Epidermal Growth Factor Receptor P753S Mutation in Cutaneous Squamous Cell Carcinoma Responsive to Cetuximab-Based Therapy

Immune checkpoint inhibitors with or without chemotherapy for orbital, conjunctival, and ocular adnexal squamous cell carcinoma

OBJECTIVE

Periocular squamous cell carcinoma (SCC) is relatively rare and presents unique anatomic considerations due to proximity to the eye and risk to ocular structures associated with high-dose radiation therapy or radical surgery. We present our observations in patients with periocular SCC treated with immune checkpoint inhibitor (ICI) therapy in an effort to decrease surgical morbidity or avoid high-dose radiation therapy.

METHODS

Retrospective review of patients with orbital, conjunctival, or periocular SCC who were treated with ICI either in the neoadjuvant setting prior to surgery or for treatment of perineural spread in the orbit/skull base.

RESULTS

Twelve men and 5 women with orbital (n = 6), conjunctival (n = 5), or lacrimal sac/duct (n = 2) SCC, or SCC with perineural spread (n = 4) were treated with ICI (cemiplimab or pembolizumab) either as single drug (n = 9) or combined with chemotherapy (n = 8). Overall, 5 patients achieved complete response, 8 patients achieved partial response, and 4 patients achieved stable disease, using the response evaluation criteria in solid tumors (RECIST) criteria. The objective response rate was 76.5%. In 12 patients ICI was used in the neoadjuvant setting prior to surgery. In 4 patients with perineural spread and unresectable disease, ICI was used to avoid high-dose radiation therapy. One additional patient with conjunctival SCC with nodal metastasis was treated with ICI alone and achieved a dramatic complete response and has thus far managed to avoid surgery altogether.

CONCLUSIONS

ICI either as single drug or in combination with chemotherapy has a high response rate in patients with periocular SCC. Future prospective trials should aim to correlate molecular data with response.

Cemiplimab for metastatic squamous cell carcinoma of the orbit, periocular adnexa, and thigh

The current case presentation highlights the potential of cemiplimab, a programmed cell death protein-1 (PD-1) inhibitor, as first-line treatment for periocular metastatic cutaneous squamous cell carcinoma (SCC) without requiring curative surgery or radiotherapy. A 64-year-old male presented with a progressing 4.5 × 3.0 cm left upper eyelid lesion initially diagnosed as psoriasis. Work-up revealed cutaneous SCC with tumor invasion into extraconal fat and lacrimal gland, and metastasis to the left parotid lymph node. The patient also presented with a suspicious lesion on his left medial thigh found to be a second primary on pathology. To avoid orbital exenteration and treat the multifocal disease, the patient was started on intravenous cemiplimab immunotherapy. Following six doses, repeated FGD-PET-CT revealed a complete response of the left eyelid lesion and residual low-grade hypermetabolic activity of the left medial thigh lesion. Biopsy confirmed chronic inflammation and fibrosis with no signs of malignancy. This unique case with dual primary cutaneous SCC provides support for cemiplimab in treating locally invasive periocular SCC, and potentially abrogating the need for highly morbid exenteration procedures to preserve binocular vision.

Design and Synthesis of Novel 2-Acetamido, 6-Carboxamide Substituted Benzothiazoles as Potential BRAFV600E Inhibitors - In vitro Evaluation of their Antiproliferative Activity

The oncogenic BRAFV600E kinase leads to abnormal activation of the MAPK signaling pathway and thus, uncontrolled cellular proliferation and cancer development. Based on our previous virtual screening studies which issued 2-acetamido-1,3 benzothiazole-6-carboxamide scaffold as active pharmacophore displaying selectivity against the mutated BRAF, eleven new substituted benzothiazole derivatives were designed and synthesized by coupling of 2-acetamidobenzo[d]thiazole-6-carboxylic acid with the appropriate amines in an effort to provide even more efficient inhibitors and tackle drug resistance often developed during cancer treatment. All derived compounds bore the benzothiazole scaffold substituted at position-2 by an acetamido moiety and at position-6 by a carboxamide functionality, the NH moiety of which was further linked through an alkylene linker to a sulfonamido (or amino) aryl (or alkyl) functionality or a phenylene linker to a sulfonamido aromatic (or non-aromatic) terminal pharmacophore in the order -C6 H4 -NHSO2 -R or reversely -C6 H4 -SO2 N(H)-R. These analogs were subsequently biologically evaluated as potential BRAFV600E inhibitors and antiproliferative agents in several colorectal cancer and melanoma cell lines. In all assays applied, one analog, namely 2-acetamido-N-[3-(pyridin-2-ylamino)propyl]benzo[d]thiazole-6-carboxamide (22), provided promising results in view of its use in drug development.

A pulmonary enteric adenocarcinoma patient harboring a rare EGFR exon 19 P753S mutation: Case report and review

Pulmonary enteric adenocarcinoma (PEAC) is a rare subtype of non–small cell lung cancer (NSCLC), accounting for about 0.6% of all primary lung adenocarcinoma. Although epidermal growth factor receptor (EGFR) mutation is common in primary lung adenocarcinoma, it is rarely reported in PEAC. This case report describes a PEAC patient with co-mutations of EGFR, Kirsten rat sarcoma viral oncogene (KRAS), and TP53, being treated with immunotherapy combined with chemotherapy. A 69-year-old man complained of cough and expectoration with bloody sputum for 2 weeks. The lung-enhanced CT scan showed a massive soft tissue shadow, about 46 × 35 mm in the lower lobe of the right lung. The neoplasm sample in the lower lobe of the right lung was obtained using CT-guided fine-needle aspiration (FNA). Immunohistochemical assays showed that the tumor was positive for CK7, CDX-2, C-MET, and villin. Gastroscopy and rectal colonoscopy had been performed respectively to exclude a diagnosis of colorectal adenocarcinoma. The patient was finally diagnosed with pulmonary intestinal adenocarcinoma. Next-generation sequencing (NGS) analysis showed a rare EGFR exon 19 missense mutation (c.2257C>T, p.P753S), KRAS exon 2 missense mutation (c.35G>T, p.G12V), and TP53 exon 5 missense mutation (c.401T>C, p.F134S). The lung-enhanced CT scan showed that the tumor shrank after four cycles of chemotherapy combined with immunotherapy. We hope that this case report can increase the understanding of this rare type of tumor and provide new molecular indications for diagnosis and individualized treatment. Furthermore, the combination of chemotherapy and immunotherapy seems to be an effective therapy for PEAC. Whether the use of immunotherapy can provide clinical benefits needs to be further explored with more samples in future studies.

High-throughput functional evaluation of human cancer-associated mutations using base editors

Comprehensive phenotypic characterization of the many mutations found in cancer tissues is one of the biggest challenges in cancer genomics. In this study, we evaluated the functional effects of 29,060 cancer-related transition mutations that result in protein variants on the survival and proliferation of non-tumorigenic lung cells using cytosine and adenine base editors and single guide RNA (sgRNA) libraries. By monitoring base editing efficiencies and outcomes using surrogate target sequences paired with sgRNA-encoding sequences on the lentiviral delivery construct, we identified sgRNAs that induced a single primary protein variant per sgRNA, enabling linking those mutations to the cellular phenotypes caused by base editing. The functions of the vast majority of the protein variants (28,458 variants, 98%) were classified as neutral or likely neutral; only 18 (0.06%) and 157 (0.5%) variants caused outgrowing and likely outgrowing phenotypes, respectively. We expect that our approach can be extended to more variants of unknown significance and other tumor types.

Multiplexed molecular profiling of lung cancer with malignant pleural effusion using next generation sequencing in Chinese patients

Lung cancer is the most common type of cancer and the leading cause of cancer-associated death worldwide. Malignant pleural effusion (MPE), which is observed in ~50% of advanced non-small cell lung cancer (NSCLC) cases, and most frequently in lung adenocarcinoma, is a common complication of stage III-IV NSCLC, and it can be used to predict a poor prognosis. In the present study, multiple oncogene mutations were detected, including 17 genes closely associated with initiation of advanced lung cancer, in 108 MPE samples using next generation sequencing (NGS). The NGS data of the present study had broader coverage, deeper sequencing depth and higher capture efficiency compared with NGS findings of previous studies on MPE. In the present study, using NGS, it was demonstrated that 93 patients (86%) harbored EGFR mutations and 62 patients possessed mutations in EGFR exons 18-21, which are targets of available treatment agents. EGFR L858R and exon 19 indel mutations were the most frequently observed alterations, with frequencies of 31 and 25%, respectively. In 1 patient, an EGFR amplification was identified and 6 patients possessed a T790M mutation. ALK + EML4 gene fusions were identified in 6 patients, a ROS1 + CD74 gene fusion was detected in 1 patient and 10 patients possessed a BIM (also known as BCL2L11) 2,903-bp intron deletion. In 4 patients, significant KRAS mutations (G12D, G12S, G13C and A146T) were observed, which are associated with resistance to afatinib, icotinib, erlotinib and gefitinib. There were 83 patients with ERBB2 mutations, but only two of these mutations were targets of available treatments. The results of the present study indicate that MPE is a reliable specimen for NGS based detection of somatic mutations.

Is high-risk cutaneous squamous cell carcinoma of the head and neck a suitable candidate for current targeted therapies?

OBJECTIVE

Cutaneous squamous cell carcinoma (cSCC) is the second most common malignancy, most frequently affecting the head and neck. Treatment often requires surgery and can have significant functional morbidity. Research into disease pathogenesis and second line medical management of cSCC is limited. We assess genetic mutations in high-risk, primary head and neck cutaneous squamous cell carcinomas (HNcSCC) that may hinder or be beneficial for use of targeted therapy in disease management.

METHODS

Genetic alterations and variant allele frequencies (VAFs) were analysed using a clinically relevant 48 gene panel in 10 primary high-risk non-metastatic treatment-naïve HNcSCC to evaluate applicability of targeted therapeutics. Variants present at all VAFs were evaluated for pathogenicity. Somatic mutation patterns of individual tumours were analysed.

RESULTS

High-risk HNcSCC showed a high proportion (82%) of C to T transitions in keeping with ultraviolet-mediated damage. There was significant intratumour genetic heterogeneity in this cohort (MATH scores 20-89) with the two patients <45 years of age showing highest intratumour heterogeneity. TP53 was altered at VAF >22% in all cases, and mutations with highest VAF were observed in tumour suppressor genes in 80%. 70% of cases demonstrated at least one mutation associated with treatment resistance (KIT S821F, KIT T670I, RAS mutations at codons 12 and 13).

CONCLUSION

We demonstrate high proportion tumour suppressor loss of function mutations, high intratumour genetic heterogeneity, and presence of well recognised resistance mutations in treatment naïve primary HNcSCC. These factors pose challenges for successful utilisation of targeted therapies.

New Vision in Photoprotection and Photorepair

Chronic exposure to solar radiation is associated with an increased incidence of skin cancer worldwide and more specifically with non-melanoma skin cancers and actinic keratosis. At the cellular level DNA damage is the main event following ultraviolet (UV) exposure. The kind of lesions produced depends on the wavelength and the energy profile of the radiation, with different photoproducts being formed as a result. Although endogenous DNA repair mechanisms are somewhat effective in repairing DNA, some DNA damage persists and can accumulate with chronic exposure. UV protection strategies, such as sunscreen use, are important in limiting further DNA damage. Several published studies have demonstrated the protective effect that regular use of sunscreen can have against the development of skin cancers. Newer options that aim to help repair damaged DNA may have an important role in reducing the incidence of chronic sun exposure-related photoaging and non-melanoma skin cancers. Photolyase, which is capable of repairing cyclobutane dimers formed as a result of DNA irradiation, is one such novel ingredient. In the first part of this paper we review the rationale for a combined treatment approach of photoprotection and photorepair with photolyase. In the second part we evaluate several published clinical studies, which suggest a beneficial effect in preventing new skin lesions in photodamaged skin. A strategy of photoprotection plus photorepair appears to be relevant for all persons with a high level of solar exposure and those at a higher risk for developing skin cancers.

Investigating mutation-specific biological activities of small molecules using quantitative structure-activity relationship for epidermal growth factor receptor in cancer

Epidermal Growth Factor Receptor (EGFR) is a potential drug target in cancer therapy. Missense mutations play major roles in influencing the protein function, leading to abnormal cell proliferation and tumorigenesis. A number of EGFR inhibitor molecules targeting ATP binding domain were developed for the past two decades. Unfortunately, they become inactive due to resistance caused by new mutations in patients, and previous studies have also reported noticeable differences in inhibitor binding to distinct known driver mutants as well. Hence, there is a high demand for identification of EGFR mutation-specific inhibitors. In our present study, we derived a set of anti-cancer compounds with biological activities against eight typical EGFR known driver mutations and developed quantitative structure-activity relationship (QSAR) models for each separately. The compounds are grouped based on their functional scaffolds, which enhanced the correlation between compound features and respective biological activities. The models for different mutants performed well with a correlation coefficient, (r) in the range of 0.72-0.91 on jack-knife test. Further, we analyzed the selected features in different models and observed that hydrogen bond and aromaticity-related features play important roles in predicting the biological activity of a compound. This analysis is complimented with docking studies, which showed the binding patterns and interactions of ligands with EGFR mutants that could influence their activities.

Molecular profiling of head and neck squamous cell carcinoma

Background

Head and neck squamous cell carcinoma (HNSCC) exhibits high rates of recurrence, and with few approved targeted agents, novel treatments are needed. We analyzed a molecular profiling database for the distribution of biomarkers predictive of chemotherapies and targeted agents.

Methods

Seven hundred thirty‐five patients with advanced HNSCC (88 with known human papillomavirus [HPV] status), were profiled using multiple platforms (gene sequencing, gene copy number, and protein expression).

Results

Among the entire patient population studied, epidermal growth factor receptor (EGFR) was the protein most often overexpressed (90%), TP53 gene most often mutated (41%), and phosphatidylinositol 3‐kinase (PIK3CA) most often amplified (40%; n = 5). With the exception of TP53 mutation, other biomarker frequencies were not significantly different among HPV‐positive or HPV‐negative patients. PIK3CA mutations and phosphatase and tensin homolog (PTEN) loss are frequent events, independent of HPV status. The immune response‐modulating programmed cell death 1 (PD1) and programmed cell death ligand 1 (PDL1) axis was active across sites, stages, and HPV status.

Conclusion

Molecular profiling utilizing multiple platforms provides a range of therapy options beyond standard of care. © 2015 Wiley Periodicals, Inc. Head Neck38: E1625–E1638, 2016

Comparison of uncommon EGFR exon 21 L858R compound mutations with single mutation

Non-small-cell lung cancer with epidermal growth factor receptor (EGFR) mutation is sensitive to EGFR tyrosine kinase inhibitors (TKIs). But little is known about the response to EGFR TKIs and the prognostic role of compound mutations. This study compared the uncommon EGFR exon 21 L858R compound mutations with single mutation to characterize EGFR compound mutations and investigated their response to EGFR TKI treatment. We retrospectively screened 799 non-small-cell lung cancer patients from August 1, 2009 to June 1, 2012 by EGFR mutation testing. EGFR mutations were detected in 443 patients, with 22 (4.97%) compound mutations. Subsequently, six patients with EGFR exon 21 L858R compound mutations and 18 paired patients with single L858R mutation were well characterized. Finally, we also analyzed the EGFR TKI treatment response and patients’ outcomes of compound or single L858R mutations. There was no differential treatment effect on the disease control rate and objective response rate between the L858R compound mutations and single mutation groups. No significant difference in overall survival or progression-free survival of these two groups was found by log-rank test. In conclusion, we demonstrated that no significant difference was detected in the response to EGFR TKIs and patients’ outcomes in the compound and single mutation groups.