Neutralization of IL-8 prevents the induction of dermatologic adverse events associated with the inhibition of epidermal growth factor receptor

Risk Factor Analysis for Anti-epidermal Growth Factor Receptor Monoclonal Antibody-induced Problematic Skin Toxicities in Patients With Liver Metastatic Colorectal Cancer

BACKGROUND/AIM

We previously reported that patients with metastatic colorectal cancer (mCRC) and baseline liver metastasis are at a higher risk of developing grade ≥2 overall skin toxicities when treated with anti-epidermal growth factor receptor (EGFR) monoclonal antibody. This study aimed to identify additional factors associated with skin toxicities induced by anti-EGFR treatment in patients with liver metastatic CRC.

PATIENTS AND METHODS

Patients with liver metastatic CRC who initially received anti-EGFR monoclonal antibody-containing treatment (n=77) were retrospectively assessed. The primary endpoint was to identify the factor(s) responsible for the development of grade ≥2 overall skin toxicities. Additionally, factors for grade ≥2 rash and paronychia were evaluated.

RESULTS

The incidence of grade ≥2 overall skin symptoms, rash, and paronychia was 62.3%, 31.2%, and 28.6%, respectively. Multivariate Cox proportional hazard regression analyses revealed that age <65 years and anemia were independent baseline risk factors for grade ≥2 overall skin toxicities (adjusted hazard ratio 2.09, 95% confidence interval=1.10-3.97, p=0.02 for age; 2.36, 1.20-4.61, p=0.01 for anemia). In contrast, combination prophylaxis using systemic minocycline and corticosteroid ointment was a preventive factor (0.47, 0.25-0.88, p=0.02). Males and age <65 years were baseline risk factors for grade ≥2 rash, and combination prophylaxis was identified as a preventive factor. No factors were identified for paronychia.

CONCLUSION

Age <65 years and anemia were identified as independent baseline risk factors. Additionally, combination prophylaxis was found to be a preventive factor against anti-EGFR monoclonal antibody-induced grade ≥2 overall skin toxicities in patients with liver metastatic CRC.

Subcutaneous Administration of Monoclonal Antibodies: Pharmacology, Delivery, Immunogenicity, and Learnings From Applications to Clinical Development

Subcutaneous (s.c.) administration of monoclonal antibodies (mAbs) can reduce treatment burden for patients and healthcare systems compared with intravenous (i.v.) infusion through shorter administration times, made possible by convenient, patient-centric devices. A deeper understanding of clinical pharmacology principles related to efficacy and safety of s.c.-administered mAbs over the past decade has streamlined s.c. product development. This review presents learnings from key constituents of the s.c. mAb development pathway, including pharmacology, administration variables, immunogenicity, and delivery devices. Restricted mAb transportation through the hypodermis explains their incomplete absorption at a relatively slow rate (pharmacokinetic (PK)) and may impact mAb-cellular interactions and/or onset and magnitude of physiological responses (pharmacodynamic). Injection volumes, formulation, rate and site of injection, and needle attributes may affect PKs and the occurrence/severity of adverse events like injection-site reactions or pain, with important consequences for treatment adherence. A review of immunogenicity data for numerous compounds reveals that incidence of anti-drug antibodies (ADAs) is generally comparable across i.v. and s.c. routes, and complementary factors including response magnitude (ADA titer), persistence over time, and neutralizing antibody presence are needed to assess clinical impact. Finally, four case studies showcase how s.c. biologics have been clinically developed: (i) by implementation of i.v./s.c. bridging strategies to streamline PD-1/PD-L1 inhibitor development, (ii) through co-development with i.v. presentations for anti-severe acute respiratory syndrome-coronavirus 2 antibodies to support rapid deployment of both formulations, (iii) as the lead route for bispecific T cell engagers (BTCEs) to mitigate BTCE-mediated cytokine release syndrome, and (iv) for pediatric patients in the case of dupilumab.

Risk factor analysis for anti-epidermal growth factor receptor monoclonal antibody-induced skin toxicities in real-world metastatic colorectal cancer treatment

PURPOSE

Anti-epidermal growth factor receptor (anti-EGFR) monoclonal antibodies are effective in treating RAS wild-type metastatic colorectal cancer (mCRC). However, their administration induces skin toxicity, markedly reducing patients' quality of life. This study is aimed at identifying the risk factors associated with anti-EGFR monoclonal antibody-induced skin toxicities.

METHODS

Patients with mCRC (n = 116) who received anti-EGFR monoclonal antibody treatment were retrospectively evaluated. Primary endpoint was evaluation of the risk factors for grade ≥ 2 overall skin toxicities during all the treatment periods. Furthermore, factors associated with each grade ≥ 2 skin symptoms were assessed.

RESULTS

Incidence of total grade ≥ 2 skin toxicity symptoms was 61.2%, and those of grade ≥ 2 rash, dry skin, fissures, and paronychia were 34.5%, 25.9%, 20.7%, and 25.0%, respectively. Multivariate logistic regression analyses revealed that liver metastasis was an independent risk factor for overall grade ≥ 2 skin toxicities (adjusted odds ratio [OR], 2.88; 95% confidence interval [CI], 1.22-6.78; P = 0.02) and prophylactic administration of antibiotics as a preventive factor (OR 0.10; 95%CI 0.01-0.91; P = 0.04). For grade ≥ 2 rash, prophylactic use of systemic antibiotics and topical steroid ointment was a preventive factor (OR 0.37; 95%CI 0.16-0.89; P = 0.03). Moreover, liver metastasis (OR 8.37; 95%CI 1.98-35.47; P = 0.004) and prophylactic administration of antibiotics (OR 0.15; 95%CI 0.03-0.76; P = 0.02) were significantly associated with grade ≥ 2 paronychia.

CONCLUSION

Liver metastasis was suggested to be a risk factor for the incidence of overall grade ≥ 2 skin toxicities; moreover, preemptive systemic antibiotic administration drastically decreased this risk during all periods of anti-EGFR treatment for mCRC.

Xijiao Dihuang decoction relieves the erlotinib-induced dermatitis

BACKGROUND

Erlotinib treatment can lead to skin diseases that drastically affected the quality of life of patients. Quercetin (Que), the active component in Xijiao Dihuang Decoction (XDD), was identified to improve inflammatory skin diseases. However, the mechanism of XDD treating erlotinib-induced cutaneous toxicity was not clear at the molecular level.

METHODS

Keratinocytes were treated with erlotinib, and the expression of inflammatory cytokines and chemokines was revealed by ELISA and qRT-PCR. The macrophage polarization was determined by flow cytometry. The key component of XDD, Que, and the target genes of dermatitis were selected via network pharmacology analysis. The binding effects of Que and target genes were verified using molecular docking and cellular thermal shift assay (CETSA)-western blot assay. Animal experiments were performed in vivo to verify the therapeutic effect of XDD on erlotinib-induced skin toxicity.

RESULTS

Erlotinib induced M1 polarization of macrophages after stimulating epidermal keratinocytes. While this effect was associated with increased production of inflammatory cytokines and chemokines, such production was prominently decreased by XDD treatment. By combining network pharmacological analysis, molecular docking, and CETSA, it was confirmed that Que had a binding relationship with IL-2 and CXCL8. In vivo results implied that erlotinib abated tumor growth and stimulated dermatitis in HR-1 nude mice, while Que alleviated erlotinib-induced skin damage without affecting this tumor repression effect.

CONCLUSION

The results indicated that XDD could relieve the dermatitis induced by erlotinib and provide a favorable theoretical basis for the clinical relief by using this method.

Identification of immune-related mechanisms of cetuximab induced skin toxicity in colorectal cancer patients

Skin rash is a well-known predictive marker of the response to cetuximab (Cmab) in metastatic colorectal cancer (mCRC). However, the mechanism of skin rash development is not well understood. Following exposure to EGFR-targeted therapies, changes in IL-8 levels have been reported. The aim of this study was to evaluate the association between skin rash and inflammatory cytokine levels, including IL-8. Between 2014 and 2017, we prospectively enrolled 38 mCRC patients who underwent chemotherapy with either Cmab or bevacizumab (Bmab) at two hospitals. We performed multiplex cytokine ELISA with 20 inflammatory cytokines including E-selectin, GM-CSF, IFN-alpha, IFN-γ, IL-1 alpha, IL-1 beta, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, IL-17A, IP-10, MCP-1, MIP-1 alpha, MIP-1 beta, P-selectin, sICAM-1, and TNF-alpha at baseline before cycle 1, 24 h after cycle 1, before cycle 2 (= 14 d), and before cycle 3 (= 28 d). Cytokine levels were compared using ANOVA after log-transformation. IL-8 genotypes in 30 patients treated with Cmab were determined using the polymerase chain reaction restriction fragment length polymorphism technique. Depending on the RAS mutational status, 30 and eight patients were treated with Cmab and Bmab-based chemotherapy, respectively. Skin rash developed in 23 (76.6%) of the 30 patients treated with Cmab plus FOLFIRI, after cycle 1. Only the mean log-transformed serum IL-8 level in patients with skin toxicity was statistically lower (2.83 ± 0.15) than in patients who did not experience skin toxicity (3.65 ± 0.27) and received Bmab (3.10 ± 0.26) (ANOVA test, p value = 0.0341). In addition, IL-8 polymorphism did not affect IL-8 levels, skin toxicity, or tumor response in Cmab treated patients. This study suggests that the inflammatory cytokine levels might be affected by Cmab exposure and are associated with the development of skin rash in mCRC patients. Further studies are warranted to evaluate this interaction in Cmab treated patients.

Composition and Bioactivity of a Modified Huang-Lian-Jie-Du Decoction

Background. Epidermal growth factor receptor inhibitors (EGFRIs) and tyrosine kinase inhibitors (TKIs) are key drugs in targeted cancer therapy. However, they may cause skin toxicity. We previously prepared a modified Huang-Lian-Jie-Du (mHLJD) decoction cream using 10 herbs, which effectively alleviated EGFRI/TKI-induced skin toxicity. In the present study, we identified the reference markers of the mHLJD decoction and investigated the anti-inflammatory and antibacterial effects of the mHLJD decoction extract. Methods. We performed high-performance liquid chromatography (HPLC) to determine the composition of the mHLJD decoction. Human epidermoid A431 cells were treated with tumor necrosis factor (TNF)-α to induce inflammation; then, the effects of the mHLJD decoction extract on the cytokine expression were determined using a cytokine array and by performing real-time quantitative polymerase chain reaction (qPCR). The antibacterial effects of the extract were examined using disk diffusion and microdilution assays. Results. HPLC results revealed that the mHLJD decoction primarily consisted of geniposide, berberine chloride, baicalin, coptisine, and palmatine. TNF-α treatment increased the expression of certain cytokines, including IL-1β, IL-8, M-CSF, and TGF-β2; however, pretreatment with the mHLJD decoction extract reduced their expression. The qPCR results demonstrated a decreased mRNA expression of IL-8, M-CSF, and TGF-β2. The antibacterial assay revealed that the extract exerted inhibitory effects on Staphylococcus aureus, forming an inhibition zone at the minimum inhibitory concentrations of 3.125 and 6.25 mg/mL; however, the extract exerted no effects on Escherichia coli and Pseudomonas aeruginosa. Conclusions. We developed an HPLC method to quantify the reference markers of the mHLJD decoction. The bioactivity analysis provided the potential mechanisms underlying the effects of the mHLJD decoction on EGFRI/TKI-induced skin toxicity.

Prophylactic Topical Treatment for EGFR Inhibitor-Induced Papulopustular Rash: A Randomized Clinical Trial

BACKGROUND

The incidence of epidermal growth factor receptor inhibitor (EGFRI)-induced papulopustular rash is 60-85%.

OBJECTIVE

To investigate prophylactic topical treatment for EGFRI-induced rash.

METHODS

A single-center, randomized, double-blind, placebo-controlled trial. Adult cancer patients initiating treatment with EGFRIs were randomized to receive facial topical treatment with chloramphenicol 3% + prednisolone 0.5% (CHL-PRED) ointment, chloramphenicol 3% (CHL) ointment, or aqua cream (AQUA). The primary end points were the incidence of ≥grade 3 rash using the Common Terminology Criteria for Adverse Events (CTCAE), on days 14 and 30. A subanalysis was conducted for incidence of a protocol-specified significant rash, defined as ≥10 facial papulopustular lesions.

RESULTS

The per-protocol analysis on day 14 included 69 patients, who received CHL-PRED (21), CHL (23), or AQUA (25). The incidence of CTCAE ≥grade 3 rash was not statistically significant between arms; however, the incidence of the protocol-specified significant rash was: CHL-PRED 14%, CHL 39%, and AQUA 48% (p = 0.03, CHL-PRED vs. AQUA). At 30 days, the CTCAE ≥grade 3 incidence was similar, but the incidences of protocol-specified significant rash were 6%, 16%, and 43% (p = 0.03, CHL-PRED vs. AQUA). No significant differences were found between CHL and CHL-PRED and between CHL and AQUA.

CONCLUSIONS

Prophylactic topical CHL-PRED was efficacious when compared to AQUA, in the treatment of EGFRI-induced facial papulopustular rash.

Discovery and characterization of a neutralizing pan-ELR+CXC chemokine monoclonal antibody

CXCR1 and CXCR2 signaling play a critical role in neutrophil migration, angiogenesis, and tumorigenesis and are therefore an attractive signaling axis to target in a variety of indications. In human, a total of seven chemokines signal through these receptors and comprise the ELR⁺CXC chemokine family, so named because of the conserved ELRCXC N-terminal motif. To fully antagonize CXCR1 and CXCR2 signaling, an effective therapeutic should block either both receptors or all seven ligands, yet neither approach has been fully realized clinically. In this work, we describe the generation and characterization of LY3041658, a humanized monoclonal antibody that binds and neutralizes all seven human and cynomolgus monkey ELR⁺CXC chemokines and three of five mouse and rat ELR⁺CXC chemokines with high affinity. LY3041658 is able to block ELR⁺CXC chemokine-induced Ca²⁺ mobilization, CXCR2 internalization, and chemotaxis in vitro as well as neutrophil mobilization in vivo without affecting other neutrophil functions. In addition to the in vitro and in vivo activity, we characterized the epitope and structural basis for binding in detail through alanine scanning, crystallography, and mutagenesis. Together, these data provide a robust preclinical characterization of LY3041658 for which the efficacy and safety is being evaluated in human clinical trials for neutrophilic skin diseases.

IL-36γ drives skin toxicity induced by EGFR/MEK inhibition and commensal Cutibacterium acnes

Epidermal growth factor receptor (EGFR) and MEK inhibitors (EGFRi/MEKi) are beneficial for the treatment of solid cancers but are frequently associated with severe therapy-limiting acneiform skin toxicities. The underlying molecular mechanisms are poorly understood. Using gene expression profiling we identified IL-36γ and IL-8 as candidate drivers of EGFRi/MEKi skin toxicity. We provide molecular and translational evidence that EGFRi/MEKi in concert with the skin commensal bacterium Cutibacterium acnes act synergistically to induce IL-36γ in keratinocytes and subsequently IL-8, leading to cutaneous neutrophilia. IL-36γ expression was the combined result of C. acnes–induced NF-κB activation and EGFRi/MEKi–mediated expression of the transcription factor Krüppel-like factor 4 (KLF4), due to the presence of both NF-κB and KLF4 binding sites in the human IL-36γ gene promoter. EGFRi/MEKi increased KLF4 expression by blockade of the EGFR/MEK/ERK pathway. These results provide an insight into understanding the pathological mechanism of the acneiform skin toxicities induced by EGFRi/MEKi and identify IL-36γ and the transcription factor KLF4 as potential therapeutic targets.

Dapsone as treatment adjunct in ARDS

Multiple pharmacological interventions tested over the last decades have failed to reduce ARDS mortality. This short note recounts past data indicating that (i) neutrophils home along an IL-8 gradient, (ii) in ARDS, massive neutrophil accumulation and degranulation in and along bronchoalveolar spaces contributes to damage and hypoxia, (iii) large increases in IL-8 are one of the chemotaxic signals drawing neutrophils to the ARDS lung, and (iv) old data from dermatology and glioblastoma research showed that the old drug against Hansen’s disease, dapsone, inhibits neutrophils’ chemotaxis to IL-8. Therefore dapsone might lower neutrophils’ contributions to ARDS lung pathology. Dapsone can create methemoglobinemia that although rarely problematic it would be particularly undesirable in ARDS. The common antacid drug cimetidine lowers risk of dapsone related methemoglobinemia and should be given concomitantly.

Dioscin alleviates lipopolysaccharide-induced acute lung injury through suppression of TLR4 signaling pathways

Aim: Acute lung injury (ALI) is a life-threatening inflammatory syndrome that lacks an effective therapy. Dioscin, a natural steroid saponin isolated from a variety of herbs, could serve as an anti-inflammatory agent, as suggested in previous reports. The purpose of this study was to explore the effects of dioscin on lipopolysaccharide (LPS)-induced ALI and validate the potential mechanisms.Materials and Methods: An ALI model was induced by intratracheal administration of LPS. Dioscin (20, 40, and 80 mg/kg) was administered intragastrically once daily for seven consecutive days prior to LPS challenge.Results: Our data revealed that dioscin significantly suppressed LPS-induced lung pathological changes, pulmonary capillary permeability, pulmonary edema, inflammatory cell infiltration, myeloperoxidase (MPO) activity, and cytokine production, including tumor necrosis factor (TNF)-α, interleukin (IL)-6, and keratinocyte chemoattractant (KC). Moreover, dioscin inhibited LPS-induced nuclear factor-kappaB (NF-κB) activation as well as Toll-like receptor 4 (TLR4) expression.Conclusions: In brief, the results indicated that dioscin alleviates LPS-induced ALI through suppression of TLR4 signaling pathways.

Phase I trial of HuMax-IL8 (BMS-986253), an anti-IL-8 monoclonal antibody, in patients with metastatic or unresectable solid tumors

BACKGROUND

HuMax-IL8 (now known as BMS-986253) is a novel, fully human monoclonal antibody that inhibits interleukin-8 (IL-8), a chemokine that promotes tumor progression, immune escape, epithelial-mesenchymal transition, and recruitment of myeloid-derived suppressor cells. Studies have demonstrated that high serum IL-8 levels correlate with poor prognosis in many malignant tumors. Preclinical studies have shown that IL-8 blockade may reduce mesenchymal features in tumor cells, making them less resistant to treatment.

METHODS

Fifteen patients with metastatic or unresectable locally advanced solid tumors were enrolled in this 3 + 3 dose-escalation trial at four dose levels (4, 8, 16, or 32 mg/kg). HuMax-IL8 was given IV every 2 weeks, and patients were followed for safety and immune monitoring at defined intervals up to 52 weeks.

RESULTS

All enrolled patients (five chordoma, four colorectal, two prostate, and one each of ovarian, papillary thyroid, chondrosarcoma, and esophageal) received at least one dose of HuMax-IL8. Eight patients had received three or more prior lines of therapy and five patients had received prior immunotherapy. Treatment-related adverse events occurred in five patients (33%), mostly grade 1. Two patients receiving the 32 mg/kg dose had grade 2 fatigue, hypophosphatemia, and hypersomnia. No dose-limiting toxicities were observed, and maximum tolerated dose was not reached. Although no objective tumor responses were observed, 11 patients (73%) had stable disease with median treatment duration of 24 weeks (range, 4-54 weeks). Serum IL-8 was significantly reduced on day 3 of HuMax-IL8 treatment compared to baseline (p = 0.0004), with reductions in IL-8 seen at all dose levels.

CONCLUSIONS

HuMax-IL8 is safe and well-tolerated. Ongoing studies are evaluating the combination of IL-8 blockade and other immunotherapies.

TRIAL REGISTRATION

NCTN, NCT02536469. Registered 23 August 2015, https://clinicaltrials.gov/ct2/show/NCT02536469?term=NCT02536469&rank=1 .

Neutralization of IL-8 decreases tumor PMN-MDSCs and reduces mesenchymalization of claudin-low triple-negative breast cancer

The complex signaling networks of the tumor microenvironment that facilitate tumor growth and progression toward metastatic disease are becoming a focus of potential therapeutic options. The chemokine IL-8 is overexpressed in multiple cancer types, including triple-negative breast cancer (TNBC), where it promotes the acquisition of mesenchymal features, stemness, resistance to therapies, and the recruitment of immune-suppressive cells to the tumor site. The present study explores the utility of a clinical-stage monoclonal antibody that neutralizes IL-8 (HuMax-IL8) as a potential therapeutic option for TNBC. HuMax-IL8 was shown to revert mesenchymalization in claudin-low TNBC models both in vitro and in vivo as well as to significantly decrease the recruitment of polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) at the tumor site, an effect substantiated when used in combination with docetaxel. In addition, HuMax-IL8 enhanced the susceptibility of claudin-low breast cancer cells to immune-mediated lysis with NK and antigen-specific T cells in vitro. These results demonstrate the multifaceted way in which neutralizing this single chemokine reverts mesenchymalization, decreases recruitment of MDSCs at the tumor site, assists in immune-mediated killing, and forms the rationale for using HuMax-IL8 in combination with chemotherapy or immune-based therapies for the treatment of TNBC.

Inflammatory Cytokines as Uremic Toxins: "Ni Son Todos Los Que Estan, Ni Estan Todos Los Que Son"

Chronic kidney disease is among the fastest growing causes of death worldwide. An increased risk of all-cause and cardiovascular death is thought to depend on the accumulation of uremic toxins when glomerular filtration rate falls. In addition, the circulating levels of several markers of inflammation predict mortality in patients with chronic kidney disease. Indeed, a number of cytokines are listed in databases of uremic toxins and uremic retention solutes. They include inflammatory cytokines (IL-1β, IL-18, IL-6, TNFα), chemokines (IL-8), and adipokines (adiponectin, leptin and resistin), as well as anti-inflammatory cytokines (IL-10). We now critically review the cytokines that may be considered uremic toxins. We discuss the rationale to consider them uremic toxins (mechanisms underlying the increased serum levels and evidence supporting their contribution to CKD manifestations), identify gaps in knowledge, discuss potential therapeutic implications to be tested in clinical trials in order to make this knowledge useful for the practicing physician, and identify additional cytokines, cytokine receptors and chemokines that may fulfill the criteria to be considered uremic toxins, such as sIL-6R, sTNFR1, sTNFR2, IL-2, CXCL12, CX3CL1 and others. In addition, we suggest that IL-10, leptin, adiponectin and resistin should not be considered uremic toxins toxins based on insufficient or contradictory evidence of an association with adverse outcomes in humans or preclinical data not consistent with a causal association.

The strange connection between epidermal growth factor receptor tyrosine kinase inhibitors and dapsone: from rash mitigation to the increase in anti-tumor activity

The presence of an aberrantly activated epidermal growth factor receptor (EGFR) in many epithelial tumors, due to its overexpression, activating mutations, gene amplification and/or overexpression of receptor ligands, represent the fundamental basis underlying the use of EGFR tyrosine kinase inhibitors (EGFR-TKIs). Drugs inhibiting the EGFR have different mechanisms of action; while erlotinib and gefitinib inhibit the intracellular tyrosine kinase, monoclonal antibodies like cetuximab and panitumumab bind the extracellular domain of the EGFR both activating immunomediated anti-cancer effect and inhibiting receptor function. On the other hand, interleukin-8 has tumor promoting as well as neo-angiogenesis enhancing effects and several attempts have been made to inhibit its activity. One of these is based on the use of the old sulfone antibiotic dapsone that has demonstrated several interleukin-8 system inhibiting actions. Erlotinib typically gives a rash that has recently been proven to come out via up-regulated keratinocyte interleukin-8 synthesis with histological features reminiscent of typical neutrophilic dermatoses. In this review, we report experimental evidence that shows the use of dapsone to improve quality of life in erlotinib-treated patients by ameliorating rash as well as short-circuiting a growth-enhancing aspect of erlotinib based on increased interleukin-8 secretion.

Biomarkers of skin toxicity induced by anti-epidermal growth factor receptor antibody treatment in colorectal cancer

Skin toxicity is a common symptom of anti-epidermal growth factor receptor (EGFR) antibody treatment and is also a predictive marker of its efficacy in colorectal cancer patients. However, severe skin disorders induced by such antibodies negatively impact on the quality of life of patients and decreases drug compliance during treatment. If we can predict the high-risk group susceptible to severe skin toxicity before treatment, we can undertake the early management of any arising skin disorders and formulate a more accurate prognosis for anti-EGFR antibody treatment. Previous studies have identified molecular markers of skin toxicity induced by anti-EGFR antibody, such as EGFR polymorphisms, the expression of inflammatory chemokines and serum levels of EGFR ligands. A clinical trial was undertaken involving the escalation of cetuximab doses, guided by the grade of skin toxicity observed, such as no or low-grade, in metastatic colorectal cancer (the EVEREST study). The dose escalation of cetuximab was confirmed by a safety profile and had the tendency to achieve a higher response rate in KRAS wild-type patients. A large, prospective randomized trial is now ongoing (EVEREST 2) and the results of this trial may contribute to personalized medicine in KRAS wild-type colorectal cancer patients.

Treponema pallidum (syphilis) antigen TpF1 induces angiogenesis through the activation of the IL-8 pathway

Over 10 million people every year become infected by Treponema pallidum and develop syphilis, a disease with broad symptomatology that, due to the difficulty to eradicate the pathogen from the highly vascularized secondary sites of infection, is still treated with injections of penicillin. Unlike most other bacterial pathogens, T. pallidum infection produces indeed a strong angiogenic response whose mechanism of activation, however, remains unknown. Here, we report that one of the major antigen of T. pallidum, the TpF1 protein, has growth factor-like activity on primary cultures of human endothelial cells and activates specific T cells able to promote tissue factor production. The growth factor-like activity is mediated by the secretion of IL-8 but not of VEGF, two known angiogenic factors. The pathogen’s factor signals IL-8 secretion through the activation of the CREB/NF-κB signalling pathway. These findings are recapitulated in an animal model, zebrafish, where we observed that TpF1 injection stimulates angiogenesis and IL-8, but not VEGF, secretion. This study suggests that the angiogenic response observed during secondary syphilis is triggered by TpF1 and that pharmacological therapies directed to inhibit IL-8 response in patients should be explored to treat this disease.

Erlotinib augmentation with dapsone for rash mitigation and increased anti-cancer effectiveness

BACKGROUND

The epidermal growth factor receptor tyrosine kinase inhibitor erlotinib has failed in many ways to be as potent in the anti-cancer role as pre-clinical studies would have suggested. This paper traces some aspects of this failure to a compensatory erlotinib-mediated increase in interleukin-8. Many other-but not all- cancer chemotherapeutic cytotoxic drugs also provoke a compensatory increase in a malignant clone's interleukin-8 synthesis. Untreated glioblastoma and other cancer cells themselves natively synthesize interleukin-8. Interleukin-8 has tumor growth promoting, mobility and metastasis formation enhancing, effects as well as pro-angiogenesis effects.

FINDINGS

The old sulfone antibiotic dapsone- one of the very first antibiotics in clinical use- has demonstrated several interleukin-8 system inhibiting actions. Review of these indicates dapsone has potential to augment erlotinib effectiveness. Erlotinib typically gives a rash that has recently been proven to come about via an erlotinib triggered up-regulated keratinocyte interleukin-8 synthesis. The erlotinib rash shares histological features reminiscent of typical neutrophilic dermatoses. Dapsone has an established therapeutic role in current treatment of other neutrophilic dermatoses.

CONCLUSION

Thus, dapsone has potential to both improve the quality of life in erlotinib treated patients by amelioration of rash as well as to short-circuit a growth-enhancing aspect of erlotinib when used in the anti-cancer role.

High-throughput screening identified inherited genetic variations in the EGFR pathway contributing to skin toxicity of EGFR inhibitors

Aim: To identify genomic variants in the EGFR pathway and in cytokines predisposing to skin toxicity from EGFR inhibitors. Patients & methods: In 126 patients with cancer and EGFR inhibitor therapy skin toxicity was quantified and EGFR and inflammatory pathway genes were analyzed by deep sequencing. Results: We found 1437 SNPs in the 382-kb target region. Three SNPs in EGFR intron 1 were found exclusively in patients without skin rash. Another EGFR intron 23 SNP was associated with skin rash, overall survival and IL8 plasma concentrations. Moreover, carriers of the PIK3R1 326I variant were predisposed to skin rash and better survival. Conclusion: Comprehensive pathway-based resequencing revealed some new but only moderately strong genomic predictors of skin toxicity.

Mechanisms underlying skin disorders induced by EGFR inhibitors

The epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase that is frequently mutated or overexpressed in a large number of tumors such as carcinomas or glioblastoma. Inhibitors of EGFR activation have been successfully established for the therapy of some cancers and are more and more frequently being used as first or later line therapies. Although the side effects induced by inhibitors of EGFR are less severe than those observed with classic cytotoxic chemotherapy and can usually be handled by out-patient care, they may still be a cause for dose reduction or discontinuation of treatment that can reduce the effectiveness of antitumor therapy. The mechanisms underlying these cutaneous side effects are only partly understood. Important questions, such as the reasons for the correlation between the intensity of the side effects and the efficiency of treatment with EGFR inhibitors, remain to be answered. Optimized adjuvant strategies to accompany anti-EGFR therapy need to be found for optimal therapeutic application and improved quality of life of patients. Here, we summarize current literature on the molecular and cellular mechanisms underlying the cutaneous side effects induced by EGFR inhibitors and provide evidence that keratinocytes are probably the optimal targets for adjuvant therapy aimed at alleviating skin toxicities.

Cutaneous adverse effects of targeted therapies: Part I: Inhibitors of the cellular membrane

There has been a rapid emergence of numerous targeted agents in the oncology community in the last decade. This exciting paradigm shift in drug development lends promise for the future of individualized medicine. Given the pace of development and clinical deployment of targeted agents with novel mechanisms of action, dermatology providers may not be familiar with the full spectrum of associated skin-related toxicities. Cutaneous adverse effects are among the most frequently observed toxicities with many targeted agents, and their intensity can be dose-limiting or lead to therapy discontinuation. In light of the often life-saving nature of emerging oncotherapeutics, it is critical that dermatologists both understand the mechanisms and recognize clinical signs and symptoms of such toxicities in order to provide effective clinical management. Part I of this continuing medical education article will review in detail the potential skin-related adverse sequelae, the frequency of occurrence, and the implications associated with on- and off-target cutaneous toxicities of inhibitors acting at the cell membrane level, chiefly inhibitors of epidermal growth factor receptor, KIT, and BCR-ABL, angiogenesis, and multikinase inhibitors.

Cytokine regulation by epidermal growth factor receptor inhibitors and epidermal growth factor receptor inhibitor associated skin toxicity in cancer patients

AIM

Epidermal growth factor receptor inhibitor (EGFRI) induced skin toxicity has a prognostic value suggesting skin toxicity can be a useful surrogate marker for successful epidermal growth factor receptor (EGFR) inhibition, improved response and survival. But the pathophysiology of EGFRI induced skin toxicity remains elusive. However the involvement of immunological mechanisms has been speculated. This study investigates the possible underlying mechanism of EGFR inhibition associated cytokine production in keratinocytes as well as in patients after treatment with epidermal growth factor receptor inhibitors (EGFRIs).

METHODS

Normal human epidermal keratinocytes (NHEK) were incubated for 2 and 24h with different concentrations of EGFRI (erlotinib) for Western blot analysis and cytokine expression analysis, respectively. Inhibition of EGFR, extracellular-signal-regulated kinase 1/2 (Erk 1/2) and c-Jun was examined by Western blot analysis. Cytokine concentrations were measured by enzyme-linked immunosorbent assay (ELISA) in the NHEK cell supernatant and also in the serum of 186 cancer patients who are followed up for EGFRI induced skin rash.

RESULTS

A significant inhibitory effect of EGFRI was seen on EGFR (Y845), Erk 1/2 and c-Jun in a dose dependent manner. Further downstream, increased CC-chemokine ligand 2 (CCL2), CC-chemokine ligand 5 (CCL5) and decreased interleukin-8 (IL-8) or CXCL8 expression was observed in keratinocytes. In EGFRI treated patients, low levels of serum CXCL8 corresponding to stronger EGFR inhibition were associated with a higher grade of skin toxicity (p=0.0016) and a prolonged overall survival (p=0.018).

CONCLUSIONS

The results obtained in this study indicate that EGFRI can regulate cytokines by modulating EGFR signalling pathway in keratinocytes. Moreover, serum levels of CXCL8 in EGFRI treated patients may be important for individual EGFRI induced skin toxicity and patient's survival.