Targeting the epidermal growth factor receptor in solid tumors: focus on safety

Recent advances in multitarget-directed ligands via in silico drug discovery

To combat multifactorial refractory diseases, such as cancer, cardiovascular, and neurodegenerative diseases, multitarget drugs have become an emerging area of research aimed at 'synthetic lethality' (SL) relationships associated with drug-resistance mechanisms. In this review, we discuss the in silico design of dual and triple-targeted ligands, strategies by which specific 'warhead' groups are incorporated into a parent compound or scaffold with primary inhibitory activity against one target to develop one small molecule that inhibits two or three molecular targets in an effort to increase potency against multifactorial diseases. We also discuss the analytical exploration of structure-activity relationships (SARs), physicochemical properties, polypharmacology, scaffold feature extraction of US Food and Drug Administration (FDA)-approved multikinase inhibitors (MKIs), and updates regarding the clinical status of dual-targeted chemotypes.

Discovery of BGB-8035, a Highly Selective Covalent Inhibitor of Bruton's Tyrosine Kinase for B-Cell Malignancies and Autoimmune Diseases

Bruton's tyrosine kinase (BTK) plays an essential role in B-cell receptor (BCR)-mediated signaling as well as the downstream signaling pathway for Fc receptors (FcRs). Targeting BTK for B-cell malignancies by interfering with BCR signaling has been clinically validated by some covalent inhibitors, but suboptimal kinase selectivity may lead to some adverse effects, which also makes the clinical development of autoimmune disease therapy more challenging. The structure-activity relationship (SAR) starting from zanubrutinib (BGB-3111) leads to a series of highly selective BTK inhibitors, in which BGB-8035 is located in the ATP binding pocket and has similar hinge binding to ATP but exhibits high selectivity over other kinases (EGFR, Tec, etc.). With an excellent pharmacokinetic profile as well as demonstrated efficacy studies in oncology and autoimmune disease models, BGB-8035 has been declared a preclinical candidate. However, BGB-8035 showed an inferior toxicity profile compared to that of BGB-3111.

Results of the phase IIa study to evaluate the efficacy and safety of rezivertinib (BPI-7711) for the first-line treatment of locally advanced or metastatic/recurrent NSCLC patients with EGFR mutation from a phase I/IIa study

BACKGROUND

Rezivertinib (BPI-7711) is a novel third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI). This phase IIa study was part of a phase I/IIa study (NCT03386955), aimed to evaluate the efficacy and safety of rezivertinib as the first-line treatment for patients with locally advanced or metastatic/recurrent EGFR mutated non-small cell lung cancer (NSCLC).

METHODS

Patients received the first-line treatment of 180 mg rezivertinib orally once daily until disease progression, unacceptable toxicity, or withdrawal of consent. The primary endpoint was the objective response rate (ORR) assessed by blinded independent central review (BICR). Secondary endpoints included disease control rate (DCR), duration of response (DoR), progression-free survival (PFS), overall survival (OS), and safety.

RESULTS

From Jun 12, 2019, to Oct 17, 2019, 43 patients were enrolled. At the data cutoff date on Dec 23, 2021, the ORR by BICR was 83.7% (95% CI: 69.3-93.2%). The median DoR was 19.3 (95% CI: 15.8-25.0) months. The median PFS by BICR was 20.7 (95% CI: 13.8-24.8) months and 22.0 (95% CI: 16.8-26.3) months by investigators. Data on OS was immature. Totally, 40 (93.0%) patients had at least one treatment-related adverse event while 4 (9.3%) of them were grade ≥ 3.

CONCLUSIONS

Rezivertinib (BPI-7711) showed promising efficacy and a favorable safety profile for the treatment among the locally advanced or metastatic/recurrent NSCLC patients with EGFR mutation in the first-line setting.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03386955.

Gastrointestinal injury induced by immunomodulators: A review article

An increasing number of immunomodulators, either anti-inflammatory or immunity-enhancing, have brought about a revolutionary effect in the management of a variety of autoimmune disorders and malignancies. However, their ability to cause gastrointestinal (GI) injury and induce GI symptoms has been increasingly and unexpectedly recognized. GI injury associated with immunomodulators may demonstrate various histologic and endoscopic patterns. Optimal diagnosis and treatment require a multidisciplinary approach. This review aims to provide an overview of the literature on its pathogenesis, the clinical, endoscopic, and histologic features, and suggested approaches to manage these newly recognized immunomodulator-induced GI adverse effects (AEs). We also reviewed current biomarkers predictive of GI toxicity and potential risk factors to identify susceptible patients. In addition, these immune-mediated AEs were compared with inflammatory bowel disease, a well-documented form of inflammation-driven GI injury. We hope this review will raise awareness and vigilance among clinicians of these entities to increase early diagnosis and rapid referral to specialist care.

Combination Use of First-Line Afatinib and Proton-Pump Inhibitors Reduces Overall Survival Among Patients with EGFFR Mutant Lung Cancer

Purpose

Previous retrospective studies reported that proton-pump inhibitors (PPIs) may decrease the efficacy of first-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) including gefitinib and erlotinib. Afatinib had a wider soluble pH range, with possible fewer interactions with antacids. However, clinical data were limited. Thus, this study aimed to evaluate the negative impact of PPIs on afatinib.

Patients and Methods

This retrospective cohort study included patients who are newly diagnosed with non-small cell lung cancer (NSCLC) from 2014 to 2019 using the Chang Gung Research Database. We identified patients who were treated with first-line afatinib and analyzed the association between the PPI and afatinib treatment outcomes.

Results

A total of 1418 patients were treated with first-line afatinib and followed up for 6 years. First-line afatinib was administered to 918 eligible patients, and 330 had afatinib with PPIs. The combination use of PPIs and afatinib significantly decreased the overall survival (OS) compared with that of patients using afatinib only (median OS: 33.2 and 25.1 months, p < 0.01) and multivariate analyses (Combination use: hazard ratio: 1.29; 1.05-1.59, p = 0.01). The percentages of patients who were able to receive 2nd line therapy also significantly decreased in afatinib with PPI cohort.

Conclusion

The concurrent use of PPIs was associated with lower OS in patients with EGFR-mutant lung cancer under the first-line afatinib treatment but not associated with TTF.

Hypoxia-regulated microRNAs: the molecular drivers of tumor progression

Hypoxia is a common feature of the tumor microenvironment (TME) of nearly all solid tumors, leading to therapeutic failure. The changes in stiffness of the extracellular matrix (ECM), pH gradients, and chemical balance that contribute to multiple cancer hallmarks are closely regulated by intratumoral oxygen tension via its primary mediators, hypoxia-inducible factors (HIFs). HIFs, especially HIF-1α, influence these changes in the TME by regulating vital cancer-associated signaling pathways and cellular processes including MAPK/ERK, NF-κB, STAT3, PI3K/Akt, Wnt, p53, and glycolysis. Interestingly, research has revealed the involvement of epigenetic regulation by hypoxia-regulated microRNAs (HRMs) of downstream target genes involved in these signaling. Through literature search and analysis, we identified 48 HRMs that have a functional role in the regulation of 5 key cellular processes: proliferation, metabolism, survival, invasion and migration, and immunoregulation in various cancers in hypoxic condition. Among these HRMs, 17 were identified to be directly associated with HIFs which include miR-135b, miR-145, miR-155, miR-181a, miR-182, miR-210, miR-224, miR-301a, and miR-675-5p as oncomiRNAs, and miR-100-5p, miR-138, miR-138-5p, miR-153, miR-22, miR-338-3p, miR-519d-3p, and miR-548an as tumor suppressor miRNAs. These HRMs serve as a potential lead in the development of miRNA-based targeted therapy for advanced solid tumors. Future development of combined HIF-targeted and miRNA-targeted therapy is possible, which requires comprehensive profiling of HIFs-HRMs regulatory network, and improved formula of the delivery vehicles to enhance the therapeutic kinetics of the targeted cancer therapy (TCT) moving forward.

Two-year outcomes of tirabrutinib monotherapy in Waldenström's macroglobulinemia

The phase II study of tirabrutinib monotherapy at a daily dose of 480 mg under fasted conditions for treatment-naïve and relapsed/refractory Waldenström's macroglobulinemia (ONO-4059-05 study) demonstrated a promising efficacy and tolerable safety profile. We conducted an unplanned analysis with a median follow-up of 24.8 months to update the efficacy and safety results and to report patient-reported quality of life. Of 27 enrolled patients, 22 patients continued receiving the study drug. The major response assessed by an independent review committee was observed in 25 patients (93%), including 1 and 5 patients who newly achieved complete response and very good partial response, respectively, after the primary analysis. The progression-free and overall survival rates at 24 months were 92.6% and 100%, respectively. Serum IgM levels in all patients except one declined and were maintained at low levels although transient increases occurred after temporal interruption of the study drug. The disease-related symptoms including recurrent fever and hyperviscosity mostly disappeared. Health-related quality of life, assessed by cancer-specific questionnaires, was mostly maintained. Grade 3-4 neutropenia, lymphopenia, and leukopenia were newly recognized in three, two, and one patient, respectively. Grade 3 treatment-related hypertriglyceridemia was also recognized. Nine patients experienced grade 1-2 bleeding events (33%), one patient experienced grade 2 treatment-related atrial fibrillation, and one patient experienced grade 1 treatment-related hypertension. Treatment-related skin adverse events were observed in 14 patients (52%). Taken together, tirabrutinib has durable efficacy with an acceptable safety profile for treatment-naïve and refractory/relapsed Waldenström's macroglobulinemia.

Tucatinib: an investigational novel therapeutic agent for the treatment of HER-2 colorectal cancer

INTRODUCTION

Human epidermal growth factor receptor 2 (HER-2) is an oncogenic driver and target in gastroesophageal and breast cancer; there is also evidence for a role in non-small cell lung cancer (NSCLC). In colorectal cancer (CRC), the incidence of HER-2 overexpression occurs in up to 10% of patients. While its role of HER-2 as a biomarker for prognosis in CRC remains uncertain, it remains of interest as a potential therapeutic target. Tucatinib is an investigational agent which functions as a selective HER-2 inhibitor.

AREAS COVERED

In this article, the authors discuss the incidence of HER-2 in CRC and its rationale in the treatment of CRC. An overview of the market is offered, followed by a scientific summary of tucatinib including its clinical development in CRC.

EXPERT OPINION

Tucatinib is a selective HER-2 inhibitor that has unique properties which distinguishes it from other HER-2 directed therapies. In the clinical setting, it has demonstrated clinical efficacy of HER-2 inhibition across various solid tumors including CRC. Given the evidence of clinical activity observed with tucatinib in breast cancer and frequency of HER-2 overexpression in CRC, the investigation of tucatinib as a monotherapy and in combination with other therapeutic agents remains of interest.

Discovery of pyrido[3,4-b]indol-1-one derivatives as novel non-covalent Bruton's tyrosine kinase (BTK) inhibitors

Bruton's tyrosine kinase (BTK) is an attractive target for the treatment of malignancy and inflammatory/autoimmune diseases. Most of the covalent BTK inhibitors would induce off-target side effects and drug resistance. To improve the drug safety of BTK inhibitors, non-covalent inhibitors have attracted more and more attention. We designed a series of novel pyrido[3,4-b]indol-1-one derivatives (N-A and N-B) via scaffold hopping from CGI-1746. The structure-activity relationship (SAR) of the newly-synthesized compounds was explored. The results showed that compounds 12 and 18 exhibited potent enzymatic potency against BTK with IC₅₀ values of 0.22 μM and 0.19 μM, respectively. In lymphoma cell lines U-937 cells and Ramos cells, compounds 12 and 18 displayed comparative antiproliferative activity with Ibrutinib. Moreover, compound 12 induced G1-phase cell cycle arrest and apoptosis in U-937 cells. And it could effectively inhibit tumor growth in U-937 xenograft mouse model (TGI = 41.90% at 50 mg/kg). In all, the new pyrido[3,4-b]indol-1-one derivatives have the antitumor potency by BTK inhibition and were worthy of further exploration.

Small Molecule Kinase Inhibitor Drugs (1995-2021): Medical Indication, Pharmacology, and Synthesis

The central role of dysregulated kinase activity in the etiology of progressive disorders, including cancer, has fostered incremental efforts on drug discovery programs over the past 40 years. As a result, kinase inhibitors are today one of the most important classes of drugs. The FDA approved 73 small molecule kinase inhibitor drugs until September 2021, and additional inhibitors were approved by other regulatory agencies during that time. To complement the published literature on clinical kinase inhibitors, we have prepared a review that recaps this large data set into an accessible format for the medicinal chemistry community. Along with the therapeutic and pharmacological properties of each kinase inhibitor approved across the world until 2020, we provide the synthesis routes originally used during the discovery phase, many of which were only available in patent applications. In the last section, we also provide an update on kinase inhibitor drugs approved in 2021.

Bio-vehicles of cytotoxic drugs for delivery to tumor specific targets for cancer precision therapy

Abnormal structural and molecular changes in malignant tissues were thoroughly investigated and utilized to target tumor cells, hence rescuing normal healthy tissues and lowering the unwanted side effects as non-specific cytotoxicity. Various ligands for cancer cell specific markers have been uncovered and inspected for directional delivery of the anti-cancer drug to the tumor site, in addition to diagnostic applications. Over the past few decades research related to the ligand targeted therapy (LTT) increased tremendously aiming to treat various pathologies, mainly cancers with well exclusive markers. Malignant tumors are known to induce elevated levels of a variety of proteins and peptides known as cancer "markers" as certain antigens (e.g., Prostate specific membrane antigen "PSMA", carcinoembryonic antigen "CEA"), receptors (folate receptor, somatostatin receptor), integrins (Integrin αvβ3) and cluster of differentiation molecules (CD13). The choice of an appropriate marker to be targeted and the design of effective ligand-drug conjugate all has to be carefully selected to generate the required therapeutic effect. Moreover, since some tumors express aberrantly high levels of more than one marker, some approaches investigated targeting cancer cells with more than one ligand (dual or multi targeting). We aim in this review to report an update on the cancer-specific receptors and the vehicles to deliver cytotoxic drugs, including recent advancements on nano delivery systems and their implementation in targeted cancer therapy. We will discuss the advantages and limitations facing this approach and possible solutions to mitigate these obstacles. To achieve the said aim a literature search in electronic data bases (PubMed and others) using keywords "Cancer specific receptors, cancer specific antibody, tumor specific peptide carriers, cancer overexpressed proteins, gold nanotechnology and gold nanoparticles in cancer treatment" was carried out.

Comparative Analysis of BTK Inhibitors and Mechanisms Underlying Adverse Effects

The cytoplasmic protein-tyrosine kinase BTK plays an essential role for differentiation and survival of B-lineage cells and, hence, represents a suitable drug target. The number of BTK inhibitors (BTKis) in the clinic has increased considerably and currently amounts to at least 22. First-in-class was ibrutinib, an irreversible binder forming a covalent bond to a cysteine in the catalytic region of the kinase, for which we have identified 228 active trials listed at ClinicalTrials.gov. Next-generation inhibitors, acalabrutinib and zanubrutinib, are approved both in the United States and in Europe, and zanubrutinib also in China, while tirabrutinib is currently only registered in Japan. In most cases, these compounds have been used for the treatment of B-lymphocyte tumors. However, an increasing number of trials instead addresses autoimmunity and inflammation in multiple sclerosis, rheumatoid arthritis, pemphigus and systemic lupus erythematosus with the use of either irreversibly binding inhibitors, e.g., evobrutinib and tolebrutinib, or reversibly binding inhibitors, like fenebrutinib. Adverse effects (AEs) have predominantly implicated inhibition of other kinases with a BTKi-binding cysteine in their catalytic domain. Analysis of the reported AEs suggests that ibrutinib-associated atrial fibrillation is caused by binding to ERBB2/HER2 and ERBB4/HER4. However, the binding pattern of BTKis to various additional kinases does not correlate with the common assumption that skin manifestations and diarrhoeas are off-target effects related to EGF receptor inhibition. Moreover, dermatological toxicities, diarrhoea, bleedings and invasive fungal infections often develop early after BTKi treatment initiation and subsequently subside. Conversely, cardiovascular AEs, like hypertension and various forms of heart disease, often persist.

Targeted Therapy- and Chemotherapy-Associated Skin Toxicities: Systematic Review and Meta-Analysis

PROBLEM IDENTIFICATION

Preventing and managing skin toxicities can minimize treatment disruptions and improve well-being. This systematic review aimed to evaluate the effectiveness of interventions for the prevention and management of cancer treatment-related skin toxicities.

LITERATURE SEARCH

The authors systematically searched for comparative studies published before April 1, 2019. Study selection and appraisal were conducted by pairs of independent reviewers.

DATA EVALUATION

The random-effects model was used to conduct meta-analysis when appropriate.

SYNTHESIS

39 studies (6,006 patients) were included; 16 of those provided data for meta-analysis. Prophylactic minocycline reduced the development of all-grade and grade 1 acneform rash in patients who received erlotinib. Prophylaxis with pyridoxine 400 mg in capecitabine-treated patients lowered the risk of grade 2 or 3 hand-foot syndrome. Several treatments for hand-foot skin reaction suggested benefit in heterogeneous studies. Scalp cooling significantly reduced the risk for severe hair loss or total alopecia associated with chemotherapy.

IMPLICATIONS FOR RESEARCH

Certainty in the available evidence was limited for several interventions, suggesting the need for future research.

SUPPLEMENTAL MATERIAL CAN BE FOUND AT&NBSP;HTTPS

//onf.ons.org/supplementary-material-targeted-therapy-and-chemotherapy-associated-skin-toxicity-systematic-review.

Potential Successes and Challenges of Targeted Cancer Therapies

The concept and realization of targeted anticancer therapy (TAT) have existed for at least two decades and continue to expand rapidly. It has become clear that there is no "magic bullet" to cure cancer and that even TATs are unlikely to be successful as single agents, necessitating combination with chemotherapy, radiotherapy, or even other targeting agents. The other promise that has not been fulfilled by TAT is that of reduced toxicity. It was thought that by targeting receptors on or within cells, rather than particular phases of the cell cycle, TATs would not be toxic. However, it turns out that the targets also exist on or within normal cells and that there is even cross-reactivity between receptors on nontarget tissues. All of this results in toxicity, the mechanism of which are the same as the mechanism of action of the drugs, making toxicity reduction or prevention very difficult. This leads to new toxicities with new targeted treatments. Nevertheless, all of the above should not detract from the obvious successes of targeted agents, which have turned several acutely fatal cancers into chronic diseases and rendered some hitherto untreatable cancers into treatable diseases.

RN765C, a low affinity EGFR antibody drug conjugate with potent anti-tumor activity in preclinical solid tumor models

Epidermal growth factor receptor (EGFR) is a clinically validated target and often overexpressed in some solid tumors. Both EGFR tyrosine kinase inhibitors and ligand-blocking antibodies have been approved for treatment of NSCLC, head and neck cancers and colorectal cancers. However, clinical response is limited and often accompanied by significant toxicities due to normal tissue expression. To improve the effectiveness of targeting EGFR while minimizing the toxicities on normal tissues, we developed a low-affinity anti-EGFR antibody drug conjugate (ADC), RN765C. Potent in vitro cytotoxicity of RN765C, with nanomolar to subnanomolar EC50, was observed on a panel of cancer cell lines expressing moderate to high level of EGFR. In contrast, RN765C was less effective in killing normal human keratinocytes, presumably due to its lower receptor expression. Mechanistically, RN765C has multiple modes of action: inducing payload mediated mitotic arrest and cell death, blocking EGFR pathway signal and mediating antibody dependent cell cytotoxicity. In preclinical studies, a single dose of RN765C at 1.5-3 mg/kg was generally sufficient to induce tumor regression in multiple cell line and patient-derived xenograft models, including those that are resistant to EGFR-directed tyrosine kinase inhibitors. Our data support further investigation of RN765C in the clinic to treat EGFR expressing solid tumors.

Genomic alterations of ERBB receptors in cancer: clinical implications

The ERBB family of receptor tyrosine kinases has been implicated in carcinogenesis for over three decades with rigorous attention to EGFR and HER2. ERBB receptors, consisting of EGFR, HER2, HER3, and HER4 are part of a complicated signaling network that activates downstream signaling pathways including PI3K/AKT, Ras/Raf/MAPK, JAK/STAT and PKC. It is well established that EGFR is amplified and/or mutated in gliomas and non-small-cell lung carcinoma while HER2 is amplified and/or over-expressed in breast, gastric, ovarian, non-small cell lung carcinoma, and several other tumor types. With the advent of next generation sequencing and large scale efforts to explore the entire spectrum of genomic alterations involved in human cancer progression, it is now appreciated that somatic ERBB receptor mutations occur at relatively low frequencies across multiple tumor types. Some of these mutations may represent oncogenic driver events; clinical studies are underway to determine whether tumors harboring these alterations respond to small molecule EGFR/HER2 inhibitors. Recent evidence suggests that some somatic ERBB receptor mutations render resistance to FDA-approved EGFR and HER2 inhibitors. In this review, we focus on the landscape of genomic alterations of EGFR, HER2, HER3 and HER4 in cancer and the clinical implications for patients harboring these alterations.

Phase I Study of ONT-380, a HER2 Inhibitor, in Patients with HER2+-Advanced Solid Tumors, with an Expansion Cohort in HER2+ Metastatic Breast Cancer (MBC)

Purpose: ONT-380 (ARRY-380) is a potent and selective oral HER2 inhibitor. This Phase I study determined the MTD, pharmacokinetics (PK) and antitumor activity of ONT-380 in HER2-positive advanced solid tumors, with an expansion cohort of patients with HER2⁺ MBC.Experimental Design: ONT-380 was administered twice daily (BID) in continuous 28-day cycles. After a modified 3+3 dose-escalation design determined the MTD, the expansion cohort was enrolled. PK properties of ONT-380 and a metabolite were determined. Response was evaluated by Response Evaluation Criteria in Solid Tumors (RECIST).Results: Fifty patients received ONT-380 (escalation = 33; expansion = 17); 43 patients had HER2⁺ MBC. Median prior anticancer regimens = 5. Dose-limiting toxicities of increased transaminases occurred at 800 mg BID, thus 600 mg BID was the MTD. Common AEs were usually Grade 1/2 in severity and included nausea (56%), diarrhea (52%), fatigue (50%), vomiting (40%) constipation, pain in extremity and cough (20% each). 5 patients (19%) treated at MTD had grade 3 AEs (increased transaminases, rash, night sweats, anemia, and hypokalemia). The half-life of ONT-380 was 5.38 hours and increases in exposure were approximately dose proportional. In evaluable HER2⁺ MBC (n = 22) treated at doses ≥ MTD, the response rate was 14% [all partial response (PR)] and the clinical benefit rate (PR + stable disease ≥ 24 weeks) was 27%.Conclusions: ONT-380 had a lower incidence and severity of diarrhea and rash than that typically associated with current dual HER2/EGFR inhibitors and showed notable antitumor activity in heavily pretreated HER2⁺ MBC patients, supporting its continued development. Clin Cancer Res; 23(14); 3529-36. ©2017 AACR.

Nursing Management of Cutaneous Toxicities From Epidermal Growth Factor Receptor Inhibitors

BACKGROUND

Personalized targeted therapies have become an emerging paradigm in cancer treatment. Although generally more tolerable than other chemotherapeutic agents, one therapy, epidermal growth factor receptor inhibitors (EGFRIs), commonly results in the formation of cutaneous toxicities, which can negatively affect patients' treatment adherence and quality of life.

OBJECTIVES

The aim of this article is to review nursing management strategies for EGFRI-related cutaneous toxicities.

METHODS

A systematic literature review was performed, including database searches in PubMed/MEDLINE®, CINAHL®, Cochrane Library, PsycINFO®, and Web of Science.

FINDINGS

Nurses are essential to the management of EGFRI-related cutaneous toxicities and are in an ideal position to provide supportive care throughout the course of the EGFRI treatment. The aim of nursing management is to maintain patients' treatment adherence and quality of life by employing a preemptive and proactive approach. Patient education is the most frequently reported management strategy. However, treatment options and management strategies are largely anecdotal and based on individual reports and expert opinions. Although no evidence-based management strategies exist, nurses can rely on existing assessment tools and guidelines to provide patients with symptom management and supportive care.

A prospective clinical trial to assess lapatinib effects on cutaneous squamous cell carcinoma and actinic keratosis

BACKGROUND

Antiepidermal growth factor receptor (EGFR)-targeted therapy is widely used in many epithelial cancer types. We investigated lapatinib effects on cutaneous squamous cell carcinoma (cSCC) scheduled for resection and in coexisting precursor lesions (actinic keratosis (AK) and Bowen's disease (BD)) in a phase 2 mode of action clinical trial including a histological workup of the cSCC.

PATIENTS AND METHODS

We initiated a prospective single-centre, open-label, non-controlled clinical study with translational intentions to investigate changes in size and histopathological features in cSCC after a 14-day period of neoadjuvant lapatinib therapy at a dose of 1500 mg/day prior to surgery, to quantify the impact on AK and BD in the same patient after 56 days and to evaluate the tolerability in patients with cSCC and precursor lesions.

RESULTS

10 immunocompetent male patients were included with a mean age of 73 years (range 59-87). 8 patients were treated with the study medication lapatinib 1500 mg/day for a total duration of 56 days according to the protocol and were available for full analysis, whereas 2 patients had to discontinue treatment during the first 2 weeks because of adverse events (diarrhoea, pancreatitis). Tolerability was acceptable with only 1 related grade III adverse event. A reduction in tumour size of cSCC was documented in 2 of 8 evaluable patients after 14 days of treatment. The mean regression of captured precursor lesions was 30% after 56 days of treatment and 36% 28 days after therapy cessation.

CONCLUSIONS

Short-term lapatinib resulted in a cSCC tumour reduction in 2 of 8 patients. In addition, there was a clinically documented reduction of AK in 7 of 8 patients encouraging larger clinical trials, especially in high-risk patients with cSCC such as organ transplant recipients.

TRIAL REGISTRATION NUMBER

NCT0166431.

A spectrum of cutaneous toxicities from erlotinib may be a robust clinical marker for non-small-cell lung therapy: a case report and literature review

Some literature suggests that an EGFR inhibition-induced rash can be used as a clinical marker, but few studies report the correlation between a spectrum of cutaneous toxicities from EGFR inhibition and drug efficacy. We report about a woman with a stage IV lung adenocarcinoma using erlotinib monotherapy, who experienced a spectrum of cutaneous toxicities, including papulopustular rash, mucositis, pruritus, xerosis, paronychia, and facial hirsutism. With treatment, her metastatic lesions shrunk remarkably. This report suggests that some non-small-cell lung cancer patients experiencing a spectrum of cutaneous toxicities might have a good tumor response using erlotinib monotherapy. Our findings may provide a method for clinicians to predict erlotinib efficacy in non-small-cell lung cancer therapy without knowledge of the EGFR mutation status.

An internal ribosome entry site in the 5' untranslated region of epidermal growth factor receptor allows hypoxic expression

The expression of epidermal growth factor receptor (EGFR/ERBB1/HER1) is implicated in the progress of numerous cancers, a feature that has been exploited in the development of EGFR antibodies and EGFR tyrosine kinase inhibitors as anti-cancer drugs. However, EGFR also has important normal cellular functions, leading to serious side effects when EGFR is inhibited. One damaging characteristic of many oncogenes is the ability to be expressed in the hypoxic conditions associated with the tumour interior. It has previously been demonstrated that expression of EGFR is maintained in hypoxic conditions via an unknown mechanism of translational control, despite global translation rates generally being attenuated under hypoxic conditions. In this report, we demonstrate that the human EGFR 5′ untranslated region (UTR) sequence can initiate the expression of a downstream open reading frame via an internal ribosome entry site (IRES). We show that this effect is not due to either cryptic promoter activity or splicing events. We have investigated the requirement of the EGFR IRES for eukaryotic initiation factor 4A (eIF4A), which is an RNA helicase responsible for processing RNA secondary structure as part of translation initiation. Treatment with hippuristanol (a potent inhibitor of eIF4A) caused a decrease in EGFR 5′ UTR-driven reporter activity and also a reduction in EGFR protein level. Importantly, we show that expression of a reporter gene under the control of the EGFR IRES is maintained under hypoxic conditions despite a fall in global translation rates.