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Inactivation of p53 is present in almost every tumor, and hence, p53-reactivation strategies are an important aspect of cancer therapy. Common mechanisms for p53 loss in cancer include expression of p53-negative regulators such as MDM2, which mediate the degradation of wildtype p53 (p53α), and inactivating mutations in the TP53 gene. Currently, approaches to overcome p53 deficiency in these cancers are limited. Here, using non–small cell lung cancer and glioblastoma multiforme cell line models, we show that two alternatively spliced, functional truncated isoforms of p53 (p53β and p53γ, comprising exons 1 to 9β or 9γ, respectively) and that lack the C-terminal MDM2-binding domain have markedly reduced susceptibility to MDM2-mediated degradation but are highly susceptible to nonsense-mediated decay (NMD), a regulator of aberrant mRNA stability. In cancer cells harboring MDM2 overexpression or TP53 mutations downstream of exon 9, NMD inhibition markedly upregulates p53β and p53γ and restores activation of the p53 pathway. Consistent with p53 pathway activation, NMD inhibition induces tumor suppressive activities such as apoptosis, reduced cell viability, and enhanced tumor radiosensitivity, in a relatively p53-dependent manner. In addition, NMD inhibition also inhibits tumor growth in a MDM2-overexpressing xenograft tumor model. These results identify NMD inhibition as a novel therapeutic strategy for restoration of p53 function in p53-deficient tumors bearing MDM2 overexpression or p53 mutations downstream of exon 9, subgroups that comprise approximately 6% of all cancers.

Background: SARS-CoV-2 infection is the cause of the respiratory illness COVID-19, which presents most frequently with respiratory symptoms SARS-CoV-2 cell entry requires interactions with ACE2 and TMPRSS2 on the surface of the host cell Cancer patients and, specifically, those with thoracic malignancies seem to experience poorer clinical outcomes Methods: We utilized bulk and single-cell transcriptional data from a combination of normal and malignant tissues and cells from aerodigestive and respiratory tracts to explore mechanisms governing the expression of ACE2 and TMPRSS2 Additionally, we determined the effect of EMT induction, ZEB1 modulation, and SARS-CoV-2 infection on ACE2 expression Results: Our bulk data suggests that aerodigestive and lung cancer models express a broad range of ACE2 and TMRPSS2, particularly in epithelial cells, and would serve as good models for studying SARS-CoV-2 infection We assessed the relationship between ACE2 and epithelial differentiation in numerous datasets, and found consistent positive correlations with transcriptional and microRNA signifiers of epithelial differentiation The miR-200 family – zinc finger E-box-binding homeobox 1 (ZEB1) pathway, which is an established regulator of EMT, also directly regulates ACE2 expression, likely via putative ZEB1 repressor sites located in the ACE2 promoter Furthermore, SARS-CoV-2 infection reduces ACE2 expression and shifts cells to a more mesenchymal phenotype with loss of EPCAM and upregulation of ZEB1 and other EMT-associated genes Conclusions: ACE2-positive cells are almost exclusively epithelial and unexpectedly rare, considering the devastating impact of this infection Following viral entry, SARS-CoV-2 infection induces molecular changes within the cells that are reminiscent of EMT, including increased ZEB1 ZEB1, in turn, appears to directly repress the expression of ACE2 This SARS-CoV-2-induced ACE2 deficiency, compounded by the downregulation of genes, including claudins, which play a critical role in restricting epithelial and endothelial permeability, exposes respiratory cells to increased risk of edema and acute respiratory distress syndrome (ARDS) Legal entity responsible for the study: The authors Funding: NIH/NCI R01-CA207295 (L A B ), NIH/NCI U01-CA213273 (L A B , J V H ), CCSG P30-CA01667 (L A B ), University of Texas SPORE in Lung Cancer P5-CA070907 (L A B , D L G , J V H , C M G ), the Department of Defense (LC170171;L A B ), Khalifa Bin Zayed Al Nahyan Foundation (C M G ), RP170067 (EMP), through generous philanthropic contributions to The University of Texas MD Anderson Lung Cancer Moon Shot Program and Andrew Sabin Family Fellowship, and The Rexanna Foundation for Fighting Lung Cancer Disclosure: C Gay: Research grant/Funding (self): Astra Zeneca J V Heymach: Advisory/Consultancy: AstraZeneca;Advisory/Consultancy: Boehringer Ingelheim;Advisory/Consultancy: Exelixis;Advisory/Consultancy: Genentech;Advisory/Consultancy: GlaxoSmithKline;Advisory/Consultancy: Guardant Health;Advisory/Consultancy: Hengrui;Advisory/Consultancy: Spectrum L A Byers: Advisory/Consultancy, Research grant/Funding (self): AstraZeneca;Advisory/Consultancy, Research grant/Funding (self): AbbVie;Advisory/Consultancy, Research grant/Funding (self): GenMab;Advisory/Consultancy: BergenBio;Advisory/Consultancy: Pharma Mar SA;Advisory/Consultancy, Research grant/Funding (self): Sierra Oncology;Advisory/Consultancy: Merck;Advisory/Consultancy: Bristol Myers Squibb;Advisory/Consultancy: Genentech;Advisory/Consultancy: Pfizer;Research grant/Funding (self): Tolero Pharmaceuticals All other authors have declared no conflicts of interest

Purpose: In locoregionally advanced, resectable cutaneous squamous cell carcinoma of the head and neck (CSCC-HN), surgery followed by radiotherapy is standard but can be cosmetically and functionally devastating, and many patients will have recurrence. Patients and Methods: Newly diagnosed or recurrent stage III–IVA CSCC-HN patients amenable to curative-intent surgery received two cycles of neoadjuvant PD-1 inhibition. The primary endpoint was ORR per RECIST 1.1. Secondary endpoints included pathologic response [pathologic complete response (pCR) or major pathologic response (MPR; ≤10% viable tumor)], safety, DSS, DFS, and OS. Exploratory endpoints included immune biomarkers of response. Results: Of 20 patients enrolled, 7 had recurrent disease. While only 6 patients [30%; 95% confidence interval (CI), 11.9–54.3] had partial responses by RECIST, 15 patients (75%; 95% CI, 50.9–91.3) had a pCR (n = 11) or MPR (n = 4). No SAEs ocurred during or after the neoadjuvant treatment. At a median follow-up of 22.6 months (95% CI, 21.7–26.1), one patient progressed and died, one died without disease, and two developed recurrence. The 12-month DSS, DFS, and OS rates were 95% (95% CI, 85.9–100), 89.5% (95% CI, 76.7–100), and 95% (95% CI, 85.9–100), respectively. Gene expression studies revealed an inflamed tumor microenvironment in patients with pCR or MPR, and CyTOF analyses demonstrated a memory CD8+ T-cell cluster enriched in patients with pCR. Conclusions: Neoadjuvant immunotherapy in locoregionally advanced, resectable CSCC-HN is safe and induces a high pathologic response rate. Pathologic responses were associated with an inflamed tumor microenvironment.

Mouse models are powerful tools to study lung cancer initiation and progression in vivo and have contributed significantly to recent advances in therapy. Using micro-computed tomography to monitor and study parenchymal and extra-parenchymal metastases in existing murine models of lung cancer is challenging owing to a lack of radiographic contrast and difficulty in achieving respiratory gating. To facilitate the analysis of these in vivo imaging studies and study of tumor progression in murine models we developed a novel, rapid, semi-automated method of calculating thoracic tumor burden from computed tomography images. This method, in which commercially available software is used to calculate the mass of the thoracic cavity (MTC), takes into account the aggregate tumor burden in the thoracic cavity. The present study showed that in tumor-free mice, the MTC does not change over time and is not affected by breathing, whereas in tumor-bearing mice, the increase in the MTC is a measure of tumor mass that correlates well with tumor burden measured by lung weight. Tumor burden calculated with our MTC method correlated with that measured by lung weight as well as or better than that calculated using four established methods. To test this method, we assessed metastatic tumor development and response to a pharmacologic PLK1 inhibitor in an orthotopic xenograft mouse model. PLK1 inhibition significantly inhibited tumor growth. Our results demonstrate that the MTC method can be used to study dynamic changes in tumor growth and response to therapeutics in genetically engineered mouse models and orthotopic xenograft mouse models of lung cancer.

Common mechanisms for p53 loss in cancer include expression of MDM2 or the human papilloma virus (HPV)-encoded E6 protein which both mediate degradation of wild-type (WT) p53 (p53α). Here, we show that two alternatively-spliced, functional, truncated isoforms of p53 (p53β and p53γ, containing exons 1-9 of the p53 gene) can be markedly upregulated by pharmacologic or genetic inhibition of nonsense mediated decay (NMD), a regulator of aberrant mRNA stability. These isoforms lack the MDM2 binding domain and hence have reduced susceptibility to MDM2-mediated degradation. In MDM2-overexpressing cells bearing wildtypeTP53gene, NMD blockade increased p53β/γ expression and p53 pathway activation, enhanced radiosensitivity, and inhibited tumor growth. A similar pattern was observed in HPV+cancer cells and in cancer cells with p53 mutations downstream of exon 9. These results identify a novel therapeutic strategy for restoration of p53 function in tumors rendered p53 deficient through MDM2 overexpression, HPV infection, or certain p53 mutations.

Purpose/Objective Radiation-induced lymphopenia has been associated with poor survival outcomes in certain solid tumors such as esophageal, lung, cervical and pancreatic cancers. We aim to determine the effect of treatment-related lymphopenia during radiotherapy on outcomes of patients with oropharyngeal cancer. Materials/Methods A retrospective analysis of all patients who completed definitive radiotherapy for oropharyngeal cancer at The University of Texas MD Anderson Cancer Center and had blood counts taken during radiotherapy from 2002 to 2013 were included. Patient, tumor and treatment characteristics, clinical outcomes and lymphocyte counts during radiotherapy were recorded. Lymphopenia was graded according to the CTCAE v4.0. Survival rates were estimated using the Kaplan-Meier method and compared with log-rank tests. Results 850 patients were evaluated. The median age was 57 years. The majority of the cohort had p16/HPV-positive disease (71%), 8% had HPV-negative disease and 21% were unknown. The median radiation total dose was 70 Gy. 45% of patients had induction chemotherapy, and 87% had concurrent chemotherapy. 703 (83%) patients developed ≥grade 3 (G3) lymphopenia and 209 (25%) had grade 4 (G4) lymphopenia during radiotherapy. The median follow-up was 59 months; the 5-year overall survival rate was 81%. There were no significant differences in overall survival rates nor in disease control rates, in those who developed G3/G4 lymphopenia compared with those who did not. No significant effect of lymphopenia on survival was observed when analyzed according to p16/HPV status. Conclusion In this large cohort of patients with oropharyngeal cancer, the development of lymphopenia during radiotherapy did not impact outcomes.

// Nene N. Kalu 1, 6 , Tuhina Mazumdar 1 , Shaohua Peng 1 , Li Shen 2 , Vaishnavi Sambandam 1 , Xiayu Rao 2 , Yuanxin Xi 2 , Lerong Li 2 , Yuan Qi 2 , Frederico O. Gleber-Netto 3 , Ameeta Patel 3 , Jing Wang 2, 4 , Mitchell J. Frederick 5 , Jeffrey N. Myers 3, 4 , Curtis R. Pickering 3, 4 and Faye M. Johnson 1, 4 1 Department of Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA 2 Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA 3 Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA 4 The University of Texas Graduate School of Biomedical Sciences, Houston, Texas, USA 5 Department of Otolaryngology, Baylor College of Medicine, Houston, Texas, USA 6 Current/Present address: Lonza Viral Therapy, Houston, Texas, USA Correspondence to: Faye M. Johnson, email: fmjohns@mdanderson.org Keywords: human papillomavirus, cervical cancer, head and neck squamous cell carcinoma, cell lines, mutation Received: June 22, 2017 Accepted: August 21, 2017 Published: September 21, 2017 ABSTRACT Human cancer cell lines are the most frequently used preclinical models in the study of cancer biology and the development of therapeutics. Although anatomically diverse, human papillomavirus (HPV)-driven cancers have a common etiology and similar mutations that overlap with but are distinct from those found in HPV-negative cancers. Building on prior studies that have characterized subsets of head and neck squamous cell carcinoma (HNSCC) and cervical squamous cell carcinoma (CESC) cell lines separately, we performed genomic, viral gene expression, and viral integration analyses on 74 cell lines that include all readily-available HPV-positive (9 HNSCC, 8 CESC) and CESC (8 HPV-positive, 2 HPV-negative) cell lines and 55 HPV-negative HNSCC cell lines. We used over 700 human tumors for comparison. Mutation patterns in the cell lines were similar to those of human tumors. We confirmed HPV viral protein and mRNA expression in the HPV-positive cell lines. We found HPV types in three CESC cell lines that are distinct from those previously reported. We found that cell lines and tumors had similar patterns of viral gene expression; there were few sites of recurrent HPV integration. As seen in tumors, HPV integration did appear to alter host gene expression in cell lines. The HPV-positive cell lines had higher levels of p16 and lower levels of Rb protein expression than did the HPV-negative lines. Although the number of HPV-positive cell lines is limited, our results suggest that these cell lines represent suitable models for studying HNSCC and CESC, both of which are common and lethal.

Background The survival advantage of induction chemotherapy (IC) followed by locoregional treatment is controversial in locally advanced head and neck squamous cell carcinoma (LAHNSCC). We previously showed feasibility and safety of cetuximab-based IC (paclitaxel/carboplatin/cetuximab—PCC, and docetaxel/cisplatin/5-fluorouracil/cetuximab—C-TPF) followed by local therapy in LAHNSCC. The primary end point of this phase II clinical trial with randomization to PCC and C-TPF followed by combined local therapy in patients with LAHNSCC stratified by human papillomavirus (HPV) status and T-stage was 2-year progression-free survival (PFS) compared with historical control. Patients and methods Eligible patients were ≥18 years with squamous cell carcinoma of the oropharynx, oral cavity, nasopharynx, hypopharynx, or larynx with measurable stage IV (T0–4N2b–2c/3M0) and known HPV by p16 status. Stratification was by HPV and T-stage into one of the two risk groups: (i) low-risk: HPV-positive and T0–3 or HPV-negative and T0–2; (ii) intermediate/high-risk: HPV-positive and T4 or HPV-negative and T3–4. Patient reported outcomes were carried out. Results A total of 136 patients were randomized in the study, 68 to each arm. With a median follow up of 3.2 years, the 2-year PFS in the PCC arm was 89% in the overall, 96% in the low-risk and 67% in the intermediate/high-risk groups; in the C-TPF arm 2-year PFS was 88% in the overall, 88% in the low-risk and 89% in the intermediate/high-risk groups. Conclusion The observed 2-year PFS of PCC in the low-risk group and of C-TPF in the intermediate/high-risk group showed a 20% improvement compared with the historical control derived from RTOG-0129, therefore reaching the primary end point of the trial.

Purpose: Head and neck squamous cell carcinoma (HNSCC) is driven largely by the loss of tumor suppressor genes, including NOTCH1, but lacks a biomarker-driven targeted therapy. Although the PI3K/mTOR pathway is frequently altered in HNSCC, the disease has modest clinical response rates to PI3K/mTOR inhibitors and lacks validated biomarkers of response. We tested the hypothesis that an unbiased pharmacogenomics approach to PI3K/mTOR pathway inhibitors would identify novel, clinically relevant molecular vulnerabilities in HNSCC with loss of tumor suppressor function. Experimental Design: We assessed the degree to which responses to PI3K/mTOR inhibitors are associated with gene mutations in 59 HNSCC cell lines. Apoptosis in drug-sensitive cell lines was confirmed in vitro and in vivo. NOTCH1 pathway components and PDK1 were manipulated with drugs, gene editing, knockdown, and overexpression. Results: PI3K/mTOR inhibition caused apoptosis and decreased colony numbers in HNSCC cell lines harboring NOTCH1 loss-of-function mutations (NOTCH1MUT) and reduced tumor size in subcutaneous and orthotopic xenograft models. In all cell lines, NOTCH1MUT was strongly associated with sensitivity to six PI3K/mTOR inhibitors. NOTCH1 inhibition or knockout increased NOTCH1WT HNSCC sensitivity to PI3K/mTOR inhibition. PDK1 levels dropped following PI3K/mTOR inhibition in NOTCH1MUT but not NOTCH1WT HNSCC, and PDK1 overexpression rescued apoptosis in NOTCH1MUT cells. PDK1 and AKT inhibitors together caused apoptosis in NOTCH1WT HNSCC but had little effect as single agents. Conclusions: Our findings suggest that NOTCH1MUT predicts response to PI3K/mTOR inhibitors, which may lead to the first biomarker-driven targeted therapy for HNSCC, and that targeting PDK1 sensitizes NOTCH1WT HNSCC to PI3K/mTOR pathway inhibitors.

Importance In recurrent human papilloma virus (HPV)–driven cancer, immune checkpoint blockade with anti–programmed cell death 1 (PD-1) antibodies produces tumor regression in only a minority of patients. Therapeutic HPV vaccines have produced strong immune responses to HPV-16, but vaccination alone has been ineffective for invasive cancer. Objective To determine whether the efficacy of nivolumab, an anti–PD-1 immune checkpoint antibody, is amplified through treatment with ISA 101, a synthetic long-peptide HPV-16 vaccine inducing HPV-specific T cells, in patients with incurable HPV-16–positive cancer. Design, Setting, and Participants In this single-arm, single-center phase 2 clinical trial, 24 patients with incurable HPV-16–positive cancer were enrolled from December 23, 2015, to December 12, 2016. Duration of follow-up for censored patients was 12.2 months through August 31, 2017. Interventions The vaccine ISA101, 100 μg/peptide, was given subcutaneously on days 1, 22, and 50. Nivolumab, 3 mg/kg, was given intravenously every 2 weeks beginning day 8 for up to 1 year. Main Outcomes and Measures Assessment of efficacy reflected in the overall response rate (per Response Evaluation Criteria in Solid Tumors, version 1.1). Results Of the 24 patients (4 women and 20 men; 22 with oropharyngeal cancer; median age, 60 years [range, 36-73 years]), the overall response rate was 33% (8 patients; 90% CI, 19%-50%). Median duration of response was 10.3 months (95% CI, 10.3 months to inestimable). Five of 8 patients remain in response. Median progression-free survival was 2.7 months (95% CI, 2.5-9.4 months). Median overall survival was 17.5 months (95% CI, 17.5 months to inestimable). Grades 3 to 4 toxicity occurred in 2 patients (asymptomatic grade 3 transaminase level elevation in 1 patient and grade 4 lipase elevation in 1 patient), requiring discontinuation of nivolumab therapy. Conclusions and Relevance The overall response rate of 33% and median overall survival of 17.5 months is promising compared with PD-1 inhibition alone in similar patients. A randomized clinical trial to confirm the contribution of HPV-16 vaccination to tumoricidal effects of PD-1 inhibition is warranted for further study. Trial Registration ClinicalTrials.gov identifier:NCT02426892

Incidence of HPV(+) oropharyngeal squamous cell carcinoma (OPSCC) has been increasing dramatically. Although long-term survival rates for these patients are high, they often suffer from permanent radiotherapy-related morbidity. This has prompted the development of de-escalation clinical protocols to reduce morbidity. However, a subset of patients do not respond even to standard therapy and have poor outcomes. It is unclear how to properly identify and treat the high- and low-risk HPV(+) OPSCC patients. Since HPV positivity drives radiotherapy sensitivity, we hypothesized that variations in HPV biology may cause differences in treatment response and outcome. By analyzing gene expression data, we identified variations in HPV-related molecules among HPV(+) OPSCC. A subset of tumors presented a molecular profile distinct from that of typical HPV(+) tumors and exhibited poor treatment response, indicating molecular and clinical similarities with HPV(–) tumors. These molecular changes were also observed in vitro and correlated with radiation sensitivity. Finally, we developed a prognostic biomarker signature for identification of this subgroup of HPV(+) OPSCC and validated it in independent cohorts of oropharyngeal and cervical carcinomas. These findings could translate to improved patient stratification for treatment deintensification and new therapeutic approaches for treatment-resistant HPV-related cancer.

Improved therapies are greatly needed for non-small cell lung cancer (NSCLC) that does not harbor targetable kinase mutations or translocations. We previously demonstrated that NSCLC cells that harbor kinase-inactivating BRAF mutations (KIBRAF) undergo senescence when treated with the multitargeted kinase inhibitor dasatinib. Similarly, treatment with dasatinib resulted in a profound and durable response in a patient with KIBRAF NSCLC. However, no canonical pathways explain dasatinib-induced senescence in KIBRAF NSCLC. To investigate the underlying mechanism, we used 2 approaches: gene expression and reverse phase protein arrays. Both approaches showed that DNA repair pathways were differentially modulated between KIBRAF NSCLC cells and those with wild-type (WT) BRAF. Consistent with these findings, dasatinib induced DNA damage and activated DNA repair pathways leading to senescence only in the KIBRAF cells. Moreover, dasatinib-induced senescence was dependent on Chk1 and p21, proteins known to mediate DNA damage-induced senescence. Dasatinib also led to a marked decrease in TAZ but not YAP protein levels. Overexpression of TAZ inhibited dasatinib-induced senescence. To investigate other vulnerabilities in KIBRAF NSCLC cells, we compared the sensitivity of these cells with that of WTBRAF NSCLC cells to 79 drugs and identified a pattern of sensitivity to EGFR and MEK inhibitors in the KIBRAF cells. Clinically approved EGFR and MEK inhibitors, which are better tolerated than dasatinib, could be used to treat KIBRAF NSCLC. Our novel finding that dasatinib induced DNA damage and subsequently activated DNA repair pathways leading to senescence in KIBRAF NSCLC cells represents a unique vulnerability with potential clinical applications.

PURPOSE: To determine the maximum tolerated dose (MTD) of BEZ235, an oral inhibitor of class I PI3K and mTOR complexes 1 and 2. METHODS: We performed a phase I/Ib, multicenter, open-label study of oral BEZ235 administered in a continuous daily schedule. The study consisted of two parts: dose-escalation part and safety-expansion part. BEZ235 was administered as a single agent to patients with solid tumors or in combination with trastuzumab for HER2+ advanced breast cancer (aBC). Primary end points were MTD, safety, and tolerability. The secondary end point was pharmacokinetics. Other formulations of BEZ235, solid dispersion system (SDS) sachet, and SDS capsules were also assessed. RESULTS: One hundred and eighty-three patients were enrolled; single-agent BEZ235 was administered as hard gelatin capsule (n = 59), SDS capsules A and B (n = 33), and SDS sachet (n = 61), amongst which SDS sachet was chosen as the preferred formulation. The monotherapy MTD for capsule A and SDS sachet was determined to be 1000 and 1200 mg/day, respectively. Thirty patients with HER2+ aBC received BEZ235 in combination with trastuzumab. The MTD of BEZ235 in combination with trastuzumab was 600 mg/day. A total of four patients (13.3%) achieved partial response across the different groups. Most frequent AEs in single agent and combination cohorts included nausea (80.3 and 93.3%), diarrhea (75.4 and 80.0%), and vomiting (63.9 and 63.3%). CONCLUSIONS: The MTD of BEZ235 as single agent was 1200 and 600 mg/day with trastuzumab. Pharmacokinetic profiles showed low-to-moderate variability at low dose (10 mg) and high variability at high doses (100 mg and above). Gastrointestinal AEs were frequent at high doses.

The genomic alterations identified in head and neck squamous cell carcinoma (HNSCC) tumors have not resulted in any changes in clinical care, making the development of biomarker-driven targeted therapy for HNSCC a major translational gap in knowledge. To fill this gap, we used 59 molecularly characterized HNSCC cell lines and found that mutations of AJUBA, SMAD4 and RAS predicted sensitivity and resistance to treatment with inhibitors of polo-like kinase 1 (PLK1), checkpoint kinases 1 and 2, and WEE1. Inhibition or knockdown of PLK1 led to cell-cycle arrest at the G2/M transition and apoptosis in sensitive cell lines and decreased tumor growth in an orthotopic AJUBA-mutant HNSCC mouse model. AJUBA protein expression was undetectable in most AJUBA-mutant HNSCC cell lines, and total PLK1 and Bora protein expression were decreased. Exogenous expression of wild-type AJUBA in an AJUBA-mutant cell line partially rescued the phenotype of PLK1 inhibitor-induced apoptosis and decreased PLK1 substrate inhibition, suggesting a threshold effect in which higher drug doses are required to affect PLK1 substrate inhibition. PLK1 inhibition was an effective therapy for HNSCC in vitro and in vivo. However, biomarkers to guide such therapy are lacking. We identified AJUBA, SMAD4 and RAS mutations as potential candidate biomarkers of response of HNSCC to treatment with these mitotic inhibitors.

Favorable outcomes for human papillomavirus-associated oropharyngeal cancer have led to interest in identifying a subgroup of patients with the lowest risk of disease recurrence after therapy. De-intensification of therapy for this group may result in survival outcomes that are similar to those associated with current therapy but with less toxicity. To advance this effort, this study analyzed the outcomes of oropharyngeal cancer patients treated with or without systemic therapy.This was a retrospective study of patients with oropharyngeal cancer treated between 1985 and 2012. The criteria for inclusion were ≤10 pack-years of cigarette smoking and stage III/IVA cancer limited to T1-3, N1-N2b, and T3N0 disease. A survival analysis was performed with the primary endpoint of progression-free survival (PFS).The cohort included 857 patients. Systemic therapy was given to 439 patients (51%). The median survival was 80 months. The 2-year PFS rate was 91%. When the analysis was limited to 324 patients irradiated without systemic therapy, the 2- and 5-year PFS rates were 90% and 85%, respectively. Furthermore, for these 324 patients, the 5-year PFS rates for T1, T2, and T3 disease were 90%, 83%, and 70%, respectively. The 5-year PFS rate for patients treated with systemic therapy for T3 disease was 77% (P = .07).According to the low-risk definition currently established in cooperative trials, the patients had a 2-year PFS rate approximating 90%. When patients who were treated with radiation alone were evaluated, no compromise was observed in this high rate of PFS, which is higher than the 2-year PFS thresholds used in current cooperative trials. Cancer 2016;122:1702-7. © 2016 American Cancer Society.

Molecular annotated patient-derived xenograft (PDX) models are useful for the preclinical investigation of anticancer drugs and individualized anticancer therapy. We established 23 PDXs from 88 surgical specimens of lung cancer patients and determined gene mutations in these PDXs and their paired primary tumors by ultradeep exome sequencing on 202 cancer-related genes. The numbers of primary tumors with deleterious mutations in TP53, KRAS, PI3KCA, ALK, STK11, and EGFR were 43.5%, 21.7%, 17.4%, 17.4%, 13.0%, and 8.7%, respectively. Other genes with deleterious mutations in ≥3 (13.0%) primary tumors were MLL3, SETD2, ATM, ARID1A, CRIPAK, HGF, BAI3, EP300, KDR, PDGRRA and RUNX1. Of 315 mutations detected in the primary tumors, 293 (93%) were also detected in their corresponding PDXs, indicating that PDXs have the capacity to recapitulate the mutations in primary tumors. Nevertheless, a substantial number of mutations had higher allele frequencies in the PDXs than in the primary tumors, or were not detectable in the primary tumor, suggesting the possibility of tumor cell enrichment in PDXs or heterogeneity in the primary tumors. The molecularly annotated PDXs generated from this study could be useful for future translational studies.

The Eph family of receptors is the largest family of receptor tyrosine kinases, but it remains poorly studied in lung cancer. We aimed to systematically explore the human Eph receptors and their ligands, the ephrins, in lung adenocarcinoma. The prognostic impact of Eph receptor and ephrin gene expression was analyzed using 2 independent cohorts of lung adenocarcinoma. Gene expression profiles in lung adenocarcinoma compared with normal adjacent lung were studied in 3 independent cohorts and in cell lines. Gene expression profiles were validated with quantitative polymerase chain reaction (qPCR) and Western blotting in cell lines. Functional studies to assess the role of Eph receptor A4 (EphA4) were carried out in vitro. The biological effects of EphA4 in lung cancer cell lines were assayed following overexpression and knockdown. Of the 11 Eph receptors and 8 ephrins analyzed, only EphA4 and ephrin A1 gene expression were consistently associated with an improved outcome in patients with lung adenocarcinoma. Expression levels of EphA4 by microarray correlated well with expression levels measured by qPCR and Western blotting. EphA4 overexpression reduced cell migration and invasion but did not affect cell cycle, apoptosis, or drug sensitivity. Surprisingly, EphA4 was expressed at higher levels in cancer compared with non-cancer tissues and cell lines. EphA4 gene expression is associated with an improved outcome in patients with resected lung adenocarcinoma, possibly by affecting cancer cell migration and invasion. Mol Cancer Ther; 11(9); 2021–32. ©2012 AACR.

Recent studies have established that amplification of the MET proto-oncogene can cause resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in non-small cell lung cancer (NSCLC) cell lines with EGFR-activating mutations. The role of non-amplified MET in EGFR-dependent signaling before TKI resistance, however, is not well understood. Using NSCLC cell lines and transgenic models, we demonstrate here that EGFR activation by either mutation or ligand binding increases MET gene expression and protein levels. Our analysis of 202 NSCLC patient specimens was consistent with these observations: levels of MET were significantly higher in NSCLC with EGFR mutations than in NSCLC with wild-type EGFR. EGFR regulation of MET levels in cell lines occurred through the hypoxia-inducible factor (HIF)-1alpha pathway in a hypoxia-independent manner. This regulation was lost, however, after MET gene amplification or overexpression of a constitutively active form of HIF-1alpha. EGFR- and hypoxia-induced invasiveness of NSCLC cells, but not cell survival, were found to be MET dependent. These findings establish that, absent MET amplification, EGFR signaling can regulate MET levels through HIF-1alpha and that MET is a key downstream mediator of EGFR-induced invasiveness in EGFR-dependent NSCLC cells.

The first Meeting on “Molecular Origins of Lung Cancer - Prospects for Personalized Prevention and Therapy” was held from January 10 to 14, 2010 in San Diego, California. The purpose of the meeting was to discuss important basic, translational, and clinical work aimed at improving lung cancer prevention, detection, and treatment. Topics included drug design, target identification, early detection, cancer stem cells, microRNAs, genome wide approaches to determining risk and outcome, mouse models, and tumor microenvironment. The role of cancer advocates in supporting research was an important component of the meeting. Meeting presentations demonstrated that emerging technologies can molecularly dissect lung cancers that have important relevance for clinical utility. This includes molecular based strategies not only for treatment of established cancers but also individualized and molecularly-based strategies for cancer risk reduction and chemoprevention.