GOLPH3L is a Novel Prognostic Biomarker for Epithelial Ovarian Cancer

Independent duplications of the Golgi phosphoprotein 3 oncogene in birds

Golgi phosphoprotein 3 (GOLPH3) was the first reported oncoprotein of the Golgi apparatus. It was identified as an evolutionarily conserved protein upon its discovery about 20 years ago, but its function remains puzzling in normal and cancer cells. The GOLPH3 gene is part of a group of genes that also includes the GOLPH3L gene. Because cancer has deep roots in multicellular evolution, studying the evolution of the GOLPH3 gene family in non-model species represents an opportunity to identify new model systems that could help better understand the biology behind this group of genes. The main goal of this study is to explore the evolution of the GOLPH3 gene family in birds as a starting point to understand the evolutionary history of this oncoprotein. We identified a repertoire of three GOLPH3 genes in birds. We found duplicated copies of the GOLPH3 gene in all main groups of birds other than paleognaths, and a single copy of the GOLPH3L gene. We suggest there were at least three independent origins for GOLPH3 duplicates. Amino acid divergence estimates show that most of the variation is located in the N-terminal region of the protein. Our transcript abundance estimations show that one paralog is highly and ubiquitously expressed, and the others were variable. Our results are an example of the significance of understanding the evolution of the GOLPH3 gene family, especially for unraveling its structural and functional attributes.

A Density Peak-Based Method to Detect Copy Number Variations From Next-Generation Sequencing Data

Copy number variation (CNV) is a common type of structural variations in human genome and confers biological meanings to human complex diseases. Detection of CNVs is an important step for a systematic analysis of CNVs in medical research of complex diseases. The recent development of next-generation sequencing (NGS) platforms provides unprecedented opportunities for the detection of CNVs at a base-level resolution. However, due to the intrinsic characteristics behind NGS data, accurate detection of CNVs is still a challenging task. In this article, we propose a new density peak-based method, called dpCNV, for the detection of CNVs from NGS data. The algorithm of dpCNV is designed based on density peak clustering algorithm. It extracts two features, i.e., local density and minimum distance, from sequencing read depth (RD) profile and generates a two-dimensional data. Based on the generated data, a two-dimensional null distribution is constructed to test the significance of each genome bin and then the significant genome bins are declared as CNVs. We test the performance of the dpCNV method on a number of simulated datasets and make comparison with several existing methods. The experimental results demonstrate that our proposed method outperforms others in terms of sensitivity and F1-score. We further apply it to a set of real sequencing samples and the results demonstrate the validity of dpCNV. Therefore, we expect that dpCNV can be used as a supplementary to existing methods and may become a routine tool in the field of genome mutation analysis.

GOLPH3 Promotes Cancer Growth by Interacting With STIP1 and Regulating Telomerase Activity in Pancreatic Ductal Adenocarcinoma

Overexpression of Golgi phosphoprotein 3 (GOLPH3) predicts poor prognosis and is a potential therapeutic target in pancreatic ductal adenocarcinoma (PDAC). However, its role and underlying molecular mechanisms in the progression of PDAC remain unknown. In the present study, using high-throughput bimolecular fluorescence complementation (BiFC) analysis, we identified that stress-inducible protein-1 (STIP1) interacts with GOLPH3 and confirmed the interaction using co-localization and co-immunoprecipitation. The levels of GOLPH3 and STIP1 in PDAC tissues and adjacent non-cancerous pancreatic tissues were determined using immunohistochemistry (IHC) and quantitative real-time reverse transcription PCR. Real-time Quantitative-telomere repeat amplification (Q-TRAP) was applied to detect relative telomerase activity, and cell proliferation was measured when small interfering RNAs targeting GOLPH3 or STIP1 were transfected into PDAC cell lines. BALB/c nude mice were used to assess tumor growth inhibition of BXPC3 cells stably transfected with GOLPH3 short hairpin RNA. In summary, GOLPH3 was found to interact with STIP1 and both proteins were overexpressed and co-localized in PDAC tissues and cell lines. Moreover, suppression of GOLPH3 expression using shRNAs in PANC1 and BXPC3 cells inhibited tumor cell proliferation both in vitro and in vivo. Mechanistically, GOLPH3 interacts with STIP1 to activate telomerase reverse transcriptase (hTERT) and telomerase activity by c-Myc, and then upregulates cell cycle-related signaling proteins, including cyclin D1, to promote tumor cell growth, suggesting that disrupting the interaction between STIP1 and GOLPH3 would be a promising new strategy to treat PDAC.

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.

Golgi reassembly and stacking protein 65 downregulation is required for the anti-cancer effect of dihydromyricetin on human ovarian cancer cells

Golgi reassembly and stacking protein 65 (GRASP65), which has been involved in cancer progression, is associated with tumor growth and cell apoptosis. Dihydromyricetin (DHM) has demonstrated antitumor activity in different types of human cancers. However, the pharmacological effects of DHM on ovarian cancer (OC) and the molecular mechanisms that underlie these effects are largely unknown. The present study showed that DHM reduced cell migration and invasion in a concentration- and time-dependent manner and induced cell apoptosis primarily through upregulation of Cleaved-caspase-3 and the Bax/Bcl-2 ratio in OCs. To further clarify the cancer therapeutic target, we assessed the effect of DHM on the expression of GRASP65, which is overexpressed in human ovarian cancer tissues. DHM activated caspase-3 and decreased GRASP65 expression to promote cell apoptosis, implying that downregulation of GRASP65 was related to DHM-induced cell apoptosis. Additionally, the knockdown of GRASP65 by siRNA resulted in increased apoptosis after DHM treatment, while western blot and flow cytometry analysis demonstrated that overexpression of GRASP65 attenuated DHM-mediated apoptosis. In addition, the JNK/ERK pathway may be involved in DHM-mediated caspase-3 activation and GRASP65 downregulation. Taken together, these findings provide novel evidence of the anti-cancer properties of DHM in OCs, indicating that DHM is a potential therapeutic agent for ovarian cancer through the inhibition of GRASP65 expression and the regulation of JNK/ERK pathway.

Mouse mammary tumor viral env sequences are not present in the human genome but are present in breast tumors and normal breast tissues

In 1936, John Joseph Bittner identified mouse mammary tumor virus (MMTV), a milk transmitted beta retrovirus, a form of single-stranded positive-sense RNA virus. A retrovirus inserts a copy of its genome into the DNA of a host cell, thus altering the cell's genome. In the current analysis, we searched for MMTV sequences within the human genome. To compare the MMTV genome to the human genome, we used BLAT, the Blast-Like Alignment Tool of the UCSC Genome Browser. BLAT can align a user sequence of 25 bases or more to the genome. 60 MMTV sequences were in the human genome. Of 56 sequences from the MMTV POL gene, 36 POL sequences were from the same part of the gene, beginning at viral nucleotide 4800 but of different lengths. 8 viral sequences began at nucleotide ∼3430 of the POL gene. Four viral sequences were from GAGdUTPase, encoded by the MMTV PRO gene. Deoxyuridine 5'-triphosphate nucleotidohydrolase (dUTPase) is an enzyme present in several major retroviral families. In MMTV dUTPase may be essential for viral replication. Since BLAT identified no MMTV envelope (env) sequence in the human genome, the env sequences from breast tumors and normal breast tissue found in other studies may have come from an MMTV infection. However, no one is certain how MMTV could enter human cells, since the cells do not have a cellular receptor for MMTV, as do mouse cells.

Establishment of a SVM classifier to predict recurrence of ovarian cancer

Gene expression data using retrieved ovarian cancer (OC) samples were used to identify genes of interest and a support vector machine (SVM) classifier was subsequently established to predict the recurrence of OC. Three datasets (GSE17260, GSE44104 and GSE51088) investigating OC gene expression were downloaded from the Gene Expression Omnibus. Differentially expressed genes (DEGs) in samples from patients with non-recurrent and recurrent OC were revealed via a homogeneity test and quality control analysis. A protein-protein interaction (PPI) network was subsequently established for the DEGs using data from Biological General Repository for Interaction Datasets, Human Protein Reference Database and Database of Interacting Proteins. Degrees of interaction and betweenness centrality (BC) scores were calculated for each node in the PPI network. The top 100 genes ranked by BC scores were selected to identify feature genes via recursive feature elimination using the GSE17260 dataset. Following this, a SVM classifier was constructed and further validated using the GSE44104 and GSE51088 datasets and independent gene expression data obtained from the Cancer Genome Atlas (TCGA). A total of 639 DEGs were identified from the three gene expression datasets, and a PPI network including 249 nodes and 354 edges was constructed. A SVM classifier consisting of 39 feature genes (including cullin 3, mouse double minute 2 homolog, aurora kinase A, WW domain containing oxidoreducatase, large tumor suppressor kinase 2, sirtuin 6, staphylococcal nuclease and tudor domain containing 1, leucine rich repeats and immunoglobulin like domains 1 and aurora kinase 1 interacting protein 1) was subsequently constructed. The prediction accuracies of the SVM classifier for GSE17260, GSE44104 and GSE51088 datasets as well as data downloaded from TCGA were revealed to be 92.7, 93.3, 96.6 and 90.4%, respectively. Furthermore, the results of the present study revealed that patients with predicted non-recurrent OC survived significantly longer compared with the patients with predicted recurrent OC (P=6.598×10⁻⁶). A SVM classifier consisting of 39 feature genes was established for predicting the recurrence and prognosis of OC. Therefore, the results of the present study suggested that the 39 feature genes may serve important roles in the development of OC and may represent therapeutic biomarkers of OC.

Expression of GOLPH3 in patients with non-small cell lung cancer and xenografts models

Increased expression of Golgi phosphoprotein 3 (GOLPH3) has been reported to be associated with several types of human cancer. Patient-derived cancer xenograft models have demonstrated great potential in preclinical studies. In the present study, the link between GOLPH3 expression and survival was examined in patients with non-small cell lung cancer (NSCLC). Patient-derived lung cancer xenograft models were established with two different methods. Lastly, the association between GOLPH3 expression and establishment of the xenograft models was explored. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry analysis were used to examine GOLPH3 expression in 60 NSCLC tissues and matched adjacent non-cancerous tissues (ANT). In addition, tumor pieces from the 60 NSCLC tissues were implanted in the subcutaneous layer and in the subrenal kidney capsule of nude mice. RT-qPCR, histopathology and immunohistochemistry were used to confirm the human origin of the xenograft tumors. RT-qPCR was also used to research the mutation status of GOLPH3 in the xenograft tumors. The results demonstrated that NSCLC tissues had higher expression of GOLPH3, at the mRNA and protein level, compared with ANT. High expression of GOLPH3 correlated with poor survival in patients with NSCLC. Successful engraftment was established for 27 tissues in the subrenal kidney capsule and for 16 in the subcutaneous layer of nude mice. The subrenal kidney capsule group demonstrated significantly higher engraftment rates than the subcutaneous layer group. In addition, higher GOLPH3 expression in the tumor tissues was significantly correlated with higher engraftment rates in mice. In both groups, few xenografts lost the GOLPH3 mutation. In summary, GOLPH3 may be an important diagnosis and prognosis indicator in patients with NSCLC. The genotype and phenotype of the xenograft tumors derived from patient lung cancer tissues exhibited significant similarities to the originating primary tumors. High GOLPH3 expression may promote the successful establishment of xenograft models for NSCLC.

GOLPH3: a novel biomarker that correlates with poor survival and resistance to chemotherapy in breast cancer

The association between Golgi phosphoprotein 3 (GOLPH3) and clinical pathological characteristics, as well as the clinical outcomes of both neoadjuvant and adjuvant chemotherapies in breast cancer, remain largely unknown. In this study, we investigated the biological role and clinical significance of GOLPH3 in breast cancer. We found that GOLPH3 expression in tumor tissue was higher than that in adjacent noncancerous tissue (ANT) and fibroadenoma. GOLPH3 silencing reduced the migration, invasion, and proliferation of breast cancer cells and promoted apoptosis of the cells. Importantly, patients with high GOLPH3 expression had worse disease-free survival (DFS) and overall survival (OS), and GOLPH3 expression was correlated with clinical pathological characteristics such as molecular subtype, tumor-node-metastasis classification, and age but was not associated with surgery type. Patients with high GOLPH3 expression had poor DFS and OS in every molecular subtype, and an increase in tumor invasion and lymph node metastasis. The risk of recurrence increased with age in patients with high GOLPH3 expression, and surgery type had no influence on patient survival. This is the first study to investigate the correlation between GOLPH3 and response to chemotherapy in breast cancer. Patients with high GOLPH3 expression showed resistance to neoadjuvant and adjuvant chemotherapies, and GOLPH3 overexpression indicated a high risk of recurrence in patients who received adjuvant chemotherapy. These data suggest that GOLPH3 may be a novel biomarker that correlates with poor survival and resistance to chemotherapy in breast cancer.

The oncogenic Golgi phosphoprotein 3 like overexpression is associated with cisplatin resistance in ovarian carcinoma and activating the NF-κB signaling pathway

Background

Chemo-resistance is a leading cause of tumor relapse and treatment failure in patients with ovarian cancer. The identification of effective strategies to overcome drug resistance will have a significant clinical impact on the disease.

Methods

The protein and mRNA expression of GOLPH3L in ovarian cancer cell lines and patient tissues were determined using Real-time PCR and Western blot, respectively. 177 human ovarian cancer tissue samples were analyzed by IHC to investigate the association between GOLPH3L expression and the clinicopathological characteristics of ovarian cancer patients. Functional assays, such as MTT, FACS, and Tunel assay used to determine the oncogenic role of GOLPH3L in human ovarian cancer progression. Furthermore, western blotting and luciferase assay were used to determine the mechanism of GOLPH3L promotes chemoresistance in ovarian cancer cells.

Results

The expression of GOLPH3L was markedly upregulated in ovarian cancer cell lines and tissues, and high GOLPH3L expression was associated with an aggressive phenotype and poor prognosis with ovarian cancer patients. GOLPH3L overexpression confers CDDP resistance on ovarian cancer cells; however, inhibition of GOLPH3L sensitized ovarian cancer cell lines to CDDP cytotoxicity both in vitro and in vivo. Additionally, GOLPH3L upregulated the levels of nuclear p65 and phosphorylated inhibitor of nuclear factor Kappa-B kinase-β and IκBα, thereby activating canonical nuclear factor-κB (NF-κB) signaling.

Conclusions

Our findings suggest that GOLPH3L is a potential therapeutic target for the treatment of ovarian cancer: targeting GOLPH3L signaling may represent a promising strategy to enhance platinum response in patients with chemoresistant ovarian cancer.

Electronic supplementary material

The online version of this article (10.1186/s13046-017-0607-0) contains supplementary material, which is available to authorized users.

GOLPH3 induces epithelial-mesenchymal transition via Wnt/β-catenin signaling pathway in epithelial ovarian cancer

Golgi phosphoprotein 3 (GOLPH3), a newly recognized oncogene, is associated with tumor growth, metastasis, and poor prognosis in several types of cancer. However, its biological role and underlying mechanism in epithelial ovarian cancer (EOC) remain poorly understood. Here, we found that GOLPH3 was overexpressed in EOC tissues and cell lines. This overexpression promoted the migration and invasion of EOC cells. Moreover, GOLPH3 upregulated the expression of epithelial–mesenchymal transition (EMT) markers, such as N‐cadherin and Snail, and the Wnt/β‐catenin‐related genes cyclin‐D1 and c‐Myc, which were restored via silencing of GOLPH3 expression. Furthermore, the inhibitor and activator of the Wnt/β‐catenin pathway, XAV939 and LiCl, enhanced or decreased, respectively, the effect of GOLPH3 on EMT, which further confirmed that GOLPH3 promoted EMT progression via activation of Wnt/β‐catenin signaling. In addition, we found that EDD, the human hyperplastic discs gene, was consistent with GOLPH3 expression and also promoted the EMT process and activated Wnt/β‐catenin signaling. These findings demonstrate that EDD might be a downstream factor of GOLPH3. Taken together, our findings demonstrate the existence of a GOLPH3–Wnt/β‐catenin–EMT axis in EOC and provide a new therapeutic target to treat EOC.

The Role of GOLPH3L in the Prognosis and NACT response in Cervical Cancer

Background: We previously reported GOLPH3L is a novel oncogene associated with ovarian cancer. The role of GOLPH3L in cervical cancer and its cellular functions has not been determined. This study investigated clinical significance of GOLPH3L and potential proteins and pathways associated with GOLPH3L in cervical squamous cell carcinoma.

Methods: Immunohistochemistry and western blot were used to examine the expression of GOLPH3L in cervical squamous cell carcinoma tissue specimens and adjacent non-cancerous tissues. The clinical and prognostic significance of GOLPH3L expression was statistically analyzed. Cell proliferation rate, cell cycle progression, apoptosis and cisplatin response in GOLPH3L silenced SiHa and HeLa cells were also examined. Phospho-antibody array was used to identify changes in protein phosphorylation and the corresponding signaling pathways associated with these changes.

Results: GOLPH3L overexpressed in cervical cancer tissue specimens compared with normal adjacent non-cancerous tissues. Increased GOLPH3L expression was associated with FIGO staging (P=0.033), cervical stromal invasion (P=0.037), cervical canal stromal invasion (P=0.027), lymph node metastasis (P=0.016) and positive surgical margins (P=0.015). Patients with lower expression of GOLPH3L demonstrated longer progression-free survival and overall survival compared with those with higher expression. The tissue samples from patients who poorly responded to neoadjuvant chemotherapy (NACT) exhibited increased GOLPH3L expression levels compared with tissue samples from patients who achieved a pathologic complete response (pCR). Patients with lower GOLPH3L expression level, poorer tumor differentiation, shorter NACT treatment intervals and smaller tumor sizes were more likely to achieve a pCR after NACT. Knockdown GOLPH3L in cells was associated with an induction of cell cycle arrest, increased apoptosis and cisplatin sensitivity, and a reduction in cellular viability. Phospho-antibody array suggested GOLPH3L plays a role in mediating cell cycle arrest.

Conclusions: This study provides a potential biomarker for predicting prognosis and NACT response in patients with cervical squamous cell carcinoma. The functional role of GOLPH3L in cervical cancer merits further investigation.

Increased APOBEC3B Predicts Worse Outcomes in Lung Cancer: A Comprehensive Retrospective Study

Lung cancer ranks as the most common and lethal malignancy in America and worldwide. APOBEC3B is a newly identified DNA cytosine deaminase, which is supposed to function as a major source of DNA mutation in many different tumors. In this study, we combine the data of online databases and two hundred and twenty-one primary non-small-cell lung carcinoma (NSCLC) specimens from Sun Yat-sen University Cancer Center to investigate, for the first time, the clinical role of APOBEC3B in lung cancer. We found that the APOBEC3 expression was commonly elevated in NSCLC tissues and overexpression of APOBEC3B was correlated with unfavorable prognosis of the patients with NSCLC. Furthermore, APOBEC3B expression was associated with nodal status, TNM staging and adjuvant chemotherapy of the patients with NSCLC. Further research is warranted.