Research on natural products from traditional Chinese medicine in the treatment of myocardial ischemia-reperfusion injury

Myocardial ischemia-reperfusion injury (MIRI) is a complicated pathologic process that involves multiple factors including oxidative stress (free radical damage), inflammatory response, calcium overloading, and apoptosis in cardiomyocytes. According to Traditional Chinese Medicine (TCM), MIRI belongs to the categories of "chest numbness", "palpitations" and "angina pectoris". Present data indicate that the application of TCM in myocardial ischemia-reperfusion injury is promising and continues to attract research attention. While the efficacy of Chinese herbal medicine has been well-proven, the underlying molecular mechanisms remain elusive. The common proven mechanisms of Chinese herbal medicine in the treatment of MIRI include regulating lipid metabolism, protecting mitochondria, and improving energy metabolism, attenuating calcium (Ca²⁺) overload, scavenging oxygen free radicals, inhibiting apoptosis, and reducing autophagy. Others are the regulation of inflammatory cytokine expressions and healing of inflammatory lesions, modulation of cell signaling pathways, improvement of endothelial cell function, and protection of myocardial cells. In this review, we highlight recent studies that focus on elucidating these molecular mechanisms and the therapeutic effects of natural compounds deriving from TCM in MIRI, to ascertain the research progress made and the prospects in this field.

The Dose-Response Associations of Sedentary Time with Chronic Diseases and the Risk for All-Cause Mortality Affected by Different Health Status: A Systematic Review and Meta-Analysis

PURPOSE

To determine the dose-response associations of sedentary behaviour with cardiovascular diseases (CVD), cancer, and all-cause mortality, and to examine whether the sedentary-associated all-cause mortality risk was affected by appearance of diabetes and hypertension, physical activity, and body mass index (BMI).

DESIGN

We carried out a systematic review and meta-analysis to search Medline, SportDiscus, and Web of Science for eligible studies.

SETTINGS

Prospective cohort studies that reported sedentary time and CVD, cancer, and mortality incidents.

MEASUREMENTS

Two authors independently extracted data based on predefined criteria. The effect estimates were evaluated by hazard ratios (HRs) with 95% confidences (CIs).

RESULTS

Twenty-four studies met the inclusion criteria. Sitting time showed dose-response associations with CVD, cancer, and all-cause mortality, with each 1-hour increment of sitting time daily accounting for HRs 1.04 (95% CIs 1.02-1.07), 1.01 (1.00-1.02), and 1.03 (1.02-1.03), respectively. The link between sitting time and CVD and all-cause mortality was non-linear (pnon-linear < 0.0001). The relationship between TV viewing and CVD and all-cause mortality was dose-dependent, with HRs 1.07 (1.06-1.09) and 1.04 (1.01-1.06) for per 1-hour increment of TV time every day, respectively. The regression was curved (pnon-linear < 0.0001). When the analysis was stratified by the percentage of diabetes and hypertension, BMI values, and physical activity levels, we found that higher BMI and a greater percentage of diabetes and hypertension further increased all-cause mortality risk in the most sedentary populations, whereas higher physical activity levels decreased it.

CONCLUSION

Sitting time and TV viewing significantly increased cardiovascular, cancer, and mortality risk; the associations were dose-dependent. More importantly, sedentary behaviour in combination with chronic diseases or high BMI increased all-cause mortality risk whereas physical activity was likely to alleviate the adverse associations.

Higher-Order Quantum Ghost Imaging with Ultracold Atoms

Ghost imaging is a quantum optics technique that uses correlations between two beams to reconstruct an image from photons that do not interact with the object being imaged. While pairwise (second-order) correlations are usually used to create the ghost image, higher-order correlations can be utilized to improve the performance. In this Letter, we demonstrate higher-order atomic ghost imaging, using entangled ultracold metastable helium atoms from an s-wave collision halo. We construct higher-order ghost images up to fifth order and show that using higher-order correlations can improve the visibility of the images without impacting the resolution. This is the first demonstration of higher-order ghost imaging with massive particles and the first higher-order ghost imaging protocol of any type using a quantum source.

Abstract P5-07-04: Transition from a pre-malignant lesion to cancer does not require stemness of the cancer-originating cells in the lesion

The precancerous lesion is the final step before malignancy, and is thus a key step to cancer prevention. Precancerous lesions are heterogeneous harboring distinct subsets of cells from stem cells to differentiated cells. Whether the stem cells or other subsets in these precancerous lesions are responsible for the eventual cancer remains unanswered. Here, we report that in the precancerous lesions of the MMTV-Wnt1 model of basal-like breast cancer, there exist the stem cell-enriched keratin 6a+ subset and more differentiated WAP+ cell subset. We demonstrate that both mutated Ras and B-Raf can robustly transform both cell subsets into cancer. These data suggest that multiple cell subsets in precancerous early lesions can evolve into cancer. This finding indicates that cancer prevention should target both self-renewing cells and other cell subsets in developing precancerous lesions in high-risk individuals.

Citation Format: Bu W, Li Y. Transition from a pre-malignant lesion to cancer does not require stemness of the cancer-originating cells in the lesion [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-07-04.

Abstract P2-07-08: Neuroleptics in breast cancer risk

This abstract was not presented at the symposium.

Abstract P2-06-11: Wild type N-Ras, overexpressed in basal-like breast cancer, promotes tumor formation by inducing IL8 secretion via JAK2 activation

"Basal-like" breast cancer (BLBC) is a very aggressive subtype of breast cancer. BLBC has very poor prognosis — median time to distant recurrence is just 2.6 years vs. 5 years overall, and survival time from diagnosis of distant metastatic disease is 9 months vs. 22 months. BLBC tumors usually do not express ER, Her2, or progesterone receptor. As such, they cannot be treated by the current targeted therapies, which target these molecules. What drive the formation and progression of BLBCs is largely unclear.

Ras GTPases are best known for mediating growth factor signaling. Oncogenic mutations in the RAS genes, K-RAS in particular, are found in more than 30% of human tumors. Surprisingly, oncogenic RAS mutations are rare in breast cancer. However, we found that wild-type N-RAS is overexpressed in BLBCs, possibly partly via promoter demethylation, but not in other breast cancer subtypes. Repressing N-RAS inhibits transformation and tumor growth, while overexpressing it enhances these processes even in preinvasive BLBC cells. In contrast, in breast cancer cells of other subtypes, repressing N-RAS expression does not affect growth and transforming activities. We identified N-Ras-responsive genes, most of which encode chemokines and cytokines, e.g., IL8. High expression levels of these N-Ras-responsive genes as well as of N-RAS itself in tumors correlate with poor patient outcome. N-Ras, but not K-Ras, induces IL8 by binding and activating the cytoplasmic pool of JAK2; IL8 then acts on both the cancer cells and stromal fibroblasts.

In conclusion, N-Ras drives BLBC by promoting transformation in epithelial cells, which may in turn remodel the tumor microenvironment to create a proinvasive state. Although oncogenic mutations affecting RAS are common in many other human cancers, tumorigenesis in an important subset of breast cancers is driven instead by increasing activity of wild-type N-Ras. Thus, to fully assess the impact of Ras on tumorigenesis, the role of wild-type as well as mutant Ras proteins must be carefully examined.

Citation Format: Zheng Z-Y, Bu W, Tian L, Fan C, Gao X, Zhang X, Yu C, Wang H, Liao Y-H, Li Y, Lewis MT, Edwards D, Zwaka TP, Hilsenbeck SG, Medina D, Perou CM, Creighton CJ, Zhang XH, Chang EC. Wild type N-Ras, overexpressed in basal-like breast cancer, promotes tumor formation by inducing IL8 secretion via JAK2 activation. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-06-11.

Luminal epithelial cells within the mammary gland can produce basal cells upon oncogenic stress

In the normal mammary gland, the basal epithelium is known to be bipotent and can generate either basal or luminal cells, whereas the luminal epithelium has not been demonstrated to contribute to the basal compartment in an intact and normally developed mammary gland. It is not clear whether cellular heterogeneity within a breast tumor results from transformation of bipotent basal cells or from transformation and subsequent basal conversion of the more differentiated luminal cells. Here we used a retroviral vector to express an oncogene specifically in a small number of the mammary luminal epithelial cells and tested their potential to produce basal cells during tumorigenesis. This in-vivo lineage-tracing work demonstrates that luminal cells are capable of producing basal cells on activation of either polyoma middle T antigen or ErbB2 signaling. These findings reveal the plasticity of the luminal compartment during tumorigenesis and provide an explanation for cellular heterogeneity within a cancer.

Functionalized upconversion nanoparticles: versatile nanoplatforms for translational research

The design, application, and translation of targeted multimodality molecular imaging probes based on nanotechnology have attracted increasing attentions during the last decade and will continue to play vital roles in cancer diagnosis and personalized medicine. With the growing awareness of drawbacks of traditional organic dyes and quantum dots, biocompatible lanthanide ion doped upconversion nanoparticles have emerged as promising candidates for clinically translatable imaging probes, owing to their unique features that are suitable for future targeted multimodal imaging in living subjects. In this review, we summarized the recent advances in the field of functionalized upconversion nanoparticles (f-UCNP) for biological imaging and therapy in vivo, and discussed the future research directions, obstacles ahead, and the potential use of f-UCNP in translational research.

Microstructure Formation in Extruded and Drawn Polyblends of PC with a Thermotropic LCP

Melt blending, extrusion and drawing of polycarbonate (PC) blends containing a thermotropic liquid crystalline polymer (LCP) are reported for a copolyester PCDT synthesised in this laboratory. A single screw extruder is used at four temperatures. The rheology of the PCDT/PC blend, PCDT and PC was measured by means of a capillary rheometer at these temperatures. The morphology of extruded and subsequently drawn strands was studied with the help of a scanning electron microscope and analysed. In PCDT/PC extruded strands, the morphology of the PCDT dispersed phase, changes from spherical through ellipsoidal to elongated with decreasing processing temperature. In contrast to this, in drawn strands with a draw ratio of 10, the morphology of the PCDT changes from ellipsoidal through elongated to fibrillar with increasing processing temperature. It is believed that the relative viscosity of the two phases is the decisive factor determining the microstructure formation of polymer blends containing thermotropic liquid crystalline polymers. Fibril formation is related to the deformation and coalescence of PCDT melt droplets by the drawing at higher temperatures.

mDia1 and WAVE2 proteins interact directly with IRSp53 in filopodia and are involved in filopodium formation

Filopodia are dynamic actin-rich cell surface protrusions involved in cell migration, axon guidance, and wound healing. The RhoGTPase Cdc42 generates filopodia via IRSp53, a multidomain protein that links the processes of plasma membrane deformation and actin dynamics required for their formation in mammalian cells. The Src homology 3 domain of IRSp53 binds to the actin regulators Mena, Eps8, WAVE1, WAVE2, mDia1, and mDia2. We show that mDia1 and WAVE2 synergize with IRSp53 to form filopodia. IRSp53 also interacts directly with these two proteins within filopodia, as observed in acceptor photobleaching FRET studies. Measurement of filopodium formation by time-lapse imaging of live cells also revealed that depleting neuronal cells of either mDia1 or WAVE2 protein decreases the ability of IRSp53 to induce filopodia. In contrast, IRSp53 does not appear to partner WAVE1 or mDia2 to give rise to these structures. In addition, although all three isoforms of mDia are capable of inducing filopodia, IRSp53 requires only mDia1 to do so. These findings suggest that mDia1 and WAVE2 are important Src homology 3 domain partners of IRSp53 in forming filopodia.

F-BAR domain proteins: Families and function

The F-BAR domain is emerging as an important player in membrane remodeling pathways. F-BAR domain proteins couple membrane remodeling with actin dynamics associated with endocytic pathways and filopodium formation. Here, we provide a comprehensive analysis of F-BAR domain proteins in terms of their evolutionary relationships and protein function. F-BAR domain containing proteins can be categorized into five subfamilies based on their phylogeny which is consistent with the additional protein domains they possess, for example, RhoGAP domains, Cdc42 binding sites, SH3 domains and tyrosine kinase domains. We derive a protein-protein interaction network suggesting that dynamin1/2, N-WASP, Huntingtin, intersectin and Cdc42 are central nodes influencing F-BAR domain protein function.

Cdc42 interaction with N-WASP and Toca-1 regulates membrane tubulation, vesicle formation and vesicle motility: implications for endocytosis

Transducer of Cdc42-dependent actin assembly (Toca-1) consists of an F-BAR domain, a Cdc42 binding site and an SH3 domain. Toca-1 interacts with N-WASP, an activator of actin nucleation that binds Cdc42. Cdc42 may play an important role in regulating Toca-1 and N-WASP functions. We report here that the cellular expression of Toca-1 and N-WASP induces membrane tubulation and the formation of motile vesicles. Marker and uptake analysis suggests that the tubules and vesicles are associated with clathrin-mediated endocytosis. Forster resonance energy transfer (FRET) and Fluorescence Lifetime Imaging Microscopy (FLIM) analysis shows that Cdc42, N-WASP and Toca-1 form a trimer complex on the membrane tubules and vesicles and that Cdc42 interaction with N-WASP is critical for complex formation. Modulation of Cdc42 interaction with Toca-1 and/or N-WASP affects membrane tubulation, vesicle formation and vesicle motility. Thus Cdc42 may influence endocytic membrane trafficking by regulating the formation and activity of the Toca-1/N-WASP complex.

Evolving generalized Voronoi diagrams for accurate cellular image segmentation

Analyzing cellular morphologies on a cell-by-cell basis is vital for drug discovery, cell biology, and many other biological studies. Interactions between cells in their culture environments cause cells to touch each other in acquired microscopy images. Because of this phenomenon, cell segmentation is a challenging task, especially when the cells are of similar brightness and of highly variable shapes. The concept of topological dependence and the maximum common boundary (MCB) algorithm are presented in our previous work (Yu et al., Cytometry Part A 2009;75A:289-297). However, the MCB algorithm suffers a few shortcomings, such as low computational efficiency and difficulties in generalizing to higher dimensions. To overcome these limitations, we present the evolving generalized Voronoi diagram (EGVD) algorithm. Utilizing image intensity and geometric information, EGVD preserves topological dependence easily in both 2D and 3D images, such that touching cells can be segmented satisfactorily. A systematic comparison with other methods demonstrates that EGVD is accurate and much more efficient.

I-BAR domains, IRSp53 and filopodium formation

Filopodia and lamellipodia are dynamic actin-based structures that determine cell shape and migration. Filopodia are thought to sense the environment and direct processes such as axon guidance and neurite outgrowth. Cdc42 is a small GTP-binding protein and member of the RhoGTPase family. Cdc42 and its effector IRSp53 (insulin receptor phosphotyrosine 53 kDa substrate) have been shown to be strong inducers of filopodium formation. IRSp53 consists of an I-BAR (inverse-Bin-Amphiphysin-Rvs) domain, a Cdc42-binding domain and an SH3 domain. The I-BAR domain of IRSp53 induces membrane tubulation of vesicles and dynamic membrane protrusions lacking actin in cells. The IRSp53 SH3 domain interacts with proteins that regulate actin filament formation e.g. Mena, N-WASP, mDia1 and Eps8. In this review we suggest that the mechanism for Cdc42-driven filopodium formation involves coupling I-BAR domain-induced membrane protrusion with SH3 domain-mediated actin dynamics through IRSp53.

Quantitative neurite outgrowth measurement based on image segmentation with topological dependence

The study of neuronal morphology and neurite outgrowth has been enhanced by the combination of imaging informatics and high content screening, in which thousands of images are acquired using robotic fluorescent microscopy. To understand the process of neurite outgrowth in the context of neuroregeneration, we used mouse neuroblastoma N1E115 as our model neuronal cell. Six-thousand cellular images of four different culture conditions were acquired with two-channel widefield fluorescent microscopy. We developed a software package called NeuronCyto. It is a fully automatic solution for neurite length measurement and complexity analysis. A novel approach based on topological analysis is presented to segment cells. The detected nuclei were used as references to initialize the level set function. Merging and splitting of cells segments were prevented using dynamic watershed lines based on the constraint of topological dependence. A tracing algorithm was developed to automatically trace neurites and measure their lengths quantitatively on a cell-by-cell basis. NeuronCyto analyzes three important biologically relevant features, which are the length, branching complexity, and number of neurites. The application of NeuronCyto on the experiments of Toca-1 and serum starvation show that the transfection of Toca-1 cDNA induces longer neurites with more complexities than serum starvation.

Determination of in vivo dissociation constant, KD, of Cdc42-effector complexes in live mammalian cells using single wavelength fluorescence cross-correlation spectroscopy

The RhoGTPase Cdc42 coordinates cell morphogenesis, cell cycle, and cell polarity decisions downstream of membrane-bound receptors through distinct effector pathways. Cdc42-effector protein interactions represent important elements of cell signaling pathways that regulate cell biology in systems as diverse as yeast and humans. To derive mechanistic insights into cell signaling pathways, it is vital that we generate quantitative data from in vivo systems. We need to be able to measure parameters such as protein concentrations, rates of diffusion, and dissociation constants (K(D)) of protein-protein interactions in vivo. Here we show how single wavelength fluorescence cross-correlation spectroscopy in combination with Förster resonance energy transfer analysis can be used to determine K(D) of Cdc42-effector interactions in live mammalian cells. Constructs encoding green fluorescent protein or monomeric red fluorescent protein fusion proteins of Cdc42, an effector domain (CRIB), and two effectors, neural Wiskott-Aldrich syndrome protein (N-WASP) and insulin receptor substrate protein (IRSp53), were expressed as pairs in Chinese hamster ovary cells, and concentrations of free protein as well as complexed protein were determined. The measured K(D) for Cdc42V12-N-WASP, Cdc42V12-CRIB, and Cdc42V12-IRSp53 was 27, 250, and 391 nm, respectively. The determination of K(D) for Cdc42-effector interactions opens the way to describe cell signaling pathways quantitatively in vivo in mammalian cells.

The Toca-1-N-WASP complex links filopodial formation to endocytosis

The transducer of Cdc42-dependent actin assembly (Toca-1)-N-WASP complex was isolated as an essential cofactor for Cdc42-driven actin polymerization in vitro. Toca-1 consists of an N-terminal F-BAR domain, followed by a Cdc42 binding site (HR1 domain) and an SH3 domain, (the N-WASP interacting site). N-WASP is an activator of actin nucleation through the Arp2/3 complex. The aim of the present study was to investigate the cellular function of the Toca-1-N-WASP complex. We report that Toca-1 induces filopodia and neurites as does N-WASP in N1E115 neuroblastoma cells. Toca-1 requires the F-BAR domain, Cdc42 binding site, and SH3 domain to induce filopodia. Toca-1 and N-WASP both require each other to induce filopodia. The expression of Toca-1 and N-WASP affects the distribution, size, and number of Rab5 positive membranes. Toca-1 interacts directly with N-WASP in filopodia and Rab5 membrane as seen by Forster resonance energy transfer. Thus the Toca-1-N-WASP complex localizes to and induces the formation of filopodia and endocytic vesicles. Last, three inhibitors of endocytosis, Dynamin-K44A, Eps15Delta95/295, and clathrin heavy chain RNA interference, block Toca-1-induced filopodial formation. Taken together, these data suggest that the Toca-1-N-WASP complex can link filopodial formation to endocytosis.

The Cdc42 effector IRSp53 generates filopodia by coupling membrane protrusion with actin dynamics

The Cdc42 effector IRSp53 is a strong inducer of filopodia formation and consists of an Src homology domain 3 (SH3), a potential WW-binding motif, a partial-Cdc42/Rac interacting binding region motif, and an Inverse-Bin-Amphiphysins-Rvs (I-BAR) domain. We show that IRSp53 interacts directly with neuronal Wiskott-Aldrich syndrome protein (N-WASP) via its SH3 domain and furthermore that N-WASP is required for filopodia formation as IRSp53 failed to induce filopodia formation in N-WASP knock-out (KO) fibroblasts. IRSp53-induced filopodia formation can be reconstituted in N-WASP KO fibroblasts by full-length N-WASP, by N-WASPDeltaWA (a mutant unable to activate the Arp2/3 complex), and by N-WASPH208D (a mutant unable to bind Cdc42). IRSp53 failed to induce filopodia in mammalian enabled (Mena)/VASP KO cells, and N-WASP failed to induce filopodia when IRSp53 was knocked down with RNA interference. The IRSp53 I-BAR domain alone induces dynamic membrane protrusions that lack actin and are smaller than normal filopodia ("partial-filopodia") in both wild-type N-WASP and N-WASP KO cells. We propose that IRSp53 generates filopodia by coupling membrane protrusion through its I-BAR domain with actin dynamics through SH3 domain binding partners, including N-WASP and Mena.

Charge inversion at minute electrolyte concentrations

Anionic dimyristoylphosphatidic acid monolayers spread on LaCl3 solutions reveal strong cation adsorption and a sharp transition to surface overcharging at unexpectedly low bulk salt concentrations. We determine the surface accumulation of La3+ with anomalous x-ray reflectivity and find that La3+ compensates the lipid surface charge by forming a Stern layer with approximately 1 La3+ ion per 3 lipids below a critical bulk concentration, ct approximately 500 nM. Above ct, the surface concentration of La3+ increases to a saturation level with approximately 1 La3+ per lipid, thus implying that the total electric charge of the La3+ exceeds the surface charge. This overcharge is observed at approximately 4 orders of magnitude lower concentration than predicted in ion-ion correlation theories. We suggest that transverse electrostatic correlations between mobile ions and surface charges (interfacial Bjerrum pairing) may contribute to the charge inversion.

Regulation of microtubule assembly by human EB1 family proteins

The EB1 family proteins are highly conserved microtubule-associated proteins. The EB1 protein in yeast has been shown to play an important role in regulating microtubule dynamics and chromosome segregation. Human EB1 family proteins include EB1, RP1 and EBF3. Although EB1 and RP1 have been shown to associate with microtubules, the subcellular localization of endogenous EBF3 had not been characterized. The function of human EB1 family proteins was also not clear. We therefore investigated the cellular localization of EBF3 and the regulation of microtubule organization by EB1 family proteins. As do EB1 and RP1, EBF3 was found to colocalize with microtubules, preferentially at their plus ends, throughout the cell cycle. Moreover, there was a very strong EBF3 signal at the centrosome in interphase cells and at the spindle poles in mitotic cells. When EB1 family proteins were overexpressed, they associated with the entire microtubule cytoskeleton. In addition, EB1 and EBF3 induced microtubule bundling in some cells overexpressing these proteins. These microtubule bundles were more resistant to nocodazole and were more acetylated than regular microtubules. Our results demonstrate for the first time that human EB1 family proteins could regulate microtubule assembly and stability.

[Cloning, sequence analysis and high-level expression in Escherichia coli and activity assay of pac-1 gene from Schizosaccharmyces pombe]

The Schizosaccharmyces pombe pac-1 gene product is a kind of dsRNA dependent ribonuclease, which has potential to degrade the dsRNA viral genome, the replication form of ssRNA viral genome and viroid genome. Therefore, to introduce the pac-1 gene into plants conferring them resistance to viruses is a new method of establishing the anti-virus transgenic plant. The pac-1 gene from the S. pmobe genome DNA isolated from China was cloned by means of PCR amplification. The pac-1 gene was inserted into the cloning vector pGEM-7Zf(+) by using restriction endonuclease Kpn I/BamHI. Sequencing analysis shows that it is a complete gene with 1095 necleotides. Compared to the reported pac-1 gene, its homology is significant, but with 5 nucleotides differences, leading to only one amino acid difference. Pac-1 gene was inserted into the prodaryotic expression vector pET-21(a) by using the restriction endonuclase Nde I/BamHI. It was induced by the IPTG in E. coli BL21 harbouring the recombinant vector pET-pac-1. The pac-1 gene product is analyzed by the SDS-PAGE. The result shows the product of pac-1 gene exists in the supernatant part as soluble form and in the precipitant part as inclusion bodies after the cells were lysed by ultrasonic wave. The supernatant was applied to detect the enzyme activity of pac-1 gene product. We concluded that pac-1 gene has the biological activity of degrading the CMV-dsRNA.

Effect of antiangiogenic agents on experimental animal models of hepatocellular carcinoma

A new therapeutic strategy for treating metastasis in hepatocellular carcinoma (HCC) has entailed the use of antiangiogenic agents such as suramin, BB-94 (Batimastat), TNP-470, and carboxyamido-triazole (CAI, a synthetic inhibitor of non-excitable calcium channels that reversibly inhibits angiogenesis). These agents have been used to treat metastatic model of HCC in nude mouse (LCI-D20 mouse model). The results of these studies are summarized in this paper with emphasis on the inhibitory effects of the drugs on tumour growth, angiogenesis, invasion and metastasis in LCI-D20 mouse models. The results suggest that all of the agents used can significantly inhibit tumour growth, angiogenesis, invasion and metastasis of human HCC in nude mouse models, and may be candidates for the control of recurrence and metastasis after HCC resection.

Effects of matrix metalloproteinase inhibitor BB-94 on liver cancer growth and metastasis in a patient-like orthotopic model LCI-D20

BACKGROUND/AIMS

The aim of this study was to try to understand the effects of the synthetic matrix metalloproteinase inhibitor Batimastat (BB-94) on hepatocellular carcinoma (HCC).

METHODOLOGY

An orthotopic metastatic human hepatocellular carcinoma in nude mice model (LCI-D20) was used to study primary tumor growth, local invasion and metastasis of HCC. MTT assay was used to study the effects of BB-94 on cytotoxin and proliferation of HCC cell line SMMC-7721 in vitro. A gelatine zymograph was used to study the expression of MMPs in the LCI-D20 tumor tissue.

RESULTS

BB-94 can inhibit primary tumor growth, local invasion, intrahepatic and lung metastasis, as well as prolong survival. BB-94 did not affect the proliferation of HCC cells in vitro. LCI-D20 tumor tissue expresses MMP-2 and MMP-9.

CONCLUSIONS

BB-94 has a cytostatic therapeutic effect on HCC.

[The role of MMP-2 in the invasion and metastasis of hepatocellular carcinoma (HCC)]

OBJECTIVES

To get insights into the role of MMP-2 in the invasion and metastasis of hepatocellular carcinoma (HCC), and to find a method to judge the invasion and metastasis of HCC through MMP-2.

METHODS

Zymograph and immunohistochemistry were used to study the content and types of positive cells of MMP-2 in the HCC, and statistical methods were used to analyse the association between the content of MMP-2 and the pathological indexes of HCC.

RESULTS

MMP-2 was expressed by all the normal liver, HCC and surrounding liver parenchyma. The increase of MMP-2 and the presence of the active type of MMP-2 were related to the invasion and metastasis of HCC. The content of MMP-2 in HCC being higher than that in surrounding liver parenchyma was an important index to judge the invasion and metastasis of the HCC. The positive cells of MMP-2 found in immunohistochemistry were normal hepatocytes, cholangioepithelial cells, Ito cells, regenerated hepatocytes, new generated cholangioepithelial cells, and HCC cells.

CONCLUSION

MMP-2 was related to the invasion and me astasis of HCC. The content of MMP-2 in HCC being higher than that in surrounding liver parenchyma could be bused as an important index to judge the invasion and metastasis of HCC.

Metabolic factors capable of inducing Agrobacterium vir gene expression are present in rice (Oryza sativa L.)

The effects of exudates and extracts from suspension cultures or various parts of rice (Oryza sativa L.) plants on induction of vir (virulence) gene expression in Agrobacterium tumefaciens were examined. Only leaf extracts from panicle-differentiating plants to flowering plants were able to strongly induce activation and expression of vir genes. This induction was similar to that observed with 2 μM acetosyringone (AS), yet there was no synergy between AS and rice extracts. Responses to vir-inducing metabolites and signal molecules were different among various vir loci. These results demonstrate that one or more inducing factors for vir gene expression are also present in rice, but only in specific parts and developmental stages.