Esophageal cancer is the sixth leading cause of death from cancer and one of the least studied cancers worldwide. The global microRNA expression profile of esophageal cancer has not been reported previously. Here, for the first time, we have investigated expressed microRNAs in cryopreserved esophageal cancer tissues using advanced microRNA microarray techniques. Our microarray analyses identified seven microRNAs that could distinguish malignant esophageal cancer lesions from adjacent normal tissues. Some microRNAs could be correlated with the different clinicopathologic classifications. High expression of hsa-miR-103/107 correlated with poor survival by univariate analysis as well as by multivariate analysis. These results indicate that microRNA expression profiles are important diagnostic and prognostic markers of esophageal cancer, which might be analyzed simply using economical approaches such as reverse transcription-PCR.

MicroRNA miR-26a and long noncoding RNA (lncRNA) MEG3 gene have been independently reported to be tumor suppressor genes in various cancers, but neither has been previously associated with tongue squamous cell carcinoma (TSCC). We report here that miR-26a and lncRNA MEG3 gene expression were both strongly reduced in TSCC compared with levels in matched nonmalignant tissues, and combined low expression levels of both miR-26a and MEG3 emerged as an independent prognostic factor for poor clinical outcome in TSCC patients. Assays in the human TSCC cell lines SCC-15 and CAL27 showed that miR26a targets the DNA methyltransferase 3B transcript and that its inhibition may result in the upregulation of MEG3, providing a plausible link between the observed reduction of miR-26a and MEG3 in TSCC tissue. Furthermore, the overexpression of miR-26a or MEG3 in SCC-15 and CAL27 cells inhibited cell proliferation and cell cycle progression, and promoted cell apoptosis. Considering the poor prognostic outcomes associated with reduced miR-26a and MEG3, our findings imply that these factors likely play important antitumor effects in TSCC pathogenesis. Furthermore, they represent potential prognostic biomarkers for stratification of TSCC patients.Tongue squamous cell carcinoma (TSCC) is the most common type of oral cancer and is well known for its high rate of proliferation and lymph nodal metastasis. 1 In clinical practice, the prediction of prognosis and planning of treatment for patients suffering from oral cancers are predominantly based on the tumor node metastasis (TNM) staging system. 2 However, in many cases of TSCC, these conventional clinical prognostic factors remain inadequate, and are unable to discriminate tumors of the same clinical stage that may have distinct clinical outcomes and different responses to the same treatments. Therefore, the identification and application of additional biomarkers into the prognostic system that better reflect the biologic diversity of TSCC and consequently predict clinical outcomes more accurately is desirable. 3 Differentially expressed genes identified from hundreds of cancer profiling studies over the last several years have yielded numerous biomarkers that have improved the subtyping, classification and diagnosis of tumors for both research and the clinic. However, the human transcriptome comprises not only large numbers of protein-coding messenger RNAs (mRNAs) but also a large set of noncoding RNAs (ncRNAs) that have structural, regulatory or unknown functions. 4 In TSCC many microRNAs (miRNAs), such as miR-195/184/ 138/21, have been shown to be dysregulated and are believed to contribute to its development and progression. [5][6][7][8] In contrast, long noncoding RNAs (lncRNAs), tentatively defined as ncRNAs more than 200 nt in length, 9 are also known to play key roles in cancer development, 10,11 and aberrant expression of lncRNAs has been functionally associated with lung, breast and prostate carcinomas. 12-14 However, whether lncRNA has relevance to TSCC biology had not been p...

MicroRNAs are small non-coding RNAs that participate in different biological processes, providing subtle combinational regulation of cellular pathways, often by regulating components of signalling pathways. Aberrant expression of miRNAs is an important factor in the development and progression of disease. The canonical myomiRs (miR-1, -133 and -206) are central to the development and health of mammalian skeletal and cardiac muscles, but new findings show they have regulatory roles in the development of other mammalian non-muscle tissues, including nerve, brain structures, adipose and some specialised immunological cells. Moreover, the deregulation of myomiR expression is associated with a variety of different cancers, where typically they have tumor suppressor functions, although examples of an oncogenic role illustrate their diverse function in different cell environments. This review examines the involvement of the related myomiRs at the crossroads between cell development/ tissue regeneration/tissue inflammation responses, and cancer development. Core tip: The roles of the canonical muscle-associated microRNAs are reviewed, including microRNA families miR-1 and miR-133, and single miR-206, which are collectively known as the "myomiRs". The myomiRs act at the crossroads of the molecular regulation of muscle cells, linking between pathways for cell differentiation, development and maintenance, but also potentiate aberrant cell growth in numerous non-muscle cancers. Typically myomiRs are downregulated in cancers, but some myomiRs are upregulated in a few cancers, yet each dysregulation event advances tumor progression. The review examines normal and disease-linked molecular changes associated with the myomiRs, and collates the extensive literature into accessible tables. REVIEW

The N-terminal domains of all four core histones are subject to reversible acetylation at certain lysine residues. This modification has been functionally linked to transcription, histone deposition at replication and to histone removal during spermatogenesis. To increase understanding of the significance of this modification we have studied the specificity of site utilisation in the monoacetyl, diacetyl and triacetyl forms of histones H3, H4 and H2B (histone H2A has only a single modification site), using pig thymus and HeLa cells as the source of histones. The HeLa histones were extracted from cells grown both with and without butyrate treatment. It is found that for histone H3 there is a fairly strict order of site occupancy: Lysl4, followed by Lys23, followed by Lysl8 in both pig and HeLa histones. Since the order and specificity is the same when butyrate is added to the HeLa cell cultures, we conclude that addition of the fatty acid does not scramble the specificity of site utilisation, but merely allows more of the natural forms of modified histone to accumulate. For histone H4, the monoacetyl form is exclusively modified at Lysl6, but further addition of acetyl groups is less specific and progresses through sites 12, 8 and 5 in an N-terminal direction. Similar results were obtained for H4 from both pig thymus and butyratetreated HeLa cells. Histone H2B could be studied in detail only from butyrate-treated HeLa cells and a much lower level of site specificity was found: sites 12 and 15 were preferred to the more N-and C-terminal sites at Lys5 and Lys20. The data reinforces the view that lysine acetylation in core histones is a very specific phenomenon that plays several functionally distinct roles. The high degree of site specificity makes it unlikely that the structural effects of acetylation are mediated merely by a generalised reduction of charge in the histone N-terminal domains.

Purpose: Recent studies have suggested that microRNA biomarkers could be useful for stratifying lung cancer subtypes, but microRNA signatures varied between different populations. Squamous cell carcinoma (SCC) is one major subtype of lung cancer that urgently needs biomarkers to aid patient management. Here, we undertook the first comprehensive investigation on microRNA in Chinese SCC patients.Experimental Design: MicroRNA expression was measured in cancerous and noncancerous tissue pairs strictly collected from Chinese SCC patients (stages I-III), who had not been treated with chemotherapy or radiotherapy prior to surgery. The molecular targets of proposed microRNA were further examined.Results: We identified a 5-microRNA classifier (hsa-miR-210, hsa-miR-182, hsa-miR-486-5p, hsamiR-30a, and hsa-miR-140-3p) that could distinguish SCC from normal lung tissues. The classifier had an accuracy of 94.1% in a training cohort (34 patients) and 96.2% in a test cohort (26 patients). We also showed that high expression of hsa-miR-31 was associated with poor survival in these 60 SCC patients by Kaplan-Meier analysis (P ¼ 0.007), by univariate Cox analysis (P ¼ 0.011), and by multivariate Cox analysis (P ¼ 0.011). This association was independently validated in a separate cohort of 88 SCC patients (P ¼ 0.008, 0.011, and 0.003 in Kaplan-Meier analysis, univariate Cox analysis, and multivariate Cox analysis, respectively). We then determined that the tumor suppressor DICER1 is a target of hsa-miR-31. Expression of hsa-miR-31 in a human lung cancer cell line repressed DICER1 activity but not PPP2R2A or LATS2.Conclusions: Our results identified a new diagnostic microRNA classifier for SCC among Chinese patients and a new prognostic biomarker, hsa-miR-31. Clin Cancer Res; 17(21); 6802-11. Ó2011 AACR.