Wnt and Hedgehog Are Critical Mediators of Cigarette Smoke-Induced Lung Cancer

BACKGROUND: Lung cancer is the leading cause of cancer death in the world, and greater than 90% of lung cancers are cigarette smoke-related. Current treatment options are inadequate, because the molecular basis of cigarette-induced lung cancer is poorly understood. METHODOLOGY/PRINCIPAL FINDINGS: Here, we show that human primary or immortalized bronchial epithelial cells exposed to cigarette smoke for eight days in culture rapidly proliferate, show anchorage-independent growth, and form tumors in nude mice. Using this model of the early stages of smoke-induced tumorigenesis, we examined the molecular changes leading to lung cancer. We observed that the embryonic signaling pathways mediated by Hedgehog and Wnt are activated by smoke. Pharmacological inhibition of these pathways blocked the transformed phenotype. CONCLUSIONS/SIGNIFICANCE: These experiments provide a model in which the early stages of smoke-induced tumorigenesis can be elicited, and should permit us to identify molecular changes driving this process. Results obtained so far indicate that smoke-induced lung tumors are driven by activation of two embryonic regulatory pathways, Hedgehog (Hh) and Wnt. Based on the current and emerging availability of drugs to inhibit Hh and Wnt signaling, it is possible that an understanding of the role of Hh and Wnt in lung cancer pathogenesis will lead to the development of new therapies

Development of novel monoclonal antibodies and immunoassays for sensitive and specific detection of SULF1 endosulfatase

BackgroundCell-surface heparan sulfate proteoglycans (HSPGs) function as receptors or co-receptors for ligand binding and mediate the transmission of critical extracellular signals into cells. The complex and dynamic modifications of heparan sulfates on the core proteins are highly regulated to achieve precise signaling transduction. Extracellular endosulfatase Sulf1 catalyzes the removal of 6-O sulfation from HSPGs and thus regulates signaling mediated by 6-O sulfation on HSPGs. The expression of Sulf1 is altered in many cancers. Further studies are needed to clarify Sulf1 role in tumorigenesis, and new tools that can expand our knowledge in this field are required.MethodsWe have developed and validated novel SULF1 monoclonal antibodies (mAbs). The isotype and subclass for each of these antibodies were determined. These antibodies provide invaluable reagents to assess SULF1- tissue and blood levels by immunohistochemistry and ELISA assays, respectively.ResultsThis study reports novel mAbs and immunoassays developed for sensitive and specific human Sulf1 protein detection. Using these SULF1 mAbs, we developed an ELISA assay to investigate whether blood-derived SULF1 may be a useful biomarker for detecting cancer early. Furthermore, we have demonstrated the utility of these antibodies for Sulf1 protein detection, localization, and quantification in biospecimens using various immunoassays.ConclusionsThis study describes novel Sulf1 mAbs suitable for various immunoassays, including Western blot analysis, ELISA, and immunohistochemistry, which can help understand Sulf1 pathophysiological role.General significanceNew tools to assess and clarify SULF1 role in tumorigenesis are needed. Our novel Sulf1 mAbs and immunoassays assay may have utility for such application

SULF2 expression by immunohistochemistry and overall survival in oesophageal cancer: a cohort study.

OBJECTIVES: Oesophageal cancer is the eighth most commonly diagnosed cancer worldwide, and there is a need for biomarkers to improve diagnosis, prognosis and treatment. Sulfatases 2 (SULF2) is an extracellular endosulphatase that regulates several signalling pathways in carcinogenesis and has been associated with poor prognosis. This study evaluates the relationship between SULF2 expression by immunohistochemistry and overall survival in patients with oesophageal cancer. DESIGN: Cohort study. SETTING: Single tertiary care centre. PARTICIPANTS: We included patients who underwent esophagectomy for invasive oesophageal adenocarcinoma and squamous cell carcinoma at a tertiary care centre from 1997 to 2006. We excluded patients with recurrent oesophageal cancer or less than 3 mm invasive tumour on H&E stained slide. A section from each paraffin-embedded tissue specimen was stained with an anti-SULF2 monoclonal antibody. OUTCOME MEASURES: A pathologist blinded to overall survival determined the percentage and intensity of tumour cells staining. Vital status was obtained through the Social Security Death Master File, and overall survival was calculated from the date of surgery. RESULTS: One-hundred patients with invasive oesophageal cancer were identified, including 75 patients with adenocarcinoma and 25 patients with squamous cell carcinoma. The squamous cell carcinoma samples had a higher mean percentage and intensity of tumour cells staining compared with the adenocarcinoma samples. After adjusting for age, sex, race, histological type, stage and neoadjuvant therapy, for every 10% increase in percentage of tumour cells staining for SULF2, the HR for death increased by 13% (95% CI 1.01 to 1.25; p=0.03). CONCLUSIONS: The majority of adenocarcinoma samples and all of the squamous cell carcinoma samples had SULF2 staining. The percentage of tumour cells staining for SULF2 was significantly associated with overall survival. Thus, SULF2 is a potential biomarker in oesophageal cancer and may have an important role in the management of patients with this disease

TACE/ADAM-17 phosphorylation by PKC-epsilon mediates premalignant changes in tobacco smoke-exposed lung cells.

Tobacco smoke predisposes humans and animals to develop lung tumors, but the molecular events responsible for this are poorly understood. We recently showed that signaling mechanisms triggered by smoke in lung cells could lead to the activation of a growth factor signaling pathway, thereby promoting hyperproliferation of lung epithelial cells. Hyperproliferation is considered a premalignant change in the lung, in that increased rates of DNA synthesis are associated with an increased number of DNA copying errors, events that are exacerbated in the presence of tobacco smoke carcinogens. Despite the existence of DNA repair mechanisms, a small percentage of these errors go unrepaired and can lead to tumorigenic mutations. The results of our previous study showed that an early event following smoke exposure was the generation of oxygen radicals through the activation of NADPH oxidase. Although it was clear that these radicals transduced signals through the epidermal growth factor receptor (EGFR), and that this was mediated by TACE-dependent cleavage of amphiregulin, it remained uncertain how oxygen radicals were able to activate TACE.In the present study, we demonstrate for the first time that phosphorylation of TACE at serine/threonine residues by tobacco smoke induces amphiregulin release and EGFR activation. TACE phosphorylation is triggered in smoke-exposed lung cells by the ROS-induced activation of PKC through the action of SRC kinase. Furthermore, we identified PKCε as the PKC isoform involved in smoke-induced TACE activation and hyperproliferation of lung cells.Our data elucidate new signaling paradigms by which tobacco smoke promotes TACE activation and hyperproliferation of lung cells

AMXI-5001, a novel dual parp1/2 and microtubule polymerization inhibitor for the treatment of human cancers.

Poly (ADP-ribose) polymerase (PARP) has recently emerged as a central mediator in cancer resistance against numerous anticancer agents to include chemotherapeutic agents such as microtubule targeting agents and DNA damaging agents. Here, we describe AMXI-5001, a novel, highly potent dual PARP1/2 and microtubule polymerization inhibitor with favorable metabolic stability, oral bioavailability, and pharmacokinetic properties. The potency and selectivity of AMXI-5001 were determined by biochemical assays. Anticancer activity either as a single-agent or in combination with other antitumor agents was evaluated in vitro. In vivo antitumor activity as a single-agent was assessed in a triple-negative breast cancer (TNBC) model. AMXI-5001 demonstrates comparable IC50 inhibition against PARP and microtubule polymerization as clinical PARP inhibitors (Olaparib, Rucaparib, Niraparib, and Talazoparib) and the potent polymerization inhibitor (Vinblastine), respectively. In vitro, AMXI-5001 exhibited selective antitumor cytotoxicity across a wide variety of human cancer cells with much lower IC50s than existing clinical PARP1/2 inhibitors. AMXI-5001 is highly active in both BRCA mutated and wild type cancers. AMXI-5001 is orally bioavailable. AMXI-5001 elicited a remarkable In vivo preclinical anti-tumor activity in a BRCA mutated TNBC model. Oral administration of AMXI-5001 induced complete regression of established tumors, including exceedingly large tumors. AMXI-5001 resulted in superior anti-tumor effects compared to either single agent (PARP or microtubule) inhibitor or combination with both agents. AMXI-5001 will enter clinical trial testing soon and represents a promising, novel first in class dual PARP1/2 and microtubule polymerization inhibitor that delivers continuous and synchronous one-two punch cancer therapy with one molecule

Chapter Nine Glycosylation Alterations in Lung and Brain Cancer

Alterations in glycosylation are common in cancer and are thought to contribute to disease. Lung cancer and primary malignant brain cancer, most commonly glioblastoma, are genetically heterogeneous diseases with extremely poor prognoses. In this review, we summarize the data demonstrating that glycosylation is altered in lung and brain cancer. We then use specific examples to highlight the diverse roles of glycosylation in these two deadly diseases and illustrate shared mechanisms of oncogenesis. In addition to alterations in glycoconjugate biosynthesis, we also discuss mechanisms of postsynthetic glycan modification in cancer. We suggest that alterations in glycosylation in lung and brain cancer provide novel tumor biomarkers and therapeutic targets

Novel dual action PARP and microtubule polymerization inhibitor AMXI-5001 powerfully inhibits growth of esophageal carcinoma both alone and in combination with radiotherapy.

Esophageal cancer is one of the leading causes of cancer deaths globally with an incidence that is concentrated in specific hot spots in Eastern Asia, the Middle East, Eastern Africa, and South America. 10-year overall survival for patients treated with standard of care chemoradiation followed by surgical resection is below 40% highlighting the need for novel therapeutics to treat this disease. We assessed the effect of AMXI-5001, a novel small molecule poly ADP-Ribose polymerase (PARP) inhibitor and microtubule polymerization inhibitor on tumor growth inhibition in both in-vitro and in-vivo murine models. We found that AMXI-5001 was the most potent growth inhibitor of 8 out of 9 different esophageal carcinoma cell lines compared to other clinically available PARP inhibitors, Olaparib, Niraparib, Rucaparib, and Talazoparib. We then confirmed the previously described mechanism of action of AMXI-5001 as a PARP-inhibitor and microtubule polymerization inhibitor using both a PARP trapping assay and immunofluorescence. To further assess AMXI-5001s potential as a therapeutic for esophageal carcinoma we evaluated the effect of AMXI-5001 in combination with standard chemotherapy agents, Cisplatin and 5 Fluorouracil. We showed that AMXI-5001 synergistically inhibits growth in KYSE-70, a squamous esophageal cell line in combination with these drugs. In addition, we found that AMXI-5001 was an effective radiosensitizer, and squamous esophageal carcinoma cell lines treated 24 hours prior to external beam radiation showed significantly more growth inhibition compared to controls. Finally, we assessed the effect of AMXI-5001 monotherapy and in combination with radiotherapy in a xenograft mouse model implanted with subcutaneous KYSE-70 cells. Compared to vehicle control, and those treated with either AMXI-5001 alone or radiation alone, mice treated with both AMXI-5001 and radiation had significant tumor response. In conclusion, AMXI-5001 is an orally bioavailable dual-action PARP and microtubule polymerization inhibitor that holds promise in the treatment of esophageal carcinoma