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Cisplatin is one of the most effective chemotherapy drugs for ovarian cancer, but resistance is common. The initial response to platinum‑based chemotherapy is as high as 80%, but in most advanced patients, final relapse and death are caused by acquired drug resistance. The development of resistance to therapy in ovarian cancer is a significant hindrance to therapeutic efficacy. The resistance of ovarian cancer cells to chemotherapeutic mechanisms is rather complex and includes multidrug resistance, DNA damage repair, cell metabolism, oxidative stress, cell cycle regulation, cancer stem cells, immunity, apoptotic pathways, autophagy and abnormal signaling pathways. The present review provided an update of recent developments in our understanding of the mechanisms of ovarian cancer platinum‑based chemotherapy resistance, discussed current and emerging approaches for targeting these patients and presented challenges associated with these approaches, with a focus on development and overcoming resistance.

Various disease severity scoring systems were currently used in critically ill patients with acute respiratory failure, while their performances were not well investigated. The study aimed to investigate the difference in prognosis predictive value of 4 different disease severity scoring systems in patients with acute respiratory failure. With a retrospective cohort study design, adult patients admitted to intensive care unit (ICU) with acute respiratory failure were screened and relevant data were extracted from an open-access American intensive care database to calculate the following disease severity scores on ICU admission: acute physiology score (APS) III, Sequential Organ Failure Assessment score (SOFA), quick SOFA (qSOFA), and Oxford Acute Severity of Illness Score (OASIS). Hospital mortality was chosen as the primary outcome. Multivariable logistic regression analyses were performed to analyze the association of each scoring system with the outcome. Receiver operating characteristic curve analyses were conducted to evaluate the prognosis predictive performance of each scoring system. A total of 4828 patients with acute respiratory failure were enrolled with a hospital mortality rate of 16.78%. APS III (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.02–1.03), SOFA (OR 1.15, 95% CI 1.12–1.18), qSOFA (OR 1.26, 95% CI 1.11–1.42), and OASIS (OR 1.06, 95% CI 1.05–1.08) were all significantly associated with hospital mortality after adjustment for age and comorbidities. Receiver operating characteristic analyses showed that APS III had the highest area under the curve (AUC) (0.703, 95% CI 0.683–0.722), and SOFA and OASIS shared similar predictive performance (area under the curve 0.653 [95% CI 0.631–0.675] and 0.664 [95% CI 0.644–0.685], respectively), while qSOFA had the worst predictive performance for predicting hospital mortality (0.553, 95% CI 0.535–0.572). These results suggested the prognosis predictive value varied among the 4 different disease severity scores for patients admitted to ICU with acute respiratory failure.

miR-34a is an important molecule that can inhibit the tumor growth. This study aimed to investigate the functional role of miR-34a in hepatocellular carcinoma (HCC) and explore the interaction between miR-34a and histone deacetylase 1 (HDAC1). RT-qPCR was employed to detect the mRNA expression of miR-34a and HDAC1 in 60 HCC tissues. Results showed miR-34a expression in HCC tissues was significantly lower than in normal tissues (P

Histone deacetylase 2 (HDAC2) is crucial for embryonic development, affects cytokine signaling relevant for immune responses, and is often significantly overexpressed in solid tumors, but little is known of its role in human lung cancer. In this study, we demonstrated the aberrant expression of HDAC2 in lung cancer tissues and investigated oncogenic properties of HDAC2 in human lung cancer cell lines. HDAC2 inactivation resulted in regression of tumor cell growth and activation of cellular apoptosis via p53 and Bax activation and Bcl2 suppression. In cell cycle regulation, HDAC2 inactivation caused induction of p21WAF1/CIP1 expression, and simultaneously suppressed the expressions of cyclin E2, cyclin D1, and CDK2, respectively. Consequently, this led to the hypophosphorylation of pRb protein in G1/S transition and thereby inactivated E2F/DP1 target gene transcriptions of A549 cells. In addition, we demonstrated that HDAC2 directly regulated p21WAF1/CIP1 expression in a p53-independent manner. However, HDAC1 was not related to p21WAF1/CIP1 expression and tumorigenesis of lung cancer. Lastly, we observed that sustained-suppression of HDAC2 in A549 lung cancer cells attenuated in vitro tumorigenic properties and in vivo tumor growth of the mouse xenograft model. Taken together, we suggest that the aberrant regulation of HDAC2 and its epigenetic regulation of gene transcription in apoptosis and cell cycle components play an important role in the development of lung cancer.

MicroRNAs (miRNA) play important regulatory roles in the occurrence and development of cancers. This study aimed to investigate the effects of miR-26a on the proliferation and apoptosis of ovarian cancer cells and explore the potential mechanism. qRT-PCR was performed to measure the miR-26a expression in 46 ovarian cancer tissues, and results showed miR-26a expression reduced significantly when compared with normal ovarian tissues (P

The mammalian homolog of yeast Sir2 protein is the sirtuin family of histone deacetylases (HDACs), a NAD+-dependent protein deacetylase in humans. Accumulating evidence suggests that sirtuin 2 (SIRT2) co-localizes with the microtubule network and deacetylates α-tubulin, and is involved in various cellular processes including calorie restriction-dependent life span extension, mitotic cell cycle regulation, cellular apoptosis, DNA damage repair, and genomic silencing. However, the underlying mechanisms of action remains poorly understood, especially in hepatocarcinogenesis. Hence in this study, to determine the association between the aberrant expression of SIRT2 and liver cancer development and progression, SIRT2 expression was investigated in ten selected hepatocellular carcinoma (HCC) tissues and matched normal liver tissues, using RT-PCR and Western blot analysis. Next, SIRT2 was disrupted by siRNA-mediated protein knockdown method to investigate the biological role of SIRT2 in hepatocarcinogenesis in Hep3B cells. As a result, we identified that SIRT2 expression was significantly up-regulated in HCC tissues compared to corresponding normal liver tissues. In addition, suppression of SIRT2 caused regression of tumor cell growth and proliferation. We also found that SIRT2 could interact with α-tubulin and regulates the acetylation status of α-tubulin in Hep3B cells. In conclusion, we suggest that SIRT2 is aberrantly regulated in HCCs which may contribute to the mitogenic potential of tumor cells during the development and progression of HCC, and could be a novel molecular target for therapeutic intervention in liver cancer.

In a previous report we demonstrated that the transcriptomic response of liver tissue was specific to toxicants, and a characteristic molecular signature could be used as an early prognostic biomarker in rats. It is necessary to determine the transcriptomic response to toxicants in peripheral blood for application to the human system. Volatile organic compounds (VOCs) comprise a major group of pollutants which significantly affect the chemistry of the atmosphere and human health. In this study we identified and validated the specific molecular signatures of toxicants in rat whole blood as early predictors of environmental toxicants. VOCs (dichloromethane, ethylbenzene, and trichloroethylene) were administered to 11-week-old SD male rats after 48 h of exposure, peripheral whole blood was subjected to expression profiling analysis. Unsupervised gene expression analysis resulted in a characteristic molecular signature for each toxicant, and supervised analysis identified 1,217 outlier genes as distinct molecular signatures discerning VOC exposure from healthy controls. Further analysis of multi-classification suggested 337 genes as early detective molecular markers for three VOCs with 100% accuracy. A large-scale gene expression analysis of a different VOC exposure animal model suggested that characteristic expression profiles exist in blood cells and multi-classification of this VOC-specific molecular signature can discriminate each toxicant at an early exposure time. This blood expression signature can thus be used as discernable surrogate marker for detection of biological responses to VOC exposure in an environment.

The trefoil factor family (TFF) of peptides, which are protease-resistant and have a strong affinity for mucins, play an important role in gastrointestinal mucosal protection and restitution. Prior studies have indicated that dysregulation of TFF2 was associated with cell migration, resistance to apoptosis, and gastric cancer invasion; however, the underlying mechanism associated with these actions remains unclear. Thus, to investigate the relationship between TFF2 and carcinogenesis in gastric cancer, TFF2 expression was analyzed by Western blot analysis in nine selected gastric cancer tissues and immunohistochemical staining was performed in paraffin-embedded samples from 157 gastric cancers. A reduced TFF2 expression was observed by Western blot analysis in the gastric cancer tissues. However, there was no significant difference in the TFF2 expression according to clinical and pathological parameters of the gastric cancers. To investigate the biological role of TFF2 in the development and progression of gastric cancer, a TFF2 expression plasmid was constructed for in vitro experiments of function. Introduction of TFF2 cDNA into a gastric cancer cell line did not affect tumor cell growth, cell migration or invasion. In conclusion, down-regulation of TFF2 in gastric cancer cells and restoration of TFF2 did not affect the tumorigenic potential of gastric cancer cells in vitro. The loss of TFF2 expression might be an early event of the multi-step process of gastrocarcinogenesis and may play a limited role in the mucosal protection of the normal gastric physiology.

The Wnt/beta-catenin signaling pathway regulates various aspects of development and plays important role in human carcinogenesis. Nemo-like kinase (NLK), which is mediator of Wnt/beta-catenin signaling pathway, phosphorylates T-cell factor/lymphoid enhancer factor (TCF/LEF) factor and inhibits interaction of beta-catenin/TCF complex. Although, NLK is known to be a tumor suppressor in Wnt/beta-catenin signaling pathway of colon cancer, the other events occurring downstream of NLK pathways in other types of cancer remain unclear. In the present study, we identified that expression of NLK was significantly up-regulated in the HCCs compared to corresponding normal tissues in five selected tissue samples. Immunohistochemical analysis showed significant over-expression of NLK in the HCCs. Targeted-disruption of NLK suppressed cell growth and arrested cell cycle transition. Suppression of NLK elicited anti-mitogenic properties of the Hep3B cells by simultaneous inhibition of cyclinD1 and CDK2. The results of this study suggest that NLK is aberrantly regulated in HCC, which might contribute to the mitogenic potential of tumor cells during the initiation and progression of hepatocellular carcinoma; this process appears to involve the induction of CDK2 and cyclin D1 and might provide a novel target for therapeutic intervention in patients with liver cancer.

Objective: This study aimed to investigate expression level of FOXC2 and its relationship to clinical pathological features of renal cell carcinoma (RCC). Methods: The expression levels of FOXC2 in RCC tissues and normal renal tissues (62 samples, respectively) were detected by immunohistochemistry and PCR Array. Statistics analyses were done with SPSS to compare the differences between RCC tissues and normal renal tissue, and to explore the relationship between the expression level of FOXC2 and the clinical pathological features of RCC. Results: Expression level of FOXC2 in RCC tissues was significantly higher than in normal renal tissues, and other related cancer genes also highly expressed in RCC tissues. FOXC2 expression was positively associated with clinical stage and pathological grade (P < 0.05), but not significantly related to the gender and age (P > 0.05). Conclusion: The expression of FOXC2 in renal cell carcinoma was significantly higher than that in normal renal tissues. It is suggested that FOXC2 might play a crucial role in the occurrence and development of RCC and could be an important prognostic indicator for clinical therapy.

Histone deacetylases (HDACs) are known to play a central role in the regulation of several cellular properties interlinked with the development and progression of cancer. Recently, HDAC1 has been reported to be overexpressed in hepatocellular carcinoma (HCC), but its biological roles in hepatocarcinogenesis remain to be elucidated. In this study, we demonstrated overexpression of HDAC1 in a subset of human HCCs and liver cancer cell lines. HDAC1 inactivation resulted in regression of tumor cell growth and activation of caspase-independent autophagic cell death, via LC3B-II activation pathway in Hep3B cells. In cell cycle regulation, HDAC1 inactivation selectively induced both p21(WAF1/Cip1) and p27(Kip1) expressions, and simultaneously suppressed the expression of cyclin D1 and CDK2. Consequently, HDAC1 inactivation led to the hypophosphorylation of pRb in G1/S transition, and thereby inactivated E2F/DP1 transcription activity. In addition, we demonstrated that HDAC1 suppresses p21(WAF1/Cip1) transcriptional activity through Sp1-binding sites in the p21(WAF1/Cip1) promoter. Furthermore, sustained suppression of HDAC1 attenuated in vitro colony formation and in vivo tumor growth in a mouse xenograft model. Taken together, we suggest the aberrant regulation of HDAC1 in HCC and its epigenetic regulation of gene transcription of autophagy and cell cycle components. Overexpression of HDAC1 may play a pivotal role through the systemic regulation of mitotic effectors in the development of HCC, providing a particularly relevant potential target in cancer therapy.

Histone deacetylase 2 (HDAC2) is crucial for embryonic development, affects cytokine signaling relevant for immune responses and is often significantly overexpressed in solid tumors; but little is known about its role in human hepatocellular carcinoma (HCC). In this study, we showed that targeted-disruption of HDAC2 resulted in reduction of both tumor cell growth and de novo DNA synthesis in Hep3B cells. We then demonstrated that HDAC2 regulated cell cycle and that disruption of HDAC2 caused G1/S arrest in cell cycle. In G1/S transition, targeted-disruption of HDAC2 selectively induced the expression of p16(INK4A) and p21(WAF1/Cip1), and simultaneously suppressed the expression of cyclin D1, CDK4 and CDK2. Consequently, HDAC2 inhibition led to the down-regulation of E2F/DP1 target genes through a reduction in phosphorylation status of pRb protein. In addition, sustained suppression of HDAC2 attenuated in vitro colony formation and in vivo tumor growth in a mouse xenograft model. Further, we found that HDAC2 suppresses p21(WAF1/Cip1) transcriptional activity via Sp1-binding site enriched proximal region of p21(WAF1/Cip1) promoter. In conclusion, we suggest that the aberrant regulation of HDAC2 may play a pivotal role in the development of HCC through its regulation of cell cycle components at the transcription level providing HDAC2 as a relevant target in liver cancer therapy.

Gastric carcinoma is the most common neoplasm in Southeast Asian populations and is the second leading cause of cancer death worldwide. Annexins are a family of cytosolic calcium and membrane binding proteins that have been implicated in a wide variety of cell functions. Recent studies have suggested that Annexin A10 (ANXA10), a member of the Annexin protein family, is down-regulated in specific types of cancer. However, the underlying molecular mechanisms of the dysregulation of ANXA10 remain to be elucidated. In the present study, to investigate the biological effects of ANXA10 on gastric carcinoma, aberrant expression of ANXA10 was evaluated by Western blot analysis, reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC), in gastric cancer tissues and cell lines. Decreased expression of ANXA10 was observed in five selected gastric cancer tissues compared to the normal surrounding mucosa. In the cancer cell lines, seven out of nine selected gastric cancer cell lines had no detectable ANXA10 by RT-PCR. Among these, when an ANXA10 expressing plasmid was introduced into MKN-1 cells, cell growth was suppressed and apoptosis augmented. The results of this study demonstrated that ANXA10 was aberrantly regulated in gastric carcinoma and suggests that down-regulation of ANXA10 might be involved in gastric carcinogenesis. In addition, ANXA10 may play a role, as a tumor suppressor, in the development and progression of gastric cancer.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer death worldwide. The number of cases of HCC has continued to increase in recent decades. Previous studies have suggested that S100P, a member of the S100P calcium-binding protein family, is aberrantly regulated in several malignant neoplasms. However, the underlying molecular mechanisms of the dysregulation of S100P remain to be elucidated. To investigate biological effects of S100P on hepatocarcinogenesis, aberrant expression of S100P was investigated by immunohistochemistry (IHC), Western blot analysis and reverse transcriptase-polymerase chain reaction (RT-PCR) in HCC tissues and cell lines. Endogenous expression of S100P was disrupted by the RNA interference-mediated protein knockdown method in the human Hep3B liver cancer cell line. Then, cell growth and cellular apoptosis were compared with control siRNA transfectants. The effects of S100P-silencing on the major components of cell cycle regulation were assessed by Western blot analysis. As results, elevated levels of S100P were observed in the HCC tissues compared to the corresponding normal tissues. Targeted disruption of S100P suppressed cell growth and augmented cellular apoptosis. In addition, inhibition of S100P resulted in the down-regulation of cyclinD1 and CDK2. In conclusion, this study showed over-expression of S100P in HCC. The aberrant regulation of S100P in HCC might activate cyclin D1 and CDK expression and contribute to the mitogenic potential of tumor cells during HCC carcinogenesis. These findings provide information that suggests new therapeutic strategies for the treatment of liver cancer.

The transforming growth factor receptor III (TGFbetaRIII) is the most abundant and essential TGF-beta binding protein that functions as a co-receptor with other receptors in TGF-beta signaling. In earlier studies, expression of TGFbetaRIII was reported to be decreased in a variety of human cancers. Functional assessment of TGFbetaRIII was performed in many previously studied cancers but not in hepatocellular carcinoma. Therefore, in this study, we investigated the expression and genetic alterations of TGFbetaRIII in hepatocellular carcinoma (HCC) by quantitative real-time PCR (qRT-PCR) and single-strand conformation polymorphism (SSCP) analysis. The qRT-PCR showed down-regulation of TGFbetaRIII in the tumor samples. To investigate whether genetic alterations mediated decreased expression of TGFbetaRIII, we performed mutation analysis of 67 human HCC tissues by SSCP and direct sequencing. We found five previously reported and one novel single nucleotide polymorphisms in exons 2, 3, 5, 13 and 14, but no mutations were detected. These polymorphisms were not associated with amino acid changes except for a base change found in exon 2 (TCC--TTC, S15F). The loss of heterozygosity (LOH) analysis performed on 10 tumors and corresponding normal pairs, showed a low rate of LOH (2/10). The results of this study suggest that TGFbetaRIII is transcriptionally down-regulated in hepatocellular carcinoma. In addition, genetic alterations did not appear to be associated with the reduced expression level of TGFbetaRIII. To clarify the role of TGFbetaRIII in hepatocellular tumor development and progression, functional analysis is needed in future studies.

The transforming growth factor receptor III (TGFbetaRIII) is the most abundant and essential TGF-beta binding protein that functions as a co-receptor with other receptors in TGF-beta signaling. In earlier studies, expression of TGFbetaRIII was reported to be decreased in a variety of human cancers. Functional assessment of TGFbetaRIII was performed in many previously studied cancers but not in hepatocellular carcinoma. Therefore, in this study, we investigated the expression and genetic alterations of TGFbetaRIII in hepatocellular carcinoma (HCC) by quantitative real-time PCR (qRT-PCR) and single-strand conformation polymorphism (SSCP) analysis. The qRT-PCR showed down-regulation of TGFbetaRIII in the tumor samples. To investigate whether genetic alterations mediated decreased expression of TGFbetaRIII, we performed mutation analysis of 67 human HCC tissues by SSCP and direct sequencing. We found five previously reported and one novel single nucleotide polymorphisms in exons 2, 3, 5, 13 and 14, but no mutations were detected. These polymorphisms were not associated with amino acid changes except for a base change found in exon 2 (TCC-->TTC, S15F). The loss of heterozygosity (LOH) analysis performed on 10 tumors and corresponding normal pairs, showed a low rate of LOH (2/10). The results of this study suggest that TGFbetaRIII is transcriptionally down-regulated in hepatocellular carcinoma. In addition, genetic alterations did not appear to be associated with the reduced expression level of TGFbetaRIII. To clarify the role of TGFbetaRIII in hepatocellular tumor development and progression, functional analysis is needed in future studies.

Histone deacetylase (HDAC) inhibitors are emerging as an exciting new class of potential anti-cancer agents for the treatment of solid and hematological malignancies. However, the best characterized HDAC function concerns the control of gene expression via the regulation of transcription activation or repression. To understand the genome-wide effects of HDAC inhibition on gene regulation, we performed serial gene expression analyses from 0 to 48 h after treating MDA-MB-435, a melanoma-derived highly metastatic tumor cell line, with Apicidin, a HDAC inhibitor. Combined-transcriptomic analysis of large-scale molecular changes induced by Apicidin resulted in the identification of 631 outlier genes that were continuously up- or down-regulated during the 48 h study period. When the 631 outlier genes were mapped to known biological processes, cell-cycle suppression emerged as the function most elicited by Apicidin. In addition comprehensive negative cell-cycle regulation by Apicidin was dissected using gene expression data and validated by Western blot analysis. We suggest the 631 outlier genes as a characteristic molecular signature for Apicidin, and propose concurrent transcriptional suppression of major components of cell-cycle regulatory circuit as potent anti-tumor mechanism of Apicidin. Genetic elements identified during this study also provide the possibility of novel therapeutic interventions in tumor metastasis.

The wnt/β-catenin signaling pathway regulates various aspects of development and plays important role in human carcinogenesis. Nemo-like kinase (NLK), which is mediator of wnt/β-catenin signaling pathway, phosphorylates T-cell factor/lymphoid enhancer factor (TCF/LEF) factor and inhibits interaction of β-catenin/TCF complex. Although, NLK is known to be a tumor suppressor in wnt/β-catenin signaling pathway of colon cancer, the other events occurring downstream of NLK pathways in other types of cancer remain unclear. In the present study, we identified that expression of NLK was significantly up-regulated in the HCCs compared to corresponding normal tissues in five selected tissue samples. Immunhistochemical analysis showed significant over-expression of NLK in the HCCs. Targeted-disruption of NLK suppressed cell growth and arrested cell-cycle transition. Suppression of NLK elicited anti-mitogenic properties of the Hep3B cells by simultaneous inhibition of cyclinD1 and CDK2. The results of this study suggest that NLK is aberrantly regulated in HCC, which might contribute to the mitogenic potential of tumor cells during the initiation and progression of hepatocellular carcinoma; this process appears to involve the induction of CDK2 and cyclin D1 and might provide a novel target for therapeutic intervention in patients with liver cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1079.