iTRAQ-based quantitative proteomics reveals biomarkers/pathways in psoriasis that can predict the efficacy of methotrexate

BACKGROUND

Methotrexate (MTX) is the first-line medicine to treat psoriasis. So far, there has been less research on protein biomarkers to predict its efficacy by the proteomic technique.

OBJECTIVES

To evaluate differentially expressed proteins in peripheral mononuclear cells (PBMCs) between good responders (GRs) and non-responders (NRs) after MTX treatment, compared with normal controls (NCs).

METHODS

We quantified protein expression of PBMCs with 4 GRs and 4 NRs to MTX and 4 NCs by isobaric tags for relative and absolute quantification (iTRAQ), analyzing and identifying proteins related to efficacy of MTX in 18 psoriatic patients.

RESULTS

A total of 3,177 proteins had quantitative information, and 403 differentially expressed proteins (fold change ≥ 1.2, p < .05) were identified. Compared to NCs, upregulated proteins (ANXA6, RPS27A, EZR, XRCC6), participating in the activation of NF-κB, the JAK-STAT pathway, and neutrophil degranulation were detected in GRs. The proteins (GPV, FN1, STOM), involving platelet activation, signaling and aggregation as well as neutrophil degranulation were significantly downregulated in GRs. These proteins returned to normal levels after MTX treatment. Furthermore, Western blotting identified the expression of ANXA6 and STAT1 in PBMCs, which were significantly downregulated in GRs, but not in NRs.

CONCLUSIONS

We identified seven differentially expressed and regulated proteins (ANXA6, GPV, FN1, XRCC6, STOM, RPS27A, and EZR) as biomarkers to predict MTX efficacy in NF-κB signaling, JAK-STAT pathways, neutrophil degranulation, platelet activation, signaling and aggregation.

Improving patient outcomes in psoriasis: strategies to ensure treatment adherence

Psoriasis is a frequent inflammatory disease with a chronic and relapsing course. Therefore, patients with psoriasis are likely to undergo different treatments for long periods of time. Traditionally, therapies used in psoriasis have been associated with poor levels of adherence due to the complexity of the regimens and the poor results obtained with the topical therapies. These poor outcomes are associated with high levels of frustration and anxiety, which decrease adherence and worsen the disease. With the recent introduction of highly efficacious biologic therapies, patients can achieve very good and prolonged responses. However, most patients with psoriasis have mild disease and may be treated with skin-directed therapies. Therefore, it is important to develop strategies to improve adherence in order to achieve better outcomes, and to improve the overall quality of life. Hence, acknowledging the causes of nonadherence is crucial for implementing these strategies. In this summary, we review the causes of nonadherence, and we provide behavioral strategies in order to improve adherence and, ultimately, the outcome of patients with psoriasis.

Leukocyte-derived koebnerisin (S100A15) and psoriasin (S100A7) are systemic mediators of inflammation in psoriasis

BACKGROUND

Psoriasis is a systemic immune-mediated chronic inflammatory disease. In the skin, the antimicrobial proteins koebnerisin (S100A15) and psoriasin (S100A7) are overexpressed in the epidermis of psoriatic lesions and mediate inflammation as chemoattractants for immune cells. Their role for systemic inflammation in circulating leukocytes is unknown.

OBJECTIVE

The aim of the study was to identify circulating leukocyte populations as a source of koebnerisin and psoriasin. Further, immune-stimulatory effects of these S100A proteins on circulating leukocytes were evaluated and their role as therapeutic response markers in patients with psoriasis was analyzed upon UVB treatment.

METHODS

The expression and production of koebnerisin and psoriasin by leukocytes were assessed by quantitative real-time PCR (qRT-PCR) and immunoblotting. The S100A protein mediated regulation of proinflammatory cytokines by peripheral blood mononuclear cells (PBMCs) was measured with qRT-PCR and cytometric bead assay.

RESULTS

We identified circulating leukocytes as novel sources of koebnerisin (S100A15) and psoriasin (S100A7). Circulating leukocytes (PBMCs) of patients with psoriasis produced increased levels of koebnerisin and psoriasin compared to healthy individuals. Both S100A proteins further acted as 'alarmins' on PBMC to induce proinflammatory cytokines implicated in the pathogenesis of psoriasis, such as IL-1β, TNF-α, IL-6 and IL-8. Koebnerisin levels were suppressed in PBMC of psoriatic patients when effectively treated with narrow-band UVB.

CONCLUSIONS

Data suggest that koebnerisin and psoriasin are systemic pro-inflammatory mediators and koebnerisin acts as a therapeutic response marker in psoriasis.

Systemic methotrexate for the treatment of psoriasis

In the era of biologic therapies, methotrexate (MTX), a classic immunomodulator, is still the cornerstone of systemic treatment of psoriasis. MTX has been used for many years, achieving good responses with a good safety profile. However, only a few randomized clinical trials have been performed involving MTX, and most of the current evidence comes from pivotal studies of biologic drugs. The aim of this article is to make an extensive review of the MTX mechanism of action, pharmacokinetics, efficacy, safety and tolerability, especially focusing on the future perspective of this old drug and recent advances in the field of pharmacogenetics.

Power of crowdsourcing: novel methods of data collection in psoriasis and psoriatic arthritis

BACKGROUND

Crowdsourcing is a novel method of collecting research data from diverse patient populations. The quality of research data obtained through crowdsourcing is unknown.

OBJECTIVE

The primary aim of this pilot study was to examine how data collected from an online crowdsourcing World Wide Web site compare with those from published literature in psoriasis and psoriatic arthritis (PsA).

METHODS

Crowdsourced data were collected from a health crowdsourcing site from August 23, 2008, to June 27, 2011. The crowdsourced data were compared with findings from systematic reviews, meta-analyses, and clinical trials.

RESULTS

A total of 160 online patients with psoriasis or PsA were included in the analysis. Among them, 127 patients with psoriasis provided 313 complete responses on psoriasis symptoms and 276 complete responses to psoriasis treatments; 33 patients with PsA provided 91 complete responses on PsA symptoms and 79 responses to PsA treatments. We compared topical treatments, phototherapy, and systemic treatments for psoriasis and PsA from crowdsourced data with the published literature. For the treatment with the largest response rates, equivalency testing was performed comparing crowdsourced data and the published literature. Overall, crowdsourced data were not equivalent to those published in the medical literature.

LIMITATIONS

Crowdsourcing sites used different outcomes measures from those reported in clinical trials.

CONCLUSION

Differences existed in assessment of treatment effectiveness between crowdsourced data and those published in the literature. With improvements in the collection of crowdsourced data, crowdsourcing can be a valuable tool for collecting patient data in real-world settings for psoriasis and PsA.