Cytokine and soluble programmed death-ligand 1 levels in serum and plasma of cancer patients treated with immunotherapy: Preanalytical and analytical considerations

AIM

To evaluate cytokine and soluble programmed death ligand-1 (sPD-L1) levels in the serum and plasma of cancer patients treated with immunotherapy, and to test different assays.

METHODS

Three Luminex xMAP assays and two ELLA microfluidic cartridges were used to screen 28 immune-related biomarkers in 38 paired serum and citrate-theophylline-adenosine-dipyridamole (CTAD) plasma samples collected from 10 advanced melanoma or non-small cell lung cancer (NSCLC) patients at different time points during immunotherapy.

RESULTS

Twenty-three of 28 biomarkers were detected both in serum and plasma by at least one of the assays, including IL-1β, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, GM-CSF, IFN-γ, TNF-α, VEGF, IP-10, MCP-1, eotaxin, fractalkine, G-CSF, IFN-α, IL-1RA, IL-13, IL-17A, MIP-1β and sPD-L1. Conversely, FGF-2 and IL-1α were not detected in both matrices; GRO-α factor and EGF were detected only in serum and MIP-1α only in plasma. sPD-L1, MCP-1, IFN-γ, IL-8, MIP-1β and VEGF were, respectively, 1.15-, 1.44-, 1.83-, 2.43-, 2.82-, 6.72-fold higher in serum, whereas IL-10, IL-4, IL-2 and IL-5 were 1.05-, 1.19-, 1.92- and 2.17-fold higher, respectively, in plasma. IP-10 levels were higher in plasma but, as well as for VEGF, the bias serum versus plasma varied depending on the assay used (IP-10: -5.7% to -145%; VEGF: 115% to 165%). No significant differences were found for the remaining nine analyzed cytokines.

CONCLUSION

The cytokine and sPD-L1 levels may differ between serum and plasma samples collected from cancer patients treated with immunotherapy, and the results obtained can be influenced by the different characteristics of the tested assays. The standardization of pre-analytical and analytical procedures is therefore needed for the future implementation of these circulating biomarkers in clinical practice.

Circulating cytokines as predictors of response to immune checkpoint inhibitors (ICIs) in patients (pts) with melanoma (Mel) and non–small cell lung cancer (NSCLC)

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Background: ICIs lead to durable response and a significant survival improvement in a limited number of advanced stage Mel and NSCLC pts. The identification of predictive circulating biomarkers could be a promising tool to optimize pts’ selection and outcome for ICIs treatment. Methods: This is a prospective real-world study enrolling advanced stage Mel and NSCLC pts referred to four Italian Centers and treated with ICIs. The primary endpoint is to verify the presence of an association between circulating cytokines (IL-1b, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, TNFα, GM-CSF) and disease control rate (DCR), progression free survival (PFS) and overall survival (OS). Pts undergo a blood collection, before every cycle for 6 cycles (T1-T6) and at tumor assessment till disease progression (PD) or for 2 years. Biomarker levels were assessed by Luminex xMAP based technology using R&D High Sensitivity kits. Each marker was categorized according to high and low levels by maximizing its discriminative ability, and the association with the outcome was tested in univariate and multiple analyses. Results: We report preliminary results on the T1-T2 blood samples from the first 78 enrolled pts (32 females/46 males; 43 Mel/35 NSCLC; median age 69 years). Serum IL-6, IL-8 and IL-10 were significantly higher at T1 and T2 in pts with PD (Kruskal-Wallis test). The median relative increase (RI) of IL-8 was 32% and 2% in pts with PD and disease control (DC), respectively (p = 0.0001). At multiple logistic analysis, IL-6 and IL-8 at T2 and the RI of IL-8 were independent factors predicting the probability of DC, with an overall accuracy of 83.8%. High levels of IL-6 and IL-8 at T2 were significantly associated with a low probability of DC (OR = 0.13, 95%CI: 0.03-0.52 and OR = 0.09, 95%CI: 0.02-0.37, respectively), and the RI showed a significantly lower probability of DC (OR = 0.14, 95%CI: 0.02-0.58). With a median follow-up of 10.6 months (m), mPFS and mOS were 5.8 m, 95%CI: 2.3-7.4 and 8.3 m, 95%CI: 4.0-13.8 for NSCLC; 6.9 m, 95%CI: 2.8-15.9 and 12.6 m, 95%CI: 4.7-NE for Mel pts, respectively. In the multiple Cox model, elevated IL-6 and IL-8 at T1 (HR = 3.03, 95%CI: 1.55-6.37, HR = 2.86, 95%CI: 1.46-5.63), elevated IL-10 at T2 (HR = 2.86, 95%CI: 1.39-5.94), and a RI of IL-8 (HR = 4.22, 95%CI: 1.85-11.21) remained significantly associated with a worse PFS. Higher levels of IL-6 (HR = 3.85, 95%CI: 1.13-20.0) and IL-8 (HR = 4.29, 95%CI: 1.98-9.83) at T2 and a RI of IL-8 (HR = 3.06, 95%CI: 1.43-6.72) remained significantly associated with a worse OS. Conclusions: High serum levels of IL-8 and IL-6 at T2 of ICI, combined with an increase of IL-8 from baseline, are strong predictors of PD, PFS, OS, in pts with advanced Mel and NSCLC. The role of the other cytokines tested, their time fluctuations and associations with clinical prognostic factors, gender, and immuno-related adverse events will be presented at the meeting.

Chitosan-Coated Nanoparticles: Effect of Chitosan Molecular Weight on Nasal Transmucosal Delivery

Drug delivery to the brain represents a challenge, especially in the therapy of central nervous system malignancies. Simvastatin (SVT), as with other statins, has shown potential anticancer properties that are difficult to exploit in the central nervous system (CNS). In the present work the physico⁻chemical, mucoadhesive, and permeability-enhancing properties of simvastatin-loaded poly-ε-caprolactone nanocapsules coated with chitosan for nose-to-brain administration were investigated. Lipid-core nanocapsules coated with chitosan (LNCchit) of different molecular weight (MW) were prepared by a novel one-pot technique, and characterized for particle size, surface charge, particle number density, morphology, drug encapsulation efficiency, interaction between surface nanocapsules with mucin, drug release, and permeability across two nasal mucosa models. Results show that all formulations presented adequate particle sizes (below 220 nm), positive surface charge, narrow droplet size distribution (PDI < 0.2), and high encapsulation efficiency. Nanocapsules presented controlled drug release and mucoadhesive properties that are dependent on the MW of the coating chitosan. The results of permeation across the RPMI 2650 human nasal cell line evidenced that LNCchit increased the permeation of SVT. In particular, the amount of SVT that permeated after 4 hr for nanocapsules coated with low-MW chitosan, high-MW chitosan, and control SVT was 13.9 ± 0.8 μg, 9.2 ± 1.2 µg, and 1.4 ± 0.2 µg, respectively. These results were confirmed by SVT ex vivo permeation across rabbit nasal mucosa. This study highlighted the suitability of LNCchit as a promising strategy for the administration of simvastatin for a nose-to-brain approach for the therapy of brain tumors.

Anti-inflammatory flurbiprofen nasal powders for nose-to-brain delivery in Alzheimer's disease

Neuroinflammation occurs in the early stages of Alzheimer's disease (AD). Thus, anti-inflammatory drugs in this asymptomatic initial phase could slow down AD progression, provided they enter the brain. Direct nose-to-brain drug transport occurs along olfactory or trigeminal nerves, bypassing the blood-brain barrier. Nasal administration may enable the drug to access the brain. Here, flurbiprofen powders for nose-to-brain drug transport in early AD-related neuroinflammation were studied. Their target product profile contemplates drug powder deposition in the nasal cavity, prompt dissolution in the mucosal fluid and attainment of saturation concentration to maximise diffusion in the tissue. Aiming to increase drug disposition into brain, poorly soluble flurbiprofen requires the construction of nasal powder microparticles actively deposited in nose for prompt drug release. Two groups of powders were formulated, composed of flurbiprofen acid or flurbiprofen sodium salt. Two spray dryer apparatuses, differing for spray and drying mechanisms, and particle collection, were applied to impact on the characteristics of the microparticulate powders. Flurbiprofen sodium nasal powders disclosed prompt dissolution and fast ex vivo transport across rabbit nasal mucosa, superior to the acid form, in particular when the powder was prepared using the Nano B-90 spray dryer at the lowest drying air temperature.

Chitosan coated human serum albumin nanoparticles: A promising strategy for nose-to-brain drug delivery

The aim of the present study was the development of human serum albumin nanoparticles (HSA NPs) as nose-to-brain carrier. To strengthen, the efficacy of nanoparticles as drug delivery system, the influence of chitosan (CS) coating on the performance of HSA NPs was investigated for nasal application. HSA NPs were prepared by desolvation technique. CS coating was obtained adding the CS solution to HSA NPs. The mean particle sizes was 241 ± 18 nm and 261 ± 8 nm and the ζ-potential was -47 ± 3 mV and + 45 ± 1 mV for HSA NPs and CS-HSA NPs, respectively. The optimized formulations showed excellent stability upon storage both as suspension and as freeze-dried product after 3 months. The mucoadhesion properties were assessed by turbidimetric and indirect method. NPs were loaded with sulforhodamine B sodium salt as model drug and the effect of CS coating was investigated performing release studies, permeation and uptake experiments using Caco-2 and hCMEC/D3 cells as model of the nasal epithelium and blood-brain barrier, respectively. Furthermore, ex vivo diffusion experiments have been carried out using rabbit nasal mucosa. Finally, the ability of the formulations to reversibly open tight and gap junctions was explored by western blotting and RT-PCR analyzing in both Caco-2 and hCMEC/D3 cells.

Opportunity and challenges of nasal powders: Drug formulation and delivery

In the field of nasal drug delivery, among the preparations defined by the European Pharmacopoeia, nasal powders facilitate the formulation of poorly water-soluble active compounds. They often display a simple composition in excipients (if any), allow for the administration of larger drug doses and enhance drug diffusion and absorption across the mucosa, improving bioavailability compared to nasal liquids. Despite the positive features, however, nasal products in this form still struggle to enter the market: the few available on the market are Onzetra Xsail® (sumatriptan) for migraine relief and, for the treatment of rhinitis, Rhinocort® Turbuhaler® (budesonide), Teijin Rhinocort® (beclomethasone dipropionate) and Erizas® (dexamethasone cipecilate). Hence, this review tries to understand why nasal powder formulations are still less common than liquid ones by analyzing whether this depends on the lack of (i) real evidence of superior therapeutic benefit of powders, (ii) therapeutic and/or commercial interest, (iii) efficient manufacturing methods or (iv) availability of suitable and affordable delivery devices. To this purpose, the reader's attention will be guided through nasal powder formulation strategies and manufacturing techniques, eventually giving up-to-date evidences of therapeutic efficacy in vivo. Advancements in the technology of insufflation devices will also be provided as nasal drug products are typical drug-device combinations.

Neurotensin: A role in substance use disorder?

Neurotensin is a tridecapeptide originally identified in extracts of bovine hypothalamus. This peptide has a close anatomical and functional relationship with the mesocorticolimbic and nigrostriatal dopamine system. Neural circuits containing neurotensin were originally proposed to play a role in the mechanism of action of antipsychotic agents. Additionally, neurotensin-containing pathways were demonstrated to mediate some of the rewarding and/or sensitizing properties of drugs of abuse.This review attempts to contribute to the understanding of the role of neurotensin and its receptors in drug abuse. In particular, we will summarize the potential relevance of neurotensin, its related compounds and neurotensin receptors in substance use disorders, with a focus on the preclinical research.