Microrna Copy Number Abnormalitie Kelainan Nomor Salin Microrna Di Kanker Kolorektal Keluarga

Background The majority of the familial colorectal cancer (CRC) cases cannot be explained by known gene defects, suggesting the existence of other genetic risk factors. In an approach to identify such risk factors, we recently performed a screen for copy number variations (CNVs) in highrisk CRC patients and found, among other lesions, several small deletions affecting microRNA genes. MicroRNAs are negative regulators of approximately 30% of the genes in the human genome, including numerous tumor suppressor genes and oncogenes. Methods In order to comprehensively investigate copy number variation in microRNA genes, and to reveal whether such variations may affect CRC predisposition, we screened for CNVs affecting microRNA genes in 17 unexplained familiar early-onset CRC patients using a custom made ultimate (tiling) resolution oligo array containing 695 miR genes. We performed MLPA, q-PCR and PCR to validate all CNVs candidate. Results We found various small (0.2 - 23 kb) constitutional deletions and duplications affecting single microRNA genes. Several of these CNVs, validated using PCR-based technique, were only detected in patients and not in controls. For example miR-646 was found to be duplicated in patient but in 250 controls no duplication was found. MiR-770 was deleted in another patient, whereas no CNVs at this position were found in 94 controls. Conclusion We conclude that CNVs of smaller size (<1 Mb) affecting miRNA genes do occur and can be identified using custom oligo array. Nevertheless, further optimization needs to be done to reduce the noise and false positive results generated which complicate the validation process. On the other hand using an in-house database, some of the miRs are indeed affected by polymorphic CNVs and many others are still unknown. Overall we showed CNVs in microRNA genes are more common than previously thought, and some of them may be associated with CRC predisposition. Keywords: Familial colorectal cancer, copy number variations, microRNA, microarra

Differential expression of major histocompatibility complex class I in developmental glioneuronal lesions

The expression of the major histocompatibility complex class I (MHC-I) in the brain has received considerable interest not only because of its fundamental role in the immune system, but also for its non-immune functions in the context of activity-dependent brain development and plasticity. In the present study we evaluated the expression and cellular pattern of MHC-I in focal glioneuronal lesions associated with intractable epilepsy. MHC-I expression was studied in epilepsy surgery cases with focal cortical dysplasia (FCD I, n = 6; FCD IIa, n = 6 and FCD IIb, n = 15), tuberous sclerosis complex (TSC, cortical tubers; n = 6) or ganglioglioma (GG; n = 15) using immunocytochemistry. Evaluation of T lymphocytes with granzyme-B+ granules and albumin immunoreactivity was also performed. All lesions were characterized by MHC-I expression in blood vessels. Expression in both endothelial and microglial cells as well as in neurons (dysmorphic/dysplastic neurons) was observed in FCD II, TSC and GG cases. We observed perivascular and parenchymal T lymphocytes (CD8+, T-cytotoxic) with granzyme-B+ granules in FCD IIb and TSC specimens. Albumin extravasation, with uptake in astrocytes, was observed in FCD IIb and GG cases. Our findings indicate a prominent upregulation of MHC-I as part of the immune response occurring in epileptogenic glioneuronal lesions. In particular, the induction of MHC-I in neuronal cells appears to be a feature of type II FCD, TSC and GG and may represent an important accompanying event of the immune response, associated with blood-brain barrier dysfunction, in these developmental lesion

Long intervening non-coding RNA 00320 is human brain-specific and highly expressed in the cortical white matter

Pervasive transcription of the genome produces a diverse array of functional non-coding RNAs (ncRNAs). One particular class of ncRNAs, long intervening non-coding RNAs (lincRNAs) are thought to play a role in regulating gene expression and may be a major contributor to organism and tissue complexity. The human brain with its heterogeneous cellular make-up is a rich source of lincRNAs; however, the functions of the majority of lincRNAs are unknown. Recently, by completing RNA sequencing (RNA-Seq) of the human frontal cortex, we identified linc00320 as being highly expressed in the white matter compared to grey matter in multiple system atrophy (MSA) brain. Here, we further investigate the expression patterns of linc00320 and conclude that it is involved in specific brain regions rather than having involvement in the MSA disease process. We also show that the full-length linc00320 is only expressed in human brain tissue and not in other primates, suggesting that it may be involved in improved functional connectivity for higher human brain cognitio

Effect of anti-miR-146a LNA or miR-146a mimic upon IL-1β-induced COX-2 protein and release of HMGB1.

<p>COX-2 protein expression 24 hours after exposure to IL-1β in U373 cells transfected with LNA-antimiR-146a (50 nM) or miR-146a mimic (pre-mir-146a, 50 nM). (<b>A</b>) Representative immunoblot and (<b>B</b>) densitometric analysis: values (optical density units relative to the optical density of β-actin) are mean ± SEM of two separate experiments performed and are expressed relative to the levels in unstimulated cells. (<b>C</b>) HMGB1 immunoblot (1 control; 2, IL-1β; 3, IL-1β + mimic; 4, IL-1β + mimic scramble; 5 mimic; 6, IL-1β + LNA-antimiR-146a; 7, IL-1β + LNA-antimiR-146a scramble 8, LNA) and densitometric analysis (<b>D</b>, optical density units of cellular HMGB1 relative to the optical density of β-actin). *p<0.05, compared to control; **p<0.05, LNA or mimic transfected cells stimulated with IL-1β compared to IL-1β alone.</p

miR-146a expression levels in cultured human astrocytes after exposure to IL-1β.

<p>Quantitative real-time PCR of miR-146a expression in human fetal astrocytes in culture. (<b>A</b>) Expression levels of miR-146a 24 hours after exposure to IL-1β (10 ng/ml) or LPS (100 ng/ml) in the presence or absence of the IL-1β receptor antagonist (IL-1ra; 1 µg/ml) or LPS-RS (10 µg/m) respectively. (<b>B</b>) Expression levels of miR-146a 24 hours after exposure to IL-1β (10 ng/ml), TNFα (1 ng/ml), IL-6 (10 ng/ml), HMGB1 (40 nM). (<b>C</b>) Expression levels of miR-146a 24 hours after to 0.1, 1, 10 or 50 ng/ml of IL-1β. (<b>D</b>) Expression levels of miR-146a in cells incubated for different times (10, 30, 60 min and 6, 16, 24, 48) hours in the presence of IL-1β (10 ng/ml). Data are expressed relative to the levels observed in unstimulated cells and are mean ± SEM from two separate experiments performed in triplicate (*p<0.05 compared to control).</p

miR-146a expression levels in U373 glioblastoma cell line after exposure to IL-1β.

<p>Quantitative real-time PCR of miR-146a expression in U373 cells in culture. (<b>A</b>) Expression levels of miR-146a 24 hours after exposure to IL-1β (10 ng/ml) or LPS (100 ng/ml) in the presence or absence of the IL-1β receptor antagonist (IL-1ra; 1 µg/ml) or LPS-RS (10 µg/ml) respectively. (<b>B</b>) Expression levels of miR-146a 24 hours after exposure to IL-1β (10 ng/ml), TNFα (1 ng/ml), IL-6 (10 ng/ml), HMGB1 (40 nM alone or in the presence of IL-1β). (<b>C</b>) Expression levels of miR-146a 24 hours after exposure to 0.1, 1, 10 or 50 ng/ml of IL-1β. (<b>D</b>) Expression levels of miR-146a in U373 cells incubated for different durations (10, 30, 60 min and 6, 16, 24, 48) hours in the presence of IL-1β (10 ng/ml). Data are expressed relative to the levels observed in unstimulated cells and are mean ± SEM from two separate experiments performed in triplicate (*p<0.05 compared to control).</p