Elevated expression of tumor miR-222 in pancreatic cancer is associated with Ki67 and poor prognosis

The Prognostic Importance of Ki-67 in Gastrointestinal Carcinomas: A Meta-analysis and Multi-omics Approach

PURPOSE

This study aimed to determine if Ki-67, a commonly used marker to measure tumor proliferation, is a reliable prognostic factor in various types of gastrointestinal (GI) cancers based on current high-quality multivariable evidence.

METHODS

A comprehensive search was conducted in PubMed, Embase, Scopus, and ISI Web of Science databases to investigate the association between Ki-67 positivity and overall survival (OS) and disease/recurrence-free survival (DFS/RFS) in GI cancers. Heterogeneity was assessed using Chi-square-based Q and I2 analyses and publication bias using funnel plots and Egger's analysis. In addition, Ki-67 levels in different GI cancers were examined by different platforms. The prognostic capability of Ki-67, gene ontology (GO), and pathway enrichment analysis were obtained from GEPIA2 and STRING.

RESULTS

Totally, 61 studies, involving 13,034 patients, were deemed eligible for our evaluation. The combined hazard ratios (HRs) demonstrated the prediction ability of overexpressed Ki-67 for a worse OS (HR: 1.67, P < 0.001; HR: 1.37, P = 0.021) and DFS/RFS (HR: 2.06, P < 0.001) in hepatocellular and pancreatic malignancies, respectively, as confirmed by multi-omics databases. However, similar correlation was not found in esophageal, gastric, and colorectal cancers. Furthermore, most of the associations were identified to be robust based on different subcategories and publication bias assessment. Finally, enriched Ki-67-related genes were found to be involved in various important signaling pathways, such as cell cycle, P53 signaling network, and DNA damage responses.

CONCLUSION

This study supports that Ki-67 can serve as an independent prognostic biomarker for pancreatic and hepatocellular malignancies in clinical settings.

Circulating MicroRNAs as Noninvasive Diagnostic and Prognostic Biomarkers in Pancreatic Cancer: A Review

Pancreatic cancer (PC) is one of the most lethal human cancers. Currently, most PC cases are diagnosed at an already advanced stage. Early detection of PC is critical to improving survival rates. Therefore, there is an urgent need to identify biomarkers for the early detection of PC. Recently, circulating miRNAs in whole blood and other body fluids have been reported as promising biomarkers for the early detection of various cancers, including PC. Furthermore, due to minimal invasiveness and technical availability, circulating miRNAs hold promise for further wide usage. As a potential novel molecular marker, circulating miRNAs not only represent promising noninvasive diagnostic and prognostic tools but could also improve the evaluation of tumor classification, metastasis, and curative effect. The purpose of this review is to outline the available information regarding circulating miRNAs as biomarkers for the early detection of PC.

Preliminary study on miRNA in prostate cancer

OBJECTIVE

To screen for miRNAs differentially expressed in prostate cancer and prostate hyperplasia tissues and to validate their association with prostate cancer.

METHODS

Patients diagnosed by pathology in the Department of Urology of the First Affiliated Hospital of Xinjiang Medical University from October 2021 to June 2022 were selected, and their general clinical information, blood samples, and prostate tissue samples were collected. miRNA microarray technology was performed to obtain differentially expressed miRNAs in prostate cancer and hyperplasia tissues, and miRNAs to be studied were screened by microarray results and review of relevant literature. The detection of miRNA expression in the patients' blood and prostate tissue samples was measured. The miRNA-222-mimics were transfected into PC3 cells, and cell biology experiments such as CCK8, scratch, Transwell, and flow cytometry were performed to detect the effects of overexpressed miRNA-222 on the growth and proliferation, invasive ability, apoptotic ability, and metastatic ability of prostate cancer cells.

RESULTS

The results of the miRNA microarray showed that there were many differentially expressed miRNAs in prostate cancer and hyperplasia tissues, and four miRNAs, miRNA-144, miRNA-222, miRNA-1248, and miRNA-3651 were finally selected as the subjects by reviewing relevant literature. The results showed that the expression of miRNA-222 in prostate cancer tissues was lower than that in prostate hyperplasia tissues (P < 0.05). The expression of miRNA-222, miRNA-1248, and miRNA-3651 in blood samples of prostate cancer patients was lower than that in prostate hyperplasia patients (P < 0.05). The analysis results indicated that the f/t ratio and the relative expression of miRNA-222 and miRNA-1248 were independent influences of prostate cancer (P < 0.05), in which overexpression of miRNA-222 decreased the proliferative, invasive, and metastatic abilities of PC3 cells and enhanced the level of apoptosis of cancer cells.

CONCLUSIONS

Although there was no significant change in the overall incidence of prostate cancer in this study, significant changes occurred in the incidence of prostate cancer with different characteristics. In addition, the nomogram prediction model of prostate cancer-specific survival rate constructed based on four factors has a high reference value, which helps physicians to correctly assess the patient-specific survival rate and provides a reference basis for patient diagnosis and prognosis evaluation.

Study of the antioxidant and anti-pancreatic cancer activities of Anchusa strigosa aqueous extracts obtained by maceration and ultrasonic extraction techniques

Pancreatic cancer is a highly aggressive malignancy and a leading cause of cancer-related deaths worldwide. Moreover, the incidence and mortality rates for pancreatic cancer are projected to keep increasing. A major challenge in the treatment of pancreatic cancer is the lack of effective screening approaches, which contributes to its poor prognosis, indicating the need for new treatment regimens and alternative therapies, such as herbal medicine. The medicinal plant A. strigosa, which is widely distributed in the Eastern Mediterranean region, is a short prickly plant from the Boraginaceae family that has been widely used in traditional medicine for treating various diseases. Nevertheless, its effect on human pancreatic cancer remains poorly investigated. In the present study, we screened the phytochemical content of Anchusa strigosa aqueous extracts obtained by maceration and ultrasound-assisted methods (ASM and ASU, respectively) and evaluated their antioxidant effects. We also investigated their anticancer effects and possible underlying mechanisms. The results show that both extracts were rich in bioactive molecules, with slight differences in their composition. Both extracts exhibited remarkable antioxidant potential and potent radical-scavenging activity in vitro. Additionally, non-cytotoxic concentrations of both extracts attenuated cell proliferation in a time- and concentration-dependent manner, which was associated with a decrease in the proliferation marker Ki67 and an induction of the intrinsic apoptotic pathway. Furthermore, the extracts increased the aggregation of pancreatic cancer cells and reduced their migratory potential, with a concomitant downregulation of integrin β1. Finally, we showed that the ASM extract caused a significant decrease in the levels of COX-2, an enzyme that has been linked to inflammation, carcinogenesis, tumor progression, and metastasis. Taken together, our findings provide evidence that A. strigosa extracts, particularly the extract obtained using the maceration method, have a potential anticancer effect and may represent a new resource for the design of novel drugs against pancreatic cancer.

Alteration in Levels of Specific miRNAs and Their Potential Protein Targets between Human Pancreatic Cancer Samples, Adjacent Normal Tissue, and Xenografts Derived from These Tumors

Herein, we describe the global comparison of miRNAs in human pancreatic cancer tumors, adjacent normal tissue, and matched patient-derived xenograft models using microarray screening. RNA was extracted from seven tumor, five adjacent normal, and eight FI PDX tumor samples and analyzed by Affymetrix GeneChip miRNA 4.0 array. A transcriptome analysis console (TAC) was used to generate comparative lists of up- and downregulated miRNAs for the comparisons, tumor vs. normal and F1 PDX vs. tumor. Particular attention was paid to miRNAs that were changed in the same direction in both comparisons. We identified the involvement in pancreatic tumor tissue of several miRNAs, including miR4534, miR3154, and miR4742, not previously highlighted as being involved in this type of cancer. Investigation in the parallel mRNA and protein lists from the same samples allowed the elimination of proteins where altered expression correlated with corresponding mRNA levels and was thus less likely to be miRNA regulated. Using the remaining differential expression protein lists for proteins predicted to be targeted for differentially expressed miRNA on our list, we were able to tentatively ascribe specific protein changes to individual miRNA. Particularly interesting target proteins for miRs 615-3p, 2467-3p, 4742-5p, 509-5p, and 605-3p were identified. Prominent among the protein targets are enzymes involved in aldehyde metabolism and membrane transport and trafficking. These results may help to uncover vulnerabilities that could enable novel approaches to treating pancreatic cancer.

Regulation of CDK inhibitor p27 by microRNA 222 in breast cancer patients

BACKGROUND

Breast cancer is the most common of all cancers and the second leading cause of cancer-related deaths among women worldwide. MicroRNAs regulate at least 60% of the human genes, including tumor suppressor genes and oncogenes, and can thereby affect cancer risk. In this study, the prognostic values of the CDK inhibitor p27 and miR-222 as biomarkers for breast cancer were evaluated.

METHODS

The real-time quantitative polymerase chain reaction method was employed to measure the expression level of miR-222, whereas the serum levels of the CDK inhibitor p27 were measured via enzyme-linked immunosorbent assay. The levels were determined in sera from 110 participants representing three different groups.

RESULTS

Patients with breast cancer exhibited significantly higher expression levels of miR-222 and lower levels of CDK inhibitor p27 than the control group. In addition, a statistically significant inverse correlation between miR-222 and the CDK inhibitor p27 was observed. The receiver operating characteristic curves plotted for serum p27 and miR-222 helped in significantly differentiating between breast cancer patients and controls but could not discriminate between those with stage II and stage III cancer.

CONCLUSION

Thus, a significant upregulation in the serum miR-222 levels was observed in cancer patients, and a significant inverse correlation was noted between the miR-222 and CDK inhibitor p27 expression levels. These findings indicate that miR-222 may be used as a useful noninvasive screening biomarker for human breast cancer.

MICROABSTRACT

Novel biomarkers for prognosis, prediction, and therapeutic purposes are essential as the prognosis and therapeutic targets of breast cancer are dependent on traditional markers, such as the tumor stage and hormonal receptor status. This study aimed to evaluate the diagnostic and prognostic values of the CDK inhibitor p27 and miR-222 in breast cancer. Our results indicated that miR-222 and the CDK inhibitor p27 may be used as noninvasive biomarkers to screen for human breast cancer but cannot discriminate between patients with early breast cancer and patients with advanced breast cancer.

Plasma miRNA Biomarkers in Limited Volume Samples for Detection of Early-stage Pancreatic Cancer

Early detection of pancreatic ductal adenocarcinoma (PDAC) is key to improving patient outcomes; however, PDAC is usually diagnosed late. Therefore, blood-based minimally invasive biomarker assays for limited volume clinical samples are urgently needed. A novel miRNA profiling platform (Abcam Fireplex-Oncology Panel) was used to investigate the feasibility of developing early detection miRNA biomarkers with 20 μL plasma from a training set (58 stage II PDAC cases and 30 controls) and two validation sets (34 stage II PDAC cases and 25 controls; 44 stage II PDAC cases and 18 controls). miR-34a-5p [AUC = 0.77; 95% confidence interval (CI), 0.66-0.87], miR-130a-3p (AUC = 0.74; 95% CI, 0.63-0.84), and miR-222-3p (AUC = 0.70; 95% CI, 0.58-0.81) were identified as significantly differentially abundant in plasma from stage II PDAC versus controls. Although none of the miRNAs individually outperformed the currently used serologic biomarker for PDAC, carbohydrate antigen 19-9 (CA19-9), combining the miRNAs with CA 19-9 improved AUCs from 0.89 (95% CI, 0.81-0.95) for CA 19-9 alone to 0.92 (95% CI, 0.86-0.97), 0.94 (95% CI, 0.89-0.98), and 0.92 (95% CI, 0.87-0.97), respectively. Gene set enrichment analyses of transcripts correlated with high and low expression of the three miRNAs in The Cancer Genome Atlas PDAC sample set. These miRNA biomarkers, assayed in limited volume plasma together with CA19-9, discriminate stage II PDAC from controls with good sensitivity and specificity. Unbiased profiling of larger cohorts should help develop an informative early detection biomarker assay for diagnostic settings. PREVENTION RELEVANCE: Development of minimally invasive biomarker assays for detection of premalignant disease and early-stage pancreatic cancer is key to improving patient survival. This study describes a limited volume plasma miRNA biomarker assay that can detect early-stage resectable pancreatic cancer in clinical samples necessary for effective prevention and clinical intervention.

Crosstalk between miRNAs and signaling pathways involved in pancreatic cancer and pancreatic ductal adenocarcinoma

Pancreatic cancer (PC) is the seventh leading cause of cancer-related deaths worldwide with 5-year survival rates below 8%. Most patients with PC and pancreatic ductal adenocarcinoma (PDAC) die after relapse and cancer progression as well as resistance to treatment. Pancreatic tumors contain a high desmoplastic stroma that forms a rigid mass and has a potential role in tumor growth and metastasis. PC initiates from intraepithelial neoplasia lesions leading to invasive cancer through various pathways. These lesions harbor particular changes in signaling pathways involved in the tumorigenesis process. These events affect both the epithelial cells, including the tumor and the surrounding stroma, and eventually lead to the formation of complex signaling networks. Genetic studies of PC have revealed common molecular features such as the presence of mutations in KRAS gene in more than 90% of patients, as well as the inactivation or deletion mutations of some tumor suppressor genes including TP53, CDKN2A, and SMAD4. In recent years, studies have also identified different roles of microRNAs in PC pathogenesis as well as their importance in PC diagnosis and treatment, and their involvement in various signaling pathways. In this study, we discussed the most common pathways involved in PC and PDAC as well as their role in tumorigenesis and progression. Furthermore, the miRNAs participating in the regulation of these signaling pathways in PC progression are summarized in this study. Therefore, understanding more about pathways involved in PC can help with the development of new and effective therapies in the future.

An increased level of MiR-222-3p is associated with TMP2 suppression, ERK activation and is associated with metastasis and a poor prognosis in renal clear cell carcinoma

OBJECTIVE

Renal cell carcinoma (RCC) is the most common malignancy involving the kidneys and a major cause of cancer mortality. The involvement of microRNA (miRNA) expression in the tumorigenesis and progression of RCC still not been previously highlighted. We aimed to explore the potential role of miR-222-3p in renal cell carcinoma (RCC).

METHOD

We first found that miR-222-3p was elevated significantly in the RCC tissues as compared to the non-tumor counterparts. We also found that a higher level of miR-222-3p in different RCC cell lines than the HK-2 cells.

RESULTS

In vitro validation experiment using miR-222-3p mimic molecules significantly induced expression of EMT marker vimentin and downregulated E-cadherin in both 769-P and 786-O RCC cells. In contrary, when miR-222-3p was downregulated by its inhibitor, the reverse observations were made. We then demonstrated a reversal association between the expression level of miR-222-3p and TIMP2/ERK where TIMP2 functions as a tumor suppressor. In a small cohort of 45 clinical samples, we found that miR-222-3p expression level was elevated and was associated with a poorer survival of the patients. Patients with higher miR-222-3p expression showed had a statistically shorter overall survival than those patients of lower miR-222-3p level (HR, 5.789; p= 0.02).

CONCLUSION

Collectively, we showed that miR-222-3p functioned as a tumor progression marker and could be a target for future drug development.

Prognostic value of microRNAs in pancreatic cancer: a meta-analysis

BACKGROUND

The prognostic impact of microRNA (miRNA) expression levels in pancreatic cancer (PC) has been estimated for years, but the outcomes are controversial and heterogeneous. Therefore, we comprehensively reviewed the evidence collected on miRNA expression in PC to determine this effect.

RESULTS

PC patients with high miR-21 (HR=2.61, 95%CI=1.68-4.04), miR-451a (HR=2.23, 95%CI=1.23-4.04) or miR-1290 (HR=1.43, 95%CI=1.04-1.95) levels in blood had significantly poorer OS (P<0.05). Furthermore, PC patients with high miR-10b (HR=1.73, 95%CI=1.09-2.76), miR-17-5p (HR=1.91, 95%CI=1.30-2.80), miR-21 (HR=1.90, 95%CI=1.61-2.25), miR-23a (HR=2.18, 95%CI=1.52-3.13), miR-155 (HR=2.22, 95%CI=1.27-3.88), miR-203 (HR=1.65, 95%CI=1.14-2.40), miR-221 (HR=1.72, 95%CI=1.08-2.74), miR-222 levels (HR=1.72, 95%CI=1.02-2.91) or low miR-29c (HR=1.39, 95%CI=1.08-1.79), miR-126 (HR=1.55, 95%CI=1.23-1.95), miR-218 (HR=2.62, 95%CI=1.41-4.88) levels in tissues had significantly shorter OS (P<0.05).

CONCLUSIONS

In summary, blood miR-21, miR-451a, miR-1290 and tissue miR-10b, miR-17-5p, miR-21, miR-23a, miR-29c, miR-126, miR-155, miR-203, miR-218, miR-221, miR-222 had significant prognostic value.

METHODS

We searched PubMed, EMBASE, Web of Science and Cochrane Database of Systematic Reviews to recognize eligible studies, and 57 studies comprising 5445 PC patients and 15 miRNAs were included to evaluate the associations between miRNA expression levels and overall survival (OS) up to June 1, 2019. Summary hazard ratios (HR) with 95% confidence intervals (CI) were calculated to assess the effect.

Role of miR-221/222 in Tumor Development and the Underlying Mechanism

MicroRNA-221/222 (miRNA-221/222, miR-221/222) is a noncoding microRNA which is widely distributed in eukaryotic organisms and deeply involved in the posttranscriptional regulation of gene expressions. According to recent studies, abnormal expressions of miR-221/222 are closely related to the occurrence and development of various kinds of malignant tumors. The role of miR-221/222 in tumor development and their potential molecular mechanism in various cancers, including liver cancer, colorectal cancer, cervical cancer, ovarian cancer, and endometrial carcinoma, are summarized and reviewed in this paper. Moreover, the potential translational biomarker role of abnormal miR-221/222 level in tumor or blood circulation for tumor diagnosis is also discussed.

Role of TGF-β/Smad Pathway in the Transcription of Pancreas-Specific Genes During Beta Cell Differentiation

Autoimmune destruction of pancreatic beta cells causes absolute insulin deficiency and results in type 1 diabetes mellitus (T1DM). The substitution of healthy pancreatic beta cells for damaged cells would be the ideal treatment for T1DM; thus, the generation of pancreatic beta cells from adult stem cells represents an attractive avenue for research. In this study, a cocktail of factors was used to induce the differentiation of pancreatic beta cells from mesenchymal stem cells (MSCs). The differentiation program was divided into five stages, and the roles of the cocktail factors used during each stage were systematically elucidated. Activin A was found to phosphorylate Smad2 and Smad3 in stage III, thereby activating the TGF-β/Smad pathway. Meanwhile, the endocrine-specific transcription factor, Ngn3, and the pancreas-specific miRNAs, miR-375 and miR-26a, were dramatically elevated in stage III. We next demonstrated that Smad4, an important transcription factor in the TGF-β/Smad pathway, could bind to the promoter sequences of target genes and enhance their transcription to initiate the differentiation of beta cells. Use of SB-431542, an inhibitor of the TGF-β/Smad pathway, demonstrated in vivo and in vitro that this pathway plays a critical role in the production of pancreatic beta cells and in modulating insulin secretion. Thus, the TGF-β/Smad pathway is involved in the production of beta cells from adult stem cells by enhancing the transcription of Ngn3, miR-375, and miR-26a. These findings further underline the significant promise of cell transplant therapies for type 1 diabetes mellitus.

Silencing microRNA-221/222 cluster suppresses glioblastoma angiogenesis by suppressor of cytokine signaling-3-dependent JAK/STAT pathway

Angiogenesis is a major pathologic characteristic of glioblastoma, which is one aggressive primary brain tumor. MicroRNA-221/222 (miR-221/222) cluster has been previously reported to function importantly in malignant glioma biological process. The current study aims at evaluating the effects of miR-221/222 cluster on angiogenesis of glioblastoma cells. Microarray data were analyzed to select glioblastoma-associated differentially expressed genes, and dual-luciferase reporter assay was performed to assess targeting correlation between miR-221/222 cluster and suppressor of cytokine signaling-3 (SOCS3). Subsequently, the expression patterns of miR-221 and miR-222 in glioblastoma cells were identified. miR-221 and miR-222 were overexpressed or silenced in glioblastoma cells to identify the effect of miR-221/222 cluster in cell invasion, migration, proliferation, and angiogenesis. To define downstream pathway of miR-221/222 cluster or SOCS3 in glioblastoma, levels of Janus kinase (JAK)/signal transducers and activators of transcription (STAT) pathway-related proteins were assessed. Additionally, the functions of miR-221/222 on glioblastoma cell angiogenesis were measured in vivo with microvessel density assayed. miR-221 and miR-222 were expressed at a high level and SOCS3 was at a low level in glioblastoma. Downregulation of the miR-221/222 cluster diminished the invasion, migration, proliferation, and angiogenesis with reduced protein levels of matrix metalloproteinase-2 (MMP-2), MMP-9, and vascular endothelial growth factor in glioblastoma cells. Also, silencing miR-221/222 cluster reduced p-JAK2/JAK2 and p-STAT3/STAT3. Consistently, the inhibitory role of silencing miR-221/222 cluster on tumorigenesis of glioblastoma cells was confirmed in vivo. Collectively, the inhibition of miR-221/222 cluster could attenuate the glioblastoma angiogenesis through inactivation of the JAK/STAT pathway by upregulating SOCS3.

Prognostic Role of miR-221 and miR-222 Expression in Cancer Patients: A Systematic Review and Meta-Analysis

Background: A wealth of evidence has shown that microRNAs (miRNAs) can modulate specific genes, increasing our knowledge on the fine-tuning regulation of protein expression. miR-221 and miR-222 have been frequently identified as deregulated across different cancer types; however, their prognostic significance in cancer remains controversial. In view of these considerations, we performed an updated systematic review and meta-analysis of published data investigating the effects of miR-221/222 on overall survival (OS) and other secondary outcomes among cancer patients. A systematic search of PubMed, Web of Knowledge, and Cochrane Library databases was performed. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were used to assess the strength of association. Results: Fifty studies, analyzing 6086 patients, were included in the systematic review. Twenty-five studies for miR-221 and 17 studies for miR-222 which assessed OS were included in the meta-analysis. High expression of miR-221 and miR-222 significantly predicted poor OS (HR: 1.48, 95% CI: 1.14–1.93, p = 0.003 and HR: 1.90, 95% CI: 1.43–2.54, p < 0.001, respectively). Subgroup analysis revealed that the finding on miR-221 was not as robust as the one on miR-222. Furthermore, high miR-222 expression was also associated with worse progression-free survival and disease-free survival pooled with recurrence-free survival. Conclusions: The meta-analysis demonstrated that high expression of miR-222 is associated with poor prognosis in cancer patients, whereas the significance of miR-221 remains unclear. More work is required to fully elucidate the role of miR-221 and miR-222 in cancer prognosis, particularly in view of the limitations of existing results, including the significant heterogeneity and limited number of studies for some cancers.

miR-19b-3p promotes human pancreatic cancer Capan-2 cells proliferation by targeting phosphatase and tension homolog

Background

Pancreatic cancer is a common cancer with a poor prognosis and an increasing morbidity. miR-19b-3p has been implicated in some cancers, however, its role in pancreatic cancer is unclear.

Methods

Human pancreatic cancer cell line Capan-2 cells were transfected with miR-19b-3p mimic and inhibitor. Cell proliferation was measured by 5-Ethynyl-2'-deoxyuridine (EdU) staining assays. Cell cycle of Capan-2 cells was examined by flow cytometry. The expression of phosphatase and tension homolog (PTEN) was determined by real-time quantitative polymerase chain reaction (PCR) and western blotting analysis. Functional rescue experiments were performed through PTEN overexpression and miR-19b-3p mimic by using EdU staining assays.

Results

miR-19b-3p mimic significantly increased miR-19b-3p while miR-19b-3p inhibitor decreased that. EdU staining showed that miR-19b-3p overexpression promoted Capan-2 cells proliferation while miR-19b-3p inhibition decreased that. Flow cytometry analysis of cell cycle indicated that miR-19b-3p overexpression increased the percentage of Capan-2 cells in S phase while miR-19b-3p inhibition decreased that. PTEN was confirmed to be a target gene of miR-19b-3p and PTEN overexpression eliminated the pro-proliferation effects of miR-19b-3p in Capan-2 cells.

Conclusions

Our study demonstrates that miR-19b-3p promotes Capan-2 cells proliferation by targeting PTEN.

Outcome of head compared to body and tail pancreatic cancer: a systematic review and meta-analysis of 93 studies

Background

Even when resectable pancreatic cancer (PC) is associated with a dismal prognosis. Initial presentation varies according with primary tumor location. Aim of this systematic review and meta-analysis was to evaluate the prognosis associated with site (head versus body/tail) in patients with PC.

Methods

We searched PubMed, Cochrane Library, SCOPUS, Web of Science, EMBASE, Google Scholar, LILACS, and CINAHL databases from inception to March 2018. Studies reporting information on the independent prognostic role of site in PC and comparing overall survival (OS) in head versus body/tail tumors were selected. Data were aggregated using hazard ratios (HRs) for OS of head versus body/tail PC according to fixed- or random-effect model.

Results

A total of 93 studies including 254,429 patients were identified. Long-term prognosis of head was better than body/tail cancers (HR =0.96, 95% CI: 0.92-0.99; P=0.02). A pooled HR of 0.95 (95% CI: 0.92-0.99, P=0.02) from multivariate analysis only (n=77 publications) showed that head site was an independent prognostic factor for survival.

Conclusions

Primary tumor location in the head of the pancreas at the time of diagnosis is a predictor of better survival. Such indicator should be acknowledged when designing future studies, in particular in the operable and neoadjuvant setting.

Downregulation of miR-222-3p Reverses Doxorubicin-Resistance in LoVo Cells Through Upregulating Forkhead Box Protein P2 (FOXP2) Protein

BACKGROUND Doxorubicin (DOX) is a potent chemotherapeutic agent used to treat colon cancer. Despite impressive initial clinical responses, drug resistance has dramatically compromised the effectiveness of DOX. However, the underlying mechanisms of chemotherapeutic resistance in colon cancer remain poorly understood. MATERIAL AND METHODS In this study, we compared the expression of miR-222-3p in DOX-resistant colon cancer cells (LoVo/ADR) with the corresponding DOX-sensitive parental cells (LoVo/S) using quantitative real-time PCR. In addition, miR-222-3p inhibitors were infected into LoVo/ADR cell lines and the effects of this treatment were assessed. The Cell Counting Kit 8 assay was employed to verify the sensitivity of colon cancer cell lines to DOX. EdU (5-ethynyl-2'-deoxyuridine) assay, flow cytometry, and in vivo subcutaneous tumorigenesis were used to assess cell proliferation and apoptosis. Transwell and wound healing assays were used to investigate cell migration after adding DOX. Additionally, the expression of forkhead box protein P2 (FOXP2), P-glycoprotein (P-gp) and caspase pathway-associated markers was assessed by western blotting. RESULTS Our results showed that miR-222-3p was upregulated in LoVo/ADR compared with the expression in LoVo/S cells. Additionally, downregulation of miR-222-3p in LoVo/ADR cells increased their sensitivity to DOX, reduced P-gp expression, and activated the caspase pathway. However, the downregulation of FOXP2 could efficiently reverse the effect of miR-222-3p inhibitors on LoVo/ADR cells. CONCLUSIONS Taken together, our results showed that miR-222-3p induced DOX resistance via suppressing FOXP2, upregulating P-gp, and inhibiting the caspase pathway.

MicroRNA‑222‑3p promotes tumor cell migration and invasion and inhibits apoptosis, and is correlated with an unfavorable prognosis of patients with renal cell carcinoma

The aim of the present study was to investigate the role of microRNA (miR)‑222‑3p in renal cell carcinoma (RCC). The expression level of miR‑222‑3p was detected in RCC tissues and cell lines (ACHN, 786‑O, Caki‑1 and 769‑P) and was identified to be significantly upregulated compared with the level in adjacent normal renal tissues and HK‑2 cells. Further in vitro experiments demonstrated that the over-expression of miR‑222‑3p promoted the migration and invasion, and attenuated the apoptosis of 786‑O cells, whereas the knockdown of miR‑222‑3p suppressed the migration and invasion and induced the apoptosis of 786‑O cells. Similar results were observed in the ACHN cell line in terms of migration, invasion and apoptosis. Furthermore, the expression level of miR‑222‑3p was measured in 42 RCC formaldehyde‑fixed paraffin‑embedded samples, and the association between the expression of miR‑222‑3p and the pathological characteristics and overall survival rate of patients with RCC was analyzed. The results demonstrated that patients with a higher expression of miR‑222‑3p had a significantly lower overall survival rate, compared with those with a lower expression of miR‑222‑3p [hazard ratio (HR)=5.120; P=0.036]. Multivariate analysis identified that patients with a higher expression of miR‑222‑3p retained the statistically significant decrease in overall survival rate compared with patients with a lower expression of miR‑222‑3p (HR=5.636; P=0.030). Furthermore, Kaplan‑Meier survival curves indicated that patients with higher miR‑222‑3p had significantly lower overall survival rates compared with patients with lower miR‑222‑3p (P=0.020). Taken together, these results suggested that miR‑222‑3p serves as an onco‑miR in RCC and may be a potential prognostic biomarker and therapeutic target in patients with RCC.

Downregulation of miR-183 inhibits the growth of PANC-1 pancreatic cancer cells in vitro and in vivo, and increases chemosensitivity to 5-fluorouracil and gemcitabine

Pancreatic cancer (PC) is a common malignancy with a poorly understood pathogenesis. Currently, the efficacy of anti-PC therapies is insufficient, partially due to the chemoresistance of cancer cells. The present study aimed to elucidate the role of miR-183 in the proliferation, apoptosis, and chemosensitivity to 5-fluorouracil and gemcitabine of human PC cells and the associated mechanisms. PANC-1 cells were transfected with microRNA (miR)-183 inhibitors, and the effect of miR-183 on cell proliferation was evaluated via MTT assay. Apoptosis and cell cycle distribution were determined by flow cytometry. In vivo tumor xenograft models of PANC-1 cells were generated in BALB/c nude mice to examine the effect of miR-183 downregulation on tumor growth. Furthermore, components of the phosphatase and tensin homolog deleted on chromosome ten (PTEN)/phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway were examined via reverse transcription-quantitative polymerase chain reaction and western blotting in the collected cells. Finally, PANC-1 cells were treated with 5-fluorouracil or gemcitabine and transfected with miR-183 inhibitors, and the viability of cells was determined by MTT assay. The results demonstrated that knockdown of miR-183 could significantly decrease proliferation and promote apoptosis of PANC-1 cells. The cells transfected with miR-183 inhibitors were significantly arrested at the G₁ phase (P<0.01). Furthermore, miR-183 downregulation led to significant decreases in the mRNA levels of PI3K, Akt and B cell lymphoma-2 (Bcl-2) expression (P<0.001), and significant increases in PTEN and Bcl-2 associated X protein expression in PANC-1 cells (P<0.001). Knockdown of miR-183 was able to significantly increase the chemosensitivity of PANC-1 cells to 5-fluorouracil and gemcitabine. These results indicate that downregulation of miR-183 can inhibit the growth of PC cells in vitro and in vivo, and increase cell sensitivity to 5-fluorouracil and gemcitabine through regulating the PTEN/PI3K/Akt signaling pathway.

SUN2: A potential therapeutic target in cancer

The incidence of cancer is increasing at an alarming rate despite recent advances in prevention strategies, diagnostics and therapeutics for various types of cancer. The identification of novel biomarkers to aid in prognosis and treatment for cancer is urgently required. Uncontrolled proliferation and dysregulated apoptosis are characteristics exhibited by cancer cells in the initiation of various types of cancer. Notably, aberrant expression of crucial oncogenes or cancer suppressors is a defining event in cancer occurrence. Research has demonstrated that SAD1/UNC84 domain protein-2 (SUN2) serves a suppressive role in breast cancer, atypical teratoid/rhabdoid tumors and lung cancer progression. Furthermore, SUN2 inhibits cancer cell proliferation, migration and promotes apoptosis. Recent reports have also shown that SUN2 serves prominent roles in resistance to the excessive DNA damage that destabilizes the genome and promotes cancer development, and these functions of SUN2 are critical for evading initiation of cancer. Additionally, increasing evidence has demonstrated that SUN2 is involved in maintaining cell nuclear structure and appears to be a central component for organizing the natural nuclear architecture in cancer cells. The focus of the present review is to provide an overview on the pharmacological functions of SUN2 in cancers. These findings suggest that SUN2 may serve as a promising therapeutic target and novel predictive marker in various types of cancer.

Upregulated miR-221/222 promotes cell proliferation and invasion and is associated with invasive features in retinoblastoma

BACKGROUND AND OBJECTIVES

MicroRNA (miR-221/222) is frequently overexpressed in many cancers and is associated with poor prognosis. However, the role of miR-221/222 in retinoblastoma (RB) remains unclear. This study aimed to detect the clinical significance of miR-221/222 in RB patients and explore its role in RB cells in vitro.

METHODS

Expression of miR-221/222 was assessed in fresh RB tissue collected from 64 eyes and normal retinal tissues from 18 unrelated donor cadaver eyes by quantitative real time RT-PCR analysis (qRT-PCR), and correlated with the histopathological findings. Human RB Y79 cells were transfected with miR-221/222 precursors or inhibitors to overexpress or downregulate miR-221/222 expression, respectively, using Lipofectamine 2000 reagent. The biological effects of miR-221/222 were then assessed by cell viability assays, colony formation assays, apoptosis detection assays, Matrigel® invasion assays, and wound-healing assays.

RESULTS

Higher miR-221/222 expression was detected in RB tissues compared to that of the normal retinal tissues (p< 0.001). Higher miR-221/222 expression was correlated with invasion in patients with RB. Targeting of miR-221/222 induced apoptosis and inhibited Y79 cell proliferation, migration, and invasion in vitro. However, overexpression of miR-221/222 promoted Y79 cell proliferation, migration, and invasion in vitro.

CONCLUSIONS

Overexpression of miR-221/222 was associated with tumor invasiveness in patients with RB. The miR-221/222 cluster might be used as a potential therapeutic strategy in clinical practice.

Differential expression profiles of microRNAs in highly and weakly invasive/metastatic pancreatic cancer cells

Pancreatic cancer is the eighth-leading cause of cancer-associated mortality worldwide. To date, the cellular and molecular mechanisms associated with the invasion and metastasis of pancreatic cancer remain unclear. To examine these mechanisms, a microRNA (miRNA/miR) microarray with 1,965 genes was hybridized with labeled miRNA probes from invasive PC-1.0 and non-invasive PC-1 cells for molecular profiling analysis. In addition, reverse transcription quantitative-polymerase chain reaction (RT-qPCR) was utilized to validate the microarray results. Online miRNA target prediction algorithms online were used to predict the target genes of the differentially expressed miRNAs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) term enrichment analysis were performed for the potential targets of the differentially expressed miRNAs. The results demonstrated that 54 miRNAs were differentially expressed, of which 33 were upregulated and 21 were downregulated in the PC-1.0 cell line compared with the PC-1 cell line. A total of 6 upregulated miRNAs (miR-31, -34a, -181a, -181b, -193a-3p, and -193b) and 4 downregulated miRNAs (miR-221, -222, -484, and -502-3p) were selected from these 54 miRNAs and validated by RT-qPCR. The differentially expressed miRNAs were further validated by RT-qPCR in the human pancreatic cancer cell lines AsPC-1 (highly invasive) and CAPAN-2 (less invasive). The results revealed that 2 upregulated miRNAs (miR-34a and -193a-3p) and 4 downregulated miRNAs (miR-221, -222, -484, and -502-3p) exhibited a consistent expression pattern between the PC-1.0/PC-1 and AsPC-1/CAPAN-2 pancreatic cancer cells. The GO and KEGG enrichment analysis indicated that the mRNAs potentially targeted by miRNAs were involved in a range of biological functions. These results suggest that different miRNA expression profiles occur between highly and weakly invasive and metastatic pancreatic cancer cell lines, and may affect a variety of biological functions in pancreatic cancer.

MicroRNA analysis of gastroenteropancreatic neuroendocrine tumors and metastases

The incidence of neuroendocrine neoplasias (NEN) continues to increase. Since the primary tumor cannot be diagnosed in some cases of metastatic disease, new biomarkers are clearly needed to find the most probable site of origin. Tissue samples from 79 patients were analyzed and microRNA profiles were generated from a total of 76 primary tumors, 31 lymph node and 14 solid organ metastases. NEN metastases were associated with elevated levels of miR-30a-5p, miR-210, miR-339-3p, miR-345 and miR-660. Three microRNAs showed a strong correlation between proliferation index and metastatic disease in general (miR-150, miR-21 and miR-660). Further, each anatomic location (primary or metastatic) had one or more site-specific microRNAs more highly expressed in these tissues. Comparison between primary tumors and metastases revealed an overlap only in pancreatic (miR-127) and ileal tumors (let-7g, miR-200a and miR-331). This thorough analysis of gastroenteropancreatic neuroendocrine tumors demonstrates site-specific microRNA profiles, correlation with proliferation indices as well as corresponding nodal and distant metastases. Using microRNA profiling might improve NEN diagnostics by linking metastases to a most probable site of origin.

Exosome-mediated miR-222 transferring: An insight into NF-κB-mediated breast cancer metastasis

The subtypes of distant-organ metastasis led to treatment failure and poor prognosis are major obstacles in the management of patients with advanced breast cancer (BCa). Emerging evidences demonstrated that exosomes act as mediators for intercellular communication between various types of cells in the local tumor microenvironment. The present study aims to investigate whether BCa-derived exosomes are capable of cell-cell transferring miR-222 for BCa metastatic progression. Results showed that exosomal miR-222 is highly expressed in BCa patients with lymphatic metastasis. Consistently, the elevated levels of exosomal miR-222 are closely correlated with the high aggressivity of BCa cell lines. miR-222 promoting the aggressivity of BCa cells was confirmed in vitro and in vivo. Mechanistically, miR-222 directly targets PDLIM2, a tumor suppressor gene, leading to activation of NF-κB signal pathway. In conclusion, the levels of exosomal miR-222 are correlated with BCa metastatic progression. Exosome-transferred miR-222 promotes migration and invasion of BCa cells. miR-222 contributes to tumorigenicity of BCa cells through down-regulation of PDLIM2 and consequently activating NF-κB.

Hierarchical structural component modeling of microRNA-mRNA integration analysis

BACKGROUND

Identification of multi-markers is one of the most challenging issues in personalized medicine era. Nowadays, many different types of omics data are generated from the same subject. Although many methods endeavor to identify candidate markers, for each type of omics data, few or none can facilitate such identification.

RESULTS

It is well known that microRNAs affect phenotypes only indirectly, through regulating mRNA expression and/or protein translation. Toward addressing this issue, we suggest a hierarchical structured component analysis of microRNA-mRNA integration ("HisCoM-mimi") model that accounts for this biological relationship, to efficiently study and identify such integrated markers. In simulation studies, HisCoM-mimi showed the better performance than the other three methods. Also, in real data analysis, HisCoM-mimi successfully identified more gives more informative miRNA-mRNA integration sets relationships for pancreatic ductal adenocarcinoma (PDAC) diagnosis, compared to the other methods.

CONCLUSION

As exemplified by an application to pancreatic cancer data, our proposed model effectively identified integrated miRNA/target mRNA pairs as markers for early diagnosis, providing a much broader biological interpretation.

MicroRNA-222-3p/GNAI2/AKT axis inhibits epithelial ovarian cancer cell growth and associates with good overall survival

Ovarian carcinoma is the most lethal gynecologic tumor worldwide. Despite having developed molecular diagnostic tools and targeted therapies over the past few decades, patient survival is still quite poor. Numerous studies suggest that microRNAs are key regulators of many fundamental biological processes, including neoplasia and tumor progression. miR-222 is one of those miRNAs that has attracted much attention for its multiple roles in human diseases, especially cancer. The potential role of microRNAs in ovarian cancer has attracted much attention in recent years. Some of these microRNAs have been suggested as potential therapeutic targets for EOC patients. In this study, we sought to investigate the biologic functions of miR-222-3p in EOC carcinogenesis. Herein, we examined the expression of miR-222-3p in EOC patients, mouse models and cell lines, and found that higher expression of miR-222-3p was associated with better overall survival in EOC patients, and its level was negatively correlated with tumor growth in vivo. Furthermore, in-vitro experiments indicated that miR-222-3p inhibited EOC cell proliferation and migration, and decreased the phosphorylation of AKT. We identified GNAI2 as a target of miR-222-3p. We also found that GNAI2 promoted EOC cell proliferation, and is an activator of the PI3K/AKT pathway. We describe the characterization of a novel regulatory axis in ovarian cancer cells, miR-222-3p/GNAI2/AKT and its potential application as a therapeutic target for EOC patients.

IL-24 modulates the high mobility group (HMG) A1/miR222 /AKT signaling in lung cancer cells

Interleukin (IL)-24, a novel tumor suppressor/cytokine exhibits antitumor activity against a broad-spectrum of human cancer cells. In a recent study, we showed that IL-24 inhibited AKT in lung cancer cells. However, the molecular mechanism of AKT inhibition by IL-24 remains elusive.The high mobility group (HMG) A1 a member of the non-histone chromosomal proteins and commonly referred to as architectural transcription factor, regulates transcription of various genes involved in cell growth and survival. Overexpression of HMGA1 has been shown to be associated with tumor progression and metastasis in several cancers, including human lung cancer. A recent study demonstrated that HMGA1 activates AKT function by reducing the activity of the protein phosphatase, phosphatase 2A subunit B (PPP2R2A) via the oncogenic micro (mi) RNA-222. Based on this report we hypothesized that IL-24-mediated AKT inhibition involved the HMGA1/miR-222 axis.To test our hypothesis, in the present study we used a H1299 lung cancer cell line that expressed exogenous human IL-24 when induced with doxycycline (DOX). Induction of IL-24 expression in the tumor cells markedly reduced HMGA1 mRNA and protein levels. Using a mechanistic approach, we found that IL-24 reduced miR-222-3p and -5p levels, as determined by qRT-PCR. Associated with HMGA1 and miR-222 inhibition was a marked increase in PPP2R2A, with a concomitant decrease in phosphorylated AKTT308/S473 expression. SiRNA-mediated knockdown of HMGA1 in combination with IL-24 significantly reduced AKT T308/S473 protein expression and greatly reduced cell migration and invasion compared with individual treatments. Further combination of IL-24 and a miR-222-3p inhibitor significantly increased PPP2R2A expression.Our results demonstrate for the first time that IL-24 inhibits AKT via regulating the HMGA1/miR-222 signaling node in human lung cancer cells and acts as an effective tumor suppressor. Thus, a therapy combining IL-24 with HMGA1 siRNA or miR-222-3p inhibitor should present effective treatment of lung cancer.

The role of miRNAs in the diagnosis, chemoresistance, and prognosis of pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) remains a very challenging malignancy with late presentation, metastatic potential, chemoresistance, and poor prognosis. Therefore, there is an urgent need for novel diagnostic and prognostic biomarkers. miRNAs are small noncoding RNAs that regulate the expression of multitude number of genes. Aberrant expression of miRNAs has been linked to the development of various malignancies, including PDAC. A series of miRNAs have been defined as holding promise for early diagnostics, as indicators of therapy resistance, and even as markers for prognosis in PDAC patients. In this review, we summarize the current knowledge on the role of miRNAs in diagnosis, chemoresistance, and prognosis in PDAC patients.

miR-221/222 cluster expression improves clinical stratification of non-muscle invasive bladder cancer (TaT1) patients' risk for short-term relapse and progression

Clinical heterogeneity of bladder cancer prognosis requires the identification of bladder tumors' molecular profile to improve the prediction value of the established and clinically used markers. In this study, we have analyzed miR-221/222 cluster expression in bladder tumors and its clinical significance for patients' prognosis and disease outcome. The study included 387 tissue specimens. Following extraction, total RNA was polyadenylated at 3'-end and reversed transcribed. SYBR-Green based qPCR assays were performed for the quantification of miR-221/222 expression. Extensive statistical analysis was completed for the evaluation of miR-221/222 cluster's clinical significance. The expression of miR-221/222 is significantly downregulated in tumors compared to normal urothelium, while ROC curve and logistic regression analysis highlighted cluster's discriminatory ability. However, miR-222 levels were increased in muscle-invasive (T2-T4) compared to superficial tumors (TaT1), and in high compared to low-grade tumors. Kaplan-Meier survival curves and Cox regression analysis revealed the stronger risk of TaT1 patients overexpressing miR-222 for disease short-term relapse and progression following treatment. Moreover, multivariate Cox models highlighted the independent prognostic value of miR-222 overexpression for TaT1 patients' poor prognosis. Finally, the analysis of miR-222 expression improved significantly the positive prediction strength of the clinically used prognostic markers of tumor stage, grade, EORTC risk-stratification and recurrence at the first follow-up cystoscopy for TaT1 patients' outcome, and resulted to higher clinical net benefit following decision curve analysis. In conclusion, the expression of miR-221/222 cluster is deregulated in bladder tumors and miR-222 overexpression results to a superior positive prediction of TaT1 patients' short-term relapse and progression.

Prognostic value of microRNA expression levels in pancreatic adenocarcinoma: a review of the literature

Background

Clinical and pathologic markers of prognosis and patterns of failure help guide clinicians in selecting patients for adjuvant therapy after surgical resection for pancreatic adenocarcinoma (PDAC). Recent studies have reported the prognostic utility of microRNA profiling in numerous malignancies. Here, we review and summarize the current literature regarding associations between microRNA expression and overall survival in PDAC patients.

Materials and Methods

We conducted a systematic search in the PubMed database to identify all primary research studies reporting prognostic associations between tumor and/or serum microRNA expression and overall survival in PDAC patients. Eligible articles were reviewed by the authors and relevant findings are summarized below.

Results

We found 53 publications that fit our search criteria. In total, 23 up-regulated and 49 down-regulated miRNAs have been associated with worse overall survival. MiR-21 is the most commonly reported miRNA, appearing in 19 publications, all of which report aberrant over-expression and association with shorter survival in PDAC. Other miRNAs that appear in multiple publications include miR-10b, −21, −34a, −155, −196a, −198, −200c, −203, −210, −218, −222, and −328. We summarize the preclinical and clinical data implicating these miRNAs in various molecular signaling pathways and cellular functions.

Conclusions

There is growing evidence that miRNA expression profiles have the potential to provide tumor-specific prognostic information to assist clinicians in more appropriately selecting patients for adjuvant therapy. These molecules are often aberrantly expressed and exhibit oncogenic and/or tumor suppressor functions in PDAC. Additional efforts to develop prognostic and predictive molecular signatures, and further elucidate miRNA mechanisms of action, are warranted.

MicroRNAs with prognostic significance in bladder cancer: a systematic review and meta-analysis

The aim of this study was to systematically review articles that investigated the prognostic significance of different microRNAs in bladder cancer (BC). We systematically searched PubMed, Web of Science, and Embase to identify relevant studies until March 2016. After screening, 26 studies that involved 2753 patients were included. Results suggested that many miRs expression aberration may predict prognosis in patients with BC. There are six miRs (miR-21, miR-143, miR-155, miR-200, miR-214, and miR-222) were reported by at least two studies, and we performed meta-analysis in the corresponding studies. Accordingly, we found that high miR-21 expression was associated with poor overall survival [OS; hazard ratio (HR) = 3.94, 95% CI 2.08–7.44]. High miR-143 expression was associated with poor progression-free survival (PFS; HR = 3.78, 95% CI 1.61–8.89). High miR-155 expression was associated with poor PFS (HR = 8.10, 95% CI 2.92–22.48). High miR-222 expression was associated with poor OS (HR = 3.39, 95% CI 1.10–10.41). Meanwhile, low miR-214 expression was correlated with poor RFS(HR = 0.34, 95% CI 0.22–0.53). Our comprehensive systematic review concluded that microRNAs, particularly miR-21, miR-143, miR-155, miR-214, and miR-222, could serve as meticulous follow-up markers for early detection of progression or recurrence and even useful therapeutic targets for the treatment in patients with BC.

MicroRNA-222 Expression as a Predictive Marker for Tumor Progression in Hormone Receptor-Positive Breast Cancer

Purpose

The microRNA-221/222 (miR-221/222) gene cluster has been reported to be associated with the promotion of epithelial-mesenchymal transition (EMT), downregulation of estrogen receptor-α, and tamoxifen resistance in breast cancer. We studied the expression of miR-222 in human breast cancer samples to analyze its relationship with clinicopathologic features of the tumor, including estrogen receptor status, expression of EMT markers, and clinical outcomes.

Methods

Quantitative real-time polymerase chain reaction was performed to detect the expression of miR-222 in 197 invasive breast cancers. Expression of EMT markers (vimentin, smooth muscle actin, osteonectin, N-cadherin, and E-cadherin) was evaluated using immunohistochemistry.

Results

High miR-222 levels were associated with high T stage, high histologic grade, high Ki-67 proliferation index, and HER2 gene amplification. Its expression was significantly higher in the luminal B and human epidermal growth factor receptor 2-positive (HER2+) subtypes than in the luminal A and triple-negative subtypes. In the hormone receptor-positive subgroup, there was a significant negative correlation between miR-222 and estrogen receptor expression, and miR-222 expression was associated with EMT marker expression. In the group as a whole, high miR-222 expression was not associated with clinical outcome. However, subgroup analyses by hormone receptor status revealed that high miR-222 expression was a poor prognostic factor in the hormone receptor-positive subgroup, but not in the hormone receptor-negative subgroup.

Conclusion

This study showed that miR-222 is associated with down-regulation of the estrogen receptor, EMT, and tumor progression in hormone receptor-positive breast cancer, indicating that miR-222 might be associated with endocrine therapy resistance and poor clinical outcome in hormone receptor-positive breast cancer.

Potential Value of miR-221/222 as Diagnostic, Prognostic, and Therapeutic Biomarkers for Diseases

microRNAs (miRNAs) are short non-coding RNAs that regulate gene expression by base pairing with their target messenger RNAs. Dysregulation of miRNAs is involved in the pathological initiation and progression of many human diseases. miR-221 and miR-222 (miR-221/222) are two highly homologous miRNAs, and they are significantly overexpressed in several types of human diseases. Silencing miR-221/222 could represent a promising approach for therapeutic studies. In the present review, we will describe the potential value of miR-221/222 as diagnostic, prognostic, and therapeutic biomarkers in various diseases including cancer and inflammatory diseases.

Systematic review of peri-operative prognostic biomarkers in pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) continues to be associated with a poor prognosis. This systematic review aimed to summarize the literature regarding potential prognostic biomarkers to facilitate validation studies and clinical application.

METHODS

A systematic review was performed (2004-2014) according to PRISMA guidelines. Studies were ranked using REMARK criteria and the following outcomes were examined: overall/disease free survival, nodal involvement, tumour characteristics, metastasis, recurrence and resectability.

RESULTS

256 biomarkers were identified in 158 studies. 171 biomarkers were assessed with respect to overall survival: urokinase-type plasminogen activator receptor, atypical protein kinase C and HSP27 ranked the highest. 33 biomarkers were assessed for disease free survival: CD24 and S100A4 were the highest ranking. 17 biomarkers were identified for lymph node involvement: Smad4/Dpc4 and FOXC1 ranked highest. 13 biomarkers were examined for tumour grade: mesothelin and EGFR were the highest ranking biomarkers. 10 biomarkers were identified for metastasis: p16 and sCD40L were the highest ranking. 4 biomarkers were assessed resectability: sCD40L, s100a2, Ca 19-9, CEA.

CONCLUSION

This review has identified and ranked specific biomarkers that should be a primary focus of ongoing validation and clinical translational work in PDAC.

miR-221/222 induces pancreatic cancer progression through the regulation of matrix metalloproteinases

MicroRNAs are involved in the initiation and progression of pancreatic cancer. In this study, we showed that miR-221/222 is overexpressed in pancreatic cancer. MiR-221/222 overexpression significantly promoted pancreatic cancer cell proliferation and invasion while inhibiting apoptosis. The expression of the matrix metalloproteinases (MMPs) MMP-2 and MMP-9 was increased in miR-221/222 mimic-transfected pancreatic cancer cells. Validation experiments identified TIMP-2 as a direct target of miR-221/222. These data indicate that overexpressed miR-221/222 may play an oncogenic role in pancreatic cancer by inducing the expression of MMP-2 and MMP-9, thus leading to cancer cell invasion.

Prognostic value of Ki-67 in solid pseudopapillary tumor of the pancreas: Huashan experience and systematic review of the literature

BACKGROUND

Solid pseudopapillary tumor of the pancreas (SPTP) is considered to have a low Ki-67 proliferation index, which may explain the generally good clinical outcome. The aim of our study was to evaluate whether Ki-67 has prognostic value in SPTP.

METHODS

A case series study of patients with SPTP treated in our institution from June 2002 to April 2014 was conducted. Prognostic factors for clinical outcomes were analyzed by the use of clinical decision and survival analysis. In addition, we performed a systematic review and pooled analysis to evaluate our results.

RESULTS

The institutional data included 71 patients (13 male and 58 female) ranging in age from 12 to 64 years (median, 31 years). Three patients developed local recurrence and/or liver metastasis after initial surgery. The 5-year recurrence-free survival rate was 93.6%. One patient died of disease, with the 5-year disease-specific survival rate of 98.5%. Ki-67 index ≥ 4% was found significantly associated with the survival of SPTP. Twenty-six studies comprising 163 patients were included in the pooled analysis based on our inclusion criteria. A total of 15 cases showed a Ki-67 index ≥ 4%. Kaplan-Meier survival analysis confirmed that Ki-67 index ≥ 4% was significantly associated with poorer recurrence-free survival and disease-specific survival (both P < .001).

CONCLUSION

This study highlighted a potential role of Ki-67 in predicting adverse outcome of patients with SPTP and should be considered as part of routine histological reporting of SPTP.

The Significance of miR-34a Expression in Endometrial Carcinogenesis: Correlation With Expression of p16 and Ki-67 Proteins in Endometrial Cancers

Background:

A microRNA, miR-34a, plays a key role in inhibiting cellular transformation and carcinogenesis by controlling cell cycle regulation and cell proliferation in various human tumors. However, miR-34a has rarely been reported in endometrial cancer research in Korea. This study was undertaken to analyze miR-34a expression in simple endometrial hyperplasia and endometrial cancer, and to evaluate the relationship between expression of miR-34a and p16 and Ki-67 proteins in endometrial cancers.

Methods:

A retrospective study was carried out on 66 formalin-fixed, paraffin-embedded tissues with simple endometrial hyperplasia (31 cases) and endometrial cancer (35 cases) patients. These were analyzed for miR-34a expression by quantitative real-time PCR, and the expression of p16 and Ki-67 proteins in endometrial cancers was evaluated by immunohistochemistry.

Results:

The miR-34a expression level was lower in endometrial cancer tissues (−0.71 ± 3.90) than in simple endometrial hyperplasia tissues (2.68 ± 8.62). The endometrial hyperplasia tissues showed underexpression of miR-34a in 13 of the 31 cases (41.9%) while the endometrial cancer tissues showed underexpression of miR-34a in 24 of 35 cases (68.6%). Thus, miR-34a was significantly underexpressed in endometrial cancer tissues when compared endometrial hyperplasia tissues (P = 0.046). Overexpression of p16 was detected in 25 (71.4%) and Ki-67 immunoreactivity was detected in 27 (77.1%) of the 35 endometrial cancers. Although not statistically significant, the frequency of p16 and Ki-67 overexpression tended to be lower in the cases with miR-34a underexpression than in cases with miR-34a overexpression.

Conclusions:

These findings suggest that underexpression of miR-34a might be involved in endometrial carcinogenesis. Further studies are needed to define the relationship between miR-34a expression and tissue specific protein expression.

MicroRNA-222 Controls Human Pancreatic Cancer Cell Line Capan-2 Proliferation by P57 Targeting

Pancreatic cancer (PC) is one of the most common cancers and has a poor prognosis due to late diagnosis and ineffective therapeutic multimodality. MicroRNAs (miRNAs, miRs) are a group of non-coding, small RNAs with active biological activities. In our investigation, human pancreatic cancer cell line Capan-2 were transfected with miR-222 mimics, inhibitors or their negative controls. Cell proliferation was assessed by Cell Counting Kit-8 (CCK-8), EdU incorporation assay and cell cycle determination by flow cytometry. MiR-222 and putative target gene expression levels including p27, p57 and PTEN were determined using quantitative reverse transcription polymerase chain reactions and Western blotting. Our results showed that miR-222 could lead to increased vitality and proliferative rate of Capan-2 cells, and also higher S-phase and lower G1-phase of cell cycle. Further, we found p57 at protein level, but not p27 nor PTEN, was regulated by miR-222 in Capan-2 cells. Finally, we co-transfected miR-222 inhibitor and p57 si-RNA into Capan-2 cells, and found that proliferation-suppressing effects of miR-222 inhibitor on Capan-2 cells could be partially reversed by silencing p57. Our results indicate that miR-222 controls Capan-2 cell proliferation by targeting p57. This study provides a novel idea for developing effective therapeutic strategy for PC patients through inhibiting miR-222.

Triptolide Inhibits Lung Cancer Cell Migration, Invasion, and Metastasis

BACKGROUND

Triptolide is an extract from Tripterygium wilfordii used in traditional Chinese medicine to treat autoimmune disorders. Triptolide has anticancer effects in vitro and is reported to impair cancer cell migration. We studied whether triptolide inhibits lung cancer cell migration and metastasis.

METHODS

We determined the microRNA expression profile of triptolide-treated cells. We tested the effects of triptolide treatment on migration and invasion of lung cancer cells by using Transwell filters coated with fibronectin and Matrigel, respectively. Western blot analyses were used to compare expression of proteins involved in cell migration before and after 10 nmol/L triptolide treatment. Tail vein injections with H358 cells were performed. The mice were treated with 1 mg/kg triptolide or vehicle by intraperitoneal injection three times per week. Lung and liver metastases were compared at 9 weeks. Means of groups were compared by using a t test.

RESULTS

Triptolide altered the expression of microRNAs involved in cellular movement and significantly decreased migration and invasion of lung cancer cells from approximately 18 to 3 cells per field (p < 0.001). Triptolide decreases focal adhesion kinase expression, which leads to impairment of downstream signaling. Finally, triptolide-treated mice injected with lung cancer cells significantly decreased metastatic colony formation in the lungs (p < 0.01).

CONCLUSIONS

Triptolide decreases lung cancer cell migration and invasion in vitro and inhibits metastatic tumor formation in mice. Triptolide suppresses focal adhesion kinase, which causes deregulation of the migration machinery. These results suggest that triptolide inhibits lung cancer metastasis and should be investigated as a new lung cancer therapy.

Programmed cell death 6 interacting protein (PDCD6IP) and Rabenosyn-5 (ZFYVE20) are potential urinary biomarkers for upper gastrointestinal cancer

PURPOSE

Cancer of the upper digestive tract (uGI) is a major contributor to cancer-related death worldwide. Due to a rise in occurrence, together with poor survival rates and a lack of diagnostic or prognostic clinical assays, there is a clear need to establish molecular biomarkers.

EXPERIMENTAL DESIGN

Initial assessment was performed on urine samples from 60 control and 60 uGI cancer patients using MS to establish a peak pattern or fingerprint model, which was validated by a further set of 59 samples.

RESULTS

We detected 86 cluster peaks by MS above frequency and detection thresholds. Statistical testing and model building resulted in a peak profiling model of five relevant peaks with 88% overall sensitivity and 91% specificity, and overall correctness of 90%. High-resolution MS of 40 samples in the 2-10 kDa range resulted in 646 identified proteins, and pattern matching identified four of the five model peaks within significant parameters, namely programmed cell death 6 interacting protein (PDCD6IP/Alix/AIP1), Rabenosyn-5 (ZFYVE20), protein S100A8, and protein S100A9, of which the first two were validated by Western blotting.

CONCLUSIONS AND CLINICAL RELEVANCE

We demonstrate that MS analysis of human urine can identify lead biomarker candidates in uGI cancers, which makes this technique potentially useful in defining and consolidating biomarker patterns for uGI cancer screening.

Circulating miR-222 in plasma and its potential diagnostic and prognostic value in gastric cancer

Previous studies have revealed the significance of circulating microRNAs as biomarkers for cancers. The aim of this study was to detect the levels of circulating microRNA-222 (miR-222) in plasma of gastric cancer (GC) patients and evaluate its diagnostic and prognostic value. Levels of circulating miR-222 were detected by using qRT-PCR in plasma of 114 GC patients, 36 chronic atrophic gastritis (CAG) patients and 56 healthy controls. The result showed that the expression of circulating miR-222 in plasma was significantly upregulated in GC compared with CAG and healthy controls (all at P < 0.001). And its high level was significantly correlated with clinical stages (P < 0.001) and lymph nodes metastasis (P = 0.009). The receiver operating characteristics (ROC) curve analyses revealed that miR-222 had considerable diagnostic accuracy, yielded an AUC (the areas under the ROC curve) of 0.850 with 66.1 % sensitivity and 88.3 % specificity in discriminating GC from healthy controls. Moreover, Kaplan-Meier analysis demonstrated a correlation between increased circulating miR-222 level and reduced disease-free survival (P = 0.016) and overall survival (P = 0.012). In multivariate analysis stratified for known prognostic variables, circulating miR-222 was identified as an independent prognostic marker. In conclusion, our findings suggested that circulating miR-222 in plasma might be a potential and useful noninvasive biomarker for the early detection and prognosis of GC.

Increased expression of miR-222 is associated with poor prognosis in bladder cancer

BACKGROUND

MicroRNA-222 (miR-222) has been shown to play a potential oncogenic role in bladder cancer. The aim of this study was to evaluate the expression of miR-222 in bladder cancer and its potential relevance to clinicopathological characteristics and patient survival.

METHODS

Surgical specimens of cancer tissue and adjacent normal tissue were obtained from 97 patients with bladder cancer. The relative expression levels of miR-222 in the cancer and the normal adjacent tissue were measured by quantitative reverse-transcriptase PCR. We analyzed their correlation with clinicopathological parameters and prognostic value.

RESULTS

The expression level of miR-222 was significantly higher in tumor tissues than in corresponding non-cancerous tissues (5.46 ± 1.45 versus 1.92 ± 0.65, P <  0.0001), and a high expression of miR-222 was found to be significantly associated with tumor grade (P = 0.003) and tumor stage (P = 0.005). The miR-222 expression level was classified as high or low in relation to the median value (cutoff value = 5.15). Kaplan-Meier analysis showed that patients with higher levels of miR-222 had significantly poorer survival than those with lower expression of this miRNA in patients, with a 5-year overall survival of 29.53% and 52.75%, respectively (P = 0.0034). In the multivariate Cox proportional hazards analysis, which included miR-222 level, tumor grade, tumor stage, and tumor number, high miR-222 expression was independently associated with poor survival (P < 0.001; hazard ratio 6.17; 95% CI 2.33 to 10.39).

CONCLUSION

miR-222 overexpression is involved in the poor prognosis of bladder cancer and can be used as a biomarker for selection of cases requiring special attention.

URG11 predicts poor prognosis of pancreatic cancer by enhancing epithelial-mesenchymal transition-driven invasion

The poor prognosis and high recurrent rate of pancreatic cancer (PC) necessitates the discovery of new predictive markers of PC invasion and prognosis. In this study, we evaluated the expression pattern of up-regulated gene 11 (URG11) in a tissue microarray with 18 pairs of PC and adjacent normal tissues. It was shown that URG11 was significantly up-regulated in PC tissues. High expression levels of URG11 were detected in all PC specimens, but were rarely detected in adjacent non-tumorous tissues. In addition, high expression of URG11 was correlated to poor prognosis. Furthermore, it was discovered that URG11 was correlated to epithelial-mesenchymal transition (EMT) markers and clinical pathological parameters indicative of high PC invasion, while knockdown of URG11 significantly changed the expression pattern of EMT markers and decreased the invasion of PC cells. These findings indicate that URG11 might enhance the invasion of PC by inducing EMT and thus lead to poor PC prognosis. Thus, URG11 has the potential to be a new predictive biomarker of PC invasion and prognosis, which may help in the diagnosis and treatment of PC patients.

Aberrant MicroRNAs in Pancreatic Cancer: Researches and Clinical Implications

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with a high rate of mortality and poor prognosis. Numerous studies have proved that microRNA (miRNA) may play a vital role in a wide range of malignancies, including PDAC, and dysregulated miRNAs, including circulating miRNAs, are associated with PDAC proliferation, invasion, chemosensitivity, and radiosensitivity, as well as prognosis. Greater understanding of the roles of miRNAs in PDAC could provide insights into this disease and identify potential diagnostic markers and therapeutic targets. The current review focuses on recent advances with respect to the roles of miRNAs in PDAC and their practical value.

MicroRNA-222 expression and its prognostic potential in non-small cell lung cancer

Overexpression of miR-222 has been found in several types of cancers; however, the expression of miR-222 in non-small cell lung cancer (NSCLC) and its prognostic values are unclear. This study aimed to investigate whether the miR-222 expression level is related to clinicopathological factors and prognosis of NSCLC. Through a prospective study, 100 pairs of NSCLC tissues and adjacent normal tissues were examined by quantitative reverse-transcription polymerase chain reaction. The correlation between miR-222 expression and clinicopathological features was analyzed, and the significance of miR-222 as a prognostic factor and its relationship with survival were determined. Results showed that the expression levels of miR-222 were significantly elevated in the NSCLC tissue compared with that in adjacent normal tissue. In addition, Cox's proportional hazards model analysis confirmed that miR-222 high expression level was an independent predictor of poor prognosis. In conclusion, miR-222 overexpression is involved in the poor prognosis of NSCLC and can be used as a biomarker for selection of cases requiring especial attention.

Prognostic nomogram for nonresectable pancreatic cancer treated with gemcitabine-based chemotherapy

Background:

A nomogram is progressively being used as a useful predictive tool for cancer prognosis. A nomogram to predict survival in nonresectable pancreatic cancer treated with chemotherapy has not been reported.

Methods:

Using prospectively collected data on patients with nonresectable pancreatic cancer receiving gemcitabine-based chemotherapy at five Japanese hospitals, we derived a predictive nomogram and internally validated it using a concordance index and calibration plots.

Results:

In total, 531 patients were included between June 2001 and February 2013. The American Joint Committee on Cancer (AJCC) TNM stages were III and IV in 204 and 327 patients, respectively. The median survival time of the total cohort was 11.3 months. A nomogram was generated to predict survival probabilities at 6, 12, and 18 months and median survival time, based on the following six variables: age; sex; performance status; tumour size; regional lymph node metastasis; and distant metastasis. The concordance index of the present nomogram was higher than that of the AJCC TNM staging system at 12 months (0.686 vs 0.612). The calibration plots demonstrated good fitness of the nomogram for survival prediction.

Conclusions:

The present nomogram can provide valuable information for tailored decision-making early after the diagnosis of nonresectable pancreatic cancer.