Exosomal microRNAs as potential circulating biomarkers in gastrointestinal tract cancers: a systematic review protocol

Circulating exosomal microRNAs as potential prognostic biomarkers in gastrointestinal cancers: a systematic review and meta-analysis

BACKGROUND

Recent reports suggested that circulating exosomal microRNAs (exomiRs) may serve as non-invasive prediction biomarkers in gastrointestinal (GI) cancers, yet their clinicopathological and prognostic values need to be more clarified. Hence, the present meta-analysis was aimed to quantitatively assess the evidence regarding the association between circulating exomiRs and prognosis in GI cancer patients.

METHODS

A comprehensive search was carried out in prominent literature databases, including PubMed, ISI Web of Science, Scopus, and Embase. Odds ratios (ORs) or hazard ratios (HRs) with 95% confidence intervals (CIs) were gathered to evaluate the strength of the association. The quality assessment was investigated through the Newcastle-Ottawa Scale (NOS) and publication bias via Eggers' test and funnel plots.

RESULTS

A total of 47 studies, comprising of 4881 patients, were considered eligible for this meta-analysis. Both up-regulated and down-regulated circulating exomiRs are significantly associated with differentiation (HR = 1.353, P = 0.015; HR = 1.504, P = 0.016), TNM stage (HR = 2.058, P < 0.001; HR = 2.745, P < 0.001), lymph node metastasis (HR = 1.527, P = 0.004; HR = 2.009, P = 0.002), distant metastasis (HR = 2.006, P < 0.001; HR = 2.799, P = 0.002), worse overall survival (OS) (HR = 2.053, P < 0.001; HR = 1.789, P = 0.001) and poorer disease/relapse/progression-free survival (DFS/RFS/PFS) (HR = 2.086, P < 0.001; HR = 1.607, P = 0.001) in GI cancer patients, respectively. In addition, subgroup analyses based on seven subcategories indicated the robustness of the association. The majority of findings were lack of publication bias except for the association between up-regulated exomiRs and OS or DFS/RFS/PFS and for the down-regulated exomiRs and TNM stage.

CONCLUSION

This study supports that up- and down-regulated circulating exomiRs are associated with poorer survival outcomes and could be served as potential prognostic biomarkers in GI cancers. Given the limitations of the current findings, such as significant heterogeneity, more investigations are needed to fully clarify the exomiRs prognostic role.

Colorectal cancer cell-derived extracellular vesicles transfer miR-221-3p to promote endothelial cell angiogenesis via targeting suppressor of cytokine signaling 3

BACKGROUND

Secreted microRNAs (miRNAs) can serve as promising diagnostic markers for colorectal cancer (CRC). Herein, we evaluated the potential clinical significance of a signature of four circulating serum-derived miRNAs in CRC. We also demonstrated that extracellular vesicles (EVs) containing miR-221-3p could facilitate endothelial cell angiogenesis.

METHODS

The expressions of four circulating serum-derived miRNAs (miR-19a-3p, miR-203-3p, miR-221-3p, and let-7f-5p) were measured by real-time quantitative PCR, and their associations with lymph node metastasis were determined in CRC patients. Receiver operating characteristic curve analysis was used to determine their diagnostic accuracy. EVs were isolated and characterized from the conditioned media of human CRC cells (HCT116 and Caco2). Cell proliferation, transwell migration, and tube formation assays were performed to investigate the pro-angiogenic effect of miR-221-3p transferred by CRC-EVs into the endothelial cells. In silico analysis was used to show the regulatory functions of miR-221-3p on SOCS3, validated by luciferase and Western blotting assays.

RESULTS

The expression levels of serum-derived miR-19a-3p, miR-203-3p, miR-221-3p, and let-7f-5p were significantly higher in CRC than in healthy individuals. The expression of miR-19a-3p, miR-203-3p, and miR-221-3p were positively correlated with the lymph node metastasis status. Moreover, SOCS3 was identified as a direct target of miR-221-3p and the secreted miR-221-3p shuttled by CRC-EVs regulated STAT3/VEGFR-2 signaling axis by targeting SOCS3 in endothelial cells. CRC-EVs promoted endothelial cell proliferation, migration, and the formation of vessel-like structures. The proangiogenic effect of CRC-EVs on the cells was recapitulated by miR-221-3p overexpression, showing the importance of EVs-derived miR-221-3p in promoting endothelial cell angiogenesis.

CONCLUSION

We introduced a signature of four-circulating miRNAs (miR-19a-3p, miR-203-3p, miR-221-3p, and let-7f-5p) as a novel diagnostic biomarker for CRC. Besides, we revealed that miR-221-3p induces endothelial cell angiogenesis in vitro by targeting SOCS3.

Growth in Proportion and Disparities of HIV PrEP Use Among Key Populations Identified in the United States National Goals: Systematic Review and Meta-analysis of Published Surveys

BACKGROUND

Pre-exposure prophylaxis (PrEP) use among populations most vulnerable to HIV as identified in the national HIV prevention goals is not fully known. This systematic review assessed trends of lifetime self-reported PrEP use and disparities among key populations.

METHODS

We used the CDC HIV/AIDS Prevention Research Synthesis cumulative database of electronic and manual searches in MEDLINE, CINAHL, EMBASE, and PsycINFO from 2000 to 2019 to identify English-language primary studies reporting PrEP use. Two reviewers independently screened citations, extracted data, and assessed the risk of bias with the modified Newcastle-Ottawa Scale. We estimated pooled proportions and crude/adjusted odds ratio.

RESULTS

We identified 95 eligible studies including 95,854 US-based survey respondents. A few studies (6.3%) focused on persons who inject drugs. In 2015-2017, men who have sex with men (MSM) had highest proportion of individuals who used PrEP over their lifetime [13.9% (95% confidence interval: 8.8 to 21.1), k (number of surveys) = 49] followed by Hispanic/Latinos [11.5 (7.1 to 18.1), 12], transgender women [11.2 (5.8 to 20.6), 5], and blacks [9.9 (8.3 to 11.8), 18]. Odds of PrEP use increased by 34%/year [odds ratio = 1.34/year (95% confidence interval: 1.09 to 1.64)] and significantly increased over time among MSM [1.53/year (1.21-1.93)] and blacks [1.44 (1.13-1.83)]. People in the Southern United States [9.9 (4.7-19.7), 8] and youth [7.3 (4.7-11.2), 8] had lower rates and did not demonstrate growth [0.94 (0.29-3.18); 0.82 (0.43-1.55)]. Odds of reporting lifetime PrEP use was twice [2.07 (1.27-3.38)] as great among MSM than non-MSM.

CONCLUSIONS

Proportions of PrEP use in published surveys have been growing, but remain low for people in the Southern United States and youth, and understudied in persons who inject drugs. Limitations include few studies in certain years, whereas strengths include a large number of respondents. Culturally tailored approaches targeting vulnerable populations are essential in increasing PrEP use to reduce disparities in HIV acquisition.

Diagnostic accuracy of cerebrospinal fluid and serum-isolated extracellular vesicles for glioblastoma: a systematic review and meta-analysis

BACKGROUND

Glioblastoma (GBM) is the most malignant brain cancer because there are no available biopsy-free methods for the diagnosis or the preoperative early detection. In this regard, the development of a non- or minimally invasive methods for early detection could increase the survival rate of GBM patients.

METHODS

The present study aimed to assess the diagnostic accuracy of extracellular vesicles (EVs) derived RNAs, isolated from patients' CSF or serum for GBM diagnosis. For this purpose, we searched all literature databases and performed a backward and forward reference checking procedure to retrieve appropriate studies. We conducted a meta-analysis on EVs derived biomarkers as well as sensitivity analysis and meta-regression.

RESULTS

We identified EVs-derived 24 RNAs, which can diagnose GBM. The analyzed pooled data showed 76% sensitivity, 80% specificity, and 0.85 AUC, for 16 biomarkers. Besides, the pooled PLR, NLR, and DOR were 3.7, 0.30, and 12, respectively. Subgroup analysis did not show a significant difference between serum and CSF.

CONCLUSIONS

According to the pooled sensitivity, specificity, and AUC for EVs derived biomarkers, we suggest that EVs-derived biomarkers might serve as a high potential and noninvasive diagnostic tool for GBM detection using serum and CSF samples.

CircAKT3 inhibits glycolysis balance in lung cancer cells by regulating miR-516b-5p/STAT3 to inhibit cisplatin sensitivity

OBJECTIVE

Lung cancer was one of the most deadly cancers around the world. Circular RNA AKT3 (CircAKT3) was highly expressed in lung cancer and could inhibit cell proliferation, but there were few studies on the mechanism of specific regulation of drug resistance. Therefore, we aimed to provide new ideas and perspectives for the role of circAKT3 in the mechanism of tumor resistance.

METHODS

The levels of circAKT3, miR-516b-5p and STAT3 in lung cancer tissues and cells were examined using quantitative real-time polymerase chain reaction (qRT-PCR) or western blot assays. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay was used to examine the sensitivity of cells treated under different conditions to cisplatin (DDP). A glucose assay kit and lactate assay kit were used to assess glycolysis and lactate production of cells treated with different plasmids and 2-deoxy-glucose (2-DG). Western blot analysis was used to detect the expression level of the hypoxia-inducible factor (HIF-1α) in A549 and H1299 cells. Starbase 3.0 predicted a targeted relationship between circAKT3 and miR-516b-5p, STAT3 and miR-516b-5p, and the relationship was proved by a dual-luciferase reporter assay. Knockdown of circAKT3 was used to study the effects of circAKT3 on tumor development in vivo.

RESULTS

The levels of circAKT3 and STAT3 were upregulated, miR-516b-5p was downregulation in lung cancer tissues and cells. Functionally, circAKT3 knockdown improved cell sensitivity to DDP, and repressed glycolysis in lung cancer cells. Meanwhile, inhibition of HIF-1α-dependent glycolysis attenuated the circAKT3-induced increase of chemo-resistance in A549 cells. Mechanistically, miR-516b-5p was found to possess some binding sites with circAKT3. Noticeably, the inhibitory action of circAKT3 knockdown on DDP resistance and glycolysis was overturned through inhibitor of miR-516b-5p in lung cancer cells. Furthermore, besides, circAKT3 knockdown suppressed lung tumor cell growth by the miR-516b-5p/STAT3 axis in vivo.

CONCLUSIONS

CircAKT3 inhibit cisplatin sensitivity of lung cancer cells at least partly through regulating miR-516b-5p/STAT3 axis-mediated glycolysis balance, providing a possible long noncoding RNA -targeted therapy for lung cancer.

Circulating exosomal miRNAs in cardiovascular disease pathogenesis: New emerging hopes

Cardiovascular diseases (CVDs) are one of the leading causes of morbidity and mortality. Standard therapies have failed to significantly increase patients' survival. Moreover, the majority of conventional screening procedures are ineffective for the diagnosis of CVDs at early stages. Accumulating evidence suggests that numerous cell types release a class of nano-sized vesicles named exosomes into the extracellular space. Exosomes are widely distributed in various body fluids and contain a number of diverse biomolecules such as proteins, lipids, and both mRNA and noncoding RNAs which reflect host-cell molecular architecture. MicroRNAs (miRNAs), which can be found in exosomes, could be taken up by both neighboring and distal cells. Not only has recent evidence indicated the regulatory role of exosomal miRNAs in the pathogenesis of CVD, but it has also been shown that differential expression of exosomal miRNAs in CVDs has made them promising biomarkers for early detection of CVDs. Owing to these remarkable features, exosomal miRNAs have emerged as hot spots in research. This review summarizes the role of exosomal miRNAs in the pathogenesis of CVDs and discusses their potential application in the clinical setting as both therapeutic and diagnostic tools.

Increasing prevalence of self-reported HIV preexposure prophylaxis use in published surveys: a systematic review and meta-analysis

: When combining results from all published surveys, about one in nine global study participants (10.7%) reported ever using preexposure prophylaxis (PrEP) by 2017, a significant increase since US FDA approval in 2012 [odds ratio (OR) = 1.6/year, P < 0.00001]. Moreover, nearly one in six US-based study participants (17.3%) and nearly one in four MSM who met the Centers for Disease Control and Prevention's PrEP indications (24.5%) reported ever using PrEP by 2016. The odds of reporting PrEP use are approximately doubling each year (OR = 1.8/year, P < 0.00001; OR = 2.0/year, P < 0.00001).