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Bronchial premalignant lesions (PMLs) are precursors of lung squamous cell carcinoma, but have variable outcome, and we lack tools to identify and treat PMLs at risk for progression to cancer. Here we report the identification of four molecular subtypes of PMLs with distinct differences in epithelial and immune processes based on RNA-Seq profiling of endobronchial biopsies from high-risk smokers. The Proliferative subtype is enriched with bronchial dysplasia and exhibits up-regulation of metabolic and cell cycle pathways. A Proliferative subtype-associated gene signature identifies subjects with Proliferative PMLs from normal-appearing uninvolved large airway brushings with high specificity. In progressive/persistent Proliferative lesions expression of interferon signaling and antigen processing/presentation pathways decrease and immunofluorescence indicates a depletion of innate and adaptive immune cells compared with regressive lesions. Molecular biomarkers measured in PMLs or the uninvolved airway can enhance histopathological grading and suggest immunoprevention strategies for intercepting the progression of PMLs to lung cancer.

Rab1A expression is associated with malignant phenotypes in several human tumors; however, the role of Rab1A in lung cancer is still unclear. In this study, we attempted to establish the role of Rab1A in major human lung cancer subtypes. Rab1A expression in different histological types of human lung cancer was analyzed in lung cancer tissues with paired adjacent noncancerous tissues and a large panel of lung cancer cell lines. The effect of Rab1A expression on multiple cancer-associated signaling pathways was also examined. The results demonstrated that Rab1A was significantly overexpressed in the different histological types of lung cancer as compared to non-cancerous tissues, and Rab1A expression was correlated with tumor volume and stage. In a large panel of lung cancer cell lines, high Rab1A expression was observed as compared to a normal lung/bronchus epithelial cell line. However, Rab1A protein levels were not correlated with mTORC1 (P-S6K1), mTORC2 (P-AKT), MEK (P-ERK), JNK (P-c-Jun) or p38MAPK (P-MK2) signaling. Rab1A knockdown had no effect on mTOR signaling or cell growth. These data suggested that Rab1A may be involved in the pathogenesis of human lung cancer in an mTOR- and MAPK-independent manner., Competing Interests: The authors declare that they have no competing interests.

Genetic variants of miRNAs that target DNMTs and MBDs involved in DNA methylation were scanned with current databases, and 35 miRSNPs in 22 miRNA genes were identified. The aim of the study was to determine the association between these variants of miRNA genes and lung cancer (LC). DNA samples were isolated from blood samples and genotyped using a Sequenom MassARRAY System. An association between the rs188912830 gene variant of miR3202 that targets the MeCP2 protein and LC was indicated in both subtypes. The presence of the C-allele in patients with LC and its subtypes was significantly lower, and the absence of the C-allele was determined to increase the risk of LC by 7,429-times compared to the presence (p=0,010). The rs318039 gene variant of miR1274 that targets DNMT3b was found to be associated with LC subtypes. When allele distributions were compared, the numbers of individuals with the C-allele were significantly lower in the NSCLC and SCLC groups. No significant associations were found for the rs72563729 variant of the miR200b gene that targets DNMT3a or for the rs145416750 variant of the miR513c gene that targets TRDMT1. The other 33 variants were found to be ancestral genotypes. Consequently, rs188912830 and rs318039 variations were associated with LC subtypes. Importantly, this study is the first to indicate the functional characterisation of miRSNPs of genes that target DNA methylation.

Hyalinizing clear cell carcinoma (HCCC) has only been described in salivary glands of the head and neck. We report a 38-year-old man with a 2.6-cm lung tumor that was growing in a peribronchial location and had morphologic features of HCCC. The tumor cells expressed cytokeratin 7 and keratin AE1/AE3, and the vast majority of tumor cells marked also with p63 and p40. They were negative for cytokeratin 20, S-100, smooth muscle actin, napsin A, and thyroid transcription factor-1. Fluorescence in situ hybridization revealed Ewing Sarcoma Breakpoint Region 1 (EWSR1) rearrangement, and reverse-transcription polymerase chain reaction confirmed the presence of the EWSR1-Activating Transcription Factor 1 (ATF1) fusion transcript, which was subsequently sequenced. The morphologic, immunophenotypic, cytogenetic, and molecular findings together with the patient's history and location of the tumor support a diagnosis of primary pulmonary HCCC of bronchial submucosal gland origin. It is our understanding that this is the first report of HCCC arising as a primary tumor outside the head and neck region., (Copyright © 2015 Elsevier Inc. All rights reserved.)

We present the case of a patient with rapidly accelerated fibrosarcoma gene F (BRAF) mutated adenocarcinoma of the lung, responding to BRAF inhibitor dabrafenib after progressing on vemurafenib followed by docetaxel. The present case illustrates the potential benefit of successful rechallenge with a BRAF inhibitor, a well known phenomenon observed in other oncogenic driven molecular subtypes of non-small cell lung cancer (NSCLC) such as epidermal growth factor receptor mutation. Rechallenge with a BRAF inhibitor in BRAF mutated NSCLC should be considered, particularly in the absence of alternative therpateutic options., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

We show that expression of the microtubule depolymerizing kinesin KIF2C is induced by transformation of immortalized human bronchial epithelial cells (HBEC) by expression of K-Ras(G12V) and knockdown of p53. Further investigation demonstrates that this is due to the K-Ras/ERK1/2 MAPK pathway, as loss of p53 had little effect on KIF2C expression. In addition to KIF2C, we also found that the related kinesin KIF2A is modestly upregulated in this model system; both proteins are expressed more highly in many lung cancer cell lines compared to normal tissue. As a consequence of their depolymerizing activity, these kinesins increase dynamic instability of microtubules. Depletion of either of these kinesins impairs the ability of cells transformed with mutant K-Ras to migrate and invade matrigel. However, depletion of these kinesins does not reverse the epithelial to mesenchymal transition (EMT) caused by mutant K-Ras. Our studies indicate that increased expression of microtubule destabilizing factors can occur during oncogenesis to support enhanced migration and invasion of tumor cells.

DNA methylation is an early event in bronchial carcinogenesis and increased DNA methyltransferase (DNMT)1 protein expression is a crucial step in the oncogenic transformation of epithelia. Here, we investigate the role of class I histone deacetylases (HDAC) 1 to 3 in the stabilization of DNMT1 protein and as a potential therapeutic target for lung cancer chemoprevention. Long-term exposure of immortalized bronchial epithelial cells (HBEC-3KT) to low doses of tobacco-related carcinogens led to oncogenic transformation, increased HDAC expression, cell-cycle independent increased DNMT1 stability, and DNA hypermethylation. Overexpression of HDACs was associated with increased DNMT1 stability and knockdown of HDACs reduced DNMT1 protein levels and induced DNMT1 acetylation. This suggests a causal relationship among increased class I HDACs levels, upregulation of DNMT1 protein, and subsequent promoter hypermethylation. Targeting of class I HDACs with valproic acid (VPA) was associated with reduced HDAC expression and a profound reduction of DNMT1 protein level. Treatment of transformed bronchial epithelial cells with VPA resulted in reduced colony formation, demethylation of the aberrantly methylated SFRP2 promoter, and derepression of SFRP2 transcription. These data suggest that inhibition of HDAC activity may reverse or prevent carcinogen-induced transformation. Finally, immunohistochemistry on human lung cancer specimens revealed a significant increase in DNMT1, HDAC1, HDAC2, and HDAC3 expression, supporting our hypotheses that class I HDACs are mediators of DNMT1 stability. In summary, our study provides evidence for an important role of class I HDACs in controlling the stability of DNMT1 and suggests that HDAC inhibition could be an attractive approach for lung cancer chemoprevention.

This chapter summarizes the current knowledge on gene copy number changes found in lung tumors, and their application in the diagnosis, prognostication, and prediction of response to chemotherapy. Examples of the identification of specific "driver" oncogenes within amplified DNA segments are described. A model of how array-CGH could be integrated clinically into the routine workup of lung cancers in clinical laboratory is proposed.

Lung cancer and chronic obstructive lung disease (COPD) are two common fatal diseases. Apart from their common link to tobacco, these two diseases are usually considered to be the result of separate distinct mechanisms. In the past 15 years, numerous studies have produced arguments in favour of a relationship between these two pathologies that goes beyond a simple addition of risk factors. At the epidemiological level, there are data that demonstrate an increased incidence of bronchial carcinoma in patients with COPD. The links between these two pathologies are still unexplained but there are numerous arguments supporting a common physiopathology. Common genetic and epigenetic abnormalities, mechanical factors and signalisation pathways have been quoted. COPD and lung cancer appear to be two diseases possessing a genetic basis that creates a predisposition to environmental or toxic assaults, resulting in a different clinical manifestation in each disease. Consequently, improvements in the management of these two diseases will involve a more intensive investigation of their physiopathology, and require a closer collaboration between research centres and clinical units., (Copyright © 2012 SPLF. Published by Elsevier Masson SAS. All rights reserved.)

Purpose: The purpose of this study was to examine whether the epidermal growth factor receptor (EGFR) may be used as a general target to modulate DNA double strand break (DSB) repair in tumor cells., Material and Methods: Experiments were performed with human tumor cell lines A549, H1299 and HeLa and primate cell line CV1. EGF, ARG and TGFα were used for EGFR activation, cetuximab or erlotinib for inhibition. Overall DSB repair was assessed by γH2AX/53BP1 co-immunostaining and non-homologous end-joining (NHEJ) and homologous recombination (HR) by using NHEJ and HR reporter cells; cell cycle distribution was determined by flow cytometry and protein expression by Western blot., Results: EGFR activation was found to stimulate overall DSB repair as well as NHEJ regardless of the ligand used. This stimulation was abolished when EGFR signaling was blocked. This regulation was found for all cell lines tested, irrespective of their p53 or K-Ras status. Stimulation and inhibition of EGFR were also found to affect HR., Conclusions: Regulation of DSB repair by EGFR involves both the NHEJ and HR pathway, and appears to occur in most tumor cell lines regardless of p53 and K-Ras mutation status., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Smoking status is essential to know when taking care of a lung cancer patient. Never-smoking patients account for 15% of lung cancer patients, more often women and adenocarcinoma. Environmental tobacco smoke and occupational exposure could be important risk factors. Lung cancer in never-smoker appears to be a distinct entity from lung cancer in smoker, with specific molecular characteristics such as frequent EGFR mutations. New molecular targets are on investigation, such as EML4-ALK translocation. Treatment of lung cancer in never-smoker is getting different from that of smoker with more efficacy of molecular targeted therapies., (Copyright © 2011. Published by Elsevier Masson SAS.)

In patients up to 70 years of age with colon carcinoma stage III adjuvant chemotherapy with infusions of fluorouracil (5-FU) or oral capecitabine combined with oxaliplatin should be the standard method. A new standard for the palliative treatment of Her2/newly positive advanced gastric cancer and cancer at the gastro-esophageal junction is the administration of trastuzumab combined with chemotherapy. Patients with high-risk soft tissue sarcoma can be helped, in addition to surgical resection and subsequent radiotherapy, by neoadjuvant chemotherapy combined with regional deep hyperthermia. For patients with lung cancer additional individualized treatment is about to become routine. In addition to the EGFR mutation status, all non-smokers should in future be tested for aberration in the anaplastic lymphoma kinase (ALK) gene., (© Georg Thieme Verlag KG Stuttgart · New York.)

Multiple endocrine neoplasia type I (MEN1) is a rare hereditary cancer syndrome, which is manifested as a variety of endocrine and non-endocrine tumours and lesions caused by specific germline mutations of the MEN1 gene, a tumour suppressor gene. The detection of these germline mutations allows the early identification of affected, possibly still asymptomatic patients. The combined use of genetic and clinical tools for the diagnosis of MEN1-associated tumours substantially improves both the course of the disease and the quality of life of affected patients. This review summarizes the relevant morphological and clinical features of MEN1-associated endocrine and non-endocrine neoplasms and lesions.

The aim of this study was to explore the histogenesis and carcinogenesis of pulmonary cancer induced by N-nitrosopiperidine (NPIP) in mice. NPIP is a form of N-nitrosamine found in tobacco smoke, which has been shown to be a genotoxic chemical as well as a mutagenic compound for inducing chromosome aberrations and severe clastogenicity. In this study, 80 BALB/C strain mice were injected with 0.2 mmol/kg NPIP intraperitoneally for 8 weeks, and experiments were conducted for a further 16 weeks. For the control group, 40 mice were injected with an equal volume of 0.9% NaCl. Pulmonary tissues and tumors in the NPIP-treated group were examined by light microscopy and transmission electron microscopy and compared with the control group at 4-week intervals. The mRNA levels of p53 (mutant), bcl-2, c-myc, ras, and subunits of telomerase - telomerase reverse transcriptase (TERT) and an RNA component, TR - were assayed by mPCR or RT-PCR. Twenty-two mice in the experimental group were found to develop pulmonary tumors, but none in the control group. All tumors found in the experimental group originated from alveolar type II epithelial cells. In addition, 6 of the 22 mice also developed tumors of bronchogenic origin. The expression of p53, bcl-2, c-myc, ras, and the subunits of telomerase were found to increase in all pulmonary tissues and tumors formed thereafter upon NPIP treatment. In summary, NPIP-induced mouse lung tumors exhibited morphological changes during carcinogenesis, which may be the consequence of overexpression of some genes associated with the development of carcinoma and changes in subunits of telomerase. This mouse model of lung tumor formation may be a useful tool to delineate the histogenesis and carcinogenesis of human pulmonary cancer.

Purpose: Some 85% of lung cancers are smoking related. Here, we investigate the role of serine protease HtrA3 in smoking-related lung cancer., Experimental Design: We assess HtrA3 methylation and its corresponding expression in the human bronchial cell line BEAS-2B following cigarette smoke carcinogen treatment, in lung cancer cell lines and in primary lung tumors from light, moderate, and heavy smokers. We also show the effects of HtrA3 downregulation on MTT reduction and clonogenic survival with etoposide and cisplatin treatment and the corresponding effects of HtrA3 re-expression during treatment., Results: We show for the first time that HtrA3 expression is reduced or completely lost in over 50% of lung cancer cell lines and primary lung tumors from heavy smokers. Treatment of HtrA3-deficient cell lines with 5-aza-2'-deoxycytidine resulted in a dose-dependent increase in HtrA3 transcription. Further, sequence analysis of bisulfite-modified DNA from lung cancer cell lines and from primary lung tumors showed an increased frequency of methylation within the first exon of HtrA3 with a corresponding loss of HtrA3 expression, particularly in tumors from smokers. In BEAS-2B, treatment with the cigarette smoke carcinogen 4-(methylnitrosamino)-I-(3-pyridyl)-1-butanone resulted in HtrA3 downregulation with a corresponding increase in methylation. Additional studies indicate resistance to etoposide and cisplatin cytotoxicity as a functional consequence of HtrA3 loss. Finally, immunohistochemical analysis of primary lung tumors revealed a strong correlation between low HtrA3 expression and heavy smoking history., Conclusions: Collectively, these results suggest that cigarette smoke-induced methylation of HtrA3 could contribute to the etiology of chemoresistant disease in smoking-related lung cancer.

Introduction: Lung cancer is the commonest fatal malignancy in the developed world. Survival rates for lung cancer have not changed significantly over the past 30 years. Sources of data This report is a systematic review of the literature on our current understanding of lung cancer biology. Searches were carried out using PUBMED. 1990-2010., Areas of Agreement: A concerted effort to reduce cigarette smoking and nicotine addiction is required. A better understanding of the biology of lung cancer will lead to the identification of earlier diagnostic markers and improved therapy., Areas of Controversy: How chronic inflammatory disorders such as COPD and lung fibrosis contribute to lung cancer development is incompletely understood., Growing Points: Developing novel biological agents to target lung cancer. New microarray-based technologies provide new methods for predicting prognosis and response to treatment., Areas Timely for Developing Research: Developing strategies to target lung cancer stem cells may provide a novel approach for treating drug resistant disease.

Previously, we found that oncogenically transformed cells had fewer filopodia and more large, p21-activated kinase (PAK)-dependent features than normal cells. These large protrusions (LPs) were increased in cells expressing RhoA(N19) with Cdc42-associated kinase (ACK). Here, we determine how GTPase-mediated mechanisms of focal contact (FC) regulation affect these protrusions. Constructs encoding various proteins were introduced into cells which were then studied by microscopy and computerized image processing and analysis. Constructs that prevented PAK recruitment by PAK-interacting exchange factor (PIX) or restricted PAK residence time on FCs decreased both protrusions. Thus, filopodia were also PAK-dependent. A comparison of FC distribution in cells expressing PAK in the presence or absence of PAK kinase inhibitor domain (KID) suggested that PAK enlarged FCs without affecting the prevalence of either protrusion. KID or Nck expression increased LPs but not filopodia. Nck failed to synergize with KID or ACK and RhoA(N19) in enhancing LPs. Nck and KID synergistically enhanced filopodia, possibly because Nck recruited PAK to FCs while KID prevented their dissociation by PAK-mediated autophosphorylation. Coexpression of Nck, ACK, and RhoA(N19) abrogated filopodia and replicated the transformed phenotype. Since Nck recruitment of PAK is implicated in persistence of directional movement, we studied the PAK-Nck interface. Filopodia were eliminated by the Nck PAK-binding domain and LPs by the PAK Nck-binding domain. The results suggested that filopodia formation has more stringent requirements than LP formation, and Nck and PAK are used differently in the protrusions. Loss of filopodia in transformed cells may reflect defective regulation of GTPase mechanisms.

Heavy smokers with central type squamous cell carcinoma (SCC) frequently have multiple cancerous lesions in the bronchus. Autofluorescence bronchoscopy (AFB) is useful in the detection of early bronchogenic cancer and dysplastic lesions. We investigated the loss of heterozygosity (LOH) and microsatellite instability (MSI) and expression of four proteins in 13 early stage SCC (early SCC) and 9 squamous dysplasia detected by AFB and 19 cases of surgically resected invasive SCC (invasive SCC). In early SCC and squamous dysplasia, LOH/MSI of chromosome 1p36 was found in 62 and 33%, respectively, and of 9p21 in 54 and 63%, respectively. TAp73 expression of early SCC and squamous dysplasia was lower than that of normal bronchial epithelium, and p16 expression was not detectable in these lesions. These results suggested that the genetic abnormalities had already developed in the early stage of carcinogenesis of SCC, including squamous dysplasia. The AFB system was able to reveal abnormal autofluorescence in these precancerous lesions, including squamous dysplasia.

Background: Chemotherapy often leads to encouraging responses in lung cancer. But, in the course of the treatment, resistance to chemotherapy ultimately limits the life expectancy of the patient. We aimed at investigating if treatment with cisplatin alters the intracellular Ca2+-homeostasis of lung cancer cells and how this may be related to cisplatin resistance., Methods: The squamous cell lung carcinoma cell line EPLC M1 and the small cell lung cancer cell line H1339 were exposed to cisplatin analogue to the in vivo pharmacokinetics. Changes in the cytoplasmic Ca2+-concentration ([Ca2+]c) were recorded using fluorescence microscopy. Protein expression was quantified using immuno-fluorescence and Western Blot analysis. Changes in gene expression were accomplished by small-interfering (si) RNA techniques., Results: Four "cycles" of cisplatin led to low level resistance in EPLC and H1339 cells. In the low level resistant cell clones, the Ca2+-content of the endoplasmic reticulum (ER) was decreased. In low level resistant EPLC cells, this was correlated with an increased expression of the inositol-1,4,5-trisphosphate receptor (IP3R). Inhibiting the increased expression of IP3R using siRNA, the low level resistance could be reversed. In low level resistant H1339 cells, the decreased Ca2+-content of the ER was correlated with a decreased expression of sarco/endoplasmic reticulum Ca2+-ATPases (SERCA). Decreasing the expression of SERCA in naïve H1339 cells resulted in low level cisplatin resistance., Conclusion: We conclude that cisplatin therapy leads to a decreased Ca2+-content of the ER thereby inducing low level resistance. This is caused by upregulation of the IP3R in EPLC and decreased expression of SERCA in H1339 cells.

Aim: To evaluate by immumohistochemistry the presence of DR subtype 2 (D2R) in well differentiated NETs of different sites and in normal islet cells., Background: Recent data in vitro and in vivo support that dopaminergic drugs might exert an inhibitory effect on hormone secretion and, possibly, on tumor growth in neuroendocrine tumors (NET)s. Their potential therapeutic role needs the demonstration of dopamine receptors (DR) in tumor cells. Little is known on the expression of DR in NETs., Results: 85% of samples (100% of bronchial carcinoids and 93% of islet cell tumors) showed positivity for D2R; intensity of immunoreaction in NETs was similar or higher than in pituitary (54% and respectively 31% of cases). D2R positivity in more than 70% of tumor cells was observed in 46% of samples. Same intensity of D2R-immunoreactivity was found in pituitary and normal islet cells. No differences in D2R expression were recorded on considering tumor grading, size, proliferative activity, presence of metastases, endocrine activity and gender. A significant difference (62.5% vs 96.4%, p = 0.039) was observed in the prevalence of D2R expression between patients with more aggressive tumors and patients without recurrence/progression of disease during follow-up., Methods: 46 NET samples from 44 patients and normal endocrine pancreatic tissue were studied. D2R-staining was performed on NETs and compared with six non-secreting pituitary adenomas and related to clinical-pathological data., Conclusion: The present data demonstrate a high expression of D2R in NETs; this finding is of clinical relevance in view of the potential role of dopaminergic drugs in inhibiting secretion and/or cell proliferation in NETs.

Most cancer genomes are characterized by the gain or loss of copies of some sequences through deletion, amplification or unbalanced translocations. Delineating and quantifying these changes is important in understanding the initiation and progression of cancer, in identifying novel therapeutic targets, and in the diagnosis and prognosis of individual patients. Conventional methods for measuring copy-number are limited in their ability to analyse large numbers of loci, in their dynamic range and accuracy, or in their ability to analyse small or degraded samples. This latter limitation makes it difficult to access the wealth of fixed, archived material present in clinical collections, and also impairs our ability to analyse small numbers of selected cells from biopsies. Molecular copy-number counting (MCC), a digital PCR technique, has been used to delineate a non-reciprocal translocation using good quality DNA from a renal carcinoma cell line. We now demonstrate microMCC, an adaptation of MCC which allows the precise assessment of copy number variation over a significant dynamic range, in template DNA extracted from formalin-fixed paraffin-embedded clinical biopsies. Further, microMCC can accurately measure copy number variation at multiple loci, even when applied to picogram quantities of grossly degraded DNA extracted after laser capture microdissection of fixed specimens. Finally, we demonstrate the power of microMCC to precisely interrogate cancer genomes, in a way not currently feasible with other methodologies, by defining the position of a junction between an amplified and non-amplified genomic segment in a bronchial carcinoma. This has tremendous potential for the exploitation of archived resources for high-resolution targeted cancer genomics and in the future for interrogating multiple loci in cancer diagnostics or prognostics., ((c) 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.)

We present the chromosomal aberrations in a case of synchronous extranodal marginal zone B-cell lymphoma and bronchogenic adenocarcinoma with bronchioloalveolar features. Using fluorescence in situ hybridization, we identified deletion of the immunoglobulin heavy chain gene in the lymphomatous component, but not the carcinomatous component. The presence of differing genetic compositions suggests a biclonal environment composed of 2 distinct neoplastic processes.

Up to 10% of patients with non-small cell lung carcinoma (NSCLC) achieve an objective response to EGFR tyrosine kinase inhibitors (EGFR-TKI) such as erlotinib or gefitinib. This rate of response is related to non-smoker status, female gender, adenocarcinoma subtype, and Asian ethnicity. Molecular analysis showed that EGFR tyrosine kinase domain somatic mutations appear to be a strong predictor of response to EGFR-TKI. The L858R point mutation and the E746-A750 deletion represent 90% of the mutations encountered in responding patients. The amplification of EGFR gene also seems to be predictive of the response to EGFR-TKI, whereas T790M point mutation induces secondary resistance to EGFR-TKI. Nevertheless, objective responses or strong long-term stabilizations are observed in patients without any EGFR abnormality. Thus, the assessment of the EGFR status in patients with NSCLC remains controversial for clinical practice. The assessment of EGFR abnormalities should be targeted to identify reliable biomarkers of the NSCLC response to EGFR-TKI. This review presents the current knowledge on predictive biomarkers of NSCLC response to EGFR-TKI and the methods available for the assessment of EGFR status.

Background: Lung carcinogenesis is a multistep process of accumulation of genetic changes, including loss of heterozygosity (LOH), and precedes phenotypic transformation of the bronchial mucosa. The activity of telomerase, correlating with the hTERT mRNA expression, is detectable in a majority of neoplasms. In this study, the frequency of LOH and hTERT expression in bronchial mucosa of heavy smokers in bronchoscopic biopsies was analyzed., Methods: LOH was examined in 122 bronchial specimens from 81 smokers (67 normal mucosa/bronchitis, 12 squamous metaplasia, 28 dysplasia, 15 bronchogenic carcinoma specimens) by polymerase chain reaction (PCR) and capillary electrophoresis by using 7 fluorescence-labeled markers matching 5 chromosomal regions. hTERT expression was analyzed in 87 specimens (45 normal mucosa/bronchitis, 12 squamous metaplasia, 18 dysplasia, 12 bronchogenic carcinoma specimens) by real-time quantitative reverse-transcription PCR., Results: LOH was detected in at least 1 chromosomal region in 51 of 122 (41.8%) specimens; the incidence in normal bronchial mucosa and preneoplastic lesions was similar (20%-40%); a substantial rise (87%) occurred in carcinomas. The median normalized hTERT(N) values were 6.67 in normal epithelium/chronic bronchitis, 18.38 in squamous metaplasia, 13.31 in epithelial dysplasia, and 75.46 in carcinomas. These results were significantly different (P=.0036). With an increasing number of LOH, the median value of hTERT(N) expression rose, but hTERT was expressed also in tissue samples without any LOH detection., Conclusions: Results indicated that hTERT expression, together with LOH, represent early events in lung carcinogenesis, as both were detected in precancerous lesions and in normal epithelium of heavy smokers.

Currently available cytotoxic chemotherapy is ineffective for treating bronchogenic carcinoma, and this is partly due to unpredictable inter-tumor variation in resistance. For example, tumors with inactivating p53 mutations or deletions are less likely to respond to certain chemotherapeutics. However, even if p53 is intact, a tumor may be unresponsive if defects in other p53 pathway genes compromise apoptosis. In an effort to identify biomarkers that better predict response to camptothecin, we investigated the association of CPT-11 (irinotecan)-induced cytotoxicity (IC50) with apoptosis or expression of genes upstream or downstream of p53 in cell lines that retain wild-type p53. CPT-11 response was greater in cell lines with higher baseline apoptosis (p<0.05). In addition, the interactive transcript abundance index (ITAI) [c-myc*p73alpha]/[p21*Bcl-2] was directly correlated with baseline apoptosis (p<0.01) and CPT-11 response (p<0.05). The ITAI was also correlated with CPT-11 response among cell lines derived from a variety of tissues that had inactivating p53 mutations or deletions, supporting its applicability for predicting response to camptothecins in other tissues regardless of p53 status.

This review highlights the numerous molecular biology findings in the field of lung cancer with potential therapeutic impact in both the near and distant future. Abundant pre-clinical and clinical data indicate that BRCA1 mRNA expression is a differential modulator of chemotherapy sensitivity. Low levels predict cisplatin sensitivity and antimicrotubule drug resistance, and the opposite occurs with high levels. The main core of recent research has centered on epidermal growth factor receptor (EGFR) mutations and gene copy numbers. For the first time, EGFR mutations have been shown to predict dramatic responses in metastatic lung adenocarcinomas, with a threefold increase in time to progression and survival in patients receiving EGFR tyrosine-kinase inhibitors. Evidence has also been accumulated on the crosstalk between estrogen and EGFR receptor pathways, paving the way for clinical trials of EGFR tyrosine-kinase inhibitors plus aromatase inhibitors. Understanding the relevance of these findings can help to change the clinical practice in oncology towards customizing chemotherapy and targeted therapies, leading to improvement both in survival and in cost-effectiveness.

Adenoviral immuno-gene therapy using interferon-beta has been effective in an orthotopic model of lung cancer. However, pulmonary inflammation induced by adenoviral (Ad) vectors will almost certainly limit the maximally tolerated dose. On the other hand, the strong innate immune response generated by the vector may be helpful in initiating the adaptive immune response required for efficacy. The goals of this study were to develop an effective approach to inhibit Ad.IFNbeta-mediated acute pulmonary inflammation and to determine whether this reduction of Ad-mediated inflammation decreased the therapeutic efficacy of Ad.IFNbeta in a mouse model of bronchioloalveolar cancer. Our data show that anti-TNF-alpha antibodies can blunt the innate pulmonary immune response induced by Ad vectors, even in sensitized animals. However, this effect also inhibited the ability of the animal to generate anti-tumor immune responses and reduced survival in an orthotopic lung cancer model responsive to Ad.IFNbeta treatment. Interestingly, in a flank model of tumor using a cell line derived from the lung tumor, TNF-alpha blockade did not inhibit efficacy. These data suggest that the innate immune response to adenovirus in the lung may be important in immuno-gene therapy of lung cancer. Therapeutic application of anti-inflammatory therapy in immuno-gene therapy strategies should thus be undertaken with caution.

Given previous work showing that an adenoviral vector expressing IFN-beta (Ad.IFNbeta) was highly effective in eradicating i.p. mesothelioma tumors, the antitumor efficacy of this agent was evaluated in an orthotopic model of bronchogenic adenocarcinoma of the lung. These transgenic mice have a conditionally expressed, oncogenic K-rasG12D allele that can be activated by intratracheal administration of an adenovirus expressing Cre recombinase (Ad.Cre). K-rasG12D mutant mice were given Ad.Cre intranasally to activate the oncogene. Mice were then given 10(9) plaque-forming units of a control vector (Ad.LacZ) or Ad.IFNbeta intranasally 3 and 4 weeks later, a time when lung tumors had been established. Cells derived from K-ras-mutated lung tumors were also grown in the flanks of mice to study mechanisms of therapeutic responses. In two separate experiments, untreated tumor-bearing mice all died by day 57 (median survival, 49 days). Ad.LacZ-treated mice all died by day 71 (median survival, 65 days). In contrast, 90% to 100% of mice treated with Ad.IFNbeta were long-term survivors (>120 days; P < 0.001). In addition, immunity to re-challenge with tumor cells was induced. In vitro and flank tumor studies showed that Ad.IFNbeta induced direct tumor cell killing and that depleting natural killer or CD8+ T cells, but not CD4+ T cells, with antibodies attenuated the effect of Ad.IFNbeta. These studies, showing remarkable antitumor activity in this orthotopic lung cancer model, provide strong preclinical support for a trial of Ad.IFNbeta to treat human non-small cell lung cancer.

Early lung cancer screening failed to reduce lung cancer mortality. New techniques such as autofluorescence bronchoscopy (AF) and the identification of specific genetic alteration might change future outcomes of lung cancer screening. It was the aim of our study to combine p53 analysis with white-light bronchoscopy (WL) or WL and AF to improve the diagnostic yield in a series of 36 patients with histologically proven lung cancer, pulmonary metastasis or suspected lung cancer. - Endobronchial sites were analysed by WL (n = 71), AF (Storz) (n = 34), histopathology (n = 71) and p53 mutations were examined by SSCP analysis on additional biopsies (n = 69). The overall frequency of cancerous lesions was 19, of which 14 were macroscopically visible lesions. The addition of p53 and autofluorescence improved the yield to 17 of 19 cases. In 7 preinvasive lesions (dysplasia/metaplasia) 4 were identified macroscopically and 5 of 7 lesions by all 3 methods. In the WL/p53 group the diagnostic yield was 7 of 9 cancerous lesions compared to 10 of 10 cancerous lesions in the AF group. It should be noted that all methods were associated with false positive results. However, the combination of conventional with autofluorescence bronchoscopy and mutation analysis is a promising approach which is applicable to clinical routine and may be further enhanced by the inclusion of a panel of markers of tumour progression.

Background: Cell proliferation control depends in part on the carefully ordered regulation of transcription factors. The p53 homolog p73, contributes to this control by directly upregulating the cyclin dependent kinase inhibitor, p21waf1/cip1. E2F1, an inducer of cell proliferation, directly upregulates p73 and in some systems upregulates p21 directly. Because of its central role in controlling cell proliferation, upregulation of p21 has been explored as a modality for treating bronchogenic carcinoma (BC). Improved understanding of p21 transcriptional regulation will facilitate identification of BC tissues that are responsive to p21-directed therapies. Toward this goal, we investigated the role that E2F1 and p73 each play in the transcriptional regulation of p21., Results: Among BC samples (N = 21) p21 transcript abundance (TA) levels varied over two orders of magnitude with values ranging from 400 to 120,000 (in units of molecules/106 molecules beta-actin). The p21 values in many BC were high compared to those observed in normal bronchial epithelial cells (BEC) (N = 18). Among all BC samples, there was no correlation between E2F1 and p21 TA but there was positive correlation between E2F1 and p73alpha (p < 0.001) TA. Among BC cell lines with inactivated p53 and wild type p73 (N = 7) there was positive correlation between p73alpha and p21 TA (p < 0.05). Additionally, in a BC cell line in which both p53 and p73 were inactivated (H1155), E2F1 TA level was high (50,000), but p21 TA level was low (470). Transiently expressed exogenous p73alpha in the BC cell line Calu-1, was associated with a significant (p < 0.05) 90% increase in p21 TA and a 20% reduction in E2F1 TA. siRNA mediated reduction of p73 TA in the N417 BC cell line was associated with a significant reduction in p21 TA level (p < 0.01)., Conclusion: p21 TA levels vary considerably among BC patients which may be attributable to 1) genetic alterations in Rb and p53 and 2) variation in TA levels of upstream transcription factors E2F1 and p73. Here we provide evidence that p73 upregulates p21 TA in BC tissues and upregulated p21 TA may result from E2F1 upregulation of p73 but not from E2F1 directly.

A familial and personal history of cancer might be associated with a more aggressive cancerous disease. This study was carried out on 1277 consecutive lung cancer (LC) patients, seen from January 1989 to October 2002 in a single institution. A set of 31 clinical laboratory, radiological and pathological variables was recorded prospectively for all patients. In addition, both the number of first-degree blood-relatives with cancer (lung and non-lung cancers) and the personal history of previously cured cancers were noted. There were 368 patients (28.8% of the sample) who had one first-degree relative with cancer (112, 8.7% of the sample with LC), 100 (7.8%) had two first-degree relatives (six with LC) and 31 (2.4%) had three or more relatives affected (four with LC). In total, 1142 patients (89.4% of the sample) have never been treated for another cancer; the remaining 135 patients (10.6%) had already been diagnosed with a variety of tumours, including head and neck cancer (36 patients, 2.8%), bladder cancer (33 patients, 2.6%), colorectal cancer (24 patients, 1.9%), breast cancer (seven patients, 0.6%), melanoma (five patients, 0.4%), skin (five patients, 0.4%) and prostate cancer (five patients, 0.4%). Among the variables studied, none was found to be significantly associated with a personal and/or family history of cancer. Survival expectancy was similar among patients with or without a familial or personal history of cancer. A familial and a personal history of cancer are common features in LC, but are not of clinical significance.

Purpose: To test a stimulatory effect of the radioprotector Bowman Birk protease inhibitor (BBI) upon DNA repair processes., Materials and Methods: An effect of BBI upon DNA repair was investigated by quantification of radiation-induced dicentric chromosomes. Sensitivity to ionizing radiation was determined by clonogenic survival assay. Quantification of activity of the DNA-dependent kinase was performed by immunoprecipitation and phosphorylation of a TP53-derived peptide., Results: The formation of radiation-induced dicentric chromosomes was reduced significantly after pretreatment of cells with BBI. By using a cell line with an inducible expression of a mutated TP53, it was shown that the BBI-mediated reduction of dicentric chromosome formation depended on the presence of wild-type TP53. To get further insights into the molecular mode of action of BBI, activity of the DNA-dependent protein kinase (DNA-PK) was quantified. BBI treatment resulted in a stimulation of basal (DNA-PK) activity. In SCID mouse fibroblasts deficient in DNA-PK activity, BBI failed to reduce the amount of radiation-induced dicentric chromosomes and the radioprotective effect was absent. Likewise, cells expressing mt.TP53 did not show radioprotection by BBI., Conclusions: It was observed that BBI exerts its radioprotective effect by a reduction of incorrect DNA repair, resulting in a reduced amount of dicentric chromosomes. This effect on the fidelity of DNA repair is TP53 dependent and correlated with induction of DNA-PK activity.

Background: Glutathione S-transferase mu (GST mu) enzyme detoxifies carcinogens in tobacco smoke. We assessed the clinical usefulness of serum assay of GSTm in determining the risk for lung cancer., Materials and Methods: Fifty-nine patients with primary lung cancer and 32 control cases were enrolled. GSTm detection was performed by the method ELISA., Results: GSTm enzyme positivity rate of the patient group (39%) was significantly lower than the control group (59.4%) (p < 0.05). The GSTm positivity rates were 28.6% for the non-smoker patients with a cancer history of relatives, 31.6% for the smoker patients with the cancer history of relatives, 14.6% for the non-smoker patients with the lung cancer history of relatives and 16.7% for the smoker patients with the lung cancer history of relatives., Conclusions: We concluded that if the people lacking GSTm are smokers and have a cancer and/or lung cancer history among their relatives, they would challenge a greater risk of lung cancer than the individuals having GST mu isoenzyme.

Lung cancer is a major health-care problem in industrialized countries. With reference to its therapeutic consequences and major histological variations, it is divided into two subgroups - SCLC (small-cell lung cancer) and NSCLC (non-small-cell lung cancer). As an important factor of cell-cell and cell-substratum interaction, cell adhesion molecules (CAMs) seem to play a key role in tumor-cell migration and invasion that lead to metastases. We investigated human lung tumor cell lines established from histologically documented neoplastic lesions taken in our operating theater. Immunohistological screening showed differences in E-cadherin expression with no clear predominance of SCLC or NSCLC cell lines. Using an invasion model with Matrigel Matrix and a migration assay, we could demonstrate a more aggressive behavior pattern in E-cadherin-negative cell lines. We transfected E-cadherin cDNA into a formerly negative cell line showing strong invasive behavior in the initial tests in order to investigate the role of E-cadherin in this process. In this study, we examined E-cadherin cDNA transfection in human bronchial carcinoma cells. At present, transfection is stable with a follow-up time of one year. We could demonstrate that cell lines were remarkably less invasive after transfection of E-cadherin in the invasion model with Matrigel Matrix. These results indicate that the E-cadherin CAM plays an important role in lung tumor invasion and metastasis. Further studies are in progress to confirm these findings and to describe a possible role of this CAM in tumor therapy.

Asbestos is a ubiquitous, naturally occurring fiber that has been linked to the development of malignant and fibrotic diseases of the lung and pleura. These diseases may be initiated by injury to epithelial cells and mesothelial cells by asbestos fibers through the formation of reactive oxygen intermediates. Elaboration of oxidants are also a consequence of inflammation, a hallmark of exposure to asbestos after inhalation or injection of asbestos fibers into animals. The type, size, and durability of asbestos fibers may be important in toxicity and pathogenicity of asbestos types. This review discusses the pathways of oxidant generation by asbestos fibers, cell-cell interaction that may initiate and perpetuate inflammation, cytokine release and proliferative responses to asbestos, and cell signaling pathways implicated in these events.

Advances in molecular biology have increased our knowledge of the biology of preneoplastic lesions in the human lung. The recently published WHO lung tumour classification defines three separate lesions that are regarded as preinvasive neoplasia. These are (1) squamous dysplasia and carcinoma in situ (SD/CIS), (2) atypical adenomatous hyperplasia (AAH), and (3) diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIP-NECH). SD/CIS is graded in four stages (mild, moderate, severe, and CIS), based upon the distribution of atypical cells and mitotic figures. Most airways showing SD/CIS demonstrate a range of grades; many epithelia are hard to assess and the reproducibility of this complex system remains to be established. Detailed criteria are, however, welcome and provide an objective framework on which to compare various molecular changes. Alterations in gene expression and chromosome structure known to be associated with malignant transformation can be demonstrated in CIS, less so in dysplasias, but also in morphologically normal epithelium. The changes might be sequential, and their frequency and number increase with atypia. Less is known of the "risk of progression" of SD/CIS to invasive "central" bronchial carcinoma. It may take between one and 10 years for invasion to occur, yet the lesion(s) may be reversible if carcinogen exposure ceases. AAH may be an important precursor lesion for peripheral "parenchymal" adenocarcinoma of the lung: the "adenoma" in an adenoma-carcinoma sequence. There is good morphological evidence that AAH may progress from low to high grade to bronchioloalveolar carcinoma (BAC; a non-invasive lesion by definition). Invasion then develops within BAC and peripheral lung adenocarcinoma evolves. The molecular events associated with this progression are not well understood and studies are hampered by a lack of clear criteria to distinguish high grade AAH from BAC. Nonetheless, as with SD/CIS, the patterns of expression of tumour associated genes are consistent with neoplastic progression. We have little idea of the incidence of AAH in the normal or "smoking" populations. It is found more frequently in cancer bearing lungs, especially in those with adenocarcinoma, and is more common in women. No data are available on the risk of progression of AAH. DIPNECH is an exceptionally rare lesion associated with the development of multiple carcinoid tumours. Almost nothing is known of its biology. Knowledge of these lesions will be crucial in the design and understanding of lung cancer screening programmes, where it is likely that the morphological and, more importantly perhaps, the molecular characteristics of these lesions will provide useful targets for detection and possibly even treatment.

We attempted to develop a new strategy of gene transfer in human metastatic cells avoiding viral vectors. We demonstrated the feasibility of the nlsLacZ gene-liposome (DOTAP) complex transfection in lung cancer cell lines H358 and Calu-1 carrying homozygous deletion of p53 and in primary cultures of human pleural metastatic tumor cells (n = 10). The efficiency of transfection in pleural cells was high with a mean of 78 +/- 22% (range 40-100%) compared to H358 (30%) and Calu-1 cells (50%). In this study, we report that growth of pC53-SN3-transfected Calu-1 and pleural metastatic cells was greatly suppressed whereas neither liposomes or Neo-gene affected cells growth. We tempted to determine whether restoration of wtp53 increased the chemosensitivity of cells that normally lack p53 expression. The pC53-SN3 transfected cells (H358 and Calu-1) were more sensitive to CDDP than the parental cells by 14 and 1.2 fold, respectively. In addition, the sensitization ratio due to the transfection of wtp53 in pleural cells (n = 6) varied from 1.2 to 6 fold. This sensitization remained even 21 days after transfection and was accompanied by increase of p53 positive cells and of the proportion of apoptotic bodies. In conclusion our results suggested that DOTAP is an efficient vector for mediating gene transfer in pleural metastatic cells offering advantages compared to viral vectors, while tumor suppressor genes such as p53 may be good candidates in combination with conventional therapy with CDDP that could be further developed for their use in local cancer gene therapy.

Alveolar type II cells arising in canine bronchial autografts following exposure to 3-methylcholanthrene (MCA) give rise to carcinomas of varying glandular and squamous growth patterns. To study the role of the tumor suppressor gene p53 in this process, sections from progressive lesions were immunostained for p53 protein; microdissected regions were screened for p53 mutations. Adjacent sections were examined for type II cell expression [cuboid cell shape, large roundish nucleus, cytoplasmic staining for surfactant protein A (SP-A)] and proliferating cell nuclear antigen expression. Evidence for an altered p53 function (nuclear staining, missense mutations) was found in most carcinomas of all histologic types and in all grades of bronchial dysplasia, but not in hyperplastic or normal bronchial epithelium. It was primarily associated with the hyperplastic type II cell populations present in the basal zone of the lesions. In addition, we found SP-A staining in hyperplastic (but not in normal) bronchial basal cells. These data suggest that MCA initiates type II cell differentiation through phenotypic selection (basal cells). Inactivation of the p53 gene promotes the clonal expansion of the type II cells into discernible populations of (squamous or glandular) alveolar tumor cells. This in vivo study is the first to show that p53 is involved in a specific pathway leading to bronchogenic carcinoma.

Normal bronchial epithelial cells (NBECs) are at risk for damage from inhaled and endogenous oxidative species and from epoxide metabolites of inhaled polycyclic aromatic hydrocarbons. Epidemiological and in vitro data suggest that interindividual variation in this risk may result from variation in NBEC expression of enzymes that inactivate reactive species by conjugating them to glutathione. Quantitative competitive reverse transcription-PCR was used to measure mRNA levels of glutathione transferases (GSTs) and glutathione peroxidases (GSHPxs) in primary NBECs from subjects with or without bronchogenic carcinoma. Mean expression levels (mRNA/10(3) beta-actin mRNA) in NBECs from 23 subjects without bronchogenic carcinoma compared to those from 11 subjects with bronchogenic carcinoma respectively (in parentheses) were: mGST (26.0, 6.11), GSTM3 (0.29, 0.09), combined GSTM1,2,4,5 (0.98, 0.60), GSTT1 (0.84, 0.76), GSTP1 (287, 110), GSHPx (140, 62.1), and GSHPxA (0.43, 0.34). Levels of GSTP1, GSTM3, and GSHPx were significantly (P < 0.05) lower in NBECs from subjects with bronchogenic carcinoma. Further, the gene expression index formed by multiplying the values for mGST x GSTM3 x GSHPx x GSHPxA x GSTP1 had a sensitivity (90%) and specificity (76%) for detecting NBECs from bronchogenic carcinoma subjects that was better than any individual gene. In cultured NBECs derived from eight individuals without bronchogenic carcinoma and incubated under identical conditions such that environmental effects were minimized, the mean level of expression and degree of interindividual variation for each gene evaluated was less than that observed in primary NBECs. Data from these studies support the hypotheses that (a) interindividual variation in risk for bronchogenic carcinoma results in part from interindividual variation in NBEC expression of antioxidant genes; (b) gene expression indices will better identify individuals at risk for bronchogenic carcinoma than individual gene expression values; and (c) both hereditary and environmental exposures contribute to the level of and interindividual variation in gene expression observed in primary NBECs. Many epidemiological studies have been designed to evaluate risk associated with polymorphisms or gene expression levels of putative susceptibility genes based on measurements in surrogate tissues, such as peripheral blood lymphocytes. Based on data presented here, it will be important to include the assessment of NBECs in future studies. Measurement of antioxidant gene expression in NBECs may identify the 5-10% of individuals at risk for bronchogenic carcinoma. Bronchoscopic sampling of NBECs from smokers and ex-smokers then will allow susceptible individuals to be entered into surveillance and/or chemoprevention studies.

Lung cancer patients suffer a 15% overall survival despite advances in chemotherapy, radiation therapy and surgery. This unacceptably low survival rate is due to the usual finding of advanced disease at diagnosis. Detecting preneoplastic lesions and determining which invasive lesions are prone to metastasize or recur can be formidable tasks. Understanding the molecular events that occur during the multistep process of bronchogenic carcinogenesis may make these tasks more surmountable. Approaches leading to identification of patients susceptible to cancer formation include detection of poor metabolizers of carcinogens, those unable to repair genetic alterations, those with activated oncogenes or inactivated tumor suppressor genes, and those at risk of poor outcomes. Detection may be achieved at the cellular, chromosomal, genetic, or protein level. Novel therapies can then be developed that prevent tumor initiation into and promotion through the multistep carcinogenesis pathway, conversion from preneoplastic into invasive malignancies, and progression into metastasis or recurrences. Therapeutic success of chemoprevention can be followed by changes in molecular marker levels. Blockade of activated tumor-promoting oncogenes or replacement of inactivated tumor-suppressing or apoptosis-promoting genes can be achieved by gene therapy. Development of these novel molecular diagnostic and therapeutic strategies could result in prevention of cancer formation or at least prolongation of disease-free survival., (Copyright 2000 Wiley-Liss, Inc.)

History of cancer among first degree relatives was obtained in 124 patients with bronchogenic carcinoma [probands] and 248 controls, and differences in familial aggregation evaluated by calculation of odds ratio [OR] and their 95 percent confidence intervals [95% CI]. Probands were more likely than controls to have relatives with cancers [OR 1.27, 95% CI 0.49-3.10], both among smokers and nonsmokers [OR 1.31, 95% CI 0.27-6.79 and OR 1.21, 95% CI 0.12-6.16 respectively]. Sisters of probands were particularly at a higher risk [OR 8.72, 95% CI 0.85-430.08]. A genetic component, possibly independent of smoking habits, may be important in the causation of lung cancer.

A small proline-rich protein, SPR1, is overexpressed in squamous metaplasia of bronchial epithelium. We studied the expression and regulation of SPR1 in a series of human bronchial epithelial cell lines representing a model of multistep bronchial carcinogenesis. These cell lines included a primary culture of tracheobronchial epithelial cells (HTBE), a papilloma virus-transformed tracheobronchial epithelial cell line (HBE1), a cell line selected from HBE1 by a tobacco carcinogen and a phorbol ester (HBE1-C), a simian virus-transformed bronchial epithelial cell line (BEAS-2B), and a lung carcinoma cell line (H460). Different tumorigenic potentials of these cell lines were indicated by graded levels of telomerase activity. Concomitant with squamous transformation, there was an increase in SPR1 expression in HTBE, HBE1, and HBE1-C that was reversible by vitamin A. With progression of tumorigenicity, there was a marked reduction in SPR1 expression in BEAS-2B and a total loss of expression in H460. In these latter cell lines representing advanced malignant transformation, there was a loss of up- and downregulation, respectively, by the phorbol ester and vitamin A. Transfection study with chimeric constructs of the SPR1 promoter and a reporter gene showed that the dysregulation of SPR1 expression in malignant transformation was a result of perturbation of the basal and enhancer elements of the first 162 nucleotides in the 5'-flanking promoter region of the SPR1 gene. These findings suggest an association of transcriptional dysregulation of the SPR1 gene with multistep bronchial carcinogenesis.

Using 12 microsatellite markers, we have studied DNAs from the bronchial lavage of 90 individuals who were referred to an early-lung-cancer clinic in the Northwest of England with suspected lung cancer. Genetic alterations were detected in 15 (35%) of 43 patients with lung cancer but also in 11 (23%) of 47 patients with no cytological or radiological evidence of bronchial neoplasia. No significant differences were found between the referring symptoms in any of the second group of individuals with and without genetic alterations. No correlation was found between smoking exposure and loss of heterozygosity (LOH)/microsatellite alterations (MAs) in the microsatellite markers. On comparing LOH with MAs based on cytology review, we found that the prevalent type of alteration in specimens with cytological evidence of malignancy was LOH; in contrast, the individuals with no cytological evidence of malignancy showed a preponderance of MAs (P = 0.01). Our results indicate that a substantial proportion of cells in the bronchial lavage from suspected lung cancer patients carry identifiable genetic alterations. However, the presence of genetic alterations in the bronchial lavage of individuals with no clinical evidence of lung cancer raises the question whether instability is a phenomenon solely associated with cancer or represents a feature of nonneoplastic diseases. Our results suggest that microsatellite PCR-based assays can be developed as tools for the earlier identification of genetic changes in cells exfoliating in the bronchus.