Beneficial Effects of Mifepristone Treatment in Patients with Breast Cancer Selected by the Progesterone Receptor Isoform Ratio: Results from the MIPRA Trial.

PURPOSE: Preclinical data suggest that antiprogestins inhibit the growth of luminal breast carcinomas that express higher levels of progesterone receptor isoform A (PRA) than isoform B (PRB). Thus, we designed a presurgical window of opportunity trial to determine the therapeutic effects of mifepristone in patients with breast cancer, based on their high PRA/PRB isoform ratio (MIPRA; NCT02651844). PATIENTS AND METHODS: Twenty patients with luminal breast carcinomas with PRA/PRB > 1.5 (determined by Western blots), and PR ≥ 50%, naïve from previous treatment, were included for mifepristone treatment (200 mg/day orally; 14 days). Core needle biopsies and surgical samples were formalin fixed for IHC studies, while others were snap-frozen to perform RNA sequencing (RNA-seq), proteomics, and/or Western blot studies. Plasma mifepristone levels were determined using mass spectrometry. The primary endpoint was the comparison of Ki67 expression pretreatment and posttreatment. RESULTS: A 49.62% decrease in Ki67 staining was observed in all surgical specimens compared with baseline (P = 0.0003). Using the prespecified response parameter (30% relative reduction), we identified 14 of 20 responders. Mifepristone induced an increase in tumor-infiltrating lymphocytes; a decrease in hormone receptor and pSer118ER expression; and an increase in calregulin, p21, p15, and activated caspase 3 expression. RNA-seq and proteomic studies identified downregulated pathways related to cell proliferation and upregulated pathways related to immune bioprocesses and extracellular matrix remodeling. CONCLUSIONS: Our results support the use of mifepristone in patients with luminal breast cancer with high PRA/PRB ratios. The combined effects of mifepristone and estrogen receptor modulators warrant clinical evaluation to improve endocrine treatment responsiveness in these patients. See related commentary by Ronchi and Brisken, p. 833.

The use of tetradecanoylphorbol acetate-stimulated peripheral blood cells enhances the prognostic value of interphase fluorescence in situ hybridization in patients with chronic lymphocytic leukemia.

Interphase fluorescence in situ hybridization (I-FISH) studies have a remarkable prognostic value in patients with chronic lymphocytic leukemia (CLL). I-FISH studies can be performed either on tetradecanoylphorbol acetate stimulated peripheral blood cells (I-FISH-TPA) or unstimulated peripheral blood mononuclear cells (I-FISH-PBMC). The aim of the study was to evaluate whether this finding was clinically relevant in a group of 235 patients with CLL. Fifty-six patients had both I-FISH-TPA and I-FISH-PBMC results. Compared with uncultured cells, the cytogenetic detection rate rose from 57 to 80% with the use of TPA-stimulated cells (P = 0.014). I-FISH-TPA provided a better prediction of treatment-free survival compared with I-FISH-PBMC (P = 0.031 vs. 0.166). Then, I-FISH-PBMC results from 93 historical patients were compared with 86 recent patients with I-FISH-TPA results. Genomic aberrations were detected in 46 and 67% of patients from the I-FISH-PBMC and I-FISH-TPA cohorts, respectively. The detection rate of 13q deletion as the only aberration increased from 10% with I-FISH-PBMC to 37% with I-FISH-TPA (P = 0.006). In conclusion, I-FISH-TPA increased the detection rate of 13q deletion and had an improved prognostic value compared with I-FISH-PBMC.

Detection of chromosomal abnormalities in chronic lymphocytic leukemia increased by interphase fluorescence in situ hybridization in tetradecanoylphorbol acetate-stimulated peripheral blood cells.

Interphase fluorescent in situ hybridization on unstimulated peripheral blood mononuclear cells (I-FISH-PBMC) is used to detect chromosomal abnormalities such as 11q-, 13q-, 17p-, and trisomy 12 in chronic lymphocytic leukemia (CLL). A total of 56 samples from 49 patients with CLL were studied using commercially available probes for chromosome regions 11q22.3 (ATM), 13q14 (13S272), 17p13 (p53) and 12 centromere (D12Z3). We compared the results obtained with I-FISH-PBMC and those with I-FISH on TPA (tetradecanoylphorbol acetate; phorbol-12-myristate-13-acetate) stimulated peripheral blood cells (I-FISH-TPA) used for conventional cytogenetics, to evaluate the usefulness of I-FISH-TPA. The proportion of abnormal nuclei obtained with the I-FISH-TPA was higher than that found with I-FISH-PBMC (P < 0.001). Consequently, 15 cases with a negative or borderline result with I-FISH-PBMC became positive with I-FISH-TPA for 11q- (n = 2), 13q- (n = 9), and trisomy 12 (n = 4). In all but one of these, chromosomal abnormalities were confirmed by either metaphase FISH or conventional G-banding. Detection of cytogenetic aberrations thus increased from 51% with I-FISH-PBMC to 78% with I-FISH-TPA. Notably, all 15 of the cases that reached the diagnostic thresholds for 11q-, 13q-, and trisomy 12 had a slight lymphocytosis. An absolute lymphocyte count <8.7 x 10(9)/L was found to be the critical threshold (P = 0.037) below which I-FISH-TPA rather than I-FISH-PBMC should be performed. Not only could I-FISH-TPA detect a higher proportion of abnormal interphase nuclei, but it could also identify abnormal CLL cases that might be overlooked with use of I-FISH-PBMC, especially those with low absolute lymphocyte counts. I-FISH-TPA is thus a reliable technique for clinical diagnostics in CLL.

Validación de un método cromatográfico para la cuantificación de mefenesina en tabletas de producción nacional / A chromatographic method validation to quantify tablets Mephenesine of national production

Se realizó la validación de un método analítico por cromatografía líquida de alta eficiencia para la cuantificación de mefenesina en tabletas de 500 mg reformuladas recientemente. Con respecto a su aplicación al control de calidad, la validación incluyó los parßmetros linealidad, exactitud, precisión y selectividad. Los resultados fueron satisfactorios en el rango de 50-150 por ciento. Para su empleo en estudios posteriores de estabilidad química, se evaluó adicionalmente la selectividad para estabilidad y la sensibilidad. Los límites de detección y cuantificación estimados resultaron adecuados y el método fue selectivo frente a los posibles productos de degradación.

Authors made validation of an analytical method by high performance liquid chromatography (HPLC) for quantification of Mephenesine in recently reformulated 500 mg tablets. With regard to its application to quality control, validation included the following parameters: linearity, accuracy, precision, and selectivity. Results were satisfactory within 50-150 percent rank. In the case of its use in subsequent studies of chemical stability, the selectivity for stability and sensitivity was assessed. Estimated detection and quantification limits were appropriate, and the method was selective versus the possible degradation products.