Golgi Phosphoprotein Research Articles

Shedding of cancer susceptibility candidate 4 by the convertases PC7/furin unravels a novel secretory protein implicated in cancer progression

The proprotein convertases (PCs) are responsible for the maturation of precursor proteins, and are involved in multiple and critical biological processes. Over the past 30 years, the PCs have had great translational applications, but the physiological roles of PC7, the seventh member of the family, are still obscure. Searching for new substrates of PC7, a quantitative proteomics screen for selective enrichment of N-glycosylated polypeptides secreted from hepatic HuH7 cells identified two human type-II transmembrane proteins of unknown function(s): Cancer Susceptibility Candidate 4 (CASC4) and Golgi Phosphoprotein of 130 kDa (GPP130/GOLIM4). Concentrating on CASC4, its mutagenesis characterized the PC7/Furin-shedding site to occur at KR66↓NS, in HEK293 cells. We defined PC7 and Furin trafficking and activity, and demonstrated that CASC4 shedding occurs in acidic endosomes and/or in the trans-Golgi Network. Our data unraveled a cancer-protective role for CASC4, because siRNA silencing of endogenous CASC4 expression in the invasive triple-negative breast cancer human cell line MDA-MB-231 resulted in a significantly increased cellular migration and invasion. Conversely, MDA-MB-231 cells stably expressing CASC4 exhibited reduced migration and invasion, which can be explained by an increased number of paxillin-positive focal adhesions. This phenotypic cancer-protective role of CASC4 is reversed in cells overexpressing an optimally PC7/Furin-cleaved CASC4 mutant, or upon overexpression of the N-terminally convertase-generated membrane-bound segment. This phenotype was associated with increased formation of podosome-like structures, especially evident in cells overexpressing the N-terminal fragment. In accord, breast cancer patients’ data sets show that high CASC4 and PCSK7 expression levels predict a significantly worse prognosis compared to high CASC4 but low PCSK7 levels. In conclusion, CASC4 shedding not only disrupts its anti-migratory/invasive role, but also generates a membrane-bound fragment that drastically modifies the actin cytoskeleton, resulting in an enhanced cellular migration and invasion. This phenotype might be clinically relevant in the prognosis of breast cancer patients.

A novel protective role for microRNA-3135b in Golgi apparatus fragmentation induced by chemotherapy via GOLPH3/AKT1/mTOR axis in colorectal cancer cells

Chemotherapy activates a novel cytoplasmic DNA damage response resulting in Golgi apparatus fragmentation and cancer cell survival. This mechanism is regulated by Golgi phosphoprotein-3 (GOLPH3)/Myo18A/F-actin axis. Analyzing the functions of miR-3135b, a small non-coding RNA with unknown functions, we found that its forced overexpression attenuates the Golgi apparatus fragmentation induced by chemotherapeutic drugs in colorectal cancer (CRC) cells. First, we found that miR-3135b is downregulated in CRC cell lines and clinical tumors. Bioinformatic predictions showed that miR-3135b could be regulating protein-encoding genes involved in cell survival, resistance to chemotherapy, and Golgi dynamics. In agreement, ectopic transfection of miR-3135b in HCT-15 cancer cells significantly inhibited cell proliferation, sensitized cells to 5-fluoruracil (5-FU), and promoted late apoptosis and necrosis. Also, miR-3135b overexpression impaired the cell cycle progression in HCT-15 and SW-480 cancer cells. Because GOLPH3, a gene involved in maintenance of Golgi structure, was predicted as a potential target of miR-3135b, we studied their functional relationships in response to DNA damage induced by chemotherapy. Immunofluorescence and cellular ultrastructure experiments using antibodies against TGN38 protein, a trans-Golgi network marker, showed that 5-FU and doxorubicin treatments result in an apoptosis-independent stacks dispersal of the Golgi ribbon structure in both HCT-15 and SW-480 cells. Remarkably, these cellular effects were dramatically hindered by transfection of miR-3135b mimics. In addition, our functional studies confirmed that miR-3135b binds to the 3′-UTR of GOLPH3 proto-oncogene, and also reduces the levels of p-AKT1 (Ser473) and p-mTOR (Ser2448) signaling transducers, which are key in cell survival and autophagy activation. Moreover, we found that after treatment with 5-FU, TGN38 factor coimmunolocalizes with beclin-1 autophagic protein in discrete structures associated with the fragmented Golgi, suggesting that the activation of pro-survival autophagy is linked to loss of Golgi integrity. These cellular effects in autophagy and Golgi dispersal were reversed by miR-3135b. In summary, we provided experimental evidence suggesting for the first time a novel role for miR-3135b in the protection of chemotherapy-induced Golgi fragmentation via GOLPH3/AKT1/mTOR axis and protective autophagy in colorectal cancer cells.

<p>GOLPH3 Promotes Angiogenesis of Lung Adenocarcinoma by Regulating the Wnt/β-Catenin Signaling Pathway</p>

PurposeWe aim to investigate the role of Golgi phosphoprotein 3 (GOLPH3) and the possible regulation mechanism underlying lung adenocarcinoma (LADC).MethodsThe level of GOLPH3 was performed by quantitative real time (qRT)-PCR, Western blot and immunohistochemistry. Patient survival rate was analyzed by Kaplan–Meier method. MTT was used to detect cell viability. The levels of p-serine/threonine-protein kinase (Akt), Akt, p-p65, p65 and β-catenin were determined by Western blot. Cell apoptosis was tested using flow cytometry. Angiogenesis was determined by in vitro angiogenesis assay. qPCR and Western blot were performed to identify apoptotic protein B-cell lymphoma 2 (Bcl-2)/Bcl-2-associated X protein (Bax) and vascular endothelial growth factor (VEGF).ResultsGOLPH3 was highly expressed in LADC cell lines and tissues and was significantly correlated with poor overall survival among patients with LADC. Furthermore, GOLPH3 expression was reduced in A549 and H23 cells in a cisplatin-dependent manner. Silencing of GOLPH3 enhanced inhibition of A549 and H23 cells by cisplatin and suppressed the protein expression of p-Akt, while p-p65 expression remained stable. However, overexpression of GOLPH3 weakened the inhibition of A549 and H23 cells by cisplatin and improved the protein expression of p-Akt, while p-p65 expression remained stable. XAV939, an inhibitor of Wnt/β-catenin signaling pathway, decreased GOLPH3 overexpression-induced proliferation and enhanced cisplatin-induced angiogenesis inhibition and apoptosis, which was supported by the changes of VEGF, Bax and Bcl-2.ConclusionGOLPH3 promotes proliferation capacity in LADC through activating the Wnt/β-catenin signaling pathway.

Punicalagin inhibits the viability, migration, invasion, and EMT by regulating GOLPH3 in breast cancer cells

Breast cancer (BC) is one of the most common malignancies worldwide. Punicalagin (PN), which is a type of polyphenol, has been reported to act as a tumor suppressor. This study aimed to investigate the effects of PN on cellular process in BC and its molecular mechanism. The effects of various doses of PN on cell viability, migration, and invasion capacities of MCF-7 and MDA-MB-231 cells were detected by CCK-8, wound-healing, and Transwell assays. Golgi phosphoprotein 3 (GOLPH3) was then transfected into the cells with or without PN treatment, and GPLPH3 expression level was examined by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot, and expressions of epithelial–mesenchymal transition (EMT)-related protein matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9), E-Cadherin, and N-Cadherin were measured by Western blot. High dose of PN treatment (50 μM or higher) significantly inhibited viability, migration, and invasion of MCF-7 and MDA-MB-231 cells, while overexpressed GOLPH3 promoted cell viability, migration, and invasion, and partially reversed the effects of PN treatment on the BC cells. PN inhibited the expressions of GOLPH3, MMP-2, MMP-9, and N-Cadherin, and promoted E-Cadherin expression, while overexpression of GOLPH3 partly reversed above effects attributing to PN. Thus, PN suppresses cell viability and metastasis via regulating GOLPH3 in BC, which provides a possible therapeutic direction to the treatment of BC.

Oncogenic Roles of GOLPH3 in the Physiopathology of Cancer.

Golgi phosphoprotein 3 (GOLPH3), a Phosphatidylinositol 4-Phosphate [PI(4)P] effector at the Golgi, is required for Golgi ribbon structure maintenance, vesicle trafficking and Golgi glycosylation. GOLPH3 has been validated as an oncoprotein through combining integrative genomics with clinopathological and functional analyses. It is frequently amplified in several solid tumor types including melanoma, lung cancer, breast cancer, glioma, and colorectal cancer. Overexpression of GOLPH3 correlates with poor prognosis in multiple tumor types including 52% of breast cancers and 41% to 53% of glioblastoma. Roles of GOLPH3 in tumorigenesis may correlate with several cellular activities including: (i) regulating Golgi-to-plasma membrane trafficking and contributing to malignant secretory phenotypes; (ii) controlling the internalization and recycling of key signaling molecules or increasing the glycosylation of cancer relevant glycoproteins; and (iii) influencing the DNA damage response and maintenance of genomic stability. Here we summarize current knowledge on the oncogenic pathways involving GOLPH3 in human cancer, GOLPH3 influence on tumor metabolism and surrounding stroma, and its possible role in tumor metastasis formation.

Protosappanin B Exerts Anti-tumor Effects on Colon Cancer Cells via Inhibiting GOLPH3 Expression.

Protosappanin B (PSB) is a key active component of Lignum Sappan extract. Although the antiproliferative effects of Lignum Sappan extract have been demonstrated in various cancer cells, relatively little is known about the effects of PSB on tumor progression. The aim of this study was to explore the anti-tumor effects of PSB on human colon cancer cells by regulation of intracellular signaling pathways and Golgi phosphoprotein 3 (GOLPH3) expression in vitro and in vivo. Our results showed that PSB effectively inhibited the viability and migration of SW620 cells and induced apoptosis, but had poor effect on HCT116 cells. Furthermore, PSB significantly reduced the expression of p-AKT, p-p70S6K, β-catenin, and p-ERK1/2 proteins in SW620 cells, and this effect was reversed by the corresponding signaling pathway agonists. Interestingly, PSB could also suppress GOLPH3 expression of SW620 cells in a concentration-dependent manner, but SW620 cells transfected with lentiviral vectors overexpressing GOLPH3 can effectively resist the cytotoxic activity of PSB in vitro. The xenograft experiment of SW620 cells with LV-GOLPH3 confirmed that PSB distinctly inhibited the tumor growth via suppressing GOLPH3 expression. Collectively, these findings clarified a new anti-cancer mechanism of PSB through inhibition of GOLPH3 expression and intracellular signaling pathways in colon cancer cells. PSB may be a potential new drug for colon cancer.

FAP-a and GOLPH3 Are Hallmarks of DCIS Progression to Invasive Breast Cancer.

Biological markers that could predict the progression of ductal carcinoma in-situ (DCIS) to invasive breast cancer (IDC) are required urgently for personalized therapy for patients diagnosed with DCIS. As stroma was invaded by malignant cells, perturbed stromal-epithelial interactions would bring about tissue remodeling. With the specific expression of the fibroblast activation protein-alpha (FAP-a), Carcinoma-associated fibroblasts (CAFs) are the main cell populations in the remodeled tumor stroma. Golgi phosphoprotein 3 (GOLPH3), a documented oncogene possessing potent transforming capacity, is not only up-regulated in many tumors but also an efficient indicator of poor prognosis and more malignant tumors. The present study aimed to retrospectively evaluate the pathological value of FAP-a and GOLPH3 in predicting the recurrence or progression of DCIS to invasive breast cancer. Immunohistochemical techniques were applied to investigate the expression of FAP-a GOLPH3 in 449 cases of DCIS patients received extensive resection and with close follow-up, but not being treated with any form of chemo- or radio-therapy. The combination of FAP-a and GOLPH3 in predicating the recurrence or progression of DCIS into invasive breast cancer was specifically examined. The study demonstrated that the overexpression of FAP-a in stromal fibroblasts and GOLPH3 in carcinoma cells are highly predictive of DCIS recurrence and progression into invasive breast cancer. Both FAP-a and GOLPH3 have high specificity and sensitivity to predict the recurrence of DCIS. Moreover, the combination of FAP-a and GOLPH3 tends to further improve the specificity and sensitivity of DCIS recurrence by 9.72–10.31 and 2.72–3.63%, respectively. FAP-a and GOLPH3 serve as novel markers in predicting the recurrence or progression of DCIS into invasive breast cancer.

MiR-3150b inhibits hepatocellular carcinoma cell proliferation, migration and invasion by targeting GOLPH3

BackgroundIn this study, we aimed to explore the potential involvement of miR-3150b in hepatocellular carcinoma (HCC) carcinogenesis.MethodsThe expression of miR-3150b and Golgi phosphoprotein 3 (GOLPH3) was determined in HCC cell...

Golgi phosphoprotein 3 overexpression inhibits paclitaxel-induced apoptosis in HeLa cells by promoting autophagy

To investigate the effect of Golgi phosphoprotein 3 (Golph3) on paclitaxel- induced apoptosis and autophagy in HeLa cells. HeLa cells were transfected with a lentiviral vector expressing Golph3 or a small interfering RNA (siRNA) targeting Golph3 for up-regulation or down-regulation of Golph3 which was verified by Western blotting. The autophagic bodies in the cells were observed using transmission electron microscopy. The expression of autophagy markers p62 and LC3 were detected using Western blotting, and the cell apoptosis was examined by PI/Anexin V-FITC double staining and flow cytometry. The effects of blocking autophagy was evaluated by treatment of the cells with the autophagy inhibitor 3-MA. Transmission electron microscopy showed that the lentivirus-mediated overexpression of Golph3 significantly increased the number of autophagic bodies and interference of Golph3 expression significantly decreased autophagic bodies in HeLa cells. Western blotting showed that Golph3 overexpression caused an increased expression of LC3 and decreased the accumulation of p62 in the cells, and interference of Golph3 resulted in the reverse changes. The cell apoptosis induced by paclitaxel was significantly decreased in Golph3-overexpressing HeLa cells and increased in the cells with Golph3 knockdown (P>0.01). Treatment with 3-MA alone did not obviously affect HeLa cell apoptosis, but in cells with Golph3 knockdown, 3-MA significantly enhanced paclitaxel-induced apoptosis (P>0.01). Up-regulation of Golph3 promotes autophagy and inhibits paclitaxel-induced apoptosis, whereas suppression of Golph3 inhibits autophagy and enhances paclitaxel- induced apoptosis in HeLa cells.

MiR-3150b-3p inhibits the progression of colorectal cancer cells via targeting GOLPH3

The aim of this study was to investigate the function of miR-3150b-3p in malignant behaviors of colorectal cancer (CRC). The tumor-inhibitive effect of miR-3150b-3p was determined by cell viability, invasion,...

Co-delivery of GOLPH3 siRNA and gefitinib by cationic lipid-PLGA nanoparticles improves EGFR-targeted therapy for glioma.

Glioblastoma is one of the most aggressive types of brain tumor. Epidermal growth factor receptors (EGFRs) are overexpressed in glioma, and EGFR amplifications and mutations lead to rapid proliferation and invasion. EGFR-targeted therapy might be an effective treatment for glioma. Gefitinib (Ge) is an EGFR tyrosine kinase inhibitor (TKI), and Golgi phosphoprotein 3 (GOLPH3) expression is associated with worse glioma prognosis. Downregulation of GOLPH3 could promote EGFR degradation. Here, an angiopep-2 (A2)-modified cationic lipid-poly (lactic-co-glycolic acid) (PLGA) nanoparticle (A2-N) was developed that can release Ge and GOLPH3 siRNA (siGOLPH3) upon entering glioma cells and therefore acts as a combinatorial anti-tumor therapy. The in vitro and in vivo studies proved that A2-N/Ge/siGOLPH3 successfully crossed the blood-brain barrier (BBB) and targeted glioma. Released siGOLPH3 effectively silenced GOLPH3 mRNA expression and further promoted EGFR and p-EGFR degradation. Released Ge also markedly inhibited EGFR signaling. This combined EGFR-targeted action achieved remarkable anti-glioma effects and could be a safe and effective treatment for glioma. KEY MESSAGES: Angiopep-2-modified cationic lipid polymer can penetrate the BBB. Gefitinib can inhibit EGFR signaling and block the autophosphorylation of critical tyrosine residues on EGFR. GOLPH3 siRNA can be transfected into glioma and downregulate GLOPH3 expression. A2-N/Ge/siGOLPH3 can inhibit glioma growth.

Wiskott-Aldrich syndrome protein senses irradiation-induced DNA damage to coordinate the cell-protective Golgi dispersal response in human T and B lymphocytes

Wiskott-Aldrich syndrome (WAS) is an X-linked primary immune deficiency disorder resulting from Wiskott-Aldrich syndrome protein (WASp) deficiency. Lymphocytes from patients with WAS manifest increased DNA damage and lymphopenia from cell death, yet how WASp influences DNA damage-linked cell survival is unknown. Arecently described mechanism promoting cell survival after ionizing radiation (IR)-induced DNA damage involves fragmentation and dispersal of the Golgi apparatus, known as the Golgi-dispersal response (GDR), which uses the Golgi phosphoprotein 3 (GOLPH3)-DNA-dependent protein kinase (DNA-PK)-myosin XVIIIA-F-actin signaling pathway. We sought to define WASp's role in the DNA damage-induced GDR and its disruption as a contributor to the development of radiosensitivity-linked immunodeficiency in patients with WAS. In human TH and B-cell culture systems, DNA damage-induced GDR elicited by IR or radiomimetic chemotherapy was monitored in the presence or absence of WASp or GOLPH3 alone or both together. WASp deficiency completely prevents the development of IR-induced GDR in human TH and B cells, despite the high DNA damage load. Loss of WASp impedes nuclear translocation of GOLPH3 and its colocalization with the DNA-dependent protein kinase catalytic subunit (DNA-PKcs). Surprisingly, however, depletion of GOLPH3 alone or depolymerization of F-actin in WASp-sufficient TH cells still allows development of robust GDR, suggesting that WASp, but not GOLPH3, is essential for GDR and cell survival after IR-induced DNA-damage in human lymphocytes. The study identifies WASp as a novel effector of the nucleus-to-Golgi cell-survival pathway triggered by IR-induced DNA damage in cells of the hematolymphoid lineage and proposes an impaired GDR as a new cause for development of a "radiosensitive" form of immune dysregulation in patients with WAS.

C-Myc transactivates GP73 and promotes metastasis of hepatocellular carcinoma cells through GP73-mediated MMP-7 trafficking in a mildly hypoxic microenvironment

Golgi phosphoprotein 73 (GP73), encoded by GOLM1, is a highly expressed factor in hepatocellular carcinoma (HCC) cells and has been regarded for several years as a remarkable serum biomarker for the diagnosis of HCC. Recently, it was found that upregulation of GP73 promotes cancer metastasis, but the mechanism is complex, and it is even unclear how the gene is transactivated in HCC cells. In this study, it was discovered that c-Myc transactivated GP73 in a mildly hypoxic microenvironment and that the activation of c-Myc upregulated the expression of matrix metalloproteinase-7 (MMP-7). Moreover, it is shown that GP73 interacted with intracellular MMP-7 in the region of the cytoplasmic domain and facilitated the trafficking and secretion of MMP-7, resulting in cell metastasis. This study indicates that GP73 is transactivated by c-Myc and serves as a transporter in the trafficking of intracellular MMP-7 in HCC cells. These findings suggest that GP73 is a potential target for combating metastatic HCC.

Role of GOLPH3 and TPX2 in Neuroblastoma DNA Damage Response and Cell Resistance to Chemotherapy.

Neuroblastoma (NB) is an aggressive, relapse-prone infancy tumor of the sympathetic nervous system and is the leading cause of death among preschool age diseases, so the search for novel therapeutic targets is crucial. Golgi phosphoprotein 3 (GOLPH3) has been reported to be involved in the development, and in the DNA damage response, of various human cancers. Golgi dispersal is a common feature of DNA damage response in mammalian cells. Understanding how cells react to DNA damage is essential in order to recognize the systems used to escape from elimination. We induced DNA damage in two human neuroblastoma cell lines by curcumin. The exposure of neuroblastoma cells to curcumin induced: (a) up-regulation of GOLPH3+ cells; (b) augmentation of double-strand breaks; (c) Golgi fragmentation and dispersal throughout the cytoplasm; (d) increase of apoptosis and autophagy; (e) increased expression of TPX2 oncoprotein, able to repair DNA damage. Primary neuroblastoma samples analysis confirmed these observations. Our findings suggest that GOLPH3 expression levels may represent a clinical marker of neuroblastoma patients’ responsiveness to DNA damaging therapies—and of possible resistance to them. Novel molecules able to interfere with GOLPH3 and TPX2 pathways may have therapeutic benefits when used in combination with standard DNA damaging therapeutic agents in neuroblastoma

Clinicopathological significance of Golgi phosphoprotein 3 expression in papillary thyroid carcinoma

Objective: To investigate the expression of Golgi phosphoprotein 3 (GOLPH3) in papillary thyroid carcinoma (PTC) and its relationship with clinicopathological characteristics of PTC and American Thyroid Association (ATA) risk of recurrence stratification. Methods: The mRNA expression level of GOLPH3 in PTC tissues and the matched adjacent noncancerous tissues from 30 cases of PTC undergoing surgical operation in Fujian Provincial Hospital between March 2017 and April 2018 was detected by reverse transcription-quantitative PCR (RT-qPCR). The protein expression of GOLPH3 in PTC tissues and the matched adjacent noncancerous tissues of 135 cases of PTC between January 2013 and April 2018 was measured by immunohistochemistry. The correlation between the expression of GOLPH3 in PTC and clinicopathologic characteristics and ATA risk of recurrence stratification was analyzed. Results: The mRNA level of GOLPH3 in PTC tissues was significantly higher than that in adjacent noncancerous tissues (7.53±1.32 vs 3.64±1.44, P<0.001). The protein expression level of GOLPH3 in PTC tissues was significantly higher than that in adjacent noncancerous tissues [66(30, 95) vs 34(20, 72), P<0.001]. The expression of GOLPH3 was significantly correlated to the tumor size (P=0.026), extrathyroid invasion (P=0.016), lymph node metastasis (P=0.001) and TNM stage (P=0.027) in PTC. Multivariate logistic regression analysis showed that GOLPH3 expression was independently correlated to tumor size (OR=3.58, 95%CI: 1.19-15.46, P=0.017) and lymph node metastasis (OR=7.28, 95%CI: 2.43-10.08, P=0.002). The expression of GOLPH3 was positively correlated to ATA risk of recurrence stratification (P=0.041). Conclusions: Overexpression of GOLPH3 is associated with the development of PTC and poor prognosis in patients with PTC. Detection of GOLPH3 expression can help evaluate proliferative and metastatic potential of PTC, as well as the risk of postoperative recurrence in patients with PTC.

Therapeutic Targeting of Golgi Phosphoprotein 2 (GOLPH2) with Armed Antibodies: A Preclinical Study of Anti-GOLPH2 Antibody Drug Conjugates in Lung and Colorectal Cancer Models of Patient Derived Xenografts (PDX).

Golgi phosphoprotein 2 (GOLPH2) has been shown to be involved in chronic inflammatory processes and carcinogenesis. GOLPH2 is prominently overexpressed in hepatocellular carcinoma, melanoma, glioblastoma, prostate, lung, and colorectal cancer. With a low and tightly regulated expression in non-malignant tissues, GOLPH2 has been proposed as an attractive target for cancer therapy. However, GOLPH2 is predominantly located intracellularly and when situated outside of the cell it is proteolytically cleaved and shed from the cell surface. Until now, GOLPH2 has been regarded as an "undruggable" target. We sought to create antibodies that specifically bind to GOLPH2 overexpressing tumor cells. Antibodies binding to membranous GOLPH2 despite shedding of the protein were generated from a scFV library screening. These antibodies target the part of GOLPH2 that remains at the cell surface after proteolytic cleavage. These antibodies were then tested in vitro and in vivo. Two candidates (G2-1 and G2-2) showed target specific binding in vitro. Utilizing a tumor array (n = 128 tumors) with G2-2 and a reference antibody, a GOLPH2 expression scoring system was established. Rapid internalization of the antibodies was noted so this was exploited to deliver a toxic payload of pyrrolobenzodiazepine (PBD). In two patient-derived xenograft (PDX)-models, colorectal and lung cancer, the G2-2 antibody drug conjugate (ADC) displayed high efficacy with significant tumor responses (P = 0.001; P = 0.013) and improved survival (P = 0.0001; P = 0.0011) compared with controls. Treatment with GOLPH2-directed antibodies induces durable responses in colorectal and lung cancer models. With a robust companion assay for GOLPH2 positivity at hand our findings prepare for the translation into a clinical trial.

Diagnostic Utility of Serum Golgi Phosphoprotein 3 in Bladder Cancer Patients.

BackgroundThis study assessed whether serum Golgi phosphoprotein 3 (GOLPH3) could be used as a biomarker for detecting bladder cancer.Material/MethodsEnzyme-linked immunosorbent assay (ELISA) and immunohistochemistry (IHC) assay were performed to measure GOLPH3 expression in serum and tissue samples, respectively, of bladder cancer patients. The associations of serum GOLPH3 expression with clinicopathological factors and the diagnostic accuracy were statistically evaluated using the chi-square test and receiver operating characteristic (ROC) curve analysis.ResultsCompared with the healthy control group, serum GOLPH3 level was distinctly enhanced in bladder cancer patients (P<0.001). Moreover, compared to the non-malignant tissues, GOLPH3 showed positive expression in bladder cancer tissues. The abnormal GOLPH3 levels were tightly related to grade (P=0.018), tumor stage (P=0.000), lymph node status (P=0.030), and muscle invasion (P=0.012). ROC analysis showed that serum GOLPH3 exhibited a high diagnostic value to distinguish bladder cancer patients from healthy persons. The area under the ROC curve (AUC) was 0.948. The specificity and sensitivity were 92.5% and 83.8%, respectively.ConclusionsGOLPH3 was highly expressed in bladder cancer patients and could be used as a diagnostic tool.

Golgi phosphoprotein 3 (GOLPH3) promotes endometrial carcinoma cell invasion and migration by regulating the epithelial-mesenchymal transition.

BACKGROUND: Golgi phosphoprotein 3 (GOLPH3) is a novel oncogene overexpressed in several human cancers, but specific contributions to endometrial carcinoma (EC) have not been examined. The aims of this study were to evaluate the GOLPH3 expression in EC and investigate its functions in EC cell proliferation, migration, and survival.METHODS: The expression levels of GOLPH3 in EC patient samples and EC cell lines (HEC-1A, KLE, RL95-2, and Ishikawa) were examined using qRT-PCR, western blotting and immunohistochemistry. Further, EC cell lines with either ectopic GOLPH3 overexpression or knockdown were established, and the effects on proliferation, apoptosis, invasion, and migration were investigated in vitro using cell viability and transwell assays and in mice following cell injection.RESULTS: Compared to adjacent non-cancerous tissues, expression of GOLPH3 was significantly upregulated in EC tissues ( 0.05), and the expression level of GOPLPH3 was related to the grade of the tumor ( 0.05). The expression of GOLPH3 was also higher in all four EC cell lines than endometrial stromal cells (ESCs) ( 0.05). Moreover, GOLPH3 expression was greater in EC cell lines with high invasive capacity than in non-invasive EC cells ( 0.05). Knockdown of GOLPH3 inhibited EC cell proliferation and increased cell apoptosis in vitro. Further, knockdown of GOLPH3 also inhibited EC cell invasion and migration in vitro and in vivo by regulating the epithelial-mesenchymal transition (EMT). Conversely, GOLPH3 overexpression promoted proliferation and migration.CONCLUSIONS: The present study provides evidence that GOLPH3 promotes EMT and metastasis of EC cells and predicts the risk of EC progression, highlighting its potential as a therapeutic target for this malignancy.

Golgi Phosphoprotein 3 Promotes Malignant Phenotypes via FAK/Raf/MEK and Wnt/β-Catenin Signaling Pathways in Human Renal Cell Carcinoma.

Golgi phosphoprotein 3 (GOLPH3), a proto-oncogene product, is significantly increased during the progression of several types of cancer. However, its biological role and underlying mechanism in the development of renal cell carcinoma (RCC) remain poorly understood. In this study, GOLPH3 was found to be highly expressed in RCC specimens compared to the corresponding non-tumor tissues. In vitro, ectopic overexpression of GOLPH3 substantially promoted the proliferative and invasive capacity of RCC cells, while the depletion of GOLPH3 significantly inhibited proliferation and invasion of RCC cells. Furthermore, the average tumor volume was significantly increased in mice injected with 769-P cells highly expressing GOLPH3, whereas GOLPH3 knockdown reduced the tumor growth rate. Mechanistically, using a high-throughput phospho-proteome array verified by Western blotting, we have identified that phosphorylated proteins (FAK, Raf1, MEK, and GSK3β) were upregulated, activating, in turn, FAK/Raf1/MEK and Wnt/β-catenin signaling pathways in RCC cells. Taken together, our findings demonstrate that GOLPH3, whose expression is related to enhanced cell proliferation and invasion via activation of GOLPH3-FAK/Raf1/MEK axis or Wnt/β-catenin signaling pathways, may provide a new therapeutic target to treat renal cell carcinoma.

Golgi phosphoprotein-3 promotes invasiveness of gastric cancer cells through the mTOR signalling pathway.

Golgi phosphoprotein-3 (GOLPH3) is an oncogene that is overexpressed in multiple cancers and is associated with poor prognosis. The aim of this study was to examine the impact of GOLPH3 on the migration and metastasis of gastric cancer cells. Following the shRNA-mediated knockdown of GOLPH3, we analyzed cytoskeletal reorganization and cell invasion, migration and adhesion, and determined the impact of components of the mammalian target of the rapamycin (mTOR) signalling pathway. The GOLPH3 mRNA and protein expression were significantly lower in both SGC-7901 and MKN-28 cells as compared with poorly-differentiated BGC-823 cells. The GOLPH3 knockdown also significantly reduced cell invasion in all three cell lines through reduced migration as compared with the non-targeting control sequence group. The GOLPH3 knockdown also reduced F-actin in all three cell lines, and decreased cell adhesion in BGC-823 and SGC-7901 cells. Finally, p-mTOR, p70S6K, p-4EBP1 and RhoA protein levels were significantly downregulated in shGOLPH3-1-treated cells. In conclusion, GOLPH3 increased in poorly-differentiated gastric cancer cells, activating the mTOR-70S6K/4EBP1-RhoA signalling pathway to promote the migration and metastasis of gastric cancer cells.