Epithelial-Mesenchymal Transition in Non-Small Cell Lung Cancer Management: Opportunities and Challenges

Lung cancer, the leading cause of death worldwide, is associated with the highest morbidity. Non-small cell lung cancer (NSCLC) accounts for 80-85% of lung cancer cases. Advances in the domain of cancer treatment have improved the prognosis and quality of life of patients with metastatic NSCLC. Nevertheless, tumor progression or metastasis owing to treatment failure caused by primary or secondary drug resistance remains the cause of death in the majority of cases. Epithelial-mesenchymal transition (EMT), a vital biological process wherein epithelial cancer cells lose their inherent adhesion and transform into more invasive mesenchymal-like cells, acts as a powerful engine driving tumor metastasis. EMT can also induce immunosuppression in the tumor environment, thereby promoting cancer development and poor prognosis among patients with NSCLC. This review aims to elucidate the effect of EMT on metastasis and the tumor immune microenvironment. Furthermore, it explores the possible roles of EMT inhibition in improving the treatment efficacy of NSCLC. Targeting EMT may be an ideal mechanism to inhibit tumor growth and progression at multiple steps.

Exosomal miR-1228-5p down-regulates DUSP22 to promotes cell proliferation and migration in small cell lung cancer

BACKGROUND

Exosomes play a crucial role in promoting tumor progression, dissemination, and resistance to treatment. These extracellular vesicles hold promise as valuable indicators for cancer detection. Our investigation focuses on exploring the significance and clinical relevance of exosomal miRNAs in small cell lung cancer (SCLC).

METHODS

Serum exosomes were isolated from both SCLC patients and healthy controls, and subjected to exosomal miRNA sequencing analysis. Mimics and inhibitors were employed to investigate the function of exosomal miR-1128-5p in cell migration and proliferation, both in vitro and in vivo. Western blot and luciferase assay were utilized to identify the interaction between miR-1228-5p and dual specificity phosphatase 22 (DUSP22).

RESULTS

Exosomal miRNA sequencing analysis revealed enrichment of specific miRNAs in SCLC compared to healthy controls. Circulating miR-1228-5p was upregulated in SCLC patients, associated with advanced stages, suggesting its potential oncogenic role. In vitro, miR-1228-5p expression was significantly higher in SCLC cells than in normal cells. SCLC cell-derived exosomes contained elevated levels of miR-1228-5p, facilitating its entry into co-cultured cells. Notably, migration and proliferation induced by SCLC exosomes were mainly mediated by miR-1228-5p. In vivo experiments confirmed these findings. Western blot analysis demonstrated miR-1228-5p's regulation of DUSP22 expression, and luciferase reporter assay validated DUSP22 as a direct target gene. Overexpressing DUSP22 counteracted miR-1228-5p's promotion of SCLC cell proliferation and migration.

CONCLUSIONS

Collectively, our results suggest that exosomes play a role in facilitating cancer growth and metastasis by delivering miR-1228-5p. Moreover, circulating exosomal miR-1228-5p may serve as a potential marker for SCLC diagnosis and prognosis.

Insights into the Molecular Mechanisms Mediating Extravasation in Brain Metastasis of Breast Cancer, Melanoma, and Lung Cancer

Brain metastasis is an incurable end-stage of systemic cancer associated with poor prognosis, and its incidence is increasing. Brain metastasis occurs through a multi-step cascade where cancer cells spread from the primary tumor site to the brain. The extravasation of tumor cells through the blood-brain barrier (BBB) is a critical step in brain metastasis. During extravasation, circulating cancer cells roll along the brain endothelium (BE), adhere to it, then induce alterations in the endothelial barrier to transmigrate through the BBB and enter the brain. Rolling and adhesion are generally mediated by selectins and adhesion molecules induced by inflammatory mediators, while alterations in the endothelial barrier are mediated by proteolytic enzymes, including matrix metalloproteinase, and the transmigration step mediated by factors, including chemokines. However, the molecular mechanisms mediating extravasation are not yet fully understood. A better understanding of these mechanisms is essential as it may serve as the basis for the development of therapeutic strategies for the prevention or treatment of brain metastases. In this review, we summarize the molecular events that occur during the extravasation of cancer cells through the blood-brain barrier in three types of cancer most likely to develop brain metastasis: breast cancer, melanoma, and lung cancer. Common molecular mechanisms driving extravasation in these different tumors are discussed.

miR-4731-5p Enhances Apoptosis and Alleviates Epithelial-Mesenchymal Transition through Targeting RPLP0 in Non-Small-Cell Lung Cancer

Background/Aim. MircoRNA-4731-5p (miR-4731-5p) is a new miRNA involved in different human cancers, but its function has not been clarified in non-small-cell lung cancer (NSCLC). The present study attended to resolve the role of miR-4731-5p in NSCLC. Materials and Methods. The expression level of miR-4731-5p or ribosomal protein large P0 (RPLP0) and NSCLC clinicopathologic characteristics were analyzed. The binding between miR-4731-5p and RPLP0 was confirmed by TargetScan prediction and luciferase reporter experiment. Also, the probable role of miR-4731-5p in NSCLC via RPLP0 was elaborated by the MTT, western blotting, immunofluorescence, transwell, flow cytometry, and TUNEL assays. Moreover, in vivo verification was conducted in xenografted nude mice. Results. The level of miR-4731-5p was notably declined in vivo and in vitro, which was involved in the prognosis of lung cancer patients. The miR-4731-5p mimic could remarkably restrain cell viability, invasion, and the translational expression level of vimentin and e-cadherin, with promoted cell apoptosis in NSCLC, which were notably reversed by RPLP0 overexpression. Conclusion. miR-4731-5p/RPLP0 axis might be an underlying therapeutic target for NSCLC.

Emerging role of exosomes as biomarkers in cancer treatment and diagnosis

Cancer is a leading cause of death worldwide and cancer incidence and mortality are rapidly growing. These massive amounts of cancer patients require rapid diagnosis and efficient treatment strategies. However, the currently utilized methods are invasive and cost-effective. Recently, the effective roles of exosomes as promising diagnostic, prognostic, and predictive biomarkers have been revealed. Exosomes are membrane-bound extracellular vesicles containing RNAs, DNAs, and proteins, and are present in a wide array of body fluids. Exosomal cargos have shown the potential to detect various types of cancers at early stages with high sensitivity and specificity. They can also delivery therapeutic agents efficiently. In this article, an overview of recent advances in the research of exosomal biomarkers and their applications in cancer diagnosis and treatment has been provided. Furthermore, the advantages and challenges of exosomes as liquid biopsy targets are discussed and the clinical implications of using exosomal miRNAs have been revealed.

Head to head evaluation of second generation ALK inhibitors brigatinib and alectinib as first-line treatment for ALK+ NSCLC using an in silico systems biology-based approach

Around 3-7% of patients with non-small cell lung cancer (NSCLC), which represent 85% of diagnosed lung cancers, have a rearrangement in the ALK gene that produces an abnormal activity of the ALK protein cell signaling pathway. The developed ALK tyrosine kinase inhibitors (TKIs), such as crizotinib, ceritinib, alectinib, brigatinib and lorlatinb present good performance treating ALK+ NSCLC, although all patients invariably develop resistance due to ALK secondary mutations or bypass mechanisms. In the present study, we compare the potential differences between brigatinib and alectinib's mechanisms of action as first-line treatment for ALK+ NSCLC in a systems biology-based in silico setting. Therapeutic performance mapping system (TPMS) technology was used to characterize the mechanisms of action of brigatinib and alectinib and the impact of potential resistances and drug interferences with concomitant treatments. The analyses indicate that brigatinib and alectinib affect cell growth, apoptosis and immune evasion through ALK inhibition. However, brigatinib seems to achieve a more diverse downstream effect due to a broader cancer-related kinase target spectrum. Brigatinib also shows a robust effect over invasiveness and central nervous system metastasis-related mechanisms, whereas alectinib seems to have a greater impact on the immune evasion mechanism. Based on this in silico head to head study, we conclude that brigatinib shows a predicted efficacy similar to alectinib and could be a good candidate in a first-line setting against ALK+ NSCLC. Future investigation involving clinical studies will be needed to confirm these findings. These in silico systems biology-based models could be applied for exploring other unanswered questions.

Correlation of exosomal microRNA clusters with bone metastasis in non-small cell lung cancer

20–40% of lung cancer patients develop bone metastasis (BM) with significantly decreased overall survival. Currently, BM is mainly diagnosed by computerized tomography (CT) scan or magnetic resonance imaging (MRI) when symptom develops. Novel biomarkers with higher prediction value of BM are needed. Plasma-derived exosomal microRNAs had been isolated and sequenced of total 30 non-small cell lung cancer (NSCLC) patients including 16 with bone metastasis and 14 without bone metastasis. Hierarchical clustering based on the total miRNA profile can clearly separate cancer patients and healthy individuals (H), but not patients with (BM +) or without (BM−) BM. Weight Co-expression network of miRNAs (WGCNA) analyses identified three consensus clusters (A, B, C) of highly correlated miRNAs, among which cluster B (144 miRNAs) showed significantly differential expression in lung cancer patients, especially in BM + group. Pathway analysis of cluster B miRNAs revealed enrichment in metabolic pathways that may involve in preconditioning of the metastatic niche. Three differentially expressed miRNAs between BM + and BM− patients within cluster B were identified as miR-574-5p, a suppressor of Wnt/β-catenin pathway, was down-regulated, while miR-328-3p and miR-423-3p, two activators of the same pathway, were up-regulated in BM + patients. Cluster A miRNAs (n = 49) also showed trend of upregulation in BM + patients. Interestingly, pathway analysis indicated that 43 of them are associated with chromosome14, which has been suggested to promote epithelial-mesenchymal transition (EMT) and bone metastasis.

Therapeutically Significant MicroRNAs in Primary and Metastatic Brain Malignancies

Simple Summary

The overall survival of brain cancer patients remains grim, with conventional therapies such as chemotherapy and radiotherapy only providing marginal benefits to patient survival. Cancers are complex, with multiple pathways being dysregulated simultaneously. Non-coding RNAs such as microRNA (miRNAs) are gaining importance due to their potential in regulating a variety of targets implicated in the pathology of cancers. This could be leveraged for the development of targeted and personalized therapies for cancers. Since miRNAs can upregulate and/or downregulate proteins, this review aims to understand the role of these miRNAs in primary and metastatic brain cancers. Here, we discuss the regulatory mechanisms of ten miRNAs that are highly dysregulated in glioblastoma and metastatic brain tumors. This will enable researchers to develop miRNA-based targeted cancer therapies and identify potential prognostic biomarkers.

Abstract

Brain cancer is one among the rare cancers with high mortality rate that affects both children and adults. The most aggressive form of primary brain tumor is glioblastoma. Secondary brain tumors most commonly metastasize from primary cancers of lung, breast, or melanoma. The five-year survival of primary and secondary brain tumors is 34% and 2.4%, respectively. Owing to poor prognosis, tumor heterogeneity, increased tumor relapse, and resistance to therapies, brain cancers have high mortality and poor survival rates compared to other cancers. Early diagnosis, effective targeted treatments, and improved prognosis have the potential to increase the survival rate of patients with primary and secondary brain malignancies. MicroRNAs (miRNAs) are short noncoding RNAs of approximately 18–22 nucleotides that play a significant role in the regulation of multiple genes. With growing interest in the development of miRNA-based therapeutics, it is crucial to understand the differential role of these miRNAs in the given cancer scenario. This review focuses on the differential expression of ten miRNAs (miR-145, miR-31, miR-451, miR-19a, miR-143, miR-125b, miR-328, miR-210, miR-146a, and miR-126) in glioblastoma and brain metastasis. These miRNAs are highly dysregulated in both primary and metastatic brain tumors, which necessitates a better understanding of their role in these cancers. In the context of the tumor microenvironment and the expression of different genes, these miRNAs possess both oncogenic and/or tumor-suppressive roles within the same cancer.

PSMB8-AS1 activated by ELK1 promotes cell proliferation in glioma via regulating miR-574-5p/RAB10

Long noncoding RNAs (lncRNAs) get great involvements in the development of countless cancers. Nonetheless, the deep molecular mechanism by which lncRNA regulates the formation of glioma is unclear. In our study, the expression of PSMB8-AS1 was dramatically upregulated in glioma tissues and cells, further, PSMB8-AS1 silencing restrained cell proliferation in glioma, and the results of PSMB8-AS1 overexpression were opposite. Moreover, PSMB8-AS1 could bind with miR-574-5p, which was low expressed in glioma cells. In addition, RAB10 acted the target gene of miR-574-5p, and PSMB8-AS1 could regulate RAB10 via modulating miR-574-5p. Besides, miR-574-5p inhibitor/mimics remedied the repressive/simulative role of PSMB8-AS1 depletion/overexpression, and RAB10 downregulation/upregulation reversed the encouraging/blocked function caused by miR-574-5p inhibitor/mimics in PSMB8-AS1 depletion/overexpression transfected glioma cells. Additionally, ELK1, a transcription factor, could active PSMB8-AS1 expression. To be concluded, PSMB8-AS1 activated by ELK1 promotes cell proliferation in glioma via regulating miR-574-5p/RAB10, which may be contributory to find new targets to treat glioma.

MiR-6838-5p suppresses cell metastasis and the EMT process in triple-negative breast cancer by targeting WNT3A to inhibit the Wnt pathway

BACKGROUND

Triple-negative breast cancer (TNBC) has become a common tumor that harms women's physical and mental health, as characterized by a relatively rapid recurrence and a high incidence of brain metastasis. Research increasingly suggests that microRNAs play key roles in the progress of TNBC. However, the function of miR-6838-5p in TNBC has not yet been reported, and requires additional exploration.

METHODS

In the present study, we uncovered miR-6838-5p expression in TNBC cells via a quantitative reverse transcriptase-polymerase chain reaction. Functionally, the impacts of up-regulated or down-regulated miR-6838-5p on TNBC invasiveness, Wnt pathway activation and epithelial-mesenchymal transition (EMT) were investigated via transwell and western blot assays. Mechanical analyses were utilized to unmask the miR-6838-5p mechanism in TNBC, including luciferase reporter, western blot and RIP assays. Rescue assays manifested the miR-6838-5p/WNT3A network in TNBC invasiveness through the Wnt pathway.

RESULTS

Under-expressed miR-6838-5p was found in TNBC cells. Up-regulation of miR-6838-5p suppressed TNBC cell invasion, migration and blockade of the Wnt pathway. However, down-regulation of miR-6838-5p led to opposite results. Furthermore, we found, via luciferase reporter, western blot and RIP assays, that miR-6838-5p could bind with WNT3A and negatively regulate WNT3A expression. Through rescue experiments, we demonstrated that the overexpression of WNT3A partially rescued the miR-6838-5p overexpression-mediated inhibitory effect, and knockdown of WNT3A partially rescued the miR-6838-5p suppression-mediated promotive effect on the progression of TNBC.

CONCLUSIONS

In summary, the results of the present study indicate that miR-6838-5p suppresses cell proliferation, metastasis and the EMT process in TNBC by targeting WNT3A to inhibit the Wnt pathway, which may provide a new insight into the therapeutic strategies of TNBC.

Plasma miR-32 levels in non-small cell lung cancer patients receiving platinum-based chemotherapy can predict the effectiveness and prognosis of chemotherapy

BACKGROUND

Previous studies have shown that microRNA-32 (miRNA-32) is an exosome microRNA that affects the proliferation and metastasis of non-small cell lung cancer (NSCLC) cells. In this study, our goal was to assess the expression of plasma microRNA-32 and its potential as a biomarker to predict the tumor response and survival of patients with NSCLC undergoing platinum-based chemotherapy.

METHODS

Plasma microRNA-32 levels before and after 1 cycle of platinum-based chemotherapy in 43 patients with NSCLC were measured using a quantitative real-time polymerase chain reaction assay (qPCR). In addition, the demographic and survival data of the patients were collected for analysis.

RESULTS

A significant correlation was observed between the changes in microRNA-32 levels before and after 1 chemotherapy cycle and the treatment response (P = .035). In addition, Kaplan-Meier analysis showed that the level of microRNA-32 after 1 chemotherapy cycle was significantly correlated with the prognosis of patients. The median progression-free survival (P = .025) and overall survival (P = .015) of patients with high microRNA-32 levels (≥7.73) after 1 chemotherapy cycle was 9 and 21 months, respectively. In contrast, the median survival of patients with low microRNA-32 levels (<7.73) was 5 and 10 months, respectively.

CONCLUSIONS

The plasma levels of microRNA-32 correlated with the efficacy of platinum-based chemotherapy and survival, indicating that microRNA-32 may be useful for predicting the effectiveness of platinum-based chemotherapy and prognosis in NSCLC.

Identification of diagnostic utility and molecular mechanisms of circulating miR-551b-5p in gastric cancer

BACKGROUND

Gastric cancer (GC) is one of the most common cancers globally leading to 850,000 deaths each year. GC patients are often diagnosed at advanced stages which results in poor prognosis. This study aimed to identify a novel circulating miRNA as the diagnostic biomarker of GC and further explore its regulatory mechanisms in GC.

MATERIALS AND METHODS

First, the candidate serum miRNA was selected after analysis of microarray data. Then, the levels of candidate miRNA in the serum of GC patients were validated in an independent cohort. The diagnostic utility of miRNA was evaluated by using receiver operating characteristic curve (ROC) analysis. The functional and pathways enrichment analysis of targets of candidate miRNA were explored by online tool DAVID.

RESULTS

After comprehensive analysis of Gene Expression Omnibus (GEO) dataset, miR-551b-5p was selected as candidate due to its highest differential fold-change. Another independent cohort showed that serum miR-551b-5p could differentiate GC patients from healthy controls (HCs) with area under the curve (AUC) of 0.84 (95%CI: 0.75-0.93). The functional and pathways enrichment analysis revealed that targets of miR-551b-5p mainly located in cytoplasm and significantly associated with regulation of ubiquitin-dependent protein catabolic process, cell division, and mRNA stability.

CONCLUSIONS

Circulating miR-551b-5p was a novel promising biomarker for the detection of GC and exploration of the molecular mechanisms of miR-551b-5p is useful to search for new therapeutic strategies of GC.

miRNA-19 promotes non-small-cell lung cancer cell proliferation via inhibiting CBX7 expression

Background

miR-19 is a critical carcinogenic miRNA that participates in important biological processes of human malignancies. CBX7 plays a key role in lung cancer development and progression. In the present study, for the first time, we investigated the correlation between miR-19 and CBX7 in non-small-cell lung cancer (NSCLC).

Methods

miR-19 expression in NSCLC tissues and lung cancer cell lines was detected using quantitative reverse transcriptase PCR (qRT-PCR). Luciferase reporter assay, qRT-PCR, Western blot, and immunohistochemical assay were conducted to identify the target reaction of miR-19 and CBX7. Moreover, the influence of miR-19 on lung cancer cell proliferation, migration, and invasion was studied including cell counting kit-8 assay, scratch assay, transwell assay, flow cytometry assay, and staining assays.

Results

miR-19 was overexpressed in NSCLC tissues and lung cancer cell lines. Luciferase reporter assay demonstrated that miR-19 could inhibit CBX7 expression via binding to the 3′-UTR of CBX7. Furthermore, miR-19 remarkably decreased CBX7 protein and mRNA expression. Additionally, overexpression of miR-19 could significantly enhance lung cancer cell proliferation and migration.

Conclusion

miR-19 functions as a tumor accelerator promoting lung cancer cell proliferation through targeting CBX7 and inhibiting its expression.

Decoding the Emerging Patterns Exhibited in Non-coding RNAs Characteristic of Lung Cancer with Regard to their Clinical Significance

Lung cancer continues to be the leading topic concerning global mortality rate caused by can-cer; it needs to be further investigated to reduce these dramatic unfavorable statistic data. Non-coding RNAs (ncRNAs) have been shown to be important cellular regulatory factors and the alteration of their expression levels has become correlated to extensive number of pathologies. Specifically, their expres-sion profiles are correlated with development and progression of lung cancer, generating great interest for further investigation. This review focuses on the complex role of non-coding RNAs, namely miR-NAs, piwi-interacting RNAs, small nucleolar RNAs, long non-coding RNAs and circular RNAs in the process of developing novel biomarkers for diagnostic and prognostic factors that can then be utilized for personalized therapies toward this devastating disease. To support the concept of personalized medi-cine, we will focus on the roles of miRNAs in lung cancer tumorigenesis, their use as diagnostic and prognostic biomarkers and their application for patient therapy.

Clusterin inhibition mediates sensitivity to chemotherapy and radiotherapy in human cancer

Since its discovery in 1983, the protein clusterin (CLU) has been isolated from almost all human tissues and fluids and linked to the development of different physiopathological processes, including carcinogenesis and tumor progression. During the last few years, several studies have shown the cytoprotective role of secretory CLU in tumor cells, inhibiting their apoptosis and enhancing their resistance to conventional treatments including hormone depletion, chemotherapy, and radiotherapy. In an effort to determine the therapeutic potential that the inhibition of this protein could have on the development of new strategies for cancer treatment, numerous studies have been carried out in this field, with results, in most cases, satisfactory but sometimes contradictory. In this document, we summarize for the first time the current knowledge of the effects that CLU inhibition has on sensitizing tumor cells to conventional cancer treatments and discuss its importance in the development of new strategies against cancer.

miRNA‑1284 inhibits cell growth and induces apoptosis of lung cancer cells

Lung cancer is the most common cancer worldwide, and morbidity and mortality associated with lung cancer has been increasing annually in recent decades. MicroRNAs (miRNAs), which are short non-coding RNA sequences that are involved in the regulation of gene expression, have been previously demonstrated to be key regulators in cancer. The present study aimed to clarify the role of miRNA (miR)-1284 in lung cancer. A549 lung carcinoma cells were transfected with miR-1284 mimic or miR-1284 inhibitor using Lipofectamine 2000. Subsequently, cell viability, growth and apoptosis of A459 cells in the miR-1284 mimic, miR-1284 inhibitor and control groups were assayed by MTT assay, bromodeoxyuridine assay and flow cytometry, respectively. Furthermore, the protein expression levels of p27, p21, Bax, pro-caspase-3, activated caspase-3 and Myc were detected by western blot analysis to investigate the molecular mechanisms underlying the effect of miR-1284 on A549 cells. The cell viability and growth of A549 cells were significantly decreased in the miR-1284 mimic group compared with the control group, whereas the percentage of apoptotic cells was significantly increased. By contrast, miR-1284 inhibitor transfection significantly increased the cell viability and growth compared with control, and decreased apoptosis. Furthermore, expression of p27 was increased in miR-1284 mimic-transfected A549 cells compared with the control group, whereas p21 was unaffected by miR-1284 overexpression or inhibition. The expression of Myc was decreased by miR-1284 mimic transfection compared with the control group. For the other apoptosis-associated proteins that were investigated (Bax, pro-caspase-3 and active caspase-3), the expression levels in the miR-1284 mimic transfected cells were higher than in the other two groups (control and miR-1284 inhibitor). In conclusion, the results suggest that miR-1284 affects cell proliferation and apoptosis of lung cancer cells, indicating that miR-1284 may have a key role in lung tumorigenesis.

MiR-375/SLC7A11 axis regulates oral squamous cell carcinoma proliferation and invasion

We aimed to detect the functions of miR‐375/SLC7A11 axis on oral squamous cell carcinoma (OSCC) cell proliferation and invasion. Expression levels of miR‐375 and SLC7A11 in OSCC tissues and cells were measured with RT‐qPCR and western blot. Targeting site was predicted by TargetScan and confirmed by dual luciferase reporting assay. By way of manipulating the expression level of miR‐375 and SLC7A11 in CAL‐27 and Tca8113 cell lines, the cell biological abilities were evaluated. MTT, colony formation, Transwell, wound healing assays and flow cytometry were used to detect OSCC cell viability, proliferation, invasion, migration and apoptosis, respectively. MiR‐375 was significantly downregulated in OSCC tissues and cells compared to adjacent tissue and normal oral cell line respectively while SLC7A11 was upregulated. Targeting relationship was verified by luciferase reporting assay, and miR‐375 could effectively suppress SLC7A11 level in OSCC cells. Replenishing of miR‐375 significantly repressed OSCC cell viability, proliferation, invasion and migration and induced cell apoptosis and G1/G0 arrest. Overexpression of SLC7A11 recovered those biological abilities in miR‐375 upregulated cells. Collective data suggested that miR‐375 served as a tumor suppressor via regulating SLC7A11. Replenishing of miR‐375 or knockout of SLC7A11 could be therapeutically exploited.

Expression of serum microRNA-378 and its clinical significance in renal cell carcinoma

Studies have demonstrated that miRNA-378 is expressed in various malignant tumors. In the present study, we aimed to explore the expression of serum miRNA-378 and its clinical significance in renal cell carcinoma (RCC) patients. A total of 75 RCC patients, 63 renal cysts (RC) patients and 75 healthy controls were selected. The miRNA-378 level in RCC and RC groups was significantly higher than in healthy control group, with RCC group having the highest level. The miRNA-378 levels were significantly decreased within the same group after surgery. When compared with healthy controls, RC group had higher levels but not significantly (p > 0.05) while levels in RCC group were significantly higher (p < 0.05). miRNA-378 expression was correlated with clinical stage and differentiation degree, but not correlated with patient's age, gender, surgical strategy and tumor diameter. The AUC of miRNA-378 was 0.896, 95% confidence interval was 0.847 to 0.945, and AUC hypothesis testing was statistically significant (p < 0.001, RCC vs healthy control). miRNA-378 shows potential in the diagnosis and prediction of postoperative curative effect of renal cell carcinoma, but further studies with lager samples are needed.

MicroRNA-378 enhances inhibitory effect of curcumin on glioblastoma

Glioblastoma multiforme is the most aggressive and common primary brain tumor, and is virtually incurable due to its therapeutic resistance to radiation and chemotherapy. Curcumin is a well-known phytochemical exhibiting antitumor activity on many human cancers including glioblastoma multiforme. Given the unique miRNA expression profiles in cancer cells compared to non-cancerous cells, we investigated whether these miRNA could be used to cancer therapy. In this report we show that miR-378, a glioblastoma multiforme down regulated miRNA, may enhance the inhibitory effect of curcumin on this cancer growth. Our results indicated that the inhibitory effect of curcumin was enhanced in miR-378-expressing stable U87 cells in vitro and in vivo, compared to control cells. MiR-378 was found to target p-p38 expression, underlying the observed phenotypic changes. Thus, we concluded that miR-378 enhances the response of glioblastoma multiforme to curcumin treatment, by targeting p38.

Expression and mechanism of action of miR-196a in epithelial ovarian cancer

OBJECTIVE

To explore the expression, biological function and possible mechanism of action of microRNA molecular-196a (miR-196a) in epithelial ovarian cancer.

METHODS

RT-PCR was used to detect the expression quantities of epithelial ovarian tissue, benign ovarian tissue, normal ovary epithelial tissue, ovarian cancer cell lines and miR-196a in normal ovarian epithelial cells to analyze the relationship between the expression of miR-196a and the clinical pathologic parameters of ovarian cancer. Among those cell lines, the cell line of which miR-196a expressed the most or least was selected and transfected the ovarian cancer cell line by using negative control plasma and miR-196a inhibitor. After transfection, RT-PCR was used to test the expression quantity of miR-196a, Transwell chamber method was applied to determine the migration and invasion abilities of ovarian carcinoma cells and Western blot was employed to detect the expression of HOXA10 protein.

RESULTS

The relative expression quantities of miR-196a in ovarian cancer tissue and benign ovarian tissue were significantly higher than that in normal ovarian epithelial tissue, and the expression quantity of miR-196a in ovarian cancer tissue was distinctively higher than that in benign ovarian tissue (P < 0.05). Among 78 cases of epithelial ovarian cancer, the expression quantities of miR-196a in patients with low differentiation were all significantly higher than those in patients with high differentiation (P < 0.05). The expression of miR-196a showed no significant relation with age, clinical stage and whether CA125 was positive or not in patients (P > 0.05). Compared with normal ovarian epithelial cell line IOSE80, the expression quantities of miR-196a of all ovarian cancer cell lines increased obviously and differences were statistically significant (P < 0.05). Among them, the expression of miR-196a of ovarian cancer cell line SKOV3 was the highest, while it decreased significantly (4.678 ± 0.785 vs. 2.131 ± 0.345, t = 2.938, P < 0.05) after the ovarian cancer cell line SKOV3 was transfected by miR-196a inhibitor. The results of Transwell chamber method showed that the migration and invasion abilities of ovarian cancer cells SKOV3 were declined significantly after the expression of miR-196a was down-regulated and the difference showed statistical significance (P < 0.05). The results of Western blot revealed that the relative expression of HOXA10 decreased distinctly after the expression of miR-196a was down-regulated and also the difference showed statistical significance (P < 0.05).

CONCLUSIONS

The miR-196a might serve as a cancer-promoting gene to promote the migration and invasion of epithelial ovarian cancer by downstream target gene HOXA10.

MiR-378 suppresses prostate cancer cell growth through downregulation of MAPK1 in vitro and in vivo

Prostate cancer is one of the biggest health problems for the aging male. To the present, the roles of dysregulated microRNAs in prostate cancer are still unclear. Here, we evaluated the anti-proliferative role of miR-378 in prostate cancer. And, we found that the expression of miR-378 was significantly downregulated in clinical prostate cancer tissues. In vitro assay suggested that overexpression of miR-378-suppressed prostate cancer cell migration and invasion promoted cell apoptosis. Furthermore, we identified and validated MAPK1 as a direct target of miR-378. Ectopic expression of MAPK1 rescues miR-378-suppressed cell migration and invasion. In vivo assay demonstrated that the stably miR-378-overexpressed prostate cancer cells displayed a significantly reduction in tumor growth. Taken together, our data suggested that miR-378 may act as a potential therapeutic target against human prostate cancer.