Exosomal circ_0084043 derived from colorectal cancer-associated fibroblasts promotes in vitro endothelial cell angiogenesis by regulating the miR-140-3p/HIF-1α/VEGF signaling axis.

Background: Circular RNAs (circRNAs) hold potential as diagnostic markers for colorectal cancer (CRC); however, their functional mechanisms remain incompletely elucidated. This work investigates the clinical implications of a unique set comprising six circRNAs derived from serum in CRC. Furthermore, we delve into the role of exosomal circ_0084043, originating from colorectal cancer-associated fibroblasts (CAFs), with a specific focus on its contribution to endothelial cell angiogenesis. Methods: The study analyzed circRNA levels in serum samples obtained from both CRC and control groups using qRT-PCR. Additionally, exosomes originating from colorectal CAFs and normal fibroblasts (NFs) were purified and confirmed by electron microscopy and Western blotting techniques. The proangiogenic effects of CAF-derived exosomal circ_0084043 were assessed in endothelial cells through proliferation, migration, and in vitro capillary tube formation assays. Gain- and loss-of-function experiments were employed to clarify the role of the circ_0084043/miR-140-3p/HIF-1α axis in endothelial cell angiogenesis, utilizing luciferase reporter assay, Western blotting, and ELISA for mechanism elucidation. Results: The candidate circRNAs (circ_0060745, circ_001569, circ_007142, circ_0084043, Circ_BANP, and CiRS-7) exhibited notably elevated expression in CRC patient sera compared to the levels observed in healthy individuals. Except for CiRS-7, all circRNAs showed elevated expression in CRC patients with positive lymph node metastasis and advanced tumor stages. Exosomes released by colorectal CAFs augmented endothelial cell proliferation, migration, and angiogenesis by upregulating VEGF expression and secretion. Circ_0084043 was highly detected in endothelial cells treated with CAF-derived exosomes. Silencing circ_0084043 reduced VEGFA expression and diminished CAF exosome-induced endothelial cell processes, indicating its pivotal role in angiogenesis. Circ_0084043 sponges miR-140-3p, regulating HIF-1α, and a reverse relationship was also identified between miR-140-3p and VEGFA in endothelial cells. Inhibiting miR-140-3p mitigated circ_0084043 knockdown effects in CAF exosome-treated endothelial cells. Co-transfection of si-circ_0084043 and a miR-140-3p inhibitor reversed the inhibited migration and angiogenesis caused by circ_0084043 knockdown in CAF exosome-treated endothelial cells. Inhibiting miR-140-3p rescued reduced VEGFA expression due to circ_0084043 knockdown in endothelial cells exposed to CAF-derived exosomes, indicating modulation of the circ_0084043/miR-140-3p/VEGF signaling in CAF-derived exosome-induced angiogenesis. Conclusions: This study unveiled a distinctive signature of six serum-derived circular RNAs, indicating their potential as promising diagnostic biomarkers for CRC. Importantly, exosomal circ_0084043 originating from colorectal CAFs was identified as playing a crucial role in endothelial cell angiogenesis, exerting its influence through the modulation of the miR-140-3p/HIF-1α/VEGF signaling axis.

Exosomes derived from colorectal cancer cells take part in activation of stromal fibroblasts through regulating PHLPP isoforms.

Given that tumor cells primarily instigate systemic changes through exosome secretion, our study delved into the role of colorectal cancer (CRC)-secreted exosomal miR-224 in stromal reprogramming and its impact on endothelial cell angiogenesis. Furthermore, we assessed the potential clinical significance of a specific signature of circulating serum-derived miRNAs, serving as a non-invasive biomarker for CRC diagnosis. Circulating serum-derived miR-103a-3p, miR-135b-5p, miR-182-5p, and miR-224-5p were significantly up-regulated, while miR-215-5p, and miR-455-5p showed a significant down-regulation in CRC patients than in healthy individuals. Our findings indicated that the expressions of CAF-specific markers (α-SMA and FAP) and CAF-derived cytokines (IL-6, and SDF-1) were induced in fibroblasts stimulated with SW480 CRC exosomes, partly due to Akt activation. As a plausible mechanism, exosomal transfer of miR-224 from SW40 CRC cells may activate stromal fibroblasts, which in turn, may promote endothelial cell sprouting. The study identified PHLPP1 and PHLPP2 as direct targets of miR-224 and demonstrated that CRC-secreted exosomal miR-224 activates Akt signaling by regulating PHLPP1/2 in activated fibroblasts, thereby affecting the stromal cell proliferation and migration. This study established a panel of six-circulating serum-derived miRNAs as a non-invasive biomarker for CRC diagnosis. Also, we proposed a supporting model in which CRC-secreted exosomal miR-224 takes part in the stromal reprogramming to CAFs partly through regulating Akt signaling. This may affect the malignant biological behavior of activated stromal cells and thereby elicit a vascular response within the microenvironment of CRC cells. See also the graphical abstract(Fig. 1).

Cancer-associated fibroblasts drive colorectal cancer cell progression through exosomal miR-20a-5p-mediated targeting of PTEN and stimulating interleukin-6 production.

BACKGROUND: This study evaluated the clinical relevance of a set of five serum-derived circulating microRNAs (miRNAs) in colorectal cancer (CRC). Additionally, we investigated the role of miR-20a-5p released by exosomes derived from cancer-associated fibroblasts (CAFs) in the context of CRC. METHODS: The expression levels of five circulating serum-derived miRNAs (miR-20a-5p, miR-122-5p, miR-139-3p, miR-143-5p, and miR-193a-5p) were quantified by real-time quantitative PCR (RT-qPCR), and their associations with clinicopathological characteristics in CRC patients were assessed. The diagnostic accuracy of these miRNAs was determined through Receiver Operating Characteristic (ROC) curve analysis. CAFs and normal fibroblasts (NFs) were isolated from tissue samples, and subsequently, exosomes derived from these cells were isolated and meticulously characterized using electron microscopy and Western blotting. The cellular internalization of fluorescent-labeled exosomes was visualized by confocal microscopy. Gain- and loss-of-function experiments were conducted to elucidate the oncogenic role of miR-20a-5p transferred by exosomes derived from CAFs in CRC progression. The underlying mechanisms were uncovered through luciferase reporter assay, Western blotting, enzyme-linked immunosorbent assays, as well as proliferation and migration assays. RESULTS: The expression levels of serum-derived circulating miR-20a-5p and miR-122-5p were significantly higher in CRC and were positively correlated with advanced stages of tumorigenesis and lymph node metastasis (LNM). In contrast, circulating miR-139-3p, miR-143-5p, and miR-193a-5p were down-regulated in CRC and associated with early tumorigenesis. Except for miR-139-3p, they showed a negative correlation with LNM status. Among the candidate miRNAs, significantly elevated levels of miR-20a-5p were observed in both cellular and exosomal fractions of CAFs. Our findings indicated that miR-20a-5p induces the expression of EMT markers, partly by targeting PTEN. Exosomal miR-20a secreted by CAFs emerged as a key factor enhancing the proliferation and migration of CRC cells. The inhibition of miR-20a impaired the proliferative and migratory potential of CAF-derived exosomes in SW480 CRC cells, suggesting that the oncogenic effects of CAF-derived exosomes are mediated through the exosomal transfer of miR-20a. Furthermore, exosomes originating from CAFs induced increased nuclear translocation of the NF-kB p65 transcription factor in SW480 CRC cells, leading to increased interleukin-6 (IL-6) production. CONCLUSIONS: We established a set of five circulating miRNAs as a non-invasive biomarker for CRC diagnosis. Additionally, our findings shed light on the intricate mechanisms underpinning the oncogenic impacts of CAF-derived exosomes and underscore the pivotal role of miR-20a-5p in CRC progression.

Hsa-miR-194-5p and hsa-miR-195-5p are down-regulated expressed in high dysplasia HPV-positive Pap smear samples compared to normal cytology HPV-positive Pap smear samples.

BACKGROUND: The human papillomavirus (HPV) infection may affect the miRNA expression pattern during cervical cancer (CC) development. To demonstrate the association between high-risk HPVs and the development of cervix dysplasia, we examined the expression patterns of hsa-miR-194-5p and hsa-miR-195-5p in Pap smear samples from southeast Iranian women. We compared samples that were HPV-positive but showed no abnormality in the cytological examination to samples that were HPV-positive and had severe dysplasia. METHODS: Pap smear samples were obtained from 60 HPV-positive (HPV-16/18) patients with histologically confirmed severe dysplasia (cervical intra-epithelial neoplasia (CIN 3) or carcinoma in situ) and the normal cytology group. The expression of hsa-miR-194-5p and hsa-miR-195-5p was analyzed by real-time quantitative PCR, using specific stem-loop primers and U6 snRNA as the internal reference gene. Clinicopathological features were associated with miRNA expression levels. Furthermore, functional enrichment analysis was conducted using in silico tools. The Kaplan-Meier survival method was also obtained to discriminate survival-significant candidate miRNAs in CC, and receiver operating characteristic (ROC) curves were constructed to assess the diagnostic value. RESULTS: Compared to HPV-positive cytologically normal Pap smear samples, hsa-miR-194-5p and hsa-miR-195-5p relative expression decreased significantly in HPV-positive patients with a severe dysplasia Pap smear. Kaplan-Meier analysis indicated a significant association between the miR-194 decrease and poor CC survival. In essence, ROC curve analysis showed that miR-194-5p and miR-195-5p could serve as valuable markers for the development of cervix dysplasia in individuals who are positive for high-risk HPVs. CONCLUSIONS: This study revealed that hsa-miR-194-5p and hsa-miR-195-5p may possess tumor suppressor capabilities in the context of cervical dysplasia progression. However, it remains uncertain whether these microRNAs are implicated in the transition of patients with high dysplasia to cervical cancer. We also showed the potential capability of candidate miRNAs as novel diagnostic biomarkers related to cervical dysplasia progression.

Colorectal cancer-secreted exosomal circ_001422 plays a role in regulating KDR expression and activating mTOR signaling in endothelial cells by targeting miR-195-5p.

BACKGROUND: As non-coding RNAs, exosomal circular RNAs (circRNAs) regulate colorectal cancer (CRC) progression, although the functional mechanisms by which such molecules affect the tumor microenvironment are still elusive. Herein, we aimed to explore the potential clinical significance of a signature of five serum-derived circRNAs in CRC and investigated the mechanisms underlying endothelial cell angiogenesis mediated by CRC-secreted exosomal circ_001422. METHODS: The expression of a signature of five serum-derived circRNAs (circ_0004771, circ_0101802, circ_0082333, circ_0072309, and circ_001422) were measured by RT-qPCR, and their associations with tumor staging and lymph node metastasis were further evaluated in CRC patients. In silico analysis was used to show the relationship between circ_001422, miR-195-5p, and KDR, validated by dual-luciferase reporter and Western blotting assays. CRC cell-derived exosomes were isolated and characterized by scanning electron microscopy and Western blotting. Endothelial cell uptake of PKH26-labeled exosomes was demonstrated using a spectral confocal microscope. In vitro genetic strategies were used to exogenously alter the expression level of circ_001422 and miR-195-5p expression. Cell proliferation assay, transwell migration assay, and capillary tube formation assay were conducted to explore the role of CRC-secreted exosomal circ_001422 in endothelial cell function in vitro. RESULTS: The expression levels of serum-derived circ_0004771, circ_0101802, circ_0082333, and circ_001422 were significantly higher in CRC and were positively correlated with the lymph node metastasis status. However, circ_0072309 showed a significant down-regulation in CRC than in healthy individuals. Furthermore, a higher expression level of circ_001422 in both cellular and exosomal fractions was found in HCT-116 CRC cells. We found that HCT-116 exosomes considerably enhanced proliferation and migration of endothelial cells through shuttling of circ_001422. We also observed that exosomes derived from HCT-116 cell, but not non-aggressive Caco-2 CRC cells, increased in vitro tubulogenesis of endothelial cells. Importantly, knockdown of circ_001422 impaired the capability of endothelial cells to form the capillary-like tube structures. CRC-secreted circ_001422 acted as an endogenous miR-195-5p sponge to inhibit miR-195-5p activity, which led to increased KDR expression and mTOR signaling activation in endothelial cells. Importantly, ectopic expression of miR-195-5p mimicked the effect of circ_001422 silencing on KDR/mTOR signaling in endothelial cells. CONCLUSION: This study attributed a biomarker role for circ_001422 in CRC diagnosis and proposed a novel mechanism whereby circ_001422 up-regulates KDR through sponging miR-195-5p. These interactions may give rise to the activation of mTOR signaling and may be a possible clarification for the pro-angiogenesis effects of CRC-secreted exosomal circ_001422 on endothelial cells.

Circulating serum miR-1246 and miR-1229 as diagnostic biomarkers in colorectal carcinoma.

Background: Colorectal cancer (CRC) is one of the most common cancers worldwide. Although colonoscopy is considered as the "Gold Standard" technique to detect CRC, its application is invasive and cost incurred. Thus, noninvasive or minimally invasive approaches are of utmost importance. The aberrant expression of some microRNAs (miRNAs, miRs) has been suggested in association with CRC pathogenesis. This study aimed to validate if circulating serum miR-1229 and miR-1246 are diagnostic biomarkers for CRC. Materials and Methods: Serum samples were isolated from 45 CRC patients and also 45 healthy controls (HC). The expression levels of circulating serum-derived miR-1229 and miR-1246 were evaluated by quantitative real-time polymerase chain reaction. Receiver operating characteristic (ROC) curves were constructed to evaluate the CRC diagnostic accuracy of selected miRNAs. Furthermore, the association of candidate miRNAs and clinicopathological characteristics were evaluated. Functional enrichment of the candidate miRNAs was applied using in silico tools. Results: The expression of miR-1229 and miR-1246 was significantly higher in CRC patients than HC (P < 0.0001) and also was found in association with lymph node metastasis (P < 0.05). We demonstrated a significant up-regulation of serum-derived miR-1246 in advanced tumor-node-metastasis stage III of CRC patients (P < 0.05). Areas under the ROC curve of miR-1229 and miR-1246 were 0.81 and 0.84, respectively (P < 0.0001). Conclusion: We confirmed the capability of circulating serum miR-1229 and miR-1246 as novel diagnostic biomarkers for CRC.

Circular RNAs play roles in regulatory networks of cell signaling pathways in human cancers.

AIMS: Circular RNAs (circRNAs) are endogenous covalently closed non-coding RNAs produced by reverse splicing of linear RNA. These molecules are highly expressed in mammalian cells and show cell/tissue-specific expression patterns. They are also significantly dysregulated in various cancers and function as oncogenes or tumor suppressors. Emerging evidence reveals that circRNAs contribute to cancer progression via modulating different cell signaling pathways. Nevertheless, the functional significance of circRNAs in cell signaling pathways regulation is still largely elusive. Considering this, shedding light on the multi-pathway effects of circRNAs may improve our understanding of targeted cancer therapy. Here, we discuss how circRNAs regulate the major cell signaling pathways in human cancers. MATERIALS AND METHODS: We adopted a systematic search in PubMed using the following MeSH terms: circRNAs, non-coding RNAs, lncRNAs, exosomal circRNAs, cancer, and cell signaling. KEY FINDINGS: We discussed different roles of circRNAs during tumorigenesis in which circRNAs affect tumor development through activating or inactivating certain cell signaling pathways via molecular interactions using various signaling pathways. We also discussed how crosstalk between circRNAs and lncRNAs modulate tumorigenesis and provides a resource for the identification of cancer therapeutic targets. SIGNIFICANCE: We here elucidated how circRNAs can modulate different cell signaling pathways and play roles in cancer. This can broaden our horizons toward introducing promising prognostic, diagnostic, and therapeutic targets.

Strategies to overcome the side effects of chimeric antigen receptor T cell therapy.

Chimeric antigen receptor (CAR) therapy is a method directing T lymphocytes against antigens on the surface of tumors, increasing target cell elimination. Genetic engineering enhances the capability of immune cells to detect new antigens expressed on cell surfaces. CAR T cell therapy is a significant breakthrough for treating human malignancies; however, different side effects (e.g., cytokine release syndrome) restrict its application. Improving design and using various combined receptors enhance the performance of these cells. This review discusses limitations and risk factors associated with CAR T cell therapy. We also review some alternative approaches for developing the next generation of CAR T cells.

Association between TBXT rs2305089 polymorphism and chordoma in Iranian patients identified by a developed T-ARMS-PCR assay.

BACKGROUND: Chordoma is a locally aggressive bone tumor with a high capability of recurrence. Because chordoma often occurs at critical locations next to neurovascular structures, there is an urgent need to introduce validated biomarkers. T-box transcription factor T (TBXT; OMIM: 601397) plays an important role in the pathogenesis and survival of chordoma cells. METHODS: Herein, we aimed to show whether rs2305089 polymorphism is correlated with chordoma in the Iranian population. In order to detect rs2305089, tetra-primer amplification refractory mutation system-polymerase chain reaction (T-ARMS-PCR) was used. In total, 19 chordoma patients and 108 normal healthy individuals were recruited and screened using T-ARMS-PCR. The results were subsequently validated by Sanger sequencing. RESULTS: The genotype distributions and allele frequencies were significantly different among the patient and healthy groups (p-value <0.05). The A allele of rs2305089 showed a significant positive association with chordoma risk (p-value <0.05). DNA sequencing verified the T-ARMS-PCR results as well. This study demonstrated the association between TBXT rs2305089 and chordoma in an Iranian population using a simple, accurate, and cost-effective T-ARMS-PCR assay. CONCLUSIONS: Our results were in line with those of previous studies showing that TBXT rs2305089 is associated with chordoma development. We also developed an efficient T-ARMS-PCR assay to determine the genotype of rs2305089.

SMAD4 contributes to chondrocyte and osteocyte development.

Different cellular and molecular mechanisms contribute to chondrocyte and osteocyte development. Although vital roles of the mothers against decapentaplegic homolog 4 (also called 'SMAD4') have been discussed in different cancers and stem cell-related studies, there are a few reviews summarizing the roles of this protein in the skeletal development and bone homeostasis. In order to fill this gap, we discuss the critical roles of SMAD4 in the skeletal development. To this end, we review the different signalling pathways and also how SMAD4 defines stem cell features. We also elaborate how the epigenetic factors-ie DNA methylation, histone modifications and noncoding RNAs-make a contribution to the chondrocyte and osteocyte development. To better grasp the important roles of SMAD4 in the cartilage and bone development, we also review the genotype-phenotype correlation in animal models. This review helps us to understand the importance of the SMAD4 in the chondrocyte and bone development and the potential applications for therapeutic goals.

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.

Identification of a six-microRNA signature as a potential diagnostic biomarker in breast cancer tissues.

BACKGROUND: Breast cancer (BC) is by far the most common malignancy among women. Epigenetic modulators, microRNAs in particular, may set stages for BC development and its progression. Herein, we aimed to assess the diagnostic potentiality of a signature of six miRNAs (i.e., hsa-miR-25-3p, -29a-5p, -105-3p, -181b1-5p, -335-5p, and -339-5p) in BC and adjacent non-tumor tissues. METHODS: A pair of 50 tumor and adjacent non-tumor samples were taken from BC patients. The expression of each candidate miRNA was measured using quantitative reverse transcription PCR. To investigate the possible roles of each miRNA and their impressions on BC prognosis, in silico tools were used. Receiver operating characteristic (ROC) curves were performed to determine the diagnostic accuracy of each miRNA and the possible association of their expression with clinicopathological characteristics was analyzed. RESULTS: Our findings showed the upregulation of hsa-miR-25-3p, -29a-5p, -105-3p, and -181b1-5p, and the downregulation of hsa-miR-335-5p and -339-5p in BC tumor compared to corresponding adjacent tissues. Except for hsa-miR-339-5p, the up-/down-regulation of the candidate miRNAs was associated with TNM stages. Except for hsa-miR-105-3p, each candidate miRNA was correlated with HER-2 status. ROC curve analysis showed that the signature of six-miRNA is a potential biomarker distinguishing between tumor and non-tumor breast tissue samples. CONCLUSION: We showed that the dysregulation of a novel signature of six-miRNA can be used as a potential biomarker for BC diagnosis.

Functions of the SNAI family in chondrocyte-to-osteocyte development.

Different cellular mechanisms contribute to osteocyte development. And while critical roles for members of the zinc finger protein SNAI family (SNAIs) have been discussed in cancer-related models, there are few reviews summarizing their importance for chondrocyte-to-osteocyte development. To help fill this gap, we review the roles of SNAIs in the development of mature osteocytes from chondrocytes, including the regulation of chondro- and osteogenesis through different signaling pathways and in programmed cell death. We also discuss how epigenetic factors-including DNA methylation, histone methylation and acetylation, and noncoding RNAs-contribute differently to both chondrocyte and osteocyte development. To better grasp the important roles of SNAIs in bone development, we also review genotype-phenotype correlations in different animal models. We end with comments about the possible importance of the SNAI family in cartilage/bone development and the potential applications for therapeutic goals.

Prevalence and Genotype Distribution of Human Papillomavirus Infection among 12 076 Iranian Women.

INTRODUCTION: Human papillomavirus (HPV) infection is one of the major health concerns of women in developing countries. This study gives an insight into the prevalence and genotype distribution of HPV infection and compares it with Pap smear results among Iranian women. METHODS: In this study, 12 076 Iranian women underwent routine examination from November 2016 to November 2018 using HPV Direct Flow CHIP System for HPV DNA typing. Cytology was undertaken for 5138 samples. RESULTS: Overall HPV prevalence was calculated at 38.68%. The most frequent HPV types were HPV 6, 16, 11, 62/81, 52 and 54. The most high-risk HPV (HR-HPV) types were HPV 16, 52, 18, 39, 31 and 51. These 2 groups represent approximately half of all HPV types detected, 47% and 55%, respectively. Among individuals who underwent cytological tests, 135 individuals (2.63%) were cytologically positive. In this group, 81 individuals (60%) were HPV positive, 62 (76%) of whom were HR-HPV positive, most frequently with HPV 16 (34%). CONCLUSION: This study highlights the urgent need for public education and early diagnosis using HPV screening tests to prevent cervical cancer.

The oncogenic and tumor suppressive roles of RNA-binding proteins in human cancers.

Posttranscriptional regulation is a mechanism for the cells to control gene regulation at the RNA level. In this process, RNA-binding proteins (RBPs) play central roles and orchestrate the function of RNA molecules in multiple steps. Accumulating evidence has shown that the aberrant regulation of RBPs makes  contributions to the initiation and progression of tumorigenesis via numerous mechanisms such as genetic changes, epigenetic alterations, and noncoding RNA-mediated regulations. In this article, we review the effects caused by RBPs and their functional diversity in the malignant transformation of cancer cells that occurs through the involvement of these proteins in various stages of RNA regulation including alternative splicing, stability, polyadenylation, localization, and translation. Besides this, we review the various interactions between RBPs and other crucial posttranscriptional regulators such as microRNAs and long noncoding RNAs in the pathogenesis of cancer. Finally, we discuss the potential approaches for targeting RBPs in human cancers.

Docosahexaenoic acid reverses the promoting effects of breast tumor cell-derived exosomes on endothelial cell migration and angiogenesis.

AIM: As a natural compound, docosahexaenoic acid (DHA) exerts anti-cancer and anti-angiogenesis functions through exosomes; however, little is known about the molecular mechanisms. MAIN METHODS: Breast cancer (BC) cells were treated with DHA (50 µM) and then tumor cell-derived exosomes (TDEs) were collected and characterized by electron microscopy, dynamic light scattering, and western blot analyses. By the time the cells were treated with DHA, RT-qPCR was used to investigate the expression of vascular endothelial growth factor (VEGF) and the selected pro- and anti-angiogenic microRNAs (miRNAs). The quantification of secreted VEGF protein was measured by enzyme-linked immunosorbent assay (ELISA). The effects of TDEs on endothelial cell angiogenesis were explored by transwell cell migration and in vitro vascular tube formation assays. KEY FINDINGS: DHA treatment caused a significant and time-dependent decrease in the expression and secretion of VEGF in/from BC cells. This also increased expression of anti-angiogenic miRNAs (i.e. miR-34a, miR-125b, miR-221, and miR-222) while decreased levels of pro-angiogenic miRNAs (i.e. miR-9, miR-17-5p, miR-19a, miR-126, miR-130a, miR-132, miR-296, and miR-378) in exosomes derived from DHA-treated BC cells, TDE (DHA+). While treatment with exosomes (100 µg/ml) obtained from untreated BC cells, TDE (DHA-), enhanced the expression of VEGF-A in human umbilical vein endothelial cells (HUVECs), incubation with DHA or TDE (DHA+) led to the significant decrease of VEGF-A transcript level in these cells. We indicated that the incubation with TDE (DHA+) could significantly decrease endothelial cell proliferation and migration and also the length and number of tubes made by HUVECs in comparison with endothelial cells incubated with exosomes obtained from untreated BC cells. SIGNIFICANCE: DHA alters angiogenesis by shifting the up-regulation of exosomal miRNA contents from pro-angiogenic to anti-angiogenic, resulting in the inhibition of endothelial cell angiogenesis. These data can help to figure out DHA's anti-cancer function, maybe its use in cancer therapy.

Upregulation of the long noncoding RNAs DSCAM-AS1 and MANCR is a potential diagnostic marker for breast carcinoma.

Breast cancer (BC) is one of the most common malignancies among women in the world. There is a global attempt to diagnose BC as early as possible. Long noncoding RNAs (lncRNAs) are emerging as novel targets and biomarkers for BC diagnosis and prognosis. Aberrant expression of lncRNAs is associated with BC development, making them a potential tumor marker for BC. To investigate this possibility, we determined the expression levels of Down syndrome cell adhesion molecule-antisense RNA-1 (DSCAM-AS1) and mitotically-associated long non-coding RNA (MANCR) lncRNAs in BC tissues. This case-control study included 50 paired tumor and adjacent nontumor tissues from female BC patients. The total RNA was isolated and the expression levels of MANCR and DSCAM-AS1 lncRNAs were assessed using quantitative real-time reverse transcription-PCR. Potential correlations between lncRNA levels and clinicopathological characteristics were also analyzed. DSCAM-AS1 and MANCR lncRNAs were significantly upregulated in BC tumor tissues compared with the adjacent nontumor tissues. We also found the significant upregulation of DSCAM-AS1 in advanced tumor-node-metastasis stage (TNM III) of BC tumor tissues. Furthermore, the expression of DSCAM-AS1 and MANCR in HER-2 positive patients was significantly higher than HER-2 negative affected individuals. Receiver operating characteristic curve analysis showed a satisfactory diagnostic efficacy (P value < 0.0001), which means that DSCAM-AS1 and MANCR lncRNAs can potentially serve as a biomarker. The present study might provide further approval for the clinical diagnostic significance of DSCAM-AS1 and MANCR lncRNAs that their high expressions were associated with aggressive clinical parameters of BC.

Advances of exosome isolation techniques in lung cancer.

Lung cancer (LC) is among the leading causes of death all over the world and it is often diagnosed at advanced or metastatic stages. Exosomes, derived from circulating vesicles that are released from the multivesicular body, can be utilized for diagnosis and also the prognosis of LC at early stages. Exosomal proteins, RNAs, and DNAs can help to better discern the prognostic and diagnostic features of LC. To our knowledge, there are various reviews on LC and the contribution of exosomes, but none of them are about the exome techniques and also their efficiency in LC. To fill this gap, in this review, we summarize the recent investigations regarding isolation and also the characterization of exosomes of LC cells. Furthermore, we discuss the noncoding RNAs as biomarkers and their applications in the diagnosis and prognosis of LC. Finally, we compare the efficacy of exosome isolation methods to better fi + 6 + guring out feasible techniques.

A panel of six-circulating miRNA signature in serum and its potential diagnostic value in colorectal cancer.

AIM: Colorectal carcinoma (CRC) is one of the most prevalent cancers throughout the world. Circulating serum-derived microRNAs (miRNAs, miRs) can be used as non-invasive biomarkers for CRC diagnosis. This study aimed to identify a panel of six serum exosomal miRNAs as novel diagnostic biomarkers for CRC. MAIN METHODS: Exosomes were isolated and characterized from the conditioned media of the human colon adenocarcinoma cells (HCT-116 and Caco2). Sera were isolated from peripheral blood of 45 CRC and also 45 healthy individuals. The expression levels and diagnostic value of candidate circulating miRNAs (miR-19a, miR-20a, miR-150, miR-143, miR-145, and let-7a) were measured through quantitative real-time PCR. Receiver operating characteristic (ROC) curves were applied to evaluate the diagnostic accuracy of selected miRNAs. The association of candidate miRNAs and clinicopathological characteristics e.g. tumor node metastasis (TNM) staging and lymph node metastasis (LNM) were further evaluated. KEY FINDINGS: Circulating serum miR-19a, miR-20a, miR-150, and let-7a were significantly up-regulated in CRC patients, while miR-143 and miR-145 showed a significant down-regulation. The higher levels of miR-143 and miR-145 in patients with TNM stage I-II were detected, whereas miR-19a, miR-20a, miR-150, and let-7a were highly expressed in TNM stage III. The expression levels of miR-19a, miR-20a, and miR-150 were positively correlated with LNM status, while the expression levels of miR-143 and miR-145 were lower in patients with LNM. Area under the ROC curves of miR-19a, miR-20a, miR-150, miR-143, miR-145, and let-7a were 0.87, 0.83, 0.75, 0.76, 0.78 and 0.71, respectively. SIGNIFICANCE: We established a panel of six-circulating miRNA signature (i.e. miR-19a, miR-20a, miR-143, miR-145, miR-150, and let-7a) in serum as a non-invasive biomarker for CRC diagnosis. These findings confirm that serum-derived miRNAs have a strong potential to be a diagnostic biomarker for patients with CRC.

Non-coding RNAs underlying chemoresistance in gastric cancer.

BACKGROUND: Gastric cancer (GC) is a major health issue in the Western world. Current clinical imperatives for this disease include the identification of more effective biomarkers to detect GC at early stages and enhance the prevention and treatment of metastatic and chemoresistant GC. The advent of non-coding RNAs (ncRNAs), particularly microRNAs (miRNAs) and long-non coding RNAs (lncRNAs), has led to a better understanding of the mechanisms by which GC cells acquire features of therapy resistance. ncRNAs play critical roles in normal physiology, but their dysregulation has been detected in a variety of cancers, including GC. A subset of ncRNAs is GC-specific, implying their potential application as biomarkers and/or therapeutic targets. Hence, evaluating the specific functions of ncRNAs will help to expand novel treatment options for GC. CONCLUSIONS: In this review, we summarize some of the well-known ncRNAs that play a role in the development and progression of GC. We also review the application of such ncRNAs in clinical diagnostics and trials as potential biomarkers. Obviously, a deeper understanding of the biology and function of ncRNAs underlying chemoresistance can broaden horizons toward the development of personalized therapy against GC.