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Human A-defensin-1 (HNP1), a small antimicrobial peptide, shows cytotoxicity to tumor cells in vitro and inhibitory activity for pathologic neovascularization in vivo. Here, we did a gene therapy with a plasmid that expresses a secretable form of HNP1 for assaying its antitumor activity. The expression and secretion of HNP1 were determined by reverse transcription-PCR and ELISA in vitro. We found that expression of HNP1 in A549 tumor cells caused significant growth inhibition. This effect is most likely cell autonomous, as a significant amount of recombinant HNP1 protein was found to be accumulated in the cytoplasm by immunohistochemical staining using an anti-HNP1 antibody and the supernatant containing secreted HNP1 failed to produce any noticeable antitumor activity. Flow cytometry and Hoechst 33258 staining showed that the number of apoptotic cells among the A549 cells expressing recombinant HNP1 proteins was significantly greater than that of the nontransfected control cultures, suggesting that this growth-inhibitory activity was due to an apoptotic mechanism triggered by the intracellular HNP1. The antitumor activity of intracellularly expressed HNP1 was also shown in vivo. Decreased microvessel density and increased lymphocyte infiltration were observed in tumor tissue from HNP1-treated mice through histologic analysis. These results indicate that intracellularly expressed HNP1 induces tumor cell apoptosis, which inhibits tumor growth. The antiangiogenesis effect of HNP1 may contribute to its inhibitory activity in vivo, and HNP1 might involve the host immune response to tumor. These findings provide a rationale for developing HNP1-based gene therapy for cancer. [Mol Cancer Ther 2008;7(6):1588 -97]

Purpose: Human neutrophil peptides (HNP1-3), small molecular antimicrobial peptides, are expressed within tumors and associated with tumor necrosis and inhibition of angiogenesis. Recent investigations have suggested that HNP1-3 are likely to be involved in the host immune responses to tumors. Experimental Design: We used recombinant pSec-HNP1, which expresses a secretable form of HNP1, to obtain expression of HNP1 in the tumor milieu in immunocompetent mice to explore the possible roles of HNP1 in tumor immunity. The antitumor effects were investigated in established CT26 colon cancer and 4T1 breast cancer models. Results: HNP1-mediated chemotactic and activating effects on immature dendritic cells were detected both in vitro and in vivo. Intratumoral expression of HNP1 resulted in not only significant tumor growth inhibition but also increased CTL infiltration within tumors. Adoptive transfer of splenocytes and a 51 Cr release assay revealed specific cellular immune responses. Furthermore, increased antibodies were also found in sera from pSec-HNP1-treated mice supporting specific humoral immune responses. Increased apoptosis and decreased angiogenesis were also shown in treated tumors. Conclusions: These findings indicate that HNP1 can exert multiple antitumor effects through different mechanisms; more importantly, HNP1 mediates host immune responses to tumors in situ through the recruitment and subsequent activation of immature dendritic cells and thus shows promising potential in cancer therapy. (Clin Cancer Res 2009;15(22):6901-11)

The expression of survivin, an inhibitor of apoptosis can be seen in most tumors and is correlated with the angiogenic factor vascular endothelial growth factor (VEGF). But little is known about their contribution in small-cell lung cancer (SCLC). This study was designed to investigate the expression of survivin and VEGF in SCLC, and to explore their correlation with clinical-pathological feature and prognosis. Forty-five patients with pathological histology of SCLC were entered into this study. Forty-five cases of matched adjacent non-tumor samples and 10 samples of operated patients with benign lung tumor were also included as control. The expression of survivin and VEGF was detected by immunohistochemistry (IHC, SP). These two sets of data were processed and tested for correlation with major patients' characteristics, and overall survival. The correlations between survivin and VEGF expressions and the clinical-pathological features were evaluated by chi-square test. The correlation between survivin and VEGF expressions was analyzed by Spearman's rank correlation test; the overall survival was analyzed by the Kaplan-Meier method; and the relationship between clinical and pathological features and overall survival was analyzed by the Cox proportional hazard models. Positive expression rate of survivin and VEGF was significantly higher in SCLC than those of adjacent non-tumor tissues and benign lung tumor tissues (73.3 vs. 15.6 vs. 0 %, P < 0.05) and (75.6 vs. 20 vs. 0 %, P < 0.05), respectively. Survivin and VEGF expressions were significantly associated with lymph node metastasis (P = 0.003, 0.011) and clinical stage (P = 0.006, 0.021). The expression of survivin was significantly coincident with the expression of VEGF (r = 0.644, P = 0.000). The median overall survival in survivin positive group and VEGF positive group was significantly shorter than those in survivin negative and VEGF negative group, respectively (log-rank P = 0.000). Moreover, multivariate analysis showed that survivin expression (HR 0.224; 95 % CI 0.074-0.675; P = 0.008) and VEGF expression (HR 0.172; 95 % CI 0.054-0.559; P = 0.003) were statistically independent predictive factors of poorer prognosis for SCLC patients. Our results indicated that survivin and VEGF were over-expressed in small-cell lung cancer, each of them may be an independent poor prognostic factor.

Purpose: Previous studies indicated that humoral or cellular immunity against murine vascular endothelial growth factor 2 (mFlk-1) was elicited to inhibit tumor growth. Here we describe a genetic fusion vaccine, pMBD2-mFlk-1, based on the targeting of a modified mFlk-1 to antigenpresenting cells by a murine h-defensin 2 (MBD2) protein to induce both humoral and cellular immunity against mFlk-1, with the targeting especially focused on immature dendritic cells. Experimental Design:The protective and therapeutic antitumor immunity of the fusion vaccine was investigated in mouse models. Antiangiogenesis effect was detected by immunohistochemical staining and alginate-encapsulate tumor cell assay. The mechanisms of the fusion vaccine were primarily explored by detection of autoantibodies and CTL activity and confirmed by the deletion of immune cell subsets. Results: The fusion vaccine elicited a strong protective and therapeutic antitumor immunity through antiangiogenesis in mouse models, and this worked through stimulation of an antigenspecific CD8 + T-cell response as well as a specific B-cell response against mFlk-1. The findings were confirmed by depletion of immune cell subsets and in knockout mice. Conclusion: Our study showed that a fusion vaccine based on self immune peptide (MBD2) and self antigen (mFlk-1) induced autoimmunity against endothelial cells, resulting in inhibition of tumor growth, and could be further exploited in clinical applications of cancer immunotherapy.

BackgroundAlthough hyperphosphatemia is deemed a risk factor of the progression of chronic kidney disease (CKD), it remains unclear whether the normal range of serum phosphorus likewise deteriorates CKD. A propensity score analysis was applied to examine the causal effect of the normal range of serum phosphorus on the incidence of end-stage renal disease (ESRD).MethodsA retrospective CKD cohort of 803 participants in a single institution was analyzed. Propensity score was estimated using 22 baseline covariates by multivariate binary logistic regression for the different thresholds of time-averaged phosphorus (TA-P) in the normal range of serum phosphorus incremented by 0.1 mg/dL from 3.3 to 4.5 mg/dL.ResultsThe incidence rate of ESRD was 33.9 per 1,000 person-years over median follow-up of 4.3 years. Total patients showed the mean baseline phosphorus of 3.37 mg/dL and were divided to quartile. The higher quartile was associated with the parameters consistent with the advancement of CKD. A stratified Cox regression showed the highest hazard ratio (HR) at TA-P 3.4 mg/dL (HR 17.60, 95% CI 3.92–78.98) adjusted for baseline covariates such as sex, age, diabetic nephropathy, estimated GFR, serum albumin, Na-Cl, phosphorus, LDL-C and proteinuria. Adjusted HRs remained high up to TA-P 4.2 mg/dL (HR 2.22, 95% CI 1.33–3.71). After propensity score matching conducted at the thresholds of TA-P 3.4, 3.6, 3.8 and 4.0 mg/dL, the higher levels of TA-P showed the higher HRs by Kaplan-Meier analysis (p < 0.05 by stratified log-rank test). The numbers needed to treat were calculated as 3.9 to 5.3 over 5 years.ConclusionsThe propensity score analysis shows that even the normal range of serum phosphorus clearly accelerates CKD progression to ESRD. Our results encourage clinicians to target serum phosphorus to inhibit CKD progression in the manner of ‘the lower the better.’

PICT-1 is an essential ribosome biogenesis factor whose loss induces p53 accumulation and apoptosis. Here, we show that DNA damage changes PICT-1 localization and decreases PICT-1 protein levels via the proteasome pathway. Two important phosphatidylinositol 3-kinase-like kinases (PIKKs), ataxia-telangiectasia mutated (ATM) and the Ku70 subunit of DNA-dependent protein kinase (DNA-PK), co-localize and interact with PICT-1 in the nucleolus. Computational prediction of phosphorylation sites and detection using an anti-phospho-substrate antibody suggest that PICT-1 might be a substrate of PIKKs. PICT-1 S233 and T289 were identified as the key phosphorylation sites in this pathway, as mutating both to alanine abolished UVB-induced increase of PICT-1 phosporylation. Inhibition of PIKKs or ATM (with wortmannin and KU55933, respectively) prevented the agglomeration and degradation of PICT-1, suggesting that ATM is a key regulator of PICT-1. PICT-1(S233A, T289A) demonstrated marked resistance to DNA damage-induced agglomeration and loss of PICT-1. Phosphomimetic PICT-1 (S233D, T289D) showed a different nuclear distribution and was more rapidly degraded after DNA damage than wild-type PICT-1. Furthermore, both phosphorylation and degradation of PICT-1 released RPL11 from the nucleolus to the nucleoplasm, increased binding of RPL11 to MDM2, and promoted p53 accumulation and apoptosis in an ATM-dependent manner after DNA damage. These data indicate that PICT-1 is a major nucleolar sensor of the DNA damage repair response and an important upstream regulator of p53 via the RPL11-MDM2-p53 pathway.

The ER-α gene polymorphisms have been reported to be associated with uterine leiomyoma (ULM) risk. The purpose of the present study was to perform a meta-analysis to explore the polymorphisms in the ER-α gene and the risk of ULM. A comprehensive search for relevant articles was conducted in MEDLINE (Ovid), PubMed, Embase, Springer, EBSCO, Web of Science, CNKI, Wanfang, Weipu, and Google Scholar. A total of nine articles were identified. Among the nine articles, 11 cohorts reported the PvuII polymorphism and six reported the XbaI polymorphism. The strength of the relationships between the polymorphisms in ER-α (PvuII and XbaI) and the risk of ULM was assessed by odds ratios (ORs). The studies provided overall OR estimates for PvuII and XbaI, leading to a pooled OR of 1.41 (PP+Pp vs. pp: OR = 1.41, 95 % confidence interval (95 %CI) = 1.02-1.96, P = 0.04), 1.13 (XX+Xx vs. xx: OR = 1.13, 95 %CI = 0.91-1.41, P = 0.25), respectively. The PvuII polymorphism in the ER-α gene may be a risk factor for ULM. Future studies are needed to validate our conclusions.