A high prevalence of hr and lr HPV infections was detected in the OSCC patients included in the study. Moreover, hr HPV positivity was correlated with a decreased 5-year disease-free survival rate compared with HPV- and lr HPV+.
Cancer cells generally rely on aerobic glycolysis as a major source of energy. Methylglyoxal (MG), a dicarbonyl compound that is produced as a side product during glycolysis, is highly reactive and induces the formation of advanced glycation end-products that are implicated in several pathologies including cancer. All mammalian cells have an enzymatic defense against MG composed by glyoxalases GLO1 and GLO2 that converts MG to d-lactate. Colorectal cancer (CRC) is one of the most frequently occurring cancers with high morbidity and mortality. In this study, we used immunohistochemistry to examine the level of MG protein adducts, in a series of 102 CRC human tumors divided into four clinical stages. We consistently detected a high level of MG adducts and low GLO1 activity in high stage tumors compared to low stage ones suggesting a pro-tumor role for dicarbonyl stress. Accordingly, GLO1 depletion in CRC cells promoted tumor growth in vivo that was efficiently reversed using carnosine, a potent MG scavenger. Our study represents the first demonstration that MG adducts accumulation is a consistent feature of high stage CRC tumors. Our data point to MG production and detoxification levels as an important molecular link between exacerbated glycolytic activity and CRC progression.
BackgroundDespite recent advances in colorectal cancer (CRC) diagnosis and population screening programs, the identification of patients with preneoplastic lesions or with early CRC stages remains challenging and is important for reducing CRC incidence and increasing patient’s survival. MethodsWe analysed 76 colorectal tissue samples originated from early CRC stages, normal or inflamed mucosa by label-free proteomics. The characterisation of three selected biomarker candidates was performed by immunohistochemistry on an independent set of precancerous and cancerous lesions harbouring increasing CRC stages.ResultsOut of 5258 proteins identified, we obtained 561 proteins with a significant differential distribution among groups of patients and controls. KNG1, OLFM4 and Sec24C distributions were validated in tissues and showed different expression levels especially in the two early CRC stages compared to normal and preneoplastic tissues.ConclusionWe highlighted three proteins that require further investigations to better characterise their role in early CRC carcinogenesis and their potential as early CRC markers.Electronic supplementary materialThe online version of this article (doi:10.1186/s12014-017-9143-3) contains supplementary material, which is available to authorized users.
Histopathological assessment of ductal carcinoma in situ (DCIS), a non-obligate precursor of invasive breast cancer, is characterized by considerable inter-observer variability. Previously, post hoc dichotomization of multi-categorical variables was used to determine the 'ideal' cut-offs for dichotomous assessment. The present international multi-center study evaluated inter-observer variability among 39 pathologists who performed upfront dichotomous evaluation of 149 consecutive DCIS.All pathologists independently assessed nuclear atypia, necrosis, solid DCIS architecture, calcifications, stromal architecture and lobular cancerization in one digital slide per lesion. Stromal inflammation was assessed semi-quantitatively. Tumor-infiltrating lymphocytes (TILs) were quantified as percentages and dichotomously assessed with a cut-off at 50%. Krippendorff's alpha (KA), Cohen's kappa and intraclass correlation coefficient were calculated for the appropriate variables.Lobular cancerization (KA = 0,396), nuclear atypia (KA = 0,422) and stromal architecture (KA = 0,450) showed the highest inter-observer variability. Stromal inflammation (KA = 0,564), dichotomously assessed TILs (KA = 0,520) and comedonecrosis (KA = 0,539) showed slightly lower inter-observer disagreement. Solid DCIS architecture (KA = 0,602) and calcifications (KA = 0,676) presented with the lowest inter-observer variability. Semi-quantitative assessment of stromal inflammation resulted in a slightly higher inter-observer concordance than upfront dichotomous TILs assessment (KA = 0,564 versus KA = 0,520). High stromal inflammation corresponded best with dichotomously assessed TILs when the cut-off was set at 10% (kappa = 0,881). Nevertheless, a post hoc TILs cut-off set at 20% resulted in the highest inter-observer agreement (KA = 0,669).Despite upfront dichotomous evaluation, the inter-observer variability remains considerable and is at most acceptable, although it varies among the different histopathological features. Future studies should investigate its impact on DCIS prognostication. Forthcoming machine learning algorithms may be useful to tackle this substantial diagnostic challenge.
The classical fate of metastasizing breast cancer cells is to seed and form secondary colonies in bones. The molecules closely associated with these processes are predominantly present at the cell surface and in the extracellular space, establishing the first contacts with the target tissue. In this study, we had the rare opportunity to analyze a bone metastatic lesion and its corresponding breast primary tumor obtained simultaneously from the same patient. Using mass spectrometry, we undertook a proteomic study on cell surface and extracellular proteinenriched material. We provide a repertoire of significantly modulated proteins, some with yet unknown roles in the bone metastatic process as well as proteins notably involved in cancer cell invasiveness and in bone metabolism. The comparison of these clinical data with those previously obtained using a human osteotropic breast cancer cell line highlighted an overlapping group of proteins. Certain differentially expressed proteins are validated in the present study using immunohistochemistry on a retrospective collection of breast tumors and matched bone metastases. Our exclusive set of selected proteins supports the set-up of further investigations on both clinical samples and experimental bone metastasis models that will help to reveal the finely coordinated expression of proteins that favor the development of metastases in the bone microenvironment.
Background and Aims Based on genetics and natural history, Crohn’s disease can be separated into two entities, an ileal and a colonic disease. Protein-based approaches are needed to elucidate whether such subphenotypes are related to distinct pathophysiological processes. Methods The proteome of ulcer edges was compared with that of paired control tissue samples [n = 32 biopsies] by differential proteomics in the ileum and the colon of Crohn’s disease patients [n = 16]. The results were analysed using a hypothesis-driven approach [based on the literature] and a hypothesis-free approach [pathway enrichment analyses] to determine common and segment-specific pathophysiological processes associated with ileal and colonic CD ulcer edges. To confirm the involvement of a key pathway highlighted by proteomics, two proteins were also studied by immunochemistry. Results In the ileum and the colon, 4428 and 5204 proteins, respectively, were identified and quantified. Ileal and colonic ulcer edges differed in having a distinct distribution of proteins associated with epithelial–mesenchymal transition, neutrophil degranulation, and ribosomes. Ileal and colonic ulcer edges were similarly characterized by an increase in the proteins implicated in the endoplasmic reticulum protein-processing pathway and a decrease in mitochondrial proteins. Immunochemistry confirmed the presence of endoplasmic reticulum stress in the mucosa of ileal and colonic ulcer edges. Conclusion This study provides protein-based evidence for partially distinct pathophysiological processes being associated with ileal and colonic ulcer edges in Crohn’s disease patients. This could constitute a first step toward the development of gut segment–specific diagnostic markers and therapeutics.
Barrett's esophagus corresponds to the replacement of the normal esophageal squamous epithelium by a columnar epithelium through a metaplastic process. This tissue remodeling is associated with chronic gastroesophageal reflux and constitutes a premalignant lesion leading to a 30- to 60-fold increase in the risk to evolve into esophageal adenocarcinoma. The present study aimed to investigate a possible immune evasion in Barrett's esophagus favoring esophageal adenocarcinoma development. We demonstrated that myeloid and plasmacytoid dendritic cells are recruited during the esophageal metaplasia-dysplasia-carcinoma sequence, through the action of their chemoattractants, macrophage inflammatory protein 3α and chemerin. Next, we showed that, in contrast to plasmacytoid dendritic cells, myeloid dendritic cells, co-cultured with Barrett's esophagus and esophageal adenocarcinoma cell lines, display a tolerogenic phenotype. Accordingly, myeloid dendritic cells co-cultured with esophageal adenocarcinoma cell lines stimulated regulatory T cell differentiation from naïve CD4(+) T cells. In agreement with those results, we observed that both metaplastic areas and (pre)malignant lesions of the esophagus are infiltrated by regulatory T cells. In conclusion, soluble factors secreted by epithelial cells during the esophageal metaplasia-dysplasia-carcinoma sequence influence dendritic cell distribution and promote tumor progression by rendering them tolerogenic.
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