a slight increase of temperature. Their peripheral blood lymphocytes showed a shift in the percentage of CD8 effector cells as judged by expression of cell surface markers CD8+ CD28+. Particularly, in two treated patients with glioblastoma, the survival time was 19 and 24 months respectively in comparison to the range of 12 to 15 months observed in the case of classical treatment such as surgery, radiation or chemotherapy. These results, although preliminary, gave indication that the reported strategy could deserve consideration owing to its safety. Furthermore, the increase in the percentage of peripheral blood monomorphonucleated cells (PBMNCs) with effector phenotype, i.e., CD8+ CD28+ in vaccinated patients might explain their prolonged survival time.

Kinetic behavior of the reaction between hydroxyl radical and the SV40 minichromosome

Aqueous solutions containing the minichromosomal form of the virus SV40 and the radical scavenger DMSO were subjected to gamma-irradiation, and the resulting formation of single strand breaks (SSB) was quantified. Under the irradiation conditions, most SSBs were produced as a consequence of hydroxyl radical ((•)OH) reactions. By controlling the competition between DMSO and the viral DNA substrate for (•)OH, we are able to estimate the rate coefficient for the reaction of (•)OH with the SV40 minichromosome. The results cannot be described adequately by homogeneous competition kinetics, but it is possible to describe the rate coefficient for the reaction as a function of the scavenging capacity of the solution. The experimentally determined rate coefficient lies in the range 1×10(9) - 2×10(9) L mol(-1) s(-1) at 10(7) s(-1), and increases with increasing scavenging capacity.

[Nicorandil-associated anal ulceration]

BACKGROUND

Nicorandil is a potassium-channel activator used in the treatment of angina pectoris. The first cases of anal ulcerations induced by nicorandil were published in 2002.

CASE REPORT

A 71-year-old man presented with a 2-year history of anal ulcerations occurring within a few months of initiation of treatment with Nicorandil. Histological tests on a biopsy sample showed granulation tissue with non-specific chronic inflammation. Nicorandil was stopped and this resulted in complete healing of the ulcers after three months.

DISCUSSION

Nicorandil can induce chronic and extensive anal ulcerations. The pathogenesis is unknown. Patients are usually treated with high doses of nicorandil. Dermatologists should be aware of this rare side-effect which heals after withdrawal of the drug.

[Detection of nasal colonization methicillin-resistant Staphylococcus aureus: a prospective study comparing real-time genic amplification assay vs selective chromogenic media]

In contrast to "classical" genic amplification, real-time genic amplification can be performed in every laboratory without the need of sophisticated isolation procedures. Moreover, real-time genic amplification allows an early detection of meticillin resistant Staphylococcus aureus colonization, 2 hours compared to 1 or 2 days for culture.

OBJECTIVE

In order to assess the feasibility on Smartcycler of the IDI-MRSA real-time genic amplification assay in comparison with chromogenic media.

METHODS

A prospective study has been initiated in July 2004: nasal swabs were taken from patients entering the ICU, vascular surgery, diabetology and geriatry wards. During a 4 months period, 682 specimens have been obtained from 508 patients.

RESULTS

Sixty-four (9.3%) patients were positive by genic amplification and selective agar culture (CHROMagar MRSA, MRSASelect and/or ORSAB), 19 (2.9%) were positive by genic amplification only (3 of these patients were under antibiotic treatment); 572 specimens remained negative by both methods. The sensitivity and specificity of this assay were 100% and 96% respectively with a positive predictive value of 70% and negative predictive value of 100%. Initially 82 nasal specimens were unresolved (12%). 38 were resolved following a freeze-thaw cycle. Thus, 44 (6.4%) were unresolved specimens. Comparison between CHROMagar MRSA and MRSASelect showed a good correlation for the detection at 24 hours (5.5% and 5.6% respectively). These two chromogenic media allowed a much better detection of MRSA than ORSAB medium within 24H.

CONCLUSION

The results obtained by the early real-time genic amplification for the detection of meticillin resistant Staphylococcus aureus are promising. Despite 6.4% amplification failure, we consider that IDI-MRSA real-time genic amplification assay represents a significant breakthrough in the detection of colonization.

A novel bacteriocin, thuricin 17, produced by plant growth promoting rhizobacteria strain Bacillus thuringiensis NEB17: isolation and classification

AIMS

The aim of this study was to identify and characterize a compound produced by the plant growth promoting bacterium, Bacillus thuringiensis non-Bradyrhizobium Endophytic Bacterium 17.

METHODS AND RESULTS

The bacterial peptide was analysed and purified via HPLC. Using the disk diffusion assay this peptide inhibited the growth of 16/19 B. thuringiensis strains, 4/4 Bacillus cereus strains, among others, as well as a Gram-negative strain Escherichia coli MM294 (pBS42). Both bactericidal and bacteristatic effects were observed on B. cereus ATCC 14579 and bactericidal effects were observed on B. thuringiensis ssp. thuringiensis Bt1267. The molecular weight of the peptide was estimated via SDS-PAGE and confirmed with Matrix Assisted Laser Desorption Ionization Quadrapole Time of Flight mass spectrometry; its weight is 3162 Da. The peptide is biologically active after exposure to 100 degrees C for 15 min, and within the pH range 1.00-9.25. Its activity disappeared when treated with proteinase K and protease, but not with alpha-amylase or catalase.

CONCLUSIONS

We conclude that this is the first report of a bacteriocin produced by a plant growth promoting rhizobacteria (B. thuringiensis) species and have named the bacteriocin thuricin 17.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our work has characterized a bacteriocin produced by a plant growth promoting bacterium. This strain is previously reported to increase soya bean nodulation.

Radioprotection of plasmid DNA by oligolysines

PURPOSE

To define ionic conditions under which oligolysines condense DNA as assayed by radioprotection of a plasmid substrate. And to compare these conditions with those required by the well-characterized ligands spermidine and hexammine cobalt (III). This will enable a reversible compaction model for plasmid DNA to be devised that models more closely mammalian chromatin than those based on polyamines.

MATERIALS AND METHODS

Aqueous solutions containing plasmid DNA, sodium perchlorate and one of the five ligands trilysine, tetralysine, pentalysine, spermidine, or hexammine cobalt (III) were subjected to gamma-irradiation. The yields of the resulting single-strand breaks were quantified by gel electrophoresis. The effects of tetralysine and pentalysine were also examined by light scattering.

RESULTS

The combination of low concentrations of the ligand and high concentrations of sodium perchlorate produced a relatively high yield of single-strand breaks. In contrast, the combination of high concentrations of the ligand and low concentrations of sodium perchlorate resulted in an approximately 25-fold lower single-strand break yield. The transition between these two break yields took place over very narrow concentration ranges of the ligand. A large change in light scattering occurred at the same concentration. The radioprotective ability of the ligands decreased in the order pentalysine > tetralysine > hexammine cobalt (III) > spermidine > trilysine.

CONCLUSIONS

The effect of the oligolysines is qualitatively very similar to the previously reported radioprotection produced under similar conditions by the polyamines spermidine and spermine. It is caused by condensation of the DNA into a highly compacted form. As peptides, oligolysines are structurally more closely related than other ligands to naturally occurring DNA condensing agents such as histone proteins. Therefore, they may form the basis of a model system suitable for studying DNA damage produced by the direct effect of ionizing radiation (ionization of the DNA itself).

False synergy between vancomycin and beta-lactams against glycopeptide-intermediate Staphylococcus aureus (GISA) caused by inappropriate testing methods

The combination of vancomycin and beta-lactams is often considered synergistic and has been recommended for the treatment of glycopeptide-intermediate Staphylococcus aureus (GISA) infections. In this study, the combination of vancomycin or teicoplanin with different beta-lactams was tested. When using NaCl 4% w/v, for better expression of heterogeneous resistance to beta-lactams, with a longer (48-h) incubation period and a higher (10(7) CFU/mL) inoculum, the association of vancomycin with beta-lactams was antagonistic. However, a synergistic effect was observed for teicoplanin under the same conditions.