Preliminary evidence for a role of mast cells in epidermal growth factor receptor inhibitor–induced pruritus

Comparison of gefitinib-induced skin adverse reactions (SAR) in C57BL/6 and FVB/N mice

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) such as gefitinib, erlotinib, and afatinib, are widely used in clinical practice and remarkably effective in treatment of advanced non-small cell lung cancer. However, there are some adverse effects while taking EGFR-TKIs, among which skin adverse reactions (SAR) are the most common events. At present, the poor outcome of SAR and insufficient research on SAR models need to be addressed. In this study we focused on the SAR models to lay a foundation for mechanism researches. Gefitinib, one of the EGFR-TKIs, was used as SAR inducing agents. We chose C57BL/6 and FVB/N mice as experimental model and they were divided into four groups. The weight and skin moisture of mice were detected every 7 days, itching behavior and abnormal eyelids were tested at 35th day after gavage, and survival rate was also recorded. The weight of unit area hair, length of whiskers and inflammatory cells were evaluated after mice sacrificed. C57BL/6 animals treated with gefitinib showed significant differences in survival rate, weight of unit area hair, skin moisture changes, skin dryness, itching behavior, whisker irregular growth, abnormal eyelids, and inflammatory cells; FVB/N animals treated with gefitinib only showed significant differences in survival rate, whisker irregular growth and abnormal eyelids, compared with the control group, respectively. In this study, we compared the similarities and differences of gefitinib-induced SAR between C57BL/6 and FVB/N mice, which illustrated different patients probably showing different symptoms clinically and provided experimental basis for researching mechanism of EGFR-TKIs induced SAR.

Neurokinin-1 antagonist orvepitant for EGFRI-induced pruritus in patients with cancer: a randomised, placebo-controlled phase II trial

OBJECTIVE

To evaluate the efficacy of orvepitant (10 or 30 mg given once daily, orally for 4 weeks), a neurokinin-1 receptor antagonist, compared with placebo in reducing the intensity of epidermal growth factor receptor inhibitor (EGFRI)-induced intense pruritus.

DESIGN

Randomised, double-blind, placebo-controlled clinical trial.

SETTING

15 hospitals in Italy and five hospitals in the UK.

PARTICIPANTS

44 patients aged ≥18 years receiving an EGFRI for a histologically confirmed malignant solid tumour and experiencing moderate or intense pruritus after EGFRI treatment.

INTERVENTION

30 or 10 mg orvepitant or placebo tablets once daily for 4 weeks (randomised 1:1:1).

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary endpoint was change from baseline in mean patient-recorded numerical rating scale (NRS) score (over the last three recordings) at week 4. Secondary outcome measures were NRS score, verbal rating scale score, Skindex-16 and Leeds Sleep Evaluation Questionnaire at each study visit (baseline, weeks 1, 4, 8); rescue medication use; EGFRI dose reduction; and study withdrawal because of intense uncontrolled pruritus.

RESULTS

The trial was terminated early because of recruitment challenges; only 44 of the planned 90 patients were randomised. All patients were analysed for efficacy and safety. Mean NRS score change from baseline to week 4 was -2.78 (SD: 2.64) points in the 30 mg group, -3.04 (SD: 3.06) points in the 10 mg group and -3.21 (SD: 1.77) points in the placebo group; the difference between orvepitant and placebo was not statistically significant. No safety signal was detected. Adverse events related to orvepitant (asthenia, dizziness, dry mouth, hyperhidrosis) were all of mild or moderate severity.

CONCLUSIONS

Orvepitant was safe and well tolerated. No difference in NRS score between the orvepitant and placebo groups was observed at the week 4 primary endpoint. A number of explanations for this outcome are possible.

TRIAL REGISTRATION NUMBER

EudraCT2013-002763-25.

Aprepitant for gefitinib-induced refractory pruritus in Chinese malignancy population

Targeted therapy is an important anti-cancer therapy in non-small cell lung cancer (NSCLC). Pruritus are the common side-effect with gefitinib, an anti-EGFR antibody and tyrosine-kinase inhibitor. We reported case reports to confirm the effects of aprepitant, a neurokinin receptor to management of refractory rash and pruritus in Chinese malignancy population. patients showed a rapid recovery from refractory pruritus, no adverse events occurred. Weekly follow-up visits showed the pruritus were stable and no further episodes was recorded.

Tissue-specific contributions of Tmem79 to atopic dermatitis and mast cell-mediated histaminergic itch

Atopic dermatitis (AD) is the most common skin disease in children. It is characterized by relapsing inflammation, skin-barrier defects, and intractable itch. However, the pathophysiology of itch in AD remains enigmatic. Here, we examine the contribution of Tmem79, an orphan transmembrane protein linked to AD in both mice and humans. We show that Tmem79 is expressed by both keratinocytes and sensory neurons, but that loss of keratinocytic Tmem79 is sufficient to elicit robust scratching. Tmem79-/- mice demonstrate an accumulation of dermal mast cells, which are diminished following chronic treatment with cyclooxygenase inhibitors and an EP3 receptor antagonist. In Tmem79-/- mice, mast cell degranulation produces histaminergic itch in a histamine receptor 1/histamine receptor 4 (H4R/H1R)-dependent manner that may involve activation of TRPV1- afferents. TMEM79 has limited sequence homology to a family of microsomal glutathione transferases and confers protection from cellular accumulation of damaging reactive species, and may thus play a role in regulating oxidative stress. In any case, mechanistic insights from this model suggest that therapeutics targeting PGE2 and/or H1R/H4R histaminergic signaling pathways may represent useful avenues to treat Tmem79-associated AD itch. Our findings suggest that individuals with mutations in Tmem79 develop AD due to the loss of protection from oxidative stress.

Efficacy of hydrophilic or lipophilic emulsions containing Echinacea purpurea extract in treatment of different types of pruritus

Background

Pruritus reduces quality of life and may occur at different sites of the body. To alleviate pruritus, lipid replenishing and rehydration of the skin is often unsatisfactory. Thus, products with additional antipruritic effects are needed.

Objectives

Antipruritic effects and cosmetic properties of two different emulsions, water-in-oil (w/o) or oil-in-water (o/w), and a shampoo containing a lipophilic Echinacea purpurea root extract (Ec.-extract) were assessed in adults suffering from pruritus.

Methods

Adults (n = 55) with pruritus of the body applied a w/o emulsion for 2 weeks. In a separate study, adults (n = 33) with a pruritic scalp applied an o/w-emulsion for 4 weeks. In a third study, shampoo (n = 34) was applied for 4 weeks. Objective (erythema, dryness, and papules) and subjective (intensity, duration, and burden of pruritus) parameters were assessed.

Results

Treatment with the w/o emulsion significantly reduced erythema and dryness (P < 0.0001) as well as pruritus (in 93% of participants) on the body. Treatment with the o/w-emulsion on the scalp significantly (P < 0.0001) reduced objective (erythema in 61% and dryness in 85% of participants) and subjective (85% of participants had reduced pruritus) parameters. Similar results in reduction of dryness (76% of participants) and pruritus (70 % of participants) were seen after 4 weeks of shampoo use.

Conclusion

Independent from the type of emulsion (w/o or o/w), cosmetic products containing a proprietary Ec.-extract significantly reduced objective and subjective parameters in adults suffering from acute or chronic pruritus exhibiting excellent tolerability.

Mechanisms of skin aging induced by EGFR inhibitors

BACKGROUND

The mechanisms of skin aging have not been completely elucidated. Anecdotal data suggests that EGFR inhibition accelerates aging-like skin changes.

OBJECTIVE

The objective of the study was to evaluate the clinical characteristics and investigate the cellular and molecular mechanisms underlying skin changes associated with the use of EFGRIs.

PATIENTS AND METHODS

Patients during prolonged treatment with EGFRIs (>3 months) were analyzed for aging-like skin changes. Baseline EGFR expression was compared in young (<25 years old) vs. old (> 65 years old) skin. In addition, the regulation of extracellular matrix, senescence-associated genes, and cell cycle status was measured in primary human keratinocytes treated with erlotinib in vitro.

RESULTS

There were progressive signs of skin aging, including xerosis cutis, atrophy, rhytide formation, and/or actinic purpura in 12 patients. Keratinocytes treated with erlotinib in vitro showed a significant down-modulation of hyaluronan synthases (HAS2 and HAS3), whereas senescence-associated genes (p21, p53, IL-6, maspin) were upregulated, along with a G1 cell cycle arrest and stronger SA β-Gal activity. There was significantly decreased baseline expression in EGFR density in aged skin, when compared to young controls.

CONCLUSIONS

EGFR inhibition results in molecular alterations in keratinocytes that may contribute to the observed skin aging of patients treated with respective targeted agents.

Dermatologic adverse events in pediatric patients receiving targeted anticancer therapies: a pooled analysis

BACKGROUND

The dermatologic adverse events (AEs) of various molecularly targeted therapies are well-described in adult cancer patients. Little has been reported on the incidence and clinical presentation of such AEs in pediatric patients with cancer. To address this gap, we analyzed the dermatologic AEs reported across clinical trials of targeted anticancer therapies in pediatric patients.

PROCEDURES

We conducted an electronic literature search (PubMed, American Society of Clinical Oncology annual meetings' abstracts, ClinicalTrials.gov, NCI's Pediatric Oncology Branch webpage) to identify clinical trials involving targeted anticancer therapies that reported dermatologic AEs in their safety data. Studies were limited to the pediatric population, monotherapy trials (oncology), and English language publications.

RESULTS

Pooled data from 19 clinical studies investigating 11 targeted anticancer agents (alemtuzumab, rituximab, imatinib, dasatinib, erlotinib, vandetanib, sorafenib, cabozantinib, pazopanib, everolimus, and temsirolimus) were analyzed. The most frequently encountered dermatologic AEs were rash (127/660; 19%), xerosis (18/100; 18%), mucositis (68/402; 17%), and pruritus (12/169; 7%). Other AEs included pigmentary abnormalities of the skin/hair (13%), hair disorders (trichomegaly, hypertrichosis, alopecia, and madarosis; 14%), urticaria (7%), palmoplantar erythrodysesthesia (7%), erythema, acne, purpura, skin fissures, other 'unknown skin changes', exanthem, infection, flushing, telangiectasia, and photosensitivity.

CONCLUSION

This study describes the dermatologic manifestations of targeted anticancer therapy-related AEs in the pediatric population. Since these AEs are often associated with significant morbidity, it is imperative that pediatric oncologists be familiar with their recognition and management, to avoid unnecessary dose modifications and/or termination, and to prevent impairments in patients' quality of life.

IL-33/IL-31 axis: a new pathological mechanisms for EGFR tyrosine kinase inhibitors-associated skin toxicity

The dermatologic side effects are the most common adverse effects associated with Epidermal Growth Factor Receptor tyrosine kinase inhibitors. Although the mechanisms underlying the development of the skin toxicity remain unclear, immunological mechanisms are considered to be involved. A possible correlation between plasma levels of certain cytokines and development of skin toxicity has been reported. The aim of this work was to investigate the possible contribution of IL-31 and IL-33, cytokines involved in disorders associated with itching, in the pathogenesis of pruritus in patients undergoing EGFR-TK inhibitors. We report a significant increase of IL-31 and IL-33 serum levels in a patient with a bronchioalveolar carcinoma, who had showed previous skin rash, xerosis, and pruritus during treatment with different EGFR-TK inhibitors. She developed intense iching during gefitinib therapy. Therefore, we had collected patient blood sample to evaluate IL-31 and IL-33 serum levels compared to controls, reporting a significant increase in serum of patient. In the light of these findings, EGFR-TK inhibitors-related symptoms of dermatologic toxicities might be related to the release of IL-31 and IL-33. In particular, it is supposable that EGFR-TK inhibitors could cause keratinocytes injury, the release of IL-33 and the consequent interaction with its receptor on mast cells, that induces the secretion of several factors capable to cause skin manifestations, included IL-31, a known pruritus-inducing cytokine. This report, to the best of our knowledge, is the first work describing a possible involvement of IL-31/IL-33 axis in the pathogenesis of skin side effects related to EGFR-TK inhibitors treatment.

Genetic ablation of epidermal EGFR reveals the dynamic origin of adverse effects of anti-EGFR therapy

Cancer patients treated with anti-EGFR (epidermal growth factor receptor) drugs often develop a dose-limiting pruritic rash of unknown etiology. The aims of our study were to define causal associations from a clinical study of cutaneous and systemic changes in patients treated with gefitinib and use these to develop and characterize a mouse model that recapitulates the human skin rash syndrome caused by anti-EGFR therapy. We examined the patients' plasma before and after treatment with gefitinib and documented changes in chemokines and leukocyte counts associated with the extent of rash or the presence of pruritus. We established a parallel mouse model by ablating EGFR in the epidermis. These mice developed skin lesions similar to the human rash. Before lesion development, we detected increased mRNA expression of chemokines in the skin associated with early infiltration of macrophages and mast cells and later infiltration of eosinophils, T cells, and neutrophils. As the skin phenotype evolved, changes in blood counts and circulating chemokines reproduced those seen in the gefitinib-treated patients. Crossing the mutant mice with mice deficient for tumor necrosis factor-α (TNF-α) receptors, MyD88, NOS2, CCR2, T cells, or B cells failed to reverse the skin phenotype. However, local depletion of macrophages provided partial resolution, suggesting that this model can identify targets that may be effective in preventing the troublesome and dose-limiting skin response to anti-EGFR drugs. These results highlight the importance of EGFR signaling in maintaining skin immune homeostasis and identify a macrophage contribution to a serious adverse consequence of cancer chemotherapy.

Dermatological adverse events from BRAF inhibitors: a growing problem

The development of targeted therapies has ushered in a new era in the management of melanoma. Inhibitors of the RAS-RAF-MEK-ERK pathway have taken the center stage with development at a rapid pace. Vemurafenib was recently approved by regulatory agencies, and other agents (e.g. dabrafenib) are in various stages of clinical testing. These agents are producing remarkable results for patients, but are also presenting new challenges. Clinical toxicities and drug resistance are topmost issues. Some of the most common and vivid representations of adverse events to these agents are the dermatologic manifestations. Published trials and initial observations reflect a toxicity profile (e.g. squamous cell carcinomas/keratoacanthomas, maculopapular rashes, hyperkeratosis) that is distinct from cutaneous toxicities from EGFR and mTOR inhibitors (acneiform rash, paronychia, xerosis). Their management extends beyond conservative treatment and includes specific physical and surgical treatment modalities, skill sets unique to dermatologists. All these pose significant challenges to clinicians, and sound knowledge of such toxicities and their management will likely result in improved patient outcomes and quality of life. In this manuscript, we provide an overview of the emerging scientific literature on dermatological adverse events arising out of BRAF inhibition.

Pruritus in patients treated with targeted cancer therapies: systematic review and meta-analysis

BACKGROUND

Pruritus has been anecdotally described in association with targeted cancer therapies. The risk of pruritus has not been systematically ascertained.

OBJECTIVE

A systematic review and meta-analysis of the literature was conducted for axitinib, cetuximab, dasatinib, erlotinib, everolimus, gefitinib, imatinib, ipilimumab, lapatinib, nilotinib, panitumumab, pazopanib, rituximab, sorafenib, temsirolimus, tositumomab, vandetanib, and vemurafenib.

METHODS

Databases from PubMed, Web of Science (January 1998 through July 2012), and American Society of Clinical Oncology abstracts (2004 through 2012) were searched. Incidence and relative risk of pruritus were calculated using random- or fixed-effects model.

RESULTS

The incidences of all-grade and high-grade pruritus were 17.4% (95% confidence interval 16.0%-19.0%) and 1.4% (95% confidence interval 1.2%-1.6%), respectively. There was an increased risk of all-grade pruritus (relative risk 2.90 [95% confidence interval 1.76-4.77, P < .001]) and variation among different drugs (P < .001).

LIMITATIONS

The reporting of pruritus may vary, resulting from concomitant medications, comorbidities, and underlying malignancies. We found a higher incidence of pruritus in patients with solid tumors, concordant with those targeted therapies with the highest pruritus incidences.

CONCLUSION

There is a significant risk of developing pruritus in patients receiving targeted therapies. To prevent suboptimal dosing and decreased quality of life, patients should be counseled and treated against this untoward symptom.

Aprepitant for management of severe pruritus related to biological cancer treatments: a pilot study

BACKGROUND

Itch is a common side-effect of treatment with anti-EGFR antibodies and tyrosine-kinase inhibitors. We designed a pilot single-centre study to assess the effects of aprepitant-a neurokinin receptor inhibitor-for management of severe pruritus induced by biological drugs.

METHODS

In this single-group, prospective study, we consecutively enrolled 45 outpatients with metastatic solid tumours treated with biological drugs at the Campus Bio-Medico Hospital of Rome, Rome, Italy, between September, 2010, and November, 2011. We classified patients into two groups: a refactory group, for patients with pruritis refractory to standard treatment, or a naive group, for patients who had not been previously treated for pruritis. Aprepitant (125 mg on day 1; 80 mg on day 3; 80 mg on day 5) was given to patients in the refractory group after at least 1 week of standard systemic treatment. In the naive group, aprepitant was given in the same schedule as the refractory group, after first onset of severe pruritus. Intensity of itch was evaluated by Visual Analogue Scale (VAS) score. The primary endpoint was change in median VAS score. This trial is registered with ClinicalTrials.gov, number NCT01683552.

FINDINGS

Median VAS in the refractory group was 8·00 (95% CI 7·93-8·57) at baseline and 1·00 (0·00-2·00) after 1 week of treatment with aprepitant (p<0·0001). In the naive group, VAS score was 8·00 (7·43-8·37) at baseline and 0·00 (0·06-1·08) after 1 week of treatment (p<0·0001). 41 (91%) patients responded to aprepitant (ie, had a >50% reduction in intensity of pruritis) and pruritus recurred in only six (13%) patients. No adverse events related to aprepitant occurred.

INTERPRETATION

Aprepitant decreases severe pruritus induced by biological treatments; it is an old drug, widely available, and therefore easy to add to the armamentarium of supportive treatment. Although to our knowledge no other studies of the anti-itch activity of aprepitant are planned, the results of our trial warrant confirmation in phase 2 and 3 trials.

FUNDING

None.

Escalating therapy of cutaneous side effects of EGFR inhibitors: experience of German reference centers

Recommendations for the management of cutaneous adverse effects of inhibitors of the epidermal growth factor receptor (EGFR) are urgently needed. In this context an expert panel of German dermatologists recently proposed a 3-step management concept based on personal experience and a current literature consensus. While steps 1 and 2 addressed general and preventive measures, as well as the therapy that can be performed by the primary treating physician, here we address the management of challenging cases (step 3) that do not respond well to basic measures and should be referred to an experienced dermatologist.

Management of EGFR-inhibitor associated rash: a retrospective study in 49 patients

BACKGROUND

In recent years inhibitors directed against the epidermal growth factor receptor (EGFR) have evolved as effective targeting cancer drugs. Characteristic papulopustular exanthemas, often described as acneiform rashes, are the most frequent adverse effect associated with this class of novel cancer drugs and develop in > 90% of patients. Notably, the rash may significantly compromise the patients' quality of life, thereby potentially leading to incompliance as well as dose reduction or even termination of the anti-EGFR therapy. Yet, an effective dermatologic management of cutaneous adverse effects can be achieved. Whereas various case reports, case series or expert opinions on the management of EGFR-inhibitor (EGFRI) induced rashes have been published, data on systematic management studies are sparse.

METHODS

Here, we present a retrospective, uncontrolled, comparative study in 49 patients on three established regimens for the management of EGFRI-associated rashes.

RESULTS

Strikingly, patients' rash severity improved significantly over three weeks of treatment with topical mometason furoate cream, topical prednicarbate cream plus nadifloxacin cream, as well as topical prednicarbate cream plus nadifloxacin cream plus systemic isotretinoin.

CONCLUSIONS

In summary our results demonstrate that EGFRI-associated rashes can be effectively managed by specific dermatologic interventions. Whereas mild to moderate rashes should be treated with basic measures in combination with topical glucocorticosteroids or combined regiments using glucocorticosteroids and antiseptics/antibiotics, more severe or therapy-resistant rashes are likely to respond with the addition of systemic retinoids.

Rosacea: The cytokine and chemokine network

Rosacea is one of the most common dermatoses of adults. Recent studies have improved our understanding of the pathophysiology of rosacea. Current concepts suggest that known clinical trigger factors of rosacea such as UV radiation, heat, cold, stress, spicy food, and microbes modulate Toll-like receptor signaling, induce reactive oxygen species, as well as enhance antimicrobial peptide and neuropeptide production. Downstream of these events cytokines and chemokines orchestrate an inflammatory response that leads to the recruitment and activation of distinct leukocyte subsets and induces the characteristic histopathological features of rosacea. Here we summarize the current knowledge of the cytokine and chemokine network in rosacea and propose pathways that may be of therapeutic interest.

Phenylbutyrate suppresses distinct skin reactions that are enhanced by blockade of epidermal growth factor receptor signaling

BACKGROUND

Epidermal growth factor receptor inhibitors (EGFRIs) cause skin inflammation, and understanding the factors that mediate this reaction is fundamental for designing therapies for EGFRI-related cutaneous side effects.

OBJECTIVE

We characterized EGFRI-enhanced skin reactions and evaluated the therapeutic efficacy of phenylbutyrate, a histone deacetylase inhibitor.

METHODS

PD168393, an EGFRI, was applied topically to the ear skin of mice with or without mast cell deficiency. The skin was then irritated once or pre-sensitized and repeatedly challenged with 2,4-dinitrofluorobenzene (DNFB). The reaction pattern, the type and number of infiltrating cells, changes in protein, cytokine (TNF-α) and chemokine (CCL2) expression, and the immune response were analyzed. Phenylbutyrate, formulated as a gel for topical treatment or dissolved in water for intraperitoneal administration, was tested as a treatment.

RESULTS

EGFRI rapidly upregulated the mast cell chemotactic factor, stem cell factor (SCF) and augmented DNFB-induced immediate contact dermatitis within hours of treatment in the presence of mast cells. Topical phenylbutyrate treatment suppressed EGFRI-induced SCF expression in the epithelium, inhibited DNFB-induced mast cell recruitment in the dermis, and ameliorated the EGFRI-enhanced acute skin reaction. EGFRI also enhanced the delayed-type DNFB-induced hypersensitive reaction that was mast-cell independent but was associated with T lymphocytes. Systemic phenylbutyrate administration suppressed EGFRI-enhanced delayed-type skin hypersensitivity by increasing the number and function of Foxp3(+) T regulatory suppressor cells, which inhibited T helper cell proliferation.

CONCLUSIONS

Our data suggest that phenylbutyrate has dual beneficial therapeutic effects on EGFRI-enhanced acute (local inflammatory) and late (systemic immune) skin reactions.

Density of Demodex folliculorum in patients receiving epidermal growth factor receptor inhibitors

BACKGROUND

Rosacea-like papulopustular eruptions (rash) are considered the most frequent toxicities associated with the use of inhibitors of the epidermal growth factor receptor (EGFR). Recently, evidence has been accumulating of infectious complications in patients suffering from these adverse effects.

OBJECTIVE

We sought to analyze the density of Demodex folliculorum (DF) in cutaneous lesions of patients presenting with EGFR-inhibitor (EGFRI)-induced rashes.

METHODS

This is a retrospective study of 19 adult patients presenting with EGFRI rashes. Patients were reviewed for the density of DF (Demodex density, Dd; mites per square centimeter) by standardized skin surface biopsy.

RESULTS

In our patient collective the mean Dd of 4.7/cm² significantly exceeded the mean Dd reported for the healthy adult population (Dd = 0.7/cm²).

LIMITATIONS

The retrospective nature of the study.

CONCLUSIONS

EGFRI patients have an increased susceptibility to DF colonization or infection, respectively. Our results support the recent concept that EGFRI may induce an impairment of antimicrobial defense mechanisms.