Type of TP53 mutation influences oncogenic potential and spectrum of associated K-ras mutations in lung-specific transgenic mice

TP53 and K-ras mutations are two of the major genetic alterations in human nonsmall cell lung cancers. The association between these two genes during lung tumorigenesis is unknown. We evaluated the potential of two common Type I (273H, contact) and Type II (175H, conformational) TP53 mutations to induce lung tumors in transgenic mice, as well as K-ras status, and other driver mutations in these tumors. Among 516 (138 nontransgenic, 207 SPC-TP53-273H, 171 SPC-TP53-175H) mice analyzed, 91 tumors, all adenocarcinomas, were observed. Type II mutants developed tumors more frequently (as compared to nontransgenics, p = 0.0003; and Type I, p = 0.010), and had an earlier tumor onset compared to Type I (p = 0.012). K-ras mutations occurred in 21 of 50 (42%) of murine lung tumors sequenced. For both the nontransgenic and the SPC-TP53-273H transgenics, tumor K-ras codon 12-13 mutations occurred after 13 months with a peak incidence at 16-18 months. However, for the SPC-TP53-175H transgenics, K-ras codon 12-13 mutations were observed as early as 6 months, with a peak incidence between the ages of 10-12 months. Codons 12-13 transversion mutations were the predominant changes in the SPC-TP53-175H transgenics, whereas codon 61 transition mutations were more common in the SPC-TP53-273H transgenics. The observation of accelerated tumor onset, early appearance and high frequency of K-ras codon 12-13 mutations in the Type II TP53-175H mice suggests an enhanced oncogenic function of conformational TP53 mutations, and gains in early genetic instability for tumors containing these mutations compared to contact mutations.

Agents to treat BRAF-mutant lung cancer

BRAF mutations are seen in up to 3.5–4% of the non-small cell lung cancer (NSCLC) patients. BRAF V600E mutations account for 50% of these cases, and the remaining BRAF mutations are non-V600E. The biologic behavior of BRAF-mutated lung tumors tends to be more aggressive and resistant to chemotherapy, but responses to tyrosine kinase inhibitors such as BRAF inhibitors with or without MEK inhibitors have provided another effective tool to attain better response rates when compared to cytotoxic chemotherapy. New strategies such as immunotherapy are becoming as well another option to treat in the second-line setting patients with BRAF-mutated NSCLC.

First-Line Nivolumab Plus Ipilimumab in Advanced Non-Small-Cell Lung Cancer (CheckMate 568): Outcomes by Programmed Death Ligand 1 and Tumor Mutational Burden as Biomarkers

PURPOSE

CheckMate 568 is an open-label phase II trial that evaluated the efficacy and safety of nivolumab plus low-dose ipilimumab as first-line treatment of advanced/metastatic non–small-cell lung cancer (NSCLC). We assessed the association of efficacy with programmed death ligand 1 (PD-L1) expression and tumor mutational burden (TMB).

PATIENTS AND METHODS

Two hundred eighty-eight patients with previously untreated, recurrent stage IIIB/IV NSCLC received nivolumab 3 mg/kg every 2 weeks plus ipilimumab 1 mg/kg every 6 weeks. The primary end point was objective response rate (ORR) in patients with 1% or more and less than 1% tumor PD-L1 expression. Efficacy on the basis of TMB (FoundationOne CDx assay) was a secondary end point.

RESULTS

Of treated patients with tumor available for testing, 252 patients (88%) of 288 were evaluable for PD-L1 expression and 98 patients (82%) of 120 for TMB. ORR was 30% overall and 41% and 15% in patients with 1% or greater and less than 1% tumor PD-L1 expression, respectively. ORR increased with higher TMB, plateauing at 10 or more mutations/megabase (mut/Mb). Regardless of PD-L1 expression, ORRs were higher in patients with TMB of 10 or more mut/Mb (n = 48: PD-L1, ≥ 1%, 48%; PD-L1, < 1%, 47%) versus TMB of fewer than 10 mut/Mb (n = 50: PD-L1, ≥ 1%, 18%; PD-L1, < 1%, 5%), and progression-free survival was longer in patients with TMB of 10 or more mut/Mb versus TMB of fewer than 10 mut/Mb (median, 7.1 v 2.6 months). Grade 3 to 4 treatment-related adverse events occurred in 29% of patients.

CONCLUSION

Nivolumab plus low-dose ipilimumab was effective and tolerable as a first-line treatment of advanced/metastatic NSCLC. TMB of 10 or more mut/Mb was associated with improved response and prolonged progression-free survival in both tumor PD-L1 expression 1% or greater and less than 1% subgroups and was thus identified as a potentially relevant cutoff in the assessment of TMB as a biomarker for first-line nivolumab plus ipilimumab.

EGFR Genotyping of Matched Urine, Plasma, and Tumor Tissue in Patients With Non–Small-Cell Lung Cancer Treated With Rociletinib, an EGFR Tyrosine Kinase Inhibitor

Purpose

Liquid biopsies represent an attractive alternative to tissue biopsies, particularly rebiopsies, in determining patient eligibility for targeted therapies. Clinical utility of urine genotyping, however, has not been explored extensively. We evaluated epidermal growth factor receptor ( EGFR) T790M detection in matched urine, plasma, and tissue and the clinical outcomes of patients with advanced non–small-cell lung cancer treated with rociletinib.

Methods

Tissue (n = 540), plasma (n = 482), and urine (n = 213) were collected from evaluable patients enrolled in TIGER-X, a phase I/II study. Genotyping was performed by therascreen EGFR testing in tissue, BEAMing in plasma, and a quantitative short footprint assay (Trovera) in urine, which was used to further examine discordant samples.

Results

Positive percent agreement with tissue T790M results was similar for urine (82%; 142 of 173) and plasma (81%; 313 of 387) genotyping. Urine and plasma together identified more patients who were T790M positive (92%) than tissue alone (83%) among matched samples (n = 177). The ability to identify mutations in plasma was strongly associated with M stage ( P < .001); rate of T790M detection for patients with M1a/M0 disease increased from 54% for plasma alone to 85% when urine and plasma were both examined. Objective response rates of patients who were T790M positive were comparable between tumor (34%), plasma (32%), and urine (37%).

Conclusion

Clinical response to rociletinib was comparable irrespective of whether T790M status was identified by liquid or tissue biopsy. Combined, urine and plasma identified a higher percentage of patients who were T790M positive than tumor genotyping alone and improved detection of T790M, particularly in the absence of distant metastases. These findings support the noninvasive analysis of urine and plasma before tumor rebiopsy when assessing T790M status.

Identifying patterns of care for elderly patients with non-surgically treated stage III non-small cell lung cancer: an analysis of the national cancer database

Background

To compare patterns of care for elderly patients versus non-elderly patients with non-surgically treated stage III non-small cell lung cancer (NSCLC) using the National Cancer Database (NCDB). We hypothesize that elderly patients are less likely to receive curative treatments, including concurrent chemoradiation (CCRT), compared to non-elderly patients.

Methods

We identified patients from the NCDB between 2003 and 2014 with non-surgically treated stage III NSCLC. We defined elderly as ≥70 years old and non-elderly <70 years old. Treatment categories included: no treatment, palliative treatment (chemotherapy alone, radiation (RT) alone <59.4 Gy or chemoradiation (CRT) <59.4 Gy), or definitive treatment (RT alone ≥59.4 Gy or CRT ≥59.4 Gy). Differences in treatment between elderly and non-elderly were tested using the χ² test.

Results

We identified 57,602 elderly and 55,928 non-elderly patients. More elderly patients received no treatment (24.5% vs. 13.2%, P < 0.0001) and the elderly were less likely to receive definitive treatment (48.5% vs. 56.3%, P < 0.0001). CCRT was delivered in a significantly smaller proportion of elderly vs. non-elderly patients (66.0% vs. 78.9%, P < 0.0001 in patients treated with definitive intent; 32.0% vs. 44.5%, P < 0.0001 in patients receiving any treatment; and 24.2% vs. 38.6%, P < 0.0001 amongst all patients).

Conclusions

In this large study of patients with non-surgically treated stage III NSCLC, elderly patients were less likely to receive any treatment or treatment with definitive intent compared to the non-elderly. The lack of use of concurrent or sequential chemotherapy in the elderly with stage III NSCLC suggests that the optimal treatment approach for this vulnerable population remains undefined.

Electronic supplementary material

The online version of this article (10.1186/s13014-018-1142-7) contains supplementary material, which is available to authorized users.

Nivolumab plus Ipilimumab in Lung Cancer with a High Tumor Mutational Burden

BACKGROUND

Nivolumab plus ipilimumab showed promising efficacy for the treatment of non-small-cell lung cancer (NSCLC) in a phase 1 trial, and tumor mutational burden has emerged as a potential biomarker of benefit. In this part of an open-label, multipart, phase 3 trial, we examined progression-free survival with nivolumab plus ipilimumab versus chemotherapy among patients with a high tumor mutational burden (≥10 mutations per megabase).

METHODS

We enrolled patients with stage IV or recurrent NSCLC that was not previously treated with chemotherapy. Those with a level of tumor programmed death ligand 1 (PD-L1) expression of at least 1% were randomly assigned, in a 1:1:1 ratio, to receive nivolumab plus ipilimumab, nivolumab monotherapy, or chemotherapy; those with a tumor PD-L1 expression level of less than 1% were randomly assigned, in a 1:1:1 ratio, to receive nivolumab plus ipilimumab, nivolumab plus chemotherapy, or chemotherapy. Tumor mutational burden was determined by the FoundationOne CDx assay.

RESULTS

Progression-free survival among patients with a high tumor mutational burden was significantly longer with nivolumab plus ipilimumab than with chemotherapy. The 1-year progression-free survival rate was 42.6% with nivolumab plus ipilimumab versus 13.2% with chemotherapy, and the median progression-free survival was 7.2 months (95% confidence interval [CI], 5.5 to 13.2) versus 5.5 months (95% CI, 4.4 to 5.8) (hazard ratio for disease progression or death, 0.58; 97.5% CI, 0.41 to 0.81; P<0.001). The objective response rate was 45.3% with nivolumab plus ipilimumab and 26.9% with chemotherapy. The benefit of nivolumab plus ipilimumab over chemotherapy was broadly consistent within subgroups, including patients with a PD-L1 expression level of at least 1% and those with a level of less than 1%. The rate of grade 3 or 4 treatment-related adverse events was 31.2% with nivolumab plus ipilimumab and 36.1% with chemotherapy. ical; CheckMate 227 ClinicalTrials.gov number, NCT02477826 .).

CONCLUSIONS

Progression-free survival was significantly longer with first-line nivolumab plus ipilimumab than with chemotherapy among patients with NSCLC and a high tumor mutational burden, irrespective of PD-L1 expression level. The results validate the benefit of nivolumab plus ipilimumab in NSCLC and the role of tumor mutational burden as a biomarker for patient selection. (Funded by Bristol-Myers Squibb and Ono Pharmaceut

Expression Patterns, Prognostic Value, and Intratumoral Heterogeneity of PD-L1 and PD-1 in Thymoma and Thymic Carcinoma

INTRODUCTION

Thymic epithelial tumors (TETs) including thymoma and thymic carcinoma are rare tumors with little data available to guide treatment. Immunotherapy with checkpoint blockade has shown promising activity, but data regarding the expression patterns and prognostic implications of programmed death 1 (PD-1) and its ligand (PD-L1) in TETs have yielded conflicting results. Intratumoral heterogeneity of PD-1/L1 expression has been shown in other cancers, but has not been described in the TET literature.

METHODS

We performed a retrospective single-center review of 35 patients with resected TET. PD-1/L1 expression was assessed by immunohistochemistry using PD-1 clone: NAT105 and PD-L1 clone: 22C3. Tumor samples from 35 patients were evaluated including 32 patients with thymoma and 3 patients with thymic carcinoma.

RESULTS

PD-L1 expression was detected in 83% (29 of 35) tumor samples, including 100% (3 of 3) of thymic carcinoma patients and 81% (26 of 32) of thymoma patients. PD-1 expression was detected in 77% (27 of 35), including 33% (1 of 3) of thymic carcinoma patients and 81% (26 of 32) thymoma patients. High PD-1 expression was associated with lower grade tumors. Unlike prior studies, PD-L1 expression was not associated with higher grade tumors or higher stage. Neither PD-L1 nor PD-1 expression was significantly associated with survival. Three patients with thymoma had multiple tumor sections evaluated for expression of PD-1/L1, with differing expression patterns of both PD-L1 and PD-1 observed in two patients.

CONCLUSIONS

This study confirms high expression of PD-L1 and PD-1 in TET and shows for the first time intratumoral heterogeneity of PD-L1 and PD-1 in thymoma patients.

Lung cancer exosomes as drivers of epithelial mesenchymal transition

Exosomes, a subgroup of extracellular vesicles (EVs), have been shown to serve as a conduit for the exchange of genetic information between cells. Exosomes are released from all types of cells but in abundance from cancer cells. The contents of exosomes consist of proteins and genetic material (mRNA, DNA and miRNA) from the cell of origin. In this study, we examined the effects of exosomes derived from human lung cancer serum and both highly metastatic and non-metastatic cells on recipient human bronchial epithelial cells (HBECs). We found that exosomes derived from highly metastatic lung cancer cells and human late stage lung cancer serum induced vimentin expression, and epithelial to mesenchymal transition (EMT) in HBECs. Exosomes derived from highly metastatic cancer cells as well as late stage lung cancer serum induce migration, invasion and proliferation in non-cancerous recipient cells. Our results suggest that cancer derived exosomes could be a potential mediator of EMT in the recipient cells.

The Addition of Chemotherapy to Radiation Therapy Improves Survival in Elderly Patients with Stage III Non-Small Cell Lung Cancer

INTRODUCTION

Elderly patients account for the majority of lung cancer diagnoses but are poorly represented in clinical trials. We evaluated the overall survival (OS) of elderly patients with stage III NSCLC treated with definitive radiation compared with that of patients treated with definitive chemoradiation.

METHODS

We conducted a comparative effectiveness study of radiation therapy versus chemoradiation in elderly (≥70 years old) patients with stage III NSCLC not treated surgically diagnosed from 2003 to 2014; the patients were identified by using the National Cancer Database. Two cohorts were evaluated: patients (n = 5023) treated with definitive radiation (≥59.4 Gy) and patients (n = 18,206) treated with definitive chemoradiation. Chemoradiation was further defined as concurrent (radiation and chemotherapy started within 30 days of each other) or sequential (radiation started >30 days after chemotherapy). We compared OS between the treatment groups by using the Kaplan-Meier method and Cox proportional hazards regression before and after propensity score matching (PSM).

RESULTS

Treatment with chemoradiation was associated with improved OS versus that with radiation both before PSM (hazard ratio [HR] = 0.66, 95% confidence interval [CI]: 0.64-0.68, p < 0.001) and after PSM (HR = 0.67, 95% CI: 0.64-0.70, p < 0.001). Relative to concurrent chemoradiation, sequential chemoradiation was associated with a 9% reduction in the risk for death (HR = 0.91, 95% CI: 0.85-0.96, p = 0.002).

CONCLUSIONS

We found that definitive chemoradiation resulted in a survival advantage compared with definitive radiation in elderly patients. Sequential chemotherapy and radiation was superior to concurrent chemoradiation. Although prospective trials are needed, this analysis suggests that chemoradiation should be strongly considered for elderly patients and the optimal sequencing of chemotherapy and radiation remains an unanswered question for this patient population.

The Impact of Smoking and TP53 Mutations in Lung Adenocarcinoma Patients with Targetable Mutations-The Lung Cancer Mutation Consortium (LCMC2)

Purpose: Multiplex genomic profiling is standard of care for patients with advanced lung adenocarcinomas. The Lung Cancer Mutation Consortium (LCMC) is a multi-institutional effort to identify and treat oncogenic driver events in patients with lung adenocarcinomas.Experimental Design: Sixteen U.S. institutions enrolled 1,367 patients with lung cancer in LCMC2; 904 were deemed eligible and had at least one of 14 cancer-related genes profiled using validated methods including genotyping, massively parallel sequencing, and IHC.Results: The use of targeted therapies in patients with EGFR, ERBB2, or BRAF p.V600E mutations, ALK, ROS1, or RET rearrangements, or MET amplification was associated with a survival increment of 1.5 years compared with those with such mutations not receiving targeted therapy, and 1.0 year compared with those lacking a targetable driver. Importantly, 60 patients with a history of smoking derived similar survival benefit from targeted therapy for alterations in EGFR/ALK/ROS1, when compared with 75 never smokers with the same alterations. In addition, coexisting TP53 mutations were associated with shorter survival among patients with EGFR, ALK, or ROS1 alterations.Conclusion: Patients with adenocarcinoma of the lung and an oncogenic driver mutation treated with effective targeted therapy have a longer survival, regardless of prior smoking history. Molecular testing should be performed on all individuals with lung adenocarcinomas irrespective of clinical characteristics. Routine use of massively parallel sequencing enables detection of both targetable driver alterations and tumor suppressor gene and other alterations that have potential significance for therapy selection and as predictive markers for the efficacy of treatment. Clin Cancer Res; 24(5); 1038-47. ©2017 AACR.

Epigenetic Therapeutics and Their Impact in Immunotherapy of Lung Cancer

Lung cancer is the leading cause of cancer-related death in the United States and worldwide. Novel therapeutic developments are critically necessary to improve outcomes for this disease. Aberrant epigenetic change plays an important role in lung cancer development and progression. Therefore, drugs targeting the epigenome are being investigated in the treatment of lung cancer. Monotherapy of epigenetic therapeutics such as DNA methyltransferase inhibitors (DNMTi) and histone deacetylase inhibitors (HDACi) have so far not shown any apparent benefit while one of the clinical trials with the combinations of DNMTi and HDACi showed a small positive signal for treating lung cancer. Combinations of DNMTi and HDACi with chemotherapies have some efficacy but are often limited by increased toxicities. Preclinical data and clinical trial results suggest that combining epigenetic therapeutics with targeted therapies might potentially improve outcomes in lung cancer patients. Furthermore, several clinical studies suggest that the HDACi vorinostat could be used as a radiosensitizer in lung cancer patients receiving radiation therapy. Immune checkpoint blockade therapies are revolutionizing lung cancer management. However, only a minority of lung cancer patients experience long-lasting benefits from immunotherapy. The role of epigenetic reprogramming in boosting the effects of immunotherapy is an area of active investigation. Preclinical studies and early clinical trial results support this approach which may improve lung cancer treatment, with potentially prolonged survival and tolerable toxicity. In this review, we discuss the current status of epigenetic therapeutics and their combination with other antineoplastic therapies, including novel immunotherapies, in lung cancer management.

Radiation Dose to the Thoracic Vertebral Bodies Is Associated With Acute Hematologic Toxicities in Patients Receiving Concurrent Chemoradiation for Lung Cancer: Results of a Single-Center Retrospective Analysis

PURPOSE

To test the hypothesis that increasing radiation therapy (RT) dose to the thoracic vertebral bodies (TVBs) contributes to the development of hematologic toxicities (HTs) in patients with lung cancer.

METHODS AND MATERIALS

Cases of non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) treated with definitive chemoradiation with concurrent platinum-based doublet chemotherapy at our institution from 2007 to 2016 were identified. Mean TVB dose and the volume of TVBs receiving at least 5 to 60 Gy (V₅-V₆₀) were retrospectively recorded. Logistic regression was used to test associations between grade ≥3 HT (HT3+) and dosimetric/clinical parameters. Normal tissue complication probability was evaluated using the Lyman-Kutcher-Burman (LKB) model for HT3+, and receiver operating characteristics analysis was used to determine dosimetric cut-points.

RESULTS

We identified 201 patients, the majority having NSCLC (n=162, 81%) and stage III to IV disease (n=179, 89%). All patients received either cisplatin/etoposide (n=107, 53%) or carboplatin/paclitaxel (n=94, 47%). Median RT dose was 60 Gy (range, 60-70 Gy). The rate of HT3+ was 49% (n=99). Increasing mean TVB dose (per Gy) was associated with higher odds of developing HT3+ (odds ratio 1.041, 95% confidence interval 1.004-1.080, P=.032), as were increasing TVB V₅ to V₂₀. These dosimetric correlates to HT3+ persisted on multivariate analysis. Constrained optimization of the LKB model for HT3+ yielded the parameters: n=1, m=1.79, and TD₅₀=21.4 Gy. Optimal cut-points identified were V₅=65%, V₁₀=60%, V₂₀=50%, and mean dose=23.5 Gy. Patients with values above these cut-points had an approximately 2-fold increased risk of HT3+.

CONCLUSIONS

We found that mean TVB dose and low-dose parameters (V₅-V₂₀) were associated with HT3+ in chemoradiation for lung cancer. Per the LKB model, bone marrow behaves like a parallel organ (n=1), implying that mean TVB dose is a useful predictor for toxicity. These data suggest that efforts to spare dose to the TVBs may reduce rates of severe HT.

NCCN Guidelines Insights: Malignant Pleural Mesothelioma, Version 3.2016

These NCCN Guidelines Insights focus on recent updates to the NCCN Guidelines for Malignant Pleural Mesothelioma (MPM). These NCCN Guidelines Insights discuss systemic therapy regimens and surgical controversies for MPM. The NCCN panel recommends cisplatin/pemetrexed (category 1) for patients with MPM. The NCCN panel also now recommends bevacizumab/cisplatin/pemetrexed as a first-line therapy option for patients with unresectable MPM who are candidates for bevacizumab. The complete version of the NCCN Guidelines for MPM, available at NCCN.org, addresses all aspects of management for MPM including diagnosis, evaluation, staging, treatment, surveillance, and therapy for recurrence and metastasis; NCCN Guidelines are intended to assist with clinical decision-making.

Analytic validation and real-time clinical application of an amplicon-based targeted gene panel for advanced cancer

Multiplex somatic testing has emerged as a strategy to test patients with advanced cancer. We demonstrate our analytic validation approach for a gene hotspot panel and real-time prospective clinical application for any cancer type. The TruSight Tumor 26 assay amplifies 85 somatic hotspot regions across 26 genes. Using cell line and tumor mixes, we observed that 100% of the 14,715 targeted bases had at least 1000x raw coverage. We determined the sensitivity (100%, 95% CI: 96-100%), positive predictive value (100%, 95% CI: 96-100%), reproducibility (100% concordance), and limit of detection (3% variant allele frequency at 1000x read depth) of this assay to detect single nucleotide variants and small insertions and deletions. Next, we applied the assay prospectively in a clinical tumor sequencing study to evaluate 174 patients with metastatic or advanced cancer, including frozen tumors, formalin-fixed tumors, and enriched peripheral blood mononuclear cells in hematologic cancers. We reported one or more somatic mutations in 89 (53%) of the sequenced tumors (167 passing quality filters). Forty-three of these patients (26%) had mutations that would enable eligibility for targeted therapies. This study demonstrates the validity and feasibility of applying TruSight Tumor 26 for pan-cancer testing using multiple specimen types.

Non-Small Cell Lung Cancer, Version 5.2017, NCCN Clinical Practice Guidelines in Oncology

This selection from the NCCN Guidelines for Non-Small Cell Lung Cancer (NSCLC) focuses on targeted therapies and immunotherapies for metastatic NSCLC, because therapeutic recommendations are rapidly changing for metastatic disease. For example, new recommendations were added for atezolizumab, ceritinib, osimertinib, and pembrolizumab for the 2017 updates.

NCCN Guidelines Insights: Non-Small Cell Lung Cancer, Version 4.2016

These NCCN Guidelines Insights focus on recent updates in the 2016 NCCN Guidelines for Non-Small Cell Lung Cancer (NSCLC; Versions 1-4). These NCCN Guidelines Insights will discuss new immunotherapeutic agents, such as nivolumab and pembrolizumab, for patients with metastatic NSCLC. For the 2016 update, the NCCN panel recommends immune checkpoint inhibitors as preferred agents (in the absence of contraindications) for second-line and beyond (subsequent) therapy in patients with metastatic NSCLC (both squamous and nonsquamous histologies). Nivolumab and pembrolizumab are preferred based on improved overall survival rates, higher response rates, longer duration of response, and fewer adverse events when compared with docetaxel therapy.

A Randomized Phase II Study of Linsitinib (OSI-906) Versus Topotecan in Patients With Relapsed Small-Cell Lung Cancer

LESSONS LEARNED

Targeted therapy options for SCLC patients are limited; no agent, thus far, has resulted in a strategy promising enough to progress to phase III trials.Linsitinib, a potent insulin growth factor-1-receptor tyrosine kinase inhibitor, may be one agent with activity against SCLC.Despite lack of a reliable predictive biomarker in this disease, which may have partly contributed to the negative outcome reported here, linsitinib, although safe, showed no clinical activity in unselected, relapsed SCLC patients.

BACKGROUND

Treatment of relapsed small-cell lung cancer (SCLC) remains suboptimal. Insulin growth factor-1 receptor (IGF-1R) signaling plays a role in growth, survival, and chemoresistance in SCLC. Linsitinib is a potent IGF-1R tyrosine kinase inhibitor that potentially may be active against SCLC.

METHODS

In this phase II study, 8 eligible patients were randomly assigned in a 1:2 ratio to topotecan (1.5 mg/m² intravenously or 2.3 mg/m² orally, daily for 5 days for 4 cycles) or linsitinib (150 mg orally twice daily until progression). The primary endpoint was progression-free survival. Patients with relapsed SCLC, platinum sensitive or resistant, performance status (PS) 0-2, and adequate hematologic, renal, and hepatic function were enrolled. Patients with diabetes, cirrhosis, and those taking insulinotropic agents were excluded. Crossover to linsitinib was allowed at progression.

RESULTS

Fifteen patients received topotecan (8 resistant, 3 with PS 2) and 29 received linsitinib (16 resistant, 5 with PS 2). Two partial responses were observed with topotecan. Only 4 of 15 patients with topotecan and 1 of 29 with linsitinib achieved stable disease. Median progression-free survival was 3.0 (95% confidence interval [CI], 1.5-3.6) and 1.2 (95% CI, 1.1-1.4) months for topotecan and linsitinib, respectively (p = .0001). Median survival was 5.3 (95% CI, 2.2-7.6) and 3.4 (95% CI, 1.8-5.6) months for topotecan and linsitinib, respectively (p = .71). Grade 3/4 adverse events (>5% incidence) included anemia, thrombocytopenia, neutropenia/leukopenia, diarrhea, fatigue, dehydration, and hypokalemia for topotecan; and thrombocytopenia, fatigue, and alanine aminotransferase/aspartate aminotransferase elevations for linsitinib.

CONCLUSION

Linsitinib was safe but showed no clinical activity in unselected, relapsed SCLC patients.

Phase I Results from a Study of Crizotinib in Combination with Erlotinib in Patients with Advanced Nonsquamous Non-Small Cell Lung Cancer

INTRODUCTION

This phase I trial was conducted to determine the safety, maximum tolerated dose (MTD)/recommended phase II dose, and efficacy of crizotinib plus erlotinib in patients with advanced NSCLC.

METHODS

Patients with NSCLC and an Eastern Cooperative Oncology Group performance status of 0 to 2 after failure of one or two prior chemotherapy regimens were eligible. Erlotinib, 100 mg, was given continuously once daily starting between day -14 and -7; crizotinib, 200 mg twice daily (dose level 1) or 150 mg twice daily (dose level -1), was added continuously beginning on day 1 of treatment cycle 1. Potential pharmacokinetic interactions between crizotinib and erlotinib were evaluated.

RESULTS

Twenty-seven patients received treatment; 26 received crizotinib plus erlotinib. Frequent adverse events were diarrhea, rash, decreased appetite, and fatigue. Dose-limiting toxicities were dehydration, diarrhea, dry eye, dysphagia, dyspepsia, esophagitis and vomiting. The MTD was crizotinib, 150 mg twice daily, with erlotinib, 100 mg once daily. Crizotinib increased the erlotinib area under the concentration-time curve 1.5-fold (dose level -1) and 1.8-fold (dose level 1). The plasma level of crizotinib appeared to be unaffected by coadministration of erlotinib. Two patients whose tumors harbored activating EGFR mutations achieved confirmed partial responses, one at each crizotinib dose level.

CONCLUSIONS

The MTD of the combination of crizotinib and erlotinib in patients with advanced NSCLC was crizotinib, 150 mg twice daily, with erlotinib, 100 mg once daily, which is less than the approved dose of either agent. The phase II portion of the study was not initiated.

A Phase I Trial to Evaluate Antibody-Dependent Cellular Cytotoxicity of Cetuximab and Lenalidomide in Advanced Colorectal and Head and Neck Cancer

mAbs can induce antibody-dependent cellular cytotoxicity (ADCC) via the innate immune system's ability to recognize mAb-coated cancer cells and activate immune effector cells. Lenalidomide is an immunomodulatory agent with the capacity to stimulate immune cell cytokine production and ADCC activity. This phase I trial evaluated the combination of cetuximab with lenalidomide for the treatment of advanced colorectal and head and neck squamous cell cancers (HNSCC). This trial included patients with advanced colorectal cancer or HNSCC. Treatment consisted of cetuximab 500 mg/m(2) i.v. every two weeks with lenalidomide given orally days 1-21 on a 28-day cycle. Three dose levels of lenalidomide were evaluated (15, 20, 25 mg). Correlative studies included measurement of ADCC, FcγRIIIA polymorphism genotyping, measurement of serum cytokine levels, and flow cytometric analysis of immune cell subtypes. Twenty-two patients were enrolled (19 colorectal cancer, 3 HNSCC). Fatigue was the only dose-limiting toxicity. One partial response was observed and 8 patients had stable disease at least 12 weeks. The recommended phase II dose is cetuximab 500 mg/m(2) with lenalidomide 25 mg daily, days 1-21. Correlative studies demonstrated a dose-dependent increase in natural killer cytotoxic activity with increasing doses of lenalidomide. Cetuximab and lenalidomide were well tolerated. There was a lenalidomide dose-dependent increase in ADCC with higher activity in patients enrolled in cohort 3 than those enrolled in cohorts 1/2. Although response was not a primary endpoint, there was evidence of antitumor activity for the combination therapy. Further investigation of lenalidomide as an immunomodulator in solid tumors is warranted. Mol Cancer Ther; 15(9); 2244-50. ©2016 AACR.

Abstract 4438: Promoter hypermethylation status of Fanconi Anemia (FA) pathway genes FANCF, FANCL and FANCS in non-small cell lung cancer (NSCLC)

Gene promoter methylation is an epigenetic mechanism used by cells to control gene expression. Over recent decades, scientists have made various discoveries linking DNA methylation to several adverse outcomes, including human cancers. The Fanconi Anemia (FA) pathway is involved in homologous recombination, one of the major mechanisms of DNA repair. This pathway is essential for human cells to maintain integrity following DNA damage. Cancers with defective FA pathways are expected to be more sensitive to cross-link based therapy, or to treatments in which additional repair mechanisms are targeted. The FA pathway contains at least 19 genes, and some of the members have been implicated in susceptibility to a number of cancers by genetic or epigenetic alterations. Promoter methylation in FA genes is thought to play a role in the occurrence of cancer.

Recently we screened 139 non-small cell lung cancer (NSCLC) formalin-fixed, paraffin-embedded (FFPE) tumors for FANCD2 foci formation by FA triple stain immunofluorescence (FATSI) analysis. Among the 104 evaluable tumors, 23 (22%) were FANCD2 foci negative. Since epigenetic inactivation can be one of the mechanisms for FA functional deficiency in these tumors, we evaluated 39 NSCLC samples (21 foci positive and 18 foci negative; 21 adenocarcinomas, 17 squamous cell carcinomas, 1 large cell carcinoma) for FANCF, FANCL and FANCS (BRCA1) promoter methylation.

Human lung tumor tissue samples were obtained from The Tissue Procurement Shared Resources of the Ohio State University after IRB approval. Genomic DNA and total RNA samples were isolated from frozen lung tumor and matching non-tumor tissues. The promoter methylation status of FANCF, FANCL and FANCS was evaluated using methylation-specific PCR (MS-PCR).

Among the 18 FATSI negative tumors, promoter methylation was found in FANCF (1 adenocarcinoma), FANCL (1 adenocarcinoma) and FANCS (1 adenocarcinoma). Among the 21 FATSI positive tumors, no promoter methylation was detected in FANCF or FANCL. Promoter methylation in FANCS was found in 1 (squamous cell carcinoma) of 21 FATSI positive tumors.

The above observations suggest that epigenetic alterations, specifically methylation, can be one of the factors that contribute to FA functional deficiency in NSCLC patients. These findings may have clinical implications, since these tumors may be more sensitive to cross-link based therapy. However, an important caveat is that these changes may not be stable and could revert during treatment. Further studies in FA gene expression are needed to determine the impact of FA gene promoter methylation on FA repair foci formation.

Citation Format: Andrew Fink, Arjun Kalvala, Li Gao, Kathleen Dotts, Brittany Aguila, Shirley Tang, Gregory A. Otterson, Miguel A. Villalona-Calero, Wenrui Duan. Promoter hypermethylation status of Fanconi Anemia (FA) pathway genes FANCF, FANCL and FANCS in non-small cell lung cancer (NSCLC). [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4438.

Rad51C-ATXN7 fusion gene expression in colorectal tumors

Background

Fusion proteins have unique oncogenic properties and their identification can be useful either as diagnostic or therapeutic targets. Next generation sequencing data have previously shown a fusion gene formed between Rad51C and ATXN7 genes in the MCF7 breast cancer cell line. However, the existence of this fusion gene in colorectal patient tumor tissues is largely still unknown.

Methods

We evaluated for the presence of Rad51C-ATXN7 fusion gene in colorectal tumors and cells by RT-PCR, PCR, Topo TA cloning, Real time PCR, immunoprecipitation and immunoblotting techniques.

Results

We identified two forms of fusion mRNAs between Rad51C and ATXN7 in the colorectal tumors, including a Variant 1 (fusion transcript between Rad51C exons 1–7 and ATXN7 exons 6–13), and a Variant 2 (between Rad51C exons 1–6 and ATXN7 exons 6–13). In silico analysis showed that the Variant 1 produces a truncated protein, whereas the Variant 2 was predicted to produce a fusion protein with molecular weight of 110 KDa. Immunoprecipitation and Western blot analysis further showed a 110 KDa protein in colorectal tumors. 5-Azacytidine treatment of LS-174 T cells caused a 3.51-fold increase in expression of the fusion gene (Variant 2) as compared to no treatment controls evaluated by real time PCR.

Conclusion

In conclusion we found a fusion gene between DNA repair gene Rad51C and neuro-cerebral ataxia Ataxin-7 gene in colorectal tumors. The in-frame fusion transcript of Variant 2 results in a fusion protein with molecular weight of 110 KDa. In addition, we found that expression of fusion gene is associated with functional impairment of Fanconi Anemia (FA) DNA repair pathway in colorectal tumors. The expression of Rad51C-ATXN7 in tumors warrants further investigation, as it suggests the potential of the fusion gene in treatment and predictive value in colorectal cancers.

Electronic supplementary material

The online version of this article (doi:10.1186/s12943-016-0527-1) contains supplementary material, which is available to authorized users.