miR-518f-5p decreases tetraspanin CD9 protein levels and differentially affects non-tumourigenic prostate and prostate cancer cell migration and adhesion

MiR-146a rs2910164 (G/C) polymorphism is associated with the development and prognosis of acute coronary syndromes: an observational study including case control and validation cohort

BACKGROUND

Polymorphisms in microRNAs (miRNAs) play an important role in acute coronary syndromes (ACS). The purpose of this study was to assess the association of miR-146a rs2910164 and miR-34b rs4938723 polymorphisms with the development and prognosis of ACS and to explore the underlying mechanisms.

METHODS

A case-control study of 1171 subjects was included to determine the association of miR-146a rs2910164 and miR-34b rs4938723 polymorphisms with ACS risk. An additional 612 patients with different miR-146a rs2910164 genotypes, who underwent percutaneous coronary intervention (PCI) were included in the validation cohort and followed for 14 to 60 months. The endpoint was major adverse cardiovascular events (MACE). A luciferase reporter gene assay was used to validate the interaction of oxi-miR-146a(G) with the IKBA 3'UTR. Potential mechanisms were validated using immunoblotting and immunostaining.

RESULTS

The miR-146a rs2910164 polymorphism was significantly associated with the risk of ACS (Dominant model: CG + GG vs. CC, OR = 1.270, 95% CI (1.000-1.613), P = 0.049; Recessive model: GG vs. CC + CG, OR = 1.402, 95% CI (1.017-1.934), P = 0.039). Serum inflammatory factor levels were higher in patients with the miR-146a rs2910164 G allele than in those with the C allele. MiR-146a rs2910164 polymorphism in dominant model was associated with the incidence of MACE in post-PCI patients (CG + GG vs. CC, HR = 1.405, 95% CI (1.018-1.939), P = 0.038). However, the miR-34b rs4938723 polymorphism was not associated with the prevalence and prognosis of ACS. The G allele of miR-146a rs2910164 tends to be oxidized in ACS patients. The miRNA fractions purified from monocytes isolated from ACS patients were recognized by the 8OHG antibody. Mispairing of Oxi-miR-146a(G) with the 3'UTR of IKBA results in decreased IκBα protein expression and activation of the NF-κB inflammatory pathway. P65 expression was higher in atherosclerotic plaques from patients carrying the miR-146a rs2910164 G allele.

CONCLUSION

The variant of miR-146a rs2910164 is closely associated with the risk of ACS in Chinese Han population. Patients carrying miR-146a rs2910164 G allele may have worse pathological change and poorer post-PCI prognosis, partly due to the oxidatively modified miR-146a mispairing with 3'UTR of IKBA and activating NF-κB inflammatory pathways.

CD9 and folate receptor overexpression are not sufficient for VSV-G-independent lentiviral transduction

Extracellular vesicles have become a research focus for their potential as therapeutic vehicles that carry cargo substances. Extracellular vesicles may origin from the endosomal compartment and share several characteristics with the envelope of lentiviruses. A previous study reported that constitutive expression of the tetraspanin CD9, an extracellular vesicle marker, not only increases vesicle secretion from cells, but has also a positive effect on lentiviral transduction efficiency. Moreover, it was shown that expression of CD9 on the viral envelope in absence of viral glycoproteins was sufficient for the transduction of mammalian cells. In this study, we investigate the effect of CD9 and folate receptor alpha, a GPI-anchored protein, on biosynthesis and transduction efficiency of vesicles carrying lentiviral vectors. We demonstrate that neither CD9 nor FRα nor the combination of both were able to mediate a significant transduction of therapeutic vesicles carrying lentiviral RNA. Further studies are required to identify endogenous mammalian proteins that can be used for pseudotyping of viral envelopes to improve viral targeting without inducing immune responses.

Tetraspanin CD9 is Regulated by miR-518f-5p and Functions in Breast Cell Migration and In Vivo Tumor Growth

Breast cancer is the most commonly diagnosed and the second leading cause of cancer-related mortality among women worldwide. miR-518f-5p has been shown to modulate the expression of the metastasis suppressor CD9 in prostate cancer. However, the role of miR-518f-5p and CD9 in breast cancer is unknown. Therefore, this study aimed to elucidate the role of miR-518f-5p and the mechanisms responsible for decreased CD9 expression in breast cancer, as well as the role of CD9 in de novo tumor formation and metastasis. miR-518f-5p function was assessed using migration, adhesion, and proliferation assays. miR-518f-5p was overexpressed in breast cancer cell lines that displayed significantly lower CD9 expression as well as less endogenous CD9 3'UTR activity, as assessed using qPCR and dual luciferase assays. Transfection of miR-518f-5p significantly decreased CD9 protein expression and increased breast cell migration in vitro. Cd9 deletion in the MMTV/PyMT mouse model impaired tumor growth, but had no effect on tumor initiation or metastasis. Therefore, inhibition of miR-518f-5p may restore CD9 expression and aid in the treatment of breast cancer metastasis.

Downregulated circular RNA itchy E3 ubiquitin protein ligase correlates with advanced pathologic T stage, high lymph node metastasis risk and poor survivals in prostate cancer patients

OBJECTIVE

This study aimed to explore the correlation of circular RNA itchy E3 ubiquitin protein ligase (circ-ITCH) with pathological features as well as its predictive value on prognosis in prostate cancer patients.

METHODS

Three hundred and twenty-four patients with prostate cancer underwent radical prostatectomy were consecutively included in this retrospective study, and patients' specimens of tumor as well as paired adjacent tissues were collected for detection of circ-ITCH expression. Patients' baseline characteristics and survival data were obtained from follow-up records, and correlation of circ-ITCH with patients' pathological features and survival was determined.

RESULTS

Circ-ITCH expression was decreased in tumor tissue compared with paired adjacent tissues (P< 0.001), and it presented with good value in distinguishing tumor tissues from paired adjacent tissues with area under curve (AUC) of 0.812 (95%CI: 0.780-0.845). Circ-ITCH low expression was associated with advanced pathologic T stage (P= 0.002) and high risk of lymph node metastasis (P= 0.047) in prostate cancer patients. As for prognosis, patients with circ-ITCH high expression had longer disease-free survival (DFS) (P< 0.001) and overall survival (OS) (P< 0.001). Additionally, circ-ITCH (high vs. low) independently predicted better survival, while Gleason score (> 7 vs. ⩽ 7) and surgical margin status (positive vs. negative) independently predicted worse survival in prostate patients underwent radical prostatectomy.

CONCLUSIONS

Circ-ITCH is downregulated in prostate cancer tissues, and its low expression correlates with advanced pathologic T stage, high lymph mode metastasis risk and poor survival in prostate cancer patients underwent radical prostatectomy.

Extracellular vesicles with altered tetraspanin CD9 and CD151 levels confer increased prostate cell motility and invasion

To facilitate intercellular communication, cells release nano-sized, extracellular vesicles (EVs) to transfer biological cargo to both local and distant sites. EVs are enriched in tetraspanins, two of which (CD9 and CD151) have altered expression patterns in many solid tumours, including prostate cancer, as they advance toward metastasis. We aimed to determine whether EVs from prostate cells with altered CD9 and CD151 expression could influence cellular behaviour and increase the metastatic capabilities of non-tumourigenic prostate cells. EVs were isolated by ultrafiltration and characterised for their tetraspanin expression and size distribution. iTRAQ was used to identify differences between RWPE1 and tetraspanin-modified RWPE1 EV proteomes, showing an enrichment in protein degradation pathways. Addition of EVs from RWPE1 cells with reduced CD9 or increased CD151 abundance resulted in increased invasion of RWPE1 cells, and increased migration in the case of high CD151 abundance. We have been able to show that alteration of CD9 and CD151 on prostate cells alters the proteome of their resultant EVs, and that these EVs can enhance the migratory and invasive capabilities of a non-tumourigenic prostate cellular population. This work suggests that cellular tetraspanin levels can alter EVs, potentially acting as a driver of metastasis in prostate cancer.