Alejandro Avilés-Salas

Diagnosis of EML4-ALK Translocation With FISH, Immunohistochemistry, and Real-time Polymerase Chain Reaction in Patients With Non-Small Cell Lung Cancer.

Objective: To assess anaplastic lymphoma kinase (ALK) rearrangement detection with immunohistochemistry (IHC) and real-time polymerase chain reaction (RT-qPCR) in comparison with fluorescence in situ hybridization (FISH). Methods: Tumor tissue samples from 230 patients with advanced non–small cell lung cancer (NSCLC) were analyzed by FISH to detect ALK rearrangements. Additional IHC tests using 5A4 clone and RT-qPCR (variants 1 to 5) were performed in 63 and 48 patients, respectively. Results: Thirteen percent of FISH tests were not evaluable. From the remaining tests (n=200), 18 (9.0%) were ALK positive (ALK+). ALK+ patients were significantly younger at the time of diagnosis (below 55 y, 14.3% vs. 5.5%, P=0.035), were light smokers (tobacco index <10, 12.6% vs. 4.1%, P=0.049), and presented adenocarcinoma with a mucinous component (30.8 vs. 8.0%, P=0.007). When comparing FISH with IHC using a cutoff of 1+ or 2+, and only 2+ staining intensity, the sensitivity, specificity, negative predictive value, and positive predictive value were as follows: 83.3%, 100.0%, 93.75%, and 100.0%; and 55.6%, 100.0%, 84.9%, and 100.0%, respectively. For RT-qPCR, these results were 55.6, 100, 90.7, and 100.0%, respectively. Conclusions: Our results suggest that RT-qPCR is an inadequate initial test for detecting ALK-positive lung cancer. IHC is highly useful as an initial screening test for ALK rearrangement detection in NSCLC. These results contribute to the medical literature on the establishment of IHC as a standard diagnostic test for ALK rearrangements in NSCLC.

P38 MAPK expression and activation predicts failure of response to CHOP in patients with Diffuse Large B-Cell Lymphoma

BackgroundThe p38 MAPK is constitutively activated in B-NHL cell lines and regulates chemoresistance. Accordingly, we hypothesized that activated p38 MAPK may be associated with the in vivo unresponsiveness to chemotherapy in B-NHL patients.MethodsTissue microarrays generated from eighty untreated patients with Diffused Large B Cell Lymphoma (DLBCL) were examined by immunohistochemistry for the expression of p38 and phospho p38 (p-p38) MAPK. In addition, both Bcl-2 and NF-κB expressions were determined. Kaplan Meier analysis was assessed.ResultsTumor tissues expressed p38 MAPK (82xa0%) and p-p38 MAPK (30xa0%). Both p38 and p-p38 MAPK expressions correlated with the high score performance status. A significant correlation was found between the expression p-p38 and poor response to CHOP. The five year median follow-up FFS was 81xa0% for p38− and 34xa0% for p38+ and for OS was 83xa0% for p38− and 47xa0% for p38+. The p-p38+ tissues expressed Bcl-2 and 90xa0% of p-p38− where Bcl-2−. The coexpression of p-p38 and Bcl-2 correlated with pool EFS and OS. There was no correlation between the expression of p-p38 and the expression of NF-κB.ConclusionThe findings revealed, for the first time, that a subset of patients with DLBCL and whose tumors expressed high p-p38 MAPK responded poorly to CHOP therapy and had poor EFS and OS. The expression of p38, p-p38, Bcl2 and the ABC subtype are significant risk factors both p38 and p-p38 expressions remain independent prognostic factors.

Gene-expression profiles in lung adenocarcinomas related to chronic wood smoke or tobacco exposure

BackgroundTobacco-smoke is the major etiological factor related to lung cancer. However, other important factor is chronic wood smoke exposure (WSE). Approximately 30xa0% of lung cancer patients in Mexico have a history of WSE, and present different clinical, pathological and molecular characteristics compared to tobacco related lung cancer, including differences in mutational profiles. There are several molecular alterations identified in WSE associated lung cancer, however most studies have focused on the analysis of changes in several pathogenesis related proteins.MethodsOur group evaluated gene expression profiles of primary lung adenocarcinoma, from patients with history of WSE or tobacco exposure. Differential expression between these two groups were studied through gene expression microarrays.ResultsResults of the gene expression profiling revealed 57 statistically significant genes (pu2009<u20090.01). The associated biological functional pathways included: lipid metabolism, biochemistry of small molecules, molecular transport, cell morphology, function and maintenance. A highlight of our analysis is that three of the main functional networks represent 37 differentially expressed genes out of the 57 found. These hubs are related with ubiquitin C, GABA(A) receptor-associated like protein; and the PI3K/AKT and MEK/ERK signaling pathways.ConclusionOur results reflect the intrinsic biology that sustains the development of adenocarcinoma related to WSE and show that there is a different gene expression profile of WSE associated lung adenocarcinoma compared to tobacco exposure, suggesting that they arise through different carcinogenic mechanisms, which may explain the clinical and mutation profile divergences between both lung adenocarcinomas.

Differential gene expression profiles according to the Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society histopathological classification in lung adenocarcinoma subtypes

The current lung cancer classification from the Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society has considerably changed the pathologic diagnosis of lung invasive adenocarcinoma, identifying disease subtypes with substantial implications for medical practice, such as clinical, radiological, molecular, and prognostic differences. We analyzed the differences in the genetic expression of adenocarcinoma subtypes according to the new classification. Microarray gene expression analysis was performed on a cohort of 29 adenocarcinoma patients treated at the Instituto Nacional de Cancerología of Mexico from 2008 to 2011. All patients had an available biopsy sample and were classified into 4 different subtypes of adenocarcinoma (2015 World Health Organization classification). Lepidic-predominant adenocarcinoma was the only pattern that exhibited a marked gene expression difference compared with other predominant histologic patterns, revealing genes with significant expression (P < .01). Moreover, we identified 13 genes with specific differential expression in the lepidic-predominant adenocarcinoma that could be used as a gene signature. The lepidic-predominant histologic pattern has a differential gene expression profile compared with all predominant histologic patterns. Additionally, we identified a gene expression signature of 13 genes that have a unique behavior in the lepidic histologic pattern; these 13 genes are candidates for follow-up studies for their potential use as biomarkers or therapeutic targets. Results from this study highlight the importance of the new Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society classification and exemplify the potential clinical implications of correlating histopathology with exclusive molecular beacons.

Reproducibility of the EGFR immunohistochemistry scores for tumor samples from patients with advanced non-small cell lung cancer

Epidermal growth factor receptor (EGFR) is overexpressed in >60% of non-small cell lung cancer (NSCLC) cases. In combination with radiotherapy or chemotherapy, first-line treatments with antibodies against EGFR, including cetuximab and necitumumab, have demonstrated benefits by increasing overall survival (OS), particularly in patients who overexpress EGFR. The present study evaluated the interobserver agreement among three senior pathologists, who were blinded to the clinical outcomes and assessed tumor samples from 85 patients with NSCLC using the H-score method. EGFR immunohistochemistry was performed using a qualitative immunohistochemical kit. The reported (mean ± standard deviation) H-scores from each pathologist were 111±102, 127±103 and 128.53±104.03. The patients with average H-scores ≥1, ≥100, ≥200 and between 250-300 were 85.9, 54.1, 28.2 and 12.9, respectively. Patients who had an average H-score >100 had a shorter OS time compared with those with lower scores. Furthermore, patients with EGFR mutations who were treated with EGFR-tyrosine kinase inhibitors (TKIs) and had an average H-score >100 had a longer OS time compared with those with an average H-score <100. The interobserver concordance for the total H-scores were 0.982, 0.980 and 0.988, and for a positive H-score ≥200, the interobserver concordance was 0.773, 0.710 and 0.675, respectively. The determination of EGFR expression by the H-score method is highly reproducible among pathologists and is a prognostic factor associated with a poor OS in all patients. Additionally, the results of the present study suggest that patients with EGFR mutations that are treated with EGFR-TKIs and present with a high H-score have a longer OS time.

Association between nuclear expression of retinoic acid receptor alpha and beta and clinicopathological features and prognosis of advanced non-small cell lung cancer

BackgroundTranscription factors such as retinoic acid receptor alpha (RARα) and beta (RARβ) and Yin Yang 1 (YY1) are associated with the progression of non-small cell lung cancer (NSCLC). In particular, a lack of RARβ expression is associated with NSCLC development. The aim of this study was to analyze the expression of RARα, RARβ and YY1 and their relationship with prognosis in patients with advanced NSCLC.MethodsThe expression of RARα, RARβ and YY1 was assessed by immunohistochemistry and quantitative computerized image software.ResultsEighty-five patients treated with platinum-based chemotherapy were included in the analysis. The mean and standard deviation of the nuclear expression of RARα, RARβ and YY1 were 184.5xa0±xa0124.4, 18xa0±xa027 and 16.6xa0±xa020.5, respectively. The nuclear expression of RARβ was associated with the nuclear expression of YY1 (R2xa0=xa00.28; p valuexa0<xa00.0001). Patients with high nuclear expression of YY1 were likely to be non-smokers (61.9 vs 40.5xa0%). Median progression-free survival (PFS) was 5.9xa0months (3.48–8.28). Low expression of RARα was independently associated with worse PFS following chemotherapy (10.3 vs 5.46xa0months pxa0=xa00.040). Median overall survival (OS) was 15.6xa0months (4.5–26.7), and lower nuclear expression of RARβ was independently associated with shorter OS (27.5 vs 8.7xa0months; pxa0=xa00.037).ConclusionOur study suggests that the loss of RARs is associated with a worse prognosis and these receptors could be a potential molecular target for NSCLC.

Targeted next generation sequencing identified a high frequency genetic mutated profile in wood smoke exposure-related lung adenocarcinoma patients

Background Wood smoke exposure (WSE) has been associated with an increased risk of lung cancer development. WSE has been related with high frequency of EGFR mutations and low frequency of KRAS mutations. The aim of this study was to evaluate large scale genomic alterations in lung adenocarcinomas associated with WSE using targeted next generation sequencing. Methods DNA multi-targeted sequencing was performed in 42 fresh-frozen samples of advanced lung adenocarcinomas. The TruSeQ Cancer Panel (Illumina) was used for genomic library construction and sequencing assays. Results WSE rate was higher in women (p=0.037) and non-smokers (p=0.001). WSE correlated with mutations in the genes SMARCB1 (p=0.002), Ataxia telangiectasia mutated (p=0.004), Kinase Insert Domain Receptor (p=0.006), and were borderline significant in RET and EGFR exon. Genomic alterations significantly co-occurred in the tumor suppressor gene ATM with the following genes: SMARCB1, EGFR exon 7, RET and KDR. Clinical factors associated with poor prognosis were ECOG ≥ 2 (p= 0.014), mutations in KDR (p= 0.004) and APC genes (p < 0.001). Conclusions Lung adenocarcinoma patients with WSE showed a distinctive mutated profile for the SMARCB1, ATM, EGFR exon 7, RET and KDR genes. ECOG status and KDR gene mutations were significantly associated with poor prognosis.

Expression profiles in the histological subtypes of lung adenocarcinoma based on the classification of the IASLC/ERS/ATC.

e23226Background: The 2015 WHO/IARC classification of lung adenocarcinoma now classifies lepidic adenocarcinomas as low, acinar and papillary tumors as intermediate, whereas solid and micropapillar...