Xiu-Feng Cao

Upregulation of the long non-coding RNA HOTAIR promotes esophageal squamous cell carcinoma metastasis and poor prognosis.

Recent studies of the individual functionalities of long non‐coding RNAs (lncRNAs) in the development and progression of cancer have suggested that HOX transcript antisense RNA (HOTAIR) is capable of reprogramming chromatin organization and promoting cancer cell metastasis. In order to ascertain the expression pattern of the lncRNA HOTAIR and assess its biological role in the development and progression of esophageal squamous cell carcinoma (ESCC), HOTAIR expression in ESCC tissues and adjacent noncancerous tissues were collected from 78 patients and measured by real‐time reverse transcription‐polymerase chain reaction (RT‐PCR). HOTAIR correlation with clinicopathological features and prognosis was also analyzed. Suppression of HOTAIR using siRNA treatment was performed in order to explore its role in tumor progression. Notably elevated HOTAIR expression levels were observed in cancerous tissues compared to adjacent noncancerous tissues (96%, P < 0.01), showing a high correlation with cancer metastasis (P < 0.01), elevated TNM (2009) stage classification (P < 0.01), and lowered overall survival rates (P = 0.003). Multivariate analysis revealed that HOTAIR expression (P = 0.003) is also an independent prognostic factor for comparison of TNM stage (P = 0.024) and lymph node metastasis (P = 0.010). Furthermore, in vitro assays of the ESCC cell line KYSE30 demonstrated that knockdown of HOTAIR reduced cell invasiveness and migration while increasing the response of cells to apoptosis. Thus, HOTAIR is a novel molecule involved in both ESCC progression and prognosis. Full elucidation of HOTAIR functionality relevant to ESCC may open avenues for the use of lncRNAs in identification of novel drug targets and therapies for ESCC and other prevalent cancers.

Identification of the long non-coding RNA POU3F3 in plasma as a novel biomarker for diagnosis of esophageal squamous cell carcinoma

BackgroundRecent studies have demonstrated that long non-coding RNAs (lncRNAs) were present in the blood of cancer patients and have shown great potential as powerful and non-invasive tumor markers. However, little is known about the value of lncRNAs in the diagnosis of esophageal squamous cell carcinoma (ESCC). We hypothesized that ESCC-related lncRNAs might be released into the circulation during tumor initiation and could be utilized to detect and monitor ESCC.MethodsTen lncRNAs (HOTAIR, AFAP1-AS1, POU3F3, HNF1A-AS1, 91H, PlncRNA1, SPRY4-IT1, ENST00000435885.1, XLOC_013104 and ENST00000547963.1) which previously found to be differently expressed in esophageal cancer were selected as candidate targets for subsequent circulating lncRNA assay. A four-stage exploratory study was conducted to test the hypothesis: (1) optimization of detected method to accurately and reproducibly measure ESCC-related lncRNAs in plasma and serum; (2) evaluation of the stability of circulating lncRNAs in human plasma or serum; (3) exploration the origin of ESCC-related lncRNAs in vitro and in vivo; (4) evaluation the diagnostic power of circulating lncRNAs for ESCC.ResultsESCC-related lncRNAs were detectable and stable in plasma of cancer patients, and derived largely from ESCC tumor cells. Furthermore, plasma levels of POU3F3, HNF1A-AS1 and SPRY4-IT1 were significantly higher in ESCC patients compared with normal controls. By receiver operating characteristic curve (ROC) analysis, among the three lncRNAs investigated, plasma POU3F3 provided the highest diagnostic performance for detection of ESCC (the area under the ROC curve (AUC), 0.842; p < 0.001; sensitivity, 72.8%; specificity, 89.4%). Moreover, use of POU3F3 and SCCA in combination could provide a more effective diagnosis performance (AUC, 0.926, p < 0.001, sensitivity, 85.7%; specificity, 81.4%). Most importantly, this combination was effective to detect ESCC at an early stage (80.8%).ConclusionsPlasma POU3F3 could serve as a potential biomarker for diagnosis of ESCC, and the combination of POU3F3 and SCCA was more efficient for ESCC detection, in particular for early tumor screening.

MiR-196a Is Upregulated in Gastric Cancer and Promotes Cell Proliferation by Downregulating p27 kip1

Aberrant expression of miR-196a has been frequently reported in cancer studies. However, the expression and mechanism of its function in gastric cancer remains unclear. Quantitative real-time PCR was carried out to detect the relative expression of miR-196a in gastric cancer cell lines and tissues. SGC7901 cells were treated with miR-196a inhibitors, mimics, or pCDNA/miR-196a to investigate the role of miR-196a in cell proliferation. Higher expression of miR-196a in gastric cancer tissues was associated with tumor size, a higher clinical stage, and was also correlated with shorter overall survival of patients with gastric cancer. Exogenous downregulation of miR-196a expression significantly suppressed the in vitro cell-cycle progression, proliferation, and colony formation of gastric cancer cells, and ectopic miR-196a expression significantly enhanced the development of tumors in nude mice. Luciferase assays revealed that miR-196a inhibited p27kip1 expression by targeting one binding site in the 3′-untranslated region (3′-UTR) of p27kip1 mRNA. qPCR and Western blot assays verified that miR-196a reduced p27kip1 expression at both mRNA and protein levels. The p27kip1-mediated repression in cell proliferation was reverted by exogenous miR-196a expression. A reverse correlation between miR-196a and p27kip1 expression was noted in gastric cancer tissues. Our study shows that aberrant overexpression of miR-196a and consequent downregulation of p27kip1 could contribute to gastric carcinogenesis and would be targets for gastric cancer therapies and further developed as potential prognostic factors. Mol Cancer Ther; 11(4); 842–52. ©2012 AACR.

Long noncoding RNA SPRY4-IT1 is upregulated in esophageal squamous cell carcinoma and associated with poor prognosis

LncRNA SPRY4-IT1 has been shown to promote the progression of melanoma. However, the role of lncRNA SPRY4-IT1 in human esophageal squamous cell carcinoma (ESCC) remains unclear. The purpose of this study is to investigate the clinical significance and biological functions of SPRY4-IT1 in ESCC. The expression levels of lncRNA SPRY4-IT in 92 ESCC patients and 8 ESCC cell lines were evaluated by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). The prognostic significance was evaluated using Kaplan–Meier and Cox regression analyses. Small interfering RNA (siRNA) was used to suppress SPRY4-IT1 expression in ESCC cell lines. Both in vitro and in vivo assays were performed to further explore its role in tumor progression. SPRY4-IT1 levels were significantly higher in ESCC tissues and cells than in corresponding adjacent noncancerous tissues and nontumorigenic esophageal epithelial cells, and the ESCC patients with higher SPRY4-IT1 expression had an advanced clinical stage and poorer prognosis than those with lower SPRY4-IT1 expression. The multivariate analysis revealed that SPRY4-IT1 expression level is an independent prognostic factor in ESCC patients. In vitro assays demonstrated that knockdown of SPRY4-IT1 reduced cell proliferation, invasiveness, and migration. In vivo assays demonstrated that knockdown of SPRY4-IT1 decreases cell growth. SPRY4-IT1 is a novel molecule involved in ESCC progression, which may provide a potential prognostic biomarker and a potential target for therapeutic intervention.

Association of decreased expression of long non-coding RNA LOC285194 with chemoradiotherapy resistance and poor prognosis in esophageal squamous cell carcinoma

BackgroundExpression of the long non-coding RNA (lncRNA) LOC285194 was previously shown to be correlated with aggressive clinicopathological features and poor prognosis in several cancers. The aim of the present study was to explore the relationship between LOC285194 expression and clinical outcomes in esophageal squamous cell carcinoma (ESCC), so as to assess whether it could be a novel biomarker for prognosis and prediction of response to therapy on ESCC patients.MethodsThe method of quantitative real-time polymerase chain reaction (qRT-PCR) was used to measure LOC285194 expression in pretreatment biopsy specimens and matched normal tissue derived from ESCC patients who underwent preoperative chemoradiotherapy followed by surgical resection (CRT + S group; n = 55) or from those who received surgical resection alone (S group; n = 87). The association between LOC285194 expression and clinicopathological features and prognosis were then analyzed.ResultsLOC285194 expression was significantly down-regulated in ESCC tumor tissues when compared with the adjacent normal tissues (p < 0.001). Low expression of LOC285194 was associated with larger tumor size (p = 0.002), advanced TNM stage (p = 0.018), more lymph node metastases (p = 0.013) and distant metastases (p = 0.015). In the CRT + S group, the pathological complete response rate was 57% (16/28) for the LOC285194-high group, and 15% (4/27) for the LOC285194-low group. Univariate analysis revealed that low expression of LOC285194 was significantly correlated with CRT response (p = 0.002). Moreover, Kaplan-Meier survival analysis revealed that patients with low expression of LOC285194 had a decreased disease free survival (DFS) (p < 0.001) and overall survival (OS) (p < 0.001). Multivariable analysis further identified low expression of LOC285194 as an independent prognosis factor for CRT response (p = 0.011), DFS (p < 0.001) and OS (p = 0.002).ConclusionDecreased expression of LOC285194 could serve as a molecular marker to predict the clinical outcome of ESCC patients after surgery, and select patients who would benefit from preoperative CRT.

Effects of neoadjuvant radiochemotherapy on pathological staging and prognosis for locally advanced esophageal squamous cell carcinoma

The role of neoadjuvant therapy in the treatment of locally advanced esophageal carcinoma still remains controversial. The aim of this study was to evaluate the effects of neoadjuvant radiochemotherapy on pathological staging and prognosis in the patients with locally advanced esophageal squamous cell carcinoma. Between January 1991 and December 2000, 473 patients with advanced esophageal carcinoma diagnosed by endoscopic biopsy underwent surgical resection in our center. With informed consent, they were randomized into four groups: neoadjuvant chemotherapy, neoadjuvant radiotherapy, neoadjuvant radiochemotherapy, and surgery alone (control group). The preoperative computed tomography staging criteria were the following: Stage I, the tumor limited to the esophageal lumen or the thickness of the esophageal wall varied between 3-5 mm; Stage II, the thickness exceeds 5 mm but no invasion to the mediastinum or distant metastasis; Stage III, the tumor invades adjacent mediastinal structure; and Stage IV, there is distant metastasis. The tumor resection rate, pathological stage, treatment-related complication, and survival among groups were compared. The radical resection rate for the patients in radiotherapy and radiochemotherapy groups was increased in comparison with the control group (P < 0.05). Their pathological stage after esophagectomy was regressed significantly than that of the control group (50.85%, 55.08% vs. 0%, P < 0.05). The adjuvant chemotherapy group did show significant improvement on resection rate and pathological staging compared with the control group. The treatment-related complication in the three neoadjuvant groups had no significant difference from that of the control group (P > 0.05). The 3-year survival rate of radiotherapy and radiochemotherapy groups were significantly higher than that of the control group (69.49%, 73.73% vs. 53.38%, P < 0.05). The 5-year survival rate of radiochemotherapy group was higher than that of the radiotherapy group although did not show a statistical difference (P > 0.05). Rational application of neoadjuvant radiochemotherapy seems to provide a modest benefit in radical resection and survival in patients with locally advanced esophageal carcinoma.

Distinctive microRNAs in esophageal tumor: early diagnosis, prognosis judgment, and tumor treatment

Esophageal tumor (ET) is aggressive and has poor prognosis. Although the incidence of ET has been reduced by the changing tumor profile, the 5-year survival and mortality rate of ET has not significantly changed, and the outlook has remained bleak. Therefore, new molecular markers for early diagnosis and prognosis judgment are urgently required. In recent years, tumor has been widely regarded as genetic disease along with epigenetic abnormalities. DNA methylation, histone deacetylation, chromatin remodeling, gene imprinting, and noncoding RNA regulation are the major parts of epigenetic regulation. Mounting evidence exists that miRNAs (microRNA), a class of small, endogenous, and non-protein-coding RNAs, provide a novel tool for early clinical diagnosis, prognosis judgment, and gene therapy of ET. In this review, we provide a general overview of the connection between miRNA profiles and their target genes. We also describe in detail in ET from the aspect of clinical insights, the potential application of miRNAs as biomarkers, potential diagnostic and therapeutic tools.

HOTAIR regulates HK2 expression by binding endogenous miR-125 and miR-143 in oesophageal squamous cell carcinoma progression

Esophageal Squamous Cell Carcinoma (ESCC) is one of the most common malignant cancers worldwide with a high death rate worldwide. Long non-coding RNA (LncRNA) has been recently demonstrated to play a critical role in ESCC. LncRNA HOTAIR played important regulatory roles in ESCC. We highlight the molecular mechanisms by which HOTAIR could influence the expression of Hexokinase 2 (HK2) in ESCC through binding miR-125 and miR-143 directly. Taken together, this study identified a functional lncRNA HOTAIR involved with regulation of glycolysis via miRNA-125/miRNA-143-HK2 in ESCC cells. The “competitive endogenous RNA” (ceRNA) model of HOTAIR/miR-125 and miR143/HK2 interaction might serve as important targets for ESCC diagnosis and therapy.

Association of Wnt1/β-Catenin with Clinical Pathological Characteristics and Prognosis of Esophageal Squamous Cell Carcinoma

The aim of this study was to investigate the correlation between Wnt1/beta-catenin expression and the clinicopathologic features and prognosis of patients with esophageal squamous cell carcinoma (ESCC). The mRNA and protein expression levels of Wnt1/beta-catenin genes in 70 ESCC and 15 adjacent noncancerous paraffin-embedded samples were determined by real-time quantitative polymerase chain reaction and immunohistochemical staining. The mRNA expression level of Wnt1/beta-catenin in ESCC was significantly higher than that in the adjacent noncancerous tissues (1.9934 +/- 1.9888 vs. 0.8863 +/- 0.665, p = 0.0184; 0.2854 +/- 0.1298 vs. 0.0128 +/- 0.0158, p = 0.0000, respectively), and the overexpression of Wnt1/beta-catenin mRNA was aggressively associated with lymph node metastasis and advanced pathological stage (p < 0.0001). The protein expression level of Wnt1/beta-catenin was also significantly higher than that in the adjacent noncancerous tissues (0.3830 +/- 0.0947 vs. 0.2721 +/- 0.1474, p = 0.0002; 0.2835 +/- 0.0844 vs. 0.2352 +/- 0.0670, p = 0.0210, respectively); however, the overexpression was not associated with clinicopathologic characteristics. Meanwhile, the protein expression level of Wnt1 had no relevance with that of beta-catenin. The overexpression of Wnt1/beta-catenin might be an important molecular marker to predict the clinicopathologic stage and prognosis of ESCC, and the level of Wnt1/beta-catenin mRNA was conversely correlated with lymph node metastasis and advanced pathological stage. The overexpression of Wnt1/beta-catenin mRNA should also predict poor prognosis of ESCC; however, it might not be an independent prognostic factor.

SPSB3 targets SNAIL for degradation in GSK-3β phosphorylation-dependent manner and regulates metastasis

Epithelial-mesenchymal transition (EMT) is a process during which normal epithelial cells acquire mesenchymal characteristics. EMT has a critical role in various human diseases especially in cancer. EMT facilitates tumor initiation and progression by mediating cancer cell stemness and motility. Zinc finger transcription factor SNAIL is one of the most important initiators of EMT. Therefore, it is of great significance to understand the regulating mechanism of SNAIL. In this study, we carried out a luciferase-based genome-wide screening using small interfering RNA library against ~200 of E3 ligases and ubiquitin-related genes and identified SOCS box protein SPSB3 as a novel E3 ligase component that targets SNAIL into polyubiquitination and degradation in response to GSK-3β phosphorylation of SNAIL. Functionally, we observed that SPSB3 overexpression greatly inhibits tumor metastasis by regulating SNAIL degradation both in vitro and in vivo. The expression of SPSB3 and SNAIL are negatively correlated in human esophageal squamous cell carcinoma tissues, and low SPSB3 expression indicates lymph node metastasis. Moreover, high SPSB3 expression indicates good survivals in various kinds of cancer. Collectively, these findings suggest that SPSB3-mediated SNAIL degradation has a vital role in regulating EMT and cancer progression.