Human chorionic gonadotropin β induces migration and invasion via activating ERK1/2 and MMP-2 in human prostate cancer DU145 cells

Direct DNA binding by BRCA1 on β-hCG promoter and its clinical implications

Objective

The role of β-hCG in breast cancer is largely unknown, this study aims to analyse the gene expression and clinical implications of β-hCG and its isoforms in various cancers focussing particularly in Breast Invasive Carcinoma (BRCA). A mechanistic approach deciphering the transcriptional regulation of β-hCG by BRCA1 was also explored.

Methods

Data from various comprehensive gene expression platforms like UALCAN, GEPIA2, GENT2, TIMER2, LinkedOmics, and STRING were used to analyse the expression of β-hCG and its clinical implications; Immunohistochemistry and ELISA for β-hCG expression analysis from human breast cancer patients; Electrophoretic mobility shift assay (EMSA) to analyse the direct binding of BRCA1 on β-hCG; Immunoblotting and Luciferase assay to understand the regulation of β-hCG by p53 were performed.

Results

Results from UALCAN and GENT2 gene expression cancer database revealed that TNBC subtypes and high-grade metaplastic carcinoma shows elevated expression of β-hCG and infiltration of various immune cells were also identified in BRCA by TIMER2. It was observed that most of the isoforms of β-hCG (CGB) are upregulated in breast cancers irrespective of hormonal status when BRCA1 gene is mutated according to TIMER2. Similar results were observed with Lymphoid neoplasm diffuse large B-cell lymphoma (LGG) and DLBC (Brain lower grade glioma) when BRCA1 is mutated. These results correlate with our earlier reports indicating expression of β-hCG in BRCA1 defective condition. We have also identified direct binding of BRCA1 on β-hCG promoter.

Conclusion

All these findings demonstrate the importance of β-hCG as a potential target in BRCA1-deficient carcinomas.

Aberrant trophoblastic differentiation in human cancer: An emerging novel therapeutic target (Review)

Various types of human cancer may develop aberrant trophoblastic differentiation, including histological changes and altered expression of β‑human chorionic gonadotropin (β‑hCG). Aberrant trophoblastic differentiation in epithelial cancer is usually associated with poor differentiation, tumor metastasis, unfavorable prognosis and treatment resistance. Since β‑hCG‑targeting vaccines have failed in an early phase II trial, it is crucial to obtain a better understanding of the molecular pathogenesis of trophoblastic differentiation in human cancer. The present review summarizes the clinical and translational research on this topic with the aim of accelerating the development of an effective targeted therapy. Ectopic expression of β‑hCG promotes proliferation, migration, invasion, vasculogenesis and epithelial‑mesenchymal transition (EMT) in vitro, and enhances metastatic and tumorigenic capabilities in vivo. Signaling cascades modulated by β‑hCG include the TGF‑β receptor pathway, EMT‑related pathways, the c‑MET receptor tyrosine kinase and mitogen‑activated protein kinase/ERK pathways, and the SMAD2/4 pathway. Taken together, these findings indicated that TGF‑β receptors, c‑MET and ERK1/2 are potential therapeutic targets. Nevertheless, further investigation on the molecular basis of aberrant trophoblastic differentiation is mandatory to improve the design of precision therapy for this aggressive type of human cancer.

ANGPTL4 regulates ovarian cancer progression by activating the ERK1/2 pathway

BACKGROUND

Ovarian cancer (OC) has the highest mortality rate among all gynecological malignancies. A hypoxic microenvironment is a common feature of solid tumors, including ovarian cancer, and an important driving factor of tumor cell survival and chemo- and radiotherapy resistance. Previous research identified the hypoxia-associated gene angiopoietin-like 4 (ANGPTL4) as both a pro-angiogenic and pro-metastatic factor in tumors. Hence, this work aimed to further elucidate the contribution of ANGPTL4 to OC progression.

METHODS

The expression of hypoxia-associated ANGPTL4 in human ovarian cancer was examined by bioinformatics analysis of TCGA and GEO datasets. The CIBERSORT tool was used to analyze the distribution of tumor-infiltrating immune cells in ovarian cancer cases in TCGA. The effect of ANGPTL4 silencing and overexpression on the proliferation and migration of OVCAR3 and A2780 OC cells was studied in vitro, using CCK-8, colony formation, and Transwell assays, and in vivo, through subcutaneous tumorigenesis assays in nude mice. GO enrichment analysis and WGCNA were performed to explore biological processes and genetic networks associated with ANGPTL4. The results obtained were corroborated in OC cells in vitro by western blotting.

RESULTS

Screening of hypoxia-associated genes in OC-related TCGA and GEO datasets revealed a significant negative association between ANGPTL4 expression and patient survival. Based on CIBERSORT analysis, differential representation of 14 distinct tumor-infiltrating immune cell types was detected between low- and high-risk patient groups. Silencing of ANGPTL4 inhibited OVCAR3 and A2780 cell proliferation and migration in vitro and reduced the growth rate of xenografted OVCAR3 cells in vivo. Based on results from WGCNA and previous studies, western blot assays in cultured OC cells demonstrated that ANGPTL4 activates the Extracellular signal-related kinases 1 and 2 (ERK1/2) pathway and this results in upregulation of c-Myc, Cyclin D1, and MMP2 expression. Suggesting that the above mechanism mediates the pro-oncogenic actions of ANGPTL4T in OC, the pro-survival effects of ANGPTL4 were largely abolished upon inhibition of ERK1/2 signaling with PD98059.

CONCLUSIONS

Our work suggests that the hypoxia-associated gene ANGPTL4 stimulates OC progression through activation of the ERK1/2 pathway. These findings may offer a new prospect for targeted therapies for the treatment of OC.

Cellular Functions of High-Temperature Requirement Factor A4 in Placenta

The expression of High-temperature requirement factor A4 (HtrA4) mRNA is significantly lower in the chorionic villi of patients with recurrent pregnancy loss (RPL) than in the control group. We conducted an investigation into the cellular functions of HtrA4 using the CRISPR/Cas9 system and shRNA-HtrA4 to create knockout BeWo cells and HtrA4 knockdown JEG3 cells. Our results indicated that the knockout BeWo cells exhibited reduced capacity for invasion and fusion, but increased levels of proliferation and migration, with a significantly shortened cell cycle compared to wild-type cells. Wild-type BeWo cells highly expressed cell invasion- and fusion-related factors, while knockout BeWo cells highly expressed migration-, proliferation-, and cell cycle-related factors. The shRNA-HtrA4 JEG3 cells showed a decreased capacity for invasion, but an increased capacity for migration, accompanied by a decrease in the expression of cell invasion-related factors and an increase in migration-related factors. Moreover, our ELISA results revealed that the serum HtrA4 level was lower in patients with RPL than in the controls. These findings suggest that HtrA4 depletion may be associated with placental dysfunction.

Endocrine and paracrine characteristics of neuroendocrine prostate cancer

Prostate cancer is a common malignancy affecting men worldwide. While the vast majority of newly diagnosed prostate cancers are categorized as adenocarcinomas, a spectrum of uncommon tumor types occur including those with small cell and neuroendocrine cell features. Benign neuroendocrine cells exist in the normal prostate microenvironment, and these cells may give rise to primary neuroendocrine carcinomas. However, the more common development of neuroendocrine prostate cancer is observed after therapeutics designed to repress the signaling program regulated by the androgen receptor which is active in the majority of localized and metastatic adenocarcinomas. Neuroendocrine tumors are identified through immunohistochemical staining for common markers including chromogranin A/B, synaptophysin and neuron specific enolase (NSE). These markers are also common to neuroendocrine tumors that arise in other tissues and organs such as the gastrointestinal tract, pancreas, lung and skin. Notably, neuroendocrine prostate cancer shares biochemical features with nerve cells, particularly functions involving the secretion of a variety of peptides and proteins. These secreted factors have the potential to exert local paracrine effects, and distant endocrine effects that may modulate tumor progression, invasion, and resistance to therapy. This review discusses the spectrum of factors derived from neuroendocrine prostate cancers and their potential to influence the pathophysiology of localized and metastatic prostate cancer.

Comprehensive analysis of regulation of DNA methyltransferase isoforms in human breast tumors

Significant reprogramming of epigenome is widely described during pathogenesis of breast cancer. Transformation of normal cell to hyperplastic cell and to neoplastic phenotype is associated with aberrant DNA (de)methylation, which, through promoter and enhancer methylation changes, activates oncogenes and silence tumor suppressor genes in variety of tumors including breast. DNA methylation, one of the major epigenetic mechanisms is catalyzed by evolutionarily conserved isoforms namely, DNMT1, DNMT3A and DNMT3B in humans. Over the years, studies have demonstrated intricate and complex regulation of DNMT isoforms at transcriptional, translational and post-translational levels. The recent findings of allosteric regulation of DNMT isoforms and regulation by other interacting chromatin modifying proteins emphasizes functional integrity and their contribution for the development of breast cancer and progression. DNMT isoforms are regulated by several intrinsic and extrinsic parameters. In the present review, we have extensively performed bioinformatics analysis of expression of DNMT isoforms along with their transcriptional and post-transcriptional regulators such as transcription factors, interacting proteins, hormones, cytokines and dietary elements along with their significance during pathogenesis of breast tumors. Our review manuscript provides a comprehensive understanding of key factors regulating DNMT isoforms in breast tumor pathology and documents unsolved issues.

Unconventional Actions of Glycoprotein Hormone Subunits: A Comprehensive Review

The glycoprotein hormones (GPH) are heterodimers composed of a common α subunit and a specific β subunit. They act by activating specific leucine-rich repeat G protein-coupled receptors. However, individual subunits have been shown to elicit responses in cells devoid of the receptor for the dimeric hormones. The α subunit is involved in prolactin production from different tissues. The human chorionic gonadotropin β subunit (βhCG) plays determinant roles in placentation and in cancer development and metastasis. A truncated form of the thyrotropin (TSH) β subunit is also reported to have biological effects. The GPH α- and β subunits are derived from precursor genes (gpa and gpb, respectively), which are expressed in most invertebrate species and are still represented in vertebrates as GPH subunit paralogs (gpa2 and gpb5, respectively). No specific receptor has been found for the vertebrate GPA2 and GPB5 even if their heterodimeric form is able to activate the TSH receptor in mammals. Interestingly, GPA and GPB are phylogenetically and structurally related to cysteine-knot growth factors (CKGF) and particularly to a group of antagonists that act independently on any receptor. This review article summarizes the observed actions of individual GPH subunits and presents the current hypotheses of how these actions might be induced. New approaches are also proposed in light of the evolutionary relatedness with antagonists of the CKGF family of proteins.

β-hCG-induced mutant BRCA1 ignites drug resistance in susceptible breast tissue

β-hCG expression in breast cancer is highly controversial with reports supporting both protective and tumorigenic effects. It has also been reported that risk of breast cancer at an early age is increased with full-term pregnancies if a woman is a BRCA1 mutation carrier. We have already demonstrated that BRCA1-defective cells express high levels of β-hCG and that when BRCA1 is restored, β-hCG level is reduced. Also, BRCA1 can bind to the promoter and reduce the levels of β-hCG. β-hCG induces tumorigenicity in BRCA1-defective cells by directly binding to TGFBRII and induces TGFBRII-mediated cell proliferation. In this study, we analyzed the mechanism of action of β-hCG on BRCA1 expression and its influence on drug sensitivity in breast cancer cells. We demonstrate that β-hCG induces mutant BRCA1 protein expression in BRCA1 mutant cells; however, in BRCA1 wild-type cells, β-hCG reduced wild-type BRCA1 protein expression. Transcriptionally, β-hCG could induce Slug/LSD1-mediated repression of wild-type and mutant BRCA1 messenger RNA levels. However, β-hCG induces HSP90-mediated stabilization of mutant BRCA1 and hence the overexpression of mutant BRCA1 protein, resulting in partial restoration of homologous recombination repair of damaged DNA. This contributes to drug resistance to HSP90 inhibitor 17AAG in BRCA1-defective cancer cells. A combination of HSP90 inhibitor and TGFBRII inhibitor has shown to sensitize β-hCG expressing BRCA1-defective breast cancers to cell death. Targeting the β-hCG-HSP90-TGFBRII axis could prove an effective treatment strategy for BRCA1-mutated breast tumors.

Apoptosis Induction of Fibroblast-Like Synoviocytes Is an Important Molecular-Mechanism for Herbal Medicine along with its Active Components in Treating Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a known chronic autoimmune disease can cause joint deformity and even loss of joint function. Fibroblast-like synoviocytes (FLS), one of the main cell types in synovial tissues of RA patients, are key effector cells in the development of RA and are considered as promising therapeutic targets for treating RA. Herbal medicines are precious resources for finding novel agents for treating various diseases including RA. It is reported that induction of apoptosis in FLS is an important mechanism for the herbal medicines to treat RA. Consequently, this paper reviewed the current available references on pro-apoptotic effects of herbal medicines on FLS and summarized the related possible signal pathways. Taken together, the main related signal pathways are concluded as death receptors mediated apoptotic pathway, mitochondrial dependent apoptotic pathway, NF-κB mediated apoptotic pathways, mitogen-activated protein kinase (MAPK) mediated apoptotic pathway, endoplasmic reticulum stress (ERS) mediated apoptotic pathway, PI3K-Akt mediated apoptotic pathway, and other reported pathways such as janus kinase/signal transducers and activators of transcription (JAK-STAT) signal pathway. Understanding the apoptosis induction pathways in FLS of these herbal medicines will not only help clear molecular mechanisms of herbal medicines for treating RA but also be beneficial for finding novel candidate therapeutic drugs from natural herbal medicines. Thus, we expect the present review will highlight the importance of herbal medicines and its components for treating RA via induction of apoptosis in FLS, and provide some directions for the future development of these mentioned herbal medicines as anti-RA drugs in clinical.

β-hCG promotes epithelial ovarian cancer metastasis through ERK/MMP2 signaling pathway

Epithelial ovarian cancer (EOC) is the most lethal gynecologic malignancy, with typically extensive intraperitoneal implantation leading to poor prognosis. Our previous study preliminarily demonstrated β-hCG can promote tumorigenesis in immortalized nontumorigenic ovarian epithelial cells. In this study, the roles and mechanisms of β-hCG in regulating EOC proliferation and metastasis were thoroughly explored. First, histologically, β-hCG was aberrantly overexpressed in human EOC metastatic tissues, and significantly correlated with FIGO stage, tumor size, differentiation, histologic grade and high grade serous ovarian carcinoma (HGSOC) (P < 0.05). However, serologically, β-hCG expression showed no significant difference between EOC and nonmalignant ovarian patients. Second, β-hCG was confirmed to have no significant effects on EOC proliferation in vitro and in vivo, while β-hCG upregulation was proven to promote migration and invasion ability in ES-2 and OVCAR-3 cells in vitro (P < 0.05), and β-hCG downregulation in SKOV3 cells had the opposite effect. Moreover, more invadopodia protrusions, mitochondria accumulations and cytoskeletal rearrangements were observed in β-hCG-overexpressing ES-2 cells, while β-hCG-depleted SKOV3 cells produced the opposite effect. Furthermore, β-hCG was confirmed to clearly facilitate intraperitoneal metastasis in nude mouse orthotopic ovarian xenograft models. Importantly, these effects of β-hCG were mediated by activation of the ERK/MMP2 signaling pathway, independently of luteinizing hormone/chorionic gonadotropin receptor (LHCGR) presence, and inhibition the pathway with the p-ERK1/2 inhibitor SCH772984 significantly impaired the tumor-promoting effects induced by β-hCG. Collectively, these data provide new insight into the roles and mechanisms of β-hCG in regulating EOC metastasis through ERK/MMP2 signaling pathway and may become a new target for therapeutic intervention.

Sulforaphane from Cruciferous Vegetables: Recent Advances to Improve Glioblastoma Treatment

Sulforaphane (SFN), an isothiocyanate (ITC) derived from cruciferous vegetables, particularly broccoli and broccoli sprouts, has been widely investigated due to its promising health-promoting properties in disease, and low toxicity in normal tissue. Although not yet fully understood, many mechanisms of anticancer activity at each step of cancer development have been attributed to this ITC. Given the promising data available regarding SFN, this review aimed to provide an overview on the potential activities of SFN related to the cellular mechanisms involved in glioblastoma (GBM) progression. GBM is the most frequent malignant brain tumor among adults and is currently an incurable disease due mostly to its highly invasive phenotype, and the poor efficacy of the available therapies. Despite all efforts, the median overall survival of GBM patients remains approximately 1.5 years under therapy. Therefore, there is an urgent need to provide support for translating the progress in understanding the molecular background of GBM into more complex, but promising therapeutic strategies, in which SFN may find a leading role.

HOXB7 overexpression promotes cell proliferation and correlates with poor prognosis in gastric cancer patients by inducing expression of both AKT and MARKs

Increased expression of HOXB7 has been reported to correlate with the progression in many cancers. However, the specific mechanism by which it promotes the evolution of gastric cancer (GC) is poorly understood.In this study, we sought to investigate the role of HOXB7 in GC by assessing HOXB7 expression in patient tissue and its correlation to clinical characteristics. We found that GC tissues showed increased expression of HOXB7 and that the HOXB7 expression was significantly associated with Lauren classification, invasion depth, lymphatic metastasis and poor prognosis, and could serve as an independent prognostic factor. To further investigate the role of HOXB7 in GC, we generated stable GC cell lines and both over-expressed and knocked down HOXB7 expression. Over-expression of HOXB7 in GC cell lines enhanced cell proliferation, colony formation, migration and invasion ability, whereas the opposite trends were observed upon reduction of HOXB7 expression by knockdown. These findings were further supported by our in vivo studies which show that HOXB7 expression can affect the GC cells' subcutaneous growth and lung metastases. A Phospho-MAPK Array Kit was used to explore the possible mechanism of HOXB7-induced cell proliferation and invasion. We found that the AKT signaling pathway and the two members of the MAPK pathway, were involved in those promoting effects. In conclusion, our results showed that increased expression of HOXB7 might play an important role in promoting GC proliferation, migration and invasion by inducing both AKT and MAPK pathways, thus resulting in progression of, and poor prognosis in GC patients.

miR-143-3p regulates cell proliferation and apoptosis by targeting IGF1R and IGFBP5 and regulating the Ras/p38 MAPK signaling pathway in rheumatoid arthritis

It has been demonstrated that the deregulation of microRNAs (miRNAs) affects the development of rheumatoid arthritis (RA). The primary objective of the current study was to determine the role of miR-143-3p in the progression of RA. The expression of miR-143-3p in synovium taken from patients with RA was assessed by reverse transcription-quantitative polymerase chain reaction. The expression of miR-143-3p was higher in synovium tissues of RA than that of osteoarthritis (OA). The decreased expression of miR-143-3p suppressed cell proliferation and promoted apoptosis in vitro. In addition, inhibition of miR-143-3p decreased levels of inflammatory cytokines, as determined by an enzyme-linked immunosorbent assay. IGF1R and IGFBP5 were found to be the target genes of miR-143-3p, and it was demonstrated that miR-143-3p regulated the proliferation and apoptosis of MH7A cells by targeting IGF1R and IGFBP5. Furthermore, TNF-α treatment stimulated the Ras/p38 mitogen activated protein kinase (MAPK) signaling pathway, whereas miR-143-3p inhibition suppressed it. The results of the current study indicate that miR-143-3p may regulate cell proliferation and apoptosis by targeting IGF1R and IGFBP5 expression and regulating the Ras/p38 MAPK signaling pathways. Therefore, miR-143-3p may be a novel therapeutic target in RA.

BRCA1 regulation on β-hCG: a mechanism for tumorigenicity in BRCA1 defective breast cancer

Human chorionic gonadotropin β (β-hCG) has been implicated in breast tumorigenesis. However, the role of this hormone is highly controversial as certain studies suggest it has anti-tumor properties while others have found it to be pro-tumorigenic. To unveil the truth, we have analyzed the expression of β-hCG in breast cancer. We identified for the first time that β-hCG expression is linked to BRCA1 status and its overexpression is seen in BRCA1 mutated breast cancer cells, BRCA1 conditional knockout mouse breast cancer tissues and BRCA1 floxed basal cell carcinoma (BCC) tissues. An analysis of three large, transcriptomic data sets from TCGA (The Cancer Genome Atlas) expression profile confirmed the inverse correlation between BRCA1 and β-hCG in human breast cancer. Using ChIP and luciferase assays, we also demonstrated that the cancer cells with wild-type but not mutant BRCA1 directly repress the expression of β-hCG by binding to its promoter. Further, β-hCG promotes migration and invasion predominantly in BRCA1 mutant breast cancer cells. Interestingly, stable overexpression of β-hCG in BRCA1 mutant but not wild-type breast cancer cells results in the formation of spheres even on monolayer cultures. The cells of these spheres show high expression of both EMT and stem cell markers. Since β-hCG belongs to a cysteine knot family of proteins like TGFβ and TGFβ signaling is deregulated in BRCA1 defective tumors, we checked whether β-hCG can mediate signaling through TGFβRII in BRCA1 mutated cells. We found for the first time that β-hCG can bind and phosphorylate TGFβRII, irrespective of LHCGR status and induce proliferation in BRCA1 defective cells. Our results confirmed that there exists a transcriptional regulation of BRCA1 on β-hCG and BRCA1 mutation promotes β-hCG mediated tumorigenesis through TGFβRII signaling. Thus inhibiting β-hCG-TGFβRII could prove an effective treatment strategy for BRCA1 mutated tumors.

Human Chorionic Gonadotropin and Breast Cancer

Breast cancer is well known as a malignancy being strongly influenced by female steroids. Pregnancy is a protective factor against breast cancer. Human chorionic gonadotropin (HCG) is a candidate hormone which could mediate this antitumoral effect of pregnancy. For this review article, all original research articles on the role of HCG in breast cancer were considered, which are listed in PubMed database and were written in English. The role of HCG in breast cancer seems to be a paradox. Placental heterodimeric HCG acts as a protective agent by imprinting a permanent genomic signature of the mammary gland determining a refractory condition to malignant transformation which is characterized by cellular differentiation, apoptosis and growth inhibition. On the other hand, ectopic expression of β-HCG in various cancer entities is associated with poor prognosis due to its tumor-promoting function. Placental HCG and ectopically expressed β-HCG exert opposite effects on breast tumorigenesis. Therefore, mimicking pregnancy by treatment with HCG is suggested as a strategy for breast cancer prevention, whereas targeting β-HCG expressing tumor cells seems to be an option for breast cancer therapy.

Maternal-fetal conflict, genomic imprinting and mammalian vulnerabilities to cancer

Antagonistic coevolution between maternal and fetal genes, and between maternally and paternally derived genes may have increased mammalian vulnerability to cancer. Placental trophoblast has evolved to invade maternal tissues and evade structural and immunological constraints on its invasion. These adaptations can be co-opted by cancer in intrasomatic selection. Imprinted genes of maternal and paternal origin favour different degrees of proliferation of particular cell types in which they reside. As a result, the set of genes favouring greater proliferation will be selected to evade controls on cell-cycle progression imposed by the set of genes favouring lesser proliferation. The dynamics of stem cell populations will be a particular focus of this intragenomic conflict. Gene networks that are battlegrounds of intragenomic conflict are expected to be less robust than networks that evolve in the absence of conflict. By these processes, maternal-fetal and intragenomic conflicts may undermine evolved defences against cancer.

Increased nuclear stiffness via FAK-ERK1/2 signaling is necessary for synthetic mechano-growth factor E peptide-induced tenocyte migration

We have previously reported that a synthetic mechano-growth factor (MGF) C-terminal E-domain with 25 amino acids (MGF-C25E) promotes rat tenocyte migration through the FAK-ERK1/2 signaling pathway. However, the role of the nucleus in MGF-C25E-promoted tenocyte migration and the molecular mechanisms involved remain unclear. In this study, we demonstrate that MGF-C25E increases the Young’s modulus of tenocytes through the FAK-ERK1/2 signaling pathway. This increase is not accompanied by an obvious change in the expression of Lamin A/C but is accompanied by significant chromatin condensation, indicating that MGF-C25E-induced chromatin condensation may contribute to the increased nuclear stiffness. Moreover, DNA methylation is observed in MGF-C25E-treated tenocytes. Inhibition of DNA methylation suppresses the elevation in chromatin condensation, in nuclear stiffness, and in tenocyte migration induced by MGF-C25E. The inhibition of the focal adhesion kinase (FAK) or extracellular signal regulated kinase 1/2 (ERK1/2) signals represses MGF-C25E-promoted DNA methylation. It also abolishes chromatin condensation, nuclear stiffness, and cell migration. Taken together, our results suggest that MGF-C25E promotes tenocyte migration by increasing nuclear stiffness via the FAK-ERK1/2 signaling pathway. This provides strong evidence for the role of nuclear mechanics in tenocyte migration and new insight into the molecular mechanisms of MGF-promoted tenocyte migration.

Hepatosplenic T-cell lymphoma with aberrant expression of serum β-HCG: a case report

BACKGROUND

Peripheral T-cell lymphomas (PTCL) represent a heterogeneous group of hematologic malignancies frequently presenting at advanced stage of diagnosis.

METHODS

We report a case of PTCL with an uncommon and aggressive onset with disseminated intravascular coagulation (DIC).

RESULTS

Laboratory findings revealed an aberrant expression of β subunit of human chorionic gonadotropin (β-HCG). Other than for determination of pregnancy, β-HCG is regularly found as a tumor marker in germ cell tumors with trophoblastic differentiation and its aberrant expression has been reported in the literature in other neoplastic conditions only in the context of case reports.

CONCLUSIONS

In hematologic malignancies, β-HCG expression has been described only in sporadic cases. Awareness of this feature could avoid diagnostic delay in such an aggressive disease.

Sulforaphane inhibits invasion by phosphorylating ERK1/2 to regulate E-cadherin and CD44v6 in human prostate cancer DU145 cells

Advanced prostate cancer has highly invasive potential, which may lead to metastasis associated with poor prognosis. Sulforaphane (SFN), abundant in cruciferous vegetables, exhibited effective resistance to carcinogenesis in a variety of tumors. The aim of the present study was to investigate whether SFN inhibited invasion in human prostate cancer cells via sustained activation of ERK1/2 and downstream signaling by an invasion assay, gelatin zymography and western blot analysis. The results showed that SFN inhibited invasion and we characterized the underlying mechanisms in human DU145 prostate cancer cells. SFN (15 µM) changed cell morphology leading to short‑cell pseudopodia which may suppress tumor migration and invasion. The Transwell assay showed that SFN phosphorylated ERK1/2 in a dose- and time-dependent manner and significantly inhibited cell invasion, while the effect was reduced by the ERK1/2 blocker PD98059 (25 µM). Furthermore, these effects contributed to the upregulation of E-cadherin and the downregulation of CD44v6 and were eradicated by PD98059. Western blot analysis and gelatin zymography showed that SFN decreased the expression and activity of MMP-2. Thus, SFN inhibited invasion by activating ERK1/2 to upregulate E-cadherin and downregulate CD44v6, thereby reducing MMP-2 expression and activity. E-cadherin is an invasion inhibitor, while CD44v6 and MMP-2 are invasion promoters. Therefore, SFN is a prospective therapeutic agent that may be used to prevent invasion in prostate cancer.

MGF enhances tenocyte invasion through MMP-2 activity via the FAK-ERK1/2 pathway

Tendon regeneration and healing requires tenocytes to move to the repair site followed by proliferation and synthesis of the extracellular matrix. A novel synthetic growth factor, mechano-growth factor (MGF), has been discovered to have positive roles in tissue repair through the improvement of cell proliferation and migration and the protection of cells against injury-induced apoptosis. However, it remains unclear whether MGF has the potential to accelerate tendon repair. In this study, using a transwell system, we found that MGF-C25E (a synthetic mechano-growth factor E peptide) significantly promotes tenocyte invasion, which was accompanied by the increased phosphorylation of focal adhesion kinase (FAK) and extracellular signal regulated kinase1/2 (ERK1/2) as well as the increased activity of matrix metalloproteinases-2 (MMP-2). The MMP-2 inhibitor OA-Hy blocked MGF-C25E-promoted tenocyte invasion. Inhibitors of FAK or ERK1/2 blocked MGF-C25E-promoted tenocyte invasion and MMP-2 activity as well. These results indicate that MGF-C25E promotes tenocyte invasion by increasing MMP-2 activity via the FAK-ERK1/2 signaling pathway. Taken together, our findings provide the first evidence that MGF-C25E enhances tenocyte invasion and indicate that it may serve as a potential repair material for promoting the healing and regeneration of injured tendons.

Cyclic mechanical stretching promotes migration but inhibits invasion of rat bone marrow stromal cells

Bone marrow stromal cells (BMSCs, also broadly known as bone marrow-derived mesenchymal stem cells) are multipotent stem cells that have a self-renewal capacity and multilineage differentiation potential. Mechanical stretching plays a vital role in regulating the proliferation and differentiation of BMSCs. However, little is known about the effects of cyclic stretching on BMSC migration and invasion. In this study, using a custom-made cell-stretching device, we studied the effects of cyclic mechanical stretching on rat BMSC migration and invasion using a Transwell Boyden Chamber. The protein secretion of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) was detected by gelatin zymography, and the activation of focal adhesion kinase (FAK) and extracellular signal regulated kinase1/2 (ERK1/2) was measured by western blot. We found that cyclic mechanical stretching with 10% amplitude at 1Hz frequency for 8h promotes BMSC migration, but reduces BMSC invasion. FAK and ERK1/2 signals were activated in BMSCs after exposure to cyclic stretching. In the presence of the FAK phosphorylation blocker PF573228 or the ERK1/2 phosphorylation blocker PD98059, the cyclic-stretch-promoted migration of BMSCs was completely suppressed. On the other hand, cyclic mechanical stretching reduced the secretion of MMP-2 and MMP-9 in BMSCs, and PF573228 suppressed the cyclic-stretch-reduced secretion of MMP-2 and MMP-9. The decrease of BMSC invasion induced by mechanical stretching is partially restored by PF573228 but remained unaffected by PD98059. Taken together, these data show that cyclic mechanical stretching promotes BMSC migration via the FAK-ERK1/2 signalling pathway, but reduces BMSC invasion by decreasing secretion of MMP-2 and MMP-9 via FAK, independent of the ERK1/2 signal.

TGF-β-induced hCG-β regulates redox homeostasis in glioma cells

Transforming growth factor (TGF-β) is associated with the progression of glioblastoma multiforme (GBM)-the most malignant of brain tumors. Since there is a structural homology between TGF-β and human chorionic gonadotropin (hCG) and as both TGF-β and hCG-β are known regulators of oxidative stress and survival responses in a variety of tumors, the role of TGF-β in the regulation of hCG-β and its consequences on redox modulation of glioblastoma cells was investigated. A heightened hCG-β level was observed in GBM tumors. TGF-β treatment increased hCG-β expression in glioma cell lines, and this heightened hCG-β was found to regulate redox homeostasis in TGF-β-treated glioma cells, as siRNA-mediated knockdown of hCG-β (i) elevated reactive oxygen species (ROS) generation, (ii) decreased thioredoxin Trx1 expression and thioredoxin reductase (TrxR) activity, and (iii) abrogated expression of TP53-induced glycolysis and apoptosis regulator (TIGAR). Silencing of hCG-β abrogated Smad2/3 levels, suggesting the existence of TGF-β-hCG-β cross-talk in glioma cells. siRNA-mediated inhibition of elevated TIGAR levels in TGF-β-treated glioma cells was accompanied by an increase in ROS levels. As a farnesyltransferase inhibitor, Manumycin is known to induce glioma cell apoptosis in a ROS-dependent manner, and we investigated whether Manumycin could induce apoptosis in TGF-β-treated cells with elevated hCG-β exhibiting ROS-scavenging property. Manumycin-induced apoptosis in TGF-β-treated cells was accompanied by elevated ROS levels and decreased expression of hCG-β, Trx1, Smad2/3, and TIGAR. These findings indicate the existence of a previously unknown TGF-β-hCG-β link that regulates redox homeostasis in glioma cells.

NR4A1 promotes PDGF-BB-induced cell colony formation in soft agar

The fibroblast mitogen platelet-derived growth factor -BB (PDGF-BB) induces a transient expression of the orphan nuclear receptor NR4A1 (also named Nur77, TR3 or NGFIB). The aim of the present study was to investigate the pathways through which NR4A1 is induced by PDGF-BB and its functional role. We demonstrate that in PDGF-BB stimulated NIH3T3 cells, the MEK1/2 inhibitor CI-1040 strongly represses NR4A1 expression, whereas Erk5 downregulation delays the expression, but does not block it. Moreover, we report that treatment with the NF-κB inhibitor BAY11-7082 suppresses NR4A1 mRNA and protein expression. The majority of NR4A1 in NIH3T3 was found to be localized in the cytoplasm and only a fraction was translocated to the nucleus after continued PDGF-BB treatment. Silencing NR4A1 slightly increased the proliferation rate of NIH3T3 cells; however, it did not affect the chemotactic or survival abilities conferred by PDGF-BB. Moreover, overexpression of NR4A1 promoted anchorage-independent growth of NIH3T3 cells and the glioblastoma cell lines U-105MG and U-251MG. Thus, whereas NR4A1, induced by PDGF-BB, suppresses cell growth on a solid surface, it increases anchorage-independent growth.

Src-homology 2 domain-containing tyrosine phosphatase 2 promotes oral cancer invasion and metastasis

Background

Tumor invasion and metastasis represent a major unsolved problem in cancer pathogenesis. Recent studies have indicated the involvement of Src-homology 2 domain-containing tyrosine phosphatase 2 (SHP2) in multiple malignancies; however, the role of SHP2 in oral cancer progression has yet to be elucidated. We propose that SHP2 is involved in the progression of oral cancer toward metastasis.

Methods

SHP2 expression was evaluated in paired oral cancer tissues by using immunohistochemical staining and real-time reverse transcription polymerase chain reaction. Isogenic highly invasive oral cancer cell lines from their respective low invasive parental lines were established using a Boyden chamber assay, and changes in the hallmarks of the epithelial-mesenchymal transition (EMT) were assessed to evaluate SHP2 function. SHP2 activity in oral cancer cells was reduced using si-RNA knockdown or enforced expression of a catalytically deficient mutant to analyze migratory and invasive ability in vitro and metastasis toward the lung in mice in vivo.

Results

We observed the significant upregulation of SHP2 in oral cancer tissues and cell lines. Following SHP2 knockdown, the oral cancer cells markedly attenuated migratory and invasion ability. We observed similar results in phosphatase-dead SHP2 C459S mutant expressing cells. Enhanced invasiveness was associated with significant upregulation of E-cadherin, vimentin, Snail/Twist1, and matrix metalloproteinase-2 in the highly invasive clones. In addition, we determined that SHP2 activity is required for the downregulation of phosphorylated ERK1/2, which modulates the downstream effectors, Snail and Twist1 at a transcript level. In lung tissue sections of mice, we observed that HSC3 tumors with SHP2 deletion exhibited significantly reduced metastatic capacity, compared with tumors administered control si-RNA.

Conclusions

Our data suggest that SHP2 promotes the invasion and metastasis of oral cancer cells. These results provide a rationale for further investigating the effects of small-molecule SHP2 inhibitors on the progression of oral cancer, and indicate a previously unrecognized SHP2-ERK1/2-Snail/Twist1 pathway that is likely to play a crucial role in oral cancer invasion and metastasis.

Sulforaphane inhibits invasion via activating ERK1/2 signaling in human glioblastoma U87MG and U373MG cells

BACKGROUND

Glioblastoma has highly invasive potential, which might result in poor prognosis and therapeutic failure. Hence, the key we study is to find effective therapies to repress migration and invasion. Sulforaphane (SFN) was demonstrated to inhibit cell growth in a variety of tumors. Here, we will further investigate whether SFN inhibits migration and invasion and find the possible mechanisms in human glioblastoma U87MG and U373MG cells.

METHODS

First, the optimal time and dose of SFN for migration and invasion study were determined via cell viability and cell morphological assay. Further, scratch assay and transwell invasion assay were employed to investigate the effect of SFN on migration and invasion. Meanwhile, Western blots were used to detect the molecular linkage among invasion related proteins phosphorylated ERK1/2, matrix metalloproteinase-2 (MMP-2) and CD44v6. Furthermore, Gelatin zymography was performed to detect the inhibition of MMP-2 activation. In addition, ERK1/2 blocker PD98059 (25 µM) was integrated to find the link between activated ERK1/2 and invasion, MMP-2 and CD44v6.

RESULTS

The results showed that SFN (20 µM) remarkably reduced the formation of cell pseudopodia, indicating that SFN might inhibit cell motility. As expected, scratch assay and transwell invasion assay showed that SFN inhibited glioblastoma cell migration and invasion. Western blot and Gelatin zymography showed that SFN phosphorylated ERK1/2 in a sustained way, which contributed to the downregulated MMP-2 expression and activity, and the upregulated CD44v6 expression. These molecular interactions resulted in the inhibition of cell invasion.

CONCLUSIONS

SFN inhibited migration and invasion processes. Furthermore, SFN inhibited invasion via activating ERK1/2 in a sustained way. The accumulated ERK1/2 activation downregulated MMP-2 expression and decreased its activity and upregulated CD44v6. SFN might be a potential therapeutic agent by activating ERK1/2 signaling against human glioblastoma.

Baicalein inhibits the invasion and metastatic capabilities of hepatocellular carcinoma cells via down-regulation of the ERK pathway

Baicalein, a widely used Chinese herbal medicine, has historically been used in anti-inflammatory and anti-cancer therapies. However, the anti-metastatic effect and molecular mechanism(s) of baicalein on hepatocellular carcinoma (HCC) remain poorly understood. Therefore, the purpose of this study was to assess the anti-metastatic effects of baicalein and related mechanism(s) on HCC. Based on assays utilized in both HCC cell lines and in an animal model, we found that baicalein inhibited tumor cell metastasis in vivo and in vitro. Furthermore, after treatment with baicalein for 24 hours, there was a decrease in the levels of matrix metalloproteinase-2 (MMP-2), MMP-9 and urokinase-type plasminogen activator (u-PA) expression as well as proteinase activity in hepatocellular carcinoma MHCC97H cells. Meanwhile, the expression of tissue inhibitor of metalloproteinase-1 (TIMP-1) and TIMP-2 were increased in a dose-dependent fashion. Moreover, baicalein treatment dramatically decreased the levels of the phosphorylated forms of MEK1 and ERK1/2. MEK1 overexpression partially blocked the anti-metastatic effects of baicalein. Combined treatment with an ERK inhibitor (U0126) and baicalein resulted in a synergistic reduction in MMP-2, MMP-9 and u-PA expression and an increase in TIMP-1 and TIMP-2 expression; the invasive capabilities of MHCC97H cells were also inhibited. In conclusion, baicalein inhibits tumor cell invasion and metastasis by reducing cell motility and migration via the suppression of the ERK pathway, suggesting that baicalein is a potential therapeutic agent for HCC.