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Background: Hepatocellular carcinoma (HCC) is one of the most common malignant cancers with poor prognosis and high incidence. The clinical data analysis of liver hepatocellular carcinoma samples downloaded from The Cancer Genome Atlas reveals that the THO Complex 1 (THOC1) is remarkable upregulated in HCC and associated with poor prognosis. However, the underlying mechanism remains to be elucidated. We hypothesize that THOC1 can promote the proliferation of HCC. The present study aims to identify THOC1 as the target for HCC treatment and broaden our sights into therapeutic strategy for this disease. Methods: Quantitative RT-PCR, Western blot, immunofluorescence and immunohistochemistry were used to measure gene and protein expression. Colony formation and cell cycle analysis were performed to evaluate the proliferation. The gene set enrichment analysis were performed to identify the function which THOC1 was involved in. The effects of THOC1 on the malignant phenotypes of hepatocellular cells were examined in vitro and in vivo. Results: The gene set enrichment analysis reveals that THOC1 can promote the proliferation and G2/M cell cycle transition of HCC. Similarly, experimental results demonstrate that THOC1 promotes HCC cell proliferation and cell cycle progression. The knockdown of THOC1 leads to R-loop formation and DNA damage and confers sensitivity to cisplatin. In addition, in vivo data demonstrate that THOC1 can enhance tumorigenesis by increasing tumor cell proliferation. Furthermore, virtual screening predicts that THOC1 as a direct target of luteolin. Luteolin can induce DNA damage and suppress the proliferation of HCC by targeting THOC1. Furthermore, the inhibition of THOC1 activity by luteolin enhances the chemosensitivity of HCC tumor cells to cisplatin. Conclusions: THOC1 was identified as a predictive biomarker vital for HCC-targeted treatments and improvement of clinical prognosis. Luteolin combined with cisplatin can effectively suppress HCC tumor growth, indicating a potential and effective therapeutic strategy that uses luteolin in combination with conventional cytotoxic agents for HCC treatment. [ABSTRACT FROM AUTHOR]

In the original publication of this manuscript [1], Fig. 6 contains a repeated image in error (the left image of 'Migration' and the left image of 'Invasion'). [ABSTRACT FROM AUTHOR]

Background: Esophageal cancer is a high incident cancer worldwide with poor survival and limited therapeutic options. Alterations of microRNAs are common in cancers, and many of these micro RNAs are potential therapeutic and diagnostic targets to treat these cancers. miR-10b-3p located in chromosome region 2q31.1, and its expression is frequently increased in esophageal squamous cell carcinoma (ESCC). However, the biological functions, clinical significance and therapeutic implications of miR-10b-3p in ESCC remain unclear. Methods: The expression levels of miR-10b-3p in ESCC specimens were analyzed by in situ hybridization (ISH) and quantitative reverse transcription polymerase chain reaction (qRT-PCR) assays. Ectopic overexpression of miR-10b-3p in ESCC cells, mouse xenograft model, and metastasis model were used to evaluate the effects of miR-10b-3p on proliferation, and migration of cancer cells. Luciferase reporter assay and Western blot were performed to validate the potential targets of miR-10b-3p after the preliminary screening by computer-aided microarray analysis. Results: We found that miR-10b-3p expression levels were significantly upregulated in the tumor tissues and serum samples of patients with ESCC. The expression levels of miR-10b-3p in both tumor tissues and serum samples were inversely associated with lymph node metastasis and clinical stages. We identified the expression level of miR-10b-3p in ESCC cancer samples as an independent prognostic marker of the overall survival rates of ESCC patients. We found more frequent hypomethylation of the CpG sites located upstream of the miR-10b-3p gene in the ESCC tissues compared with in the adjacent normal tissues, and the DNA methylation status of miR-10b-3p promoter region inversely correlated with the expression levels of miR-10b-3p. Ectopic overexpression of miR-10b-3p promoted cell proliferation, colony formation, migration and invasion in ESCC. While knockdown of miR-10b-3p had the opposite effects, particularly in promoting apoptosis. Mouse xenograft model confirmed that miR-10b-3p functions as a potent oncogenic miRNA in ESCC, which also promoting ESCC metastasis. Mechanistically, we found miR-10b-3p regulated FOXO3 expression by directly binding to the 3′-untranslated region. And systemic delivery of miR-10b-3p antagomir reduced tumor growth and inhibit FOXO3 protein expression in nude mice. Conclusions: Collectively, our findings suggested upregulated expression of miR-10b-3p caused by promoter hypomethylation contributed to the progression of ESCC; Thus, miR-10b-3p is a potentially effective biomarker for ESCC that could have further therapeutic implications. [ABSTRACT FROM AUTHOR]

Background: Epstein-Barr virus (EBV) is widely found in nasopharyngeal carcinoma (NPC) tissue and associated with poor prognosis of patients. EBV nuclear antigen 1 (EBNA1) is expressed in all NPC tumors and plays multiple biological roles in both virus and host cells. Triptolide is a natural product extracted from Tripterygium and shows anti-cancer activities. The goal of this work was to illustrate the anti-cancer effect of triptolide and elucidate a novel anti-apoptotic mechanism of EBNA1 in NPC cells encountered with triptolide. Methods: In the present study, a CCK-8 assay was used to analyze the proliferation of NPC cells treated with triptolide in a dose- and time-dependent ways. Effects of triptolide on NPC cell cycle and apoptosis were investigated by flow cytometric analysis. EBNA1 expression in mRNA and protein levels was determined by quantitative real-time PCR and Western blot, respectively. Results: Our results showed that triptolide effectively inhibited proliferation of NPC cells. Triptolide arrested NPC cell cycles in S phase and induced apoptosis through a caspase-9-dependent apoptosis pathway. Low-dose of triptolide reduced the half-life of EBNA1 and significantly decreased EBNA1 expression by promoting the process of proteasome-ubiquitin pathway. Over-expression of EBNA1, which was independent from EBV genome, effectively attenuated the apoptosis induced by triptolide. In addition, triptolide significantly inhibited proliferations of tumors induced by EBV-positive cells in vivo. Furthermore, EBNA1 were expressed in all NPC biopsies of Chinese patients. Conclusions: In summary, our study provides the evidence that triptolide induces EBNA1 degradation and stimulates NPC apoptosis through mitochondria apoptotic pathway. In addition, EBNA1 assists NPC cells to resist triptolide-induced apoptosis through inhibiting caspase-9-dependent apoptotic pathway. [ABSTRACT FROM AUTHOR]