A phase III randomized, double-blind, placebo-controlled trial of the denosumab biosimilar QL1206 in postmenopausal Chinese women with osteoporosis and high fracture risk.

The current study evaluated the efficacy and safety of a denosumab biosimilar, QL1206 (60 mg), compared to placebo in postmenopausal Chinese women with osteoporosis and high fracture risk. At 31 study centers in China, a total of 455 postmenopausal women with osteoporosis and high fracture risk were randomly assigned to receive QL1206 (60 mg subcutaneously every 6 months) or placebo. From baseline to the 12-month follow-up, the participants who received QL1206 showed significantly increased bone mineral density (BMD) values (mean difference and 95% CI) in the lumbar spine: 4.780% (3.880%, 5.681%), total hip :3.930% (3.136%, 4.725%), femoral neck 2.733% (1.877%, 3.589%) and trochanter: 4.058% (2.791%, 5.325%) compared with the participants who received the placebo. In addition, QL1206 injection significantly decreased the serum levels of C-terminal crosslinked telopeptides of type 1 collagen (CTX): -77.352% (-87.080%, -66.844%), and N-terminal procollagen of type l collagen (P1NP): -50.867% (-57.184%, -45.217%) compared with the placebo over the period from baseline to 12 months. No new or unexpected adverse events were observed. We concluded that compared with placebo, QL1206 effectively increased the BMD of the lumbar spine, total hip, femoral neck and trochanter in postmenopausal Chinese women with osteoporosis and rapidly decreased bone turnover markers. This study demonstrated that QL1206 has beneficial effects on postmenopausal Chinese women with osteoporosis and high fracture risk.

Prognostic role of apoptosis-related gene functional variants in advanced non-small-cell lung cancer patients treated with first-line platinum-based chemotherapy.

BACKGROUND: Single-nucleotide polymorphisms in apoptosis-related genes have been shown to play a role in the efficacy of platinum-based chemotherapy and may influence clinical outcomes. Our study aimed to evaluate the correlations of four functional single-nucleotide polymorphisms - FAS -670 A>G, FAS ligand -844 T>C, survivin -31 G>C, and survivin 9386 C>T - with drug response and clinical outcomes in advanced non-small-cell lung cancer patients who received platinum-based chemotherapy. MATERIALS AND METHODS: Polymorphisms were evaluated using the polymerase chain reaction-based restriction fragment-length polymorphism technique. RESULTS: Patients with the CC genotype of FAS -670 A>G had worse overall survival (OS) than those with the CT or TT genotype (P=0.044), with median OS values of 20.1 months, 22.8 months, and 26.0 months, respectively. Furthermore, progression-free survival was associated with the FAS -670 A>G polymorphism (P=0.032). In addition, patients with the TC and CC genotypes of survivin 9386 C>T experienced improved survival compared with patients with the TT genotype (median OS 31.4 months and 22.8 months, respectively). CONCLUSION: The functional FAS -670 A>G and survivin 9386 C>T polymorphisms are potential independent prognostic factors in advanced non-small-cell lung cancer patients treated with platinum-based chemotherapy.

Topo2A as a prognostic biomarker for patients with resectable esophageal squamous cell carcinomas.

Topoisomerase 2α (Topo2A) is a key enzyme in replication. It functions as a cell proliferation and cell cycle-specific marker and it is identified mainly in the interphase nuclei of proliferating cells. Many studies have shown that Topo2A protein expression is up-regulated in various cancers including esophageal cancer. However, to date, no studies have adequately addressed the prognostic value of Topo2A in patients with resectable esophageal squamous cell carcinoma (ESCC). Therefore, we conducted a large-scale retrospective study investigating the expression of Topo2A and the clinicopathological characteristics or prognosis of ESCC patients. Eight hundred and twenty-nine specimens of ESCC from patients who underwent complete esophageal cancer resection were evaluated using an immunohistochemical assay. Among them, 404 (48.7 %) cases with a score >2 were determined to be positive for Topo2A expression. Topo2A overexpression was significantly associated with poorer differentiation (P = 0.007) and perineural invasion (P = 0.046). The median progression-free survival (PFS) of 319 patients with Topo2A-positive expression and 336 patients with Topo2A-negative expression was 19.5 and 26.5 months, respectively (P = 0.000). The overall survival (OS) in patients with and without Topo2A expression was 34.0 and 44.5 months, respectively (P = 0.002). In the multivariate analysis, Topo2A overexpression was identified as an independent prognostic factor for PFS (P = 0.001) and OS (P = 0.009). We determined that Topo2A overexpression was not only associated with poorer differentiation and perineural invasion, but it could also act as an independent risk factor for ESCC.

p53 is an independent prognostic factor in operable esophageal squamous cell carcinoma: a large-scale study with a long follow-up.

The p53 protein is involved in many biological functions in cancer, such as cell cycle arrest, DNA repair, apoptosis, senescence, DNA metabolism, angiogenesis, and cellular differentiation. However, the association between p53 expression and clinicopathological findings or prognosis in esophageal squamous cell carcinoma (ESCC) is controversial. We designed a large-scale study of 830 operable ESCC patients with a long follow-up to investigate the relationship between p53 expression and the clinicopathological characteristics and prognosis of patients. Immunohistochemistry was used to detect p53 protein expression. When the patients were divided into two groups, a positive expression group and a negative expression group, p53-positive expression positively correlated with a poorer differentiation level (P = 0.044). The overexpression of p53 was associated with a more advanced clinical stage (P = 0.015). A total of 775 patients were available for survival analysis. The median OS of 160 patients who had p53-positive expression and 486 patients who had p53-negative expression were 58.8 and 46.3 months, respectively (P = 0.021); the median PFS of the two groups were 39.6 and 27.5 months, respectively (P = 0.015). Lymph node metastasis, gender, differentiation, depth of invasion, and p53 protein expression were proven to have an influence on both OS and PFS in a univariate analysis. In the multivariate analysis, p53-positive expression maintained its independent prognostic impact on OS (P = 0.048) and PFS (P = 0.039), as did lymph node metastasis, differentiation, and depth of invasion. We identified that p53 protein-positive expression can serve as an independent, unfavorable prognosis biomarker in ESCC.

Systematic evaluation of dose accumulation studies in clinical pharmacokinetics.

The amount of drug remaining after previous doses, or drug accumulation, is closely related to drug efficacy and safety. An accurate calculation of the accumulation index or ratio (R(ac)) is crucial for dose finding. However, in drug accumulation studies little consensus exists with regard to experimental design or data analysis. We conducted a systematic review of the literature to produce a detailed profile of drug accumulation studies of the last 30 years (1980-2011). Ninety-six articles comprising 122 studies were analyzed. A typical drug accumulation study enrolled 10 to 20 subjects randomly assigned into treatment groups of 1 or 2 dose levels to observe pharmacokinetic behaviors. The median washout period between single and multiple dosing was 7 days, and the dose interval was 1-2 elimination half-lives in non- or one-compartmental models. Generally, the number of repeated times of administration for multiple dosing was 7-14, and the median number of sampling time points was 11. Eight different methods were used to calculate R(ac). The most frequently used method, in 72.9% of the studies, was to set R(ac) equal to the ratio of the area under a plasma concentration-time curve (AUC) during a dosage interval at steady state to the AUC of a dosage interval after the first dose, i.e., R(ac) = AUC(0-τ,ss) / AUC(0-τ,1). The values of R(ac) in the included studies ranged from 0.85 to 18.8, and 68.03% were <2. We suggest that sample size estimation for an accumulation study should be similar to that of a bioequivalence study, and in most studies, 18-24 subjects will be needed. Appropriate calculation methods for R(ac) should be selected based on the experimental design and data characteristics. The crucial values for non-, weak, moderate, and strong accumulation can be set at R(ac) < 1.2, 1.2 ≤ R(ac) < 2, 2 ≤ R(ac) < 5, and R(ac) ≥ 5, respectively. Accumulations studies should also give more regard to drug metabolism and increased accumulation in kidney or liver damaged patients.

[Comparative pharmacokinetic analysis based on nonlinear mixed effect model].

Comparative pharmacokinetic (PK) analysis is often carried out throughout the entire period of drug development, the common approach for the assessment of pharmacokinetics between different treatments requires that the individual PK parameters, which employs estimation of 90% confidence intervals for the ratio of average parameters, such as AUC and Cmax, these 90% confidence intervals then need to be compared with the pre-specified equivalent interval, and last we determine whether the two treatments are equivalent. Unfortunately in many clinical circumstances, some or even all of the individuals can only be sparsely sampled, making the individual evaluation difficult by the conventional non-compartmental analysis. In such cases, nonlinear mixed effect model (NONMEM) could be applied to analyze the sparse data. In this article, we simulated a sparsely sampling design trial based on the dense sampling data from a truly comparative PK study. The sparse data were analyzed with NONMEM method, and the original dense data were analyzed with non-compartment analysis. Although the trial design and analysis methods are different, the 90% confidence intervals for the ratio of PK parameters based on 1000 Bootstrap are very similar, indicated that the analysis based on NONMEM is a reliable method to treat with the sparse data in the comparative pharmacokinetic study.

Increased expression of ErbB-2 in liver is associated with hepatitis B x antigen and shorter survival in patients with liver cancer.

Hepatitis B x antigen, or HBxAg, contributes importantly to the pathogenesis of hepatocellular carcinoma (HCC). Given that HBxAg constitutively activates beta-catenin and that upregulated ErbB-2 promotes beta-catenin signaling in other tumor types, experiments were designed to ask whether HBxAg was associated with upregulated expression of ErbB-2. When HBxAg positive and negative HepG2 cells were subjected to proteomics analysis, ErbB-2 was shown to be upregulated in HepG2X but not control cells. ErbB-2 was also strongly upregulated in HB infected liver, and weakly in some HCC nodules, where it correlated with HBxAg expression. Among tumor bearing patients, strong ErbB-2 staining in the liver was associated with dysplasia, and a shorter survival after tumor diagnosis. This implies that elevated ErbB-2 is an early marker of HCC. Treatment of HepG2X cells with ErbB-2 specific siRNA not only reduced ErbB-2 expression, but also reduced the expression of beta-catenin, suggesting that ErbB-2 contributed to the stabilization of beta-catenin. ErbB-2 specific siRNA also partially blocked the ability of HBxAg to promote DNA synthesis and growth of HepG2 cells. These results suggest that ErbB-2/beta-catenin up-regulation contributes importantly to the mechanism of HBxAg mediated hepatocellular growth.

Enhanced cell survival of Hep3B cells by the hepatitis B x antigen effector, URG11, is associated with upregulation of beta-catenin.

Intrahepatic expression of hepatitis B x antigen (HBxAg) is associated with the development of hepatocellular carcinoma (HCC), perhaps through trans-activation of selected cellular genes. When this was examined by PowerBlot analysis, upregulated levels of beta-catenin and several known beta-catenin effectors were observed in HBxAg-positive compared with HBxAg-negative HepG2 cells. When HBxAg was introduced into Hep3B cells, upregulated expression of wild-type beta-catenin was observed. This was also observed in Hep3B cells overexpressing the HBxAg upregulated gene, URG11. Upregulated expression of URG11 and beta-catenin correlated with HBxAg trans-activation function. Transient transfection assays with fragments of the beta-catenin promoter showed that it was activated by both HBxAg and URG11 and inhibited by URG11-specific small inhibitory RNA. The latter also inhibited the growth of Hep3BX cells in a serum-free medium, which correlated with depressed levels of beta-catenin. Activation of beta-catenin effector genes was observed in cells stably expressing HBxAg or overexpressing URG11 compared with control cells transfected with the pTOPFLASH reporter plasmid. Extensive costaining between HBxAg, URG11, and beta-catenin was observed in infected liver and HCC nodules, suggesting a close relationship in vivo. In conclusion, wild-type beta-catenin is activated by HBxAg, in part, through the upregulated expression of the HBxAg effector URG11. URG11 stimulates the beta-catenin promoter and hepatocellular growth and survival. These observations also suggest that URG11 may be a regulatory element in the beta-catenin signaling pathway and may be a target for chemoprevention of HCC.

[The effect of down regulating of p27 on the activity of hematopoietic progenitor cells derived from umbilical cord blood and bone marrow ex vivo].

OBJECTIVE: To compare p27 interfering effect on the proliferation and hematopoietic potential of hematopoietic progenitor cells (HPC) derived from human bone marrow (BM) and umbilical cord blood (UCB), and investigate the related mechanism. METHODS: CD34(+) cells sorted from human BM by flow cytometry and isolated from UCB by a magnetic isolation system were infected with retrovirus-p27 antisense cDNA (p27AS) and cultured with cocktail-cytokines. The cell proliferation capacities were detected by cell growth curve and DNA content analysis, and the hematopoietic potential by colony formation assay. The protein expression of p27 and CDK2 were measured with Western blot. CD34(+) cells infected with retrovirus-p27 sense cDNA (p27SE) and virus-green fluorescence protein (GFP) were used as the control. RESULTS: Comparing with groups of GFP and p27SE, p27AS showed to accelerate the expansion of UCB HPC significantly (P < 0.01), the cell number of p27AS, p27SE and GFP increased by 197.3 +/- 47.7-, 12.7 +/- 8.1- and 41.8 +/- 30.6- fold respectively by the end of the 9-day culture, the BM HPC increased by 36.0 +/- 22.3-, 8.7 +/- 6.8- and 14.1 +/- 10.4-fold respectively in the same time as UCB HPC. Cell cycle analysis showed p27AS mainly promoted S phase of BM and UCB HPC. S phase cell percentages of UCB HPC infected with p27AS, p27SE and GFP were (17.0 +/- 4.8)%, (2.0 +/- 0.8)% and (4.1 +/- 1.8)% and that of BM HPC were (8.4 +/- 4.4)%, (1.0 +/- 0.7)% and (3.8 +/- 1.4)% respectively. The yields of colony formation of p27AS for BM and UCB was higher than that for GFP (P < 0.05). Western blot demonstrated the expression of p27 reduced in the p27AS group, while CDK2 increased in the group. The virus infection rate, cell growth rate and colony forming yields of BM HPC was inferior to that of UCB HPC. CONCLUSIONS: p27 gene interfering could promote HPC proliferation, hematopoietic potential and the response to stimulations of UCB HPC is higher than that of BM HPC ex vivo. It seems that cell cycle controlled by p27 was related to CDK2.

Gadd45a expression induces Bim dissociation from the cytoskeleton and translocation to mitochondria.

Gadd45a, a p53- and BRCA1-regulated stress protein, has been implicated in the maintenance of genomic fidelity, probably through its roles in the control of cell cycle checkpoint and apoptosis. However, the mechanism(s) by which Gadd45a is involved in the induction of apoptosis remains unclear. We show here that inducible expression of Gadd45a protein causes dissociation of Bim, a Bcl2 family member, from microtubule-associated components and translocation to mitochondria. The Bim accumulation in mitochondria enhances interaction of Bim with Bcl-2, relieves Bax from Bcl-2-bound complexes, and subsequently results in release of cytochrome c into the cytoplasm. Suppression of endogenous Bim greatly inhibits Gadd45a induction of apoptosis. Interestingly, Gadd45a interacts with elongation factor 1alpha (EF-1alpha), a microtubule-severing protein that plays an important role in maintaining cytoskeletal stability, and inhibits EF-1alpha-mediated microtubule bundling, indicating that the interaction of Gadd45a with EF-1alpha disrupts cytoskeletal stability. A mutant form of Gadd45a harboring a deletion of EF-1alpha-binding domain fails to inhibit microtubule stability and to induce Bim translocation to mitochondria. Furthermore, coexpression of EF-1alpha antagonizes Gadd45a's property of suppressing cell growth and inducing apoptosis. These findings identify a novel link that connects stress protein Gadd45a to the apoptotic machinery and address the importance of cytoskeletal stability in apoptotic response to DNA damage.

Human S15a expression is upregulated by hepatitis B virus X protein.

The hepatitis B virus (HBV)-encoded X antigen (HBxAg) may contribute to the development of hepatocellular carcinoma (HCC) through the upregulated expression of selected cellular genes. To identify these genes, RNAs isolated from HBxAg-positive and -negative HepG2 cells were compared by PCR select cDNA subtraction. One gene overexpressed in HBxAg-positive cells by Northern and Western blotting is the ribosomal protein S15a. The S15a mRNA is 535 base pairs, encoding a protein 130 amino acids long with a molecular weight of 14.3 kDa. S15a expression was upregulated in HBV-infected livers, where it costained with HBxAg. Overexpression of S15a stimulated cell growth, colony formation in soft agar, and tumor formation in SCID mice. Hence, HBxAg upregulated the expression of S15a, the latter of which participates in the development of HCC, perhaps by altering the integrity of translation.

Upregulated expression of a unique gene by hepatitis B x antigen promotes hepatocellular growth and tumorigenesis.

Hepatitis B x antigen (HB x Ag) is a trans-activating protein that may be involved in hepatocarcinogenesis, although few natural effectors of HB x Ag that participate in this process have been identified. To identify additional effectors, whole cell RNA isolated from HB x Ag-positive and HB x Ag-negative HepG2 cells were compared by polymerase chain reaction select cDNA subtraction, and one clone, upregulated gene, clone 11 (URG11), was chosen for further characterization. Elevated levels of URG11 mRNA and protein were observed in HB x Ag-positive compared to HB x Ag-negative HepG2 cells. Costaining was observed in infected liver (P < 0.01). URG11 stimulated cell growth in culture (P < 0.01), anchorage-independent growth in soft agar (P < 0.001), and accelerated tumor formation (P < 0.01), and yielded larger tumors (P < 0.02) in SCID mice injected subcutaneously with HepG2 cells. These data suggest that URG11 is a natural effector of HB x Ag that may promote the development of hepatocellular carcinoma.

GADD45-induced cell cycle G2-M arrest associates with altered subcellular distribution of cyclin B1 and is independent of p38 kinase activity.

In response to DNA damage, the cell cycle checkpoint is an important biological event in maintaining genomic fidelity. Gadd45, a p53-regulated and DNA damage inducible protein, has recently been demonstrated to play a role in the G2-M checkpoint in response to DNA damage. In the current study, we further investigated the biochemical mechanism(s) involved in the GADD45-activated cell cycle G2-M arrest. Using the tetracycline-controlled system (tet-off), we established GADD45-inducible lines in HCT116 (wild-type p53) and Hela (inactivated p53 status) cells. Following inducible expression of the Gadd45 protein, cell growth was strongly suppressed in both HCT116 and Hela cells. Interestingly, HCT116 cells revealed a significant G2-M arrest but Hela cells failed to arrest at the G2-M phases, indicating that the GADD45-activated G2-M arrest requires normal p53 function. The GADD45-induced G2-M arrest was observed independent of p38 kinase activity. Importantly, induction of Gadd45 protein resulted in a reduction of nuclear cyclin B1 protein, whose nuclear localization is critical for the completion of G2-M transition. The reduced nuclear cyclin B1 levels correlated with inhibition of Cdc2/cyclin B1 kinase activity. Additionally, overexpression of cyclin B1 substantially abrogated the GADD45-induced cell growth suppression. Therefore, GADD45 inhibition of Cdc2 kinase activity through alteration of cyclin B1 subcellular localization may be an essential step in the GADD45-induced cell cycle G2-M arrest and growth suppression.

ATF3 induction following DNA damage is regulated by distinct signaling pathways and over-expression of ATF3 protein suppresses cells growth.

Mammalian cells have a remarkable diverse repertoire of response to genotoxic stress that damage DNA. Cellular responses to DNA damaging agents will initially exhibit gene induction, which is regulated by complex mechanism(s) and probably involves multiple signaling pathways. In this paper, we demonstrate that induction of ATF3 protein, a member of the ATF/CREB family of transcription factors, by ionizing radiation (IR) requires normal cellular p53 function. In contrast, induction of ATF3 after UV radiation (UV) or Methyl methanesulphonate (MMS) is independent of p53 status. Induction of ATF3 by DNA damage is rapid, transient, and through a transcriptional mechanism. The ATF3 promoter is induced by UV and MMS, but not by IR. In addition, ATF3 promoter can be activated by MEKK1, an upstream activator of the ERK and JNK kinase pathway, but not induced following p53 expression. Those results indicate that regulation of ATF3 induction after DNA damage utilizes both the p53-dependent and -independent pathways, and may also involve MAP kinase signaling pathways. Using the tetracycline-inducible system (tet-off), we have found that over-expression of ATF3 protein moderately suppresses cell growth. Interestingly, over-expression of ATF3 protein is able to slow down progression of cells from G1 to S phase, indicating that ATF3 protein might play a negative role in the control of cell cycle progression.