JAG1 promotes migration, invasion, and adhesion of triple-negative breast cancer cells by promoting angiogenesis / 南方医科大学学报

OBJECTIVE@#To investigate the effect of JAG1 on the malignant phenotype of triple-negative breast cancer (TNBC) and its role in angiogenesis in breast cancer microenvironment.@*METHODS@#The expressions of Notch molecules were detected in human TNBC 231 and 231B cells using RT-qPCR. Five female nude mice were inoculated with 231 cells and another 5 with 231B cells into the mammary fat pads, and 4-6 weeks later, the tumors were collected for immunohistochemical and immunofluorescence tests. 231 cells and 231B cells were treated with recombinant JAG (rJAG) protein and DAPT, respectively, and changes in their malignant phenotypes were assessed using CCK-8 assay, Hoechst 33258 staining, wound healing assay, Transwell chamber assay and endothelial cell adhesion assay. Western blotting was used to detect the changes in the expressions of proteins related with the malignant phenotypes of 231 and 231B cells. The effects of conditioned medium (CM) derived from untreated 231 and 231 B cells, rJAG1-treated 231 cells and DAPT-treated 231B cells on proliferation and tube formation ability of cultured human umbilical vein endothelial cells (HUVECs) were evaluated using CCK-8 assay and tube-forming assay.@*RESULTS@#The expression of JAG1 was higher in 231B cells than in 231 cells (P < 0.05). Tumor 231B showed higher expression of VEGFA and CD31. Compared with 231-Blank group, the migration, invasion and adhesion of 231 cells in 231-rJAG1 were significantly enhanced (P < 0.05). Protein levels of Twist1 and Snail increased (P < 0.01), anti-apoptotic protein Bcl-2 increased (P < 0.05), while DAPT inhibited the related phenomena and indicators of 231B. The 231-rJAG1-CM increased the cell number and tubule number of HUVEC (P < 0.05).@*CONCLUSION@#JAG1 may affect the malignant phenotype of TNBC and promote angiogenesis in the tumor microenvironment.

TGF-beta receptor mediated telomerase inhibition, telomere shortening and breast cancer cell senescence

Human telomerase reverse transcriptase (hTERT) plays a central role in telomere lengthening for continuous cell proliferation, but it remains unclear how extracellular cues regulate telomerase lengthening of telomeres. Here we report that the cytokine bone morphogenetic protein-7 (BMP7) induces the hTERT gene repression in a BMPRII receptor- and Smad3-dependent manner in human breast cancer cells. Chonic exposure of human breast cancer cells to BMP7 results in short telomeres, cell senescence and apoptosis. Mutation of the BMPRII receptor, but not TGFbRII, ACTRIIA or ACTRIIB receptor, inhibits BMP7-induced repression of the hTERT gene promoter activity, leading to increased telomerase activity, lengthened telomeres and continued cell proliferation. Expression of hTERT prevents BMP7-induced breast cancer cell senescence and apoptosis. Thus, our data suggest that BMP7 induces breast cancer cell aging by a mechanism involving BMPRII receptor- and Smad3-mediated repression of the hTERT gene.

Current aging research in China

The mini-review stemmed from a recent meeting on national aging research strategies in China discusses the components and challenges of aging research in China. Highlighted are the major efforts of a number of research teams, funding situations and outstanding examples of recent major research achievements. Finally, authors discuss potential targets and strategies of aging research in China.

Molecular dynamics and principal components of potassium binding with human telomeric intra-molecular G-quadruplex

Telomere assumes intra-molecular G-quadruplex that is a significant drug target for inhibiting telomerase maintenance of telomeres in cancer. Metal cations have been recognized as playing important roles in stabilizing G-quadruplex, but their binding processes to human telomeric G-quadruplex remain uncharacterized. To investigate the detailed binding procedures, molecular dynamics simulations were conducted on the hybrid [3 + 1] form-one human telomeric intra-molecular G-quadruplex. We show here that the binding of a potassium ion to a G-tetrad core is mediated by two alternative pathways. Principal component analysis illustrated the dominant concerted motions of G-quadruplex occurred at the loop domains. MM-PBSA calculations revealed that binding was energetically favorable and driven by the electrostatic interactions. The lower binding site was found more constructive favorable for binding. Our data provide useful information on a potassium-mediated stable structure of human telomeric intra-molecular G-quadruplex, implicating in ion disorder associated conformational changes and targeted drug design.

Clinical features of antiviral therapy-induced thyroid disease in patients with chronic hepatitis C / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the clinical features of thyroid disease occurring in response to antiviral therapy in patients with chronic hepatitis C (CHC).</p><p><b>METHODS</b>Eighty-two patients diagnosed with CHC were recruited for study from our hospital between 2009 and 2010. All patients were given a 48-week course of antiviral combination therapy with pegylated-interferon (Peg-IFN; 180 mug qw ih) and ribavirin (RBV; 15 mg/kg bw). Patient sera was collected prior to treatment (baseline), at treatment weeks 24 and 48, and post-treatment week 24, and used to detect changes in levels of thyroid function markers, thyroid-specific and other autoantibodies, complement factors, and immunoglobulins (Igs). Differential expression of biomarkers was assessed between patients who developed thyroid disorder and those who did not.</p><p><b>RESULTS</b>At treatment week 48, 13.4% (11/82) of cases developed hypothyroidism, 3.7% (3/82) developed hyperthyroidism, 20.7% (17/82) tested positive for thyroglobulin antibody, and 22.0% (18/82) tested positive for thyroid peroxidase antibody. The patients who did not develop thyroid disease had significantly higher post-treatment levels (vs. baseline) of IgG (14.84 +/- 2.61 vs. 12.95 +/- 3.32 g/L, F = 10.458, P = 0.002) and C4 (0.26 +/- 0.09 vs. 0.22 +/- 0.08 g/L, F = 6.835, P = 0.011) and significantly lower IgM (0.86 +/- 0.48 vs. 1.00 +/- 0.42 g/L, F = 9.106, P = 0.003). The patients who developed thyroid disease showed no significant differences in the baseline and post-treatment levels of IgG, C4, or IgM. When the two groups of patients who did or did not develop thyroid disease were compared, there was no difference in the amount of patients who achieved sustained virological response.</p><p><b>CONCLUSION</b>Antiviral-induced thyroid disease in patients with refractory hepatitis C manifests as clinically-detectable abnormalities in serum levels of thyroid autoantibody and markers of hypothyroidism. Levels of other autoantibodies and Igs do not correlate with the development of thyroid disease in these patients, and thyroid disease does not appear to affect the efficacy of Peg-IFN + RBV antiviral therapy.</p>

Efficacy of standard antiviral therapy retreatment following interferon treatment failure in chronic hepatitis C patients / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the therapeutic efficacy of standard antiviral therapy applied after interferon (IFN) treatment failure in patients with chronic hepatitis C (CHC).</p><p><b>METHODS</b>CHC patients who completed a 48-week course of IFN therapy (pegylated (Peg)-IFNa-2a at 180 mug, qw, ih with or without ribavirin (RBV) at 15 mg/kg/w) in our hospital between January 2009 and June 2012 but who showed no response (at week 48) or who relapsed (at week 72) were enrolled in the study. Prior to initiating the 48-week course of retreatment therapy (Peg-IFNa-2a plus RBV as above), the hepatitis C virus (HCV) genotype was detected and the viral load measured (baseline) by PCR of HCV RNA. Each patient's response to therapy was classified as follows: baseline vs. week 4 (rapid virological response, RVR), vs. weeks 12 and 24 (early virological response, EVR), vs. week 48 (end of treatment virological response, ETVR) and vs. week 72 (sustained virological response, SVR).</p><p><b>RESULTS</b>Of the total 235 cases administered retreatment therapy, 60.0% (n = 140) achieved RVR, 77.4% (n = 182) achieved EVR, 83.8% (n = 197) achieved ETVR, 68.0% (n = 68%) achieved SVR, and 15.7% (n = 37) relapsed. Stratification analysis of recurrence (n = 158) and non-responsive (n = 77) sub-groups showed that the recurrence group experienced significantly higher rates of RVR, EVR, ETVR and SVR, but a significantly lower rate of relapse. Stratification analysis of genotype 1b carrier (n = 206) and non-1b carrier (n = 29) sub-groups showed that the 1b carriers had significantly lower rates of RVR, EVR, ETVR and SVR, but a significantly higher rate of relapse. Finally, the patients who achieved RVR (vs. non RVR, n = 95) and EVR (vs. non-EVR, n = 53) showed higher rates of SVR and ETVR.</p><p><b>CONCLUSION</b>CHC patients who fail to respond to the initial course of standard IFN-based therapy may achieve SVR upon retreatment, especially those infected with the HCV genotype 1b.</p>

Molecular regulation of telomerase activity in aging

The process of aging is mitigated by the maintenance and repair of chromosome ends (telomeres), resulting in extended lifespan. This review examines the molecular mechanisms underlying the actions and regulation of the enzyme telomerase reverse transcriptase (TERT), which functions as the primary mechanism of telomere maintenance and regulates cellular life expectancy. Underpinning increased cell proliferation, telomerase is also a key factor in facilitating cancer cell immortalization. The review focuses on aspects of hormonal regulations of telomerase, and the intracellular pathways that converge to regulate telomerase activity with an emphasis on molecular interactions at protein and gene levels. In addition, the basic structure and function of two key telomerase enzyme components-the catalytic subunit TERT and the template RNA (TERC) are discussed briefly.

Estrogen deficiency reversibly induces telomere shortening in mouse granulosa cells and ovarian aging in vivo

Estrogen is implicated as playing an important role in aging and tumorigenesis of estrogen responsive tissues; however the mechanisms underlying the mitogenic actions of estrogen are not fully understood. Here we report that estrogen deficiency in mice caused by targeted disruption of the aromatase gene results in a significant inhibition of telomerase maintenance of telomeres in mouse ovaries in a tissue-specific manner. The inhibition entails a significant shortening of telomeres and compromised proliferation in the follicular granulosa cell compartment of ovary. Gene expression analysis showed decreased levels of proto-oncogene c-Myc and the telomerase catalytic subunit, telomerase reverse transcriptase (TERT), in response to estrogen deficiency. Estrogen replacement therapy led to increases in TERT gene expression, telomerase activity, telomere length and ovarian tissue growth, thereby reinstating ovary development to normal in four weeks. Our data demonstrate for the first time that telomere maintenance is the primary mechanism mediating the mitogenic effect of estrogen on ovarian granulosa cell proliferation by upregulating the genes of c-Myc and TERT in vivo. Estrogen deficiency or over-activity may cause ovarian tissue aging or tumorigenesis, respectively, through estrogen regulation of telomere remodeling.

Long-term toxicity test of rhIL-11 in cynomolgus / 第二军医大学学报

Objective:To investigate the long-term toxicity of recombinant human interleukin-11(rhIL-11) in cynomolgus. Methods: Eighteen cynomolgus were randomized into 4 groups: control group(2/sex), low dose group(2/sex), medium dose group(2/sex)， and high dose group(3/sex). The drug groups were sc adminstered 0.1, 0.3 and 1.0 mg/kg of rhIL-11 for 90 days with a 30-day recovery period. The clinical signs were observed, electrocardiogram, hematological, biochemical, urinary and immunological parameters were measured, organ masses were weighed, bone marrow and pathological histology were observed. Results: The food consumption, body mass of the drug groups were decreased, the body temperature was increased transiently. One of the low dose group showed restricted movements and tremors. One of the high dose group vomited and another died. Reduced red blood cell(RBC) count, hemoglobin(Hb) concentration, hematocrit(Hct), mean corpuscular volume(MCV), mean corpuscular hemoglobin(MCH), and mean corpuscular hemoglobin concentration(MCHC), dose-related increase of platelet(Plat) counts were present in drug groups. Biochemical examinations revealed dose-related decreases in serum alanine aminotransferase(ALT), aspartate aminotransferase(AST), lactate dehydrogenase(LDH), total proteins(TP) and albumin(Alb) increases in serum alkaline phosphatase(ALP) levels. Positive antibody responses were seen and circulatory immune complex(CIC) was significantly increased in all drug groups. Hypertropy of marrow megakaryocyocytes was noted in the medium and high dose groups. The heart and liver masses were slightly increased in all treatment groups. Treatment-related microscopic findings included dose-related degeneration in the liver and the kidney. The adverse effects were reversed by the end of the recovery period. Conclusion: The target organs and systems are blood, liver, kidney, immmue system and bone marrow. The toxicity injuries were reversible and the no-toxic-effect level is 0.1 mg/kg.

Long-term toxicity test of rhIL-11 in cynomolgus / 第二军医大学学报

Objective:To investigate the long-term toxicity of recombinant human interleukin-11(rhIL-11) in cynomolgus. Methods: Eighteen cynomolgus were randomized into 4 groups: control group(2/sex), low dose group(2/sex), medium dose group(2/sex)， and high dose group(3/sex). The drug groups were sc adminstered 0.1, 0.3 and 1.0 mg/kg of rhIL-11 for 90 days with a 30-day recovery period. The clinical signs were observed, electrocardiogram, hematological, biochemical, urinary and immunological parameters were measured, organ masses were weighed, bone marrow and pathological histology were observed. Results: The food consumption, body mass of the drug groups were decreased, the body temperature was increased transiently. One of the low dose group showed restricted movements and tremors. One of the high dose group vomited and another died. Reduced red blood cell(RBC) count, hemoglobin(Hb) concentration, hematocrit(Hct), mean corpuscular volume(MCV), mean corpuscular hemoglobin(MCH), and mean corpuscular hemoglobin concentration(MCHC), dose-related increase of platelet(Plat) counts were present in drug groups. Biochemical examinations revealed dose-related decreases in serum alanine aminotransferase(ALT), aspartate aminotransferase(AST), lactate dehydrogenase(LDH), total proteins(TP) and albumin(Alb) increases in serum alkaline phosphatase(ALP) levels. Positive antibody responses were seen and circulatory immune complex(CIC) was significantly increased in all drug groups. Hypertropy of marrow megakaryocyocytes was noted in the medium and high dose groups. The heart and liver masses were slightly increased in all treatment groups. Treatment-related microscopic findings included dose-related degeneration in the liver and the kidney. The adverse effects were reversed by the end of the recovery period. Conclusion: The target organs and systems are blood, liver, kidney, immmue system and bone marrow. The toxicity injuries were reversible and the no-toxic-effect level is 0.1 mg/kg.