Primary resistance to docetaxel-based chemotherapy in metastatic breast cancer patients correlates with a high frequency of BRCA1 mutations.
ABSTRACT Docetaxel is a member of the taxoid anticancer agents routinely used in the treatment of high-risk or metastatic breast cancer. A recent study demonstrated that a low response rate to taxane-based neoadjuvant chemotherapy is associated with BRCA1 mutations. Therefore the frequency of BRCA1 mutations in a population of metastatic docetaxel-refractory patients was analyzed.
Nineteen treatment-refractory patients were selected from a group of 175 metastatic breast cancer patients treated with docetaxel-based therapy. DNA isolated from blood or from paraffin-embedded tissue samples was screened for three founder mutations common (>80%) in the Polish population. Additionally, the frequency of BRCA1 mutations was compared with the particular phenotype of breast cancer cells.
BRCA1 mutations were found in 5 of the 19 of patients (26.3%), all 5 being of the 7 patients with triple-negative breast cancer (71%, p<0.002).
This study indicates that the administration of taxanes, especially docetaxel, to metastatic BRCA1 breast cancer patients requires consideration. Moreover, BRCA1 testing in triple-negative breast cancer patients resistant to docetaxel-based treatment may help to identify families with germinal mutations without a history of hereditary breast cancer.
Cancer genetics and cytogenetics 02/2010; 197(1):91-4. · 1.54 Impact Factor
Article: DNA repair signature is associated with anthracycline response in triple negative breast cancer patients.[show abstract] [hide abstract]
ABSTRACT: We hypothesized that a subset of sporadic triple negative (TN) breast cancer patients whose tumors have defective DNA repair similar to BRCA1-associated tumors are more likely to exhibit up-regulation of DNA repair-related genes, anthracycline-sensitivity, and taxane-resistance. We derived a defective DNA repair gene expression signature of 334 genes by applying a previously published BRCA1-associated expression pattern to three datasets of sporadic TN breast cancers. We confirmed a subset of 69 of the most differentially expressed genes by quantitative RT-PCR, using a low density custom array (LDA). Next, we tested the association of this DNA repair microarray signature expression with pathologic response in neoadjuvant anthracycline trials of FEC (n = 50) and AC (n = 16), or taxane-based TET chemotherapy (n = 39). Finally, we collected paraffin-fixed, formalin-embedded biopsies from TN patients who had received neoadjuvant AC (n = 28), and tested the utility of the LDA to discriminate response. Correlation between RNA expression measured by the microarrays and 69-gene LDA was ascertained. This defective DNA repair microarray gene expression pattern was significantly associated with anthracycline response and taxane resistance, with the area under the ordinary receiver operating characteristic curve (AUC) of 0.61 (95% CI = 0.45-0.77), and 0.65 (95% CI = 0.46-0.85), respectively. From the FFPE samples, the 69-gene LDA could discriminate AC responders, with AUC of 0.79 (95% CI = 0.59-0.98). In conclusion, a promising defective DNA repair gene expression signature appears to differentiate TN breast cancers that are sensitive to anthracyclines and resistant to taxane-based chemotherapy, and should be tested in clinical trials with other DNA-damaging agents and PARP-1 inhibitors.Breast Cancer Research and Treatment 08/2010; 123(1):189-96. · 4.43 Impact Factor
Article: Drug therapy for hereditary cancers.[show abstract] [hide abstract]
ABSTRACT: Tumors arising in patients with hereditary cancer syndromes may have distinct drug sensitivity as compared to their sporadic counterparts. Breast and ovarian neoplasms from BRCA1 or BRCA2 mutation carriers are characterized by deficient homologous recombination (HR) of DNA, that makes them particularly sensitive to platinum compounds or inhibitors of poly (ADP-ribose) polymerase (PARP). Outstandingly durable complete responses to high dose chemotherapy have been observed in several cases of BRCA-related metastatic breast cancer (BC). Multiple lines of evidence indicate that women with BRCA1-related BC may derive less benefit from taxane-based treatment than other categories of BC patients. There is virtually no reports directly assessing drug response in hereditary colorectal cancer (CRC) patients; studies involving non-selected (i.e., both sporadic and hereditary) CRC with high-level microsatellite instability (MSI-H) suggest therapeutic advantage of irinotecan. Celecoxib has been approved for the treatment of familial adenomatous polyposis (FAP). Hereditary medullary thyroid cancers (MTC) have been shown to be highly responsive to a multitargeted tyrosine kinase inhibitor vandetanib, which exerts specific activity towards mutated RET receptor. Given the rapidly improving accessibility of DNA analysis, it is foreseen that the potential predictive value of cancer-associated germ-line mutations will be increasingly considered in the future studies.Hereditary Cancer in Clinical Practice 08/2011; 9(1):5. · 1.68 Impact Factor