Sphere decoding (SD) is an efficient algorithm for Multiple-input Multiple-output (MIMO) digital communications. It has been showed to achieve near Maximum Likelihood (ML) performance with low complexity. However, the complexity of conventional SD algorithm is high under the specific environment. The performance and the computation complexity of SD algorithm is highly dependent on the initial choice of sphere radius. Thus, it is important to design a proper initial radius scheme for SD which improve the performance and reduce the computation complexity. In this paper, we propose a novel scheme base on the knowledge of statistical probability and the constellation energy to design a new initial radius scheme. The performance and algorithmic efficiency of this scheme are increased by application of a factor constellation energy E. The simulation results show under the low signal-to-noise ratio (SNR) condition. The proposed scheme can achieve the aim that save more operation time than the conventional SD algorithm. At the same time, the performance gap compared to conventional SD algorithm can be restricted to a certain level.
Background: Sepsis is an important disease that endangers human health and is the main cause of death in ICU patients, which has been a focus of clinical treatment.This study aims to evaluate the significance of the readily available quick sequential organ failure assessment (qSOFA) score in clinical cases of sepsis.Methods: A retrospective cross-sectional study of patients with sepsis treated in the Department of
Chemoresistance is a major challenge to current ovarian cancer chemotherapy. It is important to identify biomarkers to distinguish chemosensitive and chemoresistant patients. Areas covered: We review the medical literature, discuss MS-based technologies with respect to chemoresistant ovarian cancer and summarize the promising chemoresistant biomarkers identified. In addition, the challenges and future perspectives of biomarker discovery research are explored. With the employment of mass spectrometry-based (MS-based) proteomics, biomarker discovery of ovarian cancer has made great progress in the last decade. Many potential biomarkers were identified by MS-based proteomics technologies, some of which have been validated for further extensive studies in clinical settings. Expert commentary: The discovery of chemoresistant biomarkers is a newly developing area and may provide a clue for predicting chemotherapeutic response and discover therapeutic targets for paving the way of personalized medicine. Multiple complementary MS-based proteomics approaches hold promise for finding novel therapeutic targets in ovarian cancer treatment.
Ovarian cancer is the most common malignant tumor of the female reproductive tract. Chemoresistance is a major challenge for current ovarian cancer therapy. However, the mechanism underlying epithelial ovarian cancer (EOC) chemoresistance is not completely uncovered. The phosphatidylinositol-3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling is an important intracellular pathway in regulating cell cycle, quiescence, and proliferation. The aim of this study is to investigate the role of PI3K/Akt/mTOR signaling pathway and its association with epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC) marker expression in EOC chemoresistance.The expressions of EMT and CSC markers were detected by immunofluorescence, western blot, and quantitative real-time PCR. BEZ235, a dual PI3K/mTOR inhibitor, was employed to investigate the role of PI3K/Akt/ mTOR signaling in regulating EMT and CSC marker expression. Students' t test and one-way ANOVA with Tukey's post-hoc test were used to compare the data from different groups.We found that EMT and CSC marker expression were significantly enhanced in chemoresistant EOC cells, which was accompanied by the activation of PI3K/Akt/mTOR signaling. Compared with single cisplatin treatment, combined treatment with BEZ235 and cisplatin significantly disrupted the colony formation ability, induced higher ROS level and more apoptosis in chemoresistant EOC cells. Furthermore, the combination approach effectively inhibited PI3K/Akt/mTOR signaling pathway, reversed EMT, and decreased CSC marker expression in chemoresistant EOC cells compared with cisplatin mono-treatment.Our results first demonstrate that EMT and enhanced CSC marker expression triggered by activated PI3K/Akt/mTOR signaling are involved in the chemoresistance of EOC, and BEZ235 in combination with cisplatin might be a promising treatment option to reverse EOC chemoresistance.
Radioresistance is a major challenge for prostate cancer (CaP) metastasis and recurrence after radiotherapy. This study aimed to identify potential protein markers and signaling pathways associated with radioresistance using a PC-3 radioresistant (RR) subcutaneous xenograft mouse model and verify the radiosensitization effect from a selected potential candidate. PC-3RR and PC-3 xenograft tumors were established and differential protein expression profiles from two groups of xenografts were analyzed using liquid chromatography tandem-mass spectrometry. One selected glycolysis marker, lactate dehydrogenase A (LDHA) was validated, and further investigated for its role in CaP radioresistance. We found that 378 proteins and 51 pathways were significantly differentially expressed between PC-3RR and PC-3 xenograft tumors, and that the glycolysis pathway is closely linked with CaP radioresistance. In addition, we also demonstrated that knock down of LDHA with siRNA or inhibition of LDHA activity with a LDHA specific inhibitor (FX-11), could sensitize PC-3RR cells to radiotherapy with reduced epithelial-mesenchymal transition, hypoxia, DNA repair ability and autophagy, as well as increased DNA double strand breaks and apoptosis. In summary, we identified a list of potential RR protein markers and important signaling pathways from a PC-3RR xenograft mouse model, and demonstrate that targeting LDHA combined with radiotherapy could increase radiosensitivity in RR CaP cells, suggesting that LDHA is an ideal therapeutic target to develop combination therapy for overcoming CaP radioresistance.
Abstract Background: Chemotherapy is the mainstay treatment for ovarian cancer (OC). Chemoresistance is a major challenge in epithelial ovarian cancer (EOC) therapy. CHTOP was identified as a potential chemoresistant biomarker in chemoresistant EOC cell lines using label-free LC-MS/MS proteomic technique. However, the role of CHTOP in EOC chemoresistance is still unclear. Aim: In this study, we aimed to investigate whether CHTOP can be used as a therapeutic target in chemoresistant EOC cells and to reveal the mechanism underlying chemosensitization. Methods: The expression difference of CHTOP was detected in chemoresistant and metastatic EOC cell lines by immunofluorescence (IF) and Western blot (WB). The expression of CHTOP in human EOC tissues was examined using immunohistochemistry (IHC). The effect of CHTOP knockdown (KD) on metastasis was examined using the Transwell® matrigel invasion and wound healing assays. Flow cytometry and TUNEL assay were employed to determine the association of CHTOP with apoptosis, while mammary sphere formation assay and IF were used to evaluate its regulation on EOC-cis cell stemness. Results: The higher expression of CHTOP was found in EOC-cis (A2780-cis and IGROV-1-cis) and metastatic EOC (SKOV-3 and OV-90) cells as compared to normal epithelial ovarian cells (HOSE) by IF and WB. Also, high expression of CHTOP was found in human EOC tissues and associated with poor prognosis in patients. In contrast, CHTOP KD significantly reduced the metastatic potential of EOC-cis cells and increased their apoptosis at the presence of cisplatin. Furthermore, CHTOP KD decreased the stemness of EOC-cis cells. Conclusion: Our findings suggest that CHTOP is associated with metastasis, apoptosis, and stemness in chemoresistant EOC cells, the survival in EOC patients, and might be a promising therapeutic target to overcome chemoresistance in EOC treatment. Keywords: ovarian cancer, chemoresistance, CHTOP, metastasis, apoptosis, stemness Citation Format: Xupeng Bai, Xiaojie Feng, Jie Ni, Julia Beretov, Junli Deng, Ying Zhu, Peter Graham, Yong Li. CHTOP is a novel therapeutic target for chemoresistant epithelial ovarian cancer therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4754.
// Junli Deng 1,2,3,4 , Li Wang 3,4 , Hongmin Chen 3,4 , Jingli Hao 1,2 , Jie Ni 1,2 , Lei Chang 1,2 , Wei Duan 5 , Peter Graham 1,2 and Yong Li 1,2 1 Cancer Care Centre, St George Hospital, Kogarah, NSW, Australia 2 St George and Sutherland Clinical School, University of New South Wales (UNSW), Kensington, NSW, Australia 3 Department of Gynecological Oncology, Henan Cancer Hospital, Zhengzhou, Henan, China 4 Zhengzhou University, Zhengzhou, Henan, China 5 School of Medicine, Deakin University, Waurn Ponds, Victoria, Australia Correspondence to: Yong Li, email: // Keywords : ovarian cancer, EMT, CSC, chemoresistance, therapy Received : February 11, 2016 Accepted : May 30, 2016 Published : June 09, 2016 Abstract Chemoresistance is the main challenge for the recurrent ovarian cancer therapy and responsible for treatment failure and unfavorable clinical outcome. Understanding mechanisms of chemoresistance in ovarian cancer would help to predict disease progression, develop new therapies and personalize systemic therapy. In the last decade, accumulating evidence demonstrates that epithelial-mesenchymal transition and cancer stem cells play important roles in ovarian cancer chemoresistance and metastasis. Treatment of epithelial-mesenchymal transition and cancer stem cells holds promise for improving current ovarian cancer therapies and prolonging the survival of recurrent ovarian cancer patients in the future. In this review, we focus on the role of epithelial-mesenchymal transition and cancer stem cells in ovarian cancer chemoresistance and explore the therapeutic implications for developing epithelial-mesenchymal transition and cancer stem cells associated therapies for future ovarian cancer treatment.
Abstract Aims: Prostate cancer (CaP) is the most common cancer in males in Australia which caused more than 3000 deaths in 2015. EpCAM is a transmembrane protein that is expressed at low levels in a variety of human epithelial tissues, but overexpressed in most solid tumors. Our previous study indicated that EpCAM was strongly expressed in metastatic CaP cell lines, primary human CaP tissues and lymph node metastasis and is a biomarker involved in CaP progression, and chemo-/radio-resistance. However, the role of EpCAM in CaP progression and therapeutic resistance is still uncertain. The aim of this study was to investigate the role of EpCAM in CaP progression and chemo-/radio-resistance as well as underlying mechanisms in vitro and in vivo. Methods: EpCAM gene was knocked down (KD) in PC-3, DU145 and LNCaP CaP cell lines using shRNA. Proliferation assay, colony formation assay, docetaxel (DTX) and radiation dose-response assay were carried out to evaluate the effect of KD of EpCAM on proliferation and therapeutic response of CaP cells in vitro. Subcutaneous (s.c) and orthotopic CaP animal models were established using PC-3-EpCAM-KD and PC-3-EpCAM-scramble (scr) control cells in NOD/SCID mice, to assess the effect of EpCAM on CaP tumourigenecity, chemotherapy (DTX) and radiation response. Signal transduction proteins in PI3K/Akt/mTOR signaling pathway, as well as proliferation, apoptotic and radiation response markers were evaluated by immunohistochemistry in xenografts. Results: KD of EpCAM reduced CaP proliferative potential and enhanced DTX and radiation sensitivity in three CaP cell lines. Both s.c and orthotopic EpCAM-KD xenografts displayed suppressed tumor growth and increased DTX and radiation responsiveness compared to EpCAM-scr control xenografts in NOD/SCID mice. Marked down-regulation of PI3K/Akt/mTOR pathway proteins (p-Akt and p-mTOR) and proliferation marker (Ki-67) and significant up-regulation of apoptotic (Caspase-3) and radiation (γ-H2AX) responses to chemo-/radio-therapies were found in EpCAM-KD xenografts, compared with control xenografts. In addition, Kaplan-Meier curve analysis demonstrated that KD of EpCAM improved median survival (MS) of tumor-bearing mice by 21.5 days compared with the control group (HR=26.94, CI95% 4.317-168.1, p=0.0004) and that KD of EpCAM improved MS of tumor-bearing mice which received docetaxel (50mg/kg, single dose, i.p.) by 11 days (HR=20.95, CI95% 3.599-121.9, p=0.0007), and radiotherapy (2Gy/day for 4 days) by 12 days (HR=11.00, CI95% 2.11-57.36, p=0.0044) compared with the control group, respectively. Conclusions: EpCAM plays an important role in CaP progression and chemo-/radio-resistance via PI3K/Akt/mTOR signaling pathway in vitro and in vivo and it is a promising therapeutic target for the treatment of CaP. EpCAM targeted therapy combined with chemo-/radio-therapy could be a novel modality for treatment-resistant CaP. Citation Format: Jie Ni, Paul Cozzi, Julia Beretov, Junli Deng, Joseph Bucci, Peter Graham, Yong Li. Epithelial cell adhesion molecule (EpCAM) is associated with prostate cancer progression and chemo-/radio-resistance in vitro and in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2833. doi:10.1158/1538-7445.AM2017-2833