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Tumor metastasis is a key factor affecting the life of patients with malignant tumors. For the past hundred years, scientists have been focusing on how to kill cancer cells and inhibit their metastasis in vivo, but few breakthroughs have been made. Here we propose a novel mode for cancer metastasis. Here we show that the phagocytosis of apoptotic tumor cells by macrophages leads to their polarization into the M2 phenotype, and that the expression of stem cell related as well as drug resistance genes are induced. Therefore, it appears that M2 macrophages have "defected" and have been transformed into the initial "metastatic cancer cells", and thus are the source of the distal tissue tumor metastasis. This conclusion is supported by the presence of fused cells with both macrophage and tumor cell characteristics in the peripheral blood and ascites of patients with ovarian cancer. By suppressing the expression of CD206 in M2 macrophages by siRNA, we show that the growth and metastasis of tumors is suppressed at the in vitro cell line and in the in vivo experimental mice models. In summary, we show that M2 macrophages in the blood circulation undergo a "change of loyalty" to become "cancer cells" that undergo distal tissue metastasis, which can be suppressed by the knockdown of CD206 expression.

STUDY QUESTION What are the features of FAM71D (Family with sequence similarity 71, member D) expression and is there an association between FAM71D expression and sperm motility? SUMMARY ANSWER FAM71D, a novel protein exclusively expressed in the testis, is located in sperm flagella and is functionally involved in sperm motility. WHAT IS KNOWN ALREADY Some testis-specific proteins have been reported as potential diagnostic biomarkers to evaluate the spermatogenesis process and sperm quality. We have identified a novel testis-specific protein, FAM71D, through microarray data analysis, yet little is known about its expression and function. STUDY DESIGN, SIZE, DURATION FAM71D mRNA and protein expression was quantified during mouse testis development. Its localization in germ cells was detected by dual-labeled immunostaining in testis sections and sperm smears. The clinical significance was assessed by comparing FAM71D expression in spermatozoa from normozoospermic controls and asthenozoospermic patients. PARTICIPANTS/MATERIALS, SETTING, METHODS Testes were dissected from C57BL/6 J male mice at postnatal ages of 1, 2, 3, 4, 6, 8 weeks and 6 months, and sperm was collected from cauda epididymides of adult mice by the swim-up method. Human spermatozoa were isolated from 100 human semen samples by density gradient Percoll centrifugation. RT-qPCR and western blot were performed to semi-quantify the expression of FAM71D in mouse testis, and in the ejaculated spermatozoa of normozoospermic controls and asthenozoospermic patients. Immunofluorescence staining was used to detect the localization of FAM71D. Co-immunoprecipitation assay was performed to evaluate the interaction between FAM71D and calmodulin. An antibody blocking assay was employed to assess the role of FAM71D in sperm motility. MAIN RESULTS AND THE ROLE OF CHANCE Our results showed that FAM71D was exclusively expressed in the testis in an age-dependent manner. FAM71D expression exhibited dynamic change in the cytoplasm of spermatids during spermiogenesis and was finally retained in sperm flagella. FAM71D could interact with calmodulin. Use of anti-FAM71D antibody on sperm significantly decreased sperm motility. Expression level of FAM71D was markedly reduced in the ejaculated spermataozoa of asthenozoospermic patients (P < 0.05), and this was correlated with sperm progressive motility (r = 0.7435, P < 0.0001). LARGE SCALE DATA N/A. LIMITATIONS, REASONS FOR CAUTION The sample size was limited and it is necessary to verify the correlation of FAM71D expression with sperm motility in larger cohorts. Furthermore, our results were descriptive and follow-up studies would be needed to elucidate the detailed role of FAM71D in sperm motility. WIDER IMPLICATIONS OF THE FINDINGS This is the first systematic study to document the expression of endogenous FAM71D and a function for FAM71D in sperm motility. It provides new insights into our understanding of sperm motility regulation and causes of male infertility. STUDY FUNDING/COMPETING INTERESTS This study was funded by the National Natural Science Foundation of China, Guangdong Natural Science Foundation and the Shenzhen Project of Science and Technology. The authors have no competing interests.

Sturge-Weber syndrome (SWS) is a rare neurocutaneous disorder whose etiology remains unclear. To investigate the genetic contribution underlying this disease, the genetic variants of a 4-generation family with a history of SWS was analyzed in the present study. SWS was diagnosed in 3 of the family members (II-1, III-11 and IV-6). Sanger sequencing was performed to identify mutations in G protein subunit αq (GNAQ) and RAS p21 protein activator 1 exons in the 3 patients with SWS and other unaffected family members. Notably, a non-synonymous single-nucleotide variant at codon 183 on exon 4 of the GNAQ gene was identified as the only pathogenic site. This variant generated a substitution of arginine (R) with glutamine and resulted in a change of function of the encoded protein. Evolutionary conservation analysis revealed that the mutated residue 183 (R) of GNAQ is highly conserved across several vertebrate species. Furthermore, an immunofluorescence staining assay demonstrated that the substitution of arginine with glutamine resulted in a change in the sub-cellular localization of the GNAQ recombinant protein in vitro. These findings may aid in the development of novel diagnostic markers and/or therapeutic targets for the treatment of patients with familial SWS.

Objective:The aim of this study was to evaluate whether ubiquitin-specific peptidase 26 (USP26) gene variations were associated with nonobstructive azoospermia (NOA).Methods:Seven hundred and seventy-six patients diagnosed with NOA and 709 proven fertile men were included in this study. Genetic variations of infertility-related genes, including USP26, were identified by selected exonic sequencing. The effects of USP26 mutations on androgen receptor (AR) binding, ubiquitination, and transcriptional activity were detected by immunoprecipitation and luciferase assay in Hela and TM4 cells.Results:Six novel missense mutations and 1 novel synonymous mutation of USP26 unique to the patients with NOA were identified. Of these missense mutations, USP26 R344W remarkably reduced the binding affinity and deubiquitinating activity of USP26 to AR, thus eliminated the inhibitory effect of USP26 on transcriptional activity of AR in Hela and TM4 cells.Conclusion:A novel USP26 variant p.R344W is associated with NOA probabl...

Nuclear receptor subfamily 0 group B member 1 (Nr0b1) is an atypical member of the nuclear receptor family that is predominantly expressed in mouse Sertoli cells (SCs). Mutations of NR0B1 in humans cause adrenal failure and hypogonadotropic hypogonadism. The targeted mutagenesis of Nr0b1 in mice has revealed a primary gonadal defect characterized by the overexpression of aromatase and cellular obstruction of the seminiferous tubules and efferent ductules, leading to germ cell death and infertility. The transgenic expression of Nr0b1 under the control of the Müllerian-inhibiting substance promoter (MIS-Nr0b1), which is selectively expressed in SCs, improves fertility. Testicular androgen receptor (AR) was also expressed in SCs. Many genes are directly regulated by androgen and its AR, which are involved in spermatogenesis and male infertility. As the association between NR0B1 and AR remains unclear in mouse SCs, we decided to further explore the relationship between them. In the present study, we have identified NR0B1 as a novel AR co-repressor in mouse SCs. Using RT‑qPCR and immunofluorescence, we determined that NR0B1 was mainly expressed in mouse SCs in an age-dependent manner from 2-8 weeks of age postnatally. The inhibition of the effects of AR on AR target genes by NR0B1, in an androgen‑dependent manner, was further demonstrated by western blot analysis and RT-qPCR in TM4 cells, a mouse Sertoli cell line. Finally, in vitro luciferase and co-immunoprecipitation assays validated that NR0B1, as an AR co-repressor, significantly inhibited the transcriptional activation of its target genes. These results suggest that novel inhibitory mechanisms underlie the effects of NR0B1 in modulating androgen-dependent gene transcription in mouse SCs.

Renal cell carcinoma (RCC) is the most common type of kidney cancer in adults, which is associated with poor prognosis and high recurrence. Long non‑coding RNAs (lncRNAs) have been reported to be dysregulated in cancer and to be important in the regulation of carcinogenesis, thus suggesting that this class of molecules may be used as biomarkers in cancer. The lncRNA urothelial carcinoma associated 1 (UCA1) has been observed to be upregulated and to function as an oncogene in certain types of cancer; however, the role of UCA1 in RCC remains to be elucidated. The present study aimed to determine the expression and function of UCA1 in RCC. Quantitative polymerase chain reaction (qPCR) was used to determine the expression levels of UCA1 in 46 paired RCC and adjacent normal tissue samples. Furthermore, qPCR was used to determine the expression levels of UCA1 in four RCC cell lines compared with the human embryonic kidney 293T cell line. The impact of UCA1 on cell migration, proliferation and apoptosis was investigated by wound scratch assay, MTT and flow cytometry, respectively. The results of the present study demonstrated that UCA1 expression levels were significantly increased in RCC tissues and cells, as compared with the controls. Ectopic expression and gene silencing of UCA1 in RCC cell lines exerted opposite effects on cellular proliferation, migration and apoptosis, and the results suggested that UCA1 may function as an oncogene in RCC. These results indicated that UCA1 may be considered as a promising biomarker for diagnosis, and a therapeutic target in RCC. Further research is required to elucidate the role and target genes of UCA1 in RCC.

Renal cell carcinoma (RCC) is the most common type of kidney cancer in adults and is associated with a poor prognosis due to a lack of early‑warning signs, protean clinical manifestations, and resistance to radiotherapy and chemotherapy. Recently, increasing evidence has suggested that microRNAs (miRNAs) are involved in the proliferation, invasion and apoptosis of various types of human cancer cells. In a previous study, miRNA expression profiles from renal cell carcinoma (RCC) revealed that expression of miR‑20b‑5p was significantly downregulated in RCC tissues. The aim of this study was to investigate the expression and functional significance of miR‑20b‑5p in RCC. The expression of miR‑20b‑5p was quantified in 48 paired RCC tissues and cell lines, and compared with adjacent normal tissues and the 293T cell line by reverse transcription‑quantitative polymerase chain reaction. The functional impact of miR‑20b‑5p on cell proliferation, cell migration and apoptosis in the 786‑O and ACHN RCC cell lines, was determined by an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, a scratch assay and flow cytometry. To the best of our knowledge, the present study was the first to reveal that miR‑20b‑5p was downregulated in RCC tissues and cell lines. It also demonstrated that upregulation of miR‑20b‑5p inhibited cellular migration and proliferation, and promoted cellular apoptosis, suggesting that miR‑20b‑5p functioned as a potential tumor suppressor. However, further studies are required to fully determine the effects of miR‑20b‑5p and the miR‑20b‑5p‑mediated molecular pathway in RCC and other types of cancer. In conclusion, these results imply that miR‑20b‑5p may be a biomarker for early detection and prognosis prediction, as well as a therapeutic target for RCC.

Androgens and the androgen receptor (AR) are of great importance to spermatogenesis and male fertility. AR knockout (ARKO) mice display a complete insensitivity to androgens and male infertility, however, the exact molecular mechanism for this effect remains unclear. In this study, we found that the expression levels of Prmt6 mRNA and protein were significantly up-regulated in the testes of ARKO mice compared to wild type (WT) mice. PRMT6 was principally localized to the nucleus of spermatogonia and spermatocytes by immunofluorescence staining. Furthermore, luciferase assay data showed that AR together with testosterone treatment suppressed Prmt6 transcription via binding to the androgen-responsive element (ARE) of the Prmt6 promoter. Moreover, knockdown of Prmt6 suppressed germ cells migration and promoted apoptosis. In addition, both of these cellular activities could not be enhanced by testosterone treatment. Taken together, these data indicate that PRMT6, which was down-regulated by AR and influenced cell migration and apoptosis of germ cells, could play a potentially important role in spermatogenesis.

MicroRNAs (miRNAs/miRs) serve an important role in the regulation of carcinogenic pathways. RCC is the most prevalent kidney cancer that occurs in adults. miRNAs have gained increasing attention due to their association with RCC tumorigenesis, serving as biomarkers for early detection and progression monitoring, and as potential targets for molecular therapy. Upregulation of miRNA-142-3p has been previously identified in RCC tissues by microarray profile, however, its expression and function in RCC have not yet been validated. In the present study, quantitative polymerase chain reaction was performed to quantify the relative expression of miR-142-3p in 53 paired RCC and adjacent normal tissues. Furthermore, wound healing, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and flow cytometry assays were performed to analyze the impacts of miR-142-3p on cellular migration, proliferation and apoptosis. The results demonstrated that miR-142-3p was significantly upregulated in RCC tissues compared with adjacent normal tissues. Downregulation of miR-142-3p, induced by chemically synthesized miR-142-3p inhibitor, significantly suppressed cell migration and proliferation, and promoted cell apoptosis in 786-O and ACHN cells, supporting the theory that miR-142-3p may function as an oncogene in RCC. The potential clinical significance of miR-142-3p, as a biomarker and therapeutic target, provides rationale for further investigation into the miR-142-3p-mediated molecular pathway and how it is associated with RCC development.

MicroRNAs (miRNAs) have been demonstrated to exhibit abnormal expression patterns in various types of human cancer. The aim of the present study was to identify a novel tumor suppressor microRNA (miR) and investigate its physiological function and mechanism in renal cell carcinoma (RCC). The expression levels of miRNA (miR)‑362‑3p expres were measured in 47 pairs of RCC and adjacent normal tissue samples, using reverse transcription-quantitative polymerase chain reaction analysis. In addition, miR‑362‑3p was transfected into renal cancer cells to investigate its role in the regulation of cell proliferation, migration, invasion, apoptosis and cell cycle. Identification of the target gene of miR‑362‑3p was performed using luciferase reporter assays and western blot analyses. The results demonstrated that the expression levels of miR‑362‑3p were downregulated in the RCC tissue samples, compared with the adjacent normal tissue samples. The upregulation of miR‑362‑3p using a synthesized mimic suppressed the proliferation, migration and invasion of the renal cancer cells, and induced cell apoptosis and G1 phase arrest. Further experiments demonstrated that the overexpression of miR‑362‑3p resulted in decrease expression levels of nemo-like kinase. These results suggested that miR-362-3p functions as a tumor suppressor in RCC, and may serve as a potential molecular target in the treatment of RCC.

MicroRNA (miR)-510-5p has been demonstrated to be involved in a number of types of malignancy; however, the function of miR-510-5p in renal cancer remains unclear. The present study aimed to determine the expression of miR-510-5p in renal cell carcinoma (RCC) specimens and analyzed the impact of miR-510-5p on renal cancer by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, wound scratch and apoptosis assays. The results showed that miR-510-5p was significantly downregulated in RCC specimens compared with normal renal specimens. Overexpression of miR-510-5p by synthetic mature mimics reduced cell proliferation and migration and induced an increase in cell apoptosis, indicating that miR-510-5p may act as a tumor suppressor in RCC. The present study firstly revealed that downregulated miR-510-5p functioned as a tumor suppressor by reducing cellular proliferation and migration, and inducing apoptosis in RCC. Further research is required to define target genes of miR-510-5p to determine the cellular mechanism of miR-510-5p in the carcinogenesis of RCC.

Nasopharyngeal carcinoma has very high incidence and high mortality worldwide. MiRNA is related to the tumorigenesis and metastasis of a variety of tumors. In the present study, we verify that the expression of miR-494 in NPC tissues and NPC-derived cells was down-regulated, respectively. The proliferation, colony formation, migration, and invasion of NPC-derived cells were suppressed, while the cell apoptosis was promoted, when miR-494 was over-expressed in these cells. GALNT7 and CDK16 were confirmed to be the direct targets of miR-494. These results suggested that miR-494 play an inhibitory role in the tumorigenesis of NPC.

MicroRNAs (miRNAs) are known to mainly target protein-coding genes at post-transcriptional level, resulting in mRNA destabilization and/or translational repression. Long non-coding RNAs (lncRNAs) are emerging as a novel set of targets for miRNAs. Here, we report that downregulated hsa-miR-1 and upregulated lncRNA urothelial cancer associated 1 (UCA1) were inversely expressed in bladder cancer. Hsa-miR-1 decreased the expression of UCA1 in bladder cancer cells in an Ago2-slicer-dependent manner. The binding site between UCA1 and hsa-miR-1 was confirmed. Overexpression of hsa-miR-1 inhibited bladder cancer cell growth, induced apoptosis, and decreased cell motility. Knockdown of UCA1 expression phenocopied the effects of upregulation of hsa-miR-1. Transfection of UCA1 expression vector partly reversed the changes caused by transfection of pre-miR-1 plasmids. This study provides evidence for hsa-miR-1 to play tumor suppressive roles via downregulating lncRNA UCA1 in bladder cancer, which may have potential therapeutic significance.

Phenotype-driven mutagenesis is an unbiased method to identify novel genes involved in spermatogenesis and other reproductive processes. Male repro29/repro29 mice generated by the Reproductive Genomics Program at the Jackson Laboratory were infertile with deformed sperm and poor motility. Using selected exonic capture and massively parallel sequencing technologies, we identified a nonsense mutation in the exon 6 of coiled-coil domain-containing 62 gene (Ccdc62), which results in a formation of a premature stop codon and a truncated protein. Among the tissues examined, CCDC62 was found to be expressed at the highest level in mouse testis by reverse transcriptase-PCR (RT-PCR) and Western blot analysis. With immunofluorescent staining, we demonstrated that CCDC62 was expressed in the cytoplasm and the developing acrosome in the spematids of mouse testis, and was specifically localized at the acrosome in mature sperm. The complementation analysis by mating repro29/+ mice with Ccdc62 -/- mice (generated by CRISPR-Cas9 strategy) further provided genetic proof that the infertility of repro29/repro29 mice was caused by Ccdc62 mutation. Finally, it was found that intracellular colocalization and interaction of CCDC62 and Golgi-associated PDZ and coiled-coil motif-containing protein may be important for acrosome formation. Taken together, this study identified a nonsense mutation in Ccdc62, which directly results in male infertility in repro29/repro29 mice.

Teratozoospermia is generally associated with clinical infertility. Despite numerous studies, the molecular mechanisms underlying male infertility are still poorly understood. In the present study, we demonstrated that deletion of Spata46, a gene encoding a novel protein of unknown function found in mouse testis, was responsible for male subfertility, and the cause of subfertility was characterized as abnormal sperm head shape and a failure of sperm-egg fusion. We also demonstrated that SPATA46 was expressed predominantly in condensed spermatids, with a highly specific localization restricted to the subacrosomal area; the protein is located at the nuclear membrane due to a transmembrane region in the N-terminus of the protein. At the subcellular level, SPATA46-deficient condensed spermatids displayed structural defects consisting of a discontinuous nuclear envelope and a cavity in the nucleus associated with an abnormal nuclear shape. Additionally, in vitro, we determined that the absence of SPATA46 led to accumulation of sperm around the perivitelline space of eggs, and the same phenomenon was also observed for natural sperm incubated with an anti-SPATA46 antibody, suggesting functional relevance of SPATA46 for sperm-egg fusion. Taken together, these results indicated that SPATA46 is a novel protein involved in reshaping of the sperm head and sperm-egg fusion.

MicroRNAs (miRs) are small, endogenous noncoding RNAs that serve a significant function in various biologic processes, including those involved in cancer. The present study aimed to determine the expression and function of miR-16 in renal cell carcinoma (RCC). Quantitative polymerase chain reaction was used to quantify the expression of miR-16 in 48 paired RCC tissues and adjacent normal tissues. The impact of miR-16 on cell proliferation, migration and apoptosis was analyzed by transfecting miR-16 mature molecules into the renal cancer cell lines 786-O and ACHN. The results indicated that miR-16 was significantly upregulated in RCC tissues (P

Hyperoxia and pulmonary infections are well known to increase the risk of acute and chronic lung injury in newborn infants, but it is not clear whether hyperoxia directly increases the risk of pneumonia. The purpose of this study was to examine: (1) the effects of hyperoxia and antioxidant enzymes on inflammation and bacterial clearance in mononuclear cells and (2) developmental differences between adult and neonatal mononuclear cells in response to hyperoxia. Mouse macrophages were exposed to either room air or 95% O2 for 24 h and then incubated with Pseudomonas aeruginosa. After 1 h, bacterial adherence, phagocytosis, and macrophage inflammatory protein (MIP)-1alpha production were analyzed. Bacterial adherence increased 5.8-fold (p0.0001), phagocytosis decreased 60% (p0.05), and MIP-1alpha production increased 49% (p0.05) in response to hyperoxia. Overexpression of MnSOD or catalase significantly decreased bacterial adherence by 30.5%, but only MnSOD significantly improved bacterial phagocytosis and attenuated MIP-1alpha production. When monocytes from newborns and adults were exposed to hyperoxia, phagocytosis was impaired in both groups. However, adult monocytes were significantly more impaired than neonatal monocytes. Data indicate that hyperoxia significantly increases bacterial adherence while impairing function of mononuclear cells, with adult cells being more impaired than neonatal cells. MnSOD reduces bacterial adherence and inflammation and improves bacterial phagocytosis in mononuclear cells in response to hyperoxia, which should minimize the development of oxidant-induced lung injury as well as reducing nosocomial infections.

Renal cell carcinoma (RCC) is the most common kidney cancer in adults and has a poor prognosis. cAMP responsive element binding protein 1 (CREB1) is a proto‑oncogenic transcription factor involved in malignancies of various organs. However, its functional role(s) have not yet been elucidated in RCC. We investigated the expression pattern, function and regulation of CREB1 in RCC. CREB1 was overexpressed in the RCC tissues and cell lines. Downregulation of CREB1 inhibited RCC tumorigenesis by affecting cell proliferation, migration and apoptosis. Multiple computational algorithms predicted that the 3'‑untranslated region (3'‑UTR) of human CREB1 mRNA is a target for miR‑10b‑5p and miR‑363‑3p. Luciferase reporter assay, qPCR and western blot analysis confirmed that miR‑10b‑5p and miR‑363‑3p bind directly to the 3'‑UTR of CREB1 mRNA and inhibit mRNA and protein expression of CREB1. qPCR data also revealed a significantly lower expression of miR‑10b‑5p and miR‑363‑3p in RCC tissues. Introduction of miR‑10b‑5p and miR‑363‑3p mimics led to suppressed expression of CREB1 and inhibited cell proliferation, migration and apoptosis reduction. Taken together, we propose that CREB1 is an oncogene in RCC and that upregulation of CREB1 by loss of tumor suppressive miR‑10b‑5p and miR‑363‑3p plays an important role in the tumorigenesis of RCC.

Renal cell carcinoma (RCC) is the most common type of malignant tumor of the adult kidney and has a poor prognosis. MicroRNAs (miRs) are important in a wide range of biological and pathological processes, including cell differentiation, migration, growth, proliferation, apoptosis and metabolism. The present study aimed to determine the role exerted by miR‑30a‑5p in the tumorigenesis of RCC. The expression levels of miR‑30a‑5p in RCC tissues and RCC‑derived cells were demonstrated to be significantly downregulated by real‑time quantitative polymerase chain reaction (RT‑qPCR). Wound scratch assay, cell proliferation assay and flow cytometric analysis revealed that the abilities of migration and proliferation of the RCC‑derived cells were suppressed, whereas cell apoptosis was promoted, when miR‑30a‑5p was overexpressed in these cells. N‑acetylgalactosaminyltransferase 7 (GALNT7) was predicted to be one target gene of miR‑30a‑5p by bioinformatics analysis. Luciferase reporter assay, RT‑qPCR and western blotting were performed to confirm that GALNT7 is the direct conserved target of miR‑30a‑5p. These results suggested that miR‑30a‑5p has a tumor‑suppressive role in the tumorigenesis of RCC.

Reactive oxygen species (ROS) can cause cell injury and death via mitochondrial-dependent pathways, and supplementation with antioxidants has been shown to ameliorate these processes. The c-Jun NH2-terminal kinase (JNK) pathway has been shown to play a critical role in ROS-induced cell death. To determine if targeting catalase (CAT) to the mitochondria provides better protection than cytosolic expression against H2O2-induced injury, the following two approaches were taken: 1) adenoviral-mediated transduction was performed using cytosolic (CCAT) or mitochondrial (MCAT) CAT cDNAs and 2) stable cell lines were generated overexpressing CAT in mitochondria ( n = 3). Cells were exposed to 250 μM H2O2, and cell survival, mitochondrial function, cytochrome c release, and JNK activity were analyzed. Although all viral transduced cells had a transient twofold increase in CAT activity, MCAT cells had significantly higher survival rates, the best mitochondrial function, and lowest JNK activity compared with CCAT and LacZ controls. The improved protection with MCAT was observed in primary type II lung epithelial cells and in transformed lung epithelial cells. In the three stable cell lines, cell survival directly correlated with extent of mitochondrial localization ( r = 0.60572, P < 0.05) and not overall CAT activity ( r = −0.45501, P < 0.05). Data indicate that targeting of antioxidants directly to the mitochondria is more effective in protecting lung epithelial cells against ROS-induced injury. This has important implications in antioxidant supplementation trials to prevent ROS-induced lung injury in critically ill patients.

Prolonged exposure to supraphysiological oxygen concentrations results in the generation of reactive oxygen species, which can cause significant lung injury in critically ill patients. Supplementation with human recombinant antioxidant enzymes (AOE) may mitigate hyperoxic lung injury, but it is unclear which combination and concentration will optimally protect pulmonary epithelial cells. First, stable cell lines were generated in alveolar epithelial cells (MLE12) overexpressing one or more of the following AOE: Mn superoxide dismutase (MnSOD), CuZnSOD, or glutathione peroxidase 1. Next, A549 cells were transduced with 50–300 particles/cell of recombinant adenovirus containing either LacZ or each of the three AOE (alone or in combination). Cells were then exposed to 95% O2 for up to 3 days, with cell number and viability determined daily. Overexpression of either MnSOD (primarily mitochondrial) or CuZnSOD (primarily cytosolic) reversed the growth inhibitory effects of hyperoxia within the first 48 h of exposure, resulting in a significant increase in viable cells ( P < 0.05), with 1.5- to 3-fold increases in activity providing optimal protection. Protection from mitochondrial oxidation was confirmed by assessing aconitase activity, which was significantly improved in cells overexpressing MnSOD ( P < 0.05). Data indicate that optimal protection from hyperoxic injury occurs in cells coexpressing MnSOD and glutathione peroxidase 1, with prevention of mitochondrial oxidation being a critical factor. This has important implications for clinical trials in preterm infants receiving SOD supplementation to prevent acute and chronic lung injury.

Oxidant insults can lead to apoptotic and nonapoptotic cell death. Lung epithelial cells exposed to high levels of oxygen do not die via apoptosis, but through a much slower, morphologically distinct process involving cell and nuclear swelling. In contrast, H2O2 induces a rapid apoptotic cell death. We first assessed the effect of oxidant exposure on activator protein-1 (c-Jun and Fos) and c-Jun N-terminal kinase (JNK) regulation in MLE12 cells. Both oxidants induced c-Jun and Fos expression, albeit with a different pattern of regulation-hyperoxia (95% O2) induced a biphasic response, whereas H2O2 (500 microM) induced a sustained response. We then examined the role of JNK by Western blot, JNK activity assay, and a pull-down assay and observed an identical pattern of regulation. To assess whether JNK functions in a pro-death or pro-survival capacity, we generated stable cell lines that constitutively express a dominant-negative mutation of JNK resulting in significant inhibition of JNK activity. Inhibition of the JNK pathway in this manner prevented hyperoxic and H2O2-induced cell death. These results demonstrate that hyperoxic cell death is pathway-driven and that both modes of death involve the JNK signaling pathway.

microRNAs (miRs) have been investigated as a novel class of regulators of cellular processes, including proliferation, apoptosis and metabolism. In particular, miR‑30b has been demonstrated to be deregulated in certain types of cancer, including lung, colorectal and gastric cancer. Previous studies of miR‑30b in renal clear cell carcinoma demonstrated that the expression level of miR‑30b was associated with distant metastasis. However, the function of miR‑30b in renal cell carcinoma (RCC) remained to be elucidated. In the present study, the expression of miR‑30b in 31 paired RCC tissues from four cell lines (786‑O, 769‑P, ACHN and 293T) was detected by reverse transcription‑quantitative polymerase chain reaction. In addition, the effect of miR‑30b on cell proliferation in RCC cells was also determined using MTT and Cell Counting Kit‑8 assay analyses. Furthermore, the function of miR‑30b in cell migration and invasion was determined by wound scratch and Transwell assays. Flow cytometry was also performed to quantify the effect of miR‑30b on cell apoptosis. The results of the current study indicated that miR‑30b was upregulated in RCC tissues from affected cell lines when compared with adjacent normal tissues and a normal kidney cell line, which is different to the downregulation of miR‑30b as observed in other types of cancer. miR‑30b is associated with RCC cell proliferation, invasion, migration and apoptosis, which indicated that miR‑30b acts as an oncogene in RCC. To the best of our knowledge, the present study is the first to demonstrate the upregulation of miR‑30b in RCC tissues and describe miR‑30b as an oncogene in RCC in the regulation of cell proliferation, migration, invasion and apoptosis. Further studies will define the target gene of miR‑30b in RCC and investigate the potential role of miR‑30b as a biomarker for RCC.

Kidney cancer is the 14th most common cancer in the world and its prognosis remains poor due to difficult early detection and treatment. Therefore, the identification of biomarkers for early-stage renal cell carcinoma (RCC) is important. MicroRNA-106b (miR-106b) has been described as an oncogene in several types of human cancer. Previous microarray studies have suggested that miR-106b was significantly upregulated in RCC tissues compared with paired normal kidney tissues and may be a promising biomarker for the prediction of early metastasis following nephrectomy. The present study aimed to determine the expression and function of miR-106b in RCC. The expression of miR-106b in RCC tissues and cells, and in paired normal tissues and cells was determined by reverse transcription quantitative polymerase chain reaction, based on the previous sequencing results of miRNAs. Furthermore, a wound scratch assay, MTT assay and flow cytometry were performed to examine the functions of miR-106b on cell migration, proliferation and apoptosis. The results demonstrated that miR-106b was upregulated in RCC tissues and cell lines compared with control normal tissues and cell lines. Downregulation of miR-106b with a synthesized inhibitor suppressed cell migration and proliferation and induced renal cancer cell apoptosis, suggesting that miR-106b can be characterized as an oncogene in RCC. To the best of our knowledge, the present study was the first to reveal that miR-106b is upregulated and affects cellular migration, proliferation and apoptosis in RCC. Further studies are required to examine the role and target genes of miR-106b in RCC.

Clear cell renal cell carcinoma (ccRCC) is the predominant and most aggressive type of kidney malignancy, however, the mechanism underlying its carcinogenesis remains to be elucidated. The present study aimed to determine the expression and function of microRNA (miR)‑429 in ccRCC carcinogenesis. Reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) was used to detect the expression of miR‑429 in ccRCC specimens. Following transfection of miR‑429 synthetic mimics, the expression of miR‑429 was examined and cell proliferation, cell migration, apoptosis and luciferase assays were conducted in ccRCC cell lines. The results demonstrated that expression of miR‑429 was decreased in ccRCC cells. In addition, upregulation of miR‑429 by transfection of mimics reduced cellular proliferation and migration, and induced apoptosis in ACHN and 786‑0 cell lines. Furthermore, miR‑429 decreased the 3'UTR luciferase activity of vascular endothelial growth factor (VEGF) and c‑MYC, and RT‑qPCR analysis demonstrated that the cancer cells transfected with miR‑429 mimics exhibited decreased expression of VEGF, but not c‑MYC. To the best of our knowledge, the present study was the first to reveal that downregulated miR‑429 functioned as a tumor suppressor by restraining cellular proliferation and migration, and inducing apoptosis, as well as targeting VEGF in ccRCC cells.

To determine whether overexpression of antioxidant enzymes in lung epithelial cells prevents damage from oxidant injury, stable cell lines were generated with complementary DNAs encoding manganese superoxide dismutase (MnSOD) and/or catalase (CAT). Cell lines overexpressing MnSOD, CAT, or MnSOD + CAT were assessed for tolerance to hyperoxia or paraquat. After exposure to 95% O(2) for 10 d, 44 to 57% of cells overexpressing both MnSOD and CAT and 37 to 47% of cells overexpressing MnSOD alone were viable compared with 7 to 12% of empty vector or parental cells (P < 0.05). To assess if viable cells were capable of cell division after hyperoxic exposures (up to 5 d), a clonogenicity assay was performed. The clonogenic potential of cells overexpressing MnSOD + CAT and MnSOD alone were significantly better than those expressing CAT alone or empty vector controls. In addition, 54 to 72% of cells overexpressing both MnSOD and CAT survived in 1 mM paraquat compared with 58 to 73% with MnSOD alone and 27% with control cells. Overexpression of CAT alone did not improve survival in hyperoxia or paraquat. The combination of MnSOD + CAT did not provide additional protection from paraquat. Data demonstrate that overexpression of MnSOD protects cells from oxidant injury and CAT offers additional protection from hyperoxic injury when co-expressed with MnSOD.

'Epigenetics' is defined as the inheritable changes in gene expression with no alterations in DNA sequences. Epigenetics is a rapidly expanding field, and the study of epigenetic regulation in cancer is emerging. Disruption of the epigenome is a fundamental mechanism in cancer, and several epigenetic drugs have been proven to prolong survival and to be less toxic than conventional chemotherapy. Promising results from combination clinical trials with DNA methylation inhibitors and histone deacetylase inhibitors have recently been reported, and data are emerging that describe molecular determinants of clinical responses. Despite significant advances, challenges remain, including a lack of predictive markers, unclear mechanisms of response and resistance, and rare responses in solid tumors. Preclinical studies are ongoing with novel classes of agents that target various components of the epigenetic machinery. In the present review, examples of studies that demonstrate the role of epigenetic regulation in human cancers with the focus on histone modifications and DNA methylation, and the recent clinical and translational data in the epigenetics field that have potential in cancer therapy are discussed.

We examined the cooperative activity between the Sp1 and NF-kappa B/Rel sites of the human immunodeficiency virus type 1 long terminal repeat in response to phorbol 12-myristate 13-acetate (PMA) stimulation in an in vitro transcription assay. Sp1 sites alone do not account for the activation induced by PMA. When mutations in Sp1 sites were combined with mutations in the NF-kappa B/Rel sites, a dramatic reduction in PMA-induced transcriptional activity was observed. This reduction was much greater than the reduction associated with mutations involving only the NF-kappa B/Rel sites. This finding suggests that there is functional cooperation between Sp1 and NF-kappa B/Rel and that this is one possible mechanism for transcription activation by NF-kappa B/Rel. The three AP1 sites in the negative regulatory region of the long terminal repeat, however, seem to be uninvolved in the earliest moments of transcriptional activation by PMA.

In this report we introduce a simple, fast, and reliable method to prepare whole cell or nuclear extracts from small numbers of cells. These extracts were used to study transcriptional activation of the human immunodeficiency virus type 1 (HIV-1) long terminal repeat (LTR) in vitro. Our results revealed that the time courses of activation of extracts derived from cells stimulated with the mitogenic lectin phytohemagglutinin (PHA) or with the tumor promoter phorbol 12-myristate 13-acetate (PMA) are different. PMA induces a rapid onset of increased in vitro transcription from the HIV-1 LTR, while PHA causes a slow and sustained response. The biochemical relevance of protein synthesis inhibition by cycloheximide treatment of cells was investigated. In these studies, PMA induction of a change in in vitro transcriptional activity is not dependent on protein synthesis. Cycloheximide alone is insufficient to induce activation. Oligonucleotide-mediated site-directed mutagenesis demonstrated that mutation of the TATA box in the LTR ablated initiation of both basal-level transcription and activation by extracts from cells stimulated with PMA. Surprisingly, mutation of both kappa B sites in the LTR reduced but did not eliminate the in vitro response to extracts prepared at early time points after PHA or PMA stimulation of Jurkat cells. The reduction was greater in extracts derived from cells treated with PMA. Deletion analysis of the HIV-1 LTR revealed at least one region (-464 to -252) capable of suppressing in vitro transcription in extracts from Jurkat cells stimulated by PMA. This result is consistent with early studies of the HIV-1 LTR in transient transfection assays. We therefore have been able to observe distinct regulatory events at early time points after cells are exposed to agents known to induce transcription of both the HIV-1 LTR reporter gene constructs and the HIV-1 provirus itself.

Bacterial infection of the tracheobronchial tree is a frequent, serious complication in patients receiving treatment with oxygen and mechanical ventilation, resulting in increased morbidity and mortality. Using human airway epithelial cell culture models, we examined the effect of hyperoxia on bacterial adherence and the expression of interleukin-8 (IL-8), an important mediator involved in the inflammatory process. A 24-h exposure to 95% O2increased Pseudomonas aeruginosa (PA) adherence 57% in A549 cells ( P < 0.01) and 115% in 16HBE cells ( P < 0.01) but had little effect on Staphylococcus aureus (SA) adherence. Exposure to hyperoxia, followed by a 1-h incubation with SA, further enhanced PA adherence ( P < 0.01), suggesting that hyperoxia and SA colonization may enhance the susceptibility of lung epithelial cells to gram-negative infections. IL-8 expression was also increased in cells exposed to both hyperoxia and PA. Stable or transient overexpression of manganese superoxide dismutase reduced both basal and stimulated levels of PA adherence and IL-8 levels in response to exposure to either hyperoxia or PA. These data indicate that hyperoxia increases susceptibility to infection and that the pathways are mediated by reactive oxygen species. Therapeutic intervention strategies designed to prevent accumulation of intracellular reactive oxygen species may reduce opportunistic pulmonary infections.