Morphometric and immunohistochemical study of angiogenic marker expressions in invasive ductal carcinomas of the human breast

Breast cancer is the leading cause of cancer deaths among women. Results from experimental studies suggest that tumour progression and metastasis in breast cancer are angiogenesis dependant. The College of American Pathologists has stated that further study of quantification of tumour angiogenesis is still required to demonstrate its prognostic value in breast cancer. In this study, not only the microvascular density (MVD), but also the vascular area ratio (VAR), and the vascular count in different grades of invasive ductal breast carcinoma were assessed using a pan-endothelial marker, CD34, and monoclonal antibody to CD105, by employing computer assisted morphometric measurements. In addition, quantitative expression of vascular endothelial growth factor (VEGF) was detected. Correlation of the vascular parameters and VEGF expression with the different grades of invasive ductal breast carcinoma was clarified. Immunohistochemical staining for the CD105, CD34, and VEGF antibodies were performed in 25 patients with invasive ductal carcinoma in King Fahd Hospital, Saudi Arabia. Normal breast tissue samples comprised 15 specimens detected at the safety margin of the malignant breast cases were collected. Positive CD34 stained blood-vessel endothelial cells were observed in all normal breast tissues. In contrast, CD105 and VEGF expression were not expressed in the normal breast ducts and lobules. Widespread staining for CD34, to a lesser extent CD105, and VEGF expression were seen in all tumour specimens with different grades. Significant differences in the vascular parameters, stained with antiCD34, were observed between normal breast tissues and invasive ductal carcinoma. In addition, the vascular parameters stained with antiCD34 and antiCD105, and the percentage of VEGF expression in the three grades of invasive ductal carcinomas showed significant differences with positive correlations. In conclusion, MVD as well as VAR are considered to reflect the final result of the tumour angiogenesis cascade. In addition, VEGF expression was found to be a useful angiogenic marker. However, few cases were VEGF negatively stained. Thus, the expression of MVD, VAR, and to a lesser extent VEGF might be reference predictors for the biological behaviour and prognosis of breast carcinoma

Millisecond-Timescale Local Network Coding in the Rat Primary Somatosensory Cortex

Correlation among neocortical neurons is thought to play an indispensable role in mediating sensory processing of external stimuli. The role of temporal precision in this correlation has been hypothesized to enhance information flow along sensory pathways. Its role in mediating the integration of information at the output of these pathways, however, remains poorly understood. Here, we examined spike timing correlation between simultaneously recorded layer V neurons within and across columns of the primary somatosensory cortex of anesthetized rats during unilateral whisker stimulation. We used Bayesian statistics and information theory to quantify the causal influence between the recorded cells with millisecond precision. For each stimulated whisker, we inferred stable, whisker-specific, dynamic Bayesian networks over many repeated trials, with network similarity of 83.3±6% within whisker, compared to only 50.3±18% across whiskers. These networks further provided information about whisker identity that was approximately 6 times higher than what was provided by the latency to first spike and 13 times higher than what was provided by the spike count of individual neurons examined separately. Furthermore, prediction of individual neurons' precise firing conditioned on knowledge of putative pre-synaptic cell firing was 3 times higher than predictions conditioned on stimulus onset alone. Taken together, these results suggest the presence of a temporally precise network coding mechanism that integrates information across neighboring columns within layer V about vibrissa position and whisking kinetics to mediate whisker movement by motor areas innervated by layer V