202 research outputs found
Understanding endocrine resistance: the critical need for sequential samples from clinical breast cancer and novel in vitro models
Clinical significance of preoperative serum interleukin-6 and C-reactive protein level in breast cancer patients
<p>Abstract</p> <p>Background</p> <p>Breast cancer is a disease that continues to plague females during their entire lifetime. IL-6 and CRP are found to be elevated in various inflammatory and malignant diseases and their levels are found to correlate with the extent of the disease. The primary objective of this study was to determine the preoperative serum levels of IL-6 and CRP in breast carcinoma, and to correlate them with the staging of the disease and the prognosis.</p> <p>Methods</p> <p>59 female patients admitted for breast cancer were identified for the study and were subjected to thorough evaluation. Serum levels of IL-6 were assessed via Enzyme-Linked Immuno-Sorbent Assay (ELISA), and CRP was measured via immunoturbidimetry. Histological findings included tumour size, lymph node (LN) metastasis, and tumour staging. Relevant investigations were made to find out the presence of distant metastasis. Statistical analysis of the data was then processed.</p> <p>Results</p> <p>Increases in cancer invasion and staging are generally associated with increases in preoperative serum IL-6 levels. IL-6 and CRP levels correlated with LN metastasis (P < 0.001, P < 0.001) and TNM stage (P < 0.001, P < 0.001). Tumour invasion and the presence of distant metastasis is associated with higher IL-6 levels (P = 0.001, P = 0.009). When we established the cutoff value for IL-6 level (20.55 pg/dl) by ROC curve, we noted a significant difference in overall survival (OS; P = 0.008). However, CRP evidenced no significance with regard to patient's OS levels. Serum IL-6 levels were correlated positively with CRP levels (r2 = 0.579, P < 0.01)</p> <p>Conclusion</p> <p>Serum levels of IL-6 correlates well with the extent of tumor invasion, LN metastasis, distant metastasis and TNM staging thus enveloping all aspects of breast cancer.</p
Genetic Predisposition for Type 2 Diabetes, but Not for Overweight/Obesity, Is Associated with a Restricted Adipogenesis
BACKGROUND: Development of Type 2 diabetes, like obesity, is promoted by a genetic predisposition. Although several genetic variants have been identified they only account for a small proportion of risk. We have asked if genetic risk is associated with abnormalities in storing excess lipids in the abdominal subcutaneous adipose tissue. METHODOLOGY/PRINCIPAL FINDINGS: We recruited 164 lean and 500 overweight/obese individuals with or without a genetic predisposition for Type 2 diabetes or obesity. Adipose cell size was measured in biopsies from the abdominal adipose tissue as well as insulin sensitivity (HOMA index), HDL-cholesterol and Apo AI and Apo B. 166 additional non-obese individuals with a genetic predisposition for Type 2 diabetes underwent a euglycemic hyperinsulinemic clamp to measure insulin sensitivity. Genetic predisposition for Type 2 diabetes, but not for overweight/obesity, was associated with inappropriate expansion of the adipose cells, reduced insulin sensitivity and a more proatherogenic lipid profile in non-obese individuals. However, obesity per se induced a similar expansion of adipose cells and dysmetabolic state irrespective of genetic predisposition. CONCLUSIONS/SIGNIFICANCE: Genetic predisposition for Type 2 diabetes, but not obesity, is associated with an impaired ability to recruit new adipose cells to store excess lipids in the subcutaneous adipose tissue, thereby promoting ectopic lipid deposition. This becomes particularly evident in non-obese individuals since obesity per se promotes a dysmetabolic state irrespective of genetic predisposition. These results identify a novel susceptibility factor making individuals with a genetic predisposition for Type 2 diabetes particularly sensitive to the environment and caloric excess
The Bloom's syndrome helicase (BLM) interacts physically and functionally with p12, the smallest subunit of human DNA polymerase Ξ΄
Bloom's syndrome (BS) is a cancer predisposition disorder caused by mutation of the BLM gene, encoding a member of the RecQ helicase family. Although the phenotype of BS cells is suggestive of a role for BLM in repair of stalled or damaged replication forks, thus far there has been no direct evidence that BLM associates with any of the three human replicative DNA polymerases. Here, we show that BLM interacts specifically in vitro and in vivo with p12, the smallest subunit of human POL Ξ΄ (hPOL Ξ΄). The hPOL Ξ΄ enzyme, as well as the isolated p12 subunit, stimulates the DNA helicase activity of BLM. Conversely, BLM stimulates hPOL Ξ΄ strand displacement activity. Our results provide the first functional link between BLM and the replicative machinery in human cells, and suggest that BLM might be recruited to sites of disrupted replication through an interaction with hPOL Ξ΄. Finally, our data also define a novel role for the poorly characterized p12 subunit of hPOL Ξ΄
Potentiation of the cytotoxicity of thymidylate synthase (TS) inhibitors by dipyridamole analogues with reduced Ξ±1-acid glycoprotein binding
The effect of long-term homocysteine-lowering on carotid intima-media thickness and flow-mediated vasodilation in stroke patients: a randomized controlled trial and meta-analysis
<p>Abstract</p> <p>Background</p> <p>Experimental and epidemiological evidence suggests that homocysteine (tHcy) may be a causal risk factor for atherosclerosis. B-vitamin supplements reduce tHcy and improve endothelial function in short term trials, but the long-term effects of the treatment on vascular structure and function are unknown.</p> <p>Methods</p> <p>We conducted a sub-study of VITATOPS, a randomised, double-blind, placebo-controlled intervention trial designed to test the efficacy of long term B-vitamin supplementation (folic acid 2 mg, vitamin B<sub>6 </sub>25 mg and vitamin B<sub>12 </sub>0.5 mg) in the prevention of vascular events in patients with a history of stroke. We measured carotid intima-medial thickness (CIMT) and flow-mediated dilation (FMD) at least two years after randomisation in 162 VITATOPS participants. We also conducted a systematic review and meta-analysis of studies designed to test the effect of B-vitamin treatment on CIMT and FMD.</p> <p>Results</p> <p>After a mean treatment period of 3.9 Β± 0.9 years, the vitamin-treated group had a significantly lower mean plasma homocysteine concentration than the placebo-treated group (7.9 ΞΌmol/L, 95% CI 7.5 to 8.4 versus 11.8 ΞΌmol/L, 95% CI 10.9 to 12.8, p < 0.001). Post-treatment CIMT (0.84 Β± 0.17 mm vitamins versus 0.83 Β± 0.18 mm placebo, p = 0.74) and FMD (median of 4.0%, IQR 0.9 to 7.2 vitamins versus 3.0%, IQR 0.6 to 6.6 placebo, p = 0.48) did not differ significantly between groups. A meta-analysis of published randomised data, including those from the current study, suggested that B-vitamin supplements should reduce CIMT (-0.10 mm, 95% CI -0.20 to -0.01 mm) and increase FMD (1.4%, 95% CI 0.7 to 2.1%). However, the improvement in endothelial function associated with homocysteine-lowering treatment was significant in short-term studies but not in longer trials.</p> <p>Conclusion</p> <p>Although short-term treatment with B-vitamins is associated with increased FMD, long-term homocysteine-lowering did not significantly improve FMD or CIMT in people with a history of stroke.</p> <p>Trial Registration</p> <p>Clinical Trial Registration URL: <url>http://www.actr.org.au/</url></p> <p>Trial Registration number: 12605000005651</p
Severe Osteogenesis Imperfecta in Cyclophilin BβDeficient Mice
Osteogenesis Imperfecta (OI) is a human syndrome characterized by exquisitely fragile bones due to osteoporosis. The majority of autosomal dominant OI cases result from point or splice site mutations in the type I collagen genes, which are thought to lead to aberrant osteoid within developing bones. OI also occurs in humans with homozygous mutations in Prolyl-3-Hydroxylase-1 (LEPRE1). Although P3H1 is known to hydroxylate a single residue (pro-986) in type I collagen chains, it is unclear how this modification acts to facilitate collagen fibril formation. P3H1 exists in a complex with CRTAP and the peptidyl-prolyl isomerase cyclophilin B (CypB), encoded by the Ppib gene. Mutations in CRTAP cause OI in mice and humans, through an unknown mechanism, while the role of CypB in this complex has been a complete mystery. To study the role of mammalian CypB, we generated mice lacking this protein. Early in life, Ppib-/- mice developed kyphosis and severe osteoporosis. Collagen fibrils in Ppib-/- mice had abnormal morphology, further consistent with an OI phenotype. In vitro studies revealed that in CypBβdeficient fibroblasts, procollagen did not localize properly to the golgi. We found that levels of P3H1 were substantially reduced in Ppib-/- cells, while CRTAP was unaffected by loss of CypB. Conversely, knockdown of either P3H1 or CRTAP did not affect cellular levels of CypB, but prevented its interaction with collagen in vitro. Furthermore, knockdown of CRTAP also caused depletion of cellular P3H1. Consistent with these changes, post translational prolyl-3-hydroxylation of type I collagen by P3H1 was essentially absent in CypBβdeficient cells and tissues from CypBβknockout mice. These data provide significant new mechanistic insight into the pathophysiology of OI and reveal how the members of the P3H1/CRTAP/CypB complex interact to direct proper formation of collagen and bone
c-erbB2/neu gene and chromosome 17 analysis in breast cancer by FISH on archival cytological fine-needle aspirates
Determination of c-myc amplification and overexpression in breast cancer patients: evaluation of its prognostic value against c-erbB-2, cathepsin-D and clinicopathological characteristics using univariate and multivariate analysis
C-myc and c-erbB-2 amplification and/or overexpression as well as total cathepsin-D (CD) concentration have been reported to be associated with poor prognosis in breast cancer. The prognostic significance, however, remains somewhat controversial, partly because of discrepancies among the different methodologies used. We determined the amplification and overexpression of c-myc oncogene in 152 breast cancer patients and examined its prognostic value in relation to c-erbB-2 amplification and overexpression, high concentration of CD (β₯ 60 pmol mgβ1 protein) and standard clinicopathological prognostic factors of the disease. High CD concentration, as well as c-myc amplification and overexpression, proved to be the best of the new variables examined for prediction of early relapse (ER; before 3 years). After multivariate analysis only CD remained significant, which suggests that the prognostic power of these variables is similar. Using univariate analysis we proved that c-myc amplification and overexpression were highly significant for disease-free survival (DFS) (P = 0.0016 and P = 0.0001 respectively) and overall survival (OS) (P < 0.0001 and P = 0.0095 respectively), although by multivariate analysis c-myc overexpression was statistically significant only for DFS (P = 0.0001) and c-myc amplification only for OS (P = 0.0006). With regard to c-erbB-2, only its overexpression appeared to be significant for DFS and OS, although after multivariate analysis its prognostic power was weaker (P = 0.030 and P = 0.024 respectively). c-myc amplification and overexpression exhibited a tendency for locoregional recurrence (LRR) (P = 0.0024 and P = 0.0075 respectively), however, their prognostic value was lower after multivariate analysis and only CD remained significant. Β© 1999 Cancer Research Campaig
- β¦