lncRNA MAGI2-AS3 suppresses castration-resistant prostate cancer proliferation and migration via the miR-106a-5p/RAB31 axis.

Prostate cancer (PCa) is a common malignant cancer in elderly males in Western countries. Whole-genome sequencing confirmed that long non-coding RNAs (lncRNAs) are frequently altered in castration-resistant prostate cancer (CRPC) and promote drug resistance to cancer therapy. Therefore, elucidating the prospective role of lncRNAs in PCa oncogenesis and progression is of remarkable clinical significance. In this study, gene expression in prostate tissues was determined using RNA-sequencing datasets, and the gene diagnostic and prognostic values of CRPC were analyzed using bioinformatics. Further, the expression levels and clinical significance of MAGI2 Antisense RNA 3 (MAGI2-AS3) in PCa clinical specimens were evaluated. The tumor-suppressive activity of MAGI2-AS3 was functionally explored in PCa cell lines and animal xenograft models. MAGI2-AS3 was found to be aberrantly decreased in CRPC and was negatively correlated with Gleason score and lymph node status. Notably, low MAGI2-AS3 expression positively correlated with poorer survival in patients with PCa. The overexpression of MAGI2-AS3 significantly inhibited the proliferation and migration of PCa in vitro and in vivo. Mechanistically, MAGI2-AS3 could play a tumor suppressor function in CRPC through a novel miR-106a-5p/RAB31 regulatory network and could be a target for future cancer therapy.

Initial Experience of Simultaneous Combined use of Percutaneous Nephrolithotomy and Flexible Ureteroscopy in Complex Renal Calculi: A Novel Surgical Technique of 'Through-Through' Approach.

BACKGROUND: For complex branched renal calculi, the endoscopic combined intrarenal surgery (ECIRS) is worldwide prevalent. This study aimed to present a novel surgical technique of percutaneous nephrolithotomy combined with antegrade flexible ureteroscopy which is named 'Through-through' approach. METHODS: We retrospectively analyzed the data of 68 patients with complex renal calculi who underwent combined PNL and flexible ureteroscopy surgery using 'Through-through' approach at our center between August 2019 and December 2021. The 'Through-through' approach to surgery was indicated in residual calyceal calculi that neither rigid nephroscope nor retrograde flexible ureteroscope could reach. The brief procedure of this technique involved determining the direction of targeted calyces with the nephroscope first, followed by putting flexible ureteroscope into the targeted calyx through the nephroscope instrument channel and basketing or dusting residual calculi through the flexible ureteroscope instrument channel. RESULTS: The mean maximum stone diameter was 4.0 ± 0.4 cm. The mean operative duration was 100.1 ± 18.0 minutes, and mean hemoglobin loss was 21.4 ± 5.1 g/L. In all 68 patients, calculi were cleared in 62 patients, and the stone free rate was 91.2%. Five patients underwent further surgery after 2 weeks because of significant residual calculi. One patient that had a 6 mm residual stone chose observational follow-up. Ten patients emerged with postoperative fever but did not progress to uroseptic shock. There were no Clavien grade ≥ III complications, and none of the patients required blood transfusion. CONCLUSION: The 'Through-through' approach is safe, feasible and effective for complex renal calculi patients. It is a complementary solution to the failed endoscopic combined intrarenal surgery.

A new treatment of concealed penis: symmetrical pterygoid flap surgery.

PURPOSE: Considerable controversy exists regarding the surgery for concealed penis. We describe a new technique for repairing concealed penis by symmetrical pterygoid flap surgery. METHODS: From January 2016 to July 2022, we evaluated 181 cases of concealed penis that were surgically treated using the symmetrical pterygoid flap surgery. We measured the penile size preoperative and 2, 4, 12 weeks, and 1 year postoperative to confirm the improvement. A questionnaire was administered to the patients and parents to assess satisfaction regarding penile size, morphology, and hygiene. RESULT: The perpendicular penile length was1.59±0.32cm preoperative and 3.82±1.02 cm after the procedure (p < 0.05), and 4.21±1.91cm after one year of postoperative (p < 0.05). The overall satisfaction of patients was 97.89%, while the overall satisfaction of older children patients (age>7) was 75.24%. Parents focus more on the penile exposure size, while patients focus more on the penile morphology. Almost every patient had postoperative penile foreskin edema. However, this symptom had spontaneously resolved by 4-6 weeks. The complications such as skin necrosis, tissue contracture, or wound infection were 4.42%. CONCLUSION: The symmetrical pterygoid flap surgery is an effective surgical technique for the management of concealed penis in children producing predictable results and excellent satisfaction of the parents and patients.

Lycopene enhances the sensitivity of castration-resistant prostate cancer to enzalutamide through the AKT/EZH2/ androgen receptor signaling pathway.

Enzalutamide is an effective drug for the treatment of castration-resistant prostate cancer (CRPC), but acquired enzalutamide resistance is usually unavoidable within the short term in many patients. Lycopene, a safe and effective phytochemical, has been documented to have anticancer activity in a variety of tumors, especially for prostate cancer (PCa). The aim of this study was to provide data support for the combination of lycopene and enzalutamide in the treatment of CRPC. To this end, tissues from patients with primary prostate cancer (PPC) and CRPC were examined by immunohistochemical analysis and found that p-AKT and p-EZH2 were overexpressed in CRPC. Furthermore, Kaplan-Meier survival analysis showed that the high expression of p-AKT and p-EZH2 may be related to the poor prognosis of patients. In addition, the expression of p-AKT, p-EZH2 and androgen receptor (AR) were significantly down-regulated in 22RV1 and C4-2B cells and the proliferation and invasion of CRPC cells were inhibited after treatment with lycopene, while SC79 (an AKT agonist) markedly rescue this effect. Of note, a combination of lycopene and enzalutamide significantly inhibited the proliferation and invasion of CRPC cells in vitro, as well as tumor growth and bone metastasis in vivo. These results suggest that the enhanced antitumor effects of enzalutamide by lycopene may be related to the reduction of AR protein levels through lycopene-mediated inhibition of AKT/EZH2 pathway, which may provide a new approach to improve the efficacy of enzalutamide in CRPC.

Identification of the metabolic signatures of prostate cancer by mass spectrometry-based plasma and urine metabolomics analysis.

OBJECTIVE: Prostate cancer (PCa) is one of the most commonly diagnosed cancers among men which is associated with profound metabolic changes. Systematic analysis of the metabolic alterations and identification of new biomarkers may benefit PCa diagnosis and a deep understanding of the pathological mechanism. The purpose of this study was to determine the metabolic features of PCa. METHODS: Plasma and urine metabolites from 89 prostate cancer (PCa) patients, 84 benign prostatic hyperplasia (BPH) patients, and 70 healthy males were analyzed using LC-MS/MS and GC-MS. The Orthogonalised Partial Least Squares Discriminant Analysis (OPLS-DA) was used to find the significantly changed metabolites. The clinical value of the candidate markers was examined by receiver operating characteristic curve analysis and compared with prostate-specific antigen (PSA). RESULTS: Multivariate statistical analyses found a series of altered metabolites, which related to the urea cycle, tricarboxylic acid cycle (TCA), fatty acid metabolism, and the glycine cleavage system. Plasma Glu/Gln showed the highest predictive value (AUC = 0.984) when differentiating PCa patients from healthy controls, with a higher sensitivity than PSA (96.6% vs. 94.4%). Both Glu/Gln and PSA displayed a low specificity when differentiating PCa patients from BPH patients (<53.2%), while the combination of Glu/Gln and PSA can further increase the diagnostic specificity to 66.9%. CONCLUSIONS: The present study showed the metabolic features of PCa, provided strong evidence that the amide nitrogen and the energy metabolic pathways could be a valuable source of markers for PCa. Several candidate markers identified in this study were clinically valuable for further assessment.

Long noncoding RNA HOTAIR regulates the invasion and metastasis of prostate cancer by targeting hepaCAM.

BACKGROUND: The role of HOX transcript antisense RNA (HOTAIR) has been proven to be important in tumorigenesis. However, how this molecule promotes metastasis and invasion in PCa is still unclear. METHODS: The relationship between HOTAIR and hepatocellular adhesion molecule (hepaCAM) in PCa was identified by immunohistochemistry, immunofluorescence, plasmid transfection, quantitative real-time PCR and immunoblotting. The regulatory effects of HOTAIR on hepaCAM and MAPK signalling and their key roles in PCa metastasis were investigated in vitro. RESULTS: The expression of HOTAIR was inversely correlated with hepaCAM in the blood and tissue of PCa patients. Here, hepaCAM was identified as a novel target gene of HOTAIR and was critical for the invasiveness of PCa. HOTAIR recruited PRC2 to the hepaCAM promoter, resulting in high levels of H3K27me3 and the absence of hepaCAM with an abnormally activated MAPK pathway. Both HOTAIR depletion and EZH2 inhibition could induce hepaCAM re-expression with inhibitory MAPK signalling and decrease the invasive and metastatic capabilities of PCa cells. CONCLUSIONS: This study demonstrates that HOTAIR promotes invasion and metastasis of PCa by decreasing the inhibitory effect of hepaCAM on MAPK signalling. Therefore, the HOTAIR/hepaCAM/MAPK axis may provide a new avenue towards therapeutic strategies and prognostic indicators for advanced prostate cancer.

MicroRNA-199b-3p suppresses malignant proliferation by targeting Phospholipase Cε and correlated with poor prognosis in prostate cancer.

OBJECTIVES: MicroRNA-199b-3p (miR-199b-3p) plays a crucial role in the malignant development of various cancers, but little known in prostate cancer (PCa). The aim of our study was to demonstrate the function of miR-199b-3p in PCa. METHODS: Quantitative real-time polymerase chain reaction (RT-qPCR) was used to detect miR-199b-3p expression in PCa and benign prostatic hyperplasia (BPH) tissue samples. In addition, we examined the relationship between the poor prognosis in PCa and miR-199b-3p. Western blot was used to analyze the expression of Phospholipase Cε (PLCε). CCK8 and colony-forming assays were applied to detect the proliferation of PCa. EdU assay is used to detect PCa cells uptake of EdU. Luciferase reporter assay was applied to analyze the binding between miR-199b-3p and PLCε. RESULTS: It has been shown that miR-199b-3p in PCa was significantly lower than that in benign prostatic hyperplasia and correlated with poor prognosis. Meanwhile, upregulation of miR-199b-3p can prominently inhibit the proliferation of PCa cells, while its down-regulation triggered opposite result. PLCε was identified as the downstream binding target gene and negatively associated with that of miR-199b-3p. CONCLUSION: miR-199b-3p suppresses malignant proliferation by inhibiting PLCε in prostate cancer in vitro and vivo.

Ionizing Radiation Combined with PARP1 Inhibitor Reduces Radioresistance in Prostate Cancer with RB1/TP53 Loss.

Tumor suppressor genes RB1 and TP53 are altered frequently in prostate cancer (PC), whether RB1 and TP53 inactivation promotes radioresistance remains unclear. Herein, we demonstrated that RB1 loss enhanced ionizing radiation (IR)-induced DNA damage to inhibit cell proliferation and promote cellular senescence through a TP53-dependent pathway in LNCaP cells. Furthermore, the stabilization of TP53 was regulated by ATM-mediated phosphorylation of MDM2 at Ser395. However, inactivation of RB1/TP53 reversed DNA damage-induced cellular senescence and promoted radiation survival. Importantly, combined with PARP1 inhibitor restored radiosensitivity. This finding provides a potential approach for the therapy of PC with RB1/TP53 inactivation.

PLCε regulates metabolism and metastasis signaling via HIF-1α/MEK/ERK pathway in prostate cancer.

Phospholipase C-ε (PLCε) is frequently overexpressed in tumors and plays an important role in the regulation of tumorigenesis. Although great progress has been made in understanding biological roles of PLCε, the relevant molecular mechanisms underlying its pro-tumor activity remain largely unclear. Here, we demonstrated that PLCε knockdown reduced cell metastasis, glucose consumption and lactate production in a manner that depended on hypoxia inducible factor 1α (HIF-1α) expression in prostate cancer cells. Interestingly, our findings showed that the expression levels of PLCε were positively associated with those of HIF-1α in clinical prostate carcinoma samples. Knockdown of PLCε impaired HIF-1α levels and transcriptional activity by regulating the extracellular-signal-regulated kinase pathway, and blocking HIF-1α nuclear translocation. Furthermore, PLCε could interact with the von Hippel-Lindau E3 ligase complex to modulate the stability of HIF-1α. Collectively, our findings demonstrate that PLCε could be a crucial positive regulator of HIF-1α, which would promote PLCε-enhanced tumorigenesis.

Phospholipase Cε Regulates Prostate Cancer Lipid Metabolism and Proliferation by Targeting AMP-Activated Protein Kinase (AMPK)/Sterol Regulatory Element-Binding Protein 1 (SREBP-1) Signaling Pathway.

BACKGROUND Metabolic reprogramming is a common characteristic of numerous kinds of tumors, including prostate cancer (PCa). Tumor metabolism such as lipid metabolism provides sufficient lipids for tumor cell division and rapid growing as well as a vital source for formation of new cellular membranes. Phospholipase Cε (PLCε) is an oncogene that can drive proliferation, progression, and lipid metabolism of tumors, but its effect in lipid metabolism of PCa is not clear. MATERIAL AND METHODS Benign prostatic hyperplasia (BPH) and PCa tissue specimens were assessed for SREBP-1, FASN, and PLCε by immunohistochemistry, and PLCε was knocked-down by a lentiviral short hairpin RNA. The mRNA and protein level expression of related factors were tested by qPCR and Western blot analyses. Cell proliferation was assessed by clone formation, CCK-8, and Ki-67 assays. Nile red and oil red O staining were performed to detect endogenous lipid levels. Immunofluorescence was used to localize the protein of SREBP-1. Finally, a tumor xenograft assay of nude mice was performed to assess the role of PLCε in prostate tumor generation. RESULTS We found that overexpression of PLCε indicates low PFS in PCa and is involved in metastasis of PCa, and that the PLCε/AMPK/SREBP-1 signaling network promotes the progression of PCa through lipid metabolism in vivo and in vitro. CONCLUSIONS This study is the first to discover the lethal role of PLCε in lipid metabolism and malignant behavior of PCa, elucidation PCa occurrence and progression.

PLCε knockdown overcomes drug resistance to androgen receptor antagonist in castration-resistant prostate cancer by suppressing the wnt3a/ß-catenin pathway.

Most prostate cancers (Pcas) develop into castration-resistant prostate cancer (CRPC) after receiving androgen deprivation therapy (ADT). The expression levels of PLCε and wnt3a are increased in Pca and regulate androgen receptor (AR) activity. However, the biological function and mechanisms of PLCε and wnt3a in CRPC remain unknown. In this study, we found that the expression levels of PLCε, wnt3a, and AR were significantly increased in CRPC tissues as well as bicalutamide-resistant-LNCaP and enzalutamide-resistant-LNCaP cells. In addition, PLCε knockdown partly restored the sensitivity of drug-resistant cells to bicalutamide and enzalutamide by inhibiting the activity of the wnt3a/ß-catenin/AR signaling axis. Interestingly, the resistance of LNCaP cells docetaxel is related to PLCε but not the wnt3a/ß-catenin pathway. We also found that the combination of PLCε knockdown and enzalutamide treatment synergistically suppressed cell proliferation, tumor growth, and bone metastasis using in vitro and in vivo experiments. Our study revealed that PLCε is involved in the progression of drug-resistance in CRPC and could be a new target for the treatment of CRPC.

Phospholipase C (PLC)ε Promotes Androgen Receptor Antagonist Resistance via the Bone Morphogenetic Protein (BMP)-6/SMAD Axis in a Castration-Resistant Prostate Cancer Cell Line.

BACKGROUND Primary therapy for patients with advanced prostate cancer (PCa) consists of androgen deprivation therapy targeting the androgen receptor (AR) axis. However, most tumors progress to castration-resistant prostate cancer (CRPC) within 18-24 months. The purpose of the present study was to investigate the mechanisms through which PCa acquires drug resistance after long-term treatment with AR antagonists. MATERIAL AND METHODS Online database analysis and bioinformatics analysis were performed to identify signaling activated during anti-androgen treatment. MTT assay was used to detect cell viability. RT-qPCR was performed to examine the mRNA expression of the indicated genes. Colony formation assay was performed to observe cell proliferation. Transwell assay was conducted to demonstrate invasive ability. Protein levels were determined by Western blot analysis and immunofluorescence assays. RESULTS An online database search and bioinformatics analysis indicated that bone morphogenetic protein (BMP)-6/SMAD signaling was activated in enzalutamide-resistant LNCaP cells. Furthermore, this signaling interaction was experimentally verified in bicalutamide- and enzalutamide-resistant LNCaP cells, which may be regulated by phospholipase C (PLC)ε and induced cell proliferation and invasion. Of note, a positive correlation was observed between PLCε and BMP-6 in CRPC tissue samples, which may promote bone metastasis and suggests a poor prognosis. CONCLUSIONS The present results suggest that targeting of PLCε/BMP-6/SMAD signaling may increase the sensitivity of CRPC to AR antagonists and inhibit tumor progression.

Knockdown of Phospholipase Cε (PLCε) Inhibits Cell Proliferation via Phosphatase and Tensin Homolog Deleted on Chromosome 10 (PTEN)/AKT Signaling Pathway in Human Prostate Cancer.

BACKGROUND Phospholipase Cε (PLCε), a member of the plc family, has been extensively studied to reveal its role in the regulation of different cell functions, but understanding of the underlying mechanisms remains limited. In the present study, we explored the effects of PLCε on PTEN (phosphatase and tensin homolog deleted on chromosome 10) in cell proliferation in prostate cancer cells. MATERIAL AND METHODS We assessed PLCε and PTEN expression in human benign prostate tissues compared to prostate cancer tissues by immunohistochemistry. Lentivirus-shPLCε (LV-shPLCε) was designed to silence PLCε expression in DU145 and PC3 cell lines, and the effectiveness was tested by qRT-PCR and Western blotting. MTT assay and colony formation assay were conducted to observe cell proliferation. Western blotting and immunofluorescence assays were used to detect changed PTEN expression in DU145. RESULTS We observed that PLCε expression was reduced in human benign prostate tissues compared to prostate cancer tissues, while PTEN expression showed the opposite trend. Silencing of the PLCε gene significantly inhibited cell proliferation in DU145 and PC3 cell lines. DU145 is a PTEN-expressing cell, while PC3 is PTEN-deficient. After infection by LV-shPLCε, we noticed that PTEN expression was up-regulated in DU145 cells but not in PC3 cells. Furthermore, we found that PLCε gene knockdown decreased P-AKT protein levels, but AKT protein levels were not affected. Immunofluorescence assays showed that PTEN expression had an intracellular distribution change in the DU145 cell line, and Western blot analysis showed that PTEN was obviously up-regulated in cell nucleus and cytoplasm. CONCLUSIONS PLCε is an oncogene, and knockdown of expression of PLCe inhibits PCa cells proliferation via the PTEN/AKT signaling pathway.

Computed tomography angiography with 3D reconstruction in diagnosis of hydronephrosis cause by aberrant renal vessel: A case report and mini review.

BACKGROUND: Congenital hydronephrosis is often caused by aberrant renal vessel and it is difficult to be diagnosed and treated at the early stage due to lack of the significant symptoms. Although current medical diagnosis tools are widely used, the aberrant renal vessel cannot be displayed very well in the images. OBJECTIVE: To investigate whether applying computed tomography (CT) angiography with 3D reconstruction can improve efficacy in diagnose of this congenital hydronephrosis. MATERIALS AND METHODS: A male patient of 18 years old was diagnosed as hydronephrosis of left kidney. A CT angiography with 3D reconstruction was evaluated in diagnosis of the prenatal hydronephrosis compared to ultrasound (US) and intravenous urogram (IVU). RESULTS: US and IVU images were able to display the dilation of left pelvic and the dilated calyces, and the thinner of renal parenchyma on the left kidney (Grade II-IV), but failed to detect the causing of hydro-nephrosis. CT angiography with 3D reconstruction provided accurate images of the dilated renal pelvic, upper segment of the ureter, and an aberrant vessel bundle overcrossing at the left renal pelvic-ureter junction as well. The aberrant vessel could be revealed during surgery. CONCLUSIONS: A CT angiography with 3D reconstruction provides a more accurate diagnostic approach for the congenital hydronephrosis caused by aberrant renal vessel. Thus, it can offer surgeons very important information in the pre-surgery planning.

The SMAD2/3 pathway is involved in hepaCAM-induced apoptosis by inhibiting the nuclear translocation of SMAD2/3 in bladder cancer cells.

The aim of this study was to explore the correlation between hepatocyte cell adhesion molecule (hepaCAM) and SMAD family member 2/3 (SMAD2/3) in bladder carcinoma, and the involvement of the SMAD2/3 pathway in hepaCAM-induced tumor apoptosis. Immunohistochemistry was used to measure hepaCAM and p-SMAD2/3 protein levels in bladder cancer tissues. Flow cytometry and Hoechst staining were used to study the effect of hepaCAM on cellular apoptosis. Western blot was employed to determine the expression of hepaCAM and SMAD2/3/caspase pathway molecules using a hepaCAM overexpression adenovirus, a caspase inhibitor (Z-VAD-FMK), and a SMAD2/3 activator (transforming growth factor (TGF)-ß1), respectively. Translocation of p-SMAD2/3 was measured by immunofluorescence and western blot. HepaCAM proteins were significantly decreased (P < 0.05), while p-SMAD2/3 proteins were remarkably increased (P < 0.05) in bladder carcinoma compared to adjacent tissues. However, the low hepaCAM and high p-SMAD2/3 were not statistically associated with clinicopathological characteristics of the patients. A negative linear correlation between hepaCAM and p-SMAD2/3 was observed according to Pearson analysis (r = -0.712/-0.724, P = 0.008/0.011). Overexpression of hepaCAM activated caspase 3/8/9 and downregulated poly-ADP ribose polymerase (PARP) and p-SMAD2/3. Treatment of bladder cancer cells with Z-VAD-FMK + hepaCAM significantly downregulated procaspase 3/8/9 and PARP and induced cellular apoptosis, compared with that using Z-VAD-FMK alone. Similarly, combined treatment of TGF-ß1 + hepaCAM significantly downregulated p-SMAD2/3, procaspase 3/8/9, and PARP and induced apoptosis of bladder cancer cells, compared with TGF-ß1 alone. Overexpression of hepaCAM prevented the p-SMAD2/3 translocation from the cytoplasm to the nucleus in bladder cancer cells BIU-87 and T24. Our findings uncover that the p-SMAD2/3 pathway is critical for hepaCAM-induced cancer cell apoptosis and provide valuable insights for current and future Ad-hepaCAM and p-SMAD2/3 clinical trials.

Knockdown of PLCε inhibits inflammatory cytokine release via STAT3 phosphorylation in human bladder cancer cells.

Phospholipase Cε (PLCε) is a multifunctional enzyme implicated in inflammatory functions. There are limited data, however, on how PLCε can alter inflammatory cytokine by affecting downstream pathways. Recent studies suggest that inflammation is likely to have an important role in transitional cell carcinoma of bladder (TCCB) and cancer disease progression. Here, we showed that PLCε and p-STAT3 expression were both elevated in TCCB tissues compared to adjacent tissues, and the increase of PLCε level was associated with the increase of p-STAT3 level. Then, knockdown of PLCε using adenovirus-shPLCε significantly decreased inflammatory cytokine (IL-6, TNF-α, IL-1ß) expression and inflammation-associated gene (TLR4, MyD88, p-STAT3) expression. Furthermore, we demonstrated that PLCε knockdown blocked LPS-induced inflammatory cytokine and p-STAT3 expression. Additionally, we found that combined treatment of STAT3 inhibitor S3I-201 with adenovirus-shPLCε exhibited synergistic inhibitory effects on expression of p-STAT3. Our results suggested that STAT3 phosphorylation is involved in PLCε-mediated inflammatory cytokine release. Our research is of potential importance in drug development programs using PLCε as a therapeutic target for TCCB.

Overexpression of HepaCAM inhibits cell viability and motility through suppressing nucleus translocation of androgen receptor and ERK signaling in prostate cancer.

BACKGROUND: HepaCAM is suppressed in a variety of human cancers, and involved in cell adhesion, growth, migration, invasion, and survival. However, the expression and function of HepaCAM in prostate cancer are still unknown. METHODS: HepaCAM expression has been detected by RT-PCR, Western blotting and immunohistochemistry staining in prostate cell lines RWPE-1, LNCap, DU145, PC3, and in 75 human prostate tissue specimens, respectively. Meanwhile, the cell proliferation ability was detected by WST-8 assay. The role of HepaCAM in prostate cancer cell migration and invasion was examined by wound healing and transwell assay. And flow cytometry was used to observe the apoptosis of prostate cancer cells. Then we detected changes of Androgen Receptor translocation and ERK signaling using immunofluorescence staining and western blot after overexpression of HepaCAM. RESULTS: The HepaCAM expression was significantly down-regulated in prostate cancer tissues and undetected in prostate cancer cells. However, the low HepaCAM expression was not statistically associated with clinicopathological characteristics of prostate cancer. Overexpression of HepaCAM in prostate cancer cells decreased the cell proliferation, migration and invasion, and induced the cell apoptosis. Meanwhile, HepaCAM prevented the androgen receptor translocation from the cytoplasm to the nucleus and down-regulated the MAPK/ERK signaling. CONCLUSION: Our results suggested that HepaCAM acted as a tumor suppressor in prostate cancer. HepaCAM inhibited cell viability and motility which might be through suppressing the nuclear translocation of Androgen Receptor and down-regulating the ERK signaling. Therefore, it was indicated that HepaCAM may be a potential therapeutic target for prostate cancer.

HepaCAM inhibits clear cell renal carcinoma 786-0 cell proliferation via blocking PKCε translocation from cytoplasm to plasma membrane.

Hepatocyte cell adhesion molecule (HepaCAM) plays a crucial role in tumor progression and has been recognized as a novel tumor suppressor gene. The high protein expression level of protein kinase Cε (PKCε) has been discovered in many tumor types. In the present study, we determined HepaCAM and PKCε protein levels in human clear cell renal cell carcinoma (ccRCC) tissues and analyzed the correlation between them. We observed an inverse relationship in the expression of HepaCAM and PKCε in ccRCC and adjacent normal tissues. In ccRCC tissue, HepaCAM expression was undetectable while PKCε expression was high; the opposite was found in the adjacent normal tissue. Western blot analysis demonstrated that PKCε cytosolic protein levels increased while plasma membrane protein levels decreased without any change in total protein following infection of the ccRCC cell line 786-0 with adenovirus-GFP-HepaCAM (Ad-GFP-HepaCAM). Moreover, the application of Ad-GFP-HepaCAM combined with a PKCε-specific translocation inhibitor (εV1-2) effectively inhibited 786-0 cell growth. Ad-mediated expression of HepaCAM in 786-0 cells reduced the levels of phosphorylated AKT and cyclin D1 and inhibited cell proliferation. In summary, our studies point to interesting connections between HepaCAM and PKCε in tissues and in vitro. HepaCAM may prevent the translocation of PKCε from cytosolic to particulate fractions, resulting in the inhibition of 786-0 cell proliferation. Therapeutic manipulation of these novel protein targets may provide new ways of treating ccRCC.

Nuclear factor-κB signaling pathway is involved in phospholipase Cε-regulated proliferation in human renal cell carcinoma cells.

Phospholipase Cε (PLCε), a downstream effector of small GTPase superfamily, has been identified to play a crucial role in tumorigenesis. Previously, our studies have showed that PLCε promotes proliferation of renal cell carcinoma (RCC) cells. However, the molecular mechanisms by which PLCε enhances the survival phenotype of RCC cells are still not fully instructed. In the present study, we first demonstrated that PLCε was highly expressed and had a close correlation with Ki67 protein expression in RCC tissue samples. Further, we found that downregulation of PLCε expression repressed growth and induced apoptosis in RCC cells. In addition, we reported a mechanism by which knockdown of PLCε gene potently suppressed the nuclear factor kappa (NF-κB) signaling pathway through action on inhibitor of κB kinase. Moreover, silencing PLCε gene decreased vascular endothelial growth factor (VEGF) expression, which was a downstream growth factor of NF-κB signaling pathway. Finally, downregulation of VEGF was severely enhanced by treatment cells with NF-κB specific inhibitor BAY11-7028 in PLCε knockdown cells. Taken together, these findings suggest that PLCε promotes RCC cell growth via NF-κB-mediated upregulation of VEGF.

hepaCAM and p-mTOR closely correlate in bladder transitional cell carcinoma and hepaCAM expression inhibits proliferation via an AMPK/mTOR dependent pathway in human bladder cancer cells.

PURPOSE: We explored the correlation between hepaCAM and activated p-mTOR in bladder transitional cell carcinoma. We also determined whether the antiproliferation effect of hepaCAM is associated with the AMPK/mTOR pathway. MATERIALS AND METHODS: We performed quantitative reverse transcriptase-polymerase chain reaction to determine hepaCAM mRNA expression as well as Western blot to measure hepaCAM and p-mTOR protein levels in 25 men and 5 women. Disease was Ta-T1 in 7 patients, T2-T4 in 23, grade 1 in 13, grade 2 in 9, grade 3 in 8, primary in 13 and recurrent in 17. The WST-8 assay was used to study the effect of hepaCAM on cellular proliferation. p-AMPK, p-mTOR, total AMPK, total mTOR, c-Myc and cyclin D1 were also determined by Western blot. RESULTS: hepaCAM mRNA and protein levels were significantly decreased, while p-mTOR protein was remarkably increased in bladder transitional cell carcinoma compared to adjacent tissues (each p<0.01). Spearman correlation analysis revealed that the hepaCAM decrease was associated with an increase in p-mTOR (r=-0.533, p=0.002). Also, hepaCAM inhibited the proliferation of human bladder transitional cell carcinoma cells. hepaCAM over expression activated AMPK and down-regulated p-mTOR, and its targets c-Myc and cyclin D1. Treatment with the AMPK inhibitor compound C prevented the antiproliferation effect of hepaCAM. Compound C completely blocked hepaCAM induced activation of AMPK and down-regulation of p-mTOR and its targets c-Myc and cyclin D1. CONCLUSIONS: Results suggest an important correlation between hepaCAM and p-mTOR. hepaCAM can inhibit bladder cancer cell proliferation through an AMPK/mTOR dependent pathway.