Development of a Serum-Based MicroRNA Signature for Early Detection of Pancreatic Cancer: A Multicenter Cohort Study.

BACKGROUND: A grim prognosis of pancreatic cancer (PCa) was attributed to the difficulty in early diagnosis of the disease. AIMS: Identifying novel biomarkers for early detection of PCa is thus urgent to improve the overall survival rates of patients. METHODS: The study was performed firstly by identification of candidate microRNAs (miRNAs) in formalin-fixed, paraffin-embedded tissues using microarray profiles, and followed by validation in a serum-based cohort study to assess clinical utility of the candidates. In the cohorts, a total of 1273 participants from four centers were retrospectively recruited as two cohorts including training and validation cohort. The collected serum specimens were analyzed by real-time polymerase chain reaction. RESULTS: We identified 27 miRNAs expressed differentially in PCa tissues as compared to the benign. Of which, the top-four was selected as a panel whose diagnostic efficacy was fully assessed in the serum specimens. The panel exhibited superior to CA19-9, CA125, CEA and CA242 in discriminating patients with early stage PCa from healthy controls or non-PCa including chronic pancreatitis as well as pancreatic cystic neoplasms, with the area under the curves (AUC) of 0.971 (95% CI 0.956-0.987) and 0.924 (95% CI 0.899-0.949), respectively. Moreover, the panel eliminated interference from other digestive tumors with a specificity of 90.2%. CONCLUSIONS: A panel of four serum miRNAs was developed showing remarkably discriminative ability of early stage PCa from either healthy controls or other pancreatic diseases, suggesting it may be developed as a novel, noninvasive approach for early screening of PCa in clinic.

Noncancerous disease-targeting AIEgens.

Noncancerous diseases include a wide plethora of medical conditions beyond cancer and are a major cause of mortality around the world. Despite progresses in clinical research, many puzzles about these diseases remain unanswered, and new therapies are continuously being sought. The evolution of bio-nanomedicine has enabled huge advancements in biosensing, diagnosis, bioimaging, and therapeutics. The recent development of aggregation-induced emission luminogens (AIEgens) has provided an impetus to the field of molecular bionanomaterials. Following aggregation, AIEgens show strong emission, overcoming the problems associated with the aggregation-caused quenching (ACQ) effect. They also have other unique properties, including low background interferences, high signal-to-noise ratios, photostability, and excellent biocompatibility, along with activatable aggregation-enhanced theranostic effects, which help them achieve excellent therapeutic effects as an one-for-all multimodal theranostic platform. This review provides a comprehensive overview of the overall progresses in AIEgen-based nanoplatforms for the detection, diagnosis, bioimaging, and bioimaging-guided treatment of noncancerous diseases. In addition, it details future perspectives and the potential clinical applications of these AIEgens in noncancerous diseases are also proposed. This review hopes to motivate further interest in this topic and promote ideation for the further exploration of more advanced AIEgens in a broad range of biomedical and clinical applications in patients with noncancerous diseases.

Pancreatitis initiated pancreatic ductal adenocarcinoma: Pathophysiology explaining clinical evidence.

Pancreatic ductal adenocarcinoma (PDAC) is a highly malignant lethal disease due to its asymptomatic at its early lesion of the disease and drug resistance. Target therapy associated with molecular pathways so far seems not to produce reasonable outcomes. Understanding of the molecular mechanisms underlying inflammation-initiated tumorigenesis may be helpful for development of an effective therapy of the disease. A line of studies showed that pancreatic tumorigenesis was resulted from pancreatitis, which was caused synergistically by various pancreatic cells. This review focuses on those players and their possible clinic implications, such as exocrine acinar cells, ductal cells, and various stromal cells, including pancreatic stellate cells (PSCs), macrophages, lymphocytes, neutrophils, mast cells, adipocytes and endothelial cells, working together with each other in an inflammation-mediated microenvironment governed by a myriad of cellular signaling networks towards PDAC.

Tracer-Based Cancer Metabolomic Analysis.

Metabolic rewiring/reprogramming is an essential hallmark of cancer. Alteration of metabolic phenotypes is occurred in cancer cells in response to a harsh condition to support cancer cell proliferation, survival, and metastasis. Stable isotope can be used as a tracer to investigate the redistribution of the carbons labeled in glucose in order to elucidate the detailed mechanisms of cellular rewiring and reprogramming in tumor microenvironment. Stable isotope-resolved metabolomics (SIRM) is an analytical method inferring metabolic networking by using advanced nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS) to analyze the fate of a single atom from a stable isotope-enriched precursor to a product metabolite. This methodology has been demonstrated for a wide range of biological applications, including cancer metabolomic analysis. The basic principle and platforms of SIRM and its implication for cancer metabolism research will be addressed in this chapter.

Progress on the role of reactive oxygen species-mediated tumor microenvironment in pancreatic cancer.

Pancreatic cancer (PC) is a devastating malignant tumor with high incidence and mortality rate worldwide. Meanwhile, the surgical approaches and drugs of this disease remain challenging. In recent years, reactive oxygen species (ROSs) study has become a hotspot in the field of PC research. ROSs may regulate tumor mic roenvironment (TME), cancer stem cells (CSCs) renewal and epithelial-mesenchymal transition (EMT), which result in drug-resistance and recurrence of the PC. Currently, TME that includes immune infiltrates, fibroblasts, vascular vessels and extracellular matrix has become a hotspot in the cancer research. Meanwhile, numerous researches have shown that ROSs-mediated TME plays a central role in the occurrence and development of PC. Targeting ROSs may be promising therapeutic treatments for the PC patients. Therefore, the purposes of the review were manifold: (1) to summarize the regulations of ROSs in tumorigenesis and drug-resistance of PC; (2) to investigate the modulation of ROSs in signaling cascades in PC; (3) to study the effects of ROSs in stromal cells in PC; (4) to generalize the potent therapies targeting ROSs in PC. Overall, this review summarized the current status of ROSs in PC research and suggested some potential anti-PC drugs that may target ROSs.

Loss of Setd2 promotes Kras-induced acinar-to-ductal metaplasia and epithelia-mesenchymal transition during pancreatic carcinogenesis.

OBJECTIVE: SETD2, the sole histone H3K36 trimethyltransferase, is frequently mutated or deleted in human cancer, including pancreatic ductal adenocarcinoma (PDAC). However, whether SETD2/H3K36me3 alteration results in PDAC remains largely unknown. DESIGN: TCGA(PAAD) public database and PDAC tissue array with SETD2/H3K36me3 staining were used to investigate the clinical relevance of SETD2 in PDAC. Furthermore, to define the role of SETD2 in the carcinogenesis of PDAC, we crossed conditional Setd2 knockout mice (PdxcreSetd2flox/flox) together with KrasG12D mice. Moreover, to examine the role of SETD2 after ductal metaplasia, Crisp/cas9 was used to deplete Setd2 in PDAC cells. RNA-seq and H3K36me3 ChIP-seq were performed to uncover the mechanism. RESULTS: SETD2 mutant/low expression was correlated with poor prognosis in patients with PDAC. Next, we found that Setd2 acted as a putative tumour suppressor in Kras-driven pancreatic carcinogenesis. Mechanistically, Setd2 loss in acinar cells facilitated Kras-induced acinar-to-ductal reprogramming, mainly through epigenetic dysregulation of Fbxw7. Moreover, Setd2 ablation in pancreatic cancer cells enhanced epithelia-mesenchymal transition (EMT) through impaired epigenetic regulation of Ctnna1. In addition, Setd2 deficiency led to sustained Akt activation via inherent extracellular matrix (ECM) production, which would favour their metastasis. CONCLUSION: Together, our findings highlight the function of SETD2 during pancreatic carcinogenesis, which would advance our understanding of epigenetic dysregulation in PDAC. Moreover, it may also pave the way for development of targeted, patients-tailored therapies for PDAC patients with SETD2 deficiency.

Research progress on long non-coding RNAs and their roles as potential biomarkers for diagnosis and prognosis in pancreatic cancer.

Pancreatic cancer is one of the main causes of tumor-related deaths worldwide because of its low morbidity but extremely high mortality, and is therefore colloquially known as the "king of cancer." Sudden onset and lack of early diagnostic biomarkers directly contribute to the extremely high mortality rate of pancreatic cancer patients, and also make it indistinguishable from benign pancreatic diseases and precancerous pancreatic lesions. Additionally, the lack of effective prognostic biomarkers makes it difficult for clinicians to formulate precise follow-up strategies based on the postoperative characteristics of the patients, which results in missed early diagnosis of recurrent pancreatic cancer. Long non-coding RNAs (lncRNAs) can influence cell proliferation, invasion/migration, apoptosis, and even chemoresistance via regulation of various signaling pathways, leading to pro- or anti-cancer outcomes. Given the versatile effects of lncRNAs on tumor progression, using a single lncRNA or combination of several lncRNAs may be an effective method for tumor diagnosis and prognostic predictions. This review will give a comprehensive overview of the most recent research related to lncRNAs in pancreatic cancer progression, as targeted therapies, and as biomarkers for the diagnosis and prognosis of pancreatic cancer.

MicroRNAs as effective surrogate biomarkers for early diagnosis of oral cancer.

BACKGROUND: Oral squamous cell carcinomas (OC) are life-threatening diseases emerging as major international health concerns. OBJECTIVE: Development of an efficient clinical strategy for early diagnosis of the disease is a key for reducing the death rate. Biomarkers are proven to be an effective approach for clinical diagnosis of cancer. Although mechanisms underlying regulation of oral malignancy are still unclear, microRNAs (miRNAs) as a group of small non-coded RNAs may be developed as the effective biomarkers used for early detection of oral cancer. METHODS: A literature search was conducted using the databases of PubMed, Web of Science, and the Cochrane Library. The following search terms were used: miRNAs and oral cancer or oral carcinoma. A critical appraisal of the included studies was performed with upregulated miRNAs and downregulated miRNAs in oral cancer. RESULTS: In this review, we summarize the research progress made in miRNAs for diagnosis of oral cancer. The involvement of miRNAs identified in signal transduction pathways in OC, including Ras/MAPK signaling, PI3K/AKT signaling, JAK/STAT signaling, Wnt/ß-catenin signaling, Notch signaling, and TGF-ß/SMAD signaling pathway. CONCLUSIONS: A number of studies demonstrated that miRNAs may be developed as an ideal set of biomarkers used for early diagnosis and prognosis of cancers because of the stability in human peripheral blood and body fluids and availability of non-invasive approaches being developed for clinical utility. CLINICAL RELEVANCE: These findings suggest that miRNAs as biomarkers may be useful for diagnosis of OC.

Metabolic Regulation in Mitochondria and Drug Resistance.

Mitochondria are generally considered as a powerhouse in a cell where the majority of the cellular ATP and metabolite productions occur. Metabolic rewiring and reprogramming may be initiated and regulated by mitochondrial enzymes. The hypothesis that cellular metabolic rewiring and reprogramming processes may occur as cellular microenvironment is disturbed, resulting in alteration of cell phenotype, such as cancer cells resistant to therapeutics seems to be now acceptable. Cancer metabolic reprogramming regulated by mitochondrial enzymes is now one of the hallmarks of cancer. This chapter provides an overview of cancer metabolism and summarizes progress made in mitochondria-mediated metabolic regulation in cancer drug resistance.

Treatment with Rhizoma Dioscoreae extract has protective effect on osteopenia in ovariectomized rats.

The aims of this study were to evaluate the osteoprotective effect of aqueous extract from Rhizoma Dioscoreae (RDE) on rats with ovariectomy- (OVX-) induced osteopenia. Our results show that RDE could inhibit bone loss of OVX rats after a 12-week treatment. The microarray analysis showed that 68 genes were upregulated and that 100 genes were downregulated in femurs of the RDE group rats compared to those in the OVX group. The Ingenuity Pathway Analysis (IPA) showed that several downregulated genes had the potential to code for proteins that were involved in the Wnt/ ß -catenin signaling pathway (Sost, Lrp6, Tcf7l2, and Alpl) and the RANKL/RANK signaling pathway (Map2k6 and Nfatc4). These results revealed that the mechanism for an antiosteopenic effect of RDE might lie in the synchronous inhibitory effects on both the bone formation and the bone resorption, which is associated with modulating the Wnt/ ß -catenin signaling and the RANKL/RANK signaling.

High-dose diosgenin reduces bone loss in ovariectomized rats via attenuation of the RANKL/OPG ratio.

The aim of this study was to evaluate effect of diosgenin (DG) on rats that had osteoporosis-like features induced by ovariectomy (OVX). Seventy-two six-month-old female Wistar rats were subjected to either ovariectomy (n = 60) or Sham operation (SHAM group, n = 12). Beginning at one week post-ovariectomy, the OVX rats were treated with vehicle (OVX group, n = 12), estradiol valerate (EV group, n = 12), or DG at three doses (DG-L, -M, -H group, n = 12, respectively). After a 12-week treatment, administration of EV or DG-H inhibited OVX-induced weight gain, and administration of EV or DG-H or DG-M had a significantly uterotrophic effect. Bone mineral density (BMD) and indices of bone histomorphometry of tibia were measured. Levels of protein and mRNA expression of osteoprotegerin (OPG) and receptor activator of nuclear factor kappa-B ligand (RANKL) in tibia were evaluated by immunohistochemistry and in situ hybridization. Our results show that DG at a high dose (DG-H) had a significant anti-osteoporotic effect compared to OVX control. DG-H treatment down-regulated expression of RANKL and up-regulated expression of OPG significantly in tibia from OVX rats compared to control, and thus lowered the RANKL/OPG ratio. This suggests that the anti-osteoporotic effect of DG might be associated with modulating the RANKL/OPG ratio and DG had potential to be developed as alternative therapeutic agents of osteoporosis induced by postmenopause.

Obg-like ATPase 1 exacerbated gemcitabine drug resistance of pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is a highly malignant disease with a poor prognosis due to inefficient diagnosis and tenacious drug resistance. Obg-like ATPase 1 (OLA1) is overexpressed in many malignant tumors. The molecular mechanism of OLA1 underlying gemcitabine (GEM)-induced drug resistance was investigated in this study. An enhanced expression of OLA1 was observed in a GEM acquired resistant pancreatic cancer cell lines and in patients with pancreatic cancer. Overexpressed OLA1 showed poor overall survival rates in patients with pancreatic cancer. Dysregulation of the OLA1 reduced expression of CD44+/CD133+, and improved the sensitivity of pancreatic cancer cells to GEM. OLA1 highly expression facilitated the formation of the OLA1/Sonic Hedgehog (SHH)/Hedgehog-interacting protein (HHIP) complex in nuclei, resulting in the inhibition of negative feedback of Hedgehog signaling induced by HHIP. This study suggests that OLA1 may be developed as an innovative drug target for an effective therapy of pancreatic cancer.

Semen Astragali Complanati- and Rhizoma Cibotii-enhanced bone formation in osteoporosis rats.

BACKGROUND: Growing evidence shows that herb medicines have some anti-osteoporotic effects, the mechanism underlying is unknown. This study aims to investigate the therapeutic effect of Chinese herb supplements on rats that had osteoporosis-like symptom induced by ovariectomy (OVX). METHODS: OVX or sham operations were performed on virgin Wistar rats at three-month old, which were randomly divided into eight groups: sham (sham); OVX control group (OVX); OVX rats with treatments [either diethylstilbestrol (DES) or Semen Astragali Complanati decoction (SACD) or Rhizoma Cibotii decoction (RCD) or Herba Cistanches decoction (HCD) or Semen Allii Tuberosi decoction (SATD)]. Non-surgical rats were served as a normal control (NC). The treatments began 4 weeks after surgery, and lasted for 12 weeks. Bone mass and its turnover were analyzed by histomorphometry. Levels of protein and mRNA of osteoprotegerin (OPG) and receptor activator of nuclear factor κB ligand (RANKL) in osteoblasts (OB) and bone marrow stromal cells (bMSC) were evaluated by immunohistochemistry and in situ hybridization. RESULTS: Compared to OVX control, TBV% in both SACD and RCD groups was increased significantly, while TRS%, TFS%, MAR, and mAR were decreased remarkably in the SACD group, only TRS% decreased dramatically in the RCD group. No significant changes in bone formation were observed in either HCD or SATD groups. OPG levels in both protein and mRNA were reduced consistantly in OB and bMSC from OVX control rats, in contrast, RANKL levels in both protein and mRNA were increased significantly. These effects were substantially reversed by treatments with either DES or SACD or RCD. No significant changes in both OPG and RANKL expression were observed in OB and bMSC from OVX rats treated with SATD and HCD. CONCLUSIONS: Our study showed that SACD and RCD increased bone formation by stimulating OPG expression and downregulating RANKL expression in OB and bMSC. This suggests that SACD and RCD may be developed as alternative anti-osteoporotic agents for therapy of postmenopausal osteoporosis.

Characterization of human colorectal cancer MDR1/P-gp Fab antibody.

In this study, the peptide sized 21 kDa covering P-gp transmembrane region was first prepared for generating a novel mouse monoclonal antibody Fab fragment with biological activity against multiple drug resistance protein P-gp21 by phage display technology. Phage-displayed antibody library prepared from mice spleen tissues was selected against the recombinant protein P-gp21 with five rounds of panning. A number of clones expressing Fab bound to P-gp21, showing neutralized activity in vitro, were isolated and screened by enzyme-linked immunosorbent assay based on its recognition properties to P-gp21 and human colorectal cancer tissue homogenate, resulting in identification of an optimal recombinant Fab clone (Number 29). Further characterization by recloning number 29 into an expression vector showed significant induction of the Fab antibody in the clone number 29 by Isopropyl ß-D-1-thiogalactopyranoside (IPTG). After purified by HiTrap Protein L, the specificity of the Fab antibody to P-gp21 was also confirmed. Not only was the targeted region of this monoclonal Fab antibody identified as a 16-peptide epitope (ALKDKKELEGSGKIAT) comprising residues 883-898 within the transmembrane (TM) domain of human P-gp, but also the binding ability with it was verified. The clinical implication of our results for development of personalized therapy of colorectal cancer will be further studied.

Multifunctional Calcium-Manganese Nanomodulator Provides Antitumor Treatment and Improved Immunotherapy via Reprogramming of the Tumor Microenvironment.

Ions play a vital role in regulating various biological processes, including metabolic and immune homeostasis, which involves tumorigenesis and therapy. Thus, the perturbation of ion homeostasis can induce tumor cell death and evoke immune responses, providing specific antitumor effects. However, antitumor strategies that exploit the effects of multiion perturbation are rare. We herein prepared a pH-responsive nanomodulator by coloading curcumin (CU, a Ca2+ enhancer) with CaCO3 and MnO2 into nanoparticles coated with a cancer cell membrane. This nanoplatform was aimed at reprogramming the tumor microenvironment (TME) and providing an antitumor treatment through ion fluctuation. The obtained nanoplatform, called CM NPs, could neutralize protons by decomposing CaCO3 and attenuating cellular acidity, they could generate Ca2+ and release CU, elevating Ca2+ levels and promoting ROS generation in the mitochondria and endoplasmic reticulum, thus, inducing immunogenic cell death. Mn2+ could decompose the endogenous H2O2 into O2 to relieve hypoxia and enhance the sensitivity of cGAS, activating the cGAS-STING signaling pathway. In addition, this strategy allowed the reprogramming of the immune TME, inducing macrophage polarization and dendritic cell maturation via antigen cross-presentation, thereby increasing the immune system's ability to combat the tumor effectively. Moreover, the as-prepared nanoparticles enhanced the antitumor responses of the αPD1 treatment. This study proposes an effective strategy to combat tumors via the reprogramming of the tumor TME and the alteration of essential ions concentrations. Thus, it shows great potential for future clinical applications as a complementary approach along with other multimodal treatment strategies.

Macrophages in immunoregulation and therapeutics.

Macrophages exist in various tissues, several body cavities, and around mucosal surfaces and are a vital part of the innate immune system for host defense against many pathogens and cancers. Macrophages possess binary M1/M2 macrophage polarization settings, which perform a central role in an array of immune tasks via intrinsic signal cascades and, therefore, must be precisely regulated. Many crucial questions about macrophage signaling and immune modulation are yet to be uncovered. In addition, the clinical importance of tumor-associated macrophages is becoming more widely recognized as significant progress has been made in understanding their biology. Moreover, they are an integral part of the tumor microenvironment, playing a part in the regulation of a wide variety of processes including angiogenesis, extracellular matrix transformation, cancer cell proliferation, metastasis, immunosuppression, and resistance to chemotherapeutic and checkpoint blockade immunotherapies. Herein, we discuss immune regulation in macrophage polarization and signaling, mechanical stresses and modulation, metabolic signaling pathways, mitochondrial and transcriptional, and epigenetic regulation. Furthermore, we have broadly extended the understanding of macrophages in extracellular traps and the essential roles of autophagy and aging in regulating macrophage functions. Moreover, we discussed recent advances in macrophages-mediated immune regulation of autoimmune diseases and tumorigenesis. Lastly, we discussed targeted macrophage therapy to portray prospective targets for therapeutic strategies in health and diseases.

Coadaptation fostered by the SLIT2-ROBO1 axis facilitates liver metastasis of pancreatic ductal adenocarcinoma.

To explore the mechanism of coadaptation and the potential drivers of pancreatic ductal adenocarcinoma (PDAC) metastasis to the liver, we study key molecules involved in this process and their translational value. Premetastatic niche (PMN) and macrometastatic niche (MMN) formation in a mouse model is observed via CT combined with 3D organ reconstruction bioluminescence imaging, and then we screen slit guidance ligand 2 (SLIT2) and its receptor roundabout guidance receptor 1 (ROBO1) as important factors. After we confirm the expression and distribution of SLIT2 and ROBO1 in samples from PDAC patients and several mouse models, we discover that SLIT2-ROBO1-mediated coadaptation facilitated the implantation and outgrowth of PDAC disseminated tumour cells (DTCs) in the liver. We also demonstrate the dependence receptor (DR) characteristics of ROBO1 in a follow-up mechanistic study. A neutralizing antibody targeting ROBO1 significantly attenuate liver metastasis of PDAC by preventing the coadaptation effect. Thus, we demonstrate that coadaptation is supported by the DR characteristics in the PMN and MMN.

Smoke-induced signal molecules in bone marrow cells from altered low-density lipoprotein receptor-related protein 5 mice.

Mechanism underlying smoke-induced loss of bone mass is unknown. In this study, we hypothesized that protein signals induced by smoking in bone marrow may be associated with the loss of bone mass. Using a proteomics approach, we identified 38 proteins differentially expressed in bone marrow cells from low-density lipoprotein receptor-related protein 5 (Lrp5) mice exposed to cigarette smoking. Smoking effects on protein expression in bone marrow among three genotypes (Lrp5(+/+), Lrp5(G171V), and Lrp5(-/-)) varied. On the basis of the ratio of protein expression induced by smoking versus nonsmoking, smoke induced protein expression significantly in wild-type mice compared to the other two genotypes (Lrp5(G171V) and Lrp5(-/-)). These proteins include inhibitors of ß-catenin and proteins associated with differentiation of osteoclasts. We observed that S100A8 and S100A9 were overexpressed in human smokers compared to nonsmokers, which confirmed the effect of smoking on the expression of two proteins in Lrp5 mice, suggesting the role of these proteins in bone remodeling. Smoke induced expression of S100A8 and S100A9 in a time-dependent fashion, which was opposite of the changes in the ratio of OPG/RANKL in bone marrow cells, suggesting that the high levels of S100A8 and S100A9 may be associated with smoke-induced bone loss by increasing bone resorption.

Regulation of breast cancer tumorigenesis and metastasis by miRNAs.

miRNAs are a family of 17- to 23-nucleotide noncoding small RNAs that primarily function as gene expression fine regulators. A number of studies have shown that miRNAs play an important role in breast tumorigenesis, metastasis, proliferation and differentiation of breast cancer stem cells. This short review summarizes the progression of miRNA-mediated breast tumorigenesis and metastasis through various signaling pathways associated with drug resistance.

Therapeutic effects of radix dipsaci, pyrola herb, and Cynomorium songaricum on bone metabolism of ovariectomized rats.

BACKGROUND: The objective of this study was to evaluate the effects of herbal medicines, such as Radix Dipsaci (RDD), Pyrola Herb (PHD), and Cynomorium songaricum decoction (CSD), on osteoporotic rats induced by ovariectomy (OVX). METHODS: OVX or sham operations were performed on 69 virgin Wistar rats that were divided into six groups: sham (sham, n = 12), OVX control group (OVX, n = 12), and OVX rats with treatments (diethylstilbestrol, E2, n = 12; RDD, n = 11, PHD, n = 11, and CSD, n = 11). Non-surgical rats served as normal control (NC, n = 12). The treatments began four weeks after surgery and lasted for 12 weeks. Bone mass and bone turnover were analyzed by histomorphometry. Levels of protein expression and mRNA of OPG and RANKL in osteoblasts (OB) and bone marrow stromal cells (bMSC) were evaluated by immunohistochemistry and in situ hybridization. RESULTS: Compared to NC and sham rats, trabecular bone formation was significantly reduced in OVX rats, but restored in E2-treated rats. Treatment with either RDD or PHD enhanced trabecular bone formation remarkably. No significant change of bone formation was observed in CSD-treated rats. OPG expression of protein and mRNA was reduced significantly in OB and bMSC of OVX control rats. RANKL expression of protein and mRNA was increased significantly in OB and bMSC of OVX control rats. These effects were substantially reversed (increased in OPG and decreased in RANKL) by treatment with E2, RDD, or PHD in OB and bMSC of OVX rats. No significant changes in either OPG or RANKL expression were observed in OB and bMSC of OVX rats treated with CSD. CONCLUSIONS: Our study showed that RDD and PHD increased bone formation by stimulating overexpression of OPG and downregulation of RANKL in OB and bMSC. This suggests that RDD and PHD may be used as alternative therapeutic agents for postmenopausal osteoporosis.