Novel approaches in the detection and characterisation of circulating and micrometastatic tumour cells in epithelial malignancies

The detection of disseminated tumour cells has introduced a new opportunity to evaluate the diverse biological characteristics of the primary tumour that might favour the early dissemination of its cells, since conventional risk factors do not provide specific or sensitive enough information. An immunocytochemical (ICC) assay established during the study, was shown to be capable of detecting one cytokeratin-positive (CK+VE) cell in 2 x 10 mononuclear cells (MNCs), by attachment to microscope slides coated with Cell-Tak Cell and Tissue Adhesive. The clinical data indicate that 57% of samples examined from patients undergoing therapy for carcinoma of the breast (BrCa), showed detectable CK+VE cells in peripheral blood (PB) or bone marrow (BM) aspirate samples. The incidence of tumour cell contaminated PB samples was higher in patients with metastatic disease than patients without overt metastatic disease (p<0.0001). In contrast, all control samples consistently tested negative for circulating CK+VE cells. Detection of micrometastases may also help to determine prognosis and allow development of new therapeutic approaches. In a study of the impact of chemotherapy on the presence of tumour cells in the PB, 24/33 high-risk nonmetastatic BrCa patients had detectable tumour cells pre-chemotherapy (steady state). A reduction, but not complete eradication, in the number of circulating CK+VE cells was observed in all patients during subsequent courses of chemotherapy (p<0.0001). This demonstrates that chemotherapy is not effective in eliminating all PB/BM tumour cells even in chemo-responsive patients. In addition, the phenotype of these cells may determine whether overt metastases will develop. A highly sensitive assay combining tumour cell enrichment with immunolabelling and fluorescence in situ hybridization (FISH), was developed to characterise cytogenetically aberrant tumour cells in haematopoietic samples. Using DNA probes to the Her-2/neu (c-erbB-2) oncogene and chromosomes 7, 8, and 17 hybridized to metaphase chromosomes and immunolabelled interphase cells, oncogene overamplification and chromosomal alterations have been established. Additional studies have confirmed an association between the level of Her- 2lneu gene amplification, clinical status and response to chemotherapy. Genotypic analyses suggest that Her-2/neu overexpression may enhance metastatic potential possibly by promoting steps in the invasion and metastasis process and that "shed" Her-2/neu+VE/CK+VE PB tumour cells might "home" to the BM, resulting in aggressive tumour behaviour and a poor prognosis

A novel murine model of allogeneic vaccination against prostate cancer

Prostate cancer continues to be a major cause of death in men. Surgical and medical treatments of the disease have improved, but metastasic disease remains a significant clinical problem. Novel therapies such as whole cell vaccination offer the potential of treating disease by stimulating the immune system. To study the efficacy of a whole cell vaccine in prostate cancer two strains of mice were used: C57BL/6 (H-2Kb) and C3H/HeJ (H-2Kk) in combination with four different cell lines. Thus, a model was constructed of allogeneic and syngeneic vaccine, as well as a challenge tumour for each strain. Two novel cell lines were developed during this study. Firstly, the non tumourigeneic PMC-1 was derived from a normal mouse prostate and immortalized with HPV16. Secondly, the tumourigeneic PMC-1 C6ras1p1 was transformed with human ras gene which formed tumours in both SCID and C3H/HeJ mice. Protection, and the nature of the immune response to syngeneic and allogeneic vaccine, in males and females was examined in both strains. Vaccination with both syngeneic and allogeneic irradiated whole cell vaccines induced protection from syngeneic challenge in females. However, no protection was observed when allogeneic vaccine was given to male mice. This correlated with the immune response. Two types of cellular immune responses were generated in females. A NK-mediated response was observed in C57BL/6 mice, whilst C3H/HeJ mice developed a CTL response. Little or no cellular immune response was observed in males. The cytokine profile in C3H/HeJ females was a mixture of Th1 and Th2 whilst a mainly Th1 profile was observed in C57BL/6 mice. Male mice showed a diminished cytokine secretion compared to females which was further depressed after challenge. The difference in immunity was largely as expected, since tolerance to prostate antigens should not normally develop in female mice. However, this makes this model particularly relevant clinically since it directly mimics the human situation and thus may accelerate the development of whole cell vaccines for clinical use

Bortezomib plus rituximab versus rituximab in patients with high-risk, relapsed, rituximab-na\uefve or rituximab-sensitive follicular lymphoma: subgroup analysis of a randomized phase 3 trial

BACKGROUND: The randomized phase 3 LYM3001 trial in relapsed follicular lymphoma (FL) demonstrated higher overall (ORR) and complete response (CR) rates and prolonged progression-free survival (PFS) with bortezomib-rituximab versus rituximab. We report findings in high-risk patients (FL International Prognostic Index [FLIPI] score 653, and high tumor burden by modified Groupe d'Etude des Lymphomas Folliculaires [GELF] criteria). METHODS: Patients aged 6518 years with grade 1/2 FL, 651 measurable lesion, and documented relapse or progression following prior therapy, rituximab-na\uefve or rituximab-sensitive, were enrolled at 164 centers in 29 countries across Europe, the Americas, and Asia-Pacific. Patients were randomized (1:1) to five 5-week cycles of bortezomib-rituximab (bortezomib 1.6 mg/m2, days 1, 8, 15, and 22, all cycles; rituximab 375 mg/m2, days 1, 8, 15, and 22, cycle 1, and day 1, cycles 2-5; N=336) or rituximab alone (N=340). Randomization was stratified by FLIPI score, prior rituximab, time since last dose of anti-lymphoma therapy, and geographical region. The primary endpoint of the study was PFS. RESULTS: 103 bortezomib-rituximab and 98 rituximab patients had high-risk FL. The ORR was 59% versus 37% (p=0.002), the CR/CRu rate was 13% versus 6% (p=0.145), and the durable response rate was 45% versus 26% (p=0.008) with bortezomib-rituximab versus rituximab. Median PFS was 9.5 versus 6.7 months (hazard ratio [HR] 0.667, p=0.012) with bortezomib-rituximab versus rituximab; median time to progression was 10.9 versus 6.8 months (HR 0.656, p=0.009); median time to next anti-lymphoma treatment was 14.8 versus 9.1 months (HR 0.762, p=0.103); and the 1-year Overall Survival rate was 83.1% versus 76.6%. Overall, 51% of bortezomib-rituximab and 32% of rituximab patients reported grade 653 adverse events, including neutropenia (18%, 6%), anemia (4%, 5%), diarrhea (8%, 0%), thrombocytopenia (5%, 2%), and sensory neuropathy (1%, 0%). CONCLUSIONS: High-risk FL patients treated with bortezomib-rituximab had significantly higher ORR and longer PFS than patients receiving rituximab alone, with greater clinical benefit than in the overall study population; additional toxicity was acceptable and did not affect treatment feasibility. TRIAL REGISTRATION: The phase 3 LYM3001 trial is registered with ClinicalTrials.gov, with the identifier NCT00312845

Bortezomib plus rituximab versus rituximab alone in patients with relapsed, rituximab-naive or rituximab-sensitive, follicular lymphoma: a randomised phase 3 trial.

Johnson & Johnson Pharmaceutical Research & Development and Millennium Pharmaceuticals, Inc