Histopathologic Changes in Congenital Corneal Stromal Dystrophy: Report of 4 Cases in 2 Families.

Corneal dystrophies are hereditary diseases affecting the corneal tissue; they are bilateral, symmetrical and unrelated to environmental or systemic conditions. Congenital corneal stromal dystrophy is a very rare autosomal dominant dystrophy that is caused by a mutation in the DCN gene that encodes decorin (a proteoglycan of the extracellular matrix). We herein report 4 cases of congenital stromal corneal dystrophy in 2 families, highlighting the previously undescribed histopathologic features, the possible differential diagnosis of this entity and the key role played by decorin staining in its diagnosis.

Analysis of the Effects of Melanin Depigmentation on Immunohistochemical Staining.

Heavily pigmented lesions are difficult to evaluate histologically, as melanin obscures cellular details. Several classic laboratory techniques aim to clear melanin and allow evaluation. Most of them are old and appeared before immunohistochemistry (IHC) use. Many laboratories perform IHC with aminoethylcarbazole instead of diaminobenzidine (DAB) in heavily pigmented lesions, as red-stained is easy to interpret despite pigmentation. Nevertheless, many laboratories lack alternatives to DAB. The aim of this study is to compare 6 different tissue bleaching techniques and evaluate which is the best for immunohistochemical staining with DAB. In the present study we have selected a case with gross pigmentation because of the high grade of melanin deposition. We have performed 6 different bleaching techniques and subsequently performed 2 different IHC stains, frequently used in melanoma: SOX10 (nuclear) and Melan-A (cytoplasmic). Five different pathologists, 2 of them with expertise in dermatopathology, have blindly reviewed and scored the staining quality. Our results indicate a high grade of interobserver concordance in the evaluation of IHC results between pathologists. All the bleaching techniques that included a sulfuric acid led to tissue detachment from the slide. The best method for SOX10 was that based in potassium permanganate, with a high quality of staining (4 over 5), while the best method for Melan-A was the 1 based in peroxide hydrogen (4 over 5). We consider this study can be quite useful for those laboratories lacking aminoethylcarbazole for IHC techniques, allowing the use of DAB for IHC of heavily pigmented lesions.

Akkermansia deficiency and mucin depletion are implicated in intestinal barrier dysfunction as earlier event in the development of inflammation in interleukin-10-deficient mice.

Background: Dysbiosis and mucin depletion are related with intestinal barrier dysfunction and seems to be an early pathophysiological event in inflammatory bowel disease (IBD). The objective of this work is to study these parameters in the natural history of colitis in IL-10 deficient mice (IL-10-/-). Methods: Wild type (WT) and IL-10-/-. mice were followed until sacrifice at 3, 5, 10, 20, 57, and 70 weeks. Body weight, colonic weight/length ratio and in vivo intestinal permeability were registered. Expression of inflammatory and adhesion molecules in the colon was explored by qPCR as Mucin-2 (MUC-2) and molecules involved in goblet cell maturation Interleukin-18 (IL-18) and WAP Four-Disulfide Core Domain 2 (WFDC2), the endoplasmic reticulum stress markers X-box-binding protein (Xbp-1) and Reticulon-4B (RTN-4B). Bacterial composition in feces and colonic mucosa was determined by massive sequencing of the V3-V4 regions of 16S rDNA gene. Results: IL-10-/- mice showed histological inflammation at weeks 20 and 57, but most notably the intestinal permeability was significantly higher from week 10. Concordantly, the number of goblet cells and expression of MUC-2, IL-18, WFDC2 and Xbp-1 were significantly lower in KO from week 10. Nevertheless, no significant differences were found in the mRNA expression of MUC-2 or Xbp-1 between both groups-derived colon organoids. Significant bacterial differences began at week 5, being the Akkermansia deficiency in KO the most relevant result. Conclusion: Gut microbiota alterations and mucin depletion are associated with early intestinal barrier dysfunction and precede overt gut inflammation in this animal model of IBD.

ΔNp73, TAp73 and Δ133p53 Extracellular Vesicle Cargo as Early Diagnosis Markers in Colorectal Cancer.

The early diagnosis of colorectal cancer is a key factor in the overall survival of the patients. The actual screening programs include different approaches with significant limitations such as unspecificity, high invasiveness, and detection at late stages of the disease. The specific content of extracellular vesicles derived from malignant cells may represent a non-invasive technique for the early detection of colorectal cancer. Here, we studied the mRNA levels of ΔNp73, TAp73, and Δ133p53 in plasma-derived extracellular vesicles from healthy subjects (n = 29), individuals with premalignant lesions (n = 49), and colorectal cancer patients (n = 42). Extracellular vesicles' ΔNp73 levels were already significantly high in subjects with premalignant lesions. Δ133p53 levels were statistically increased in colorectal cancer patients compared to the other two groups and were associated with patients' survival. Remarkably, TAp73 mRNA was not detected in any of the individuals. The evaluation of ΔNp73, Δ133p53 and CEA sensitivity, specificity and AUC values supports ΔNp73 as a better early diagnosis biomarker and CEA as the best to identify advanced stages. Thus, low levels of CEA and a high content of ΔNp73 may identify in screening programs those individuals at higher risk of presenting a premalignant lesion. In addition, Δ133p53 emerges as a potential prognosis biomarker in colorectal cancer.

The Clinical Significance of PIWIL3 and PIWIL4 Expression in Pancreatic Cancer.

P-element-induced wimpy testis (PIWI) proteins have been described in several cancers. PIWIL1 and PIWIL2 have been recently evaluated in pancreatic cancer, and elevated expression of PIWIL2 conferred longer survival to patients. However, PIWIL3's and PIWIL4's role in carcinogenesis is rather controversial, and their clinical implication in pancreatic cancer has not yet been investigated. In the present study, we evaluated PIWIL1, PIWIL2, PIWIL3 and PIWIL4 expression in pancreatic cancer-derived cell lines and in one non-tumor cell line as healthy control. Here, we show a differential expression in tumor and non-tumor cell lines of PIWIL3 and PIWIL4. Subsequently, functional experiments with PIWIL3 and/or PIWIL4 knockdown revealed a decrease in the motility ratio of tumor and non-tumor cell lines through downregulation of mesenchymal factors in pro of epithelial factors. We also observed that PIWIL3 and/or PIWIL4 silencing impaired undifferentiated phenotype and enhanced drug toxicity in both tumor- and non-tumor-derived cell lines. Finally, PIWIL3 and PIWIL4 evaluation in human pancreatic cancer samples showed that patients with low levels of PIWIL4 protein expression presented poor prognosis. Therefore, PIWIL3 and PIWIL4 proteins may play crucial roles to keep pancreatic cell homeostasis not only in tumors but also in healthy tissues.

The Prognosis Value of PIWIL1 and PIWIL2 Expression in Pancreatic Cancer.

Pancreatic cancer is a highly aggressive manifestation of cancer, and currently presents poor clinical outcome due to its late diagnosis with metastasic disease. Surgery is the only approach with a curative intend; however, the survival rates seen in this type of patient are still low. After surgery, there is a lack of predictive prognosis biomarkers to predict treatment response and survival to establish a personalized medicine. Human P-element-induced wimpy testis 1 (PIWIL1) and P-element-induced wimpy testis 2 (PIWIL2) proteins act as protectors of germline, and their aberrant expression has been described in several types of tumors. In this study, we aimed to assess an association between PIWIL1 and PIWIL2 expression and the prognosis of biliopancreatic cancer patients. For this, we analyzed protein expression in complete resected tumor samples, and found a significant association between PIWIL2 expression and both progression-free and overall survival (p = 0.036 and p = 0.012, respectively). However, PIWIL2 expression was significantly associated with progression-free survival (p = 0.029), and overall survival (p = 0.025) of such tumors originated in the pancreas, but not in the bile duct or ampulla of Vater. Further analysis revealed that PIWIL1 and PIWIL2, at both mRNA and protein expression levels, correlated positively with factors associated to the progenitor molecular subtype of pancreatic cancer. Based on these findings, PIWIL1 and PIWIL2 expression may be considered a potential prognostic biomarker for resectable pancreatic cancer and may serve to guide subsequent adjuvant treatment decisions.

UNR/CSDE1 Expression Is Critical to Maintain Invasive Phenotype of Colorectal Cancer through Regulation of c-MYC and Epithelial-to-Mesenchymal Transition.

CSDE1 (cold shock domain containing E1) gene is located upstream of the N-RAS locus, and codes for an RNA-binding protein named Upstream of N-Ras (UNR). In cancer, CSDE1 has been shown to regulate c-Fos, c-Myc, Pten, Rac1, or Vimentin. UNR/CSDE1 has been studied in breast, melanoma, pancreatic and prostate cancer. Then, the aim of this study is to evaluate the role of CSDE1/UNR in colorectal cancer progression and maintenance of aggressive phenotype. We firstly evaluated UNR/CSDE1 expression in human colon cancer derived cell lines and patient samples. Subsequently, we performed functional experiments by UNR/CSDE1 downregulation. We also evaluated UNR/CSDE1 prognostic relevance in two independent sets of patients. Not only was UNR/CSDE1 expression higher in tumor samples compared to untransformed samples, but also in colonospheres and metastatic origin cell lines than their parental and primary cell lines, respectively. Downregulation of UNR/CSDE1 reduced cell viability and migration throughout a restrain of epithelial-to-mesenchymal transition and increases sensitivity to apoptosis. Interestingly, high UNR/CSDE1 expression was associated with poor prognosis and correlated positively with c-MYC expression in colorectal cancer samples and cell lines. Here, we show for the first time compelling data reporting the oncogenic role of UNR/CSDE1 in human colorectal cancer.

Clinical Implications of NRAS Overexpression in Resectable Pancreatic Adenocarcinoma Patients.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal forms of cancer, and its incidence is rising worldwide. Although survival can be improved by surgical resection, when detected at an early stage, this type of cancer is usually asymptomatic, and disease becomes only apparent after metastasis. Adjuvant treatment does not improve survival, thus after surgery there is a lack of predictive and prognosis biomarkers to predict treatment response and survival. The mitogen-activated protein-kinase and phosphoinositide 3-kinase signalling pathways play a crucial role in cancer development and progression. Especially, activated RAS proteins promote cell proliferation through constitutive stimulation of the downstream effectors RAF-MEK-ERK and PI3K-AKT. Mutational status of NRAS is required in several types of cancer like colorectal or cutaneous melanoma. However, mutations in this gene are very scarce in PDAC patients, and NRAS determination is not usually performed in clinical practice for this kind of tumor. In this study, we analyse the association between NRAS protein expression and progression-free survival and overall survival of an homogenous cohort of pancreatic ductal adenocarcinoma patients from a single-centre. Interestingly, we found that patients with high expression not only showed longer progression-free survival than those patients with low expression (22 versus 9 months, respectively) (P = 0.013), but also longer overall survival (43 versus 19 months, respectively) (P = 0.020). These results confirm NRAS expression could be used to differentiate patients according to their prognosis. Proportional hazard model revealed NRAS expression together with grade of differentiation as pathological variables to predict patient's outcome.

Fibrin patch influences the expression of hypoxia-inducible factor-1α and nuclear factor-κBp65 factors on ischemic intestinal anastomosis.

The intestinal anastomotic failure is one of the most severe complications in gastrointestinal surgery. Despite the great surgical improvements during the last decade, anastomotic leak rates remain practically the same, with a dramatically high grade of morbidity for patients. Leakages are usually the final consequence of ischemia in the anastomosis, leading to tissue hypoxia. In response to hypoxia, the cell orchestrates a variety of coordinated responses in order to restore oxygen homeostasis. The molecular mechanism of hypoxia sensitivity involves oxygen sensing hydroxylases, prolyl-hydroxylases, orchestrating two main transcription factors related to induction of inflammation and angiogenesis, namely nuclear factor-κB and hypoxia-inducible factors. The immunohistochemical expression of two transcription factors hypoxia-inducible factors-1α and nuclear factor-κB p65 has already been described in several disorders, including wound healing, asthma and chronic obstructive lung disease, rheumatoid arthritis, cancer, inflammatory bowel disease, and acute colitis. In the surgical field, fibrin sealants have been widely used to prevent leaks in lung surgery and they might also be useful as a reinforcement of sutures in intestinal anastomosis. The commercial fibrin sealant patches are hemostatic and adhesive surgical agents mainly derived from human plasma. We herein report the results of a prospective randomized experimental study on pigs. We performed a high-risk leakage model of bowel anastomosis, causing a significant devascularization of 10-15 cm of the bowel wall before performing a conventional colo-ileal anastomosis. We randomized the animals to receive a covering of the anastomosis with a fibrin patch (case group) or not (control group). We report the changes in the immunohistochemical expression of the proteins involved in tissue response to hypoxia in the experimental model. Our results indicate that the fibrin patch delays the healing response, promoting a longer lasting inflammation in the surgical bed. Nevertheless, the fibrin patches effectiveness to reduce dehiscence shown in clinical practice suggests that this delay does not negatively affect patients' outcome. Impact statement The consequences of the anastomotic failure are dramatic for patients. Understanding how the ever-increasing use of fibrin sealant, that seems to have a beneficial effect on the anastomoses, interacts with the tissue and the healing process can help to justify its use and encourage research on how to improve this effect even more. We feel that the present work shows that the patch can improve healing by complex mechanisms other than the mere contention and physical support of the intestine. Furthermore, research is needed to confirm our preliminary findings.

Tumor-associated macrophages (TAMs) depend on ZEB1 for their cancer-promoting roles.

Accumulation of tumor-associated macrophages (TAMs) associates with malignant progression in cancer. However, the mechanisms that drive the pro-tumor functions of TAMs are not fully understood. ZEB1 is best known for driving an epithelial-to-mesenchymal transition (EMT) in cancer cells to promote tumor progression. However, a role for ZEB1 in macrophages and TAMs has not been studied. Here we describe that TAMs require ZEB1 for their tumor-promoting and chemotherapy resistance functions in a mouse model of ovarian cancer. Only TAMs that expressed full levels of Zeb1 accelerated tumor growth. Mechanistically, ZEB1 expression in TAMs induced their polarization toward an F4/80low pro-tumor phenotype, including direct activation of Ccr2 In turn, expression of ZEB1 by TAMs induced Ccl2, Cd74, and a mesenchymal/stem-like phenotype in cancer cells. In human ovarian carcinomas, TAM infiltration and CCR2 expression correlated with ZEB1 in tumor cells, where along with CCL2 and CD74 determined poorer prognosis. Importantly, ZEB1 in TAMs was a factor of poorer survival in human ovarian carcinomas. These data establish ZEB1 as a key factor in the tumor microenvironment and for maintaining TAMs' tumor-promoting functions.

MicroRNA-21 predicts response to preoperative chemoradiotherapy in locally advanced rectal cancer.

PURPOSE: The treatment of choice for locally advanced rectal cancer is preoperative chemoradiotherapy. Despite half of patients do not respond and suffer unnecessary toxicities and surgery delays, there are no biomarkers to guide preoperative CRT outcome. MicroRNA-21 has been related to acquisition of 5-fluorouracil resistance; however, its potential predictive value of response to preoperative chemoradiotherapy in locally advanced rectal cancer remains unknown. METHODS: Nighty-two patients diagnosed with locally advanced rectal cancer who were preoperatively treated with chemoradiotherapy were selected for this study. Moreover, microRNA-21 expression was quantified in formalin-fixed paraffin-embedded biopsies from this cohort, and the results obtained were correlated with clinical and molecular characteristics, pathological response, and outcome. RESULTS: MicroRNA-21 was found overexpressed in 77.6% cases, and significantly correlated with tumor grade after preoperative chemoradiotherapy (P = 0.013) and with pathological response (P = 0.013). The odds ratio of having miR-21 overexpression and not getting a respond to chemoradiotherapy resulted in 9.75 CI 2.24 to 42. Sensitivity, specificity, negative predictive values, and positive predictive value were 86.6, 60, 42.8, and 92%, respectively. Multivariate analysis confirmed the clinical significance of miR-21 determining preoperative chemoradiotherapy response. CONCLUSIONS: MicroRNA-21 expression efficiently predicts preoperative chemoradiotherapy pathological response in locally advanced rectal cancer.

Sperm protein 17 and AKAP-associated sperm protein cancer/testis antigens are expressed in ciliated hepatic foregut cysts.

AIMS: Ciliated hepatic foregut cysts (CHFCs) are retained benign lesions of the liver. However, a case of squamous cell metaplasia and five cases of squamous cell carcinoma arising from a CHFC have been described. The potential of malignant transformation makes the identification of new biomarkers necessary. As the cancer/testis antigen sperm protein 17 (Sp17) has been detected in oral and oesophageal squamous cell carcinomas, the aim of this study was to investigate the expression of Sp17 and AKAP-associated sperm protein (ASP), which has a shared N-terminal sequence with Sp17, in four surgically resected CHFCs. METHODS AND RESULTS: CHFC specimens were taken from two patients who attended the Medical College of Wisconsin, Milwaukee, USA and two patients who attended the Fundación Jiménez Díaz, Madrid, Spain. CHFCs were found to be immunopositive for Sp17 and ASP. Both proteins were localized to the cytoplasm of ciliated cells lining the cysts, and their cilia. Confocal microscopy demonstrated that Sp17 and ASP overlapped in the same region of the cell. CONCLUSION: Sp17 and ASP cancer/testis antigens were found in ciliated cells of four CHFCs. Further characterization of Sp17 and ASP in patients with CHFCs may provide significant clues for understanding the molecular mechanisms underlying their predisposition to develop squamous cell carcinomas.

Metastatic melanoma in association with a giant congenital melanocytic nevus in an adult: controversial CGH findings.

Giant congenital melanocytic nevi (GCMNs) represent a distress to patients for 2 reasons: one is disfigurement, and the other is the increased risk of developing secondary melanocytic tumors, such as benign proliferative nodules (BPNs) and malignant melanoma (MM). BPN present as a rapid growth nodule arising within a congenital melanocytic nevus (CMN) that often ulcerates, occurs in children younger than 2 years of age. BPNs arising within a CMN are exceedingly rare after childhood, and very few cases have been described in adults. Despite the worrisome clinical and histologic findings of BPN, most laboratory investigations seem to support their benignity. The distinction between MM and BPN is extremely important, but the histopathology of BPN of GCMN can be a challenge to differentiate from MM. In the recent years, molecular tests that investigate DNA copy number alterations such as fluorescence in situ hybridization and comparative genomic hybridization have shown promise to help guide the diagnosis of ambiguous melanocytic proliferations arising within CMNs. We report the case of a 22-year-old woman with a nodule arising in a GCMN and with an axillary mass suggesting a nodal metastasis of melanoma, and discuss the unusual clinical, histopathologic, and molecular findings that make this case particularly interesting.

DEK is a potential marker for aggressive phenotype and irinotecan-based therapy response in metastatic colorectal cancer.

BACKGROUND: DEK is a transcription factor involved in stabilization of heterochromatin and cruciform structures. It plays an important role in development and progression of different types of cancer. This study aims to analyze the role of DEK in metastatic colorectal cancer. METHODS: Baseline DEK expression was firstly quantified in 9 colorectal cell lines and normal mucosa by WB. SiRNA-mediated DEK inhibition was carried out for transient DEK silencing in DLD1 and SW620 to dissect its role in colorectal cancer aggressiveness. Irinotecan response assays were performed with SN38 over 24 hours and apoptosis was quantified by flow cytometry. Ex-vivo assay was carried out with 3 fresh tumour tissues taken from surgical resection and treated with SN38 for 24 hours. DEK expression was determined by immunohistochemistry in 67 formalin-fixed paraffin-embedded tumour samples from metastatic colorectal cancer patients treated with irinotecan-based therapy as first-line treatment. RESULTS: The DEK oncogene is overexpressed in all colorectal cancer cell lines. Knock-down of DEK on DLD1 and SW620 cell lines decreased cell migration and increased irinotecan-induced apoptosis. In addition, low DEK expression level predicted irinotecan-based chemotherapy response in metastatic colorectal cancer patients with KRAS wild-type. CONCLUSIONS: These data suggest DEK overexpression as a crucial event for the emergence of an aggressive phenotype in colorectal cancer and its potential role as biomarker for irinotecan response in those patients with KRAS wild-type status.

Snail1 expression is required for sarcomagenesis.

Snail1 transcriptional repressor is a major inducer of epithelial-to mesenchymal transition but is very limitedly expressed in adult animals. We have previously demonstrated that Snail1 is required for the maintenance of mesenchymal stem cells (MSCs), preventing their premature differentiation. Now, we show that Snail1 controls the tumorigenic properties of mesenchymal cells. Increased Snail1 expression provides tumorigenic capabilities to fibroblastic cells; on the contrary, Snail1 depletion decreases tumor growth. Genetic depletion of Snail1 in MSCs that are deficient in p53 tumor suppressor downregulates MSC markers and prevents the capability of these cells to originate sarcomas in immunodeficient SCID mice. Notably, an analysis of human sarcomas shows that, contrarily to epithelial tumors, these neoplasms display high Snail1 expression. This is particularly clear for undifferentiated tumors, which are associated with poor outcome. Together, our results indicate a role for Snail1 in the generation of sarcomas.

Stage pT3a of renal clear cell carcinoma: do tumors with sinus fat involvement behave the same as those with perinephric fat involvement?

INTRODUCTION: In this report, we review our series of patients with pT3a clear cell renal carcinoma (CCRC) and comment on their outcome. MATERIALS AND METHODS: We have reviewed 260 cases of CCRC operated in the Móstoles General Hospital, Madrid, between 2000 and 2004. We have found 30 cases with pT3a tumors. Eleven of them were invading the perinephric fat, nine were invading the renal sinus fat and ten were pT3a locally but showed metastasis at the moment of diagnosis (cM1, TNM stage IV). We have analyzed the prognostic influence of histopathological parameters (vascular invasion, size, Fuhrman grade) and also immunohistochemical ones (p53, cyclin D1, proliferation index with Ki67, bcl-2 and vascular density with CD34). RESULTS: Only six of 10 patients with perinephric fat involvement died of disease compared with all the patients with sinus fat involvement, suggesting a worse prognosis for the latter. However, this difference did not reach statistical significance, probably due to the small number of cases. Of all the clinical, histological and immunohistochemical factors analyzed, only cyclin D1 was a strong indicator of worse prognosis in pT3a CCRC (p=0.02). We could not show any statistically significant relation between vascular density and prognosis. Vascular invasion was the only histological parameter that showed a trend toward significance (p=0.09). CONCLUSIONS: Sinus fat involvement might be underestimated in some series. A protocol for nephrectomy specimen handling could improve the detection rate of sinus fat involvement and allow the performance of randomized prospective studies to determine whether these tumors behave similarly.

Aberrant TTF-1 expression in papillary high-grade urothelial neoplasm: case report and literature review.

We herein report the case of a 48-year-old man who developed synchronous advanced tumors in the lung and the bladder. The most striking feature of our case is that the otherwise typical bladder urothelial carcinoma showed focal areas (comprising less than 5% of the tumor mass) of nuclear positivity for TTF-1 (thyroid transcription factor-1). The different pattern of cytokeratin expression led us to consider them two independent primary tumors. Several recent reports have indicated that the type of clone used can influence the results of TTF-1 staining and can explain positivity in extrapulmonary and extrathyroid tumors.

Solitary angiokeratoma of the tongue in adults.

Angiokeratomas are vascular malformations that usually appear as multiple or solitary cutaneous plaques. Several clinical variants have been described, with the same underlying histopathological lesion. Mucosal involvement, including the oral cavity, is occasionally found either as a component of the systemic variety, called angiokeratoma corporis diffusum, or associated with cutaneous lesions in more locations. Isolated oral involvement seems to be rather infrequent and only five cases have been described in adults in the world literature. We herein report another case of this rare entity affecting a 62-year-old woman in the dorsum at the tip of the tongue. This is the first report including an immunohistochemical study to discard a lymphatic origin of the tumor.

Tumor necrosis factor alpha as a marker of systemic and local inflammation in "healthy" smokers.

BACKGROUND: Tobacco smoking induces a local and systemic inflammatory reaction and also a decline in pulmonary function. There are some novel noninvasive methods to measure the degree of inflammatory bronchial reaction, including the exhaled breath condensate (EBC) in which several inflammatory markers can be measured, including tumor necrosis factor alpha (TNF-alpha). There is a clear clinical need to develop methods that allow early detection of smokers at risk of losing pulmonary function. OBJECTIVES: THE AIMS OF THE PRESENT STUDY ARE: 1) to show that smokers show higher levels of TNF-alpha both in serum and EBC; 2) to analyze the possible influence of gender, age, and weight on this parameter; and 3) to determine a possible association between smoking and pulmonary function parameters and TNF-alpha levels. MATERIAL AND METHODS: We have prospectively analyzed two cohorts of smokers and non-smokers subjects without any chronic or acute disease (within eight weeks of study initiation). We have performed pulmonary function tests with bronchodilators and also collected EBC and blood samples before smoking cessation. Statistical analysis was performed with SPSS 11.0 for Windows Statistical Package. RESULTS: The study has enrolled 17 patients (8 smokers), 50% of whom were females. Mean age was 38.59 years old (standard deviation, 7.4). The mean number of cigarettes smoked in the smoker group was 26.14 (11.29) cigarettes/day and the mean age when tobacco first began was 15.14 (2.04) years. We have not been able to show any significant differences in TNF-alpha levels according to age or weight. For the whole series we have not found any significant influence of gender in TNF-alpha levels, but after dividing the series in smokers and nonsmokers, we have shown higher levels of TNF-alpha in serum (5.59 [0.26] pg/mL vs 5.56 [0.37] pg/mL; nonsignificant [NS]) and EBC (4.94 [0.41] pg/mL vs 4.22 [0.36] pg/mL; p = 0.031) in male smokers. On the other hand, nonsmoking females showed slightly higher TNF-alpha levels in serum (5.70 [0.50] pg/mL vs 5.42 [0.29] pg/mL; NS) and EBC (4.54 [0.92] vs 4.11 [0.41 pg/mL]; NS). Smokers had higher TNF-alpha levels in EBC (4.46 [0.58] pg/mL vs 4.34 [0.62] pg/mL; NS), while serum TNF-alpha levels were slightly higher in nonsmokers (5.52 [0.56] pg/mL vs 5.50 [0.27] pg/mL; NS). We have not demonstrated any association between tobacco consumption and TNF-alpha levels. We have not shown any significant relation between pulmonary function and the studied parameters, with only a modest association between forced expiratory volume at one second and forced vital capacity and TNF-alpha levels in EBC. CONCLUSION: Smokers show higher TNF-alpha levels in EBC. Among smokers, males show higher levels of TNF in serum and EBC. We have not confirmed any significant influence of age or weight on TNF-alpha levels. These levels do not seem to be influenced either by the amount of tobacco or the time since habit began. We have shown a modest relation between pulmonary function and TNF-alpha levels in EBC.