High expression of GOLPH3 in esophageal squamous cell carcinoma correlates with poor prognosis. PLoS One. 2012;7:e45622. [PMID: 23056210 PMCID: PMC3462781 DOI: 10.1371/journal.pone.0045622]

Protosappanin B enhances the chemosensitivity of 5-fluorouracil in colon adenocarcinoma by regulating the LINC00612/microRNA-590-3p/Golgi phosphoprotein 3 axis

BACKGROUND

5-fluorouracil (5-FU) is conventionally used in chemotherapy for colon adenocarcinomas. Acquired resistance of 5-FU remains a clinical challenge in colon cancer, and efforts to develop targeted agents to reduce resistance have not yielded success. Protosappanin B (PSB), the main component of Lignum Sappan extract, is known to exhibit anti-tumor effects. However, whether and how PSB could improve 5-FU resistance in colon cancer have not yet been established. In this study, we aimed to explore the effects and underlying mechanisms of PSB in 5-FU-induced chemoresistance in colon adenocarcinoma.

METHODS

Forty-seven paired colon cancer tissue samples from patients who received 5-FU chemotherapy were collected as clinical samples. Two 5-FU resistant colon cancer cell lines were established for in vitro experiments. Reverse transcription-quantitative PCR (RT-qPCR) was performed to determine the mRNA and microRNA (miRNA) expression levels in colon adenocarcinoma tissues and cell lines. Cell Counting Kit-8 (CCK-8) and flow cytometry assays were performed to evaluate cell proliferation and apoptosis, respectively.

RESULTS

LINC00612 was highly expressed in colon adenocarcinoma samples and 5-FU resistant colon cancer cells. LINC00612 knockdown enhances 5-FU chemosensitivity in 5-FU resistant cells. Notably, PSB treatment attenuated LINC00612 expression in 5-FU resistant colon adenocarcinoma cells. Moreover, PSB treatment reversed the increase in LINC00612-induced 5-FU resistance. Mechanistically, LINC00612 specifically bound to miR-590-3p, which promoted 5-FU resistance in colon adenocarcinoma cells and attenuated the inhibitory effect of LINC00612 on GOLPH3 expression.

CONCLUSION

PSB attenuates 5-FU chemoresistance in colon adenocarcinoma by regulating the LINC00612/miRNA-590-3p/GOLPH3 axis.

GOLPH3 promotes tumor malignancy via inhibition of ferroptosis by upregulating SLC7A11 in cholangiocarcinoma

Golgi phosphoprotein 3 (GOLPH3) has been reported as an oncogene in various tumors; however, the role and function of GOLPH3 and its relevant molecular mechanism in cholangiocarcinoma (CCA) are unclear. Herein, GOLPH3 expression in CCA tissues was observed to be significantly higher than that in paired adjacent noncancerous tissues. Clinicopathological analysis showed that GOLPH3 expression correlated positively with the tumor-node-metastasis stage. In addition, GOLPH3 expression correlated inversely with the overall survival of patients with CCA. Multivariate analysis showed that GOLPH3 was an independent prognostic factor for patients with CCA. Transcriptome analysis (RNA sequencing) of GOLPH3 knockdown cells showed that the expression levels of nine ferroptosis-related genes were significantly changed, indicating the important biological function of GOLPH3 in ferroptosis in CCA cells. Furthermore, GOLPH3 knockdown could significantly promote Erastin-induced ferroptosis in vitro and suppress tumor growth in vivo. Overexpression of GOLPH3 had the opposite effect on this phenotype. Further studies revealed that GOLPH3 knockdown was significantly associated with a decrease in cysteine content, an accumulation of the lipid peroxidation product malondialdehyde, an increase in reactive oxygen species, and sensitized CCA cells to Erastin-induced ferroptosis. Moreover, changes in GOLPH3 expression were found to be consistent with the expression of light chain subunit solute carrier family 7 member 11 (SLC7A11). Thus, our study suggested that GOLPH3 functions as an oncoprotein in CCA and may suppress ferroptosis by facilitating SLC7A11 expression, suggesting that GOLPH3 could serve as a therapeutic target for CCA treatment.

Clinicopathologic and prognostic implications of Golgi Phosphoprotein 3 in colorectal cancer: A meta-analysis

Background

Golgi Phosphoprotein 3 (GOLPH3) has been implicated in the development of colorectal cancer (CRC). Nevertheless, the clinicopathological and prognostic roles of GOLPH3 in CRC remain undefined. We thus did a meta-analysis to assess GOLPH3 association with the clinicopathological characteristics of patients and evaluate the prognostic significance of GOLPH3 in CRC.

Methods

An electronic search for relevant articles was conducted in the PubMed, Cochrane Library, Web of Science, Medline, Embase, CNKI, and WanFang databases. Two independent reviewers searched all the literature and finished the data extraction and quality assessment. Odds ratio (OR) or hazard ratio (HR) with 95% confidence interval (CI) were used to assess estimates. Stata software (version12.0) was employed to analyze the data.

Results

A total of 8 published studies were eligible (N = 723 participants). Meta-analysis revealed that GOLPH3 was found to be highly expressed in tumor tissues compared to that of adjacent colorectal tissues (OR, 2.63), and overexpression of GOLPH3 had significant relationship with advanced clinical stage (OR, 3.42). GOLPH3 expression was not correlated with gender (OR, 0.89), age (OR, 0.95), positive lymphatic metastasis (OR, 1.27), tumor size (OR, 1.12), poor differentiation of tumor (OR, 0.56) or T stage (OR, 0.70). Moreover, GOLPH3 overexpression was not associated with worse overall survival (OS) (HR = 1.14, 95% CI: 0.42–1.86, P>0.05) and disease-free survival (DFS) (HR = 0.80, 95% CI:-0.26–1.86, P>0.05).

Conclusions

GOLPH3 overexpression is correlated with tumor stage, which is an adverse clinicopathological characteristic of CRC. But, GOLPH3 can not serve as a useful biomarker in evaluating the progression of CRC.

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 (P< 0.05), and the expression level of GOPLPH3 was related to the grade of the tumor (P< 0.05). The expression of GOLPH3 was also higher in all four EC cell lines than endometrial stromal cells (ESCs) (P< 0.05). Moreover, GOLPH3 expression was greater in EC cell lines with high invasive capacity than in non-invasive EC cells (P< 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.

Diagnostic Utility of Serum Golgi Phosphoprotein 3 in Bladder Cancer Patients

Background

This study assessed whether serum Golgi phosphoprotein 3 (GOLPH3) could be used as a biomarker for detecting bladder cancer.

Material/Methods

Enzyme-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.

Results

Compared 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.

Conclusions

GOLPH3 was highly expressed in bladder cancer patients and could be used as a diagnostic tool.

Golgi phosphoprotein 3 sensitizes the tumour suppression effect of gefitinib on gliomas

Objectives

We previously reported that Golgi phosphoprotein 3 (GOLPH3) promotes glioma progression by inhibiting EGFR endocytosis and degradation, leading to EGFR accumulation and PI3K‐AKT pathway over‐activation. In the current study, we examine whether GOLPH3 affects the response of glioma cells to gefitinib, an EGFR selective inhibitor.

Materials and Methods

The expression of GOLPH3 and EGFR in glioma cells was detected by immunofluorescence and immunoblotting. The cell viability or growth in vitro was determined by CCK‐8, EdU incorporation and clonogenic assays. The primary glioma cells were cultured by trypsin and mechanical digestion. The transwell invasion assay was used to examine the primary glioma cell motility. Intracranial glioma model in nude mice were established to explore the sensitivity of gefitinib to GOLPH3 high cancer cells in vivo.

Results

Both the immortalized and primary glioma cells with GOLPH3 over‐expression hold higher EGFR protein levels on the cell membrane and exhibited higher sensitivity to gefitinib. In addition, primary glioma cells with higher GOLPH3 level exhibited stronger proliferation behaviour. Importantly, GOLPH3 enhanced the anti‐tumour effect of gefitinib in vivo. Consistently, after gefitinib treatment, tumours derived from GOLPH3 over‐expression cells exhibited lower Ki67‐positive and higher cleaved caspase‐3–positive cells than control tumours.

Conclusions

Our results demonstrate that GOLPH3 increases the sensitivity of glioma cells to gefitinib. Our study provides foundation for further exploring whether GOLPH3 high gliomas will be more sensitive to anti‐EGFR therapy in clinic and give ideas for developing new possible treatments for individual glioma patients.

The knocking down of the oncoprotein Golgi phosphoprotein 3 in T98G cells of glioblastoma multiforme disrupts cell migration by affecting focal adhesion dynamics in a focal adhesion kinase-dependent manner

Golgi phosphoprotein 3 (GOLPH3) is a conserved protein of the Golgi apparatus that in humans has been implicated in tumorigenesis. However, the precise function of GOLPH3 in malignant transformation is still unknown. Nevertheless, clinicopathological data shows that in more than a dozen kinds of cancer, including gliomas, GOLPH3 could be found overexpressed, which correlates with poor prognosis. Experimental data shows that overexpression of GOLPH3 leads to transformation of primary cells and to tumor growth enhancement. Conversely, the knocking down of GOLPH3 in GOLPH3-overexpressing tumor cells reduces tumorigenic features, such as cell proliferation and cell migration and invasion. The cumulative evidence indicate that GOLPH3 is an oncoprotein that promotes tumorigenicity by a mechanism that impact at different levels in different types of cells, including the sorting of Golgi glycosyltransferases, signaling pathways, and the actin cytoskeleton. How GOLPH3 connects mechanistically these processes has not been determined yet. Further studies are important to have a more complete understanding of the role of GOLPH3 as oncoprotein. Given the genetic diversity in cancer, a still outstanding aspect is how in this inherent heterogeneity GOLPH3 could possibly exert its oncogenic function. We have aimed to evaluate the contribution of GOLPH3 overexpression in the malignant phenotype of different types of tumor cells. Here, we analyzed the effect on cell migration that resulted from stable, RNAi-mediated knocking down of GOLPH3 in T98G cells of glioblastoma multiforme, a human glioma cell line with unique features. We found that the reduction of GOLPH3 levels produced dramatic changes in cell morphology, involving rearrangements of the actin cytoskeleton and reduction in the number and dynamics of focal adhesions. These effects correlated with decreased cell migration and invasion due to affected persistence and directionality of cell motility. Moreover, the knocking down of GOLPH3 also caused a reduction in autoactivation of focal adhesion kinase (FAK), a cytoplasmic tyrosine kinase that regulates focal adhesions. Our data support a model in which GOLPH3 in T98G cells promotes cell migration by stimulating the activity of FAK.

Novel role of microRNA-126 in digestive system cancers: From bench to bedside

MicroRNAs (miRNAs) are ubiquitously expressed, small, non-coding RNAs that regulate the expression of approximately 30% of the human genes at the post-transcriptional level. miRNAs have emerged as crucial modulators in the initiation and progression of various diseases, including numerous cancer types. The high incidence rate of cancer and the large number of cancer-associated cases of mortality are mostly due to a lack of effective treatments and biomarkers for early diagnosis. Therefore there is an urgent requirement to further understand the underlying mechanisms of tumorigenesis. MicroRNA-126 (miR-126) is significantly downregulated in a number of tumor types and is commonly identified as a tumor suppressor in digestive system cancers (DSCs). miR-126 downregulates various oncogenes, including disintegrin and metalloproteinase domain-containing protein 9, v-crk sarcoma virus CT10 oncogene homolog and phosphoinositide-3-kinase regulatory subunit 2. These genes are involved in a number of tumor-associated signaling pathways, including angiogenesis, epithelial-mensenchymal transition and metastasis pathways. The aim of the current review was to summarize the role of miR-126 in DSCs, in terms of its dysregulation, target genes and associated signaling pathways. In addition, the current review has discussed the potential clinical application of miR-126 as a biomarker and therapeutic target for DSCs.

GOLPH3: a Golgi phosphatidylinositol(4)phosphate effector that directs vesicle trafficking and drives cancer

GOLPH3 is a peripheral membrane protein localized to the Golgi and its vesicles, but its purpose had been unclear. We found that GOLPH3 binds specifically to the phosphoinositide phosphatidylinositol(4)phosphate [PtdIns(4)P], which functions at the Golgi to promote vesicle exit for trafficking to the plasma membrane. PtdIns(4)P is enriched at the trans-Golgi and so recruits GOLPH3. Here, a GOLPH3 complex is formed when it binds to myosin18A (MYO18A), which binds F-actin. This complex generates a pulling force to extract vesicles from the Golgi; interference with this GOLPH3 complex results in dramatically reduced vesicle trafficking. The GOLPH3 complex has been identified as a driver of cancer in humans, likely through multiple mechanisms that activate secretory trafficking. In this review, we summarize the literature that identifies the nature of the GOLPH3 complex and its role in cancer. We also consider the GOLPH3 complex as a hub with the potential to reveal regulation of the Golgi and suggest the possibility of GOLPH3 complex inhibition as a therapeutic approach in cancer.

Golgi phosphoprotein 3 promotes glioma progression via inhibiting Rab5-mediated endocytosis and degradation of epidermal growth factor receptor

Background

Golgi phosphoprotein 3 (GOLPH3) is associated with worse prognosis of gliomas, but its role and mechanism in glioma progression remain largely unknown. This study aimed to explore the role and mechanism of GOLPH3 in glioma progression.

Methods

The expression of GOLPH3 in glioma tissues was detected by quantitative PCR, immunoblotting, and immunohistochemistry. GOLPH3's effect on glioma progression was examined using cell growth assays and an intracranial glioma model. The effect of GOLPH3 on epidermal growth factor receptor (EGFR) stability, endocytosis, and degradation was examined by immunoblotting and immunofluorescence. The activity of Rab5 was checked by glutathione S-transferase pulldown assay.

Results

GOLPH3 was upregulated in gliomas, and its downregulation inhibited glioma cell proliferation both in vitro and in vivo. Furthermore, GOLPH3 depletion dampened EGFR signaling by enhancing EGFR endocytosis, driving EGFR into late endosome and promoting lysosome-mediated degradation. Interestingly, GOLPH3 bound to Rab5 and GOLPH3 downregulation promoted the activation of Rab5. In addition, Rab5 depletion abolished the effect of GOLPH3 on EGFR endocytosis and degradation.

Conclusion

Our results imply that GOLPH3 promotes glioma cell proliferation via inhibiting Rab5-mediated endocytosis and degradation of EGFR, thereby activating the phosphatidylinositol-3 kinase (PI3K)-Akt-mammalian target of rapamycin (mTOR) signaling pathway. We find a new mechanism by which GOLPH3 promotes tumor progression through regulating cell surface receptor trafficking. Extensive and intensive understanding of the role of GOLPH3 in glioma progression may provide an opportunity to develop a novel molecular therapeutic target for gliomas.

GOLPH3 promotes cell proliferation and tumorigenicity in esophageal squamous cell carcinoma via mTOR and Wnt/β‑catenin signal activation

The authors' previous study demonstrated that Golgi phosphoprotein 3 (GOLPH3) was significantly overexpressed in esophageal squamous cell carcinoma (ESCC), correlating with poor patient survival. In the present study, GOLPH3 stable overexpression and knockdown KYSE‑140 cell lines were constructed. Cell proliferation, colony formation, cell cycle progression and tumorigenesis assays were performed. The results revealed that GOLPH3 promoted ESCC cell growth and proliferation. The effects of GOLPH3 on the mechanistic target of rapamycin (mTOR) and Wnt/β‑catenin signaling pathways were investigated using western blot analyis and dual‑luciferase reporter assays, and were observed to be activated in cells with GOLPH3 overexpression. Furthermore, overexpression of GOLPH3 resulted in the downregulation of p21 protein, upregulation of cyclin D1 and increased retinoblastoma‑associated protein phosphorylation, consequently leading to accelerated cell cycle progression. In addition, GOLPH3 knockdown resulted in reversed effects. The results of the current study suggest that GOLPH3 serves an important role in promoting tumorigenicity of ESCC via mTOR and Wnt/β‑catenin signaling pathway activation.

Upregulation of sex-determining region Y-box 9 (SOX9) promotes cell proliferation and tumorigenicity in esophageal squamous cell carcinoma

Sex-determining region Y-box 9 (SOX9), a vital transcription factor, play important roles in numerous biological and pathological processes. However, the clinical significance and biological role of SOX9 expression has not been characterized in human esophageal squamous cell cancer (ESCC). Herein, we found that SOX9 was markedly upregulated, at both mRNA and protein level, in ESCC cell lines and ESCC tissues and that SOX9 expression was significantly correlated with tumor clinical stage, T classification, N classification, M classification, pathological differentiation, and shorter overall survival. The proliferation and tumorigenicity of ESCC cells were dramatically induced by SOX9 overexpression but were inhibited by SOX9 knockdown both in vitro and in vivo. Moreover, we demonstrated that upregulation of SOX9 increased the expression of phosphorylated Akt, the cyclin-dependent kinase (CDK) regulator cyclin D1, phosphorylated forkhead box O (FOXO)1, and phosphorylated FOXO3, but SOX9 downregulation decreased their expression, whereas the levels of the CDK inhibitors p21^Cip1 and p27^Kip1 were attenuated in SOX9-transduced cells. Taken together, our results suggest that SOX9 plays an important role in promoting the proliferation and tumorigenesis of ESCC and may represent a novel prognostic marker for the disease.

[Effect of phosphoinositide 4-phosphate on invasion and migration of human glioma U87 cells]

OBJECTIVE

To investigate the effect of phosphoinositide 4-phosphate (PI4P) on human glioma U87 cells and the mechanism of action of PI4P in the development of human glioma through the overexpression or silencing of PI4P in human glioma U87 cells, and to provide a new target for basic research and clinical treatment of glioma.

METHODS

LV-Helper1, LV-Helper2, pWPXLd-PI4P, and pLL3.7-shPI4P were used to package pWPXLd-PI4P and pLL3.7-shPI4P lentiviruses. The U87-GFP (PI4P-overexpression control group), U87-GFP-PI4P (PI4P-overexpression experimental group), U87-Scramble (PI4P-silencing control group), and U87-shPI4P (PI4P-silencing experimental group) cell lines were established. Wound-healing assay and Transwell assay were used to evaluate cell migration and invasion, and Western blot was used to measure the expression of PI4P in each group.

RESULTS

Western blot detected the expression of exogenous PI4P in the U87-GFP-PI4P cell line, and the U87-shPI4P cell line showed reduced expression of PI4P compared with the U87-Scramble cell line in the control group. The U87-GFP-PI4P cell line with PI4P overexpression had a significantly stronger ability of migration than the U87-GFP cell line in the control group (P<0.01); the U87-shPI4P cell line with PI4P silencing had a reduced ability of migration than the U87-Scramble cell line in the control group (P<0.01). The U87 cell line with PI4P overexpression had a significantly stronger invasion ability than the control group (P<0.05); after PI4P silencing, the experimental group showed a significant reduction in invasion ability compared with the control group (P<0.05).

CONCLUSIONS

In human glioma U87 cells, PI4P can promote the invasion and migration of glioma cells and may become a new target in the basic research and clinical treatment of glioma.

miR-186 inhibits cell proliferation of prostate cancer by targeting GOLPH3

Prostate cancer is one of the leading causes of cancer deaths among men, many miRNAs have been demonstrated to play critical role in the progression of prostate cancer, miR-186 suppresses the progression of many tumors, such as bladder cancer and glioma. Previous study shows miR-186 is downregulated in prostate cancer tissues, and is a good prognosis for prostate cancer patients. In this study, we found miR-186 was downregulated in prostate cancer cells and tissues, overexpression of miR-186 inhibited cell proliferation and tumorigenesis in vitro determined by MTT assay, colony formation assay and soft agar growth assay, whereas knockdown of miR-186 reduced these effects. Cell cycle analysis found miR-186 overexpression arrested cell cycle in G0/G1 phase, and reduced p21 and p27 levels, and enhanced Cyclin D1 and the phosphorylation of Rb levels, suggesting miR-186 blocked G1/S transition. A novel oncogene Golgi phhosphoprotein 3 (GOLPH3) was the target of miR-186, miR-186 bound to the 3'UTR of GOLPH3. Moreover, miR-186 was negatively correlated with GOLPH3 in prostate cancer tissues. In conclusion, our study suggested miR-186 inhibited cell proliferation through targeting oncogene GOLPH3.

miR-199a-5p regulates β1 integrin through Ets-1 to suppress invasion in breast cancer

Increasing evidence has revealed that miR‐199a‐5p is actively involved in tumor invasion and metastasis as well as in the decline of breast cancer tissues. In this research, overexpression of miR‐199a‐5p weakened motility and invasion of breast cancer cells MCF‐7 and MDA‐MB‐231. Upregulation of Ets‐1 increased breast cancer cell invasion, but the mechanism by which miR‐199a‐5p modulates activation of Ets‐1 in breast cancer was not clarified. We investigated the relationship between miR‐199a‐5p and Ets‐1 on the basis of 158 primary breast cancer case specimens, and the results showed that Ets‐1 expression was inversely correlated with endogenous miR‐199a‐5p. Overexpression of miR‐199a‐5p reduced the mRNA and protein levels of Ets‐1 in MCF‐7 and MDA‐MB‐231 cells, whereas anti‐miR‐199a‐5p elevated Ets‐1. siRNA‐mediated Ets‐1 knockdown phenocopied the inhibition invasion of miR‐199a‐5p in vitro. Moreover, luciferase reporter assay revealed that miR‐199a‐5p directly targeted 3′‐UTR of Ets‐1 mRNA. This research revealed that miR‐199a‐5p could descend the levels of β1 integrin by targeting 3′‐UTR of Ets‐1 to alleviate the invasion of breast cancer via FAK/Src/Akt/mTOR signaling pathway. Our results provide insight into the regulation of β1 integrin through miR‐199a‐5p‐mediated Ets‐1 silence and will help in designing new therapeutic strategies to inhibit signal pathways induced by miR‐199a‐5p in breast cancer invasion.

Onco-Golgi: The Missed Target

The Golgi apparatus or complex, a highly dynamic organelle, is a factory in which proteins are processed and sorted for transport to various target organelles.(1) It was first discovered by Camillo Golgi in 1898 and was described as an intracellular reticular apparatus stained by the 'black reaction' in neuronal cells.(1,2) Despite of several research works, this complex remains one of the most inexplicable structures of the cytoplasmic organelles.

Correlation of GOLPH3 Gene with Wnt Signaling Pathway in Human Colon Cancer Cells

Objective: Overexpression of GOLPH3 in colorectal cancer tissue may promote cell proliferation and activate the Wnt signaling pathway. We investigated the correlation between GOLPH3 gene expression and the Wnt signaling pathway to explore the mechanism of the overexpression of GOLPH3 gene which promotes proliferation in human colon cancer cells.

Methods: We measured expression of GOLPH3 mRNA in the human colon cancer cell lines HCT116, HT29, SW480 and SW620 by RT-PCR, and the cells with the highest expression were selected and divided into four groups: negative control, GOLPH3 siRNA transfection (siRNA-GOLPH3), Akt inhibitor (Tricinbine), and glycogen synthase kinase (GSK)-3β inhibitor (TWS119). After human colon cancer cells were transfected with siRNA-GOLPH3, we used RT-PCR to investigate the silencing effect of GOLPH3 gene. We assessed the activity of the Wnt signaling pathway in all groups using the Topflash method. Proliferation and apoptosis of colon cancer SW620 cells were detected by MTT assay, colony formation assay and flow cytometry. Expression of Golgi phosphoprotein (GOLPH)3, β-catenin, GSK-3β and pS9-GSK-3β in cancer cells was determined by Western blotting.

Results: SW620 cells expressed the highest level of GOLPH3 mRNA, and the silence effect was good after they were transfected with siRNA-GOLPH3. The relative luminescence units (RLU) values in the experimental groups were significantly lower than in the negative control group (P<0.001). There was no significant difference in the RLU values among the experimental groups (P> 0.05). The growth inhibition ratio and apoptosis rate of cancer cells in each experimental group were significantly higher than those in the control group, and the cell colony count in the experimental group was significantly lower than in the control group (P<0.05). In addition, the RLU value, proliferation and apoptosis rate of cancer cells did not differ significantly between each two experimental groups. Western blotting showed that, compared with the control group, expression of β-catenin and pS9-GSK3 proteins were significantly decreased in the experimental group. Expression of GSK-3β in the experimental group did not different from that of the control group.

Conclusions: Overexpression of GOLPH3 gene activated the Wnt signaling pathway, as well as increasing expression of β-catenin, promoting proliferation and inhibiting apoptosis in human colon cancer cells. The mechanism of action was that overexpression of GOLPH3 gene activated Akt, which may also further activate the Wnt signaling pathway via GSK-3β, and promote proliferation in human colon cancer cells.

Distinct Biochemical Pools of Golgi Phosphoprotein 3 in the Human Breast Cancer Cell Lines MCF7 and MDA-MB-231

Golgi phosphoprotein 3 (GOLPH3) has been implicated in the development of carcinomas in many human tissues, and is currently considered a bona fide oncoprotein. Importantly, several tumor types show overexpression of GOLPH3, which is associated with tumor progress and poor prognosis. However, the underlying molecular mechanisms that connect GOLPH3 function with tumorigenicity are poorly understood. Experimental evidence shows that depletion of GOLPH3 abolishes transformation and proliferation of tumor cells in GOLPH3-overexpressing cell lines. Conversely, GOLPH3 overexpression drives transformation of primary cell lines and enhances mouse xenograft tumor growth in vivo. This evidence suggests that overexpression of GOLPH3 could result in distinct features of GOLPH3 in tumor cells compared to that of non-tumorigenic cells. GOLPH3 is a peripheral membrane protein mostly localized at the trans-Golgi network, and its association with Golgi membranes depends on binding to phosphatidylinositol-4-phosphate. GOLPH3 is also contained in a large cytosolic pool that rapidly exchanges with Golgi-associated pools. GOLPH3 has also been observed associated with vesicles and tubules arising from the Golgi, as well as other cellular compartments, and hence it has been implicated in several membrane trafficking events. Whether these and other features are typical to all different types of cells is unknown. Moreover, it remains undetermined how GOLPH3 acts as an oncoprotein at the Golgi. Therefore, to better understand the roles of GOLPH3 in cancer cells, we sought to compare some of its biochemical and cellular properties in the human breast cancer cell lines MCF7 and MDA-MB-231 with that of the non-tumorigenic breast human cell line MCF 10A. We found unexpected differences that support the notion that in different cancer cells, overexpression of GOLPH3 functions in diverse fashions, which may influence specific tumorigenic phenotypes.

Overexpression of GOLPH3 is associated with poor survival in Non-small-cell lung cancer

As a highly conserved protein of the Golgi apparatus, Golgi phosphoprotein 3 (GOLPH3) has been shown to be involved in tumorigenesis. This study aims to explore the expression and significance of GOLPH3 in non-small-cell lung cancer (NSCLC). We found that GOLPH3 expression was significantly elevated in NSCLC tissues when compared with adjacent lung tissues (p<0.01). Moreover, GOLPH3 expression was significantly associated with histological type (p<0.01), differentiation (p<0.01), and lymph node metastasis (p<0.05). Kaplan-Meier survival analysis showed that overall survival of patients with high expression of GOLPH3 was significantly shorter (n=100, p<0.05). In addition, GOLPH3 knock-down in two independent NSCLC cell lines inhibited cell viability through the induction of cell cycle arrest and apoptosis. In conclusion, GOLPH3 is closely related to the progression in NSCLC and could be served as a potential prognostic biomarker and therapeutic target for NSCLC.

Prognostic significance of EZH2 expression in patients with oesophageal cancer: a meta-analysis

Enhancer of zeste 2 (EZH2), a key component of polycomb repressive complex 2 (PRC2), was of great importance in human cancer pathogenesis. Various studies examined the relationship between EZH2 overexpression with the clinical outcome in patients with digestive cancers, but yielded conflicting results. Electronic databases updated to January 2015 were searched to find relevant studies. A meta‐analysis was conducted with eligible studies which quantitatively evaluated the relationship between EZH2 overexpression and survival of patients with digestive cancers. Survival data were aggregated and quantitatively analysed. We performed a meta‐analysis of 10 studies (n = 1461 patients) that evaluated the correlation between EZH2 overexpression and survival in patients with digestive cancers. Combined hazard ratios suggested that EZH2 overexpression was associated with poor prognosis of overall survival (HR = 1.54, 95% CI: 1.27–1.81) in patients with oesophageal cancer. In the stratified analysis, no significant risks were found among gastric cancer (HR = 0.66, 95% CI: 0.16–1.15) and colorectal cancer (HR = 0.91, 0.63–1.19), indicating that EZH2 was not an indicator of poor prognosis in gastric cancer or colorectal cancer. Enhancer of zeste 2 overexpression indicates a poor prognosis for patients with oesophageal cancer, but not among gastric cancer or colorectal cancer.

Correlational research of Golgi phosphorylation protein 3 expression in colorectal cancer

AIM

To investigate the effect of Golgi phosphorylation protein 3 (GOLPH3) expression on cell apoptosis, angiogenesis and prognosis in colorectal cancer (CRC).

METHODS

The expression of GOLPH3 in CRC tissues and normal colorectal mucosae was determined by immunohistochemistry in 62 patients. In addition, immunohistochemistry was also carried out to detect the expression of vascular endothelial growth factor (VEGF), CD34 and microvessel density (MVD). Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay was used to determine the apoptotic index (AI). The Kaplan-Meier method was used to analyze the relationship between GOLPH3 expression and survival in another 123 CRC cases.

RESULTS

Compared with normal colorectal mucosae, a notably higher level of GOLPH3 protein expression was identified in CRC tissues (53.2% vs 24.2%, P < 0.05). Positive GOLPH3 expression was significantly associated with tumor invasion depth, TNM stage, and lymph node metastasis (P = 0.001; P = 0.020; P = 0.020; P < 0.05, respectively), but not with tumor length, tumor site, and age (P = 0.363; P = 0.819; P = 0.599; P > 0.05, respectively). VEGF expression and MVD in GOLPH3-positive CRC was significantly higher than in GOLPH3-negative CRC (VEGF: 69.7% vs 31.0%; MVD: 21.45 ± 9.39 vs 14.24 ± 8.97; P < 0.05). GOLPH3 expression was negatively correlated with AI in CRC as shown by Spearman correlation analysis (r = -0.320, P < 0.05). The 5-year survival rate in GOLPH3-negative CRC (69.4%) was significantly higher than in GOLPH3-positive CRC (48.6%) (log-rank test, P < 0.05).

CONCLUSION

High expression of GOLPH3 is found in CRC tissues. GOLPH3 expression may be a novel prognostic marker for CRC patients.

GOLPH3 is a potential therapeutic target and a prognostic indicator of poor survival in bladder cancer treated by cystectomy

Golgi phosphoprotein 3 (GOLPH3) has been reported to be involved in the development of several human cancers. However, its clinical significance and biological role in bladder cancer remains unclear. In this study, we sought to analyze the GOLPH3 expression in bladder cancer samples and cells, and explore its clinical significance and biological role. We found that GOLPH3 was significantly increased in bladder cancer tissues and cells. Overexpression of GOLPH3 had significant correlation with poorer survival for bladder cancer patients treated by cystectomy. Knockdown of GOLPH3 inhibited the proliferation, migration and invasion of cancer cells, and tumor growth in a xenograft mouse model. GOLPH3 silencing inhibited AKT/m-TOR signaling, increased the cyclin-dependent kinase (CDK) inhibitor p27 and decreased the CDK regulator cyclin D1 and matrix metallopeptidase 9 (MMP9). Thus, GOLPH3 is likely to play important roles in bladder cancer progression via modulating AKT/mTOR signaling, and it is a novel prognostic biomarker and promising therapeutic target for bladder cancer.

The roles of the oncoprotein GOLPH3 in contractile ring assembly and membrane trafficking during cytokinesis

Cytokinesis is an intricate process that requires an intimate interplay between actomyosin ring constriction and plasma membrane remodelling at the cleavage furrow. However, the molecular mechanisms involved in coupling the cytoskeleton dynamics with vesicle trafficking during cytokinesis are poorly understood. The highly conserved Golgi phosphoprotein 3 (GOLPH3), functions as a phosphatidylinositol 4-phosphate (PI4P) effector at the Golgi. Recent studies have suggested that GOLPH3 is up-regulated in several cancers and is associated with poor prognosis and more aggressive tumours. In Drosophila melanogaster, GOLPH3 localizes at the cleavage furrow of dividing cells, is required for successful cytokinesis and acts as a key molecule in coupling phosphoinositide (PI) signalling with actomyosin ring dynamics. Because cytokinesis failures have been linked with pre-malignant disease and cancer, the novel connection between GOLPH3 and cytokinesis imposes new fields of investigation in cancer biology and therapy.

Prognostic significance of EZH2 expression in patients with digestive cancers: a meta-analysis

BACKGROUND

Enhancer of zeste 2 (EZH2), a key component of polycomb repressive complex 2 (PRC2), was of great importance in human cancer pathogenesis. Various studies examined the relationship between EZH2 overexpression with the clinical outcome in patients with digestive cancers, but yielded inconsistent results.

METHODS

Electronic databases updated to January 2015 were searched to find relevant studies. A meta-analysis was conducted with eligible studies which quantitatively evaluated the relationship between EZH2 overexpression and survival of patients with digestive cancers. Survival data were aggregated and quantitatively analyzed.

RESULTS

We performed a meta-analysis of 10 studies (n = 1,461 patients) that evaluated the correlation between EZH2 overexpression and survival in patients with digestive cancers. Combined hazard ratios suggested that EZH2 overexpression was associated with poor prognosis of overall survival (HR = 1.54, 95% CI: 1.27-1.81) in patients with esophageal cancer. In the stratified analysis, no significantly risks were found among gastric cancer (HR = 0.66, 95% CI: 0.16-1.15) and colorectal cancer (HR = 0.91, 0.63-1.19), indicating EZH2 was not an indicator of poor prognosis in gastric cancer or colorectal cancer.

CONCLUSIONS

EZH2 overexpression indicates a poor prognosis for patients with esophageal cancer, but not among gastric cancer or colorectal cancer.

Golgi phosphoprotein3 overexpression is associated with poor survival in patients with solid tumors: a meta-analysis

Golgi phosphoprotein3 (GOLPH3) is known as an oncoprotein and may be a prognostic biomarker in various tumors. Here we performed a meta-analysis on the association of GOLPH3 expression and survival in solid tumors. All eligible studies were identified in Embase, PubMed and Web of Science Databases up to November 2014. Data about overall survival (OS), and disease-free survival (DFS) were extracted and pooled hazard ratios (HRs) of GOLPH3 for survival were calculated by using a random-effect model. Heterogeneity and publication bias were also assessed. A total of 15 eligible studies which comprised of 2529 cases were included in this global analysis: 14 were dealing with overall survival (OS) and 6 were with disease-free survival (DFS). We found that GOLPH3 overexpression was associated with shorter OS (HR 2.487, 95% CI 1.897-3.258, P < 0.001) and DFS (HR 1.911, 95% CI 1.245-2.932, P = 0.003) in general carcinomas. Importantly, subgroup analysis suggested that overexpression of GOLPH3 correlated with shorter OS in urogenital system cancers (HR 4.258, 95% CI 1.81-4.91, P < 0.001). Moreover, publication bias was not significant (P > 0.05). In conclusion, the present meta-analysis showed that overexpression of GOLPH3 predicts poor prognosis in solid tumors.

Short interfering RNA directed against the GOLPH3 gene enhances the effect of chemotherapy against oral squamous cell carcinoma by regulating Caspase3, Bcl2 and cytochrome-c expression

Growing evidence reported that Golgi phosphoprotein 3 (GOLPH3) was involved in the progression of several human cancers. To determine whether knockout of GOLPH3 enhances the effect of Chemotherapy against cell growth of oral squamous cell carcinoma in vitro. OSCC cells were transfected with Golph3 plasmid, Golph3-RNAi and the relative control plasmids. Transfected Tca-8113 cells treated with cis-Dichlorodiamineplatinum (DDP; 0, 0.05, 0.25, 1.25, 6.25 and 31.25 ug/ml) or Paclitaxe (0, 2, 10, 50, 250 and 1250 nM) or Adriamycin (0, 0.25, 0.5, 1, 2 and 4 ug/ml) for 24 h, respectively, was determined using MTT assay. Apoptosis-related protein expression Cytochrome-C, Caspase3 and Bcl-2 was analyzed by RT-PCR and western blots. Result of MTT showed that Golph3-RNAi transfected Tca-8113 cells enhanced the effect of chemotherapy, and the effect was strengthened with the increasing concentration of drugs, and the Golph3 plasmid transfected Tca-8113 cells showed the opposite effect. RT-PCR and western blots assays revealed that expression of cytochrome-C and caspase3 were up-regulated, while Bcl-2 expression was down-regulated in Golph3-RNAi transfected Tca-8113 cells. Taken together, this study demonstrated that GOLPH3 had potent pro-tumor growth and decreased the effect of Chemotherapy, and its mechanism is primarily via cell anti-apoptosis, down-regulating the expression of cytochrome-C and caspase3, up-regulating Bcl-2 expression.

GOLPH3L is a Novel Prognostic Biomarker for Epithelial Ovarian Cancer

OBJECTIVE

Golgi phosphoprotein 3 (GOLPH3) is a highly conserved membrane protein that is involved in a variety of cancers such as colorectal cancer, gastric cancer, ovarian cancer, and breast cancer. GOLPH3L is a paralog of GOLPH3. Although these proteins share a similar amino acid sequence, much less is known regarding the subcellular functions or effects of GOLPH3L on cancer compared with GOLPH3. The role of GOLPH3L in epithelial ovarian cancer (EOC) has not yet been investigated.

METHODS

Using western blot, PCR and immunohistochemical analyses, we studied the clinical significance of GOLPH3L expression in EOC. The correlations between GOLPH3L expression and the clinicopathological variables of patients with EOC were assessed using Pearson's χ2 test. Kaplan-Meier analysis was used to compare the postoperative survival between groups of patients with EOC with varying levels of GOLPH3L expression.

RESULTS

High expression of GOLPH3L was more frequently observed in EOC tissues than in corresponding adjacent non-tumor tissues. The expression of GOLPH3L correlated closely with pre-operative CA125 level (P=0.031). Univariate analysis showed that age, FIGO stage, pre-operative cancer antigen (CA) 125, pre-operative albumin concentration (AC), optimal cytoreductive surgery (CRS) and GOLPH3L expression correlate significantly with overall survival (OS). Multivariate analysis revealed that GOLPH3L expression was an independent prognostic factor for OS of patients with EOC (102 months versus 72 months; P=0.013). What's more, knocked down of GOLPH3L with small interfering RNA (siRNA) technology of OVCAR3 and SKOV3 cell lines reduced cell viability obviously, compared to the negative control and blank control groups.

CONCLUSIONS

Our data show that increased expression of GOLPH3L is associated with poor prognosis of patients with EOC and may act as a novel, useful and independent prognostic indicator. Therefore, further studies are warranted.

Prognostic value of long noncoding RNA HOTAIR in digestive system malignancies

BACKGROUND AND AIM

HOX transcript antisense intergenic RNA (HOTAIR), a well-known long noncoding RNA, has been found to play significant roles in several tumors. However, the clinical application value of HOTAIR in digestive system malignancies remains to be clarified. We aimed to explore comprehensively the potential role of HOTAIR as a prognostic indicator in digestive system malignancies.

METHODS

Systematic search was performed in Pubmed, Embase, Cochrane Library, and Web of Science until July 5, 2014. A quantitative meta-analysis was conducted with standard statistical methods for eligible papers on the prognostic value of HOTAIR in digestive system cancers.

RESULTS

A total of 1059 patients from 13 studies were included in the meta-analysis. A significant association was found between HOTAIR abundance and poor overall survival (OS) of patients with digestive system malignancies, with pooled hazard ratio (HR) of 2.587 (95% confidence interval [CI]: 2.054-3.259, P < 0.001). By combining HRs from Cox multivariate analyses, we found HOTAIR was an independent prognostic factor for OS without obvious heterogeneity (HR: 2.405, 95% CI: 1.883-3.0722, P < 0.001). Subgroup analysis showed that tumor type, histology type, region, publication year, sample size, and quality score did not alter the predictive value of HOTAIR as an independent factor for survival. Meta-regression and sensitivity analysis both suggested the reliability of our findings. A slight publication bias was observed. After adjustment by nonparametric "trim-and-fill" method, the corrected HRs had no significant change.

CONCLUSION

HOTAIR could be exploited as a novel prognostic biomarker for patients with digestive system malignancies.

GOLPH3, a good prognostic indicator in early-stage NSCLC related to tumor angiogenesis

BACKGROUND

Golgi phosphoprotein-3 (GOLPH3) is implicated in cancer development and progression. The aim of this study was to evaluate the prognostic significance of GOLPH3 protein and its association with tumor angiogenesis in patients with early-stage NSCLC.

MATERIALS AND METHODS

Immunohistochemistry was performed to determine GOLPH3 protein expression and allow assessment of intratumoral microvessel density (MVD) by counting CD-34 positive immunostained endothelial cells. Correlations of expression with MVD, clinicopathologic features and clinical prognosis were analyzed.

RESULTS

A notably higher level of GOLPH3 expression was found in early-stage NSCC tissues at the protein level. However, we do not find any correlation between GOLPH3 expression and clinicopathologic features (p>0.05), although higher MVD was positively associated with GOLPH3 overexpression (p<0.001). Expression of GOLPH3 was found to be an independent prognostic factor in early- stage NSCLC patients, those expressing high levels of GOLPH3 exhibiting a substantially lower 5-year overall survival than GOLPH3-negative patients (adjusted HR =1.899, 95% CI: 1.021-3.532, p=0.043).

CONCLUSIONS

High expression of the GOLPH3 protein is common in early-stage NSCC, and is closely associated with tumor progression, increased tumor angiogenesis, and poor survival. We conclude a possibility of its use as a diagnostic and prognostic marker in early-stage NSCC patients.

Golgi phosphoprotein 3 regulates metastasis of prostate cancer via matrix metalloproteinase 9

Recent studies suggest that Golgi phosphoprotein 3 (GOLPH3) protein is a candidate metastasis gene in human cancer. The goal of this study was to determine the function of GOLPH3 in prostate cancer metastasis and to identify GOLPH3-regulated pathways and genes involved in prostate cancer metastasis. GOLPH3 expression was detected in prostate cancer. To investigate its function, PC-3 cells were stably transfected with shRNA targeting GOLPH3. Cell abilities of invasion and migration were measured in vitro. Downstream regulatory pathways of GOLPH3 were characterized using quantitative RT-PCR and Western blotting analysis. Immunohistochemical studies in prostate cancer specimens revealed a positive correlation of GOLPH3 expression with prostate cancer. GOLPH3 was expressed in prostate cancer cell lines. GOLPH3 repression resulted in the reduction of mRNA level and protein level of MMP9, accompanied with reduced phosphorylation of mTOR, EGFR and Src. Our findings suggest GOLPH3 regulate MMP9 expression which impact cell migration and invasion. This regulation is probably mediated by EGFR and Src signaling pathways.

Golgi phosphoprotein 3 expression predicts poor prognosis in patients with prostate cancer undergoing radical prostatectomy

Golgi phosphoprotein 3 (GOLPH3) has recently been implicated as an oncogene involved in the development of carcinoma in a number of organs. The expression of GOLPH3 in prostate cancer (PCa) tissues was investigated in the present study. Human PC-3 and LNCaP PCa cell lines were analyzed in order to assess whether silencing of GOLPH3 expression affects cell vitality, migration and invasion, in vitro. An immunohistochemistry analysis was performed in order to measure the expression of GOLPH3 in samples from 117 patients with PCa and from 50 patients with benign prostatic hyperplasia (BPH). Associations between GOLPH3 expression and clinicopathological parameters, such as overall survival, were assessed. GOLPH3 expression was shown to be significantly greater in PCa tissues than in BPH tissues. GOLPH3 expression was positively correlated with Gleason score (P=0.031), tumor stage (T stage; P=0.020) and lymph node status (P=0.013), in patients with PCa. Biochemical recurrence-free survival (serum prostate-specific antigen-based) and overall survival, were reduced in patients with GOLPH3-positive PCa. A multivariate analysis indicated that GOLPH3 expression was an independent predictor of biochemical recurrence-free survival [hazard ratio (HR), 2.943; 95% confidence interval (CI), 1.190-5.521; P=0.028], and of overall survival (HR, 4.371; 95% CI, 2.045-7.109; P=0.014). Transfection with GOLPH3‑targeted small interfering RNA reduced the capability of PC-3 and LNCaP cell lines to proliferate, migrate and invade in vitro, compared with the controls. The level of GOLPH3 expression in radical prostatectomy samples may be useful for predicting biochemical recurrence-free survival and overall survival in patients with PCa.

The multiple cellular functions of the oncoprotein Golgi phosphoprotein 3

The highly conserved Golgi phosphoprotein 3 (GOLPH3) protein, a component of Trans-Golgi Network (TGN), has been defined as a "first-in-class Golgi oncoprotein" and characterized as a Phosphatidylinositol 4-phosphate [PI(4)P] effector at the Golgi. GOLPH3 is commonly amplified in several solid tumors. Furthermore this protein has been associated with poor prognosis in many cancers. Highly conserved from yeast to humans, GOLPH3 provides an essential function in vesicle trafficking and Golgi structure. Recent data have also implicated this oncoprotein in regulation of cytokinesis, modulation of mitochondrial mass and cellular response to DNA damage. A minute dissection of the molecular pathways that require GOLPH3 protein will be helpful to develop new therapeutic cancer strategies.

An oncogenic protein Golgi phosphoprotein 3 up-regulates cell migration via sialylation

Recently, the Golgi phosphoprotein 3 (GOLPH3) and its yeast homolog Vps74p have been characterized as essential for the Golgi localization of glycosyltransferase in yeast. GOLPH3 has been identified as a new oncogene that is commonly amplified in human cancers to modulate mammalian target of rapamycin signaling. However, the molecular mechanisms of the carcinogenic signaling pathway remain largely unclear. To investigate whether the expression of GOLPH3 was involved in the glycosylation processes in mammalian cells, and whether it affected cell behavior, we performed a loss-of-function study. Cell migration was suppressed in GOLPH3 knockdown (KD) cells, and the suppression was restored by a re-introduction of the GOLPH3 gene. HPLC and LC/MS analysis showed that the sialylation of N-glycans was specifically decreased in KD cells. The specific interaction between sialyltransferases and GOLPH3 was important for the sialylation. Furthermore, overexpression of α2,6-sialyltransferase-I rescued cell migration and cellular signaling, both of which were blocked in GOLPH3 knockdown cells. These results are the first direct demonstration of the role of GOLPH3 in N-glycosylation to regulate cell biological functions.

GOLPH3 links the Golgi, DNA damage, and cancer

GOLPH3 is the first example of an oncogene that functions in secretory trafficking at the Golgi. The discovery of GOLPH3's roles in both cancer and Golgi trafficking raises questions about how GOLPH3 and the Golgi contribute to cancer. Our recent investigation of the regulation of GOLPH3 revealed a surprising response by the Golgi upon DNA damage that is mediated by DNA-PK and GOLPH3. These results provide new insight into the DNA damage response with important implications for understanding the cellular response to standard cancer therapeutic agents.

High GOLPH3 expression is associated with poor prognosis and invasion of hepatocellular carcinoma

Golgi phosphoprotein 3 (GOLPH3) overexpression has previously been associated with the progression of several solid tumors, which resulted in adverse clinical outcomes. The present study aimed to determine the expression and prognostic significance of GOLPH3 in human hepatocellular carcinoma (HCC). GOLPH3 expression was examined using western blot analysis of 30 paired samples of HCC and adjacent non‑cancerous liver tissues. GOLPH3 expression levels were also assessed using immunohistochemistry in 180 HCC samples and paired controls. In addition, the association of GOLPH3 expression with clinicopathological features and clinical outcome was analyzed. Furthermore, the effect of GOLPH3 on HCC cell proliferation and invasion were determined. Western blot analysis revealed that GOLPH3 expression was significantly elevated in HCC tissue compared with that of the matched adjacent non‑cancerous liver tissue. In addition, the results of the immunohistochemical analysis demonstrated that GOLPH3 expression was positively correlated with the Edmondson‑Steiner grade (P=0.006), vascular invasion (P=0.002) and serum α feto‑protein levels (P=0.015). GOLPH3 expression was found to be an independent factor for predicting the poor overall survival of HCC patients (hazard ratio, 2.01; 95% confidence interval, 1.26‑3.64; P=0.025). In addition, GOLPH3 silencing inhibited the proliferation, invasion and migration of HCC cell lines in vitro. In conclusion, the results of the present study demonstrated that high GOLPH3 levels may be a potential biomarker for the poor prognosis of patients with HCC.

Golgi phosphoprotein 3 triggers signal-mediated incorporation of glycosyltransferases into coatomer-coated (COPI) vesicles

Newly synthesized membrane and secreted proteins undergo a series of posttranslational modifications in the Golgi apparatus, including attachment of carbohydrate moieties. The final structure of so-formed glycans is determined by the order of execution of the different glycosylation steps, which seems intimately related to the spatial distribution of glycosyltransferases and glycosyl hydrolases within the Golgi apparatus. How cells achieve an accurate localization of these enzymes is not completely understood but might involve dynamic processes such as coatomer-coated (COPI) vesicle-mediated trafficking. In yeast, this transport is likely to be regulated by vacuolar protein sorting 74 (Vps74p), a peripheral Golgi protein able to interact with COPI coat as well as with a binding motif present in the cytosolic tails of some mannosyltransferases. Recently, Golgi phosphoprotein 3 (GOLPH3), the mammalian homolog of Vps74, has been shown to control the Golgi localization of core 2 N-acetylglucosamine-transferase 1. Here, we highlight a role of GOLPH3 in the spatial localization of α-2,6-sialyltransferase 1. We show, for the first time, that GOLPH3 supports incorporation of both core 2 N-acetylglucosamine-transferase 1 and α-2,6-sialyltransferase 1 into COPI vesicles. Depletion of GOLPH3 altered the subcellular localization of these enzymes. In contrast, galactosyltransferase, an enzyme that does not interact with GOLPH3, was neither incorporated into COPI vesicles nor was dependent on GOLPH3 for proper localization.

Mechanisms of GOLPH3 associated with the progression of gastric cancer: a preliminary study

Study Design

To investigate the specific mechanisms by which Golgi phosphoprotein 3 (GOLPH3) affects the progression of gastric cancer and to explore its clinical significance.

Methods

Immunohistochemical analysis was used to evaluate the correlations between GOLPH3, phosphorylated mTOR (p-mTOR), phosphorylated Akt (p-Akt), phosphorylated p70S6 (p-p70S6), phosphorylated 4E-BP1 (p-4E-BP1) and the clinicopathological features of gastric cancer. The mRNA expression levels of GOLPH3, mTOR, Akt, p70S6 and 4E-BP1 in gastric cancer, carcinoma-adjacent and paired normal tissue were analyzed using RT-PCR. Western blotting was used to determine the protein expression of GOLPH3, p-mTOR, p-Akt, p-p70S6 and p-4E-BP1 in tissues.

Results

High expression protein levels of GOLPH3, p-AKT, p-mTOR, p70S6, p-4E-BP1 were positively associated with histological grade (p<0.05), depth of invasion (p<0.05), distant metastasis (p<0.05) and lymph node involvement (p<0.05). Compared with carcinoma-adjacent and paired normal tissues, the mRNA expression levels of GOLPH3, AKT, mTOR, p70S6 and 4EBP1 in gastric cancer tissues were significantly higher. The protein expression levels of GOLPH3, p-AKT, p-mTOR, p-p70S6 and p-4E-BP1 in gastric cancer tissues were also significantly higher than in carcinoma-adjacent and paired normal tissues. A strong positive correlation was observed between GOLPH3, p-mTOR, p-p70S6 and p-4EBP1 expression (r = 0.410, 0.303 and 0.276, respectively, p<0.05), but no significant correlation between the expression of GOLPH3 and p-Akt was observed.

Conclusions

The GOPLH3 expression level is highly correlated with Akt/mTOR signaling in human gastric cancer samples. GOLPH3 combined with Akt/mTOR signaling activation may play an important role in the development, differentiation, invasion and metastasis of gastric cancer.

Overexpression of GOLPH3 is associated with poor prognosis and clinical progression in pancreatic ductal adenocarcinoma

Background

Golgi phosphoprotein 3 (GOLPH3) has been identified as an oncoprotein in various human cancers; however, its role in pancreatic ductal adenocarcinoma (PDAC) is unknown. We examined GOLPH3 expression levels and relationship with survival in patients with PDAC to establish the significance of GOLPH3 in the development and progression of PDAC.

Methods

Real-time qPCR and Western blotting were performed to analyze the expression levels of GOLPH3 mRNA and protein in paired PDAC tumor and adjacent non-tumor tissues. Immunohistochemistry was used to analyze the expression levels of GOLPH3 protein in paraffin-embedded tissues from 109 cases of PDAC. Univariate and multivariate analyses were performed to identify correlations between the immunohistochemical data for GOLPH3 expression and the clinicopathologic characteristics in PDAC.

Results

Expression levels of GOLPH3 mRNA and protein were upregulated in PDAC lesions compared to paired adjacent noncancerous tissues. Expression of GOLPH3 was significantly correlated with clinical stage (P = 0.006), T classification (P = 0.021), N classification (P = 0.049) and liver metastasis (P = 0.035). Patients with high GOLPH3 expression had shorter overall survival times compared to those with low GOLPH3 expression (P = 0.007). Multivariate analysis revealed that GOLPH3 overexpression was an independent prognostic factor in PDAC.

Conclusions

Our findings suggest that GOLPH3 expression status may be a potential prognostic biomarker and therapeutic target in PCAC.

GOLPH3 high expression predicts poor prognosis in patients with resected non-small cell lung cancer: an immunohistochemical analysis

Golgi phosphoprotein 3 (GOLPH3) has been reported to be involved in the development of several human tumours. However, little is known about GOLPH3 expression and its clinical significance in non-small cell lung cancer (NSCLC). The present study was conducted to investigate the expression of GOLPH3 and its prognostic significance in NSCLC. Immunohistochemical analysis was used to determine the expression of GOLPH3 in 145 cases NSCLC tissue and their corresponding adjacent normal tissues. The results are the following: (1) The GOLPH3 protein was mainly located in the cytoplasm of NSCLC tissue; (2) GOLPH3 was highly expressed in 71.7% of NSCLC tissues versus 22.8% of adjacent tissues (P < 0.01); (3) GOLPH3 expression was significantly associated with tumour-node-metastasis (TNM) stage (P = 0.001), lymph node status (P = 0.014), and degree of differentiation (P = 0.018); (4) The Kaplan-Meier curve indicated that the patients with high GOLPH3 expression had significantly shorter survival than those with low GOLPH3 expression; and (5) Cox regression analysis demonstrated that the expression of GOLPH3, lymph node status, and TNM stage were independent prognostic predictors for NSCLC patients. High GOLPH3 expression is predictive of poor prognosis of NSCLC, implying that GOLPH3 may be a promising new target for targeted therapies for NSCLC.

Insulin receptor substrate-1 and Golgi phosphoprotein 3 are downstream targets of miR‑126 in esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is a common histologic subtype in China. It has been suggested that abnormal expression of microRNAs (miRNAs) is associated with carcinogenesis. We investigated miR-126 expression and its potential targets in ESCC. The expression of miR-126 was detected in cancerous and paired paracancer tissues from 102 patients with ESCC. Target analysis of miR-126 was predicted using online tools. The effect of miR-126 expression on target proteins was assessed using miR-126 mimics or miR-126 inhibitors in ESCC cell lines. In addition, the impact of miR-126 on cell proliferation, apoptosis, migration and invasion was detected in ESCC cell lines. The expression of miR-126 was significantly lower in ESCC tissues, which was associated with tumor differentiation, lymph node metastasis, tumor in-depth and TNM stage. Insulin receptor substrate-1 (IRS-1) and Golgi phosphoprotein 3 (GOLPH3) were overexpressed in ESCC. Overexpression of IRS-1 was associated with cell differentiation, whereas GOLPH3 was related to lymph node metastasis, tumor invasion in-depth and TNM stage in ESCC patients. miR-126 mimics downregulated the expression of IRS-1 and GOLPH3 protein and suppressed the proliferation, migration and invasion of ESCC cells, whereas miR-126 inhibitors led to the opposite results. miR-126 suppressed the proliferation, migration and invasion of ESCC cells, and acted as a tumor suppressor in the carcinogenesis of ESCC. IRS-1 and GOLPH3 are downstream targets of miR-126 at the post-transcriptional level in ESCC.

Structural genomic variation as risk factor for idiopathic recurrent miscarriage

Recurrent miscarriage (RM) is a multifactorial disorder with acknowledged genetic heritability that affects ∼3% of couples aiming at childbirth. As copy number variants (CNVs) have been shown to contribute to reproductive disease susceptibility, we aimed to describe genome-wide profile of CNVs and identify common rearrangements modulating risk to RM. Genome-wide screening of Estonian RM patients and fertile controls identified excessive cumulative burden of CNVs (5.4 and 6.1 Mb per genome) in two RM cases possibly increasing their individual disease risk. Functional profiling of all rearranged genes within RM study group revealed significant enrichment of loci related to innate immunity and immunoregulatory pathways essential for immune tolerance at fetomaternal interface. As a major finding, we report a multicopy duplication (61.6 kb) at 5p13.3 conferring increased maternal risk to RM in Estonia and Denmark (meta-analysis, n = 309/205, odds ratio = 4.82, P = 0.012). Comparison to Estonian population-based cohort (total, n = 1000) confirmed the risk for Estonian female cases (P = 7.9 × 10(-4) ). Datasets of four cohorts from the Database of Genomic Variants (total, n = 5,846 subjects) exhibited similar low duplication prevalence worldwide (0.7%-1.2%) compared to RM cases of this study (6.6%-7.5%). The CNV disrupts PDZD2 and GOLPH3 genes predominantly expressed in placenta and it may represent a novel risk factor for pregnancy complications.

Lentivirus mediated GOLPH3 shRNA inhibits growth and metastasis of esophageal squamous cancer

AIM

To investigate the role of Golgi phosphoprotein 3 (GOLPH3) in tumour growth and metastasis of esophageal squamous cancer.

METHODS

A lentiviral shRNA-vector was utilized to stably knockdown GOLPH3 in Eca-109 esophageal squamous cancer cells. mRNA transcription and protein expression of GOLPH3 were examined by real-time quantitative PCR and Western blotting, respectively. Cell proliferation activity was assessed by MTT assay and invasion and migration potentials by matrigel invasion and transwell motility assays.

RESULTS

Stable knockdown in the GOLPH3 cell line was established. PD-A gene expression was significantly suppressed by lentivirus-mediated RNAi, which resulted in reducing the capacity for cell proliferation, migration, invasion and adhesion in vitro. In vivo, GOLPH3 depletion resulted in inhibition of tumour growth, with stable decrease in the expression of GOLPH3 in tumor xenografts.

CONCLUSIONS

Our findings suggest that lentivirus mediated silencing of the GOLPH3 gene has a significant anti-tumour effect on esophageal squamous cancer in vitro and in vivo. In addition, the results indicate that GOLPH3 might be an effective molecular target for gene therapy in esophageal squamous cancer.

GOLPH3 is essential for contractile ring formation and Rab11 localization to the cleavage site during cytokinesis in Drosophila melanogaster

The highly conserved Golgi phosphoprotein 3 (GOLPH3) protein has been described as a Phosphatidylinositol 4-phosphate [PI(4)P] effector at the Golgi. GOLPH3 is also known as a potent oncogene, commonly amplified in several human tumors. However, the molecular pathways through which the oncoprotein GOLPH3 acts in malignant transformation are largely unknown. GOLPH3 has never been involved in cytokinesis. Here, we characterize the Drosophila melanogaster homologue of human GOLPH3 during cell division. We show that GOLPH3 accumulates at the cleavage furrow and is required for successful cytokinesis in Drosophila spermatocytes and larval neuroblasts. In premeiotic spermatocytes GOLPH3 protein is required for maintaining the organization of Golgi stacks. In dividing spermatocytes GOLPH3 is essential for both contractile ring and central spindle formation during cytokinesis. Wild type function of GOLPH3 enables maintenance of centralspindlin and Rho1 at cell equator and stabilization of Myosin II and Septin rings. We demonstrate that the molecular mechanism underlying GOLPH3 function in cytokinesis is strictly dependent on the ability of this protein to interact with PI(4)P. Mutations that abolish PI(4)P binding impair recruitment of GOLPH3 to both the Golgi and the cleavage furrow. Moreover telophase cells from mutants with defective GOLPH3-PI(4)P interaction fail to accumulate PI(4)P-and Rab11-associated secretory organelles at the cleavage site. Finally, we show that GOLPH3 protein interacts with components of both cytokinesis and membrane trafficking machineries in Drosophila cells. Based on these results we propose that GOLPH3 acts as a key molecule to coordinate phosphoinositide signaling with actomyosin dynamics and vesicle trafficking during cytokinesis. Because cytokinesis failures have been associated with premalignant disease and cancer, our studies suggest novel insight into molecular circuits involving the oncogene GOLPH3 in cytokinesis.

In animal cell cytokinesis, constriction of an actomyosin ring at the equatorial cortex of dividing cells must be finely coordinated with plasma membrane remodeling and vesicle trafficking at the cleavage furrow. Accurate control of these events during cell cleavage is essential for maintaining ploidy and preventing neoplastic transformation. GOLPH3 has been recognized as a potent oncogene, involved in the development of several human tumors. However, the precise roles played by GOLPH3 in tumorigenesis are not yet understood. In this manuscript we demonstrate for the first time the requirement for GOLPH3 for cytokinesis. GOLPH3 protein localizes at the cleavage site of Drosophila dividing cells and is essential for cytokinesis in male meiotic cells and larval neuroblasts. We show that this protein acts as a key molecule in coupling plasma membrane remodeling with actomyosin ring assembly and stability during cytokinesis. Our studies indicate a novel connection between GOLPH3 and the molecular mechanisms of cytokinesis, opening new fields of investigation into the tumor cell biology of this oncogene.

GOLPH3 gene overexpression promotes proliferation of gastric cancer cells

AIM: To observe the effect of GOLPH3 gene overexpression on the proliferation of gastric cancer cells.

METHODS: The lentivirus containing the GOLPH3 gene was infected into gastric cancer cells, fluorescence microscopy was used to detect the expression of EGFP, and flow cytometry was applied to verify the infection efficiency. GOLPH3 overexpression was verified by quantitative real-time PCR (at the mRNA level) and Western blot (at the protein level). The expression of mTOR and p-mTOR proteins was detected by Western blot, and cell proliferation was assessed by MTT assay.

RESULTS: Gastric cancer cells expressing high levels of EGFP were successfully obtained, with an infection rate of 100%. GOLPH3 expression was significantly up-regulated in SGC-7901 cells infected with the lentivirus containing the GOLPH3 gene compared with SGC-7901 cells transduced with the empty vector or non-infected SGC-7901 cells (P < 0.05 for both). MTT assay showed that up-regulated GOLPH3 could significantly enhance the proliferation of gastric cancer cells (P < 0.05). Although the mTOR protein expression did not significantly differ between different groups of cells, but p-mTOR protein expression was enhanced in SGC-7901 cells infected with the lentivirus containing the GOLPH3 gene compared with control cells (P < 0.05), suggesting that up-regulated GOLPH3 could promote the protein expression of p-mTOR in SGC-7901 cells.

CONCLUSION: GOLPH3 gene overexpression could promote the proliferation of gastric cancer cells by up-regulating the expression of p-mTOR in SGC-7901 cells.

DNA damage triggers Golgi dispersal via DNA-PK and GOLPH3

The response to DNA damage, which regulates nuclear processes such as DNA repair, transcription, and cell cycle, has been studied thoroughly. However, the cytoplasmic response to DNA damage is poorly understood. Here, we demonstrate that DNA damage triggers dramatic reorganization of the Golgi, resulting in its dispersal throughout the cytoplasm. We further show that DNA-damage-induced Golgi dispersal requires GOLPH3/MYO18A/F-actin and the DNA damage protein kinase, DNA-PK. In response to DNA damage, DNA-PK phosphorylates GOLPH3, resulting in increased interaction with MYO18A, which applies a tensile force to the Golgi. Interference with the Golgi DNA damage response by depletion of DNA-PK, GOLPH3, or MYO18A reduces survival after DNA damage, whereas overexpression of GOLPH3, as is observed frequently in human cancers, confers resistance to killing by DNA-damaging agents. Identification of the DNA-damage-induced Golgi response reveals an unexpected pathway through DNA-PK, GOLPH3, and MYO18A that regulates cell survival following DNA damage.

GOLPH3 is a novel marker of poor prognosis and a potential therapeutic target in human renal cell carcinoma

Background:

Golgi phosphoprotein 3 (GOLPH3) has been reported to be involved in the development of several human cancers. The present study was conducted to investigate the expression of GOLPH3 and its prognostic significance in renal cell carcinoma (RCC). Meanwhile, the function of GOLPH3 in human RCC was further investigated in cell culture models.

Methods:

Expression of GOLPH3 was examined in 43 fresh RCC tissues and paired adjacent normal renal tissues by real-time quantitative PCR and western blotting. Immunohistochemistry for GOLPH3 was performed on additional 218 RCC tissues. The clinical significance of GOLPH3 expression was analysed. Downregulation of GOLPH3 was performed using small-interfering RNA (siRNA) in Caki-1 and 786-O cells with high abundance of GOLPH3, and the effects of GOLPH3 silencing on cell proliferation, migration, invasion in vitro, and tumour growth in vivo were evaluated.

Results:

Expression of GOLPH3 was upregulated in the majority of the RCC clinical tissue specimens at both mRNA and protein levels. Clinicopathological analysis showed that GOLPH3 expression was significantly correlated with T stage (P<0.001), lymph-node status (P=0.003), distant metastasis (P<0.001), tumour-node-metastasis (TNM) stage (P<0.001), and Fuhman grade (P=0.001). Expression of GOLPH3 was inversely correlated with both overall and recurrence-free survival of RCC patients. Multivariate analysis showed that GOLPH3 expression was an independent prognostic indicator for patient's survival. Knockdown of the GOLPH3 expression reduced cell proliferation, anchorage-independent growth, migration, invasion, and tumour growth in xenograft model mice.

Conclusions:

These results suggest that GOLPH3 expression is likely to have important roles in RCC development and progression, and that GOLPH3 is a prognostic biomarker and a promising therapeutic target for RCC.

High GOLPH3 expression is associated with a more aggressive behavior of epithelial ovarian carcinoma

Overexpression of GOLPH3 (Golgi phosphoprotein 3, 34 kDa) is associated with the progression of many solid tumor types leading to an unfavorable clinical outcome. The present study examined the association between GOLPH3 expression and tumor development, clinicopathological factors, and prognosis of epithelial ovarian carcinoma. GOLPH3 expression was examined by immunohistochemistry in 18 normal ovarian samples, 28 benign tumors, 55 serous borderline ovarian tumors, and 135 epithelial ovarian carcinomas. The association of GOLPH3 expression with clinical characteristics, response to chemotherapy, and overall survival of epithelial ovarian carcinoma patients was analyzed on fresh tissue samples. GOLPH3 mRNA and protein expression in ovarian cancer and normal ovarian tissues were detected by real-time quantitative RT-PCR and Western blotting, respectively. The results are the following: (1) GOLPH3 immunostaining localized to the cytoplasm in two patterns, condensed into large granules with perinuclear distribution, and dispersed in the cytoplasm as fine granules. (2) GOLPH3 expression was higher in epithelial ovarian carcinoma than in normal ovarian tissues at the mRNA and protein level. The frequency of high-level expression of GOLPH3 increased progressively from benign (cystadenoma) to borderline neoplasms to malignant lesions. (3) Dispersed cytoplasmic GOLPH3 expression in epithelial ovarian carcinoma patients was highly correlated with FIGO stage (p < 0.001), tumor histological grade (p = 0.003), lymph node involvement (p = 0.001), and chemotherapy response (p = 0.034). (4) A dispersed pattern of GOLPH3 expression was an independent prognostic factor for poor overall survival. Patients with low dispersed cytoplasmic GOLPH3 expression had significantly longer overall survival than patients with high dispersed cytoplasmic expression. In contrast, GOLPH3 condensed expression was not correlated with clinicopathological features, chemotherapy response, or prognosis. GOLPH3 gene expression might play a role in tumorigenesis in epithelial ovarian carcinoma as upregulation of GOLPH3 expression is associated with a more aggressive tumor phenotype. GOLPH3 immunohistochemistry may be of value to predict the outcome of ovarian carcinoma patients.

GOLPH3 predicts survival of colorectal cancer patients treated with 5-fluorouracil-based adjuvant chemotherapy

Background

Golgi phosphoprotein 3 (GOLPH3) has been validated as a potent oncogene involved in the progression of many types of solid tumors, and its overexpression is associated with poor clinical outcome in many cancers. However, it is still unknown the association of GOLPH3 expression with the prognosis of colorectal cancer (CRC) patients who received 5-fluorouracil (5-FU)-based adjuvant chemotherapy.

Methods

The expression of GOLPH3 was determined by qRT-PCR and immunohistochemistry in colorectal tissues from CRC patients treated with 5-FU based adjuvant chemotherapy after surgery. The association of GOLPH3 with clinicopathologic features and prognosis was analysed. The effects of GOLPH3 on 5-FU sensitivity were examined in CRC cell lines.

Results

GOLPH3 expression was elevated in CRC tissues compared with matched adjacent noncancerous tissues. Kaplan-Meier survival curves indicated that high GOLPH3 expression was significantly associated with prolonged disease-free survival (DFS, P = 0.002) and overall survival (OS, P = 0.011) in patients who received 5-FU-based adjuvant chemotherapy. Moreover, multivariate analysis showed that GOLPH3 expression was an independent prognostic factor for DFS in CRC patients treated with 5-FU-based chemotherapy (HR, 0.468; 95%CI, 0.222-0.987; P = 0.046). In vitro, overexpression of GOLPH3 facilitated the 5-FU chemosensitivity in CRC cells; while siRNA-mediated knockdown of GOLPH3 reduced the sensitivity of CRC cells to 5-FU-induced apoptosis.

Conclusions

Our results suggest that GOLPH3 is associated with prognosis in CRC patients treated with postoperative 5-FU-based adjuvant chemotherapy, and may serve as a potential indicator to predict 5-FU chemosensitivity.