Radiomic Prediction of CCND1 Expression Levels and Prognosis in Low-grade Glioma Based on Magnetic Resonance Imaging.

OJECTIVES: Low-grade glioma (LGG) is associated with increased mortality owing to recrudescence and the tendency for malignant transformation. Therefore, it is imperative to discover novel prognostic biomarkers as existing traditional prognostic biomarkers of glioma, including clinicopathological features and imaging examinations, are unable to meet the clinical demand for precision medicine. Accordingly, we aimed to evaluate the prognostic value of cyclin D1 (CCND1) expression levels and construct radiomic models to predict these levels in patients with LGG MATERIALS AND METHODS: A total of 412 LGG cases from The Cancer Genome Atlas (TCGA) were used for gene-based prognostic analysis. Using magnetic resonance imaging (MRI) images stored in The Cancer Imaging Archive with genomic data from TCGA, 149 cases were selected for radiomics feature extraction and model construction. After feature extraction, the radiomic signature was constructed using logistic regression (LR) and support vector machine (SVM) analyses. RESULTS: CCND1 was identified as a prognosis-related gene with differential expression in tumor and normal samples and plays a role in regulating both the cell cycle and immune response. Landmark analysis revealed that high-expression levels of CCND1 were beneficial for survival (P < 0.05) in advanced LGG. Four optimal radiomics features were selected to construct radiomics models. The performance of LR and SVM achieved areas under the curve of 0.703 and 0.705, as well as 0.724 and 0.726 in the training and validation sets, respectively. CONCLUSION: Elevated levels of CCND1 expression could impact the prognosis of patients with LGG. MRI-based radiomics, especially the AUC values, can serve as a novel tool for predicting CCND1 expression and understanding the correlation between elevated CCND1 expression and prognosis. AVAILABILITY OF DATA AND MATERIALS: The datasets analyzed during the current study are available in the TCGA, TCIA, UCSC XENA and GTEx repository, https://portal.gdc.cancer.gov/, https://www.cancerimagingarchive.net/, https://xenabrowser.net/datapages/, https://www.gtexportal.org/home/.

Hypoxia promotes metastasis by relieving miR-598-3p-restricted glycolysis in gastric cancer.

The activation of glycolysis, particularly in the context of reprogrammed energy metabolism, is increasingly recognized as a significant characteristic of cancer. However, the precise mechanisms by which glycolysis is promoted in metastatic gastric cancer cells under normal oxygen conditions remain poorly understood. MicroRNAs (miRNAs) play a crucial role in the development of malignant phenotypes in gastric cancer. Nevertheless, our understanding of the specific involvement of miRNAs in hypoxia-induced metabolic shifting and the subsequent metastatic processes is limited. Hypoxia-induced downregulation of miR-598-3p mechanistically leads to the upregulation of RMP and IGF1r, thereby promoting glycolysis. Either overexpression of miR-598-3p or R406 treatment effectively suppresses the metastasis of gastric cancer cells both in vitro and in vivo. Collectively, the depletion of miR-598-3p alters glucose metabolism from oxidative phosphorylation to glycolysis, thereby exacerbating the malignancy of gastric cancer cells. The present findings indicate a potential target for the development of therapeutics against gastric cancers with increased miR-598-3p expression.

Bibliometric and visual analysis of hypoxic pulmonary hypertension from 2013 to 2022.

Hypoxic pulmonary hypertension (HPH) is caused by chronic persistent hypoxia, which leads to the continuous increase of pulmonary artery pressure and pulmonary vascular resistance. In recent years, there has been a substantial increase in research on HPH. To study the trends of HPH research over the last decade, we used WOSCC to search for relevant research on this topic, and dealt with the relevant information using VOSviewer, CiteSpace, and R-tool. Our results show that the number of publications on HPH has generally increased in the last decade, albeit not significantly, while the average number of citations has been declining year by year. Researchers from the USA top the list with 5498 publications, who widely cooperate with researchers from other countries, followed by those from China. Kurt R. Stenmark has an authoritative position in this field, ranking first with 635 citations. American Journal of Physiology Lung Cellular and Molecular Physiology and Pulmonary Circulation have published 151 articles on HPH in the last 10 years, but the former has higher impact factor and article quality. Circulation proved its leadership in this field with 8812 citations. Our findings reveal the trends in HPH research and should provide researchers with plenty of useful information.

Exercise protects aged mice against coronary endothelial senescence via FUNDC1-dependent mitophagy.

Vascular aging contributes to adverse changes in organ function and is a significant indicator of major cardiac events. Endothelial cells (ECs) participate in aging-provoked coronary vascular pathology. Regular exercise is associated with preservation of arterial function with aging in humans. However, the molecular basis is not well understood. The present study was aimed to determine the effects of exercise on coronary endothelial senescence and whether mitochondrial clearance regulator FUN14 domain containing 1 (FUNDC1)-related mitophagy and mitochondrial homeostasis were involved. In mouse coronary arteries, FUNDC1 levels showed gradually decrease with age. Both FUNDC1 and mitophagy levels in cardiac microvascular endothelial cells (CMECs) were significantly reduced in aged mice and were rescued by exercise training. Exercise also alleviated CMECs senescence as evidenced by senescence associated ß-galactosidase activity and aging markers, prevented endothelial abnormal cell migration, proliferation, and eNOS activation in CMECs from aged mice, and improved endothelium-dependent vasodilation of coronary artery, reduced myocardial neutrophil infiltration and inflammatory cytokines evoked by MI/R, restored angiogenesis and consequently alleviated MI/R injury in aging. Importantly, FUNDC1 deletion abolished the protective roles of exercise and FUNDC1 overexpression in ECs with adeno-associated virus (AAV) reversed endothelial senescence and prevented MI/R injury. Mechanistically, PPARγ played an important role in regulating FUNDC1 expressions in endothelium under exercise-induced laminar shear stress. In conclusion, exercise prevents endothelial senescence in coronary arteries via increasing FUNDC1 in a PPARγ-dependent manner, and subsequently protects aged mice against MI/R injury. These findings highlight FUNDC1-mediated mitophagy as potential therapeutic target that prevents endothelial senescence and myocardial vulnerability.

Promotion of Lung Cancer Metastasis by SIRT2-Mediated Extracellular Protein Deacetylation.

Acetylation of extracellular proteins has been observed in many independent studies where particular attention has been given to the dynamic change of the microenvironmental protein post-translational modifications. While extracellular proteins can be acetylated within the cells prior to their micro-environmental distribution, their deacetylation in a tumor microenvironment remains elusive. Here it is described that multiple acetyl-vWA domain-carrying proteins including integrin ß3 (ITGB3) and collagen 6A (COL6A) are deacetylated by Sirtuin family member SIRT2 in extracellular space. SIRT2 is secreted by macrophages following toll-like receptor (TLR) family member TLR4 or TLR2 activation. TLR-activated SIRT2 undergoes autophagosome translocation. TNF receptor associated factor 6 (TRAF6)-mediated autophagy flux in response to TLR2/4 activation can then pump SIRT2 into the microenvironment to function as extracellular SIRT2 (eSIRT2). In the extracellular space, eSIRT2 deacetylates ITGB3 on aK416 involved in cell attachment and migration, leading to a promotion of cancer cell metastasis. In lung cancer patients, significantly increased serum eSIRT2 level correlates with dramatically decreased ITGB3-K416 acetylation in cancer cells. Thus, the extracellular space is a subcellular organelle-like arena where eSIRT2 promotes cancer cell metastasis via catalyzing extracellular protein deacetylation.

URI1 suppresses irradiation-induced reactive oxygen species (ROS) by activating autophagy in hepatocellular carcinoma cells.

Radiotherapy has been extensively applied in cancer treatment. However, this treatment is ineffective in Hepatocellular carcinoma (HCC) due to lack of radiosensitivity. Unconventional prefoldin RPB5 interactor 1 (URI1) exhibits characteristics similar to those oncoproteins, which promotes survival of cancer cells. As a consequence of the irradiation, the levels of endogenous reactive oxygen species (ROS) rise. In the current study, we analyzed the role of URI1 in the control of ROS levels in HepG2 cells. Upon URI1 overexpression, HepG2 cells significantly suppressed irradiation-induced ROS, which may help cells escape from oxidative toxicity. And our data demonstrated that overexpression of URI1 not only resulted in an increase of autophagic flux, but also resulted in an further increased capacity of autophagy to eliminate ROS. It indicated that URI1 suppressed irradiation-induced ROS through activating autophagy. Moreover, URI1 activated autophagy by promoting the activities of AMP-activated protein kinase (AMPK). Results showed that overexpression of URI1 increased the phosphorylation of AMPKα at the Thr172 residue and the activated-AMPK promoted the phosphorylation of forkhead box O3 (FOXO3) at the Ser253 residue, which significantly induced autophagy. Taken together, our findings provide a mechanism that URI1 suppresses irradiation-induced ROS by activating autophagy through AMPK/FOXO3 signaling pathway. These new molecular insights will provide an important contribution to our better understanding about irradiation insensitivity of HCC.

Single-cell spatial transcriptomic analysis reveals common and divergent features of developing postnatal granule cerebellar cells and medulloblastoma.

BACKGROUND: Cerebellar neurogenesis involves the generation of large numbers of cerebellar granule neurons (GNs) throughout development of the cerebellum, a process that involves tight regulation of proliferation and differentiation of granule neuron progenitors (GNPs). A number of transcriptional regulators, including Math1, and the signaling molecules Wnt and Shh have been shown to have important roles in GNP proliferation and differentiation, and deregulation of granule cell development has been reported to be associated with the pathogenesis of medulloblastoma. While the progenitor/differentiation states of cerebellar granule cells have been broadly investigated, a more detailed association between developmental differentiation programs and spatial gene expression patterns, and how these lead to differential generation of distinct types of medulloblastoma remains poorly understood. Here, we provide a comparative single-cell spatial transcriptomics analysis to better understand the similarities and differences between developing granule and medulloblastoma cells. RESULTS: To acquire an enhanced understanding of the precise cellular states of developing cerebellar granule cells, we performed single-cell RNA sequencing of 24,919 murine cerebellar cells from granule neuron-specific reporter mice (Math1-GFP; Dcx-DsRed mice). Our single-cell analysis revealed that there are four major states of developing cerebellar granule cells, including two subsets of granule progenitors and two subsets of differentiating/differentiated granule neurons. Further spatial transcriptomics technology enabled visualization of their spatial locations in cerebellum. In addition, we performed single-cell RNA sequencing of 18,372 cells from Patched+/- mutant mice and found that the transformed granule cells in medulloblastoma closely resembled developing granule neurons of varying differentiation states. However, transformed granule neuron progenitors in medulloblastoma exhibit noticeably less tendency to differentiate compared with cells in normal development. CONCLUSION: In sum, our study revealed the cellular and spatial organization of the detailed states of cerebellar granule cells and provided direct evidence for the similarities and discrepancies between normal cerebellar development and tumorigenesis.

Feasibility and Short-Term Stability of Portal Vein Infusion Port Placement by Transjugular Access.

Six pigs underwent implantation of a portal vein infusion port by transjugular access. The technical success rate was 100% (n = 6), with no surgical complications or deaths. At 1 month after implantation, the catheter tip had moved from the splenic vein to the main portal vein, while the catheter protruded into the right ventricle through the right atrium in all cases. Hence, the infusion port system has not been used in clinical practice due to its obvious displacement after implantation. However, this study provides a new idea for future exploration of portal vein infusion pathways.

RMP/URI inhibits both intrinsic and extrinsic apoptosis through different signaling pathways.

The evading apoptosis of tumor cells may result in chemotherapy resistance. Therefore, investigating what molecular events contribute to drug-induced apoptosis, and how tumors evade apoptotic death, provides a paradigm to explain the relationship between cancer genetics and treatment sensitivity. In this study, we focused on the role of RMP/URI both in cisplatin-induced endogenous apoptosis and in TRAIL-induced exogenous apoptosis in HCC cells. Although flow cytometric analysis indicated that RMP overexpression reduced the apoptosis rate of HCC cells treated with both cisplatin and TRAIL, there was a difference in mechanism between the two treatments. Western blot showed that in intrinsic apoptosis induced by cisplatin, the overexpression of RMP promoted the Bcl-xl expression both in vitro and in vivo. Besides, RMP activated NF-κB/p65(rel) through the phosphorylation of ATM. However, in TRAIL-induced extrinsic apoptosis, RMP significantly suppressed the transcription and expression of P53. Moreover, the forced expression of P53 could offset this inhibitory effect. In conclusion, we presumed that RMP inhibited both intrinsic and extrinsic apoptosis through different signaling pathways. NF-κB was distinctively involved in the RMP circumvention of intrinsic apoptosis, but not in the extrinsic apoptosis of HCC cells. RMP might play an important role in defects of apoptosis, hence the chemotherapeutic resistance in hepatocellular carcinoma. These studies are promising to shed light on a more rational approach to clinical anticancer drug design and therapy.

RMP promotes the proliferation and radioresistance of esophageal carcinoma.

RMP is a RNA polymerase II Subunit RPB-5 associated protein shown to act as an oncogene in several cancer. However, the mechanism of the involvement of RMP in esophageal cancer (EC) remains unclear. We analyzed RMP expression in EC cell lines and EC tissues. The connection between RMP and clinical pathological features of EC was also elucidated. To investigate the role of RMP in EC, We performed CCK-8 assay to evaluate cell proliferation, and Annexin V/PI double-staining to evaluate cell apoptosis. Effect of RMP on tumor progression in nude mouse models was assessed by measurement of volume and weight of tumors. Expression of RMP, CEA and CA199 in vivo were measured by Inmunohistochemical staining. First of all, our study showed that RMP was highly expressed in EC cell lines (compared with normal cells) and tumor tissues (compare with corresponding normal tissues). Then, we found that RMP was bound up with the status of nodal and T stage which indicating that RMP may be related to the growth and malignant degree of EC. Moreover upregulation of RMP could contribute to tumor growth in vitro and vivo. In addition, the results also showed that overexpression of RMP could significantly reduce the susceptibility to radiotherapy. Taken together, all these further suggested that RMP would play a chance-promoting in EC which may provide us a powerful goal for gene targeting treatment of esophageal cancer.

Elongator promotes the migration and invasion of hepatocellular carcinoma cell by the phosphorylation of AKT.

The Elongator is a complex with multiple subunits (Elp1-Elp6) which promotes transcript elongation and protein translation. In this study, we investigated the effects of Elongator on the migration and invasion of HCC cells as well as the underlying mechanisms. We showed that overexpression of Elp3 or Elp4 promoted the migration and invasion of HCC cells, which was abolished when either Elp3 or Elp4 was silenced. The expression of matrix metalloproteinase-2 (MMP-2) and MMP-9 were enhanced by phosphorylation of AKT. Elongator-driven migration and invasion and the expression of MMP-2 and MMP-9 were reduced in HCC cells treated with AKT inhibitor LY294002. Depletion of Elp3 also reduced the phosphorylation of AKT induced by growth factors. In vivo assay of lung metastasis in mice demonstrated that overexpression of Elp3 increased tumor nodules metastatic to lung. Importantly, Elp3 was up-regulated in human HCC tissues, which was correlated with the phosphorylation of AKT and expression of MMP-2. Collectively, these results suggested that Elongator activated migration and invasion of HCC cells by promoting the expression of MMP-2 and MMP-9 through the PI3K/AKT signaling pathway. Our work suggests that Elongator might be a potential marker which promotes the metastasis of HCC.

RMP promotes epithelial-mesenchymal transition through NF-κB/CSN2/Snail pathway in hepatocellular carcinoma.

Epithelial-mesenchymal transition (EMT) is a significant risk factor for metastasis in hepatocellular carcinoma (HCC) patients and with poor prognosis. In this study, we demonstrate the key role of RPB5-mediating protein (RMP) in EMT of HCC cells and the mechanism by which RMP promote EMT. RMP increases migration, invasion, and the progress of EMT of HCC cells, which facilitates the accumulation of Snail, a transcriptional repressor involved in EMT initiation. NF-κB is activated by RMP, which directly promotes the expression of COP9 signalosome 2 (CSN2) to repress the degradation of Snail. Pulmonary metastases mouse model demonstrates that RMP induces metastasis in vivo. Immunohistochemical analysis of human HCC tissues confirms the correlation of RMP with the expression of E-cadherin, p65, CSN2 and Snail in vivo. Collectively, these findings indicate that RMP promotes EMT and HCC metastasis through NF-κB/CSN2/Snail pathway. These results suggest that RMP and p65 may serve as potential candidates of the targets in the treatment of metastatic HCC.

Adenovirus-mediated co-expression of ING4 and PTEN cooperatively enhances their antitumor activity in human hepatocellular carcinoma cells.

Both inhibitor of growth 4 (ING4) and phosphatase and tensin homolog deleted on chromosome 10 (PTEN) are well known as tumor suppressors that are closely related to tumor occurrence and progression. It was reported that ING4 and PTEN showed synergistic antitumor activities in nasopharyngeal carcinoma cells. The two tumor suppressors demonstrated synergistic effect on growth inhibition and apoptosis activation. In this study, we investigated their therapeutic potential in hepatocellular carcinoma (HCC) cells. Recombinant adenoviruses co-expressing ING4 and PTEN (Ad-ING4-PTEN) were constructed, and the antitumor effect on SMMC-7721 and HepG2 HCC cells was evaluated. Ad-ING4-PTEN cooperatively inhibited cell growth, stimulated apoptosis, and suppressed invasion in both HCC cells, and regulated cell cycle in SMMC-7721. Further studies showed that the combination of ING4 and PTEN by Ad-ING4-PTEN cooperatively enhanced the alteration of the expression of cell cycle-related proteins (p53, p21, and cyclin D1) and apoptotic factors (Bad, Bcl-2, Bcl-XL, and Bax), which are involved in the regulation of cell cycle and the activation of apoptotic pathways, leading to the synergistic antitumor effect. These results indicate that the combination of ING4 and PTEN may provide an effective therapeutic strategy for HCC.

The viral oncoprotein HBx of Hepatitis B virus promotes the growth of hepatocellular carcinoma through cooperating with the cellular oncoprotein RMP.

The smallest gene HBx of Hepatitis B virus (HBV) is recognized as an important viral oncogene (V-oncogene) in the hepatocarcinogenesis. Our previous work demonstrated that RMP is a cellular oncogene (C-oncogene) required for the proliferation of hepatocellular carcinoma (HCC) cells. Here we presented the collaboration between V-oncogene HBx and C-oncogene RMP in the development of HCC. The coexpression of HBx and RMP resulted in the cooperative effect of antiapoptosis and proliferation of HCC cells. In vivo, overexpression of RMP accelerated the growth of HBx-induced xenograft tumors in nude mice and vice versa HBx promoted the growth of RMP-driven xenograft tumors. Although HBx didn't regulate the expression of RMP, HBx and RMP interact with each other and collocalized in the cytoplasm of HCC cells. HBx and RMP collaboratively inhibited the expression of apoptotic factors and promoted the expression of antiapoptotic factors. This finding suggests that HBV may induce, or at least partially contributes to the carcinogenesis of HCC, through its V-oncoprotein HBx interacting with the C-oncoprotein RMP.

Establishment of a Weight Management Scale for Patients with Congestive Heart Failure.

PURPOSE: The aim of this study was to develop a rating scale for the weight management of patients with congestive heart failure (CHF). METHODS: The original pool of items was created through in-depth interviews and a literature review. Scale validity was analyzed based on face validity, content validity, and structure validity. The content validity and structure validity were evaluated. The overall internal consistency reliability were assessed by using Cronbach's alpha and retest reliability test. RESULTS: A total of 190 CHF patients were enrolled but 5 refused. The original 19 items were then refined to a scale of 16 items. The final scale included four factors (weight monitoring, knowledge, confidence, and behaviours related to weight management), which accounted for 58.7% of the variance. Content validity ratio on the content validity was 0.88. The Cronbach's alpha was 0.843 and the retest reliability was 0.833. CONCLUSIONS: The Chinese CHF-related weight management scale developed has high reliability and validity. KEY WORDS: Congestive heart failure; Reliability; Scale; Validity; Weight management.

[Biological function and molecular mechanism of URI in HepG2 cells].

OBJECTIVE: To explore the effect and molecular mechanism of the unconventional prefoldin RPB5 interactor (URI) in hepatocellular carcinoma HepG2 cells. METHODS: The cDNA sequence and shRNA of URI were obtained and sub-cloned into eukaryotic expression vectors. Then those vectors were transfected into HepG2 cells to obtain stable transfection cell line. The cell proliferation and anchor-independent growth in URI-overexpressing and knockdown HepG2 cells were determined by CCK-8 and soft agar colony assay. Flow cytometry was applied to detect the cell cycle and apoptosis of γ-ray irradiated cells. Apoptosis related genes were detected by Western blot. RESULTS: The pCDNA3.1-URI and pGPU6-URIi eukaryotic expression vectors were constructed successfully and corresponding stable transfection cell lines were obtained. Cell proliferation rates of the HepG2, pCDNA3.1-URI-HepG2 and pGPU6-URIi-HepG2 cells were (588.78 ± 32.12)%, (959.33 ± 58.8)% and (393.93 ± 39.7)%, respectively (P < 0.05). The number of cell clones of HepG2, pCDNA3.1-URI-HepG2 and pGPU6-URIi-HepG2 cells were 43 ± 7, 85 ± 5 and 20 ± 4 (P < 0.05), respectively. After γ-ray irradiation, the URI-overexpressing cell line showed a significantly lower apoptosis rate and G(2)/M phase arrest than those in the URI-depleted cell line (P < 0.05). In the HepG2 cells, the relative protein expression levels of URI, Bax and Bcl-2 were 0.92 ± 0.03, 1.11 ± 0.13 and 0.82 ± 0.01 (P < 0.05). In the pCDNA3.1-URI-HepG2 cells, the relative protein expression levels of URI, Bax and Bcl-2 were 1.79 ± 0.12, 0.48 ± 0.01 and 2.20 ± 0.30 (P < 0.05), respectively. In the pGPU6-URIi-HepG2 cells, the relative protein expression levels of URI, Bax and Bcl-2 were 0.50 ± 0.04, 1.52 ± 0.20 and 0.38 ± 0.01 (P < 0.05), respectively. The expression of Bax was down-regulated and Bcl-2 was up-regulated in the URI-overexpressing cell line. However, on the contrary, expression of Bax was up-regulated and Bcl-2 was down-regulated in the URI-depleted cell line. CONCLUSIONS: URI may promote the growth of hepatocellular carcinoma cells via inhibition of cell proliferation and reducing the apoptosis in hepatocellular carcinoma cells in vitro. After the impairment of URI expression, the proliferation ability of hepatocellular carcinoma cells is suppressed and the ability to resist γ-ray irradiation is reduced. URI may become a potential new target for cancer therapy of hepatocellular carcinoma.

RMP plays distinct roles in the proliferation of hepatocellular carcinoma cells and normal hepatic cells.

RMP has been shown to function in the transcription regulation through association with RNA polymerase (RNAP) II subunit RPB5. It also has been shown to be required for the proliferation of hepatocellular carcinoma (HCC) cells with an antiapoptotic property. In this article, we further demonstrate that RMP displays distinct features in HCC cells compared with normal hepatic cells. RMP expression is remarkably increased in various cancer cell lines including HCC cells when compared with normal cells. Depletion of RMP could inhibit the proliferation of HCC cells, but not the normal hepatic cells. RMP significantly prevented apoptosis of HCC cells in SMMC-7721 and HepG2, but had little effect on apoptosis in the normal hepatic cells. The mechanisms of RMP's distinct features rely on different responsive expressions of apoptosis factors induced by RMP in HCC and hepatic cells. Either overexpression or depletion of RMP significantly affected the expression of apoptosis factors in HCC cells. However, normal hepatic cells showed a tendency to resist RMP for the regulation of apoptosis. In the clinical samples, the increased expression of RMP in HCCs was also observed when compared with the matched non-tumor tissues from 30 HCC patients. The different expression levels of and distinct responses to RMP between HCC and hepatic cells suggest that RMP might serve as not only a biomarker for the diagnosis of HCC, but also a potential target for the HCC therapy.

Upregulation of URI/RMP gene expression in cervical cancer by high-throughput tissue microarray analysis.

URI, or RMP, is a RNA polymerase II subunit RPB5-associated protein known to play essential roles in ubiquitination and transcription. Recently, we and others have shown that URI/RMP is also important for progression of hepatocellular carcinoma, ovarian, and prostate cancers. To identify the mechanistic basis of URI/RMP during multiple cellular processes, we investigated URI/RMP expression in a tissue microarray (TMA) containing multiple normal human tissues. The results showed that URI/RMP is ubiquitously but differentially expressed in these human tissues which partially explains its multiple cellular functions. To elucidate the role of URI/RMP during oncogenesis of multiple malignancies, especially the tumors of reproductive system, we analyzed URI/RMP expression in a TMA containing multiple reproductive system tumors. We did not observe significant difference of URI/RMP expression between cancerous and adjacent tissues of the prostate, breast, ovarian, and endometrial cancers. However, increased URI/RMP expression was observed in two of the three cases of cervical SCC (squamous cell carcinoma) cells compared to their adjacent epithelial cells. Moreover, we detected significantly upregulated URI/RMP expression not only in cervical cancers but also in pre-cancerous CINs (cervical intra-epithelial neoplasias) in a TMA that covers the whole spectrum of normal cervix, CINs, and cervical cancers. No difference of URI/RMP expression was observed between CINs and cervical cancers. Given the high risk of CINs (especially CIN3) turning into cervical cancer if left untreated, the increased URI/RMP expression in CINs as well as in cervical cancers suggest a clinical relevance of URI/RMP upon cervical cancer tumorigenesis and worth further investigation.

Effects of cell surface α2-3 sialic acid on osteogenesis.

A cell culture model of osteoblast differentiation was applied in our study of the effect of sialic acid on the osteogenesis by using the pre-osteoblast of MC3T3-E1 subclone 14 cells. Following the treatment of different concentrations of α2,3-neuraminidase, which specifically removed the α2-3 sialic acid from cell surface, a significant decrease of α2-3 sialic acid was detected with fluorescein isothiocyanate (FITC)-labeled Maackia amurensis lectin (MAL-II) by flow cytometry analysis. von Kossa staining showed that the bone mineralization decreased in MC3T3-E1 subclone 14 cells after the treatment of α2,3-neuraminidase for 2 weeks. However α2,3-neuraminidase did not affect the formation of osteoblasts in MC3T3-E1 subclone 14 cells, which was demonstrated by positive alkaline phosphatase (ALP)-staining. Characteristic biological markers and osteoblast-like cell-related factors of osteoblastic cells were also examined. Both RT-PCR and Western blot analysis demonstrated that the expression of bone sialoprotein (BSP), osteoprotegerin (OPG), and vitamin D receptor (VDR) were significantly decreased when α2-3 sialic acid expression decreased on the cell surface, while the expression of osteocalcin (OC) and osteopontin (OPN) remained unchanged. We propose a hypothesis that α2-3 sialic acid affects bone mineralization but not osteogenic differentiation.

Fcp1 dephosphorylation of the RNA polymerase II C-terminal domain is required for efficient transcription of heat shock genes.

Fcp1 dephosphorylates the C-terminal domain of the largest subunit of RNA polymerase II (Pol II) to recycle it into a form that can initiate a new round of transcription. Previously, we identified Drosophila Fcp1 as an important factor in optimal Hsp70 mRNA accumulation after heat shock. Here, we examine the role of Fcp1 in transcription of heat shock genes in vivo. We demonstrate that Fcp1 localizes to active sites of transcription including the induced Hsp70 gene. The reduced Hsp70 mRNA accumulation seen by RNA interference (RNAi) depletion of Fcp1 in S2 cells is a result of a loss of Pol II in the coding region of highly transcribed heat shock-induced genes: Hsp70, Hsp26, and Hsp83. Moreover, Fcp1 depletion dramatically increases phosphorylation of the non-chromatin-bound Pol II. Reexpression of either wild-type or catalytically dead versions of Fcp1 demonstrates that both the reduced Pol II levels on heat shock genes and the increased levels of phosphorylated free Pol II are dependent on the catalytic activity of Fcp1. Our results indicate that Fcp1 is required to maintain the pool of initiation-competent unphosphorylated Pol II, and this function is particularly important for the highly transcribed heat shock genes.