Apoptosis-, proliferation, immune function-, and drug resistance- related genes in ER positive, HER2 positive and triple negative breast cancer

The aim of our study was to examine an association between gene expression assessed using a 23-gene microarray and receptor status of breast cancer samples categorized as ER positive, HER2 positive and triple negative subtypes. The ER positive cohort was subsequently divided into Luminal A, Luminal B HER2 negative and Luminal B HER2 positive subtypes. Core- needle biopsies were collected from 78 female patients with inoperable locally advanced breast cancer or resectable tumors suitable for downstaging, before any treatment. Expressions of 23 genes were determined by means of TagMan Low Density Arrays. Analysis of variance was used to select genes with discriminatory potential between receptor subtypes. We introduced a correction for false discovery rates (presented as q values) due to testing multiple hypothesis. Pairwise post-hoc comparisons of receptor subtypes were performed using Tukey 's HSD test. Five genes out of a 23-gene microarray differed significantly in relation to breast cancer receptor-based subtypes. Among these five genes, we identified: BCL2 (p=0.0002, q=0.0009), MKI67 (p=0.0037, q=0.0064), IGF1R (p=0.0040, q=0.0064), FOXC1 (p=0.0113, q=0.0135) and IRF1 (p=0.0435, q=0.0416) as ones showing ER positive, HER2 positive and triple negative -subtype specific expression profiles. When incorporating Luminal A, Luminal B HER2 negative, Luminal B HER2 positive subtypes into analysis, four genes: BCL2 (p=0.0006, q=0.0034), MKI67 (p=0.0078, q=0.0198), FOXC1 (p=0.0102, q=0.0198) and IGF1R (p=0.0174, q=0.0254) were selected. Elevated levels of IGF1R and BCL2 were significantly linked with Luminal A subtype. Triple negative breast cancer subtype was associated with higher expression of IRF1, FOXC1 and MKI67. In HER2 positive cohort lower expression of all five analyzed genes was noted.

Gene expression and pathologic response to neoadjuvant chemotherapy in breast cancer

Pathologic complete response after neoadjuvant systemic treatment appears to be a valid surrogate for better overall survival in breast cancer patients. Currently, together with standard clinicopathologic assessment, novel molecular biomarkers are being exhaustively tested in order to look into the heterogeneity of breast cancer. The aim of our study was to examine an association between 23-gene real-time-PCR expression assay including ABCB1, ABCC1, BAX, BBC3, BCL2, CASP3, CYP2D6, ERCC1, FOXC1, GAPDH, IGF1R, IRF1, MAP2, MAPK 8, MAPK9, MKI67, MMP9, NCOA3, PARP1, PIK3CA, TGFB3, TOP2A, and YWHAZ receptor status of breast cancer core biopsies sampled before neoadjuvant chemotherapy (anthracycline and taxanes) and pathologic response. Core-needle biopsies were collected from 42 female patients with inoperable locally advanced breast cancer or resectable tumors suitable for downstaging, before any treatment. Expressions of 23 genes were determined by means of TagMan low density arrays. Analysis of variance was used to select genes with discriminatory potential between receptor subtypes. We introduced a correction for false discovery rates (presented as q values) due to multiple hypothesis testing. Statistical analysis showed that seven genes out of a 23-gene real-time-PCR expression assay differed significantly in relation to pathologic response regardless of breast cancer subtypes. Among these genes, we identified: BAX (p = 0.0146), CYP2D6 (p = 0.0063), ERCC1 (p = 0.0231), FOXC1 (p = 0.0048), IRF1 (p = 0.0022), MAP2 (p = 0.0011), and MKI67 (p = 0.0332). The assessment of core biopsy gene profiles and receptor-based subtypes, before neoadjuvant therapy seems to predict response or resistance and to define new signaling pathways to provide more powerful classifiers in breast cancer, hence the need for further research.

Fatty acid profile and influence of oxythiamine on fatty acid content in Malassezia pachydermatis, Candida albicans and Saccharomyces cerevisiae

Malassezia pachydermatis and Candida albicans are fungi involved in the skin diseases and systemic infections. The therapy of such infections is difficult due to relapses and problems with pathogen identification. In our study, we compare the fatty acids profile of M. pachydermatis, C. albicans and S. cerevisiae to identify diagnostic markers and to investigate the effect of oxythiamine (OT) on the lipid composition of these species. Total fatty acid content is threefold higher in C. albicans and M. pachydermatis compared with S. cerevisiae. These two species have also increased level of polyunsaturated fatty acids (PUFA) and decreased content of monounsaturated fatty acids (MUFA). We noted differences in the content of longer chain (>18) fatty acids between studied species (for example a lack of 20 : 1 in S. cerevisiae and 22 : 0 in M. pachydermatis and C. albicans). OT reduces total fatty acids content in M. pachydermatis by 50%. In S. cerevisiae, OT increased PUFA whereas it decreased MUFA content. In C. albicans, OT decreased PUFA and increased MUFA and SFA content. The results show that the MUFA to PUFA ratio and the fatty acid profile could be useful diagnostic tests to distinguish C. albicans, M. pachydermatis and S. cerevisiae, and OT affected the lipid metabolism of the investigated species, especially M. pachydermatis.

Can We Talk about CD4+CD28– Lymphocytes as a Risk Factor for Ischemic Stroke?

BACKGROUND

CD4+CD28- lymphocytes are implicated in the destabilization of atheromatous plaque, leading to acute coronary episodes. One may ask whether these cells play a similar role in ischemic stroke pathogenesis with an atherosclerotic background.

METHODS

Flow cytometry was applied to determine the percentage of CD4+CD28- lymphocytes in the peripheral blood of patients during the acute phase of their first ischemic stroke (group I) and in patients without a history of stroke but with two of the most important risk factors (hypertension, diabetes) for atherosclerosis-related ischemic stroke (group II). The results were compared with healthy controls.

RESULTS

The median percentages of CD4+CD28- lymphocytes in groups I and II did not differ significantly, but for each of these groups the percentage was higher than in the control group. The time of blood sampling from onset of stroke, presence of the ischemic focus in the CT brain scan and severity of neurological deficits did not correlate with the percentage of CD4+CD28- lymphocytes.

CONCLUSIONS

We conclude that CD4+CD28- lymphocytes are implicated in mechanisms enhancing the risk of acute ischemic stroke and not a consequence of stroke.

Stimulatory effect of LH, PGE2 and progesterone on StAR protein, cytochrome P450 cholesterol side chain cleavage and 3beta hydroxysteroid dehydrogenase gene expression in bovine luteal cells

The aim of these studies was to investigate the effect of LH, progesterone (P4), PGE, noradrenaline (NA) and a nitric oxide donor, S-nitroso-N-acetylpenicillamine (S-NAP), on steroid acute regulatory protein (StAR), 3beta-hydroxysteroid dehydrogenase (3beta-HSD) and cytochrome P450 side chain cleavage (P450scc) gene expression and on the synthesis of their protein products. Bovine luteal cells were collected and prepared on days 6-10 of the estrous cycle and preincubated in vitro for 24 h. Thereafter, medium was changed and supplemented with one of six treatments: control medium, LH (100 ng/ml), P4 (10(-5)M), PGE2 (10(-6)M), NA (10(-5)M) or S-NAP (10(-4)M). In Experiment 1, luteal cells (10(6)/well) were incubated for 3, 6, 18 and 24 h. After incubation, total RNA was isolated and P4 concentrations in medium was determined. Semiquantitative RT-PCR was used to measure gene expression. In Experiment 2, luteal cells were preincubated for 24h, then stimulated as in Experiment 1. Total protein was isolated from lysed cells and Western blot analysis was performed using specific antibodies against the StAR, 3beta-HSD and cytochrome P450scc proteins. Bands were analyzed by means of KODAK 1D Image Analysis Software. In Experiment 1, LH and PGE2 stimulated secretion of progesterone from luteal cells. Concentrations of mRNA for StAR, 3beta-HSD, cytochrome P450scc were increased after 6 h in cells stimulated with LH, PGE2 and P4 (P<0.05). Gene expression was not affected by NA. In Experiment 2, LH, P4 and PGE2 induced an increase in the concentration of these three proteins. S-NAP inhibited both concentrations of mRNA and protein for StAR, 3beta-HSD, cytochrome P450scc. Therefore, the increase in secretion of P4 induced by LH and PGE2 is associated with increases in StAR, 3beta-HSD and cytochrome P450scc gene expression. This genomic response may be mediated in part through a positive effect of P4 on the expression of these genes observed in this experiment.