MicroRNA profiling in locally advanced esophageal cancer indicates a high potential of miR‐192 in prediction of multimodality therapy response

To identify possible predictive markers, our study aimed to characterize microRNA (miRNA) profiles of responder and nonresponder in the multimodality therapy of locally advanced esophageal cancer. Initially, a microarray‐based approach was performed including eight patients with esophageal cancer. Patients received neoadjuvant chemoradiation followed by surgical resection. Major histopathological response was defined if resected specimens contained less than 10% vital tumor cells (major/minor response: 4/4 patients). Intratumoral RNA was isolated from both, pretherapeutic tissue biopsies in addition to corresponding surgical specimens. The profile of 768 miRNAs was analyzed in 16 specimens (preneoadjuvant and postneoadjuvant therapy). Selected miRNAs were than analyzed on pretherapeutic and post‐therapeutic biopsies of 80 patients with esophageal cancer, who underwent multimodality therapy (major/minor response: 30/50 patients). Comprehensive miRNA profiling identified miRNAs in pretherapeutic biopsies that were significantly different between major/minor responders. Based on the microarray results, miR‐192, miR‐194 and miR‐622 were selected and the dysregulated miRNAs were studied on an extended series of esophageal cancer patients. The expression of miR‐192, miR‐194 and miR‐622 was significantly reduced after neoadjuvant therapy confirming the array profiling data. Importantly, the pretherapeutic intratumoral expression of miR‐192 and miR‐194 was significantly associated with the histopathologic response of esophageal squamous cell carcinoma to multimodal therapeutic treatment. Therefore, in patients with locally advanced esophageal cancer undergoing neoadjuvant chemoradiation followed by esophagectomy, miR‐192 and miR‐194 in pretherapeutic biopsies are considered as indicators of major histopathologic regression.     

Elevated expression of microRNAs 155, 203, 210 and 222 in pancreatic tumors is associated with poorer survival

Pancreatic cancer is the eighth most common cancer and has an overall 5‐year survival rate lower than 10%. Because of their ability to regulate gene expression, microRNAs can act as oncogenes or tumor‐suppressor genes and so have garnered interest as possible prognostic and therapeutic markers during the last decade. However, the prognostic value of microRNA expression in pancreatic cancer has not been thoroughly investigated. We measured the levels of miR‐155, miR‐203, miR‐210, miR‐216, miR‐217 and miR‐222 by quantitative RT‐PCR in a cohort of 56 microdissected pancreatic ductal adenocarcinomas (PDAC). These microRNAs were chosen as they had previously been shown to be differentially expressed in pancreatic tumors compared to normal tissues. The possible association of microRNA expression and patients' survival was examined using multivariate Cox's regression hazard analyses. Interestingly, significant correlations between elevated microRNA expression and overall survival were observed for miR‐155 (RR = 2.50; p = 0.005), miR‐203 (RR = 2.21; p = 0.017), miR‐210 (RR = 2.48; p = 0.005) and miR‐222 (RR = 2.05; p = 0.035). Furthermore, tumors from patients demonstrating elevated expression levels of all 4 microRNAs possessed a 6.2‐fold increased risk of tumor‐related death compared to patients whose tumors showed a lower expression of these microRNAs. This study provides the first evidence for an oncogenic activity of miR‐155, miR‐203, miR‐210 and miR‐222 in the development of pancreatic cancer as has been reported for other tumor types. Furthermore, the putative target genes for these microRNAs suggest a complex signaling network that can affect PDAC tumorigenesis and tumor progression.     

Diagnostic and prognostic implications of microRNA profiling in prostate carcinoma

This study aimed to investigate the microRNA (miRNA) profile in prostate carcinoma tissue by microarray analysis and RT‐qPCR, to clarify associations of miRNA expression with clinicopathologic data and to evaluate the potential of miRNAs as diagnostic and prognostic markers. Matched tumor and adjacent normal tissues were obtained from 76 radical prostatectomy specimens. Twenty‐four tissue pairs were analyzed using human miRNA microarrays for 470 human miRNAs. Differentially expressed miRNAs were validated by TaqMan RT‐qPCR using all 76 tissue pairs. The diagnostic potential of miRNAs was calculated by receiver operating characteristics analyses. The prognostic value was assessed in terms of biochemical recurrence using Kaplan–Meier and Cox regression analyses. Fifteen differentially expressed miRNAs were identified with concordant fold‐changes by microarray and RT‐qPCR analyses. Ten microRNAs (hsa‐miR‐16, hsa‐miR‐31, hsa‐miR‐125b, hsa‐miR‐145, hsa‐miR‐149, hsa‐miR‐181b, hsa‐miR‐184, hsa‐miR‐205, hsa‐miR‐221, hsa‐miR‐222) were downregulated and 5 miRNAs (hsa‐miR‐96, hsa‐miR‐182, hsa‐miR‐182*, hsa‐miR‐183, hsa‐375) were upregulated. Expression of 5 miRNAs correlated with Gleason score or pathological tumor stage. Already 2 microRNAs classified up to 84% of malignant and nonmalignant samples correctly. Expression of hsa‐miR‐96 was associated with cancer recurrence after radical prostatectomy and that prognostic information was confirmed by an independent tumor sample set from 79 patients. That was shown with hsa‐miR‐96 and the Gleason score as final variables in the Cox models build in the 2 patient sets investigated. Thus, differential miRNAs in prostate cancer are useful diagnostic and prognostic indicators. This study provides a solid basis for further functional analyses of miRNAs in prostate cancer.     

Plasma microRNAs are promising novel biomarkers for early detection of colorectal cancer

MicroRNA (miRNA) opens up a new field for molecular diagnosis of cancer. However, the role of circulating miRNAs in plasma/serum in cancer diagnosis is not clear. The aim of this study was to investigate whether plasma miRNAs can be used as biomarkers for the early detection of colorectal carcinoma (CRC). We measured the levels of 12 miRNAs (miR‐134, −146a, −17‐3p, −181d, −191, −221, −222, −223, −25, −29a, −320a and −92a) in plasma samples from patients with advanced colorectal neoplasia (carcinomas and advanced adenomas) and healthy controls using real‐time RT‐PCR. We found that plasma miR‐29a and miR‐92a have significant diagnostic value for advanced neoplasia. MiR‐29a yielded an AUC (the areas under the ROC curve) of 0.844 and miR‐92a yielded an AUC of 0.838 in discriminating CRC from controls. More importantly, these 2 miRNAs also could discriminate advanced adenomas from controls and yielded an AUC of 0.769 for miR‐29a and 0.749 for miR‐92a. Combined ROC analyses using these 2 miRNAs revealed an elevated AUC of 0.883 with 83.0% sensitivity and 84.7% specificity in discriminating CRC, and AUC of 0.773 with 73.0% sensitivity and 79.7% specificity in discriminating advanced adenomas. Collectively, these data suggest that plasma miR‐29a and miR‐92a have strong potential as novel noninvasive biomarkers for early detection of CRC.     

Expression of programmed cell death protein 1 (PD-1) and programmed cell death 1 ligand (PD-L1) in adenocarcinomas of the gastroesophageal junction change significantly after neoadjuvant treatment

BackgroundThe effects of cytotoxic chemotherapy on the expression of programmed cell death 1 (PD-1) and its ligand (PD-L1) in cancer cells and peritumoral cells are unclear. The aim of this study was to investigate the impact of neoadjuvant chemotherapy on PD-1 and PD-L1 expression in adenocarcinomas of the gastroesophageal junction.MethodsPD-1 and PD-L1 expression in cancer cells and tumor-infiltrating lymphocytes in paired diagnostic biopsies and surgical specimens from patients with pretreated and curatively resected adenocarcinomas of the gastroesophageal junction were evaluated by immunohistochemistry.ResultsPaired tumor samples were available from 40 patients. PD-1 expression in cancer cells (p < 0.001; Exact Symmetry Test) and tumor-infiltrating lymphocytes (p < 0.001; Exact Symmetry Test) increased significantly after neoadjuvant therapy. Furthermore, we observed a significant decrease in PD-L1 expression in cancer cells (p = 0.003) after neoadjuvant therapy was observed.ConclusionIn this study we could show that tumor-cell expression of PD-1 and PD-L1 was significantly altered in patients with adenocarcinomas of the gastroesophageal junction after receiving neoadjuvant chemotherapy. Based on these observations, patients might profit from the combined use of cytotoxic chemotherapy and the blockade of the PD-1 axis.     

Alterations of microRNAs and their targets are associated with acquired resistance of MCF‐7 breast cancer cells to cisplatin

Cancer cells that develop resistance to chemotherapeutic agents are a major clinical obstacle in the successful treatment of breast cancer. Acquired cancer chemoresistance is a multifactorial phenomenon, involving various mechanisms and processes. Recent studies suggest that chemoresistance may be linked to drug‐induced dysregulation of microRNA function. Furthermore, mounting evidence indicates the existence of similarities between drug‐resistant and metastatic cancer cells in terms of resistance to apoptosis and enhanced invasiveness. We studied the role of miRNA alterations in the acquisition of cisplatin‐resistant phenotype in MCF‐7 human breast adenocarcinoma cells. We identified a total of 103 miRNAs that were overexpressed or underexpressed (46 upregulated and 57 downregulated) in MCF‐7 cells resistant to cisplatin. These differentially expressed miRNAs are involved in the control of cell signaling, cell survival, DNA methylation and invasiveness. The most significantly dysregulated miRNAs were miR‐146a, miR‐10a, miR‐221/222, miR‐345, miR‐200b and miR‐200c. Furthermore, we demonstrated that miR‐345 and miR‐7 target the human multidrug resistance‐associated protein 1. These results suggest that dysregulated miRNA expression may underlie the abnormal functioning of critical cellular processes associated with the cisplatin‐resistant phenotype.     

Combined evaluation of a panel of protein and miRNA serum‐exosome biomarkers for pancreatic cancer diagnosis increases sensitivity and specificity

Late diagnosis contributes to pancreatic cancer (PaCa) dismal prognosis, urging for reliable, early detection. Serum‐exosome protein and/or miRNA markers might be suitable candidates, which we controlled for patients with PaCa. Protein markers were selected according to expression in exosomes of PaCa cell line culture supernatants, but not healthy donors' serum‐exosomes. miRNA was selected according to abundant recovery in microarrays of patients with PaCa, but not healthy donors' serum‐exosomes and exosome‐depleted serum. According to these preselections, serum‐exosomes were tested by flow cytometry for the PaCa‐initiating cell (PaCIC) markers CD44v6, Tspan8, EpCAM, MET and CD104. Serum‐exosomes and exosome‐depleted serum was tested for miR‐1246, miR‐4644, miR‐3976 and miR‐4306 recovery by qRT‐PCR. The majority (95%) of patients with PaCa (131) and patients with nonPa‐malignancies reacted with a panel of anti‐CD44v6, ‐Tspan8, ‐EpCAM and ‐CD104. Serum‐exosomes of healthy donors' and patients with nonmalignant diseases were not reactive. Recovery was tumor grading and staging independent including early stages. The selected miR‐1246, miR‐4644, miR‐3976 and miR‐4306 were significantly upregulated in 83% of PaCa serum‐exosomes, but rarely in control groups. These miRNA were also elevated in exosome‐depleted serum of patients with PaCa, but at a low level. Concomitant evaluation of PaCIC and miRNA serum‐exosome marker panels significantly improved sensitivity (1.00, CI: 0.95–1) with a specificity of 0.80 (CI: 0.67–0.90) for PaCa versus all others groups and of 0.93 (CI: 0.81–0.98) excluding nonPa‐malignancies. Thus, the concomitant evaluation of PaCIC and PaCa‐related miRNA marker panels awaits retrospective analyses of larger cohorts, as it should allow for a highly sensitive, minimally‐invasive PaCa diagnostics.     

TUBB3、TYMS mRNA 在进展期食管胃交界部腺癌组织中的表达及与新辅助化疗疗效的关系

目的：探讨β-微管蛋白Ⅲ（TUBB3）和胸苷酸合成酶（TYMS）mRNA 在进展期食管胃交界部腺癌（AEGJ）组织中的表达情况及在 XP 方案新辅助化疗疗效预测中的价值。方法54例进展期 AEGJ 患者均行 XP 方案化疗,并评价疗效。用分支 DNA -液相芯片技术检测 TUBB3、TYMS mRNA 的表达情况,分析各基因表达与化疗疗效的关系。结果54例患者新辅助化疗有效率为48.15％。TUBB3、TYMS mRNA 的低表达率分别18.52％％和25.93％;TUBB3、TYMS mRNA 的表达与化疗敏感性有关。结论 TUBB3、TYMS mRNA 低表达是 XP 方案新辅助化疗敏感性的影响因素,两者的表达情况可为 AEGJ 个体化新辅助化疗方案的选择提供有益的参考。     

Retracted: Glabridin attenuates the migratory and invasive capacity of breast cancer cells by activating microRNA‐200c

Current treatments for breast cancer, a common malignancy in human females, are less than satisfactory because of high rates of metastasis. Glabridin (GLA), which acts through the FAK/ROS signaling pathway, has been used as an antioxidant and anti‐metastatic agent. However, little is known regarding the effect of microRNA (miRNA) on GLA's anti‐metastatic activity. The miRNA‐200 family, which is frequently expressed at low levels in triple negative breast cancers, inhibits metastasis by blocking the epithelial–mesenchymal transition. Here, we found that GLA attenuated the migratory and invasive capacity of breast cancer cells by activating miR‐200c. GLA induced the mesenchymal–epithelial transition in vitro and in vivo, as determined by increased expression of the epithelial marker, E‐cadherin, and decreased expression of the mesenchymal marker, vimentin. Overexpression of miR‐200c enhanced the expression of E‐cadherin and decreased the expression of vimentin. Furthermore, in MDA‐MB‐231 and BT‐549 breast cancer cells exposed to GLA, knockdown of miR‐200c blocked the GLA‐induced mesenchymal–epithelial transition and alleviated the GLA‐induced inhibition of migration and invasion. Thus, elevation of miR‐200c by GLA has considerable therapeutic potential for anti‐metastatic therapy for breast cancer patients.     

Branched rolling circle amplification method for measuring serum circulating microRNA levels for early breast cancer detection

Serum circulating microRNAs (c‐miRNAs) are serving as useful biomarkers for cancer diagnosis. Here, we describe the development of a one‐step branched rolling circle amplification (BRCA) method to measure serum c‐miRNAs levels for early diagnosis of breast cancer. Four c‐miRNAs, c‐miRNA16 (c‐miR‐16), c‐miRNA21 (c‐miR‐21), c‐miRNA155 (c‐miR‐155), and c‐miRNA195 (c‐miR‐195) were isolated from the serum of 49 breast cancer patients (stages I‐IV) and 19 healthy controls, and analyzed using one‐step BRCA. The serum levels of c‐miR16, c‐miR21, c‐miR155, and c‐miR195 were higher (P < 0.0001) in stage I breast cancer patients than healthy controls. These levels were also higher in several breast cancer molecular subtypes (HER‐2 over‐expression, Luminal A, Luminal B, and triple negative breast cancer) than in healthy control subjects. The diagnostic accuracy of c‐miR16, c‐miR21, c‐miR155, and c‐miR195 for early diagnosis of breast cancer was confirmed by receiver operating characteristic (ROC) curve assay. These results show that the BRCA method can be used to measure serum c‐miRNAs levels, and that this method has high accuracy, sensitivity, and specificity. Moreover, both BRCA approach and quantitative real‐time PCR (qRT‐PCR) method show that the serum levels of c‐miR16, c‐miR21, c‐miR155, and c‐miR195 could be used as biomarkers to improve the early diagnosis of breast cancer, and distinguish different breast cancer molecular subtypes.     

Predicting response to neoadjuvant therapy in esophageal cancer

Despite improvements in preoperative staging, surgical techniques and postoperative care, the 5-year survival rate of patients with locally advanced esophageal cancer remains only approximately 15-40%. Therefore, multimodality treatment options have been widely promoted in the therapy of this malignant disease. However, recent meta-analyses evaluating randomized trials of neoadjuvant therapy protocols prior to surgery for patients with advanced esophageal cancer showed only modest improvement of survival for the whole treatment group. Among these patients, those with excellent histopathologic response seem to benefit greatly from neoadjuvant regimens. Therefore, predictive markers to allow individualization of multimodality therapy in locally advanced esophageal cancer are needed to identify those who will benefit the most. Unfortunately, there is still a great lack of markers for response assessment in patients with esophageal cancer undergoing multimodality therapy. Endoscopy, endoscopic biopsies, computed tomography and endoscopic ultrasound do not seem to provide reliable information for assessing the response to neoadjuvant therapy. Whether (18)F-fluorodeoxyglucose-PET can effectively characterize responders in neoadjuvant therapy protocols remains controversial. Finally, although results of mostly retrospective studies on molecular factors for response assessment in esophageal cancer patients are promising, these markers do not yet provide a reliable and cost-effective molecular tool for utilization in clinical practice.     

Esophagogastric junction adenocarcinoma: Preoperative chemoradiation or perioperative chemotherapy?

Multimodal treatment is currently the standard of care for locally advanced esophagogastric junction (EGJ) adenocarcinoma due to poor results after surgery alone. Neoadjuvant therapy is intended to shrink the tumor and eliminate potential circulating tumor cells. However, which neoadjuvant treatment is best for patients with EGJ tumors remains controversial. We aimed to compare outcomes of preoperative chemoradiation and perioperative chemotherapy for EGJ adenocarcinomas. For this purpose, we performed a thorough review of the literature describing neoadjuvant treatments for EGJ adenocarcinomas or comparing both therapies. Although some studies have shown better locoregional control and higher rates of complete pathologic response after chemoradiation, data suggest that both types of neoadjuvant therapy have similar survival benefits. As current data are heterogeneous and many studies have included significantly different types of patients in their analysis, future studies with better patient selection are still needed to define which neoadjuvant therapy should be chosen. In addition, targeted therapies and immunotherapy have promising results and should be further explored.     

Role of chemotherapy in the treatment of gastroesophageal cancers

Esophageal, gastroesophageal junction, and gastric cancers are underpublicized but are frequently lethal, and gastroesophageal junction adenocarcinomas are increasingly common diseases in the United States and around the world. Although often grouped together in studies of chemotherapy, clear distinctions can be made in the locoregional therapy of these diseases. Esophageal squamous cell carcinomas may be treated with surgery or radiation with concurrent chemotherapy, whereas esophageal adenocarcinomas and gastroesophageal junction adenocarcinomas are often treated with all three treatment modalities. Over the past several years, it has become increasingly evident that gastric cancer is a disease that is potentially sensitive to chemotherapy. In the perioperative setting--at least in the Western world-chemotherapy and sometimes radiation are applied. However, the optimal chemotherapy for advanced gastric or esophageal cancer remains unsettled, and there is no single standard regimen. Several new chemotherapy agents have demonstrated activity in these diseases, but the best chemotherapy remains to be determined. This paper will review the role of chemotherapy in gastroesophageal cancers.     

Dual tumor‐suppressors miR‐139‐5p and miR‐139‐3p targeting matrix metalloprotease 11 in bladder cancer

Our recent study of the microRNA (miRNA) expression signature of bladder cancer (BC) by deep‐sequencing revealed that two miRNA, microRNA‐139‐5p/microRNA‐139‐3p were significantly downregulated in BC tissues. The aim of this study was to investigate the functional roles of these miRNA and their modulation of cancer networks in BC cells. Functional assays of BC cells were performed using transfection of mature miRNA or small interfering RNA (siRNA). Genome‐wide gene expression analysis, in silico analysis and dual‐luciferase reporter assays were applied to identify miRNA targets. The associations between the expression of miRNA and its targets and overall survival were estimated by the Kaplan–Meier method. Gain‐of‐function studies showed that miR‐139‐5p and miR‐139‐3p significantly inhibited cell migration and invasion by BC cells. The matrix metalloprotease 11 gene (MMP11) was identified as a direct target of miR‐139‐5p and miR‐139‐3p. Kaplan–Meier survival curves showed that higher expression of MMP11 predicted shorter survival of BC patients (P = 0.029). Downregulated miR‐139‐5p or miR‐139‐3p enhanced BC cell migration and invasion in BC cells. MMP11 was directly regulated by these miRNA and might be a good prognostic marker for survival of BC patients.     

The role of surgery in the multidisciplinary management of patients with localized gastrointestinal stromal tumors

Surgical resection of localized gastrointestinal stromal tumors (GISTs) is associated with recurrence rates of approximately 50% at 5 years of follow-up. The introduction of tyrosine kinase inhibitors, such as imatinib, improved overall survival rates in advanced disease, while in the adjuvant setting, improved recurrence-free survival following resection of high-risk GIST. The demonstration of the clinical benefit of tyrosine kinase inhibitors in both the metastatic and adjuvant settings generated interest in neoadjuvant approaches for patients with operable locally advanced disease, particularly in difficult anatomic locations. The potential impact of tumor downsizing in areas such as the gastroesophageal junction, the duodenum or the rectum, on the extent of surgical resection and morbidity is real. The ongoing research regarding neoadjuvant therapy, the duration of adjuvant therapy and the optimal means by which to risk stratify patients with GIST continues to keep the treatment of this disease at the forefront of personalized cancer care.     

Regulation of ITGA3 by the anti‐tumor miR‐199 family inhibits cancer cell migration and invasion in head and neck cancer

For patients with head and neck squamous cell carcinoma (HNSCC), survival rates have not improved due to local recurrence and distant metastasis. Current targeted molecular therapies do not substantially benefit HNSCC patients. Therefore, it is necessary to use advanced genomic approaches to elucidate the molecular mechanisms underlying the aggressiveness of HNSCC cells. Analysis of our microRNA (miRNA) expression signature by RNA sequencing showed that the miR‐199 family (miR‐199a‐5p, miR‐199a‐3p, miR‐199b‐5p and miR‐199b‐3p) was significantly reduced in cancer tissues. Ectopic expression of mature miRNA demonstrated that all members of the miR‐199 family inhibited cancer cell migration and invasion by HNSCC cell lines (SAS and HSC3). These findings suggested that both passenger strands and guide strands of miRNA are involved in cancer pathogenesis. In silico database and genome‐wide gene expression analyses revealed that the gene coding for integrin α3 (ITGA3) was regulated by all members of the miR‐199 family in HNSCC cells. Knockdown of ITGA3 significantly inhibited cancer cell migration and invasion by HNSCC cells. Moreover, overexpression of ITGA3 was confirmed in HNSCC specimens, and high expression of ITGA3 predicted poorer survival of the patients (P = 0.0048). Our data revealed that both strands of pre‐miR‐199a (miR‐199a‐5p and miR‐199a‐3p) and pre‐miR‐199b (miR‐199b‐5p and miR‐199b‐3p) acted as anti‐tumor miRNA in HNSCC cells. Importantly, the involvement of passenger strand miRNA in the regulation of cellular processes is a novel concept in RNA research. Novel miRNA‐based approaches for HNSCC can be used to identify potential targets for the development of new therapeutic strategies.