Broadening the repertoire of melanoma-associated T-cell epitopes

Immune therapy has provided a significant breakthrough in the treatment of metastatic melanoma. Despite the remarkable clinical efficacy and established involvement of effector CD8 T cells, the knowledge of the exact peptide-MHC complexes recognized by T cells on the tumor cell surface is limited. Many melanoma-associated T-cell epitopes have been described, but this knowledge remains largely restricted to HLA-A2, and we lack understanding of the T-cell recognition in the context of other HLA molecules. We selected six melanoma-associated antigens (MAGE-A3, NY-ESO-1, gp100, Mart1, tyrosinase and TRP-2) that are frequently recognized in patients with the aim of identifying novel T-cell epitopes restricted to HLA-A1, -A3, -A11 and -B7. Using in silico prediction and in vitro confirmation, we identified 127 MHC ligands and analyzed the T-cell responses against these ligands via the MHC multimer-based enrichment of peripheral blood from 39 melanoma patients and 10 healthy donors. To dissect the T-cell reactivity against this large peptide library, we used combinatorial-encoded MHC multimers and observed the T-cell responses against 17 different peptide-MHC complexes in the patient group and four in the healthy donor group. We confirmed the processing and presentation of HLA-A3-restricted T-cell epitopes from tyrosinase (TQYESGSMDK) and gp100 (LIYRRRLMK) and an HLA-A11-restricted T-cell epitope from gp100 (AVGATKVPR) via the cytolytic T-cell recognition of melanoma cell lines and/or K562 cells expressing the appropriate antigen and HLA molecule. We further found T-cell reactivity against two of the identified sequences among tumor-infiltrating lymphocytes from melanoma patients, suggesting a potential clinical relevance of these sequences. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00262-015-1664-x) contains supplementary material, which is available to authorized users

Stability and enzymatic studies with omeprazole: hydroxypropyl-β-cyclodextrin

The original publication is available at www.springerlink.com. A publicação original está disponível em www.springerlink.comOmeprazole (OME) exhibits low stability to light, heat and humidity. In stress conditions OME stability should improve under inclusion complex form with hydroxypropyl-b-cyclodextrin (HPbCD). Stability of OME, its physical mixture (PM) with HPbCD and OME:HPbCD inclusion complex was assessed during 60 days. The inclusion complexes were prepared by kneading and freezedrying techniques and characterized by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). A molecular modelling was also held to predict the most probable tridimensional conformation of inclusion complex OME:HPbCD. The inhibitory activity of free and complexed OME on selected enzymes, namely, papain (protease model of the proton pump) and acetylcholinesterase (enzyme present in cholinergic neurons and also involved in Alzheimer’s disease) was compared. The results obtained show that HPbCD do not protect against OME degradation, in any prepared powder, in the presence of light, heat and humidity. This may indicate that the reactive group of OME is not included in the HPbCD cavity. This fact is supported by molecular modelling data, which demonstrated that 2-pyridylmethyl group of OME is not included into the cyclodextrin cavity. In relation to enzymatic assays it was observed that free OME and OME in the binary systems showed identical inhibitory activity on papain and acethylcolinesterase, concluding that HPbCD do not affect OME activity on these two enzymes

Efficacy of Intracolonic Administration of Low-Molecular-Weight Heparin CB-01-05, Compared to Other Low-Molecular-Weight Heparins and Unfractionated Heparin, in Experimentally Induced Colitis in Rat

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Roles of the Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR pathways in controlling growth and sensitivity to therapy-implications for cancer and aging

Dysregulated signaling through the Ras/Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR pathways is often the result of genetic alterations in critical components in these pathways or upstream activators. Unrestricted cellular proliferation and decreased sensitivity to apoptotic-inducing agents are typically associated with activation of these pro-survival pathways. This review discusses the functions these pathways have in normal and neoplastic tissue growth and how they contribute to resistance to apoptotic stimuli. Crosstalk and commonly identified mutations that occur within these pathways that contribute to abnormal activation and cancer growth will also be addressed. Finally the recently described roles of these pathways in cancer stem cells, cellular senescence and aging will be evaluated. Controlling the expression of these pathways could ameliorate human health

A tale of two MADs:A case series

Background Mitral annular disjunction (MAD), consisting in a systolic separation between the posterior atrial wall-leaflet junction and the basal left ventricular wall, is a disputed imaging entity. MAD was initially associated with sudden cardiac death and ventricular arrhythmias in patients with mitral valve prolapse, whereas in more recent studies, it has been presented as a normal variant of the mitral annulus. Case summary In the present series of two cases, we show a case featuring a young woman with syncope that showed a microscopic MAD on echocardiography but, after a thorough multimodality assessment, was diagnosed with a coronary anomaly responsible for her presentation. In the second case, a young man presenting with aborted sudden cardiac death was found to have a macroscopic MAD in the context of mitral valve prolapse with numerous high-risk arrhythmic features. Discussion The need for assessing the diverse significance of MAD in the clinical and imaging context of each patient is underscored. Assessment of MAD should be complemented by other imaging and clinical parameters: the circumferential and longitudinal extent of MAD, the presence of repolarization abnormalities or ventricular arrhythmias, bi-leaflet prolapse, systolic curling, the Pickelhaube sign, left heart remodelling, and the presence of myocardial fibrosis, among others.</p

Impact of assessment-to-treatment interval and metastatic biopsy site on the predictive value of PD-L1 expression at the 1 % cut-off level in melanoma

Background: Intratumoral PD-L1 expression at the 1 % cut-off predicts clinical outcomes and may guide first-line immune checkpoint inhibitor (ICI) selection for metastatic melanoma (MM). However, the impact of the interval between PD-L1 assessment and ICI initiation and the metastatic site used for PD-L1 evaluation, remains unclear. Methods: In this nationwide cohort study we used the Danish Metastatic Melanoma Database (DAMMED) and the Danish Pathology Registry to analyze patients with MM treated with anti-PD-1 or anti-PD-1 plus anti-CTLA-4 from January 2017 to February 2024. Progression-free survival (PFS) and overall survival (OS) were analyzed using Log-rank tests and Cox regression. Results: Data from 1137 patients were analyzed. Among patients with PD-L1 assessed within 90 days of treatment (n = 964; 55.2 % PD-L1 &lt;1 %, 44.8 % PD-L1 ≥1 %), combination therapy improved outcomes in PD-L1 &lt; 1 % (PFS adjusted (a)HR 0.62; 95 % CI 0.48–0.80; p &lt; 0.001, OS aHR 0.64; 95 % CI 0.48–0.85; p = 0.002), while outcomes were comparable for PD-L1 ≥ 1 % patients (PFS aHR 0.90; 95 % CI 0.62–1.30; p = 0.57, OS aHR 0.97; 95 % CI 0.60–1.57; p = 0.89). For PD-L1 assessed &gt; 90 days prior (n = 173), this pattern was less pronounced. Among 48 paired PD-L1 assessments from the same organ, discordance occurred in 25 %. Combination therapy improved PFS for patients with PD-L1 &lt; 1 % skin/subcutaneous (aHR 0.51; 95 % CI 0.34–0.76; p &lt; 0.001) and visceral metastases (aHR 0.65; 95 % CI 0.42–1.02; p = 0.060) while this association was not evident for lymph node metastases (aHR 0.79; 95 % CI 0.48–1.29; p = 0.35). Conclusions: PD-L1 seems a reliable predictive biomarker in MM, when assessed on tissue obtained within 90 days prior to ICI initiation. Non-nodal metastatic sites appear preferable.</p