HADHA overexpression disrupts lipid metabolism and inhibits tumor growth in clear cell renal cell carcinoma.

Hydroxyacyl-CoA dehydrogenase alpha subunit (HADHA) is a key lipid metabolic enzyme with a novel role in carcinogenesis. We previously reported that HADHA, a prognostic marker, was downregulated in clear cell renal cell carcinoma (ccRCC). Herein, the tumor inhibitory role of HADHA overexpression in ccRCC was investigated further. The quantitative proteomic analysis displayed that a total of 1293 and 1293 proteins were identified in HADHA overexpressed 786-O-hadha and vector-transfected control 786-O-vc cells, respectively, and 206 proteins were found to be up- or downregulated. PANTHER, OmicsNet, STRING, and DAVID tools were utilized on the dysregulated proteins in order to elucidate multiple metabolic pathways (especial lipid metabolism) and lipid metabolism-related proteins (e.g. ACAT1, ACLY). The dysregulation of the lipid metabolic enzymes, ACAT1, ACLY, CYB5R3 and FASN, were confirmed by Western blotting. Further assays demonstrated that HADHA overexpression significantly inhibited cell growth, induced cell apoptosis, and decreased the formation of cytoplasmic lipid droplets (LDs); moreover, it also inhibited tumor growth and lessened the formation of LDs in xenografted mouse. Collectively, these data revealed that HADHA overexpression disrupted lipid metabolism and inhibited tumor growth, which shed light on HADHA as a potential therapeutic target for clinical intervention of ccRCC.

Astragaloside IV protects ATDC5 cells from lipopolysaccharide-caused damage through regulating miR-203/MyD88.

Context: Osteoarthritis (OA) is a degenerative arthrosis sickness. Astragaloside IV (AS-IV) functions by relieving inflammatory damage.Objective: We aimed to investigate the mechanism by which AS-IV protects ATD cells from lipopolysaccharide (LPS)-induced damage.Materials and methods: ATDC5 cells were transfected with miR-203 inhibitor and NC inhibitor (150 nM) or pEX-MyD88 and sh-MyD88 (50 nM) for 48 h, pre-treated by 15 µg/mL AS-IV for 24 h, then treated by 5 µg/mL LPS for 12 h. Dual-luciferase activity testing was used to determine whether miR-203 could bind to MyD88. CCK-8 and flow cytometry were used to detect cell activity and apoptosis, respectively, and qRT-PCR, western blots, and ELISA were performed to detect expression levels of miR-203 and inflammatory cytokines.Results: Based on the 50% inhibiting concentration (IC50), there was no significant difference of AS-IV (0 to 15 µg/mL) on cell viability. Fifteen µg/mL was the optimal concentration of AS-IV in treating LPS-induced inflammatory damage in subsequent experiments since this was a semi-lethal concentration. AS-IV significantly reduces LPS-induced viability, apoptosis and the release of TNF-α, IL-6 and iNOS mainly through up-regulating miR-203. Further, MyD88 was a target gene of miR-203 and negatively regulated by miR-203. Knockdown of MyD88 inhibited LPS-induced inflammatory damage by inhibiting the NF-κB signal pathway.Discussion and conclusions: AS-IV protects ATDC5 cells against LPS-induced damage mainly via regulating miR-203/MyD88. Our results support a theoretical basis for in-depth study of the function of AS-IV and the clinical cure of OA.

p53-inducible gene 3 promotes cell migration and invasion by activating the FAK/Src pathway in lung adenocarcinoma.

The p53-inducible gene 3 (PIG3) is one of the p53-induced genes at the onset of apoptosis, which plays an important role in cell apoptosis and DNA damage response. Our previous study reported an oncogenic role of PIG3 associated with tumor progression and metastasis in non-small cell lung cancer (NSCLC). In this study, we further analyzed PIG3 mRNA expression in 504 lung adenocarcinoma (LUAD) and 501 lung squamous cell carcinoma (LUSC) tissues from The Cancer Genome Atlas database and we found that PIG3 expression was significantly higher in LUAD with lymph node metastasis than those without, while no difference was observed between samples with and without lymph node metastasis in LUSC. Gain and loss of function experiments were performed to confirm the metastatic role of PIG3 in vitro and to explore the mechanism involved in its oncogenic role in NSCLC metastasis. The results showed that PIG3 knockdown significantly inhibited the migration and invasion ability of NSCLC cells, and decreased paxillin, phospho-focal adhesion kinase (FAK) and phospho-Src kinase expression, while its overexpression resulted in the opposite effects. Blocking FAK with its inhibitor reverses PIG3 overexpression-induced cell motility in NSCLC cells, indicating that PIG3 increased cell metastasis through the FAK/Src/paxillin pathway. Furthermore, PIG3 silencing sensitized NSCLC cells to FAK inhibitor. In conclusion, our data revealed a role for PIG3 in inducing LUAD metastasis, and its role as a new FAK regulator, suggesting that it could be considered as a novel prognostic biomarker or therapeutic target in the treatment of LUAD metastasis.

The vanillin derivative 6-bromine-5-hydroxy-4-methoxybenzaldehyde induces aberrant mitotic progression and enhances radio-sensitivity accompanying suppression the expression of PLK1 in esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is the most common form of esophageal cancer in China. Since chemotherapy is the standard clinical intervention for advanced ESCC, the development of highly effective and minimal/non-toxic drugs is essential to improve the clinical outcome and prognosis of the patients. A novel derivative of vanillin, 6-bromine-5-hydroxy-4-methoxybenzaldehyde (BVAN08), has been recently reported to activate different cell death pathways in cancer cells. In this study, we demonstrate that BVAN08 exhibits a potent anti-proliferation effect on ESCC cells (TE-1 and ECA-109) by inhibiting the expression of PLK1, an important mitotic kinase. Consistent with this, BVAN08 induces mitotic arrest and chromosomal misalignment in ESCC cells. The disruption of microtubule nucleation around centrosomes is also observed in BVAN08 treated ESCC cells. Furthermore, BVAN08 enhances radio-sensitivity of ESCC cells by prolonging DNA damage repair. These findings underscore the potential value of BVAN08 in cancer therapeutics and demonstrate the underlying mechanism by which BVAN08 induces mitotic catastrophe and enhances radio-sensitivity in ESCC cells.

Silencing Livin induces apoptotic and autophagic cell death, increasing chemotherapeutic sensitivity to cisplatin of renal carcinoma cells.

Renal cell carcinoma (RCC) accounts for 3 % of all adult malignancies and is the most lethal urological cancer. Livin is a member of the inhibitor of apoptosis protein (IAP) family, which is associated with tumor resistance to radiotherapy and chemotherapy. Clinical data also showed that patients with high tumor grades and stages have higher expression levels of Livin in RCC cells. Autophagy is a survival mechanism activated in response to nutrient deprivation. A possible role of Livin in the autophagy of RCC cells has not been investigated; therefore, this pioneer study was carried out. Livin was silenced in RCC cells (slow virus infection [SVI]-shLivin cells) by lentiviral transfection. Then, mRNA and protein expression levels in the transfected cells were assessed by quantitative fluorescence PCR and Western blotting, respectively. In addition, acridine orange staining and electron microscopy were used to assess autophagy in SVI-shLivin cells. The cisplatin IC50 values for RCC cells were measured by the CCK8 assay. Potent antitumor activities were observed in xenograft mouse models generated with Livin-silenced RCC cells in terms of delayed tumor onset and suppressed tumor growth. These results suggested that Livin silencing could increase the chemotherapeutic sensitivity of RCC cells to cisplatin and induce autophagic cell death. A possible mechanism of Bcl-2 and Akt pathway involvement was discussed specifically in this study. Overall, Livin silencing induces apoptotic and autophagic cell death and increases chemotherapeutic sensitivity of RCC cells to cisplatin.

CYLD downregulates Livin and synergistically improves gemcitabine chemosensitivity and decreases migratory/invasive potential in bladder cancer: the effect is autophagy-associated.

Although GC (gemcitabine and cisplatin) chemotherapy remains an effective method for treating bladder cancer (BCa), chemoresistance is a major obstacle in chemotherapy. In this study, we determined whether gemcitabine resistance correlates with migratory/invasive potential in BCa and whether this relationship is regulated by the cylindromatosis (CYLD)-Livin module. First, we independently investigated the correlation of CYLD/Livin and gemcitabine resistance with the potential for tumor migration and invasiveness. Second, we found that co-transfected CYLD and Livin dramatically improved sensitivity to gemcitabine chemotherapy and decreased migration/invasion potential. Next, we determined that CYLD may regulate Livin by the NF-κB-dependent pathway. We also found that CYLD overexpression and Livin knockdown might improve gemcitabine chemosensitivity by decreasing autophagy and increasing apoptosis in BCa cells. Finally, the effects of CYLD-Livin on tumor growth in vivo were evaluated. Our study demonstrates that CYLD-Livin might represent a potential therapeutic for chemoresistant BCa.

Polymerase iota (POLI) confers radioresistance of esophageal squamous cell carcinoma by regulating RAD51 stability and facilitating homologous recombination.

Radiotherapy resistance is an important and urgent challenge in the clinical management of esophageal squamous carcinoma (ESCC). However, the factors mediating the ESCC resistance to radiotherapy and its underlying molecular mechanisms are not fully clarified. Our previous studies have demonstrated the critical role of DNA polymerase iota (POLI) in ESCC development and progression, here, we aimed to investigate the involvement of POLI in ESCC radiotherapy resistance and elucidate the underlying molecular mechanism. We found that highly expressed POLI was correlated with shorter overall survival of ESCC patients received radiotherapy. Down-regulation of POLI sensitized ESCC to IR, prolonged γH2AX foci in nuclei and comet tails after IR. HR but not NHEJ repair is inhibited in POLI-deficient ESCC cells. POLI stabilizes RAD51 protein via competitively binding with and blocking the interaction between RAD51 and E3 ligase XIAP and XIAP-mediated ubiquitination. Furthermore, loss of POLI leads to the activation of GAS signaling. Our findings provide novel insight into the role of POLI in the development of radioresistance mediated by stabilizing RAD51 protein in ESCC.

Ductal adenocarcinoma of the prostate or seminal vesicle adenocarcinoma: An multi-disciplinary team (MDT) case report and literature review.

We introduced a 61-year-old male with ductal adenocarcinoma of the prostate who underwent a tortuous diagnosis and treatment. Multi-disciplinary team meetings organized by our hospital have shown great value in the whole process. The patient presented with gross hematuria accompanied by frequent urination initially, and was diagnosed with ductal adenocarcinoma of the prostate involving right seminal vesicle gland and urethra by urethroscopy biopsy. The clinical stage of tumor was T3bN0M0. After 4 cycles of neoadjuvant chemotherapy, the tumor shrank significantly and the patient underwent a laparoscopic radical prostatectomy. But the patient declined to continue chemotherapy postoperatively. After 10 months, the serum prostatic specific antigen increased to 0.05 ng/mL, and multiple metastases were found in the patient's bilateral lungs. However, an unexpected diagnosis of seminal vesicle adenocarcinoma was put forward from another hospital after supplementary pathologic immunohistochemical examination. Then, after careful discussion and demonstration by our multi-disciplinary team experts, we insisted on the diagnosis of ductal adenocarcinoma of the prostate and suggested that the original regimen of chemotherapy should be continued. Up-to-date, 14 months after the operation, the patient continues to survive while undergoing ongoing active treatment as recommended.

Black Phosphorus Quantum Dots Enhance the Radiosensitivity of Human Renal Cell Carcinoma Cells through Inhibition of DNA-PKcs Kinase.

Renal cell carcinoma (RCC) is one of the most aggressive urological malignancies and has a poor prognosis, especially in patients with metastasis. Although RCC is traditionally considered to be radioresistant, radiotherapy (RT) is still a common treatment for palliative management of metastatic RCC. Novel approaches are urgently needed to overcome radioresistance of RCC. Black phosphorus quantum dots (BPQDs) have recently received great attention due to their unique physicochemical properties and good biocompatibility. In the present study, we found that BPQDs enhance ionizing radiation (IR)-induced apoptotic cell death of RCC cells. BPQDs treatment significantly increases IR-induced DNA double-strand breaks (DSBs), as indicated by the neutral comet assay and the DSBs biomarkers γH2AX and 53BP1. Mechanistically, BPQDs can interact with purified DNA-protein kinase catalytic subunit (DNA-PKcs) and promote its kinase activity in vitro. BPQDs impair the autophosphorylation of DNA-PKcs at S2056, and this site phosphorylation is essential for efficient DNA DSBs repair and the release of DNA-PKcs from the damage sites. Consistent with this, BPQDs suppress nonhomologous end-joining (NHEJ) repair and lead to sustained high levels of autophosphorylated DNA-PKcs on the damaged sites. Moreover, animal experiments indicate that the combined approach with both BPQDs and IR displays better efficacy than monotreatment. These findings demonstrate that BPQDs have potential applications in radiosensitizing RCC cells.

The KLF4-p62 axis prevents vascular endothelial cell injury via the mTOR/S6K pathway and autophagy in diabetic kidney disease.

INTRODUCTION: Diabetic kidney disease (DKD) is a complication of systemic diabetic microangiopathy, which has a high risk of developing into end-stage renal disease and death. This study explored the mechanism underlying autophagy in DKD vascular endothelial cell injury. MATERIAL AND METHODS: DKD and vascular endothelial cell injury models were established using Sprague Dawley rats and human umbilical vein endothelial cells (HUVECs). HUVECs overexpressing Kruppel-like factor 4 (KLF4) were constructed by transient transfection of plasmids. Biochemical determination of urinary protein and blood urea nitrogen (BUN), superoxide dismutase (SOD), and creatinine (Scr) levels was performed. Renal pathology was observed by periodic acid-Schiff (PAS) staining. Cell Counting Kit-8 (CCK8), terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL), and immunocytochemistry (ICC) were used to analyse the growth and apoptosis of HUVECs. Microtubule-associated protein light chain 3 (LC3) expression was observed by immunofluorescence (IF). The reactive oxygen species (ROS) levels were measured using flow cytometry. Monocyte chemoattractant protein-1 (MCP-1), KLF4, and tumour necrosis factor alpha (TNF-α) levels were detected using enzyme-linked immunosorbent assay (ELISA). The expression of KLF4, p62 protein, and LC3 was analysed using reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR). S6 kinase (S6K), p70 ribosomal S6 kinase (p-S6K), Beclin1, ATG5, LC3, p62, Caspase-3, mammalian target of rapamycine (mTOR), and phsophorylated mTOR (p-mTOR) expressions were detected by western blotting. RESULTS: PAS-positive substances (polysaccharide and glycogen) and S6K protein levels increased, and LC3 protein expression decreased in DKD rats. The levels of urinary protein, BUN, and Scr increased, and KLF4 decreased in DKD rats. High glucose (HG) levels decreased the proliferation and increased the apoptosis rate of HUVECs. The expression of ROS, TNF-α, MCP-1, and p62 increased, while the expression of SOD, KLF4, Beclin1, ATG5, and LC3 decreased in HG-induced HUVECs. KLF4 overexpression significantly increased Beclin1, ATG5, and LC3 protein expression and decreased p62 protein expression compared to the oe-NC group in HG-induced HUVECs. KLF4 overexpression inhibits the expression of Caspase-3, p-mTOR, and p-S6K in HG-induced HUVECs. CONCLUSIONS: KLF4-p62 axis improved vascular endothelial cell injury by regulating inflammation and the mTOR/S6K pathway in DKD.

[Total PSA, PSA density and biopsy Gleason score in predicting the pathologic stage of prostate cancer].

OBJECTIVE: To evaluate the roles of total prostate specific antigen (tPSA), PSA density (PSAD) and biopsy Gleason score in predicting the pathologic stage of prostate cancer. METHODS: We retrospectively analyzed the clinical data of 124 cases of pathologically confirmed prostate adenocarcinoma, and divided them into Groups A (n=48) and B (n=76) based on the results of bone scanning, CT, MRI, tPSA, PSAD and postoperative biopsy Gleason score, the former with extraprostatic infiltration or distant metastasis, while the latter without. We compared the above parameters between the two groups, screened the main factors that influenced the pathologic staging of prostate cancer by multivariate logistic regression analysis, and appraised the value of each of the parameters in predicting the pathologic stage of prostate cancer with a relative operating characteristic (ROC) curve. RESULTS: The tPSA level and biopsy Gleason score were significantly higher in Group A than in B (P < 0.05). Multivariate logistic regression analysis showed that only tPSA could predict the pathologic stage of localized prostate cancer. The ROC curve exhibited that the combined use of tPSA and Gleason score had a better predicting value than other parameters (Gleason score + tPSA > tPSA > PSAD + tPSA + Gleason score). CONCLUSION: Total PSA remains a valuable predictor of the pathologic stage of prostate cancer, and its combination with Gleason score can further improve the predictive accuracy and contribute much to the treatment and prognosis of the disease.

Oral administration of hydroxylated-graphene quantum dots induces intestinal injury accompanying the loss of intestinal stem cells and proliferative progenitor cells.

Graphene quantum dots (GQDs) have gained significant attention in various biomedical applications. The physicochemical properties of these nanoparticles, including toxic effects, are largely determined by their surface modifications. Previous studies have demonstrated high in vitro cytotoxicity of the hydroxylated GQDs (OH-GQDs). The focus of this study was on the intestinal toxicity of OH-GQDs. Briefly, C57BL/6J mice were given daily oral gavage of 0.05, 0.5 or 5 mg/kg OH-GQD for 7 days, and the indices of intestinal damage were evaluated. Higher doses of the OH-GQDs caused significant intestinal injuries, such as enhanced intestinal permeability, shortened villi and crypt loss. The number of Lgr5+ intestinal stem cells also decreased dramatically upon OH-GQDs exposure, which also inhibited the Ki67+ proliferative progenitor cells. In addition, an increased number of crypt cells harboring the oxidized DNA base 8-OHdG and γH2AX foci were also detected in the intestines of OH-GQD-treated mice. Mechanistically, the OH-GQDs up-regulated both total and phosphorylated p53. Consistent with this, the average number of TUNEL+ and cleaved caspase-3+ apoptotic intestinal epithelial cells were significantly increased after OH-GQDs treatment. Finally, a 3-dimensional organoid culture was established using isolated crypts, and OH-GQDs treatment significantly reduced the size of the surviving intestinal organoids. Taken together, the intestinal toxicity of the OH-GQDs should be taken into account during biomedical applications.

Risk assessment models to evaluate the necessity of prostate biopsies in North Chinese patients with 4-50 ng/mL PSA.

BACKGROUND: Prostate-specific antigen (PSA) is widely used for prostate cancer screening, but low specificity results in high false positive rates of prostate biopsies. OBJECTIVE: To develop new risk assessment models to overcome the diagnostic limitation of PSA and reduce unnecessary prostate biopsies in North Chinese patients with 4-50 ng/mL PSA. METHODS: A total of 702 patients in seven hospitals with 4-10 and 10-50 ng/mL PSA, respectively, who had undergone transrectal ultrasound-guided prostate biopsies, were assessed. Analysis-modeling stage for several clinical indexes related to prostate cancer and renal function was carried out. Multiple logistic regression analyses were used to develop new risk assessment models of prostate cancer for both PSA level ranges 4-10 and 10-50 ng/mL. External validation stage of the new models was performed to assess the necessity of biopsy. RESULTS: The new models for both PSA ranges performed significantly better than PSA for detecting prostate cancers. Both models showed higher areas under the curves (0.937 and 0.873, respectively) compared with PSA alone (0.624 and 0.595), at pre-determined cut-off values of 0.1067 and 0.6183, respectively. Patients above the cut-off values were recommended for immediate biopsy, while the others were actively observed. External validation of the models showed significantly increased detection rates for prostate cancer (4-10 ng/mL group, 39.29% vs 17.79%, p=0.006; 10-50 ng/mL group, 71.83% vs 50.0%, p=0.015). CONCLUSIONS: We developed risk assessment models for North Chinese patients with 4-50 ng/mL PSA to reduce unnecessary prostate biopsies and increase the detection rate of prostate cancer.

[An analysis for the phenotype and genotype of autosomal dominant polycystic kidney disease from two Chinese families].

OBJECTIVE: To scan for mutations of polycystic kidney disease 1 gene (PKD1) in Chinese population in order to find some features about Chinese patients and a better approach to detect mutations. METHODS: Twenty-five PKD-affected individuals from twenty-one unrelated genealogies and sixteen controls participated in the study. Thirty-five blood samples and six tissues were obtained after receiving informed consent and were in accordance with institutional ethical guidelines. Genomic DNA was isolated from peripheral blood using standard procedures. PCR amplification of genomic DNA was performed to generate the aimed fragments. Amplified fragments were analyzed by denaturing gradient gel electrophoresis (DGGE). A GC clamp was attached to the 5' primer. After that, the abnormal fragments were sequenced on freshly amplified specific PCR products with the dideoxynucleotide chain termination method. Sequencing was performed for all samples to evaluate DGGE. RESULTS: Aimed fragments of exons 44 and 45 were amplified. DGGE detected eleven abnormal PCR fragments. Two novel mutations were identified by sequencing, included one nonsense mutation (C12217T) and one frameshift (12431delCT). In addition, one polymorphism (A50747C) was identified. The mutation detection rate is 8% in our study. CONCLUSION: Two novel pathogenic mutations were detected, including one nonsense mutation (C12217T) and one frameshift (12431delCT).

Ubenimex attenuates acquired sorafenib resistance in renal cell carcinoma by inhibiting Akt signaling in a lipophagy associated mechanism.

Sorafenib is used as first line treatment of renal cell carcinoma (RCC) due to the poor sensitivity to radiotherapy and chemotherapy of this malignancy; however, acquired resistance limits the application of sorafenib and its analogues. In this study, we explored a new strategy to overcome acquired resistance to sorafenib. The RCC cell lines 786-O and ACHN were cultured in presence of increasing concentrations of sorafenib to generate sorafenib-resistant cell lines, 786-O-R and ACHN-R. Interestingly, treatment with ubenimex (0.25 mg/ml) and 3-MA (2 mM) restored the sensitivity of resistant cell lines to sorafenib, indicating the involvement of autophagy in acquired resistance. High levels of autophagy flux were observed in resistant cells, and the opposite effects of ubenimex and 3-MA suggested a complex role for autophagy. While 3-MA abolished protection in sorafenib-resistant cells, ubenimex induced uncontrolled autophagy and autophagic cell death. Lipophagy, characterized by a lipid droplet cargo, was observed in RCC tissues and cells. In sorafenib-resistant cells, ubenimex inhibited the Akt signaling pathway that regulates autophagy. In summary, lipophagy participates in sorafenib-resistance of RCC, which could be reversed by interventions targeting the Akt pathway.

Spinal cord injury in rats treated using bone marrow mesenchymal stem-cell transplantation.

The aim of this study was to observe the effects of bone marrow mesenchymal stem-cell transplantation (BMSCs) in repairing acute spinal cord damage in rats and to examine the potential beneficial effects. 192 Wistar rats were randomized into 8 groups. Spinal cord injury was created. Behavior and limb functions were scored. Repairing effects of BMSCs transplantation was evaluated and compared. In vitro 4',6-diamidino-2-phenylindole (DAPI)-tagged BMSCs were observed, and whether they migrated to the area of spinal cord injury after intravenous tail injection was investigated. The expression of neuron-specific protein (NSE) on BMSCs was examined. Fifteen days after transplantation, the BMSCs-treated groups scored significantly higher in limb function tests than the untreated group. Pathological sections of the bone marrow after operation showed significant recovery in treated groups in comparison to the control group. After transplantation, small amounts of fluorescent-tagged BMSCs can be found in the blood vessels in the area of spinal cord injury, and fluorescent-tagged BMSCs were diffused in extravascular tissues, whereas the DAPI-tagged BMSCs could not be detected,and BrdU/NSE double-labeled cells were found in the injured marrow. BMSCs improve behavioral responses and can repair spinal cord injuries by migrating to the injured area, where they can differentiate into neurons.

Reciprocal regulation of hypoxia-inducible factor 2α and GLI1 expression associated with the radioresistance of renal cell carcinoma.

PURPOSE: Renal cell carcinoma (RCC) is often considered a radioresistant tumor, but the molecular mechanism underlying its radioresistance is poorly understood. This study explored the roles of hypoxia-inducible factor 2α (HIF2α) and sonic hedgehog (SHH)-GLI1 signaling in mediating the radioresistance of RCC cells and to unveil the interaction between these 2 signaling pathways. METHODS AND MATERIALS: The activities of SHH-GLI1 signaling pathway under normoxia and hypoxia in RCC cells were examined by real-time polymerase chain reaction, Western blot, and luciferase reporter assay. The expression of HIF2α and GLI1 in RCC patients was examined by immunohistochemistry, and their correlation was analyzed. Furthermore, RCC cells were treated with HIF2α-specific shRNA (sh-HIF2α), GLI1 inhibitor GANT61, or a combination to determine the effect of ionizing radiation (IR) on RCC cells based on clonogenic assay and double-strand break repair assay. RESULTS: RCC cells exhibited elevated SHH-GLI1 activities under hypoxia, which was mediated by HIF2α. Hypoxia induced GLI1 activation through SMO-independent pathways that could be ablated by PI3K inhibitor or MEK inhibitor. Remarkably, the SHH-GLI1 pathway also upregulated HIF2α expression in normoxia. Apparently, there was a positive correlation between HIF2α and GLI1 expression in RCC patients. The combination of sh-HIF2α and GLI1 inhibitor significantly sensitized RCC cells to IR. CONCLUSIONS: Cross-talk between the HIF2α and SHH-GLI1 pathways was demonstrated in RCC. Cotargeting these 2 pathways, significantly sensitizing RCC cells to IR, provides a novel strategy for RCC treatment.

Tumor-infiltrating regulatory T cells are positively correlated with angiogenic status in renal cell carcinoma.

BACKGROUND: Immune cells within a tumor microenvironment have shown modulatory effects on tumor angiogenic activity. Renal cell carcinoma (RCC) is a hypervascular tumor that reportedly increases the frequency of regulatory T cells (Tregs) in tumor tissues. This study investigated the correlation between Tregs infiltration and angiogenic status in RCC. METHODS: Thirty-six patients with RCC were enrolled in the present study, and twenty age-matched healthy donors were included as the control. Tregs were defined as CD4(+)CD25(high)CD127(low/-) T cells. The frequency of Tregs in peripheral blood and tumor infiltrating lymphocytes (TILs) were determined by flow cytometry. The expression of vascular endothelial growth factor (VEGF) in surgical resection specimens were measured with a commercial enzyme-linked immunosorbent assay (ELISA) kit. Microvessel density (MVD) was calculated on slides stained with CD34 antibody. Spearman's rank correlation was performed to evaluate the correlation between the frequencies of Tregs in TILs and VEGF values, as well as between frequencies of Tregs and MVD determinations. RESULTS: Compared to healthy controls, the frequency of peripheral blood Tregs was significantly increased in patients with RCC (P < 0.05). The percentage of tumor-infiltrating Tregs was higher than that of peripheral blood Tregs in patients with RCC (P < 0.01). In addition, the frequency of tumor-infiltrating Tregs was shown to significantly correlate with the pathological stage (P < 0.05) and nuclear grade (P < 0.01). Importantly, a significant positive correlation was observed between the frequency of tumor-infiltrating Tregs and VEGF protein expression (r = 0.51, P < 0.05), as well as between frequencies of Tregs and MVD score (r = 0.39, P < 0.05). CONCLUSIONS: These observations suggest that the high pro-angiogenic status of RCC may be associated with the accumulation of Tregs in the local microenvironment. Angiogenesis networks may be connected with immune tolerance units and cooperate with each other to facilitate tumor growth and progression.

Chronic administration of valproic acid inhibits PC3 cell growth by suppressing tumor angiogenesis in vivo.

AIM: Chromatin remodeling agents such as histone deacetylase inhibitors have been shown to modulate gene expression in tumor cells and inhibit tumor growth and angiogenesis. We investigated the mechanisms of chronic valproic acid (VPA) inhibiting PC3 cell growth in the study. METHODS: We established tumor xenografts of the PC3 cell line and investigated the effect of VPA chronic administration on tumor growth. Apoptosis in tumor tissue was measured using the TUNEL Detection Kit. We detected the effect of VPA chronic administration on histone acetylation; p21CIP1/WAF1 gene expression; vascular endothelial growth factor (VEGF) expression by reverse-transcription Polymerase Chain Reaction (PCR) analysis; immunohistochemistry; and Western Blotting. RESULT: In mouse models with established subcutaneous prostate (PC3), VPA treatment induced 70% inhibition of tumor growth without overt toxicity. Our result showed that chronic administration of VPA has an effect on tumor growth arrest and the effect was associated with increased histone acetylation, p21CIP1/WAF1 up-regulation, and VEGF down-regulation. CONCLUSION: We conclude that chronic VPA results in profound decreases in the proliferation of PC3 cells, not only by increasing histone H3 acetylation and up-regulating p21CIP1/WAF1 expression, but also by down-regulating VEGF.