Expression of 4-1BB and its ligand on blasts correlates with prognosis of patients with AML.

Costimulatory ligands (COLs) and their receptors (COR) regulate immune reactions and cellular survival and might be relevant in acute myeloid leukemia (AML). This study evaluated the clinical relevance of 4-1BBL, glucocorticoid-induced TNFR-related protein (GITR) and ligand (GITRL), CD80, and CD86 in case of expression on AML blasts. 98 patients were evaluated at initial diagnosis. Immunophenotypically evaluated specific fluorescence index (SFI) levels of COR and COL on blasts were correlated with morphological, cytogenetic, and several prognostic parameters. Significantly higher COR expression was seen in monocytic versus non-monocytic AML subtypes; GITR, p=0.05; GITRL, p=0.005; CD86, p=0.001). Cut-off values for two COR and their ligands were evaluated: cases presenting with 4-1BB values above cut-off 1.2 SFI levels correlated (tendentially) significantly with a higher probability for disease-free survival (DFS, p=0.06) and a favorable HR of 0.2; p=0.04 for relapse. HR for death was also significantly lower in this group (0.12; p=0.04). In contrast, a lower probability for DFS and overall survival was seen in cases with 4-1BBL expression above 2.2 SFI levels (p=0.08 and p=0.09). In addition, multivariate analysis showed a significantly higher probability of death in this group (HR 10.3, p=0.04). Expression of CD80 and CD86 did not show significant prognostic relevance. On initial diagnosis, 4-1BB and 4-1BBL qualify as markers for prediction of patients' course and represent a valuable screening target for patients with AML at initial diagnosis.

Expression of RANK-L and in part of PD-1 on blasts in patients with acute myeloid leukemia correlates with prognosis.

BACKGROUND: Co-stimulatory receptor (COR) and ligand (COL) expression on immune effectors are known to be relevant for immunological interactions and might be of prognostic relevance if expressed on acute myeloid leukemia (AML) blasts as reported for receptors of the tumor necrosis factor receptor family. AIM AND METHODS: Antigen expression profiling of COR (RANK, PD-1), COL (RANK-L, PD-1L), and HLA-ABC-antigens on blasts from 90 AML-patients at first diagnosis was performed by flow cytometry (SFI-Level characterization) and findings were correlated with clinical parameters. RESULTS: RANK expression was higher in immature compared to mature FAB groups (P = 0.08). As a monocytic marker, we identified HLA-ABC (P = 0.07). Prognostic analysis revealed a higher probability of overall survival in cases with lower RANK-L expression (<1.6 and ≥1.6, 15.6 vs. 12.2 months, P = 0.008, hazard ratio 0.36, P = 0.008). No significant impact of PD-1/L expression for patients'(pts) survival was seen but a correlation of PD-1 with a secondary AML (P = 0.03). Prolonged disease-free survival however correlated with higher PD-1 expression (≥1.1 vs. <1.1, 31.4 vs. 12.7 months; P = 0.03). CONCLUSION: Our study revealed that RANK-L is a promising marker to forecast pts' prognosis in AML. Immune checkpoint receptor PD-1/L as well as RANK and HLA-ABC did not show an impact on pts' survival.

Death Receptor Expression on Blasts in AML Is Associated with Unfavorable Prognosis.

BACKGROUND: Tumor necrosis factor (TNF) receptor family members play a key role in the regulation of biological functions such as differentiation, proliferation and apoptosis of various cell types. MATERIALS AND METHODS: We studied co-expression profiles of death receptors from the TNF family [TNF-related apoptosis-inducing ligand receptor (TRAILR) 1 to 3, TNF receptor 1 (TNFR1) and FAS receptor (FAS)] on peripheral blood blasts from 46 patients with acute myeloid leukemia (AML) at first diagnosis by flow cytometry and correlated the obtained specific fluorescence indices (SFI) with morphological, cytogenetic and clinical parameters. RESULTS: We found that the expression of TRAILR2 and R3 was significantly increased in unfavorable risk groups, according to the National Comprehensive Cancer Network. Additionally, cut-off analyses for TRAILR2 and TNFR1 showed significantly shorter overall survival, earlier disease onset, higher proportions of cases with unfavorable prognosis and higher probability of relapse when SFIs were above the established cut-off. CONCLUSION: We demonstrate that high co-expression of death receptors on blasts is an independent predictor of poor prognosis in AML.

Urine and serum concentrations of Cytokeratin 19 in preeclampsia.

OBJECTIVE: To evaluate the usefulness of Cytokeratin 19 as biomarker for the diagnosis of preeclampsia. STUDY DESIGN: Cytokeratin 19 protein fragment CYFRA 21-1 was measured by means of electrochemiluminescence immunoassays in urine and serum samples of 32 women with preeclampsia and 32 samples of normotensive healthy singleton pregnancies at random, matched for gestational age, as controls. RESULTS: The median serum concentrations of CYFRA 21-1 in controls and women with preeclampsia were 2.4 (range 1.3-6.6)ng/mL and 4.4 (range 2.1-16.2)ng/mL, respectively (p<0.001). The median urine concentrations of CYFRA 21-1 in controls and women with preeclampsia were 13.7 (range 0.7-441.4)ng/mL and 11.8 (range 1.5-338.6)ng/mL, respectively (p=0.629). Calculation of a ROC curve to study the use of serum CYFRA 21-1 concentration as a predictor of preeclampsia revealed cut-off points with the highest sum of specificity and sensitivity of 3.2ng/mL, leading to specificity of 75% and sensitivity of 84%. A similar curve calculated for CYFRA 21-1 in urine showed an area under the curve of 0.536 meaning no predictive power. The correlation between urinary excretion of protein in 24h and serum concentrations of CYFRA 21-1 in the case group was r=0.26, which is not significant (p=0.258). The correlation between proteinuria and urine values of CYFRA 21-1 was r=0.10, which also is not significant (p=0.666). CONCLUSION: Serum levels of Cytokeratin 19 fragment are increased in women with preeclampsia. However this does not result in a significant difference in CYFRA 21-1 levels in maternal urine. Thus Cytokeratin 19 fragment may prove to be a valuable biomarker for preeclampsia in serum but not urine. We propose further longitudinal studies to investigate the role of Cytokeratin 19 in maternal serum of women with preeclampsia.

Preeclampsia - a risk factor for osteoporosis? Analysis of maternal Sclerostin levels and markers of bone turnover in patients with pre-eclampsia.

INTRODUCTION: The role of preeclampsia (PE) in affecting bone metabolism could not be clarified in the past years. Recently Sclerostin, a new marker of bone metabolism which is known to have an inhibitory effect on bone formation causing osteoporosis, was discovered. OBJECTIVE: To investigate serum levels of Sclerostin and markers of bone turnover in women with normotensive pregnancies and pregnancies complicated by PE. METHODS: In this prospective study we enrolled 22 women with PE and 22 healthy pregnant women to observe serum levels of carboxyterminal propeptide of type I collagen (PICP), cross-linked carboxyl terminal telopeptide of the type I collagen (ICTP), calcium, phosphate, 25-hydroxyvitamin D and parathyroid hormone. In 16 preeclamptic and 16 healthy pregnant women, serum Sclerostin levels were analyzed. RESULTS: Serum levels of Sclerostin (mean ± standard deviation: healthy 10.5 ± 8.1 pmol/l versus PE 11.5 ± 9.4 pmol/l, p = 0.768), ICTP (healthy 0.3 ± 0.2 ng/ml versus PE 0.4 ± 0.1 ng/ml, p = 0.462), PICP (healthy 59.9 ± 49.9 ng/ml versus PE 89.0 ± 62.0 ng/ml, p = 0.094), phosphate (healthy 1.1 ± 0.2 mmol/l versus PE 1.2 ± 0.4 mmol/l, p = 0.162) and parathyroid hormone (healthy 26.9 ± 14 pg/ml versus PE 35.3 ± 17.6 pg/ml, p = 0.08) showed no significant differences between the groups. Significantly lower serum calcium (healthy 2.3 ± 0.1 mmol/l versus PE 2.2 ± 0.2 mmol/l, p < 0.005) and serum 25-Hydroxyvitamin D (healthy 39.3 ± 16.7 nmol/l versus PE 23.9 ± 16.9 nmol/l, p < 0.005) were observed in preeclamptic women. CONCLUSION: Pregnancies complicated by PE show no signs of high bone turnover and may not lead to a higher risk of osteoporosis in later life.

The PTAP sequence within the p6 domain of human immunodeficiency virus type 1 Gag regulates its ubiquitination and MHC class I antigen presentation.

Endogenous peptides presented by MHC class I (MHC-I) molecules are mostly derived from de novo synthesized, erroneous proteins, so-called defective ribosomal products (DRiPs), which are rapidly degraded via the ubiquitin-proteasome pathway. We have previously shown that the HIV-1 Gag protein represents a bona fide substrate for the DRiP pathway and that the amount of Gag-DRiPs can be enhanced by the introduction of an N-end rule degradation signal, leading to increased MHC-I presentation and immunogenicity of Gag. Based on these findings, we sought to identify a naturally occurring sequence motif within Gag that regulates its entry into the DRiP pathway. As the PTAP late assembly domain motif in the C-terminal p6 domain of Gag has been shown to negatively regulate the ubiquitination of Gag, we analyzed the correlation between ubiquitination and MHC-I presentation of PTAP-deficient Gag. Intriguingly, mutation of PTAP not only reduces the release of virus-like particles, but also increases ubiquitination of Gag and, consistently, enhances MHC-I presentation of a Gag-derived epitope. Although the half-life of the PTAP mutant was only mildly reduced, the entry into the DRiP pathway was significantly increased, as demonstrated by short-term pulse-chase analyses under proteasome inhibition. Collectively, these results indicate that, besides driving virus release, the PTAP motif regulates the entry of Gag into the DRiP pathway and, thus, into the MHC-I pathway. Although there are no naturally occurring PTAP mutants of HIV-1, mutations of PTAP might enhance the immunogenicity of Gag and, thus, be considered for the improvement of vaccine development.