Analytical and clinical performance of progesterone receptor antibodies in breast cancer.

OBJECTIVE: Comparison of analytical and immunohistochemical performance of progesterone receptor (PR) antibodies with correlation to recurrence of invasive breast cancer treated with endocrine therapy. METHODS: The binding-affinity kinetics of PR clones 1E2, 1A6, 16 and 636 were compared using synthetic peptides derived from identified epitopes on a Biacore T200. A cohort of 351 cases (Hormone Receptor (HR)+/HER2-) were stained for PR expression with immunohistochemistry (IHC) and scored according to ASCO/CAP criteria. RESULTS: The stability of the antigen/antibody complex was greater for the 1E2 clone compared to 1A6, 16 and 636 clones. PR IHC on archival tissue resulted in 94.3% (299/317) concordance with clones. CONCLUSION: Clones evaluated in this study had a high level of concordance with IHC despite PR (1E2) demonstrating higher analytical binding properties than other clones. In a minority of cases (1.3% for 1E2 and 2.5% for 636) IHC results could convert estrogen receptor (ER)-/PR- to ER-/PR+ tumors, making these patients potentially eligible for endocrine therapy.

Immunohistochemical analysis of the monoclonal antibody 4B5 in breast tissue expressing human epidermal growth factor receptor 4 (HER4).

AIMS: A recent study examining the specificity of human epidermal growth factor receptor (HER) 2 pharmacodiagnostic antibodies demonstrated that CB11 and 4B5 stain both HER2-transfected and HER4-transfected cell lines. However, there has been no evidence showing that 4B5 has affinity for HER4 in clinically obtained tissues, and, if so, whether this has any impact on the assessment of HER2. We therefore sought to determine the expression of membrane-bound HER4 in clinical breast carcinomas, and evaluate its impact on the clinical utility of 4B5 in determining HER2 status. METHODS AND RESULTS: Breast carcinomas were assessed by immunohistochemistry (IHC) for membrane-bound HER4 using anti-HER4 clone E200. HER2 expression in these cases was then assessed using anti-HER2 clone 4B5, and a reference clone, SP3. In all 117 membrane HER4-positive cases (out of 241), 4B5 scored equal to or less than the reference anti-HER2 clone SP3. Eighteen cases were positive for membrane-bound HER4 by E200 and negative by 4B5, including a membrane HER4 level 3+ case. CONCLUSIONS: No cross-reactivity of 4B5 with membrane-bound HER4 was identified in the clinical IHC analysis of formalin-fixed paraffin-embedded breast carcinoma cases as evidenced by the HER4 antibody clone E200.

Prediction of Crohn's disease aggression through NOD2/CARD15 gene sequencing in an Australian cohort.

AIM: To investigate the association between mutations in oligomerisation domain 2/caspase recruitment domains 15 (NOD2/CARD15) and the natural history of Crohn's disease (CD) to identify patients who would benefit from early aggressive medical intervention. METHODS: We recruited thirty consecutive unrelated CD patients with a history of ileo-caecal or small bowel resection during the period 1980-2000; Fifteen patients of these had post-operative relapse that required further surgery and fifteen did not. Full sequencing of the NOD2/CARD15 gene using dHPLC for exons 3, 5, 7, 10 and 12 and direct sequencing for exons 2, 4, 6, 8, 9 and 11 was conducted. CD patients categorized as carrying variants were anyone with at least 1 variant of the NOD2/CARD15 gene. RESULTS: About 13.3% of the cohort (four patients) carried at least one mutant allele of 3020insC of the NOD2/CARD15 gene. There were 20 males and 10 females with a mean age of 43.3 years (range 25-69 years). The mean follow up was 199.6 mo and a median of 189.5 mo. Sixteen sequence variations within the NOD2/CARD15 gene were identified, with 9 of them occurring with an allele frequency of greater than 10 %. In this study, there was a trend to suggest that patients with the 3020insC mutation have a higher frequency of operations compared to those without the mutation. Patients with the 3020insC mutation had a significantly shorter time between the diagnosis of CD and initial surgery. This study included Australian patients of ethnically heterogenous background unlike previous studies conducted in different countries. CONCLUSION: These findings suggest that patients carrying NOD2/CARD15 mutations follow a rapid and more aggressive form of Crohn's disease showing a trend for multiple surgical interventions and significantly shorter time to early surgery.

Conflict, camps and coercion: the ongoing livelihoods crisis in Darfur.

This paper presents the findings of a study commissioned by World Food Programme (WFP) in early 2006 to enhance understanding of how the conflict in Darfur has affected livelihoods and markets, and of the effects of food aid. The livelihoods of many in Darfur were devastated early on in the conflict, principally through the widespread looting or destruction of assets and highly restricted population movements, which struck at the heart of pre-conflict livelihoods. Livelihood strategies for most people are now restricted, poorly remunerated and often associated with high risk of attack. Patterns of coercion and exploitation have also become entrenched; and markets and trade, the lifeblood of Da fur's economy pre-conflict, severely disrupted. Against this backdrop the impact of food aid on livelihoods in Darfur has been overwhelmingly positive. The paper proposes a number of preconditions for investment in recovery in Darfur, and recommends ways in which livelihoods can be supported in the current context of ongoing conflict.