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Tamoxifen-induced radioresistance, reported in vitro, might pose a problem for patients who receive neoadjuvant tamoxifen treatment and subsequently receive radiotherapy after surgery. Previous studies suggested that DNA damage repair or cell cycle genes are involved, and could therefore be targeted to preclude the occurrence of cross-resistance. We aimed to characterize the observed cross-resistance by investigating gene expression of DNA damage repair genes and cell cycle genes in estrogen receptor-positive MCF-7 breast cancer cells that were cultured to tamoxifen resistance. RNA sequencing was performed, and expression of genes characteristic for several DNA damage repair pathways was investigated, as well as expression of genes involved in different phases of the cell cycle. The association of differentially expressed genes with outcome after radiotherapy was assessed in silico in a large breast cancer cohort. None of the DNA damage repair pathways showed differential gene expression in tamoxifen-resistant cells compared to wild-type cells. Two DNA damage repair genes were more than two times upregulated (NEIL1and EME2), and three DNA damage repair genes were more than two times downregulated (PCNA, BRIP1, and BARD1). However, these were not associated with outcome after radiotherapy in the TCGA breast cancer cohort. Genes involved in G1, G1/S, G2, and G2/M phases were lower expressed in tamoxifen-resistant cells compared to wild-type cells. Individual genes that were more than two times upregulated (MAPK13) or downregulated (E2F2, CKS2, GINS2, PCNA, MCM5, and EIF5A2) were not associated with response to radiotherapy in the patient cohort investigated. We assessed the expression of DNA damage repair genes and cell cycle genes in tamoxifen-resistant breast cancer cells. Though several genes in both pathways were differentially expressed, these could not explain the cross-resistance for irradiation in these cells, since no association to response to radiotherapy in the TCGA breast cancer cohort was found.

This review provides the reader with current insights on testicular adrenal rest tumors (TARTs), a complication in male patients with congenital adrenal hyperplasia (CAH). In recent studies, an overall TART prevalence of 40% (range, 14% to 89%) in classic patients with CAH is found. Reported differences are mainly caused by the method of detection and the selected patient population. Biochemically, histologically, and molecularly, TARTs exhibit particular adrenal characteristics and were therefore thought to originate from aberrant adrenal cells. More recently, TARTs have been found to also exhibit testicular characteristics. This has led to the hypothesis of pluripotent cells as the origin of TARTs. High concentrations of ACTH could cause hyperplasia of these pluripotent cells, as TARTs appear to be associated with poor hormonal control with concomitant elevated ACTH. Unfortunately, as yet there are no methods to prevent the development of TARTs, nor are there guidelines to treat patients with TARTs. Intensified glucocorticoid treatment could improve fertility status in some cases, although studies report contradicting results. TARTs can also lead to irreversible testicular damage, and therefore semen cryopreservation could be offered to patients with TARTs. Further research should focus on the etiology and pharmacological treatment to prevent TART development or to treat TARTs and improve the fertility status of patients with TARTs.

Testicular adrenal rest tumors (TARTs), commonly occurring in males with congenital adrenal hyperplasia, may arise from chronic stimulation of adrenocorticotropic hormone (ACTH)–sensitive cells in the testes. It is not yet established whether the human fetal testis (HFT) is responsive to ACTH. To investigate this, we cultured HFT tissue with and without ACTH for up to 5 days, and quantified adrenal steroid hormones and expression of adrenal steroidogenic enzymes. Fetal testis and adrenal tissue produced high levels of testosterone and cortisol, respectively, indicating viability. In contrast to fetal adrenal tissues, the expression of ACTH receptor MC2Rwas either absent or expressed at extremely low levels in ex vivo HFT tissue and no clear response to ACTH in gene expression or steroid hormone production was observed. Altogether, this study suggests that the HFT is unresponsive to ACTH, which would indicate that a TART does not arise from fetal testicular cells chronically exposed to ACTH in utero.

Testicular adrenal rest tumours (TARTs) are benign adrenal-like testicular tumours that frequently occur in male patients with congenital adrenal hyperplasia. Recently, GATA transcription factors have been linked to the development of TARTs in mice. The aim of our study was to determine GATA expression in human TARTs and other steroidogenic tissues. We determined GATA expression in TARTs (n= 16), Leydig cell tumours (LCTs; n= 7), adrenal (foetal (n= 6) + adult (n= 10)) and testis (foetal (n= 13) + adult (n= 8)). We found testis-like GATA4, and adrenal-like GATA3and GATA6gene expressions by qPCR in human TARTs, indicating mixed testicular and adrenal characteristics of TARTs. Currently, no marker is available to discriminate TARTs from LCTs, leading to misdiagnosis and incorrect treatment. GATA3and GATA6mRNAs exhibited excellent discriminative power (area under the curve of 0.908 and 0.816, respectively), while immunohistochemistry did not. GATA genes contain several CREB-binding sites and incubation with 0.1 mM dibutyryl cAMP for 4 h stimulated GATA3, GATA4and GATA6expressions in a human foetal testis cell line (hs181.tes). Incubation of adrenocortical cells (H295RA) with ACTH, however, did not induce GATAexpression in vitro. Although ACTH did not dysregulate GATAexpression in the only human ACTH-sensitive in vitromodel available, our results do suggest that aberrant expression of GATA transcription factors in human TARTs might be involved in TART formation.

Recurrence of hypercortisolism in patients after bilateral adrenalectomy for Cushing disease is extremely rare.

The distinction between unilateral aldosterone-producing adenoma or bilateral adrenal hyperplasia as causes of primary aldosteronism is usually made by adrenal CT or by adrenal vein sampling (AVS). Whether CT or AVS represents the best test for diagnosis remains unknown. We aimed to compare the outcome of CT-based management with AVS-based management for patients with primary aldosteronism.

We recently reported on the development of a 4-protein-based classifier (PDCD4, CGN, G3BP2, and OCIAD1) capable of predicting outcome to tamoxifen treatment in recurrent, estrogen-receptor-positive breast cancer based on high-resolution MS data. A precise and high-throughput assay to measure these proteins in a multiplexed, targeted fashion would be favorable to measure large numbers of patient samples to move these findings toward a clinical setting. By coupling immunoprecipitation to multiple reaction monitoring (MRM) MS and stable isotope dilution, we developed a high-precision assay to measure the 4-protein signature in 38 primary breast cancer whole tissue lysates (WTLs). Furthermore, we evaluated the presence and patient stratification capabilities of our signature in an independent set of 24 matched (pre- and post-therapy) sera. We compared the performance of immuno-MRM (iMRM) with direct MRM in the absence of fractionation and shotgun proteomics in combination with label-free quantification (LFQ) on both WTL and laser capture microdissected (LCM) tissues. Measurement of the 4-proteins by iMRM showed not only higher accuracy in measuring proteotypic peptides (Spearman r: 0.74 to 0.93) when compared with MRM (Spearman r: 0.0 to 0.76) but also significantly discriminated patient groups based on treatment outcome (hazard ratio [HR]: 10.96; 95% confidence interval [CI]: 4.33 to 27.76; Log-rank P< 0.001) when compared with LCM (HR: 2.85; 95% CI: 1.24 to 6.54; Log-rank P= 0.013) and WTL (HR: 1.16; 95% CI: 0.57 to 2.33; Log-rank P= 0.680) LFQ-based predictors. Serum sample analysis by iMRM confirmed the detection of the four proteins in these samples. We hereby report that iMRM outperformed regular MRM, confirmed our previous high-resolution MS results in tumor tissues, and has shown that the 4-protein signature is measurable in serum samples.

The use of therapeutic monoclonal antibodies for clinical purposes has significantly increased in recent years, and so has the need to monitor antibody concentrations. This may be achieved using the well-established enzyme linked immunoassay (ELISA) methods; however, these assays are subject to a variety of interferences.

Bevacizumab and cetuximab are approved for the treatment of cancer. However, in advanced colorectal cancer, addition of cetuximab to chemotherapy with bevacizumab did not improve survival. The reason for the lack of activity remains unclear. The aim of this study was to determine the effect of cetuximab on VEGF expression and targeting of bevacizumab to the tumor. Mice with subcutaneous SUM149 or WiDr xenografts were treated with cetuximab, bevacizumab, or a combination of the two. Before the start of cetuximab treatment and after 7 and 21 days of treatment, the uptake of radiolabeled bevacizumab in the tumor was measured by immunoSPECT/CT. Tumor growth of SUM149 xenografts was significantly inhibited by cetuximab, bevacizumab, or their combination, whereas growth of WiDr xenografts was not affected. Cetuximab caused a significant reduction of bevacizumab uptake in SUM149 xenografts, whereas tumor-to-blood ratios in mice with WiDr xenografts did not change. Biodistribution studies with an irrelevant antibody in the SUM149 model also showed significantly reduced tumor-to-blood ratios. Cetuximab treatment did not decrease VEGF expression. Without decreasing VEGF levels, cetuximab reduces tumor targeting of bevacizumab. This could, at least partly, explain why the combination of bevacizumab and cetuximab does not result in improved therapeutic efficacy.

Macrophage migration inhibitory factor (MIF), a protein secreted by immune cells and the pituitary gland, may be associated with coronary artery disease (CAD) and the mental state of coronary patients. The first origin of MIF suggests positive, the second negative associations. The aim of this study was to explore the direction of the association of MIF with CAD and of MIF with exhaustion, if any.

Microdialysis is a sampling method that permits measurement of hormones, drugs, and other lower molecular weight compounds present in interstitial fluid. We developed a straightforward mathematical model that predicts a linear relationship between the reciprocal dialysate concentration of the analyte from the interstitium and perfusion rate, permitting estimation of the interstitial concentration by extrapolation to zero perfusion rate. Conversely, linearity between the reciprocal dialysate concentration of internal standard added to the perfusion medium (retrodialysis), and the reciprocal perfusion rate, is predicted. In nine healthy volunteers, interstitial norepinephrine (NE) was estimated by NE measurements in microdialysates obtained from skeletal muscle and adipose subcutaneous tissue, using sodium salicylate (Sal) in the perfusion buffer as internal standard, at perfusion rates of 2 and 5 mul/min. Comparison with microdialysis in vitro by immersing the probe in a large volume of buffer containing NE showed that the in vivo (retro)recovery of NE and Sal is almost exclusively determined by transport of NE through the interstitial space toward and Sal from the membrane and that membrane permeability itself plays a negligible role. This was supported by the observation that applying lower body negative pressure, a measure that is unlikely to affect membrane permeability, resulted in a significant (p < 0.05) decrease of Sal retrorecovery from muscle interstitium. This validated new model significantly adds insight into the factors determining recovery of substances from the interstitium in microdialysis and provides a simpler alternative to previous approaches for estimation of interstitial concentrations.

Objective: Human chorionic gonadotropin (hCG) is widely used in the management of hydatidiform mole and persistent trophoblastic disease (PTD). Predicting PTD after molar pregnancy might be beneficial since prophylactic chemotherapy reduces the incidence of PTD.Design: A retrospective study based on blood specimens collected in the Dutch Registry for Hydatidiform Moles. A group of 165 patients with complete moles (of which 43 had PTD) and 39 patients with partial moles (of which 7 had PTD) were compared with 27 pregnant women with uneventful pregnancy.Methods: Serum samples from patients with hydatidiform mole with or without PTD were assayed using specific (radio) immunoassays for free α-subunit (hCGα), free β-subunit (hCGβ) and ‘total’ hCG (hCG + hCGβ). In addition, we calculated the ratios hCGα/hCG + hCGβ, hCGβ/hCG + hCGβ, and hCGα/hCGβ. Specificity and sensitivity were calculated and paired in receiver-operating characteristic (ROC) curve analysis, resulting in areas under the curves (AUCs).Results: hCGβ, hCGβ/hCG + hCGβ and hCGα/hCGβ show AUCs ranging between 0.922 and 0.999 and, therefore, are excellent diagnostic tests to distinguish complete and partial moles from normal pregnancy. To distinguish partial from complete moles the analytes hCGβ, hCG + hCGβ and the ratio hCGα/hCGβ have AUCs between 0.7 and 0.8. Although hCGα, hCGβ and hCG + hCGβ concentrations are significantly elevated in patients who will develop PTD compared with patients with spontaneous regression after evacuation of their moles, in predicting PTD, these analytes and parameters have AUCs <0.7.Conclusions: Distinction between hydatidiform mole and normal pregnancy is best shown by a single blood specimen with hCGβ, but hCGβ/hCG + hCGβ and hCGα/hCGβ are also excellent diagnostic parameters. To predict PTD, hCGα, hCGβ, hCG + hCGβ and hCGα/hCGβ are moderately accurate tests, although they are not accurate enough to justify prophylactic chemotherapy treatment for prevention of PTD.

The ability of a solid tumor to grow and metastasize has a significant dependence on protease systems, such as the plasminogen activation system. The plasminogen activation system includes the urokinase‐type plasminogen activator (uPA) and plasminogen activator inhibitor type 1 (PAI‐1), among other molecules. Both uPA and PAI‐1 are established prognostic factors for patients with breast carcinoma. In the current study, the authors investigated whether the complex of uPA with PAI‐1 is also associated with the natural course of this malignancy.Cytosolic levels of uPA, PAI‐1, and the uPA:PAI‐1 complex were measured in tumor tissue from 576 patients with lymph node–negative invasive breast carcinoma using quantitative enzyme‐linked immunosorbent assays. Patients did not receive adjuvant systemic therapy, and the median follow‐up duration was 61 months (range, 2–187 months) after primary diagnosis. Correlations with well known clinicopathologic factors were assessed, and univariate and multivariate survival analyses were performed.uPA:PAI‐1 complex levels were positively associated with adverse histologic grade and inversely correlated with estrogen and progesterone receptor status. On univariate analysis, increased levels of the uPA:PAI‐1 complex were found to be associated with reduced recurrence‐free survival (RFS) and overall survival (OS) rates. On multivariate analysis, uPA:PAI‐1 complex levels were found to be an independent predictor of OS (P = 0.039), but not RFS (P = 0.240). When uPA and PAI‐1 levels were not included in the multivariate analysis, uPA:PAI‐1 complex levels became a significant predictor of both RFS and OS (P = 0.029 and P = 0.007, respectively).The results of the current study demonstrate that uPA:PAI‐1 complex levels have prognostic value on univariate analysis. In addition, increased uPA:PAI‐1 complex levels were significantly associated with poor OS on multivariate analysis. Increased uPA:PAI‐1 complex levels were also significantly associated with reduced RFS rates after the exclusion of uPA and PAI‐1 levels from the multivariate analysis model. Cancer 2004. © 2004 American Cancer Society.

The aim of this investigation was to assess the bioavailability and pharmacokinetics of oxytocin in six male subjects after a sublingual dose of 400 int. units (684 μg) and after an intravenous dose of 1 int. unit (1·71 μg).After intravenous administration, the pharmacokinetic profile could be described with a two-compartment model. The distribution half-life was 0·049 ± 0·016 h, the elimination half-life was 0·33 ± 0·23 h, the total body clearance was 67·1 ± 13·4 Lh−1and the volume of distribution was 33·2 ± 28·1 L. After sublingual administration, a poor bioavailability with a 10-fold variation between 0·007 and 0·07% was observed. The pharmacokinetic profile could be described with a one-compartment model. The lag time was subject-dependent and ranged between 0·12 and 0·30 h (40% CV). The absorption half-life was 0·45 ± 0·29 h, and the apparent elimination half-life 0·69 ± 0·26 h.This study showed a very poor and interindividual variability in bioavailability. The sublingual route of administration with its ‘long’ lag time and ‘long’ absorption half-life would not seem a reliable route for accurate high dosing for immediate prevention of post-partum haemorrhage.