Hypoxia-induced TREM1 promotes mesenchymal-like states of glioma stem cells via alternatively activating tumor-associated macrophages.

The mesenchymal subtype of glioblastoma (GBM) cells characterized by aggressive invasion and therapeutic resistance is thought to be dependent on cell-intrinsic alteration and extrinsic cellular crosstalk. Tumor-associated macrophages (TAMs) are pivotal in tumor progression, chemo-resistance, angiogenesis, and stemness maintenance. However, the impact of TAMs on the shifts in glioma stem cells (GSCs) states remains largely uncovered. Herein, we showed that the triggering receptor expressed on myeloid cells-1 (TREM1) preferentially expressed by M2-like TAMs and induced GSCs into mesenchymal-like states by modulating the secretion of TGFß2, which activated the TGFßR/SMAD2/3 signaling in GSCs. Furthermore, we demonstrated that TREM1 was transcriptionally regulated by HIF1a under the hypoxic environment and thus promoted an immunosuppressive type of TAMs via activating the TLR2/AKT/mTOR/c-MYC axis. Collectively, this study reveals that cellular communication between TAMs and GSCs through the TREM1-mediated TGFß2/TGFßR axis is involved in the mesenchymal-like transitions of GSCs. Our study provides valuable insights into the regulatory mechanisms between the tumor immune microenvironment and the malignant characteristics of GBM, which can lead to potential novel strategies targeting TAMs for tumor control.

Transgelin Promotes Glioblastoma Stem Cell Hypoxic Responses and Maintenance Through p53 Acetylation.

Glioblastoma (GBM) is a lethal cancer characterized by hypervascularity and necrosis associated with hypoxia. Here, it is found that hypoxia preferentially induces the actin-binding protein, Transgelin (TAGLN), in GBM stem cells (GSCs). Mechanistically, TAGLN regulates HIF1α transcription and stabilizes HDAC2 to deacetylate p53 and maintain GSC self-renewal. To translate these findings into preclinical therapeutic paradigm, it is found that sodium valproate (VPA) is a specific inhibitor of TAGLN/HDAC2 function, with augmented efficacy when combined with natural borneol (NB) in vivo. Thus, TAGLN promotes cancer stem cell survival in hypoxia and informs a novel therapeutic paradigm.

FAM129A promotes self-renewal and maintains invasive status via stabilizing the Notch intracellular domain in glioma stem cells.

BACKGROUND: Glioma stem cells (GSCs) are a subpopulation of tumor cells with self-renewal and tumorigenic capabilities in glioblastomas (GBMs). Diffuse infiltration of GSCs facilitates tumor progression and frustrates efforts at effective treatment. Further compounding this situation is the currently limited understanding of what drives GSC invasion. Here we comprehensively evaluated the significance of a novel invasion-related protein, Family with Sequence Similarity 129 Member A (FAM129A), in infiltrative GSCs. METHODS: Western blotting, immunohistochemistry, and gene expression analysis were used to quantify FAM129A in glioma specimens and cancer datasets. Overexpression and knockdown of FAM129A in GSCs were used to investigate its effects on tumor growth and invasion. RNA-seq, qRT-PCR, western blotting, and co-precipitation assays were used to investigate FAM129A signaling mechanisms. RESULTS: FAM129A is preferentially expressed in invasive frontiers. Targeting FAM129A impairs GSC invasion and self-renewal. Mechanistically, FAM129A acted as a positive regulator of Notch signaling by binding with the Notch1 intracellular domain (NICD1) and preventing its degradation. CONCLUSIONS: FAM129A and NICD1 provide a precise indicator for identifying tumor margins and aiding prognosis. Targeting them may provide a significantly therapeutic strategy for GSCs.

LRIG2 promotes glioblastoma progression by modulating innate antitumor immunity through macrophage infiltration and polarization.

BACKGROUND: Glioblastoma (GBM) is the most common malignant brain tumor with poor clinical outcomes. Immunotherapy has recently been an attractive and promising treatment of extracranial malignancies, however, most of clinical trials for GBM immunotherapy failed due to predominant accumulation of tumor-associated microglia/macrophages (TAMs). RESULTS: High level of LRIG2/soluble LRIG2 (sLRIG2) expression activates immune-related signaling pathways, which are associated with poor prognosis in GBM patients. LRIG2/sLRIGs promotes CD47 expression and facilitates TAM recruitment. Blockade of CD47-SIRPα interactions and inhibition of sLRIG2 secretion synergistically suppress GBM progression in an orthotropic murine GBM model. CONCLUSIONS: GBM cells with high level LRIG2 escape the phagocytosis by TAM via the CD47-SIRPα axis, highlighting a necessity for an early stage of clinical trial targeting LRIG2 and CD47-SIRPα as a novel treatment for patients with GBM.

Hypoxia-induced HMGB1 promotes glioma stem cells self-renewal and tumorigenicity via RAGE.

Glioma stem cells (GSCs) in the hypoxic niches contribute to tumor initiation, progression, and recurrence in glioblastoma (GBM). Hypoxia induces release of high-mobility group box 1 (HMGB1) from tumor cells, promoting the development of tumor. Here, we report that HMGB1 is overexpressed in human GBM specimens. Hypoxia promotes the expression and secretion of HMGB1 in GSCs. Furthermore, silencing HMGB1 results in the loss of stem cell markers and a reduction in self-renewal ability of GSCs. Additionally, HMGB1 knockdown inhibits the activation of RAGE-dependent ERK1/2 signaling pathway and arrests the cell cycle in GSCs. Consistently, FPS-ZM1, an inhibitor of RAGE, downregulates HMGB1 expression and the phosphorylation of ERK1/2, leading to a reduction in the proliferation of GSCs. In xenograft mice of GBM, HMGB1 knockdown inhibits tumor growth and promotes mouse survival. Collectively, these findings uncover a vital function for HMGB1 in regulating GSC self-renewal potential and tumorigenicity.

Clinical Features of Craniopharyngioma With Tumoral Hemorrhage: A Retrospective Case-Controlled Study.

Background: Craniopharyngioma (CP) with tumoral hemorrhage is a very rare syndrome presenting with various manifestation and unfavorable outcomes. The current retrospective study was performed to summarize the clinical features of CP with tumoral hemorrhage. Methods: In this study, 185 patients with pathological diagnosis of CP (18 patients with hemorrhage) were enrolled. Clinical characteristics, radiological and surgical treatments, and post-operative complications were analyzed. In addition, the correlations between sexual hormones and tumor volume were explored. Results: Drowsiness, acute syndrome, and pituitary deficiency were more frequent in patients with hemorrhage patients. Prothrombin time (PT) were higher in patients with hemorrhage. Luteinizing hormone (LH) and testosterone (T) were lower in male patients with hemorrhage. Post-operative electrolyte disturbances, hypothalamic syndrome, and death appeared more frequently in the hemorrhage group. Moreover, prolactin (PRL) and cortisol 8AM were found to be correlated with the volume of the tumor and the hematoma, respectively. Conclusion: The current study presented the clinical features of CP apoplexy from the aspects of clinical characteristics, radiography, surgical treatment, and post-operative complications. Patients with CP apoplexy could benefit from the proper processing of peritumoral hemorrhage and post-operative monitoring of the electrolyte.

[Corrigendum] LRIG2 promotes the proliferation and cell cycle progression of glioblastoma cells in vitro and in vivo through enhancing PDGFRß signaling.

Subsequently to the publication of the above article and a Corrigendum that addressed the issue of a misspelling of one of the authors' names (DOI: 10.3892/ijo.2019.4769; published online on April 2, 2019), the authors have subsequently discovered that Fig. 7 on p. 1079 contained a duplication in two of the panels that might cause the readers some confusion. The authors were able to re-examine the original data, repeat the experiment, and have decided to revise Fig. 7. The corrected version of Fig. 7, showing replacement data for the p-Akt and Cyclin D1 experiments, is shown on the next page. The authors confirm that these data continue to support the main conclusions presented in their paper, and are grateful to the Editor of International Journal of Oncology for allowing them this opportunity to publish a Corrigendum. They also apologize to the readership for any inconvenience caused. [the original article was published in International Journal of Oncology 10.3892/ijo.2018.4482].

Glioblastoma Immunotherapy Targeting the Innate Immune Checkpoint CD47-SIRPα Axis.

Glioblastoma Multiforme (GBM) is the most common and aggressive form of intracranial tumors with poor prognosis. In recent years, tumor immunotherapy has been an attractive strategy for a variety of tumors. Currently, most immunotherapies take advantage of the adaptive anti-tumor immunity, such as cytotoxic T cells. However, the predominant accumulation of tumor-associated microglia/macrophages (TAMs) results in limited success of these strategies in the glioblastoma. To improve the immunotherapeutic efficacy for GBM, it is detrimental to understand the role of TAM in glioblastoma immunosuppressive microenvironment. In this review, we will discuss the roles of CD47-SIRPα axis in TAMs infiltration and activities and the promising effects of targeting this axis on the activation of both innate and adaptive antitumor immunity in glioblastoma.

Corrigendum: The Prognostic and Therapeutic Potential of LRIG3 and Soluble LRIG3 in Glioblastoma.

[This corrects the article DOI: 10.3389/fonc.2019.00447.].

Prognostic significance of ARL9 and its methylation in low-grade glioma.

This study aimed to determine the value of ARL9 expression or methylation as a biomarker for LGG survival. We investigated the expression, methylation, prognosis and immune significance of ARL9 through bioinformatics analysis. ARL9 is negatively regulated by ARL9 methylation, leading to its low expression in LGG tissues. Both low ARL9 expression and hypermethylation predicted favorable OS and PFS in LGG patients, according to the TCGA database. Cox regression demonstrated that low ARL9 expression and ARL9 hypermethylation were independent biomarkers for OS. Moreover, three other glioma databases were utilized to verify the prognostic role of ARL9 in LGG, and the similar results were reached. A meta-analysis revealed that low ARL9 expression was closely relevant to better OS. Finally, ARL9 expression exhibited a close correlation with some immune cells, especially CD8+ T cells. ARL9 could constitute a promising prognostic biomarker, and probably plays an important role in immune cell infiltration in LGG.

Targeting LRIG2 overcomes resistance to EGFR inhibitor in glioblastoma by modulating GAS6/AXL/SRC signaling.

Epidermal growth factor receptor (EGFR) gene amplification and mutation occurs most frequently in glioblastoma (GBM). However, EGFR-tyrosine kinase inhibitors (TKIs), including gefitinib, have not yet shown clear clinical benefit and the underlying mechanisms remain largely unexplored. We previously demonstrated that LRIG2 plays a protumorigenic role and functions as a modulator of multiple oncogenic receptor tyrosine kinases (RTKs) in GBM. We therefore hypothesized that LRIG2 might mediate the resistance to EGFR inhibitor through modulating other RTK signaling. In this study, we report that LRIG2 is induced by EGFR inhibitor in gefitinib-treated GBM xenografts or cell lines and promotes resistance to EGFR inhibition by driving cell cycle progression and inhibiting apoptosis in GBM cells. Mechanistically, LRIG2 increases the secretion of growth-arrest specific 6 (GAS6) and stabilizes AXL by preventing its proteasome-mediated degradation, leading to enhancement of the gefitinib-induced activation of AXL and then reactivation of the gefitinib-inhibited SRC. Targeting LRIG2 significantly sensitizes the GBM cells to gefitinib, and inhibition of the downstream GAS6/AXL/SRC signaling abrogates LRIG2-mediated gefitinib resistance in vitro and in vivo. Collectively, our findings uncover a novel mechanism in resistance to EGFR inhibition and provide a potential therapeutic strategy to overcome resistance to EGFR inhibition in GBM.

The Prognostic and Therapeutic Potential of LRIG3 and Soluble LRIG3 in Glioblastoma.

Glioblastoma is a highly lethal type of primary brain tumor that exhibits unrestricted growth and aggressive invasion capabilities, leading to a dismal prognosis despite a multitude of therapies. Multiple alterations in the expression level of genes and/or proteins have been identified in glioblastomas, including the activation of oncogenes and/or silencing of tumor-suppressor genes. Nevertheless, there are still no effective targeted therapies associated with these changes. In this study, we investigated the expression of human leucine-rich repeats and immunoglobulin-like domains protein 3 (LRIG3) in human glioma specimens through immunohistochemical analysis. The results showed that LRIG3 was weakly expressed in high-grade gliomas (WHO [World Health Organization] grades III and IV) compared with that in low-grade gliomas (WHO grade II). Survival analysis of these patients with glioma indicated that LRIG3 is an important prognostic marker for better survival. Moreover, we confirmed the existence of soluble ectodomain of LRIG3 (sLRIG3) in the cell culture supernatant, serum, and in tumor cystic fluid of patients with glioma. Molecular mechanistic investigation demonstrated that both LRIG3 and sLRIG3 inhibit the growth and invasion capabilities of GL15, U87, and PriGBM cells and tumor xenografts in nude mice through regulating the MET/phosphatidylinositol 3-kinase/Akt signaling pathway. Enzyme-linked immunosorbent assay confirmed the positive correlation between serum sLRIG3 protein levels and overall survival time in patients with high-grade gliomas. Taken together, our data for the first time demonstrate the existence of sLRIG3 and that both LRIG3 and sLRIG3 are potent tumor suppressors, which could be used as prognostic markers for better overall survival and therapeutic agents for glioblastoma.

[Corrigendum] LRIG2 promotes the proliferation and cell cycle progression of glioblastoma cells in vitro and in vivo through enhancing PDGFRß signaling.

Following the publication of this article, the authors have realized that the name of the second author was misspelt: "Minghai Dong" should have appeared as "Minhai Dong". The correct information for the authors on this paper is presented above. The authors regret that this error made it into print, andapologize to the readership for any inconvenience caused. [the original article was published in International Journal of Oncology 53: 1069­1082, 2018; DOI: 10.3892/ijo.2018.4482].

LRIG2 promotes the proliferation and cell cycle progression of glioblastoma cells in vitro and in vivo through enhancing PDGFRß signaling.

The leucine­rich repeats and immunoglobulin­like domains (LRIG) gene family, comprising LRIG1, 2 and 3, encodes integral membrane proteins. It has been well established that LRIG1 negatively regulates multiple growth factor signaling pathways and is considered to be a tumor suppressor; however, the biological functions of LRIG2 remain largely unexplored. It was previously demonstrated that LRIG2 positively regulates epidermal growth factor receptor (EGFR) signaling, the most common aberrant receptor tyrosine kinase (RTK) signaling in glioblastoma multiforme (GBM), which promotes GBM growth. In the present study, the effect of LRIG2 on the proliferation of GBM cells was further addressed, as well as the possible mechanisms underlying the regulatory effect of LRIG2 on platelet­derived growth factor receptor ß (PDGFRß) signaling, another common oncogenic RTK signaling pathway in GBM. First, the expression levels of endogenous LRIG2 and PDGFRß were found to vary notably in human GBM, and the LRIG2 expression level was positively correlated with the expression level of PDGFRß. Furthermore, to the best of our knowledge, this is the first study to demonstrate that LRIG2 promoted the PDGF­BB­induced proliferation of GBM cells in vitro and in vivo through regulating the PDGFRß signaling­mediated cell cycle progression. Mechanistically, LRIG2 has the ability to physically interact with PDGFRß, promoting the total expression and the activation of PDGFRß, and enhancing its downstream signaling pathways of Akt and signal transducer and activator of transcription 3 and the effectors of key regulators of cell cycle progression, resulting in increased GBM cell proliferation. Collectively, these data indicated that LRIG2 may serve as a tumor promoter gene in gliomagenesis by positively regulating PDGFRß signaling, another important oncogenic RTK signaling pathway, in addition to the previously reported EGFR signaling in GBM modulated by LRIG2, and validated LRIG2 as a promising therapeutic target for the treatment of GBM characterized by multiple aberrant RTK signaling.

LRIG proteins in glioma: Functional roles, molecular mechanisms, and potential clinical implications.

Gliomas are the most common intracranial tumors of the nervous system. These tumors are characterized by unlimited cell proliferation and excessive invasiveness. Despite the advances in diagnostic imaging, microneurosurgical techniques, radiation therapy, and chemotherapy, significant increases in the progression free survival of glioma patients have not been achieved. Improvements in our understanding of the molecular subtypes of gliomas and the underlying alterations in specific signaling pathways may impact both the diagnosis and the treatment strategies for patients with gliomas. Growth factors and their corresponding receptor tyrosine kinases are associated with oncogenesis and development of tumors in numerous human cancer types, including glioma. Leucine-rich repeats and immunoglobulin-like domains (LRIG) are integral membrane proteins which contain three vertebrate members including LRIG1, LRIG2 and LRIG3. They mainly function as regulators of growth factor signaling. Specifically, LRIG1 has been identified as a tumor suppressor in human cancers. In contrast, LRIG2 appears to function as a tumor promoter, while LRIG3 appears to have a function similar to that of LRIG1. In the present review, we summarize the functional roles, molecular mechanisms, and clinical perspectives of LRIG proteins in gliomas and propose that these proteins may be useful in the future as targets for treatment and prognostication in glioma patients.

Downregulation of LRIG2 expression inhibits angiogenesis of glioma via EGFR/VEGF-A pathway.

Active angiogenesis is the basic pathological feature of glioma. Tumor angiogenesis is involved in vascular endothelial cell migration to the tumor tissue and in the formation of tube-like structures. The present study aimed to investigate the role of leucine-rich repeats and immunoglobulin-like domains 2 (LRIG2) in glioma angiogenesis. Glioma (n=50) and normal brain (n=20) tissue samples were collected from patients to detect the expression of LRIG2, epidermal growth factor receptor (EGFR), vascular endothelial growth factor A (VEGF-A), and cluster of differentiation 31 (CD31) using immunohistochemistry. In addition, the association between the expression of LRIG2 in glioma tissue and the microvessel density (MVD) was analyzed. In vitro, the expression of LRIG2 in human glioma U87 and U251 cell lines was knocked down. Subsequently, cell migration and tube formation assays of human umbilical vein endothelial cells (HUVECs) were performed using a coculture system. The protein expression levels of LRIG2, EGFR, phosphorylated-EGFR and VEGF-A were determined using western blotting. The results demonstrated that the expression levels of LRIG2, EGFR, VEGF-A and CD31 were highly upregulated in glioma tissue samples. Furthermore, LRIG2 expression in glioma tissue samples was significantly correlated with the MVD. In vitro, the downregulation of LRIG2 inhibited HUVEC migration and tube formation induced by coculture with glioma cells. The downregulation of LRIG2 resulted in decreased expression of EGFR and VEGF-A. The effects of the LRIG2 knockdown were reversed following EGF treatment. These findings suggest that LRIG2 is a potential target for the inhibition of glioma angiogenesis, which is possibly mediated via the EGFR/VEGF-A signaling pathway.

Comparison of Pituitary Adenomas in Elderly and Younger Adults: Clinical Characteristics, Surgical Outcomes, and Prognosis.

OBJECTIVES: To analyze and summarize the clinical characteristics, surgical outcomes, and prognosis of elderly adults with pituitary adenomas (PAs). DESIGN: Retrospective cohort study. SETTING: Tongji Hospital. PARTICIPANTS: Individuals who underwent transsphenoidal surgery for PAs between 2009 and 2012 (N = 1,104). MEASUREMENTS: Participants were divided into two age groups (≥65 and <65), and their clinical characteristics, surgical complications, surgical outcomes, and follow-up data were analyzed and compared. RESULTS: The older group had longer duration of symptoms. The most common symptom were mass effects (98.4%) in the older group and hormone-secreting effects (55.2%) in the younger group. The incidence of pituitary apoplexy (P = .03), incidentaloma (P = .03) and misdiagnosis at first visit (P < .001) were higher in the older group. Nonfunctioning PAs (P < .001) and giant adenomas (P = .04) were more common in the elderly group than in the younger group. There were no significant differences in the incidence of postoperative diabetes insipidus, cerebrospinal fluid (CSF) leak, regrowth, visual outcome, or permanent hypopituitarism between the groups (P > .05). The incidence of severe systemic complications was greater in the older group (3/69 vs 3/1,035, relative risk = 15.00, 95% confidence interval = 3.08-72.94, P = .004), and all three cases in the older group occurred after emergency surgery. The incidence of hypopituitarism before surgery and 3 days after surgery was higher in the elderly group (P < .05). Older participants tended to have more difficulty recovering from preoperative hypopituitarism (P = .02). CONCLUSION: Avoiding misdiagnosis and emergency surgery is critical for frail elderly adults with multiple comorbidities. With early active management, sufficient preoperative preparation, and multidisciplinary collaboration, the long-term outcomes and prognosis of elderly adults with PAs are comparable with those of younger adults.

Posttraumatic cerebral infarction in severe traumatic brain injury: characteristics, risk factors and potential mechanisms.

BACKGROUND: Posttraumatic cerebral infarction (PTCI) is a severe secondary insult of traumatic brain injury (TBI). This study aimed to evaluate the characteristics and risk factors of PTCI after severe TBI (sTBI) and explore possible mechanism. METHODS: This retrospective study included a cohort of 339 patients with sTBI; they were divided into the PTCI and non-PTCI groups. Clinical data and follow-up charts were reviewed for comparison. The logistic regression model was used for multivariate analysis to detect the risk factors of PTCI. The Glasgow Outcome Scale (GOS) and Barthel index (BI) for activities of daily living (ADL) were applied to evaluate their outcome. RESULTS: PTCI led to an increased mortality (43.5 % vs. 10.7 %, P < 0.001) and days of intensive care unit stay (14.3 days vs. 7.1 days, P < 0.001), decreased GOS (3.1 vs. 4.1, P < 0.001) and BI (25.0 vs. 77.9, P < 0.001). Increased infarction volume led to poor outcome assessed by GOS (r = -0.46, P < 0.0001) and BI for ADL (r = -0.36, P = 0.026) for surviving patients. Compared with non-PTCI patients, PTCI patients had a high incidence of midline shift (36.2 % vs. 20.7 %, P = 0.011) and posttraumatic vasospasm (PTV) (42.0 % vs. 27.4 %, P = 0.027). Daily prevalence of PTCI occurred in two peaks: one (73.9 %) was in the first 24 h after injury, while the other (18.8 %) was in the span of 43 to 60 h postinjury. In multivariate analysis, hyperthermia [adjusted odds ratio (OR), 3.11; P = 0.001] in the first 24 h, thrombocytopenia (OR, 27.08; P < 0.001), abnormal prothrombin time (OR, 7.66; P < 0.001) and traumatic subarachnoid hemorrhage (OR, 2.33; P = 0.022) were independent predictors for PTCI. CONCLUSIONS: PTCI deteriorates the outcome of sTBI patients. Mechanical compression and hemocoagulative disturbance serve as potential mechanisms mediating this pathophysiological process. PTV may also contribute to PTCI, but its association with PTCI is weak and needs further exploration. Early recognition and intervention of these factors might be beneficial for preventing PTCI.

LRIG3 modulates proliferation, apoptosis and invasion of glioblastoma cells as a potent tumor suppressor.

Leucine-rich repeats and immunoglobulin-like domains (LRIG) 3 gene is mapped to chromosome 12q13.2, a region that is frequently deleted in a subset of glioblastoma multiforme (GBM). It has been reported that perinuclear LRIG3 staining correlated with low WHO grade of glioma and better survival of the patients. However, the relationship between LRIG3 and glioma is not very clear. The purpose of this study is to demonstrate the impacts of LRIG3 on biological characteristics of glioma and its possible mechanisms. We found that transduction of LRIG3 into glioblastoma cells inhibited cell growth in vitro and in vivo, promoted cell apoptosis, and restrained cell invasion and migration. Further studies demonstrated that LRIG3 negatively regulated the epidermal growth factor receptor (EGFR) signaling pathway. Inhibition of EGFR could reduce the effects of LRIG3 knockdown on cell proliferation and EGFR signaling pathway. In conclusion, LRIG3 functions as a tumor suppressor by attenuating EGFR signaling pathway and the restoration of LRIG3 may offer therapeutic potential against malignant gliomas.

Hedyotis diffusa Willd extract inhibits the growth of human glioblastoma cells by inducing mitochondrial apoptosis via AKT/ERK pathways.

ETHNOPHARMACOLOGICAL RELEVANCE: Hedyotis diffusa Willd (Rubiaceae) (HDW) has been widely applied for the treatment of tumors, inflammation and toxication in traditional Chinese medicine. The antitumor effect of HDW on glioblastoma has been rarely reported. We aim to evaluate the activity of this extract and explore the underlying mechanism in U87 human glioblastoma cell line. MATERIALS AND METHODS: Cytotoxicity of HDW extract on U87 cells was measured by MTT assay. Apoptosis, cell cycle arrest and mitochondrial membrane potential (MMP) collapse induced by HDW extract were determined by flow cytometry. Caspase activity was analyzed based on colorimetric assay with a microplate spectrophotometer. Protein expression was examined by Western blot. RESULTS: HDW extract suppressed U87 cells growth in a dose- and time-dependent manner. Flow cytometry showed that HDW extract induced significant apoptosis, S/G2-M phase arrest and MMP collapse in U87 cells. Furthermore, dose-dependent activation of caspase-3, Bcl-2, Bax and ERK was observed with HDW extract treatment. Decreased Bcl-2/Bax ratio and Akt suppression were readily found as well. CONCLUSIONS: Induction of mitochondria-mediated apoptosis played an essential role in antitumor activity of HDW extract in U87 cells, in which ERKs and Akt signaling proteins were also involved. These findings contributed to the feasibility of using HDW extract in glioblastoma treatment and the understanding of the molecular mechanism.