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1.  The other side of the coin 
Cell Cycle  2014;13(11):1677-1693.
Although cancer-regulatory genes are dichotomized to oncogenes and tumor-suppressor gene s, in reality they can be oncogenic in one situation but tumor-suppressive in another. This dual-function nature, which sometimes hampers our understanding of tumor biology, has several manifestations: (1) Most canonically defined genes have multiple mRNAs, regulatory RNAs, protein isoforms, and posttranslational modifications; (2) Genes may interact at different levels, such as by forming chimeric RNAs or by forming different protein complexes; (3) Increased levels of tumor-suppressive genes in normal cells drive proliferation of cancer progenitor cells in the same organ or tissue by imposing compensatory proliferation pressure, which presents the dual-function nature as a cell–cell interaction. All these manifestations of dual functions can find examples in the genes along the CCND–CDK4/6–RB axis. The dual-function nature also underlies the heterogeneity of cancer cells. Gene-targeting chemotherapies, including that targets CDK4, are effective to some cancer cells but in the meantime may promote growth or progression of some others in the same patient. Redefining “gene” by considering each mRNA, regulatory RNA, protein isoform, and posttranslational modification from the same genomic locus as a “gene” may help in better understanding tumor biology and better selecting targets for different sub-populations of cancer cells in individual patients for personalized therapy.
PMCID: PMC4111714  PMID: 24799665
CDK4; cyclin D1; oncogenes; tumor-suppressor gene s; targeted chemotherapy; radiation therapy
2.  Inhibition of Dopamine Signaling Suppresses cGMP Accumulation in rd1 Retinal Organ Cultures 
Neuroreport  2014;25(8):601-606.
The rd1 mouse is a model of retinitis pigmentosa, an inherited photoreceptor neurodegenerative disease. In rd1 retina, early onset rod degeneration is caused by a Pde6b mutation that leads to high levels of intracellular cyclic guanosine monophosphate (cGMP). Cyclic nucleotide gated ion channels (CNGCs), necessary for phototransduction, are regulated by cGMP. We previously demonstrated that inhibition of dopamine signaling blocks rd1 photoreceptor degeneration in retinal organ cultures. The mechanism underlying this protection remains unknown. The aim of this study was to determine whether inhibition of dopamine signaling alters cGMP accumulation or CNGC expression. Dopamine depletion from rd1 retinal organ cultures resulted in a significant decrease in cGMP compared to untreated rd1 organ cultures. However, cGMP levels in both treated and untreated rd1 organ cultures significantly exceeded cGMP levels in wild type (wt) retinal organ cultures. The CNGC expression profile was first determined in vivo. Both channel subunits, Cnga1 and Cngb1, are expressed at low levels by postnatal day 2 (P2), increasing sharply by P6 with modest increases after P12 in wt retina. A similar pattern is seen in rd1 retina until P12 when expression levels decrease, accompanying cell death. No significant difference was observed in the expression of either Cnga1 or Cngb1 in organ cultures from wt, rd1, or dopamine-depleted rd1 retinas. Our results demonstrate that dopamine depletion significantly decreases cGMP levels in rd1 retinal organ cultures, but that cGMP accumulation remains high, requiring additional mechanisms for photoreceptor protection. These mechanisms may include activation of PKG signaling pathways and/or crosstalk with dopamine signaling through cAMP pathways.
PMCID: PMC4275426  PMID: 24614363
retina; dopamine; retinal degeneration; rd1; cGMP; cyclic nucleotide gated channel; photoreceptor development
3.  Dorsal Raphe Neurons Signal Reward through 5-HT and Glutamate 
Neuron  2014;81(6):1360-1374.
The dorsal raphe nucleus (DRN) in the midbrain is a key center for serotonin (5-hydroxytryptamine; 5-HT) expressing neurons. Serotonergic neurons in the DRN have been theorized to encode punishment by opposing the reward signaling of dopamine neurons. Here, we show that DRN neurons encode reward, but not punishment, through 5-HT and glutamate. Optogenetic stimulation of DRN Pet-1 neurons reinforces mice to explore the stimulation-coupled spatial region, shifts sucrose preference, drives optical self-stimulation, and directs sensory discrimination learning. DRN Pet-1 neurons increase their firing activity during reward tasks and this activation can be used to rapidly change neuronal activity patterns in the cortnassociated with 5-HT, they also release glutamate, and both neurotransmitters contribute to reward signaling. These experiments demonstrate the ability of DRN neurons to organize reward behaviors and might provide insights into the underlying mechanisms of learning facilitation and anhedonia treatment.
PMCID: PMC4411946  PMID: 24656254
reward; learning; 5-HT; glutamate; Vglut3; optogenetics; brain-machine interface; tetrode recording
5.  Oxaliplatin and 5-fluorouracil hepatic infusion with lipiodolized chemoembolization in large hepatocellular carcinoma 
AIM: To investigate transarterial chemoembolization (TACE) with hepatic infusion of oxaliplatin and 5-fluorouracil and Lipiodol chemoembolization in large hepatocellular carcinoma (HCC).
METHODS: In this retrospective study, 132 patients with unresectable HCCs larger than 10 cm were treated with hepatic infusion of oxaliplatin and 5-fluorouracil followed by Lipiodol chemoembolization. The primary endpoint was overall survival (OS). Sixteen-week disease-control rate, time to progression (TTP), and major complications were also studied. Univariate and multivariate analyses were performed to identify prognostic factors affecting OS and TTP.
RESULTS: A total of 319 procedures were performed in the 132 patients. Eleven (8.3%) patients received radical resection following TACE treatment (median time to initial TACE 4.3 ± 2.3 mo). The median OS and TTP were 10.3 and 3.0 mo respectively, with a 50.0% 16-wk disease-control rate. Major complications were encountered in 6.0% (8/132) of patients following TACE and included serious jaundice in 1.5% (2/132) patients, aleukia in 1.5% (2/132), and hepatic failure in 3.0% (4/132). One patient died within one month due to serious hepatic failure and severe sepsis after receiving the second TACE. The risk factor associated with TTP was baseline alpha-fetoprotein level, and vascular invasion was an independent factor related to OS.
CONCLUSION: Hepatic infusion of oxaliplatin and 5-fluorouracil followed by lipiodolized-chemoembolization is a safe and promising treatment for patients with HCCs larger than 10 cm in diameter.
PMCID: PMC4385545  PMID: 25852283
Hepatic infusion; Large hepatocellular carcinoma; Oxaliplatin; Transarterial chemoembolization; 5-fluorouracil
6.  Polysaccharides from Medicinal Herbs As Potential Therapeutics for Aging and Age-Related Neurodegeneration 
Rejuvenation Research  2014;17(2):201-204.
Recent studies have uncovered important aging clues, including free radicals, inflammation, telomeres, and life span pathways. Strategies to regulate aging-associated signaling pathways are expected to be effective in the delay and prevention of age-related disorders. For example, herbal polysaccharides with considerable anti-oxidant and anti-inflammation capacities have been shown to be beneficial in aging and age-related neurodegenerative diseases. Polysaccharides capable of reducing cellular senescence and modulating life span via telomere and insulin pathways have also been found to have the potential to inhibit protein aggregation and aggregation-associated neurodegeneration. Here we present the current status of polysaccharides in anti-aging and anti-neurodegenerative studies.
PMCID: PMC3995358  PMID: 24125569
7.  Caenorhabditis elegans in Chinese Medicinal Studies: Making the Case for Aging and Neurodegeneration 
Rejuvenation Research  2014;17(2):205-208.
Aging is a progressive process with degenerative changes of various tissues and organs. As a classic model organism in genetics and neurobiology, Caenorhabditis elegans is also a powerful system in aging and behavioral studies and can be used at both the molecular and organismal levels to evaluate potential therapeutics for age-related neurodegeneration, owing to its short life span, relative simplicity, and high degree of experimental tractability as well as significant conservation of disease genes and signaling pathways with humans. We attempt here to summarize the use of C. elegans models in exploring traditional Chinese medicine for potential remedies against aging and neurodegeneration.
PMCID: PMC3995508  PMID: 24125529
8.  A Lower pH Value Benefits Regeneration of Trichosanthes kirilowii by Somatic Embryogenesis, Involving Rhizoid Tubers (RTBs), a Novel Structure 
Scientific Reports  2015;5:8823.
A new approach was established for the regeneration of Trichosanthes kirilowii from root, stem, and leaf explants by somatic embryogenesis (SE), involving a previously unreported SE structure, rhizoid tubers (RTBs). During SE, special rhizoids were first induced from root, stem, and leaf explants with average rhizoid numbers of 62.33, 40.17, and 11.53 per explant, respectively, on Murashige and Skoog (MS) medium (pH 4.0) supplemented with 1.0 mg/L 1-naphthaleneacetic acid (NAA) under dark conditions. Further, one RTB was formed from each of the rhizoids on MS medium (pH 4.0) supplemented with 20 mg/L thidiazuron (TDZ) under light conditions. In the suitable range (pH 4.0–9.0), a lower pH value increased the induction of rhizoids and RTBs. Approximately 37.77, 33.47, and 31.07% of in vivo RTBs from root, stem, and leaf explants, respectively, spontaneously developed into multiple plantlets on the same MS medium (supplemented with 20 mg/L TDZ) for induction of RTBs, whereas >95.00% of in vitro RTBs from each kind of explant developed into multiple plantlets on MS medium supplemented with 5.0 mg/L 6-benzylaminopurine (BAP). Morphological and histological analyses revealed that RTB is a novel type of SE structure that develops from the cortex cells of rhizoids.
PMCID: PMC4351558  PMID: 25744384
9.  Constitutive activation of NF-κB signaling by NOTCH1 mutations in chronic lymphocytic leukemia 
Oncology Reports  2015;33(4):1609-1614.
NOTCH1 mutations occur in approximately 10% of patients with chronic lymphocytic leukemia (CLL). However, the relationship between the genetic aberrations and tumor cell drug resistance or disease progression remains unclear. Frameshift deletions were detected by gene sequencing in the NOTCH1 PEST domain in three naive CLL patients. These mutations were associated with chromosomal abnormalities including trisomy 12 or 13q deletion. Of note, one of the patients developed Richter’s transformation during FCR treatment. Immunofluorescent and western blot analyses revealed a markedly higher intracellular domain of NOTCH (ICN) expression in the mutated cells compared with their unmutated counterparts and normal CD19+ B lymphocytes (P<0.01 and P<0.001, respectively). In addition, strong DNA-κB binding activities were observed in the mutant cells by gel shift assays. RT-PCR analysis revealed elevated RelA mRNA expression in the mutant cells, while RelB levels were variable. Reduced levels of RelA and RelB mRNA were observed in unmutated CLL and normal B cells. Compared to unmutated CLL and normal B cells, increased apoptosis occurred in the mutant cells in the presence of GSI (ICN inhibitor) and PDTC (NF-κB inhibitor), particularly under the synergistic effects of the two drugs (P=0.03). Moreover, IKKα and IKKβ, the active components in the NF-κB pathway, were markedly inhibited following prolonged treatment with GSI and PDTC. These results suggested that NOTCH1 mutations constitutively activate the NF-κB signaling pathway in CLL, which is likely related to ICN overexpression, indicating NOTCH1 and NF-κB as potential therapeutic targets in the treatment of CLL.
PMCID: PMC4358086  PMID: 25633905
chronic lymphocytic leukemia; NF-κB; NOTCH1
10.  Blockage of tropomyosin receptor kinase a (TrkA) enhances chemo-sensitivity in breast cancer cells and inhibits metastasis in vivo 
Hyper-activation of the Neurotrophin Receptor Signaling contributes to the development and metastasis of breast cancer. The inhibition of growth factor-dependent growth of breast cancer cell demonstrated a promising way for cancer therapy. In this study, the signaling pathway of tropomyosin receptor kinase A (TrkA) had been investigated for the role it played in the proliferation of chemo-resistance of breast cancer cells. Small interference RNA (siRNA) was used to down-regulate the expression of TrkA in breast cancer cell and tumor xenograft mice model. Our results indicated that siRNA mediated down-regulation of TrkA lead to the proliferation inhibition of cancer cells and arrested cells cycle at G0/G1 phase via inactivation of NF-κBp65. Application of TrkA siRNA to cancer cell also increased the chemo-sensitivity to paclitaxel, and further promoted apoptosis in cancer cell through the activation of caspase-3. Moreover, TrkA siRNA increased the efficacy of paclitaxel and decreased the incidence of lung metastasis in tumor xenografted mice. In sum, these results indicate that TrkA signaling plays an important role in breast cancer chemo-resistance and metastasis. It could be a potential pharmacologic target to enhance the effectiveness of chemo-therapy for breast cancer.
PMCID: PMC4358493  PMID: 25785038
TrkA; siRNA; breast cancer; metastasis
11.  Transcriptome analysis of the compatible interaction of tomato with Verticillium dahliae using RNA-sequencing 
Tomato Verticillium wilt is a soil-borne vascular disease caused by the necrotrophic fungus Verticillium dahliae. Although some understanding of plant defense mechanisms against V. dahliae infection has been gained for incompatible interactions, including identification of inducible resistant genes and defense signaling pathways, the genes and signaling pathways involved in the compatible interaction remain unclear. To investigate the molecular basis of the compatible interaction between tomato and V. dahliae, transcriptomes of V. dahliae infected tomatoes were compared to those of a control group. A total of approximately 25 million high-quality reads were generated by means of the RNA sequencing (RNA-seq) method. The sequence reads were aligned to the tomato reference genome and analyzed to measure gene expression levels, and to identify alternative splicing events. Comparative analysis between the two samples revealed 1,953 significantly differentially expressed genes (DEGs), including 1,281 up-regulated and 672 down-regulated genes. The RNA-Seq output was confirmed using RT-qPCR for 10 selected genes. The Nr, Swiss-Prot, Gene Ontology (GO), Clusters of Orthologous Groups (COG), and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases were used to annotate DEG functions. Of the 1,953 DEGs identified, 1,953, 1,579, 1,739, 862, and 380 were assigned by Nr, Swiss-Prot, GO, COG, and KEGG, respectively. The important functional groups identified via GO and COG enrichment were those responsible for fundamental biological regulation, secondary metabolism, and signal transduction. Of DEGs assigned to 87 KEGG pathways, most were associated with phenylpropanoid metabolism and plant–pathogen interaction pathways. Most of the DEGs involved in these two pathways were up-regulated, and may be involved in regulating the tomato-V. dahliae compatible interaction. The results will help to identify key susceptible genes and contribute to a better understanding of the mechanisms of tomato susceptible response to V. dahliae.
PMCID: PMC4458571  PMID: 26106404
tomato; Verticillium dahliae; compatible interaction; RNA sequencing; transcriptome analysis
12.  Just like the rest of evolution in Mother Nature, the evolution of cancers may be driven by natural selection, and not by haphazard mutations 
Oncoscience  2014;1(9):580-590.
Sporadic carcinogenesis starts from immortalization of a differentiated somatic cell or an organ-specific stem cell. The immortalized cell incepts a new or quasinew organism that lives like a parasite in the patient and usually proceeds to progressive simplification, constantly engendering intermediate organisms that are simpler than normal cells. Like organismal evolution in Mother Nature, this cellular simplification is a process of Darwinian selection of those mutations with growth- or survival-advantages, from numerous ones that occur randomly and stochastically. Therefore, functional gain of growth- or survival-sustaining oncogenes and functional loss of differentiation-sustaining tumor suppressor genes, which are hallmarks of cancer cells and contribute to phenotypes of greater malignancy, are not drivers of carcinogenesis but are results from natural selection of advantageous mutations. Besides this mutation-load dependent survival mechanism that is evolutionarily low and of an asexual nature, cancer cells may also use cell fusion for survival, which is an evolutionarily-higher mechanism and is of a sexual nature. Assigning oncogenes or tumor suppressor genes or their mutants as drivers to induce cancer in animals may somewhat coerce them to create man-made oncogenic pathways that may not really be a course of sporadic cancer formations in the human.
PMCID: PMC4278337  PMID: 25594068
evolution; cancer; oncogenes; tumor suppressor genes; mutation
13.  Necrosis, and then stress induced necrosis-like cell death, but not apoptosis, should be the preferred cell death mode for chemotherapy: clearance of a few misconceptions 
Oncoscience  2014;1(6):407-422.
Cell death overarches carcinogenesis and is a center of cancer researches, especially therapy studies. There have been many nomenclatures on cell death, but only three cell death modes are genuine, i.e. apoptosis, necrosis and stress-induced cell death (SICD). Like apoptosis, SICD is programmed. Like necrosis, SICD is a pathological event and may trigger regeneration and scar formation. Therefore, SICD has subtypes of stress-induced apoptosis-like cell death (SIaLCD) and stress-induced necrosis-like cell death (SInLCD). Whereas apoptosis removes redundant but healthy cells, SICD removes useful but ill or damaged cells. Many studies on cell death involve cancer tissues that resemble parasites in the host patients, which is a complicated system as it involves immune clearance of the alien cancer cells by the host. Cancer resembles an evolutionarily lower-level organism having a weaker apoptosis potential and poorer DNA repair mechanisms. Hence, targeting apoptosis for cancer therapy, i.e. killing via SIaLCD, will be less efficacious and more toxic. On the other hand, necrosis of cancer cells releases cellular debris and components to stimulate immune function, thus counteracting therapy-caused immune suppression and making necrosis better than SIaLCD for chemo drug development.
PMCID: PMC4284620  PMID: 25594039
Apoptosis; Cancer therapy; Carcinogenesis; Evolution; Hyperthermia
14.  Regeneration of Solanum nigrum by Somatic Embryogenesis, Involving Frog Egg-Like Body, a Novel Structure 
PLoS ONE  2014;9(6):e98672.
A new protocol was established for the regeneration of Solanum nigrum by frog egg-like bodies (FELBs), which are novel somatic embryogenesis (SE) structures induced from the root, stem, and leaf explants. The root, stem, and leaf explants (93.33%, 85.10%, and 100.00%, respectively) were induced to form special embryonic calli on Murashige and Skoog (MS) medium containing 1.0 mg/L 2,4-dichlorophenoxyacetic acid, under dark condition. Further, special embryonic calli from the root, stem, and leaf explants (86.97%, 83.30%, and 99.47%, respectively) were developed into FELBs. Plantlets of FELBs from the three explants were induced in vitro on MS medium supplemented with 5.0 mg/L 6-benzylaminopurine and 0.1 mg/L gibberellic acid, and 100.00% plantlet induction rates were noted. However, plantlet induction in vivo on MS medium supplemented with 20 mg/L thidiazuron showed rates of 38.63%, 15.63%, and 61.30% for the root, stem, and leaf explants, respectively, which were lower than those of the in vitro culture. Morphological and histological analyses of FELBs at different development stages revealed that they are a novel type of SE structure that developed from the mesophyll (leaf) or cortex (stem and root) cells of S. nigrum.
PMCID: PMC4045584  PMID: 24896090
15.  Maintenance of Stemness in Oxaliplatin-Resistant Hepatocellular Carcinoma Is Associated with Increased Autocrine of IGF1 
PLoS ONE  2014;9(3):e89686.
Evidence suggests that many types of cancers are composed of different cell types, including cancer stem cells (CSCs). We have previously shown that the chemotherapeutic agent oxaliplatin induced epithelial-mesenchymal transition, which is thought to be an important mechanism for generating CSCs. In the present study, we investigate whether oxaliplatin-treated cancer tissues possess characteristics of CSCs, and explore oxaliplatin resistance in these tissues.
Hepatocellular carcinoma cells (MHCC97H cells) were subcutaneously injected into mice to form tumors, and the mice were intravenously treated with either oxaliplatin or glucose. Five weeks later, the tumors were orthotopically xenografted into livers of other mice, and these mice were treated with either oxaliplatin or glucose. Metastatic potential, sensitivity to oxaliplatin, and expression of CSC-related markers in the xenografted tumor tissues were evaluated. DNA microarrays were used to measure changes in gene expression as a result of oxaliplatin treatment. Additionally, an oxaliplatin-resistant cell line (MHCC97H-OXA) was established to assess insulin-like growth factor 1 secretion, cell invasion, cell colony formation, oxaliplatin sensitivity, and expression of CSC-related markers. The effects of an insulin-like growth factor 1 receptor inhibitor were also assessed.
Oxaliplatin treatment inhibited subcutaneous tumor growth. Tumors from oxaliplatin-treated mice that were subsequently xenografted into livers of other mice exhibited that decreasing sensitivity to oxaliplatin and increasing pulmonary metastatic potential. Among the expression of CSC-related proteins, the gene for insulin-like growth factor 1, was up-regulated expecially in these tumor tissues. Additionally, MHCC97H-OXA cells demonstrated that increasing cell invasion, colony formation, and expression of insulin-like growth factor 1 and CSC-related markers, whereas treatment with an inhibitor of the insulin-like growth factor 1 receptor suppressed these effects.
Maintenance of stemness in oxaliplatin-resistant hepatocellular carcinoma cells is associated with increased autocrine of IGF1.
PMCID: PMC3954560  PMID: 24632571
16.  Radiofrequency ablation following first-line transarterial chemoembolization for patients with unresectable hepatocellular carcinoma beyond the Milan criteria 
BMC Gastroenterology  2014;14:11.
Recent studies suggest that a combination of radiofrequency ablation (RFA) and transarterial chemoembolization (TACE) may have theoretical advantages over TACE alone for treatment of hepatocellular carcinoma (HCC). The purpose of this study was to evaluate the effectiveness and safety of radiofrequency ablation following first-line TACE treatment in the management of HCC beyond the Milan Criteria.
Forty-five patients who consecutively underwent RFA following first-line TACE treatment for HCC beyond the Milan criteria were enrolled in this study. RFA was performed within 1–2 months after TACE treatment in patients who had incomplete necrotic tumor nodules. Primary effectiveness, complications, survival rates, and prognostic factors were evaluated retrospectively.
Complete ablation was achieved in 76.2% of the lesions according to 1-month follow-up computed tomography/magnetic resonance imaging evaluation. The mean follow-up period was 30.9 months (range 3–94 months). There were no major complications after RFA therapy. The median overall survival was 29 months (range 20–38 months), with 1-, 2-, and 3-year survival of 89%, 61%, and 43%, respectively. Multivariate analysis revealed that tumor diameter (P = 0.045, hazard ratio [HR] = 0.228, 95% confidence interval [CI]: 0.054-0.968) and pretreatment serum alpha-fetoprotein level (P = 0.024, HR = 2.239, 95% CI: 1.114-4.500) were independent predictors for long-term survival.
HCC beyond the Milan criteria can be completely and safely ablated by radiofrequency ablation following first-line TACE treatment with a low rate of complications and favorable survival outcome. Further assessment of the survival benefits of combination treatment for HCCs beyond the Milan Criteria is warranted.
PMCID: PMC3890612  PMID: 24410841
Hepatocellular carcinoma; Radiofrequency ablation; Transcatheter arterial chemoembolization; Milan criteria
17.  A Rapid, Highly Efficient and Economical Method of Agrobacterium-Mediated In planta Transient Transformation in Living Onion Epidermis 
PLoS ONE  2014;9(1):e83556.
Transient transformation is simpler, more efficient and economical in analyzing protein subcellular localization than stable transformation. Fluorescent fusion proteins were often used in transient transformation to follow the in vivo behavior of proteins. Onion epidermis, which has large, living and transparent cells in a monolayer, is suitable to visualize fluorescent fusion proteins. The often used transient transformation methods included particle bombardment, protoplast transfection and Agrobacterium-mediated transformation. Particle bombardment in onion epidermis was successfully established, however, it was expensive, biolistic equipment dependent and with low transformation efficiency. We developed a highly efficient in planta transient transformation method in onion epidermis by using a special agroinfiltration method, which could be fulfilled within 5 days from the pretreatment of onion bulb to the best time-point for analyzing gene expression. The transformation conditions were optimized to achieve 43.87% transformation efficiency in living onion epidermis. The developed method has advantages in cost, time-consuming, equipment dependency and transformation efficiency in contrast with those methods of particle bombardment in onion epidermal cells, protoplast transfection and Agrobacterium-mediated transient transformation in leaf epidermal cells of other plants. It will facilitate the analysis of protein subcellular localization on a large scale.
PMCID: PMC3885512  PMID: 24416168
18.  The Study on Biocompatibility of Porous nHA/PLGA Composite Scaffolds for Tissue Engineering with Rabbit Chondrocytes In Vitro 
BioMed Research International  2013;2013:412745.
Objective. To examine the biocompatibility of a novel nanohydroxyapatite/poly[lactic-co-glycolic acid] (nHA/PLGA) composite and evaluate its feasibility as a scaffold for cartilage tissue engineering. Methods. Chondrocytes of fetal rabbit were cultured with nHA/PLGA scaffold in vitro and the cell viability was assessed by MTT assay first. Cells adhering to nHA/PLGA scaffold were then observed by inverted microscope and scanning electron microscope (SEM). The cell cycle profile was analyzed by flow cytometry. Results. The viability of the chondrocytes on the scaffold was not affected by nHA/PLGA comparing with the control group as it was shown by MTT assay. Cells on the surface and in the pores of the scaffold increased in a time-dependent manner. Results obtained from flow cytometry showed that there was no significant difference in cell cycle profiles between the coculture group and control (P > 0.05). Conclusion. The porous nHA/PLGA composite scaffold is a biocompatible and good kind of scaffold for cartilage tissue engineering.
PMCID: PMC3860085  PMID: 24380082
19.  The miRNA let-7a1 inhibits the expression of insulin-like growth factor 1 receptor (IGF1R) in prostate cancer PC-3 cells 
Asian Journal of Andrology  2013;15(6):753-758.
Reduced microRNA (miRNA) let-7a expression and the activation of insulin-like growth factor-1 receptor (IGF1R) signalling are both involved in prostate cancer and progression. In the present study, we demonstrated that the growth inhibitory effect of let-7a1 is directly related to targeting IGF1R gene expression in PC-3 cells. TargetScan predicted three potential target sites (T1, T2 and T3) of let-7a in the 3′ untranslational region (3′ UTR) of IGF1R mRNA. Real-time PCR, Western blot and luciferase reporter assays were used to detect the effects of let-7a1 overexpression or let-7a1 inhibitor on the IGF1R gene expression in PC-3 cells. The results indicated that let-7a1 could inhibit IGF1R expression by directly targeting the T1 and T2 sites in the 3′ UTR of the IGF1R mRNA. We then used RT-PCR, luciferase reporter assays, 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyl-2H-tetrazolium bromide (MTT) assay, flow cytometry and Hoechst 33342 staining to examine whether let-7a1-mediated inhibition of IGF1R expression also affects the IGF1R-mediated signalling events, including Elk1 activity and c-fos gene expression, proliferation, apoptosis and cell cycle. We demonstrated that let-7a1-mediated IGF1R downregulation was accompanied by attenuation of Elk1 activity and c-fos expression, inhibition of cell proliferation, enhanced apoptosis and cell cycle arrest, and that loss function of let-7a1 via inhibition can upregulate IGF1R accompanied by an increase of Elk1 activity and c-fos expression, thereby enhancing cell proliferation. Altogether, these findings suggest that let-7a may be novel therapeutic candidate for prostate cancer.
PMCID: PMC3854054  PMID: 23974362
IGF1R; microRNA (miRNA); prostate cancer
20.  Palliative surgery for primary sarcoma in the abdominal aorta: A case report and review of the literature 
Oncology Letters  2013;6(6):1738-1740.
Primary sarcoma of the aorta is extremely rare and accounts for <1% of all sarcomas. The present study describes the case of a 45-year-old male who presented with lower limb and abdominal pain. Abdominal computed tomography (CT) and magnetic resonance (MR) arteriography revealed a tumor that extended from the infrarenal aorta to the aortic bifurcation. The external and internal iliac arteries were occluded by the tumor incursion. Palliative surgery was performed for the sarcoma since the patient refused a radical resection. To improve the blood supply to the lower limbs, an axillary bifemoral bypass was established. Following the surgery, the pain was significantly reduced. However, the patient succumbed due to extensive metastasis 6 months after this surgery. Aortic sarcoma is an extremely rare disease with a poor prognosis. A diagnosis at a relatively early stage is necessary for a longer survival time. Radical surgery is the most significant treatment. Patients at advanced stages should consider palliative surgery in order to improve their quality of life.
PMCID: PMC3834868  PMID: 24273607
abdominal aortic aneurysm; palliative surgery
21.  Proteolytic Characteristics of Cathepsin D Related to the Recognition and Cleavage of Its Target Proteins 
PLoS ONE  2013;8(6):e65733.
Cathepsin D (CD) plays an important role in both biological and pathological processes, although the cleavage characteristics and substrate selection of CD have yet to be fully explored. We employed liquid chromatography-tandem mass spectrometry (LC-MS/MS) to identify the CD cleavage sites in bovine serum albumin (BSA). We found that the hydrophobic residues at P1 were not only a preferential factor for CD cleavage but that the hydrophobicity at P1’ also contributed to CD recognition. The concept of hydrophobic scores of neighbors (HSN) was proposed to describe the hydrophobic microenvironment of CD recognition sites. The survey of CD cleavage characteristics in several proteins suggested that the HSN was a sensitive indicator for judging the favorable sites in peptides for CD cleavage, with HSN values of 0.5–1.0 representing a likely threshold. Ovalbumin (OVA), a protein resistant to CD cleavage in its native state, was easily cleaved by CD after denaturation, and the features of the cleaved peptides were quite similar to those found in BSA, where a higher HSN value indicated greater cleavability. We further conducted two-dimensional gel electrophoresis (2DE) to find more proteins that were insensitive to CD cleavage in CD-knockdown cells. Based on an analysis of secondary and three-dimensional structures, we postulated that intact proteins with a structure consisting of all α-helices would be relatively accessible to CD cleavage.
PMCID: PMC3688724  PMID: 23840360
22.  Quantitative Evaluation of Aldo–keto Reductase Expression in Hepatocellular Carcinoma (HCC) Cell Lines 
The involvement of aldo–keto reductases (AKRs) in tumorigenesis is widely reported, but their roles in the pathological process are not generally recognized due to inconsistent measurements of their expression. To overcome this problem, we simultaneously employed real-time PCR to examine gene expression and multiple reaction monitoring (MRM) of mass spectrometry (MS) to examine the protein expression of AKRs in five different hepatic cell lines. These include one relatively normal hepatic cell line, L-02, and four hepatocellular carcinoma (HCC) cell lines, HepG2, HuH7, BEL7402 and SMMC7721. The results of real-time PCR showed that expression of genes encoding the AKR1C family members rather than AKR1A and AKR1B was associated with tumor, and most of genes encoding AKRs were highly expressed in HuH7. Similar observations were obtained through MRM. Different from HuH7, the protein abundance of AKR1A and AKR1B was relatively consistent among the other four hepatic cell lines, while protein expression of AKR1C varied significantly compared to L-02. Therefore, we conclude that the abundant distribution of AKR1C proteins is likely to be associated with liver tumorigenesis, and the AKR expression status in HuH7 is completely different from other liver cancer cell lines. This study, for the first time, provided both overall and quantitative information regarding the expression of AKRs at both mRNA and protein levels in hepatic cell lines. Our observations put the previous use of AKRs as a biomarker into question since it is only consistent with our data from HuH7. Furthermore, the data presented herein demonstrated that quantitative evaluation and comparisons within a protein family at both mRNA and protein levels were feasible using current techniques.
PMCID: PMC4357791  PMID: 23584128
Aldo–keto reductase; HCC; Quantitative analysis; Real-time PCR; Multiple reaction monitoring
23.  The Clinical Significance of the CD163+ and CD68+ Macrophages in Patients with Hepatocellular Carcinoma 
PLoS ONE  2013;8(3):e59771.
Our previous study has found that the abundance of peritumoral CD68+ macrophages was associated with poor prognosis in hepatocellular carcinoma (HCC) after resection. However, CD68 staining could not discriminate the protumoral or tumoricidal subpopulations from pan-macrophages. CD163 is a marker of alternatively activated macrophages. In this study, the clinical significance of CD163+ cells in tumors and peritumoral liver tissues was evaluated in a cohort of 295 patients with HCC after curative resection. We found that the density of CD163+ cells was well correlated with that of CD68+ cells in both tumors and peritumoral liver tissues but was much more. Immunostaining on consecutive sections and flow cytometry assay on surgical resected specimens further supported the findings that the CD163+ cells was more abundant than CD68+ cells. The density of peritumoral CD68+ cells was associated with poor recurrence-free survival (RFS) and poor overall survival (OS) (P = 0.004 and P = 0.001, respectively), whereas the CD163+ cells have no prognostic values either in tumors or in peritumoral liver tissues. In another cohort of 107 HCC patients, preoperative plasma concentration of soluble form of CD163 (sCD163) was associated with active hepatitis-related factors but not associated with the markers of tumor invasion. In conclusion, both the CD163+ cells local infiltration and plasma sCD163 were of limited significance in HCC, and they were more likely markers related to active hepatitis rather than tumor progression.
PMCID: PMC3612077  PMID: 23555776
24.  Direct Transformation of Lung Microenvironment by Interferon-α Treatment Counteracts Growth of Lung Metastasis of Hepatocellular Carcinoma 
PLoS ONE  2013;8(3):e58913.
Interferon (IFN)-α is effective in inhibiting tumor growth and metastasis of hepatocellular carcinoma (HCC). However, the biologic mechanisms of IFN-α treatment in lung metastasis are not yet clear.
The effect of IFN-α treatment was studied by using an orthotopic xenograft model and measuring tumor size and lung metastasis. Pretreatment with IFN-α before implantation of tumor was done to explore the effect of IFN-α on lung tissues. Cytokines and macrophages were measured by immunohistochemistry and/or PCR assay, using human origin or mouse origin primers to differentiate the sources. Circulating tumor cells (CTCs) were also assayed by flow cytometry.
IFN-α treatment did not decrease the number of CTCs (0.075%±0.020% versus 0.063%±0.018%, P = 0.574, IFN-α–treated versus control groups), but did decrease the number and size of lung metastasis (number: 1.75±1.0 versus 28.0±6.3, P = 0.008; size [pixels]: 116.8±72.2 versus 5226.4±1355.7, P = 0.020), and inhibited macrophage infiltration (0.20%±0.04% versus 1.36%±0.21%, P = 0.0058) and alteration of matrix metalloproteinase (MMP)-9 expression (mean integrated optical density (IOD): 5.1±1.7 versus 21.9±0.4, P<0.000) in the lung, which was independent of the primary tumor.
IFN-α inhibited lung metastasis by directly modulating the lung microenvironment.
PMCID: PMC3601095  PMID: 23527047
25.  Genetic Variations in the KCNJ5 Gene in Primary Aldosteronism Patients from Xinjiang, China 
PLoS ONE  2013;8(1):e54051.
Primary aldosteronism (PA) is the most common endocrine form of secondary hypertension, and one of the most common subtypes of sporadic PA is aldosterone-producing adenoma (APA). Recently, two somatic mutations of the KCNJ5 gene were implicated in APA, and two germline mutations were associated with familial hyperaldosteronism III.
This case-control study was designed to investigate the relationship between genetic variations in the KCNJ5 gene and sporadic PA patients in Xinjiang, China.
Five common single nucleotide polymorphisms (SNPs) of the KCNJ5 gene (rs6590357, rs4937391, rs3740835, rs2604204, and rs11221497) were detected in patients with sporadic PA (n = 235) and essential hypertension (EH; n = 913) by the TaqMan polymerase chain reaction method.
The EH group and the PA group showed significant differences in the distributions of genotypes and alleles of rs4937391 and rs2604204 in total and male subjects (P<0.05), as well as rs3740835 in male subjects (P<0.05). However, only the association between the rs2604204 genotype and male sporadic PA remained significant after Bonferroni’s correction (P<0.01). Furthermore, logistic regression analysis demonstrated that the CC genotype of rs2604204 was a risk factor for male patients with sporadic PA, after adjusting for age and body mass index (odds ratio = 2.228, 95% CI: 1.300–3.819, P = 0.004).
The genetic variant rs2604204 of KCNJ5 is associated with sporadic PA in Chinese males, suggesting that KCNJ5 may be involved in the pathogenesis of sporadic PA in these particular patients.
PMCID: PMC3561325  PMID: 23382865

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