Uncovering the relationship between YAP/ WWTR1 (TAZ) genes expression and LncRNAs of SNHG15, HCP5 and LINC01433 in breast cancer tissues

In spite of the decrease in breast cancer (BC) death rates, it has remained a significant public health concern. Dysregulation of the Hippo pathway contributes to breast cancer development and progression by enhancing cancerous cell proliferation, survival, invasion, and migration. Investigating the connection between specific lncRNAs (SNHG15, HCP5, and LINC01433) and YAP and WWTR1, and the impact of these lncRNAs on the expression of YAP and WWTR1 proteins in the Hippo pathway, may offer valuable understanding for BC diagnosis and treatment. Forty BC tissue samples were acquired from the Tumor Bank and utilized for RNA and protein extraction. Real-time PCR and western blotting techniques were performed to assess the gene and protein expressions, respectively. Correlations between variables and their associations with clinicopathological features in BC were evaluated using Mann-Whitney U or Student's t-test. Additionally, the analysis of the GEO database was utilized to validate the findings. In cancerous tissue, the up-regulation of YAP, WWTR1, HCP5, SNHG15, and Linc01433 at both the mRNA and protein levels corresponds to the findings in GEO datasets. A significant association was found between YAP and histological grade, while WWTR1 showed a correlation with family history and HER-2. The distinct and notable expression of YAP, WWTR1, SNHG15, HCP5, and Linc01433 in BC tissues, together with the results of combined ROC curve analysis derived from our finding and GEO database suggest that a combined panel of these 5 RNAs may have great potential in predicting of BC and its management.

High LGALS3 expression induced by HCP5/hsa-miR-27b-3p correlates with poor prognosis and tumor immune infiltration in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is widely recognized for its unfavorable prognosis. Increasing evidence has revealed that LGALS3 has an essential function in initiating and developing several malignancies in humans. Nevertheless, thorough analysis of the expression profile, clinical prognosis, pathway prediction, and immune infiltration of LGALS3 has not been fully explored in HCC.

METHODS

In this study, an initial pan-cancer analysis was conducted to investigate the expression and prognosis of LGALS3. Following a comprehensive analysis, which included expression analysis and correlation analysis, noncoding RNAs that contribute to the overexpression of LGALS3 were subsequently identified. This identification was further validated using HCC clinical tissue samples. TIMER2 and GEPIA2 were employed to examine the correlation between LGALS3 and HCP5 with immunological checkpoints, cell chemotaxis, and immune infiltration in HCC. The R program was applied to analyze the expression distribution of immune score in in HCC patients with high and low LGALS3 expression. The expression profiles of immune checkpoints were also analyzed. Use R to perform GSVA analysis in order to explore potential signaling pathways.

RESULTS

First, we conducted pan-cancer analysis for LGALS3 expression level through an in-depth analysis of public databases and found that HCC has a high LGALS3 gene and protein expression level, which were then verified in clinical HCC specimens. Meanwhile, high LGALS3 gene expression is related to malignant progression and poor prognosis of HCC. Univariate and multivariate analyses confirmed that LGALS3 could serve as an independent prognostic marker for HCC. Next, by combining comprehensive analysis and validation on HCC clinical tissue samples, we hypothesize that the HCP5/hsa-miR-27b-3p axis could serve as the most promising LGALS3 regulation mechanism in HCC. KEGG and GO analyses highlighted that the LGALS3-related genes were involved in tumor immunity. Furthermore, we detected a significant positive association between LGALS3 and HCP5 with immunological checkpoints, cell chemotaxis, and immune infiltration. In addition, high LGALS3 expression groups had significantly higher immune cell scores and immune checkpoint expression levels. Finally, GSVA analysis was performed to predict potential signaling pathways linked to LGALS3 and HCP5 in immune evasion and metabolic reprogramming of HCC.

CONCLUSIONS

Our findings indicated that the upregulation of LGALS3 via the HCP5/hsa-miR-27b-3p axis is associated with unfavorable prognosis and increased tumor immune infiltration in HCC.

CRISPR du-HITI an attractive approach to targeting Long Noncoding RNA HCP5 as inhibitory factor for proliferation of ovarian cancer cell

This research provides a glimmer of hope that the knockout of HCP5 leads to a therapy response to considerably prolong the life of patients with OC. RT-PCR evaluated the expression of lncRNA HCP5 in the ovarian cancer OVCAR-3 cell line. CRISPR knockout cell lines validated by western blot. Small genomic deletions at the targeted locus were induced. CCK-8 colony formation assays were used to analyze the effect of HCP5 knockout on the proliferation capacity of OVCAR-3 cells. Transwell migration and invasion assayed. Furthermore, the Sphere-formation assay isolated the most aggressive population of cancer stem cells. Bioinformatic analysis showed a significant correlation between lncRNA HCP5 up-regulation and OVCAR-3 cell proliferation. The ChIP technique assesses specific sites of interaction between transcription factors and DNA. Real-time PCR assays explored the relationship between HCP5, Hsa-miR-9-5p, CXCR4, CDH1, caspase-3, p53, bcl2 and survivin. PCR carried out amplification of the 448-bp band for sgRNA1 and sgRNA2 after the use of particular primers for HCP5. the number of breast cancer cells that moved to the bottom chamber reduced considerably after transfection with PX461-sgRNA1/2 vectors compared to the Blank control groups (P < 0.05). MTT assay designated growth curves that showed the rate of OVCAR-3 growth was significantly repressed (***P < 0.001) when compared with control OVCAR-3 cells after HCP5 knockdown. Also, the survival results of W.T cells in 24, 48 and 72 h showed 92%, 87% and 85%, respectively. This is while the cells of the CRISPR/Cas9 group in which LncRNA HCP5 was knocked out had 42% (*P < 0.05), 23%(**P < 0.01) and 14% (**P < 0.01) survival, respectively. The expression levels of caspase-3, Hsa-miR-9-5p, P53 genes in the HCP5 deletion of CRISPR/Cas9 group significantly increased than the W.T. control group; the deletion group showed a considerable reduction in HCP5 expression compared to the blank control group (3.6-fold, p < 0.01). Whereas BCL2, SURVIVIN, CXCR4, CDH1 genes expression markedly increased than in HCP5 knockout cells (5.8-fold, p < 0.05). These results indicate that CRISPR/Cas9-mediated HCP5 disruption on OVCAR-3 cell lines promotes anti-tumor biomarkers, suppressing ovarian cancer progression. Consistent with these results, HCP5 is one of the most critical lnc for the efficient proliferation and migration of OVCAR-3 cell lines.

LncRNA HCP5 is Highly Expressed in Gestational Diabetes Mellitus to Suppress Insulin Secretion

Purpose

LncRNA HCP5 has been reported to participate in high glucose-induced pathological processes, whereas its role in gestational diabetes mellitus (GDM) is unclear. This study aimed to explore the role of HCP5 in GDM.

Methods

This study enrolled a total of 220 pregnant women (gestational age = 1 month). A follow-up study was performed until delivery. The occurrence of GDM was checked every month during follow-up. Plasma samples were collected from all participants and expression of HCP5 was determined with RT-qPCR. The 220 patients were divided into high and low GDM groups, and GDM-free curves were plotted for both groups and compared. The ROC curve was plotted to explore the predictive value of plasma HCP5 on the day of admission for GDM. INS-1 cells were transfected with HCP5 expression vector or siRNA, and cell viability under high glucose was determined by the MTT assay. An ELISA was applied to determine insulin levels in the cell culture medium.

Results

During follow-up, the level of HCP5 was increased during pregnancy and the high HCP5 level group showed a significantly higher incidence of GDM. Plasma levels of HCP5 on the day of admission effectively separated GDM patients from healthy controls. HCP5 negatively regulated cell viability and insulin secretion under high glucose treatment.

Conclusion

HCP5 may act as a predictor for GDM, and it negatively regulated INS-1 cell viability and insulin secretion under high glucose conditions.

PD-1/PD-L1 Inhibitors Response in Triple-Negative Breast Cancer: Can Long Noncoding RNAs Be Associated?

As immune checkpoint inhibitors (ICI) emerge as a paradigm-shifting treatment option for patients with advanced or metastatic cancer, there is a growing demand for biomarkers that can distinguish which patients are likely to benefit. In the case of triple-negative breast cancer (TNBC), characterized by a lack of therapeutic targets, pembrolizumab approval for high-risk early-stage disease occurred regardless of PD-L1 status, which keeps the condition in a biomarker limbus. In this review, we highlight the participation of long non-coding RNAs (lncRNAs) in the regulation of the PD-1/PD-L1 pathway, as well as in the definition of prognostic immune-related signatures in many types of tumors, aiming to shed light on molecules that deserve further investigation for a potential role as biomarkers. We also conducted a bioinformatic analysis to investigate lncRNAs already investigated in PD-1/PDL-1 pathways in other cancer types, considering the TNBC molecular context. In this sense, from the generated data, we evidence here two lncRNAs, UCA1 and HCP5, which have not yet been identified in the context of the tumoral immune response in breast cancer. These candidates can be further explored to verify their use as biomarkers for ICI response. In this article, we present an updated review regarding the use of lncRNA as biomarkers of response to ICI, highlighting the versatility of using these molecules.

LncRNA HCP5 acts as a miR-128-3p sponge to promote the progression of multiple myeloma through activating Wnt/β-catenin/cyclin D1 signaling via PLAGL2

BACKGROUND

Although long non-coding RNA (lncRNA) HCP plays essential roles in human cancers, its function and mechanism in multiple myeloma (MM) have not crystallized.

METHODS

HCP5 level in MM was assessed through qRT-PCR. A series of functional investigations were conducted to evaluate the influences of HCP5 on proliferation and apoptosis. Bioinformatics analysis and RIP/RNA pull-down assays were carried out to determine the relationships among HCP5, miR-128-3p, and PLAGL2. Relative protein level was determined through Western blot. A xenograft tumor model was applied for validating the roles of HCP5/miR-128-3p/PLAGL2 axis in vivo.

RESULTS

HCP5 was significantly increased in MM. HCP5 knockdown effectively thwarted the proliferative rate and cell cycle of MM cell lines and suppressed tumor growth. HCP5 regulated PLAGL2 expression by sponging miR-128-3p. PLAGL2 overexpression effectively rescued cells from influences by sh-HCP5 on cell proliferative and apoptotic rates. Additionally, HCP5 knockdown significantly inhibited Wnt/β-catenin/cyclin D1 signaling, and these effects were eliminated by PLAGL2 overexpression.

CONCLUSION

Our study revealed that HCP5/miR-128-3p/PLAGL2 is closely correlated to MM development by modulating Wnt/β-catenin/cyclin D1 signaling. HCP5 promoted cell proliferation and tumor formation of MM cells by activating the Wnt/β-catenin/CCND1 signaling pathway by sponging miR-128-3p to increase PLAGL2 expression.

Overexpression of lncRNA HCP5 in human umbilical cord mesenchymal stem cell-derived exosomes promoted the proliferation and inhibited the apoptosis of ovarian granulosa cells via the musashi RNA-binding protein 2/oestrogen receptor alpha 1 axis

HCP5 has been reported to be downregulated in ovarian granulosa cells (OGCs) and to facilitate cell proliferation. Human umbilical cord mesenchymal stem cell exosome (hucMSCs-exo) treatment can prevent OGCs apoptosis in vitro. However, the functional mechanism of HCP5 and hucMSCs-exo requires further exploration. Fluorescence-activated cell sorting (FACS) was performed to measure the expression of markers related to hucMSCs. The osteogenic and adipogenic potential of hucMSCs was measured by alkaline phosphatase (ALP) and Alizarin red and by oil red-O staining, respectively. Real-time quantitative polymerase chain reaction (RT-qPCR) and Western blotting were used to detect the mRNA and protein levels, respectively. Cell proliferation and apoptosis were measured by Cell Counting Kit-8 (CCK-8) assay, colony formation assay and flow cytometry. The interaction of HCP5/musashi RNA-binding protein 2 (MSI2) and oestrogen receptor alpha 1 (ESR1) mRNA was analysed using RNA pulldown and RIP assays. HucMSCs and exosomes were successfully isolated and identified. HucMSC-derived exosomes promoted the proliferation of OGCs and ESR1 expression and inhibited cell apoptosis. HCP5 overexpression in exosomes further enhanced these effects. MSI2 knockdown led to the opposite results. HCP5 targeted MSI2, and MSI2 knockdown reduced the decreases in HCP5 and ESR1 expression. Mechanistically, HCP5 in HucMSC-derived exosomes promoted ESR1 expression by binding to MSI2, which promoted the proliferation of OGCs.

miR-17-5p/HOXA7 Is a Potential Driver for Brain Metastasis of Lung Adenocarcinoma Related to Ferroptosis Revealed by Bioinformatic Analysis

Objectives

Present study aims to identify the essential mRNAs responsible for the development of brain neurovascular-related metastases (BNM) among lung adenocarcinoma (LUAD) patients. Further, we attempted to predict brain metastases more accurately and prevent their development in LUAD patients.

Methods

Transcriptome data analysis was used to identify differentially expressed mRNAs (DEMs) associated with brain metastasis, and thereby the ferroptosis index (FPI) is calculated using a computational model. Meanwhile, the DEmRNAs linked with FPI, and brain metastasis were derived by the intersection of these two groups of DEMs. We also constructed a ceRNA network containing these DEmRNAs, identifying the HCP5 /hsa-miR-17-5p/HOXA7 axis for analysis. Further, a clinical cohort was employed to validate the regulatory roles of molecules involved in the ceRNA regulatory axis.

Results

Here we report the development of a ceRNA network based on BNM-associated DEMs and FPI-associated DEmRNAs which includes three core miRNAs (hsa-miR-338-3p, hsa-miR-429, and hsa-miR-17-5p), three mRNAs (HOXA7, TBX5, and TCF21), and five lncRNAs (HCP5, LINC00460, TP53TG1). Using gene set enrichment analysis (GSEA) and survival analysis, the potential axis of HCP5 /hsa-miR-17-5p/HOXA7 was further investigated. It is found that HOXA7 and ferroptosis index are positively correlated while inhibiting tumor brain metastasis. It may be that HCP5 binds competitively with miR-17-5p and upregulates HOXA7 to increase iron death limiting brain cancer metastases.

Conclusions

The expression of both HOXA7 and HCP5 is positively correlated with FPI, indicating a possible link between ferroptosis and BNM. According to the results of our study, the ferroptosis-related ceRNA HCP5 /hsa-miR-17-5p/HOXA7 axis may contribute to the development of BNM in LUAD patients.

HLA complex P5 upregulation is correlated with poor prognosis and tumor progression in esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is a deadly malignant tumor that threatens human health. Long noncoding RNA (lncRNA) is widely expressed in eukaryotes and is closely associated with human disease progression. However, its role in ESCC remains incompletely understood. In this study, we analyzed the results of three gene expression omnibus (GEO) databases containing lncRNA expression data of ESCC and normal tissues. The results showed that HCP5 was significantly overexpressed in ESCC tissues, which was further verified in our collected ESCC samples. The functional study suggested that HCP5 knockdown inhibited ESCC cell proliferation and invasion. Regarding the mechanism, HCP5 was able to directly interact with YTHDF1, a N6-methyladenosine (m⁶A) reader, enhancing the binding of YTHDF1 to m⁶A-modified HK2 mRNA, leading to increasing HK2 stability, thereby promoting the Warburg effect (aerobic glycolysis) of ESCC cells. The nude mice model showed that the knockdown of HCP5 in vivo remarkably reduced tumor size. Clinically, high HCP5 was positively correlated with larger tumor volume, higher TNM stage and lymph node metastasis. Moreover, ESCC patients with high HCP5 exerted shorter survival time than patients with low HCP5. These findings uncover the importance of HCP5 in human ESCC progression; the turbulence of HCP5/YTHDF1/HK2 axis may be responsible for ESCC carcinogenicity.

Knockdown long non-coding RNA HCP5 enhances the radiosensitivity of esophageal carcinoma by modulating AKT signaling activation

Recently, long noncoding RNAs (lncRNAs) have been revealed to participate in cancer therapy. Especial in tumor radiotherapy, lncRNAs usually could enhance or restrict the radiosensitivity in different ways. LncRNA HCP5 is highly expressed in esophageal cancer and influenced the malignant behaviors of esophageal cancer cells. However, this study dedicates to clarify if lncRNA HCP5 affects the radiosensitivity of esophageal carcinoma. The expression levels of HCP5 in esophageal cancer and adjacent noncancerous tissue were first analyzed on the TCGA database and then detected by qRT-PCR. The related functional experiments were used to investigate whether the radiosensitivity of esophageal squamous cell carcinoma was affected by the inhibition of HCP5. The expression results showed HCP5 is upregulated in esophageal cancers compared to the normal tissues. Meanwhile, knockdown HCP5 further suppressed the proliferation and promoted the apoptosis of esophageal cancer cells treated with a 2 Gy dose of radiotherapy. Moreover, we uncovered that knockdown HCP5 eliminated radiotherapy resistance by modulating the miR-216a-3p/PDK1 axis to inhibit the AKT activation. Finally, rescue experiments pointed that lowering the miR-216a-3p expression weakened the inhibition effect of knockdown HCP5 on cells treated with radiotherapy. To summary, our results indicate that HCP5 is involved in esophageal carcinoma radiotherapy and knockdown HCP5 enhances the radiosensitivity of esophageal carcinoma by modulating AKT signaling activation.

LncRNA HCP5 in hBMSC-derived exosomes alleviates myocardial ischemia reperfusion injury by sponging miR-497 to activate IGF1/PI3K/AKT pathway

Ischemia/reperfusion (I/R) injury is an inevitable process during heart transplant and suppressing I/R injury could greatly improve the survival rate of recipients. Mesenchymal stem cells (MSCs) have positive effects on I/R. We aimed to investigate the mechanisms underlying the protective roles of MSCs in I/R. Both cell model and rat model of myocardial I/R were used. MTT assay and flow cytometry were used to measure cell viability and apoptosis, respectively. QRT-PCR and western blotting were employed to measure levels of lncRNA HCP5 (HLA complex P5), miR-497, apoptosis-related proteins, and insulin-like growth factor (IGF1)/PI3K/AKT pathway. Dual luciferase assay was used to validate interactions of HCP5 and miR-497, miR-497 and IGF1. Echocardiography was performed to evaluate cardiac function of rats. Serum levels of CK-MB and LDH were measured. H&E and Masson staining were used to examine morphology of myocardial tissues. hBMSC-derived exosomes (hBMSC-Exos) increased the viability of cardiomyocytes following hypoxia/reperfusion (H/R) and decreased apoptosis. H/R diminished HCP5 expression in cardiomyocytes while hBMSC-Exos recovered the level. Overexpression of HCP5 in hBMSC-Exos further enhanced the protective effects in H/R while HCP5 knockdown suppressed. HCP5 directly bound miR-497 and miR-497 targeted IGF1. miR-497 mimics or si-IGF1 blocked the effects of HCP5 overexpression. Further, hBMSC-Exos alleviated I/R injury in vivo and knockdown of HCP5 in hBMSC-Exos decreased the beneficial effects. AntagomiR-497 blocked the effects of HCP5 knockdown. HCP5 from hBMSC-Exos protects cardiomyocytes against I/R injury via sponging miR-497 to disinhibit IGF1/PI3K/AKT pathway. These results shed light on mechanisms underlying the protective role of hBMSC-Exos in I/R.

LncRNA HCP5 promotes malignant cell behaviors in esophageal squamous cell carcinoma via the PI3K/AKT/mTOR signaling

The role of lncRNA HCP5 in esophageal squamous cell carcinoma (ESCC) remains unknown despite its involvement in different malignancies. MTT assay, EdU assay, TUNEL assay, transwell assay, and sphere formation assay were conducted to reveal ESCC cell viability, proliferation, apoptosis, migration, invasion, and stemness characteristics. FISH and subcellular fraction assays were performed to reveal the subcellular location of HCP5 in ESCC cells. Luciferase reporter assay and RIP assay were conducted to explore the downstream axis of HCP5. Our findings revealed that HCP5 expression was at a higher level in ESCC tissues and cells compared to that in control tissues and cells. Additionally, HCP5 promoted ESCC cellular activities by promoting proliferation, migration, invasion ability and stemness characteristics of ESCC cells as well as suppressing cell apoptosis. Furthermore, we found that HCP5 bound with miR-139-5p to upregulate PDE4A via the competing endogenous RNA network in ESCC cells. Importantly, HCP5 was discovered to stimulate the PI3K/AKT/mTOR signaling by regulating the downstream target genes. Finally, rescue assays indicated that HCP5 promoted ESCC cell growth by activating the PDE4A-medaited PI3K/AKT/mTOR pathway. HCP5 promotes ESCC cellular development by modulating the miR-139-5p/PDE4A pathway and stimulating the PI3K/AKT/mTOR signaling pathway, which may be conducive for the improvement of ESCC treatment.

HCP5, as the sponge of miR-1291, facilitates AML cell proliferation and restrains apoptosis via increasing PIK3R5 expression

Background

Acute myeloid leukemia (AML) is recognized as a hematological neoplasm with heterogenetic cytology and short-term outcome. HCP5 has been proven to be related with the pathogenesis of AML. However, the underlying mechanism of HCP5 in AML remains unclear.

Methods

Clinical profiles of AML patients were downloaded from TCGA and GTEx databases. LncBase and TargetScan online tools were utilized to predict potential targets, and dual-luciferase reporter assay was performed to verify the association between miR-1291 and HCP5 or PIK3R5. Cell Counting Kit 8 and flow cytometry tests were implemented to evaluate the effects of HCP5/miR-1291/PIK3R5 axis in AML cells. Quantitative RT-PCR and Western blot were conducted to detect the expression levels of genes.

Results

HCP5 and PIK3R5 were significantly increased in AML tissue samples compared with healthy controls. HCP5 facilitated AML cells viability and inhibited apoptosis. There was a positive relationship between HCP5 and PIK3R5, but miR-1291 negatively regulated PIK3R5. Overexpression of PIK3R5 enhanced the promoting effect of HCP5 in the development of AML, while weakened the suppression of miR-1291 to AML progression.

Conclusion

Our findings manifested that HCP5 was remarkably upregulated in AML and upregulated HCP5 promoted the malignant behaviors of AML cells by mediating miR-1291/PIK3R5 axis, which would provide a new insight for the treatment of AML.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40246-021-00340-5.

LncRNA HCP5 knockdown inhibits high glucose-induced excessive proliferation, fibrosis and inflammation of human glomerular mesangial cells by regulating the miR-93-5p/HMGA2 axis

BACKGROUND

Long non-coding RNAs (lncRNAs) are widely reported to be involved in the development of human diseases. HLA complex P5 (HCP5) deregulation is associated with various diseases. However, the function of HCP5 in diabetic nephropathy (DN) is unclear.

METHODS

Human glomerular mesangial cells (HGMCs) were treated with high glucose (HG) to establish DN cell models. The expression of HCP5, miR-93-5p and high mobility group AT-hook 2 (HMGA2) mRNA was detected using quantitative polymerase chain reaction (QPCR). Cell proliferation and cell apoptosis were assessed using cell counting kit-8 (CCK-8) assay and flow cytometry assay, respectively. The expression of apoptosis- and fibrosis-related proteins and HMGA2 protein was quantified by western blot. The release of pro-inflammatory factor was checked using enzyme-linked immunosorbent assay (ELISA). The predicted relationship between miR-93-5p and HCP5 or HMGA2 was verified using dual-luciferase reporter assay, pull-down assay or RNA immunoprecipitation (RIP) assay.

RESULTS

The expression of HCP5 and HMGA2 was enhanced, while the expression of miR-93-5p was declined in DN serum samples and HG-treated HGMCs. HCP5 knockdown or miR-93-5p restoration ameliorated HG-induced HGMC proliferation, fibrosis and inflammation. MiR-93-5p was a target of HCP5, and miR-93-5p inhibition reversed the effects caused by HCP5 knockdown. Moreover, HMGA2 was a target of miR-93-5p, and HMGA2 overexpression abolished the effects of miR-93-5p restoration. HCP5 knockdown inhibited the AKT/mTOR signaling pathway.

CONCLUSION

HCP5 was implicated in DN progression by modulating the miR-93-5p/HMGA2 axis, which provided new insights into the understanding of DN pathogenesis.

LncRNA HCP5 : A Potential Biomarker for Diagnosing Gastric Cancer

Background

It has been reported that long non-coding RNAs (lncRNAs) can be regarded as a biomarker and had particular clinical significance for early screening and gastric cancer (GC) diagnosis. Therefore, this study aimed to investigate whether serum HCP5 could be a new diagnostic biomarker.

Methods

Filtered out the HCP5 from the GEO database. The specificity of HCP5 was verified by real-time fluorescence quantitative PCR (qRT-PCR), and then the stability of HCP5 was verified by room temperature storage and repeated freeze-thaw experiments. Meanwhile, the accuracy of HCP5 was verified by agarose gel electrophoresis (AGE) and Sanger sequencing. Simultaneously, the expression level of serum HCP5 was detected by qRT-PCR in 98 patients with primary gastric cancer, 21 gastritis patients, 82 healthy donors, and multiple cancer types. Then, the methodology analysis was carried on. Moreover, receiver operating characteristic (ROC) was used to evaluate its diagnostic efficiency.

Results

qRT-PCR method had good repeatability and stability in detecting HCP5. The expression level of HCP5 in the serum of gastric cancer patients was remarkably higher than that of healthy controls, and it could distinguish gastritis patients from healthy donors. Besides, the expression of HCP5 was increased dramatically in MKN-45 and MGC-803. The FISH assay showed that HCP5 was mainly distributed in the cytoplasm of MKN-45 and BGC-823 cells. When HCP5 was combined with existing tumor markers, the diagnostic efficiency of HCP5 was the best, and the combined diagnosis of carcinoembryonic antigen (CEA), carbohydrate antigen199 (CA199), and HCP5 can significantly improve the diagnostic sensitivity. Besides, compared with the expression levels of thyroid cancer (THCA), colorectal cancer (CRC), and breast cancer (BRCA), serum HCP5 in gastric cancer was the most specific. Moreover, the high expression of serum HCP5 was related to differentiation, lymph node metastasis, and nerve invasion. The term of serum HCP5 after the operation was significantly lower than that of patients with primary gastric cancer.

Conclusion

Serum HCP5 can be used as a potential biomarker of non-invasive fluid biopsy, which had a unique value in the early diagnosis, development, and prognosis of gastric cancer.

MEF2A-mediated lncRNA HCP5 Inhibits Gastric Cancer Progression via MiR-106b-5p/p21 Axis

Background: Long non-coding RNAs (lncRNAs) are deemed to be relevant to the tumorigenesis and development of a variety of tumors, containing gastric cancer (GC). The purpose of our investigations is to explore the character of HCP5 in GC.

Methods: HCP5 expression was detected by quantitative real-time polymerase chain reaction (qRT-PCR) in 62 matched GC tissues and corresponding para-carcinoma tissues. In vitro and in vivo functional assays were subjected to verify the biological effects of HCP5 after alteration of HCP5. Chromatin immunoprecipitation assay (CHIP) assays were conducted to confirm that myocyte enhancer factor 2A (MEF2A) could bind to HCP5 promoter regions and thereby induce HCP5 expression. Analysis of the latent binding of miR-106b-5p to HCP5 and p21 was made by bioinformatics prediction and luciferase reporter assays.

Results: Significant downregulation of HCP5 was detected in GC tissues. Negative correlation was determined between HCP5 expression level and tumor size and overall survival in GC patients. HCP5 depletion had a facilitating impact on proliferation, migration and invasion of GC cells. Consistently, overexpression of HCP5 came into an opposite effect. Moreover, we demonstrated that MEF2A could combine with the promoter region of HCP5 and thereby induce HCP5 transcription. Luciferase reporter assays revealed that HCP5 could compete with miR-106b-5p as a competing endogenous RNA (ceRNA) and upregulated p21 expression in GC.

Conclusions: MEF2A-mediated HCP5 could exert an anti-tumor effect among the development of GC via miR-106b-5p/p21 axis, which provides a novel target for GC therapy.

Effects of LncRNA HCP5/miR-214-3p/MAPK1 Molecular Network on Renal Cell Carcinoma Cells

Background

Recent researches have shown that long non-coding RNA (LncRNA) is often disordered and acts in many carcinomas. Clear cell renal cell carcinoma (ccRCC) is the main reason for carcinoma-related deaths, which are mainly caused by the metastasis. HCP5 is a newly discovered LcnRNA. Early studies have found that HCP5 acts in neoplasm metastasis, but the mechanism of HCP5 in ccRCC is still unclear.

Methods

The expression of HCP5 in human renal cell carcinoma (RCC) was detected by real-time quantitative PCR. The biological effect of LncRNAs in proliferation, migration, invasion and metastasis of RCC cells was explored by gain-of-function and loss-of-function tests. The molecular mechanism of LncRNAs was explored by RNA immunoprecipitation and Western blot.

Results

qRT-PCR revealed that HCP5 was enhanced in neoplasm tissues of ccRCC patients and correlated with the metastatic characteristics of RCC. Over-expression of HCP5 promoted the proliferation, migration and invasion of renal carcinoma cells. The deletion of HCP5 inhibited the proliferation, migration and invasion of RCC in vitro and the metastasis of RCC in vivo. Mechanically, HCP5 inhibited the growth and metastasis of ccRCC cells by regulating miR-214-3p/MAPK1 axis.

Conclusion

HCP5, as a key LncRNA, can promote ccRCC metastasis by regulating miR-214-3p/MAPK1 axis and may be a biomarker and be helpful for judging the prognosis of ccRCC.

T Cell Factor 4 Is Involved in Papillary Thyroid Carcinoma via Regulating Long Non-Coding RNA HCP5

The annual incidence of papillary thyroid carcinoma has increased dramatically. T cell factor 4 (TCF4) is an important component of Wnt signaling pathway.However, the role of TCF4 in PTC remains unknown. In this study, TCF4 was observed to overexpress in PTC patients and cells by qRT-PCR assay. The colony formation assay, Edu staining and transwell assay indicated thatoverexpression of TCF4 promoted cell proliferation and invasion of TCP-1 cells, whereas knockdown of TCF4 inhibited cell proliferation and invasion of IHH-4 cells. To investigate the mechanism of TCF4 in PTC cells, the luciferase assay demonstrated that TCF4 could modulate HCP5 expression. Besides, GLuc-ON promoter reporter assayproved that TCF4 could bind to HCP5 promoter. Further, knockdown of HCP5 could significantly up-regulated miR-15a, miR-216a-5p, miR-22-3p, miR-139-5p, miR-203, miR-27a-3p and miR-320, and down-regulated miR-186-5p in IHH-4 cells, which might be potential downstream of TFC4/HCP5 axis. In conclusion, up-regulation TCF4 can promote HCP5 expression via binding to HCP5 promoter. It may be the first time to prove that TCF4 regulates HCP5 in PTC, which provides a novel sight for treatment of PTC.

Long non-coding RNA HCP5 in cancer

Cancer remains a major threat to human health worldwide. Long non-coding RNA (lncRNA) comprises a group of single-stranded RNA with lengths longer than 200 bp. LncRNAs are aberrantly expressed and play a variety of roles involving multiple cellular processes in cancer. Histocompatibility leukocyte antigen complex P5 (HCP5), initially reported in 1993, is an important lncRNA located between the MICA and MICB genes in MHC I region. HCP5 is involved many autoimmune diseases as well as malignancies. Abnormal HCP5 expression occurs in many types of cancer and its dysregulation appears closely associated with tumor progression. HCP5 is also involved in anti-tumor drug resistance as well. As such, HCP5 represents a promising biomarker and therapeutic target in cancer. In this review, we summarize recent researches and provide an overview of the role and mechanism of HCP5 in human cancer.

Knockdown of lncRNA HCP5 protects against cerebral ischemia/reperfusion injury by regulating miR-652-3p

Previous studies have shown that lncRNAs play crucial roles in cerebral ischemia/reperfusion injury. In this study, the function and possible mechanism of lncRNA HCP5 in cerebral ischemia/reperfusion injury was investigated. An oxygen glucose deprivation (OGD) model in N2a cells was used to simulate cerebral ischemia/reperfusion injury in vitro. The functional mechanism of lncRNA HCP5 was detected using Trypan blue staining, JC-1, MTT and dual luciferase reporter assays. The expression of apoptosis-related proteins (Bcl-2 and Bax) was measured by Western blot analysis. We found that lncRNA HCP5 was upregulated in N2a cells treated with OGD/R, and knockdown of lncRNA HCP5 enhanced cell viability and reduced cell death. In addition, miR-652-3p was found to act as a sponge for lncRNA HCP5. The overexpression of miR- 652-3p can prevent cerebral ischemic reperfusion injury, however, lncRNA HCP5 attenuated the protective effect of miR-652-3p in cerebral ischemic reperfusion injury. In conclusion, upregulation of lncRNA HCP5 may exacerbate cerebral ischemic reperfusion injury by sponging miR-652-3p.

LncRNA HCP5 Regulates Pancreatic Cancer Progression by miR-140-5p/CDK8 Axis

Background: Pancreatic cancer (PC) is a leading cause of cancer-related deaths worldwide. Human leukocyte antigen complex P5 (HCP5), a member of long noncoding RNAs (lncRNAs), was reported to be associated with the poor prognosis of PC. However, the mechanism of HCP5 in regulating the progression of PC remains poorly defined. Materials and Methods: Quantitative real-time polymerase chain reaction was performed to detect the expression levels of HCP5, microRNA (miR)-140-5p, and cyclin-dependent kinase 8 (CDK8) in PC tissues and cells. Cell counting kit-8 (CCK-8) assay was utilized to check cell proliferation. Transwell assay was employed to evaluate the abilities of cell migration and invasion. Xenograft tumor model was established to investigate the biological role of HCP5 in PC in vivo. The interaction between miR-140-5p and HCP5 or CDK8 was predicted by starBase or TargetScan, respectively. The dual-luciferase reporter assay was conducted to corroborate the interaction. The protein level of CDK8 was measured by Western blot. Results: HCP5 and CDK8 were significantly upregulated in PC tissues and cells, opposite to the expression of miR-140-5p. High expression of HCP5 contributed to the low survival rate and HCP5 silencing inhibited proliferation, migration, and invasion of PC cells in vitro. Simultaneously, in vivo experiments indicated that downregulation of HCP5 suppressed tumor growth. In addition, miR-140-5p was a target of HCP5 and bound to the 3'-untranslated region (3'UTR) of CDK8. Further studies revealed that overexpression of CDK8 reversed the miR-140-5p-mediated inhibitory effect on PC progression. Moreover, downregulation of miR-140-5p or upregulation of CDK8 inverted the silencing-mediated repressive impact of HCP5 on PC progression. Conclusion: Downregulation of HCP5 impeded PC progression by downregulating CDK8 via sponging miR-140-5p.

Gene expression of indoleamine and tryptophan dioxygenases and three long non-coding RNAs in breast cancer

The kynurenine pathway (KP) has a principal role in the metabolism of tryptophan. This pathway is also involved in the pathogenesis of cancer. We evaluated expression of two rate limiting enzymes from this pathway (IDO1 and TDO2) as well as three long non-coding RNAs (lncRNAs) that have been predicted to alter expression of IDO1 (ITGB2-AS1, HCP5 and MIR155HG) in 82 breast cancer tissues and their adjacent non-cancerous tissues (ANCTs). While IDO1 expression levels were not significantly different between malignant tissues and ANCTs (expression ratio = 0.56, P = .21), TDO2 was significantly down-regulated in malignant tissues compared with ANCTs (Expression ratio = 0.001, P < .001). Among lncRNAs, expression of HCP5 was significantly lower in malignant tissues compared with ANCTs (Expression ratio = 0.17, P < .001). However, expression of ITGB2-AS1 was higher in malignant tissues compared with ANCTs (Expression ratio = 3.38, P = .01). Expressions of genes were not associated with any of clinical or demographic data of patients. However, there were trends towards association between IDO1 expression and tumor size as well as estrogen receptor (ER) status (P values 0.09 and 0.08 respectively). Significant pairwise correlations were found between expression levels of genes especially in ANCTs. Notably, TDO2 expression levels were correlated with expression of all other genes in ANCTs but none of them in tumor tissues. Based on the area under curve (AUC) values, HCP5 and TDO2 had "fair" diagnostic power (AUC values of 0.73 and 0.72). Notably, combination of HCP5, ITGB2-AS1 and TDO2 genes increased the diagnostic power to the level of "good". The current investigation underscores the role of KP in breast cancer and potentiates some genes within this pathway as diagnostic markers in breast cancer.

LncRNA HCP5 Stimulates the Proliferation of Non-Small Cell Lung Cancer Cells by Up-Regulating Survivin Through the Down-Regulation of miR-320

Introduction

We explored the roles of lncRNA HCP5 in non-small cell lung cancer (NSCLC).

Methods

Levels of HCP5 were measured by performing qPCR and data were compared between non-tumor and NSCLC tissue samples by performing a paired t-test. Expression levels of miR-320 and survivin mRNA in NSCLC tissues were also measured by performing qPCR. The effects of HCP5, miR-320 and survivin overexpression on the proliferation of H23 cells were analyzed by cell proliferation assay.

Results

We found that HCP5 was up-regulated in NSCLC and predicted the poor survival of NSCLC patients. HCP5 was negatively correlated with miR-320 but positively correlated with survivin in NSCLC tissues. In NSCLC cells, HCP5 overexpression led to the up-regulated survivin and down-regulated miR-320. Moreover, miR-320 overexpression failed to affect HCP5 but down-regulated survivin. Cell proliferation assay showed that HCP5 and survivin overexpression led to increased, while miR-320 overexpression led to decreased cell proliferation rate. In addition, miR-320 overexpression reduced the effects of HCP5 overexpression.

Conclusion

Therefore, HCP5 may stimulate the proliferation of NSCLC cells by up-regulating survivin through the down-regulation of miR-320.

Geniposide inhibits proliferation and induces apoptosis of diffuse large B-cell lymphoma cells by inactivating the HCP5/miR-27b-3p/MET axis

Diffuse large B-cell lymphoma (DLBCL) is commonly treated with R-CHOP, but ~30 to 50% of the patients are poorly responsive to this strategy. Geniposide, an extract from the Gardenia jasminoides Ellis, plays antitumor roles in human gastric cancer, hepatocellular carcinoma, and oral squamous carcinoma. However, the effects of geniposide treatment on DLBCL cells, as well as its underlying mechanism, are still unknown. Here, we found that geniposide inhibited the proliferation of OCI-LY7 and OCI-LY3 cells in a dose-dependent manner. Furthermore, geniposide increased the percentage of apoptotic cells and upregulated the levels of cleaved PARP and cleaved caspase-3 in DLBCL cells. Interestingly, geniposide treatment significantly reduced the expression of the long noncoding RNA HLA complex P5 (lncRNA HCP5) in DLBCL cells. HCP5 expression was revealed to be upregulated in DLBCL tissues and cell lines. Moreover, HCP5 knockdown resulted in proliferation inhibition and apoptosis in OCI-LY7 and OCI-LY3 cells. miR-27b-3p was predicted as a potential target of HCP5 using the lnCAR web tool. Both HCP5 silencing and geniposide treatment increased the level of miR-27b-3p in DLBCL cells. Accordingly, a luciferase reporter assay identified miR-27b-3p as a direct target of HCP5. The expression of miR-27b-3p was upregulated and inversely correlated with the HCP5 level in DLBCL tissues. HCP5 knockdown reduced MET protein expression, which was subsequently rescued by miR-27b-3p silencing in DLBCL cells. Importantly, the restoration of MET partially reversed the geniposide-induced proliferation inhibition and apoptosis of DLBCL cells. In conclusion, geniposide inhibits the proliferation and induces the apoptosis of DLBCL cells at least partially by regulating the HCP5/miR-27b-3p/MET axis, indicating a potential strategy for DLBCL treatment.

LncRNA HCP5 promotes LAML progression via PSMB8-mediated PI3K/AKT pathway activation

Acute myeloid leukemia is an aggressive myeloid malignancy, characterized by rapid cellular proliferation and generally high mortality. Due to the lack of a complete understanding of AML, its clinical outcomes are still not satisfactory. In this study, we examined the function of the long non-coding RNA-HLA complex P5 (HCP5) on AML by analyzing the clinical samples, TCGA data, and by shRNA-mediated HCP5 deficiency in vitro. Our results showed that HCP5 is highly expressed in AML and is positive associated with poor prognosis, and HCP5 knockdown was significantly suppressing AML cell line proliferation and inducing G1/S arrest in vitro. In mechanism, the proteasome subunit beta type 8 (PSMB8) expression was dramatically inhibited in HCP5 knockdown cells while increased in HCP5 overexpression cells. PSMB8 was also highly expressed in AML and with poor prognosis. Furthermore, HCP5 regulates PI3K/AKT pathway activation depending on PSMB8. Our results showed a promoting function of HCP5 on AML and may provide a compelling biomarker and therapy target for AML.

Long noncoding RNA HCP5 suppresses skin cutaneous melanoma development by regulating RARRES3 gene expression via sponging miR-12

Objective

This research aimed to investigate the role and mechanism of long noncoding RNA (lncRNA) HCP5 in skin cutaneous melanoma (SKCM).

Materials and methods

Survival analysis was performed using The Cancer Genome Atlas (TCGA)-SKCM data and SKCM patients’ clinical data. Primary SKCM cells were derived from patients’ pathologic tissue specimens. HCP5 overexpression was achieved by lentiviral transduction. Malignancy of SKCM cells was evaluated in vitro by cell proliferation, colony formation, apoptosis and transwell invasion assays. RARRES3 knockdown was achieved by siRNA transfection. DIANA microT-CDS algorithm was used to predict miRNAs that might interact with HCP5 and 3ʹ untranslated region of RARRES3 mRNA. microRNA target luciferase reporter assay and AGO2-RNA immunoprecipitation were used to verify the interaction between HCP5, 3ʹ UTR of RARRES3 mRNA and miR-1286.

Results

HCP5 level was decreased in SKCM tissue specimens compared to noncancerous counterparts. Low expression of HCP5 was associated with SKCM patients’ poor overall survival and disease progression. HCP5 overexpression significantly reduced the malignancy of primary SKCM cells in vitro. RARRES3 was found as a HCP5-co-expressing gene in SKCM cells. HCP5 overexpression significantly increased RARRES3 expression in SKCM cells. RARRES3 knockdown partially abolished the anti-SKCM effect of HCP5 overexpression. MiR-1286 was found interacting with both HCP5 and 3ʹ UTR of RARRES3 mRNA.

Conclusion

HCP5 is a cancer-suppressive lncRNA in SKCM. HCP5 overexpression decreased SKCM cell malignancy in vitro by upregulating RARRES3, possibly via sponging miR-1286.

LncRNA HCP5 promotes triple negative breast cancer progression as a ceRNA to regulate BIRC3 by sponging miR-219a-5p

Emerging evidence has suggested that long noncoding RNAs (lncRNA) involved in the development and progression of cancer. Triple negative breast cancer (TNBC) was an aggressive type of breast cancer with high rates of cancer recurrence and metastasis. The pathogenesis of TNBC is largely unknown. Recent studies suggested that lncRNA HCP5 plays an important role in carcinogenesis. The purpose of this study was to examine the function and mechanism of HCP5 in TNBC. We observed that HCP5 was upregulated in TNBC cell lines and specimens. HCP5 knockdown induced TNBC cell apoptosis, and inhibited cell proliferation and orthotopic xenograft tumor growth. RNA sequencing and antibody array suggested that HCP5 achieves its functions through regulating apoptosis pathway. Bioinformatics, luciferase and RIP experiments proved that both HCP5 and BIRC3 could competitively bind to miR‐219a‐5p. Increased BIRC3 and decreased miR‐219a‐5p were observed in TNBC tissues and cell lines. We then performed gain‐ and loss‐of‐function studies as well as rescue experiments in TNBC cells. The decrease of proliferation and migration due to HCP5 knockdown could be rescued when miR‐219a‐5p inhibitor or BIRC3 was transfected and vice versa. Our study suggested that lncRNA HCP5 promotes TNBC progression as a ceRNA to regulate BIRC3 by sponging miR‐219a‐5p. In a word, we revealed a new signaling pathway to mediate TNBC, and provided HCP5 as a new target for improving treatment of TNBC.

Long Noncoding RNA HCP5, a Hybrid HLA Class I Endogenous Retroviral Gene: Structure, Expression, and Disease Associations

The HCP5 RNA gene (NCBI ID: 10866) is located centromeric of the HLA-B gene and between the MICA and MICB genes within the major histocompatibility complex (MHC) class I region. It is a human species-specific gene that codes for a long noncoding RNA (lncRNA), composed mostly of an ancient ancestral endogenous antisense 3′ long terminal repeat (LTR, and part of the internal pol antisense sequence of endogenous retrovirus (ERV) type 16 linked to a human leukocyte antigen (HLA) class I promoter and leader sequence at the 5′-end. Since its discovery in 1993, many disease association and gene expression studies have shown that HCP5 is a regulatory lncRNA involved in adaptive and innate immune responses and associated with the promotion of some autoimmune diseases and cancers. The gene sequence acts as a genomic anchor point for binding transcription factors, enhancers, and chromatin remodeling enzymes in the regulation of transcription and chromatin folding. The HCP5 antisense retroviral transcript also interacts with regulatory microRNA and immune and cellular checkpoints in cancers suggesting its potential as a drug target for novel antitumor therapeutics.

HCP5 is a SMAD3-responsive long non-coding RNA that promotes lung adenocarcinoma metastasis via miR-203/SNAI axis

Introduction: Transforming growth factor-beta (TGFβ) signaling plays a vital role in lung adenocarcinoma (LUAD) progression. However, the involvement of TGFβ-regulated long non-coding RNAs (lncRNAs) in metastasis of LUAD remains poorly understood.

Methods: We performed bioinformatic analyses to identify putative lncRNAs regulated by TGF-β/SMAD3 and validated the results by quantitative PCR in LUAD cells. We performed luciferase reporter and chromatin immunoprecipitation assays to demonstrate the transcriptional regulation of the lncRNA histocompatibility leukocyte antigen complex P5 (HCP5) we decided to focus on. Stable HCP5 knockdown and HCP5-overexpressing A549 cell variants were generated respectively, to study HCP5 function and understand its mechanism of action. We also confirmed our findings in mouse xenografts and metastasis models. We analyzed the correlation between the level of lncRNA expression with EGFR, KRAS mutations, smoke state and prognostic of LUAD patients.

Results: We found that the lncRNA HCP5 is induced by TGFβ and transcriptionally regulated by SMAD3, which promotes LUAD tumor growth and metastasis. Moreover, HCP5 is overexpressed in tumor tissues of patients with LUAD, specifically in patients with EGFR and KRAS mutations and current smoker. HCP5 high expression level is positively correlated with poor prognosis of patients with LUAD. Finally, we demonstrated that upregulation of HCP5 increases the expression of Snail and Slug by sponging the microRNA-203 (miR-203) and promoting epithelial-mesenchymal transition (EMT) in LUAD cells.

Conclusions: Our work demonstrates that the lncRNA HCP5 is transcriptionally regulated by SMAD3 and acts as a new regulator in the TGFβ/SMAD signaling pathway. Therefore, HCP5 can serve as a potential therapeutic target in LUAD.

Paediatric-onset and adult-onset Graves' disease share multiple genetic risk factors

BACKGROUND

Graves' disease (GD) is an autoimmune thyroid disease (AITD) with a peak incidence between 30 and 50 years of age. Although children and adolescents may also develop the disease, the genetic background of paediatric-onset GD (POGD) remains largely unknown. Here, we looked for similarities and differences in the genetic risk factors for POGD and adult-onset GD (AOGD) as well as for variants associated with age of GD onset.

MATERIALS AND METHODS

A total of 1267 GD patients and 1054 healthy controls were included in the study. Allele frequencies of 40 established and suggested GD/AITD genetic risk variants (39 SNPs and HLA-DRB1*03) were compared between POGD (N = 179), AOGD (N = 1088) and healthy controls. Subsequently, multiple linear regression was used to explore the relationship between age of GD onset and genotype for each locus.

RESULTS

We identified six POGD risk loci, all of them were also strongly associated with AOGD. Although for some of the analysed variants, including HCP5 (rs3094228), PRICKLE1 (rs4768412) and SCGB3A2 (rs1368408), allele frequencies differed nominally between POGD and AOGD patients, these differences were not significant after applying multiple testing correction (P_cor  = 0.05/40 = 1.25 × 10^-3 ). Regression analysis showed that patients with higher number of HCP5 risk alleles tend to have a significantly earlier onset of GD (P = 6.9 × 10^-5 ).

CONCLUSIONS

The results of our study revealed that POGD and AOGD share multiple common genetic risk variants. Moreover, we demonstrated for the first time that HCP5 polymorphism is associated with an earlier age of GD onset in a dose-dependent manner.

Brucella melitensis and Mycobacterium tuberculosis depict overlapping gene expression patterns induced in infected THP-1 macrophages

Pathogens infecting mammalian cells have developed various strategies to suppress and evade their hosts' defensive mechanisms. In this line, the intracellular bacteria that are able to survive and propagate within their host cells must have developed strategies to avert their host's killing attitude. Studying the interface of host-pathogen confrontation can provide valuable information for defining therapeutic approaches. Brucellosis, caused by the Brucella strains, is a zoonotic bacterial disease that affects thousands of humans and animals around the world inflicting discomfort and huge economic losses. Similar to many other intracellular dwelling bacteria, infections caused by Brucella are difficult to treat, and hence any attempt at identifying new and common therapeutic targets would prove beneficial for the purpose of curing infections caused by the intracellular bacteria. In THP-1 macrophage infected with Brucella melitensis we studied the expression levels of four host's genes, i.e. EMP2, ST8SIA4, HCP5 and FRMD5 known to be involved in pathogenesis of Mycobacterium tuberculosis. Our data showed that at this molecular level, except for FRMD5 that was downregulated, the other three genes were upregulated by B. melitensis. Brucella melitensis and M. tuberculosis go through similar intracellular processes and interestingly two of the investigated genes, i.e. EMP2 and ST4SIA8 were upregulated in THP-1 cell infected with B. melitensis similar to that reported for THP-1 cells infected with M. tuberculosis. At the host-pathogen interaction interface, this study depicts overlapping changes for different bacteria with common survival strategies; a fact that implies designing therapeutic approaches based on common targets may be possible.

Comparative genetic analyses point to HCP5 as susceptibility locus for HCV-associated hepatocellular carcinoma

BACKGROUND & AIMS

Recently, genetic variations in MICA (lead single nucleotide polymorphism [SNP] rs2596542) were identified by a genome-wide association study (GWAS) to be associated with hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC) in Japanese patients. In the present study, we sought to determine whether this SNP is predictive of HCC development in the Caucasian population as well.

METHODS

An extended region around rs2596542 was genotyped in 1924 HCV-infected patients from the Swiss Hepatitis C Cohort Study (SCCS). Pair-wise correlation between key SNPs was calculated both in the Japanese and European populations (HapMap3: CEU and JPT).

RESULTS

To our surprise, the minor allele A of rs2596542 in proximity of MICA appeared to have a protective impact on HCC development in Caucasians, which represents an inverse association as compared to the one observed in the Japanese population. Detailed fine-mapping analyses revealed a new SNP in HCP5 (rs2244546) upstream of MICA as strong predictor of HCV-related HCC in the SCCS (univariable p=0.027; multivariable p=0.0002, odds ratio=3.96, 95% confidence interval=1.90-8.27). This newly identified SNP had a similarly directed effect on HCC in both Caucasian and Japanese populations, suggesting that rs2244546 may better tag a putative true variant than the originally identified SNPs.

CONCLUSIONS

Our data confirms the MICA/HCP5 region as susceptibility locus for HCV-related HCC and identifies rs2244546 in HCP5 as a novel tagging SNP. In addition, our data exemplify the need for conducting meta-analyses of cohorts of different ethnicities in order to fine map GWAS signals.