PC Cell-derived Growth Factor Research Articles

Application Value of Serum TK1 and PCDGF, CYFRA21-1, NSE, and CEA plus Enhanced CT Scan in the Diagnosis of Nonsmall Cell Lung Cancer and Chemotherapy Monitoring

Objective To assess the application value of serum thymidine kinase 1 (TK1) and PC cell-derived growth factor (PCDGF), cytokeratin 19 fragment 21-1 (CYFRA21-1), neuron-specific enolase (NSE), and carcinoembryonic antigen (CEA) plus enhanced CT scan in the diagnosis of nonsmall cell lung cancer (NSCLC) and chemotherapy monitoring. Methods Between April 2019 and April 2021, 30 patients with NSCLC assessed for eligibility treated in our institution were included in the experimental group, and 30 healthy individuals screened out from physical examinations were recruited in the control group. The chemotherapy regimens included gemcitabine plus cisplatin, pemetrexed disodium plus cisplatin, and vinorelbine plus cisplatin. The application value of serum TK1, PCDGF, CYFRA21-1, NSE, CEA, and enhanced CT scan in the diagnosis and chemotherapy monitoring of NSCLC was analyzed. Results Before treatment, the eligible patients had significantly higher serum levels of TK1, PCDGF, CYFRA21-1, NSE, and CEA than those of the healthy individuals included (P < 0.05). Clinical efficacy was categorized into good and poor, and the good efficacy included complete response and partial response, with the poor efficacy including stable disease and progressive disease. Patients with good clinical efficacy had lower levels of serum TK1, PCDGF, CYFRA21-1, NSE, and CEA than those with poor efficacy (P < 0.05). Joint detection showed a larger area under the curve (AUC) (0.900; 95%CI, 0.812-0.988), a higher sensitivity, and a superior detection outcome to the stand-alone detection (P < 0.05). Diagnostic results were similar between joint detection and pathological examination (P > 0.05). Conclusion The application of serum TK1, PCDGF, CYFRA21-1, NSE, and CEA assay plus enhanced CT scan shows high sensitivity and diagnostic accuracy in the diagnosis and chemotherapy monitoring of nonsmall cell lung cancer and thus provides a diagnostic reference basis.

Abstract OT1-05-01: Glycoprotein 88 (GP-88) serum levels as a marker of response to therapy in patients with metastatic breast cancer

Abstract The ability to detect metastatic breast cancer (MBC) &amp; readily monitor response to therapy is an important goal in the management of breast cancer (BC). Imaging is used for the assessment &amp; monitoring of disease progression. However, this is expensive &amp; represents a late marker of disease status. The disease may progress significantly on ineffective treatment &amp; the patient may have treatment related toxicities due to the lack of knowledge of the progression at earlier times. Circulating tumor associated biomarkers CA15-3 &amp; CEA can be used to track disease status of MBC, however, they are not always a reliable measure of disease progression. The monitoring of disease progression through measurement of drivers of disease may better reflect the disease status &amp; enable proactive management sooner. GP88 (granulin/epithelin precursor or progranulin) has been identified as a driver of tumorigenesis &amp; disease progression through its signaling as an autocrine growth &amp; survival factor for several cancers including BC1. We hypothesized that measurement of circulating serum GP88 levels can serve as a biomarker to monitor MBC disease status &amp; be prognostic to outcome 2. Clinical studies have demonstrated circulating levels of GP88 statistically differ in healthy volunteers, early BC patients (pts), &amp; pts with metastatic disease &amp; levels correlate with overall survival2,3. The primary aim of this prospective study is to identify whether there is a statistically significant change in serum GP88 levels associated with response to treatment &amp; time to progression of BC as measured by RECIST 1.1 criteria in MBC pts. Under an IRB approved protocol at the University of Maryland Greenbaum Comprehensive Cancer Center, a total of 103 female pts with measurable or evaluable metastatic disease who have been re-staged in within 4 weeks &amp; will continue or begin new therapy &amp; meet the additional criteria will be consented &amp; enrolled. Currently, we have enrolled 23 pts. In addition to standard of care laboratory assessment &amp; radiographic imaging/staging every 2-3 months, blood samples will be collected from each patient. The samples will be stored at -70C until tested for GP88 using a GP88 enzyme linked immunoassay. We will analyze the serial GP88 serum levels &amp; correlate with treatment response using RECIST 1.1 criteria (stable, progression, response), time to progression &amp; overall survival. We assume that pts will provide a baseline &amp; 4 follow up visits/GP-88 levels &amp; that 20% of the visits will record a disease progression &amp; time to progression. The probable &amp; clinically relevant GP-88 test performance will then have 75% sensitivity &amp; 46% false positivity with 85% power in a sample of 90 pts.

GP88 (Progranulin) Confers Fulvestrant (Faslodex, ICI 182,780) Resistance to Human Breast Cancer Cells

The 88 kDa glycoprotein known as GP88, Progranulin or PC cell derived growth factor is an autocrine growth factor with a unique cysteine rich motif that is over expressed in breast cancer whereas it is negative in normal mammary epithelial cells. It has been shown to play a major role in estrogen independence, tamoxifen resistance and tumorigenesis of breast cancer cells. In the present study, we investigated the effect of GP88 overexpression on the response of the human breast cancer MCF-7 cells to the pure estrogen receptor antagonist fulvestrant (ICI 182,780). While fulvestrant effectively inhibited cell proliferation of empty vector transfected cells, it had no inhibitory effect on the proliferation of GP88 overexpressing breast cancer cells. Mouse xenograft experiments in athymic ovariectomized nude mice showed that GP88 over expressing cells were fulvestrant resistant in vivo in contrast to low GP88 expressing cells. We show that the ability of fulvestrant to induce apoptosis determined by measuring cleavage of poly (ADP-ribose) polymerase was inhibited by GP88. Anti-apoptotic activity of GP88 was associated with sustained expression of bcl-2 and bcl-xL after fulvestrant treatment. In contrast, fulvestrant was still able to inhibit the ability of estrogen to stimulate ERE-luciferase reporter gene activity as well as vEGF expression in GP88 over expressing MCF-7 cells similarly to control MCF-7 cells. Collectively, our data suggest that GP88 prevents apoptosis induced by faslodex and contributes to antiestrogen resistance in human breast cancer.

Abstract OT3-2-11: A phase II study of letrozole and lapatinib followed by an addition of everolimus in postmenopausal women with advanced endocrine resistant breast cancer (BC)

Abstract Background: Several preclinical studies demonstrated that crosstalk between growth factor receptor pathways, particularly HER2, and ER signaling confers resistance to endocrine therapy (ET). There are emerging data showing the involvement of immune system and miRNA with endocrine resistance. EGF30008 trial showed a benefit of lapatinib in combination with letrozole, mainly in HER2-positive (HER+) metastatic BC (MBC) while a subset analysis of this trial showed that HER2-negative (HER2-) patients (pts) with acquired endocrine resistance may also benefit from this combination. Our preclinical study suggests that everolimus is synergistic with letrozole and lapatinib. Trial Design: This is a single arm phase II study for postmenopausal women with hormone receptor-positive MBC progressing after aromatase inhibitor, tamoxifen, or fulvestrant. The total target accrual is 76 pts (38 HER2+ pts and 38 HER- pts). In the first phase of the study, pts will be treated with letrozole and lapatinib (1,500 mg daily). Upon disease progression, pts will enter the second phase where everolimus (5 mg daily) will be added to letrozole and the dose of lapatinib will be reduced to 1,250 mg daily. For correlative studies, peripheral blood samples will be serially collected to evaluate for serum HER2 extracellular domain (ECD), circulating miRNAs, PC cell-derived growth factor (GP88), immune regulatory cells including myeloid-derived suppressor cells, NK cells, and Treg cells. These parameters will be correlated with tumor response. In pts with accessible tumors, optional serial biopsies will be performed at baseline and upon progression in each phase of the study. The tumor tissue will be tested for total HER1, HER2, and HER2 expressions as well as HER2:HER2 homodimers, HER2:HER3 heterodimers, HER1:HER2 heterodimers, p95, and HER3/PI3K (p85 subunit) using VeraTag assay. Statistical Method: The primary objective is to evaluate the clinical benefit rate (CBR: CR, PR, SD &amp;gt; 24 weeks) of the combination of letrozole and lapatinib as well as the combination of everolimus, letrozole, and lapatinib. This is a three-stage design which is an extension of the Simon's two-stage design. The sample size is based on the assumption that a CBR below 10% (null hypothesis) would indicate ineffective therapy and the statistical power is set at a higher CBR of 30% which we consider is plausible. Therefore, if 0 of the first 10 pts in each cohort have clinical benefit, the study will be closed; otherwise additional 8 pts will be enrolled. If ≤ 1 of the total 18 pts has clinical benefit, the study will be closed; otherwise an additional 9 pts will be enrolled. If ≤ 5 pts have clinical benefit the therapy is considered not promising; and if ≥ 6 pts of the total of 27 have clinical benefit, the therapy is considered worth pursuing. This design has ∼90% probability to accept the therapy for further trials if the true CBR is indeed at least 30% and 10% probability to accept it if the true clinical benefit is indeed below 10%. To date, there are a total of 6 pts enrolled. Accrual is currently ongoing. Please contact ntait@umm.edu for further information. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr OT3-2-11.

Effect of PC cell-derived growth factor RNA interference on biological behavior of esophageal squamous carcinoma cells

To investigate the effect of PC cell-derived growth factor (PCDGF) RNA interference on esophageal squamous carcinoma cells Eca-109 in vitro. The PCDGF-shRNA expression vector was transfected into the Eca-109 cells by liposome. After transfection, the mRNA and protein expressions of PCDGF were detected by RT-PCR and Western-blot respectively. Cell Counting Kit-8 (CCK-8) assay and Boyden chamber method were performed to measure the cell proliferation and invasion ability respectively. The expression levels of PCDGF mRNA and protein were both decreased in Eca-109 cells transfected with PCDGF-shRNA expression vector (transfection group). Twenty-four, 48 and 72 h after transfection, the cells proliferation in the transfection group was inhibited, and the inhibition rate was 20.4%, 21.1% and 20.9% respectively. The cell proliferation activity in the transfection group was significantly lower than that in the non-transfection group, liposome group and negative vector group (all P<0.05). The number of cell migration in the non-transfection group,negative vector group, liposome group and transfection group was 118.8±12.0, 100.8±9.0, 114.3±4.7, and 53.5±16.3 respectively. The differences were statistically significant between the transfection group and the other 3 groups (all P<0.05). PCDGF RNA interference can inhibit the proliferation and invasion abilities of esophageal squamous carcinoma cells in vitro. PCDGF gene may be the new target of gene therapy.

Abstract B91: A novel role for the secreted growth factor progranulin in angiogenesis

Abstract Progranulin (also called PC cell-derived growth factor, acrogranin or proepithelin), is a secreted glycoprotein with growth factor-like activities. It is often highly over-expressed in tumors including cancers of the breast, ovary, endometrium, kidney, prostate, bladder and liver. It stimulates cellular proliferation, migration and survival and increases the growth of cancers in mice. Recent work suggests that progranulin has, in addition, potentially important roles in fibroblast activation during the formation of tumor stroma. An elevated progranulin level has been observed in endothelial cells in some cancers including ovarian tumors, esophageal carcinomas and gliomas. Since progranulin is not expressed in normal quiescent endothelia, its presence in endothelial cells from cancers prompted us to propose that progranulin may have a novel role in tumor angiogenesis. It is, however, unknown at present, how, if at all, progranulin modulates angiogenesis in vivo. To address this question we created transgenic models in which progranulin expression is specifically targeted to endothelial cells under the control of the Tie2 promoter. Three independent transgenic lines were obtained, with lower (Tie2-GrnLo), intermediate (Tie2-GrnMid) and higher (Tie2-GrnHi) transgene copy number. Increased mortality was observed in heterozygotic crosses from all three transgenic lines, with the highest mortality and lowest germline transmission ratio in the Tie2-GrnHi line; at three weeks after birth the germline transmission ratios of Tie2-Grn positive mice were 26.01%, 19.61% and 4.72% for PgrnLo, PgrnMid and PgrnHi respectively. Premature deaths occurred during the perinatal period after embryonic day 17.5 and before post-natal day 3. Importantly, we observed an array of vascular abnormalities in Tie2-Grn transgenic neonates. These include extensive bleeding into body cavities such as the pericardial space as well as smaller localized hemorrhages in multiple organs. The abnormal blood vessels had dramatically enlarged diameters with irregular edges; several had an incomplete basement membranes and, typically, the perivascular cell coverage was reduced or absent when compared to Tie2-Grn negative litter mates. To establish the developmental timing of vascular disruption, we examined Tie2-GrnHi mice from embryonic day 10.5 to fetal age 17.5. An apparently normal primitive vasculature was established at E10.5 in Tie2-Grn positive embryos suggesting that vasculogenesis proceeded normally. The earliest onset of vascular impairment was observed at E15.5, after vasculogenesis has occurred but during active angiogenesis. As with neonates, from E15.5 and later, vessels became enlarged and perivascular cell investiture was reduced contributing to loss of structural integrity and causing the blood vessels to be prone to hemorrhaging. Given the vessel dilation in Tie2-Grn positive late-stage fetuses and neonates we conclude that progranulin is a novel regulator of angiogenesis. The elevated expression of progranulin by endothelial cells is observed in some cancers in vivo, and, as we report here, in transgenic mice results in the development of enlarged, disorganized, thin-walled vessels that resemble to some extent the disorganized blood vessels in tumors. We suggest, therefore, that progranulin may be significant in regulating tumor angiogenesis. Citation Format: Huishi Toh, Ming Cao, Yonghua Zhang, Eugene Daniels, Andrew Bateman. A novel role for the secreted growth factor progranulin in angiogenesis. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Invasion and Metastasis; Jan 20-23, 2013; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2013;73(3 Suppl):Abstract nr B91.

Significance of PC cell-derived growth factor and cyclin D1 expression in cutaneous squamous cell carcinoma

PC cell-derived growth factor (PCDGF) is an autocrine growth factor originally purified from the highly tumorigenic teratoma PC cell line. It participates in tumorigenesis and tumour progression through upregulation of cyclin D1. To date, there has been no report on the role of PCDGF in skin cancer, to our knowledge. To investigate the expression of PCDGF and cyclin D1 in basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and seborrhoeic keratosis (SK), and their relationship with the clinicopathological parameters of SCC. Immunohistochemical expression of PCDGF and cyclin D1 was examined in 42 SCC, 30 BCC and 20 SK tissues. PCDGF and cyclin D1 were overexpressed in SCC or BCC tissues compared with normal skin or SK, and their expressions were significantly higher in SCC than in BCC. Moreover, positive expression of PCDGF and cyclin D1 was significantly correlated with depth of invasion and metastasis of SCC. There was significant correlation between PCDGF and cyclin D1 expression in SCC. Expression of PCDGF and cyclin D1 plays an important role in the tumorigenesis of BCC and SCC. Abnormal expression of PCDGF and Cyclin D1 may be related to invasion and metastasis of SCC.

GP88 (PC-Cell Derived Growth Factor, progranulin) stimulates proliferation and confers letrozole resistance to aromatase overexpressing breast cancer cells

BackgroundAromatase inhibitors (AI) that inhibit breast cancer cell growth by blocking estrogen synthesis have become the treatment of choice for post-menopausal women with estrogen receptor positive (ER+) breast cancer. However, some patients display de novo or acquired resistance to AI. Interactions between estrogen and growth factor signaling pathways have been identified in estrogen-responsive cells as one possible reason for acquisition of resistance. Our laboratory has characterized an autocrine growth factor overexpressed in invasive ductal carcinoma named PC-Cell Derived Growth Factor (GP88), also known as progranulin. In the present study, we investigated the role GP88 on the acquisition of resistance to letrozole in ER+ breast cancer cellsMethodsWe used two aromatase overexpressing human breast cancer cell lines MCF-7-CA cells and AC1 cells and their letrozole resistant counterparts as study models. Effect of stimulating or inhibiting GP88 expression on proliferation, anchorage-independent growth, survival and letrozole responsiveness was examined.ResultsGP88 induced cell proliferation and conferred letrozole resistance in a time- and dose-dependent fashion. Conversely, naturally letrozole resistant breast cancer cells displayed a 10-fold increase in GP88 expression when compared to letrozole sensitive cells. GP88 overexpression, or exogenous addition blocked the inhibitory effect of letrozole on proliferation, and stimulated survival and soft agar colony formation. In letrozole resistant cells, silencing GP88 by siRNA inhibited cell proliferation and restored their sensitivity to letrozole.ConclusionOur findings provide information on the role of an alternate growth and survival factor on the acquisition of aromatase inhibitor resistance in ER+ breast cancer.

Increased Circulating Level of the Survival Factor GP88 (Progranulin) in the Serum of Breast Cancer Patients When Compared to Healthy Subjects

Introduction:GP88 (PC-Cell Derived Growth Factor, progranulin) is a glycoprotein overexpressed in breast tumors and involved in their proliferation and survival. Since GP88 is secreted, an exploratory study was established to compare serum GP88 level between breast cancer patients (BC) and healthy volunteers (HV).Methods:An IRB approved prospective study enrolled 189 stage 1–4 BC patients and 18 HV. GP88 serum concentration was determined by immunoassay.Results:Serum GP88 level was 28.7 + 5.8 ng/ml in HV and increased to 40.7 + 16.0 ng/ml (P = 0.007) for stage 1–3 and 45.3 + 23.3 ng/ml (P = 0.0007) for stage 4 BC patients. There was no correlation between the GP88 level and BC characteristics such as age, race, tumor grade, ER, PR and HER-2 expression.Conclusion:These data suggest that serial testing of serum GP88 levels may have value as a circulating biomarker for detection, monitoring and follow up of BC.

Increased circulating level of the autocrine growth factor GP88 (PC cell-derived growth factor factor/progranulin) in early- and advanced-stage non-small cell lung cancer and small cell lung cancer.

e18103 Background: GP88, is an 88 kDa glycoprotein autocrine growth factor belonging to a newly identified family of growth modulators characterized by unique cysteine-rich motif and playing a role in the proliferation and survival of human cancers by inhibiting apoptosis, stimulating cell migration and invasiveness, and promoting metastasis. In vitro and in vivo studies have examined the biological activity and expression of GP88 in human breast cancer. In particular, pathological and clinical studies investigating the expression of GP88 in lesions and sera from breast cancer patients demonstrated GP88 expression was associated with clinically poor prognosis. The current study evaluated GP88 in lung cancer. Methods: 28 patients newly diagnosed with SCLC or NSCLC or previously diagnosed lung cancer and undergoing chemotherapeutic regimen change were enrolled. 20 healthy adults with similar background, including history of smoking, were enrolled as control group. Venous blood was collected and serum GP88 was tested by human GP88 ELISA. Results: 28 patients enrolled. 6 SCLC (1 Limited stage SCLC, five extended stage SCLC). 22 NSCLC, stage IV: 16, stage III: 3 and stage I: 3. The mean serum GP88 level in the lung cancer study group was 46.5 ± 15.5 ng/mL while the mean serum GP88 level in the control group was 28.4 ± 5.6 ng/mL, p = 0.0004 (Wilcoxon rank sum test). Conclusions: In patients diagnosed with SCLC/NSCLC, there is a statistically significant increase of serum GP88. Further studies will be planned to explore the role of GP88 as a biomarker for diagnosis and prognosis of lung cancer. We are currently accruing additional pts and analyzing whether GP88 has prognostic or predictive value. No significant financial relationships to disclose.

The Growth Factor GP88 (Progranulin) Confers Aromatase Inhibitor Resistance to Breast Cancer Cells.

Abstract The development of aromatase inhibitors has provided novel therapeutic strategies for post-menopausal patients with estrogen receptor positive (ER+) breast tumors. Aromatase inhibitors, such as letrozole, inhibit ER+ breast cancer cell growth by blocking the synthesis of estrogen by the enzyme aromatase in the tumor stroma. However, ER+ breast cancer cases can sometimes fail or cease to benefit from such therapy. Several mechanisms have been proposed for aromatase inhibitor resistance. Here, we investigate the role of the 88 kDa autocrine growth factor PC-Cell Derived Growth Factor, also known as GP88 or progranulin on the acquisition of aromatase inhibitors resistance by ER+ breast cancer cells. GP88 is the largest member of the epithelin-granulin family characterized by a unique cysteine rich motif. GP88 has been shown to play a role in breast tumorigenesis. GP88 expression increased in breast cancer cells in a positive correlation with tumorigenesis whereas inhibition of GP88 expression lead to a 98% reduction in tumor incidence and growth rate in vivo. Pathological studies of paraffin embedded breast cancer biopsies have shown that GP88 is expressed in infiltrating ductal carcinoma (IDC) in correlation with expression of parameters of poor prognosis but was independent from Her-2 expression. Most importantly, increased GP88 expression in ER+ IDC was associated with increased recurrence and decreased overall survival. The present study investigated the effect of GP88 on the proliferation and letrozole responsiveness of ER+ breast cancer cells that express high aromatase activity (MCF-7 CA and MCF-7 AC1 cells). For both cell types, GP88 added exogenously conferred letrozole resistance in a time and dose-dependent fashion. GP88 also stimulated survival and soft agar colony formation of MCF-7-CA and AC1 cells in the presence of letrozole. GP88 overexpressing cells displayed higher basal levels of phosphorylated ERK1/2 and AKT, both known to be activated in GP88 mitogenic signaling pathways. In addition, naturally letrozole resistant breast tumors displayed a 10-fold increase in GP88 expression when compared to letrozole sensitive cells. Treatment of these letrozole resistant cells with GP88 SiRNA lead to a dose dependent inhibition of proliferation and restoration of letrozole sensitivity indicating that GP88 is regulating the ability of the cells to respond to letrozole.These data show the importance of GP88 as a target for the development of diagnostic and therapeutic products for aromatase inhibitor resistant breast cancer. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4171.

Expression of PC-cell-derived growth factor in breast cancer

This study is mainly aimed at evaluating the expression of PC-cell-derived growth factor (PCDGF) in breast cancer and breast adenofibroma, and to compare with other commonly used clinical pathological indices, then to investigate the diagnostic and targeted therapeutic purpose of PCDGF in breast cancer tissue. In this study, we detected the expression of PCDGF, p53 and CerbB-2 in breast cancer tissue and the expression of PCDGF in breast adenofibroma tissue by immunohistochemical method, and analyzed the relationship between them. We found that PCDGF was expressed in most breast cancer tissue, but was not in breast adenofibroma tissue, and the expression of PCDGF was related with the tumor’s pathological category and the expression of estrogen receptor (ER) and progesterone receptor (PR) and p53, but there was no statistical dependability between PCDGF and cerbB-2. From this study, we predict that PCDGF may serve as a marker in the secondary diagnosis of breast cancer, and may participate in the generation and differentiation of breast cancer cells, and become an effective target of therapy for breast cancer.

Proepithelin Regulates Prostate Cancer Cell Biology by Promoting Cell Growth, Migration, and Anchorage-Independent Growth

The growth factor proepithelin has recently emerged as an important regulator of transformation in several physiological and pathological systems. In this study, we determined the biological roles of proepithelin in prostate cancer cells using purified human recombinant proepithelin as well as proepithelin-depletion strategies. Proepithelin promoted the migration of androgen-dependent and -independent human prostate cancer cells; androgen-independent DU145 cells were the more responsive. In these cells, proepithelin additionally stimulated wound closure, invasion, and promotion of cell growth in vitro. These effects required the activation of both the Akt and mitogen-activated protein kinase pathways. We have analyzed proepithelin expression levels in different available prostate cancer microarray studies using the Oncomine database and found a statistically significant increase in proepithelin mRNA expression levels in prostate cancers compared with nonneoplastic controls. Notably, depletion of endogenous proepithelin by siRNA and antisense strategies impaired the ability of DU145 cells to grow and migrate after serum withdrawal and inhibited anchorage-independent growth. Our results provide the first evidence for a role of proepithelin in stimulating the migration, invasion, proliferation, and anchorage-independent growth of prostate cancer cells. This study supports the hypothesis that proepithelin may play a critical role as an autocrine growth factor in the establishment and initial progression of prostate cancer. Furthermore, proepithelin may prove to be a useful clinical marker for the diagnosis of prostate tumors.

Inhibitory effects of an antisense PCDGF vector on proliferation and invasion of highly malignant ovarian cancer cells and the related mechanism

To investigate the inhibitory effects of an antisense PC cell derived growth factor (PCDGF) vector on proliferation and invasion of highly malignant ovarian cancer cell lines Sw626 and A2780 cells, and preliminarily explore the related mechanisms. MTT assay and Boyden chamber in vitro invasion assay were employed to detect the changes of proliferation and invasion ability in the Sw626 and A2780 cells transfected with anti-sense PCDGF. The expression levels of cyclin D1 and CDK4 proteins before and after transfection were detected by Western blotting. The effects on the expression and activity of MMP-2 were evaluated by quantitative RT-PCR and zymography, respectively. Comparing with the blank group, the proliferation inhibition rate of the Sw626 and A2780 cells transfected with anti-sense PCDGF was 72.9% and 70.9%, respectively, and the invasion ability was inhibited by 62.9% and 59.0%, respectively. The levels of cyclin D1 and CDK4 protein expression in antisense PCDGF transfected cells were 0.38 +/- 0.08 and 0.37 +/- 0.13, respectively, all significantly lower than 0.84 +/- 0.11 and 0.64 +/- 0.11, respectively, in the blank group (P < 0.01). The MMP-2 mRNA expression level in antisense PCDGF transfected cell group was 0.66 +/- 0.11, not significantly decreased in comparison with 0.89 +/- 0.09 in the blank group (P > 0.05), but the activity of MMP-2 was inhibited significantly. The antisense PCDGF vector may inhibit markedly the proliferation and invasion of highly malignant ovarian cancer cells, and partially reverses their malignant phenotype. It seems to be related with down-regulating the expression of cyclin D1 and CDK4 and inhibiting the activity of MMP-2. Our findings indicate that PCDGF may become a new target for antisense gene therapy of ovarian cancer.

Expression of PC cell-derived growth factor and vascular endothelial growth factor in esophageal squamous cell carcinoma and their clinicopathologic significance

Esophageal carcinoma is a common kind of malignant tumor and about 90% of which is esophageal squamous cell carcinoma (ESCC), and it has a high incidence in China. In recent years it has been argued that angiogenesis plays a key role in tumor growth and metastasis and it is a complex process influenced by many factors. This study was aimed to investigate the expression of PC cell-derived growth factor (PCDGF or progranulin) and vascular endothelial growth factor (VEGF) in ESCC tissue and their relationship with clinical pathological parameters of ESCC, clarify the role of PCDGF and VEGF in the angiogenesis of ESCC. The expression of PCDGF and VEGF in 50 surgical specimens from patients with ESCC and 20 with normal esophageal mucosa were detected by immunohistochemistry. The vascular endothelial cells in tumor tissues were labeled by antibody to CD105 for counting microvessel density (MVD). The expression of PCDGF and VEGF in ESCC was significantly higher than that in normal mucosa. Expression correlated with the depth of tumor invasion, lymph node metastasis, and TNM (classification tumor, nodes, metastasis). In ESCC, both the expression level of PCDGF and VEGF had a positive correlation with MVD and the expression of PCDGF had a significant correlation with the expression of VEGF. These results show that both of PCDGF and VEGE have higher expression in ESCC, which indicate that they have a close relationship with angiogenesis. They may be involved in tumor growth, infiltration and metastasis through promoting tumor angiogenesis and may be an important index reflecting biological behavior and prognosis of ESCC.

Effect of PC-cell derived growth factor shRNA on estrogen dependent of estrogen receptor negative breast cancer cell lines

To analyze the relationship between estrogen dependence of breast cancer cells and expression level of PC-cell derived growth factor (PCDGF) and investigate the possibility of practicing endocrine therapy in estrogen receptor negative breast cancer. Expression level of PCDGF mRNA was detected by fluorescence quantitative polymerase chain reaction and cell growth curve was drawn by cell count kit-8 method, then analyzed the relationship between the expression of PCDGF and dependence of estrogen. PCDGF shRNA vector was constructed and transfected into breast cancer cell lines (MCF-7 and MDA-MB-231) using Lipofectamin 2000, examined and compared the changes of estrogen dependence between the two cell lines. PCDGF was expressed in most breast cancer cell lines, and the growth dependence of estrogen was higher in the cells with high-expressing PCDGF than those with low-expressing PCDGF. Expression of PCDGF could be inhibited by transfected shRNA into MCF-7 and MDA-MB-231 (inhibition rates were 81.1% and 86.7% respectively), inhibition of the expression of PCDGF could lead to higher growth dependence of estrogen, and the dependence of MDA-MB-231 was increased much more than MCF-7(P < 0.05). The expression level of PCDGF is higher in estrogen receptor negative breast cancer than in estrogen receptor positive breast cancer. Inhibiting the expression of PCDGF could reverse resistance of endocrine therapy especially to estrogen receptor negative breast cancer.

Inhibition of PC cell-derived growth factor (PCDGF)/granulin-epithelin precursor (GEP) decreased cell proliferation and invasion through downregulation of cyclin D and CDK 4 and inactivation of MMP-2

BackgroundPC cell-derived growth factor (PCDGF), also called epithelin/granulin precursor (GEP), is an 88-kDa secreted glycoprotein with the ability to stimulate cell proliferation in an autocrine fashion. In addition, some studies indicated that PCDGF participated in invasion, metastasis and survival of cancer cells by regulating cell migration, adhesion and proliferation. Yet the effects of PCDGF on proliferation and invasion of ovarian cancer cells in vitro and the mechanisms by which PCDGF mediates biological behaviors of ovarian cancer have rarely been reported. In the present study we investigated whether and how PCDGF/GEP mediated cell proliferation and invasion in ovarian cancer.MethodsPCDGF/GEP expression level in three human ovarian cancer cell lines of different invasion potential were detected by RT-PCR and western blot. Effects of inhibition of PCDGF expression on cell proliferation and invasion capability were determined by MTT assay and Boyden chamber assay. Expression levels of cyclin D1 and CDK4 and MMP-2 activity were evaluated in a pilot study.ResultsPCDGF mRNA and protein were expressed at a high level in SW626 and A2780 and at a low level in SKOV3. PCDGF expression level correlated well with malignant phenotype including proliferation and invasion in ovarian cancer cell lines. In addition, the proliferation rate and invasion index decreased after inhibition of PCDGF expression by antisense PCDGF cDNA transfection in SW626 and A2780. Furthermore expression of CyclinD1 and CDK4 were downregulated and MMP-2 was inactivated after PCDGF inhibition in the pilot study.ConclusionPCDGF played an important role in stimulating proliferation and promoting invasion in ovarian cancer. Inhibition of PCDGF decreased proliferation and invasion capability through downregulation of cyclin D1 and CDK4 and inactivation of MMP-2. PCDGF could serve as a potential therapeutic target in ovarian cancer.

PC cell-derived growth factor overexpression promotes proliferation and survival of laryngeal carcinoma

PC cell-derived growth factor is a novel growth factor for tumor formation and progression. No comprehensive literature concerning PC cell-derived growth factor expression status and its biological function in squamous cell carcinoma, especially in the larynx, is, however, available. The target of this study is to evaluate the clinical significance of PC cell-derived growth factor and the potential of small interfering RNA-induced genetic silencing of PC cell-derived growth factor as a supplementary therapeutic way for laryngeal squamous cell carcinoma. A total of 146 primary laryngeal cancer, 108 adult laryngeal papilloma and 41 laryngeal leukoplakia samples, as well as 10 normal larynx tissues were investigated. The PC cell-derived growth factor mRNA level was examined by real-time polymerase chain reaction and protein localization by immunohistochemistry. The biological function of PC cell-derived growth factor was assessed by transfection of small interfering RNA PC cell-derived growth factor construction. The PC cell-derived growth factor protein levels and mRNA levels of the laryngeal squamous cell carcinomas were significantly higher than those of normal laryngeal tissues (P<0.001). Simultaneously, the difference in the levels of mRNA and protein between those of laryngeal precancerous lesions (papilloma/leukoplakia) and those of normal tissues was significant (P<0.05, P<0.05), whereas those of laryngeal precancerous lesions (papilloma/leukoplakia) were significantly lower than those of laryngeal squamous cell carcinomas (P<0.05, P<0.05). Strong PC cell-derived growth factor expression was associated with lymph node metastases in laryngeal squamous cell carcinoma (P<0.05). Functional studies on Hep-2 cell lines demonstrated that the attenuation of PC cell-derived growth factor expression levels led to diminished cell proliferation rates (P<0.001), anchorage-independent growth in vitro (P<0.001), tumor forming in vivo (P<0.01) and resistance to apoptosis (P<0.001). PC cell-derived growth factor is a pivotal autocrine growth factor in the tumorigenesis of laryngeal squamous cell carcinoma. Our findings also indicate that PC cell-derived growth factor is a logical and potential target for early diagnosis, specific therapy and prognosis of laryngeal squamous cell carcinoma.

PC Cell–Derived Growth Factor Stimulates Proliferation and Confers Trastuzumab Resistance to Her-2-Overexpressing Breast Cancer Cells

Trastuzumab is only effective in 25% to 30% of the administered breast cancer patients who overexpress the erbB2/Her-2 oncoprotein. PC cell-derived growth factor (PCDGF/GP88) is an 88-kDa glycoprotein growth factor overexpressed in 80% invasive ductal carcinomas. Our objective was to determine whether the increased levels of PCDGF/GP88 confers Trastuzumab resistance in erbB2-overexpressing breast cancer cells. The ability of PCDGF to induce erbB2 phosphorylation and to confer Trastuzumab resistance was studied in erbB2-overexpressing MCF-7 and SKBR3 breast cancer cell lines. PCDGF/GP88 added exogenously induced the phosphorylation of erbB2 in a dose-dependent and time-dependent manner in erbB2-overexpressing breast cancer cells. In addition, the overexpression of PCDGF/GP88 conferred Trastuzumab resistance in erbB2-overexpressing cells. Furthermore, overexpression of PCDGF/GP88 in erbB2-overexpressing cells provided a growth advantage over erbB2-overexpressing cells that do not have increased levels of PCDGF/GP88. Lastly, PCDGF/GP88 induced the phosphorylation of mitogen-activated protein kinase in a time-dependent manner in erbB2-overexpressing cells, and pretreatment with Trastuzumab was not able to attenuate the phosphorylation levels of mitogen-activated protein kinase induced by PCDGF/GP88. These data suggest that PCDGF/GP88 confers Trastuzumab resistance in erbB2-overexpressing cells. Thus, the increase in PCDGF/GP88 levels may indicate Trastuzumab unresponsiveness in breast cancer patients.

Circulating levels of the breast cancer growth factor GP88 in the serum of breast cancer (BC) patients

20050 Background: The 88 kDa autocrine growth factor PC-Cell Derived Growth Factor (GP88) plays a critical role in breast tumorigenesis. GP88 expression was low in estrogen receptor positive cells, whereas in ER negative cells, it was constitutively overexpressed. Increased GP88 expression was associated with anti-estrogen therapy resistance in ER+ cells and Herceptin resistance in Her-2 overexpressing breast tumors. Antisense inhibition of GP88 expression in human breast adenocarcinoma lead to inhibition of tumor growth in vivo. Immunohistochemical studies have shown that GP88 was expressed in 80% of invasive ductal carcinomas in correlation with expression of poor prognosis markers whereas normal tissues and benign breast lesions were negative. Since GP88 is secreted by breast cancer cells, we examined whether GP88 was found in the circulation at an elevated level in the sera of breast cancer patients when compared to healthy individuals. Methods: A blood sampling study was conducted to determine the serum level of GP88 in healthy volunteers (HV) and breast cancer patients (BC pts). Ten ml of blood was drawn every three months to obtain serum. GP88 serum concentration was determined in triplicate by quantitative enzyme immunoassay using human GP88 as standard. 126 BC pts were accrued. . In addition, sera from 53 healthy volunteers were obtained to establish a GP88 baseline in HV. BC pts characteristics: race: Caucasian- 61, African American-60, Asian-5; median age: 52.5 (range 26–84), stage I-32, II-34, III-18, IV-42. Results: Circulating GP88 was measurable in the serum. Median level of GP88 was 32.8 ng/ml (range 15.3–42.8) in HV and 43.8 ng/ml (range 15.4–158.4) in BC pts, (p-value = 0.0007). Conclusions: GP88 is measurable in the sera of HV and BC pts. Comparison between the two groups indicates that GP88 level is significantly higher in the sera of BC pts. These studies are important since it identifies GP88 as a measurable biomarker that is also a therapeutic target of malignant transformation or malignant progression of breast carcinoma (BC). Future studies will examine the correlation of GP88 level with BC prognostic factors. Correlation between the serum level of GP88 and therapeutic response to systemic therapy in breast cancer patients will also be assessed. [Table: see text]