IKKα inactivation promotes Kras-initiated lung adenocarcinoma development through disrupting major redox regulatory pathways.

Lung adenocarcinoma (ADC) and squamous cell carcinoma (SCC) are two distinct and predominant types of human lung cancer. IκB kinase α (IKKα) has been shown to suppress lung SCC development, but its role in ADC is unknown. We found inactivating mutations and homologous or hemizygous deletions in the CHUK locus, which encodes IKKα, in human lung ADCs. The CHUK deletions significantly reduced the survival time of patients with lung ADCs harboring KRAS mutations. In mice, lung-specific Ikkα ablation (IkkαΔLu ) induces spontaneous ADCs and promotes KrasG12D-initiated ADC development, accompanied by increased cell proliferation, decreased cell senescence, and reactive oxygen species (ROS) accumulation. IKKα deletion up-regulates NOX2 and down-regulates NRF2, leading to ROS accumulation and blockade of cell senescence induction, which together accelerate ADC development. Pharmacologic inhibition of NADPH oxidase or ROS impairs KrasG12D-mediated ADC development in IkkαΔLu mice. Therefore, IKKα modulates lung ADC development by controlling redox regulatory pathways. This study demonstrates that IKKα functions as a suppressor of lung ADC in human and mice through a unique mechanism that regulates tumor cell-associated ROS metabolism

Global expression analysis of cancer/testis genes in uterine cancers reveals a high incidence of BORIS expression

Abstract Purpose: Cancer/testis (CT) genes predominantly expressed in the testis (germ cells) and generally not in other normal tissues are aberrantly expressed in human cancers. This highly restricted expression provides a unique opportunity to use these CTgenes for diagnostics, immunotherapeutic, or other targeted therapies. The purpose of this study was to identify those CT genes with the greatest incidence of expression in uterine cancers. Experimental Design: We queried the expression of known and putative CT gene transcripts (representing 79 gene loci) using whole genome gene expression arrays. Specifically, the global gene expressions of uterine cancers (n = 122) and normal uteri (n = 10) were determined using expression data from the Affymetrix HG-U133A and HG-U133B chips. Additionally, we also examined the brother of the regulator of imprinted sites (BORIS) transcript by reverse transcription-PCR and quantitative PCR because its transcript was not represented on the array. Results: Global microarray analysis detected many CT genes expressed in various uterine cancers; however, no individual CT gene was expressed in more than 25% of all cancers. The expression of the two most commonly expressed CT genes on the arrays, MAGEA9 (24 of 122 cancers and 0 of10 normal tissues) and Down syndrome critical region 8 (DSCR8)/MMA1 (16 if 122 cancers and 0 of 10 normal tissues), was confirmed by reverse transcription-PCR methods, validating the array screening approach. In contrast to the relatively low incidence of expression of the other CTgenes, BORIS expression was detected in 73 of 95 (77%) endometrial cancers and 24 of 31 (77%) uterine mixed mesodermal tumors. Conclusions: These data provide the first extensive survey of multiple CT genes in uterine cancers. Importantly, we detected a high frequency of BORIS expression in uterine cancers, suggesting its potential as an immunologic or diagnostic target for these cancers. Given the high incidence of BORIS expression and its possible regulatory role, an examination of BORIS function in the etiology of these cancers is warranted

The GYMSSA trial: a prospective randomized trial comparing gastrectomy, metastasectomy plus systemic therapy versus systemic therapy alone

<p>Abstract</p> <p>Background</p> <p>The standard of care for metastatic gastric cancer (MGC) is systemic chemotherapy which leads to a median survival of 6-15 months. Survival beyond 3 years is rare. For selected groups of patients with limited MGC, retrospective studies have shown improved overall survival following gastrectomy and metastasectomies including peritoneal stripping with continuous hyperthermic peritoneal perfusion (CHPP), liver resection, and pulmonary resection. Median survival after liver resection for MGC is up to 34 months, with a five year survival rate of 24.5%. Similarly, reported median survival after pulmonary resection of MGC is 21 months with long term survival of greater than 5 years a possibility. Several case reports and small studies have documented evidence of long-term survival in select individuals who undergo CHPP for MGC.</p> <p>Design</p> <p>The GYMSSA trial is a prospective randomized trial for patients with MGC. It is designed to compare two therapeutic approaches: gastrectomy with metastasectomy plus systemic chemotherapy (GYMS) versus systemic chemotherapy alone (SA). Systemic therapy will be composed of the FOLFOXIRI regimen. The aim of the study is to evaluate overall survival and potential selection criteria to determine those patients who may benefit from surgery plus systemic therapy. The study will be conducted by the Surgery Branch at the National Cancer Institute (NCI), National Institutes of Health (NIH) in Bethesda, Maryland. Surgeries and followup will be done at the NCI, and chemotherapy will be given by either the local oncologist or the medical oncology branch at NCI.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov ID. NCT00941655</p

Gene expression profiling of alveolar soft-part sarcoma (ASPS)

<p>Abstract</p> <p>Background</p> <p>Alveolar soft-part sarcoma (ASPS) is an extremely rare, highly vascular soft tissue sarcoma affecting predominantly adolescents and young adults. In an attempt to gain insight into the pathobiology of this enigmatic tumor, we performed the first genome-wide gene expression profiling study.</p> <p>Methods</p> <p>For seven patients with confirmed primary or metastatic ASPS, RNA samples were isolated immediately following surgery, reverse transcribed to cDNA and each sample hybridized to duplicate high-density human U133 plus 2.0 microarrays. Array data was then analyzed relative to arrays hybridized to universal RNA to generate an unbiased transcriptome. Subsequent gene ontology analysis was used to identify transcripts with therapeutic or diagnostic potential. A subset of the most interesting genes was then validated using quantitative RT-PCR and immunohistochemistry.</p> <p>Results</p> <p>Analysis of patient array data versus universal RNA identified elevated expression of transcripts related to angiogenesis (ANGPTL2, HIF-1 alpha, MDK, c-MET, VEGF, TIMP-2), cell proliferation (PRL, IGFBP1, NTSR2, PCSK1), metastasis (ADAM9, ECM1, POSTN) and steroid biosynthesis (CYP17A1 and STS). A number of muscle-restricted transcripts (ITGB1BP3/MIBP, MYF5, MYF6 and TRIM63) were also identified, strengthening the case for a muscle cell progenitor as the origin of disease. Transcript differentials were validated using real-time PCR and subsequent immunohistochemical analysis confirmed protein expression for several of the most interesting changes (MDK, c-MET, VEGF, POSTN, CYP17A1, ITGB1BP3/MIBP and TRIM63).</p> <p>Conclusion</p> <p>Results from this first comprehensive study of ASPS gene expression identifies several targets involved in angiogenesis, metastasis and myogenic differentiation. These efforts represent the first step towards defining the cellular origin, pathogenesis and effective treatment strategies for this atypical malignancy.</p

Targeting the epigenome for the treatment and prevention of lung cancer

Alterations in chromatin structure resulting from aberrant DNA methylation and perturbations of the histone code profoundly influence gene expression during pulmonary carcinogenesis. Recent studies indicate that DNA demethylating agents and histone deacetylase (HDAC) inhibitors synergistically induce gene expression and apoptosis in cultured lung cancer cells, and prevent lung cancer development in animals following exposure to tobacco carcinogens. Preliminary clinical trials have established proof of principle regarding the use of DNA demethylating agents and HDAC inhibitors for enhancing immunogenicity and apoptosis of lung cancer cells, and have revealed the complexities concerning the mechanisms by which chromatin remodeling agents mediate antitumor effects in vivo. These data support additional investigations pertaining to the epigenetics of lung cancer, and the evaluation of chromatin remodeling agents for the treatment and prevention of this disease

Growth factor receptors as targets for lung cancer therapy

Dysregulated signal transduction of growth factor receptors contributes to the process of malignant transformation by promoting cell proliferation, motility, and invasion through extracellular matrix as well as angiogenesis. Epidermal growth factor receptors (EGFR), and to a lesser extent HER2/neu, is overexpressed in the majority of nonsmall cell lung cancer (NSCLC) compared with normal tissue, making them ideal targets for the development of novel therapeutics for this disease. Multiple clinical trials have demonstrated that antireceptor strategies employing antagonistic monoclonal antibodies or low molecular weight tyrosine kinase inhibitors against EGFR are well tolerated and occasionally result in objective clinical responses in patients with advanced NSCLC. This report provides an overview of the molecular basis and the preclinical evidence supporting clinical development of anti-EGFR therapy as well as results of phase I–III clinical trials of these compounds in treating patients with solid tumors including NSCLC

Enhancement of depsipeptide-mediated apoptosis of lung or esophageal cancer cells by flavopiridol: activation of the mitochondria-dependent death-signaling pathway

Treating cancer cells with depsipeptide, a novel antitumor agent currently in a phase II clinical trial, causes potent upregulation of p21/WAF1 expression and cell arrest at G1 and G2 checkpoints. p21/WAF1 upregulation, however, impedes the ability of depsipeptide to induce significant apoptosis. This study was designed to determine whether flavopiridol, a synthetic cyclin-dependent kinase inhibitor known to inhibit p21 expression in tumor cells, could enhance depsipeptide-mediated apoptosis in cultured lung and esophageal cancer cells. Lung or esophageal cancer cells were exposed to depsipeptide, flavopiridol, or a combination of depsipeptide and flavopiridol. Cytotoxicity and apoptosis were quantitated by means of (4,5-dimethylthiazo-2-yl)-2,5-diphenyl tetrazolium bromide and terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling-based assays, respectively. Cytosolic cytochrome c levels, caspase 9 activity, mitochondrial membrane depolarization, and dependence of apoptosis on caspase 9 in treated cells were studied to determine the role of the mitochondria in mediating apoptosis induced by this drug combination. Flavopiridol completely abolished depsipeptide-mediated dose-dependent upregulation of p21/WAF1 expression. Combining flavopiridol with depsipeptide resulted in a 3- to 8-fold reduction of depsipeptide inhibitory concentration of 50% values that was closely paralleled by synergistic enhancement of apoptosis (4- to 10-fold higher than levels of cell death induced by either drug alone) in all cancer cell lines. The essential role of mitochondria in mediating cell death was indicated by robust translocation of cytochrome c from the mitochondria into the cytosol, 2.5- to 5-fold activation of caspase 9, severe disruption of mitochondrial inner membrane potential, and complete inhibition of apoptosis by the selective caspase 9 inhibitor. More important, this drug combination was not toxic to primary normal epithelial cells derived from the airway or skin. The depsipeptide plus flavopiridol combination exhibits powerful and selective cytocidal activity against cancer but not normal cells. Apoptosis induced by this combination is mediated by the mitochondria-dependent death pathway