Predictive molecular markers for EGFR-TKI in non-small cell lung cancer patients: new insights and critical aspects

In recent years, a number of novel agents have been investigated that target specific molecular pathways in non-small cell lung cancer (NSCLC). A great deal of effort has been focused on identifying specific markers that predict treatment response, given that a tailored approach would maximize both the therapeutic index and the cost-effectiveness. The epidermal growth factor receptor (EGFR) pathway has emerged as a key regulator of cancer cell proliferation and invasion, and several specific EGFR inhibitors have been examined. Gefitinib and erlotinib are selective EGFR tyrosine kinase inhibitors (EGFR-TKIs), demonstrating good results in selected cases both in terms of objective response rate and of overall survival. At present, EGFR gene mutations are the best positive predictive factors for TKI therapy, and a number of other potential biomarkers are being investigated as additional positive or negative predictors of response. The correct selection of patients that could benefit from these innovative therapies, based on an accurate molecular characterization, is mandatory to provide the best clinical management. Currently, the main factor limiting the characterization of metastatic NSCLC patients is the small quantity of tumor cells available for molecular analysis. In this paper we provide an overview of the most important molecular predictive markers for EGFR-TKIs therapy in NSCLC patients, and focus attention on biological samples suitable for analysis and alternative sampling approaches such as plasma- or serum-derived DNA

Specific Biomarkers Are Associated with Docetaxeland Gemcitabine-Resistant NSCLC Cell Lines

AbstractFive-year survival rate for lung cancer is limited to 10% to 15%. Therefore, the identification of novel therapeutic prognostic factors is an urgent requirement. The aim of this study is thus to highlight specific biomarkers in chemoresistant non-small cell lung cancer cell lines. Therefore, we checked—in the control condition as well as after short-term pharmacological treatment with either docetaxel or gemcitabine—the expression of genes such as tumor suppressor genes (CDKN2A, DAPK, FHIT, GSTP1, MGMT, RARβ2, RASSF1A, and TIMP3), genes associated with drug resistance (BRCA1, COX2, ERCC1, IGFBP3, RRM1, and TUBB3), and stemness-related genes (CD133, OCT4, and SLUG) in two cellular models of squamous carcinoma (CAEP) and adenocarcinoma (RAL) of the lung originally established. Their promoter methylation profile was also evaluated. Drug-related genes were upregulated. Cisplatin resistance matched with high levels of BRCA1 and ERCC1 in both cell lines; docetaxel sensitivity of CAEP cells was associated to levels of TUBB3 lower than RAL cells. Although CAEP cells were more sensitive to gemcitabine, both cell lines showed high levels of RRM1. Stemness-related genes were downregulated in the control condition but became upregulated in docetaxel-resistant cells, indicating the selection of a population with stemness features. We did not find an unequivocal correspondence between gene expression and respective DNA promoter methylation status, suggesting the involvement of additional mechanisms of gene expression regulation. These results highlight specific biomarkers consistent with the different responses of the two cell lines to standard pharmacological treatments and indicate specific molecular traits for their chemoresistance

Improved stool DNA integrity method for early colorectal cancer diagnosis

Background: DNA integrity analysis could represent an alternative approach to the early detection of colorectal cancer. Previously, fluorescence long DNA (FL-DNA) in stools was extracted using a manual approach and analyzed by capillary electrophoresis assay (CE FL-DNA). We aimed to improve diagnostic accuracy using a simpler and more standardized method [Real Time PCR FL-DNA (RT FL-DNA)] for the detection of early malignant lesions in a population undergoing colorectal cancer screening. Methods: From 241 stool samples,DNAwas extracted using manual and semiautomatic extraction systems and analyzed using FL-DNA tests by CE and RT assays. The RT FL-DNA approach showed slightly higher sensitivity and specificity compared with the CEFL-DNA method. Furthermore, we compared the RTFL-DNA approach with the iFOBT report. Results: Nonparametric ranking statistics were used to analyze the relationship between the median values of RT FL-DNA and the clinicohistopathologic characteristics. The median values of both variables were significantly higher in patients with cancer than in patients with noncancerous lesions. According to the Fagan nomogram results, the iFOBT and FL-DNA methods provided more accurate diagnostic information and were able to identify subgroups at varying risks of cancer. Conclusions: The combination of the semiautomatic extraction system and RT FL-DNA analysis improved the quality of DNA extracted from stool samples. Impact: RT FL-DNAshows great potential for colorectal cancer diagnosis as it is a reliable and relatively easy analysis to perform on routinely processed stool samples in combination with iFOBT

fMRI in Bell's Palsy: cortical activation is associated with clinical status in the acute and recovery phases

BACKGROUND: Using functional MRI (fMRI), we explored cortical activation in patients with acute Bell’s palsy (BP) and analyzed its correlates with clinical status in the acute phase, and with 6-monthoutcome. METHODS: 24 right-handed patients with acute BP within 15 days of onset and 24 healthy controls underwent fMRI during performance of unilateral active (hemi-smiling) and passive lip movement tasks with both the paretic and the normal lip. The degree of paresis was evaluated during the acute stage and at the 6-month follow-up using the House-Brackmann (HB) grading scale. Complete recovery was defined as HB grade II or less at the end of the 6-month period. The difference in the HB grade (ΔHB) between the acute stage and the 6-month follow up was used to evaluate clinical improvement. RESULTS: There were 24 patients with unilateral acute BP. HB grades ranged from III to VI. At six months, 11 patients (46%) had completely recovered and 12 (50%) were partially improved. Compared with healthy subjects, BP patients had a significantly greater activation of the frontal areas and the insula ipsilateral to the paretic side. In BP patients, there was an inverse correlation between the activation of the ipsilateral hemisphere when moving the paretic side and the degree of paresis at baseline. An association was also observed between activation and clinical outcome (both complete recovery and ΔHB). CONCLUSIONS: In patients with Bell’s palsy, fMRI may represent a useful tool to predict long-term outcome, guide therapeutic approach, and monitor treatment response

Genomic alterations in rectal tumors and response to neoadjuvant chemoradiotherapy: an exploratory study

<p>Abstract</p> <p>Background</p> <p>Neoadjuvant chemoradiotherapy is the treatment of choice in advanced rectal cancer, even though there are many patients who will not benefit from it. There are still no effective methods for predicting which patients will respond or not. The present study aimed to define the genomic profile of rectal tumors and to identify alterations that are predictive of response in order to optimize therapeutic strategies.</p> <p>Methods</p> <p>Forty-eight candidates for neoadjuvant chemoradiotherapy were recruited and their pretherapy biopsies analyzed by array Comparative Genomic Hybridization (aCGH). Pathologic response was evaluated by tumor regression grade.</p> <p>Results</p> <p>Both Hidden Markov Model and Smoothing approaches identified similar alterations, with a prevalence of DNA gains. Non responsive patients had a different alteration profile from responsive ones, with a higher number of genome changes mainly located on 2q21, 3q29, 7p22-21, 7q21, 7q36, 8q23-24, 10p14-13, 13q12, 13q31-34, 16p13, 17p13-12 and 18q23 chromosomal regions.</p> <p>Conclusions</p> <p>This exploratory study suggests that an in depth characterization of chromosomal alterations by aCGH would provide useful predictive information on response to neoadjuvant chemoradiotherapy and could help to optimize therapy in rectal cancer patients.</p> <p>The data discussed in this study are available on the NCBI Gene Expression Omnibus [GEO: GSE25885].</p

Right- vs. left-sided metastatic colorectal cancer: Differences in tumor biology and bevacizumab efficacy

There is evidence of a different response to treatment with regard to the primary tumor localization (right-sided or left-sided) in patients with metastatic colorectal cancer (mCRC). We analyzed the different outcomes and biomolecular characteristics in relation to tumor localization in 122 of the 370 patients with metastatic colorectal cancer enrolled onto the phase III prospective multicenter “Italian Trial in Advanced Colorectal Cancer (ITACa)”, randomized to receive first-line chemotherapy (CT) or CT plus bevacizumab (CT + B). RAS and BRAF mutations; baseline expression levels of circulating vascular endothelial growth factor (VEGF), endothelial nitric oxide synthase (eNOS), cyclooxygenase-2 (COX2), ephrin type-B receptor 4 (EPHB4), hypoxia-inducible factor 1-alpha (HIF-1α), lactate dehydrogenase (LDH), and high-sensitivity C reactive protein (hs-CRP); and inflammatory indexes such as the neutrophil-to-lymphocyte ratio, platelet-lymphocyte rate and systemic immune-inflammation index were evaluated. Patients with right-sided tumors showed a longer median progression-free survival in the CT + B arm than in the CT group (12.6 vs. 9.0 months, respectively, p = 0.017). Baseline inflammatory indexes were significantly higher in left-sided tumors, whereas eNOS and EPHB4 expression was significantly higher and BRAF mutation more frequent in right-sided tumors. Our data suggest a greater efficacy of the CT + B combination in right-sided mCRC, which might be attributable to the lower inflammatory status and higher expression of pro-angiogenic factors that appear to characterize these tumors

Contribution of MUTYH variants to male breast cancer risk: results from a multicenter study in Italy

Inherited mutations in BRCA1, and, mainly, BRCA2 genes are associated with increased risk of male breast cancer (MBC). Mutations in PALB2 and CHEK2 genes may also increase MBC risk. Overall, these genes are functionally linked to DNA repair pathways, highlighting the central role of genome maintenance in MBC genetic predisposition. MUTYH is a DNA repair gene whose biallelic germline variants cause MUTYH-associated polyposis (MAP) syndrome. Monoallelic MUTYH variants have been reported in families with both colorectal and breast cancer and there is some evidence on increased breast cancer risk in women with monoallelic variants. In this study, we aimed to investigate whether MUTYH germline variants may contribute to MBC susceptibility. To this aim, we screened the entire coding region of MUTYH in 503 BRCA1/2 mutation negative MBC cases by multigene panel analysis. Moreover, we genotyped selected variants, including p.Tyr179Cys, p.Gly396Asp, p.Arg245His, p.Gly264Trpfs*7, and p.Gln338His, in a total of 560 MBC cases and 1,540 male controls. Biallelic MUTYH pathogenic variants (p.Tyr179Cys/p.Arg241Trp) were identified in one MBC patient with phenotypic manifestation of adenomatous polyposis. Monoallelic pathogenic variants were identified in 14 (2.5%) MBC patients, in particular, p.Tyr179Cys was detected in seven cases, p.Gly396Asp in five cases, p.Arg245His and p.Gly264Trpfs*7 in one case each. The majority of MBC cases with MUTYH pathogenic variants had family history of cancer including breast, colorectal, and gastric cancers. In the case-control study, an association between the variant p.Tyr179Cys and increased MBC risk emerged by multivariate analysis [odds ratio (OR) = 4.54; 95% confidence interval (CI): 1.17-17.58; p = 0.028]. Overall, our study suggests that MUTYH pathogenic variants may have a role in MBC and, in particular, the p.Tyr179Cys variant may be a low/moderate penetrance risk allele for MBC. Moreover, our results suggest that MBC may be part of the tumor spectrum associated with MAP syndrome, with implication in the clinical management of patients and their relatives. Large-scale collaborative studies are needed to validate these findings

Rearrangements of ATP5L-KMT2A in acute lymphoblastic leukaemia

Recent genomic studies have identified a wide range of novel genetic alterations that have substantially increased our knowledge of the biology of B- and T-progenitor acute lymphoblastic leukaemia (B-ALL, T-ALL) and defined new subtypes with prognostic and therapeutic relevance.1-4 Thanks to the use of transcriptome sequencing approaches, new cryptic fusion transcripts have been described, such as the ATP5L-KMT2A gene fusion, described by Gestrich et al. in a 14-month-old patient with aggressive B-ALL.5 ATP5L or ATP5MG (ATP Synthase Membrane Subunit G) catalyzes ATP synthesis during oxidative phosphorylation.6 This protein has recently been reported to interact with a SARS-CoV-2 protein.7 The histone lysine [K]-methyl transferase 2A (KMT2A) gene is a transcriptional coactivator that plays an essential role in regulating gene expression during early development and haematopoiesis. It is frequently rearranged to over 135 translocation partner genes in acute leukaemias.8 ATP5L is a novel KMT2A fusion partner not detectable by fluorescent in situ hybridization (FISH) or karyotype, due to the closeness of the two genes on chromosome 11q23. The Cleveland Medical Centre team found a reciprocal out-of-frame ATP5L-KMT2A rearrangement that juxtaposes the ATP5L exon 1 to the KMT2A exon 2, with the insertion of an extra nucleotide (G) at the fusion site.5 We sequenced leukaemic cells from eight adult ALL patients (two T-ALL, five B-ALL Philadelphia negative (Ph−) and one B-ALL Ph+; Table I) by a 199 gene RNA-sequencing panel (RNA-seq; Pan-Heme FusionPlex, ArcherDx Inc., Boulder, CO, USA).The study was supported by European Union Seventh Framework Programme (FP7/2007-2013) (GA 306242-NGS-PTL) and Associazione Italiana Leucemie (AIL)

Promoter methylation of tumor suppressor genes in pre-neoplastic lesions; Potential marker of disease recurrence

Background: Epigenetic alterations of specific genes have been reported to be related to colorectal cancer (CRC) transformation and would also appear to be involved in the early stages of colorectal carcinogenesis. Little data are available on the role of these alterations in determining a different risk of colorectal lesion recurrence. The aim of the present study was to verify whether epigenetic alterations present in pre-neoplastic colorectal lesions detected by colonoscopy can predict disease recurrence. Methods. A retrospective series of 78 adenomas were collected and classified as low (35) or high-risk (43) for recurrence according to National Comprehensive Cancer Network guidelines. Methylation alterations were analyzed by the methylation-specific multiplex ligation probe assay (MS-MLPA) which is capable of quantifying methylation levels simultaneously in 24 different gene promoters. MS-MLPA results were confirmed by pyrosequencing and immunohistochemistry. Results: Higher levels of methylation were associated with disease recurrence. In particular, MLH1, ATM and FHIT gene promoters were found to be significantly hypermethylated in recurring adenomas. Unconditional logistic regression analysis used to evaluate the relative risk (RR) of recurrence showed that FHIT and MLH1 were independent variables with an RR of 35.30 (95% CI 4.15-300.06, P = 0.001) and 17.68 (95% CI 1.91-163.54, P = 0.011), respectively. Conclusions: Histopathological classification does not permit an accurate evaluation of the risk of recurrence of colorectal lesions. Conversely, results from our methylation analysis suggest that a classification based on molecular parameters could help to define the mechanisms involved in carcinogenesis and prove an effective method for identifying patients at high risk of recurrence

Shifts of Faecal Microbiota during Sporadic Colorectal Carcinogenesis

Gut microbiota has been implicated in the etiopathogenesis of colorectal cancer. The development of colorectal cancer is a multistep process by which healthy epithelium slowly develops into preneoplastic lesions, which in turn progress into malignant carcinomas over time. In particular, sporadic colorectal cancers can arise from adenomas (about 85% of cases) or serrated polyps through the "adenoma-carcinoma" or the "serrated polyp-carcinoma" sequences, respectively. In this study, we performed 16 S rRNA gene sequencing of bacterial DNA extracted from faecal samples to compare the microbiota of healthy subjects and patients with different preneoplastic and neoplastic lesions. We identified putative microbial biomarkers associated with stage-specific progression of colorectal cancer. In particular, bacteria belonging to the Firmicutes and Actinobacteria phyla, as well as members of the Lachnospiraceae family, proved to be specific of the faecal microbiota of patients with preneoplastic lesions, including adenomas and hyperplastic polyps. On the other hand, two families of the Proteobacteria phylum, Alcaligeneaceae and Enterobacteriaceae, with Sutterella and Escherichia/Shigella being the most representative genera, appeared to be associated with malignancy. These findings, once confirmed on larger cohorts of patients, can represent an important step towards the development of more effective diagnostic strategies