The status of carrier and prenatal diagnosis of haemophilia in China

Haemophilia A (HA) and haemophilia B (HB) are the most common X-linked inherited bleeding disorders. It is important to detect the carrier women in families with HA/HB and subsequent antenatal diagnosis of confirmed carriers. This study consists of 102 HA families which include 68 mothers for prenatal diagnosis and 107 female relatives for carrier diagnosis, and 29 HB families which include 16 mothers and 31 female relatives respectively. The rapid fluorescent PCR with two groups of different combined polymorphism markers was applied for linkage analysis in HA and HB families respectively. The Amelogenin gene was added to help the detection of gender diagnosis. Gene sequencing was also used to detect the mutations directly. There were 37 causative F8C mutations (23 novel) and 24 causative F9C mutations (eight novel) found in this cohort of patients. Few of the women could not be diagnosed due to homologous recombination and/or inability to locate the mutation. Complicated cases have been found in some families. With regard to carrier and prenatal diagnosis, it was considered that genetic diagnosis by linkage analysis and direct sequencing was successful. Some special families might require combination of the linkage analysis and gene sequence for a successful diagnosis. New intragenic SNP and STR sites special to Chinese population need to be discovered.

The polymorphisms in the VHL and HIF1A genes are associated with the prognosis but not the development of renal cell carcinoma

BACKGROUND

The von Hippel-Lindau (VHL) tumor suppressor gene and hypoxia-inducible factor-1α (HIF1A) play a pivotal role in renal carcinogenesis. This study was aimed to clarify the influence of VHL and HIF1A polymorphisms on renal cell cancer (RCC) susceptibility and survival.

SUBJECTS AND METHODS

We genotyped four potentially functional single-nucleotide polymorphisms (rs779805 in VHL and rs11549465, rs11549467, and rs2057482 in HIF1A) and assessed their associations with RCC risk, clinicopathologic parameters in a case-control study of 620 patients and 623 controls, and the prognosis of RCC in a cohort of 311 patients.

RESULTS

No significant differences in VHL or HIF1A genotypes were observed between RCC cases and controls. However, individuals with ≥2 variant alleles of the four polymorphisms were associated with less frequent lymph node metastasis and lower clinical stage (P = 0.032 and P = 0.041, respectively). And the number of variant alleles was associated with improved survival in a dose-response manner (P(trend) = 0.013). Furthermore, multivariate Cox regression analysis showed that the number of variant alleles (≥1 versus 0) was an independent prognostic factor for RCC survival (P = 0.036) together with clinical stage and tumor grade.

CONCLUSION

The VHL and HIF1A polymorphisms may not influence RCC susceptibility but may jointly influence RCC progression and survival.

Clinical and genetic characterization of complete androgen insensitivity syndrome in a Chinese family

We studied a family with two cousins who were diagnosed with complete androgen insensitivity syndrome, an X-linked disorder caused by mutations in the androgen receptor gene. A pedigree analysis and a molecular study using PCR and DNA sequencing clarified each female family member's androgen receptor status and revealed a mutation consisting of the deletion of exon 2 and surrounding introns of the androgen receptor gene. Based on the relative nucleotide positions, we concluded that the deletion mutation in exon 2 and its surrounding introns was approximately 6000 to 7000 bp. This mutation, never previously fully characterized using DNA sequencing, was responsible for complete androgen insensitivity syndrome in this family. Pedigree analysis with a molecular study of the androgen receptor gene in affected families facilitates genetic counseling provided to family members.

Association of IL-4 -590 T>C polymorphism and risk of renal cell carcinoma in a Chinese population

Interleukin 4 (IL-4) is a typical pleiotropic T helper 2 (Th2) cytokine. This cytokine is a critical mediator of the Th1/Th2 balance and apoptosis potential and involved in the process of inflammation-mediated carcinogenesis in human organs, including renal cell carcinoma (RCC). The effects of functional promoter polymorphism of the IL-4 gene on risk of RCC in Chinese are still unknown. In this study, we genotyped functional polymorphism in IL-4-590 T>C in a hospital-based case-control study of 340 patients with diagnosed RCC and 342 cancer-free controls in a Chinese population. Compared with IL-4-590 TT genotype, the CC genotype had a significantly decreased RCC risk [adjusted odds ratio (OR) = 0.44, 95% confidence interval (CI) = 0.22-0.89]. Furthermore, a significant decreased risk of RCC was found in the combined variant genotypes CT + CC compared with the TT genotype (adjusted OR = 0.68, 95% CI = 0.50-0.93). The IL-4 C allele frequency was 0.178 among the cases and 0.237 among the controls, and the difference was statistically significant (P = 0.007). These results suggest that the IL-4-590 T>C polymorphism is involved in susceptibility to developing RCC in Chinese populations. Larger studies are warranted to validate our findings.

Urinary BLCA-4 is highly specific for detection of bladder cancer in Chinese Han population and is related to tumour invasiveness

BLCA-4 is currently the most sensitive and specific urinary marker for bladder cancer. As the incidence of bladder cancer varies by ethnic and territory, we tended to evaluate the feasibility of bladder cancer detection using urinary BLCA-4 in Chinese Han nationality. Urines from 79 bladder cancer patients, 31 urinary tract infection patients and 29 normal controls were included. Tissue specimens of 53 bladder cancers, 24 pathologically normal tumour- adjacent urothelium and 15 healthy controls were involved. BLCA-4 antibody was produced and applied in an indirect ELISA assay for urine samples and immunohistochemistry study in tissue samples. Urinary BLCA-4 was significantly higher in the bladder cancer group (P=0.0001). The level was in no relation to age, gender, growth pattern, grade or stage. Discrepant to reported data, a cut-off value of 1.7×10⁻⁴ A was acquired here, which yields a sensitivity of 97.37% and specificity of 100%. Muscle invasiveness was related to a higher BLCA-4 level (P=0.0175). Tumour tissues were also scored higher in staining (P=0.0001), yet this was not related to invasiveness. In 41.67% of adjacent normal tissue we found positive BLCA-4 expression. Urinary BLCA-4 was also highly specific in bladder cancer detection in the Chinese, with additional indicative value in muscle invasiveness detection. A cut-off value of 1.7×10⁻⁴ A may be more adaptive to Chinese Han population.

Recombinant N-terminal part of bovine herpesvirus 1 ICP27 protein: its preparation, purification, and use for raising specific antiserum

Recombinant N-terminal part of bovine herpesvirus-1 (BoHV-1) ICP27 protein fused with thioredoxin and His-tag ("the recombinant protein") expressed in Escherichia coli was purified by the Ni2+-NTA affinity chromatography and used for the preparation of antiserum by immunization of rabbits. The antiserum recognized the recombinant protein in Western blot analysis and was able to detect BoHV-1 ICP27 in the nucleoli of BoHV-1-infected MDBK cells. These results showed that such an antiserum could serve as a valuable tool in further studies of the functions of BoHV-1 ICP27.

KEYWORDS

Bovine herpesvirus 1, ICP27, recombinant protein, antiserum, immunofluorescence assay.

The adipokine zinc-alpha2-glycoprotein (ZAG) is downregulated with fat mass expansion in obesity

INTRODUCTION

Zinc-alpha2-glycoprotein (ZAG) is a novel adipokine, which may act locally to influence adipocyte metabolism. This study assessed the effect of increased adiposity on ZAG expression in adipose tissue in human subjects. The study also examined the association between ZAG and adiponectin expression in human adipose tissue, and whether ZAG modulates adiponectin secretion by human adipocytes.

METHODS

Adipose tissue (visceral and subcutaneous) was collected from human subjects with a wide range of BMIs. Human Simpson-Golabi-Behmel syndrome (SGBS) adipocytes were used for in vitro studies. ZAG mRNA levels were quantified by real-time PCR and protein by Western blotting.

RESULTS

In human subjects, ZAG mRNA level was negatively correlated with BMI (r = -0.61, P < 0.001, n = 23, visceral; r = -0.6, P < 0.05, n = 14, subcutaneous) and fat mass (r = -0.62, P < 0.01, visceral; r = -0.6, P < 0.05, subcutaneous). Negative associations were also found between ZAG mRNA and insulin resistance parameters including plasma insulin (r = -0.65, P < 0.001, visceral; r = -0.55, P < 0.05, subcutaneous) and homeostasis model of insulin resistance (HOMA-IR) (r = -0.65, P < 0.001, visceral; r = -0.52, P = 0.055, subcutaneous), and C reactive protein (CRP) (r = -0.46, P < 0.05, visceral; r = -0.53, P < 0.05, subcutaneous). However, ZAG mRNA was positively correlated with adiponectin (r = 0.5, P < 0.05, visceral; r = 0.82, P < 0.001, subcutaneous) but negatively associated with leptin mRNA (r = -0.42, P < 0.05, visceral; r = -0.54, P < 0.05, subcutaneous). ZAG secretion by differentiated human adipocytes was abundant. Addition of recombinant ZAG stimulated adiponectin release from human adipocytes.

CONCLUSION

ZAG gene expression in adipose tissue is downregulated with increased adiposity and circulating insulin. ZAG mRNA is positively correlated with adiponectin mRNA, and ZAG enhances adiponectin production by human adipocytes. We suggest that ZAG is linked to obesity and obesity-related insulin resistance.

Silencing of HIF-1alpha suppresses tumorigenicity of renal cell carcinoma through induction of apoptosis

Hypoxia-inducible factor-1alpha (HIF-1alpha) is a main responder to intracellular hypoxia and is overexpressed in many human cancers, including renal cell carcinoma (RCC). To better understanding of the role of HIF-1alpha in the tumorigenicity of RCC, we used short-hairpin RNA (shRNA) interference to inhibit HIF-1alpha expression in the human renal cancer cell line, Caki-1 and OS-RC-2. Silencing of HIF-1alpha significantly reduced the expression of HIF-1alpha in both of renal cancer cell lines. In vitro downregulation of HIF-1alpha inhibited Caki-1 and OS-RC-2 cell growth, migration and invasion. The results further showed that HIF-1alpha silencing resulted in caspase-dependent apoptosis of Caki-1 and OS-RC-2 through regulation of PI3K/Akt pathway and Bcl-2-related proteins expression. In vivo animal studies showed that tumor growth was significantly inhibited in HIF-1alpha shRNA-transfected RCC. Intratumor gene therapy with polyethylenimine-loaded HIF-1alpha shRNA also resulted in tumor growth suppression. Thus, this study demonstrates that downregulation of HIF-1alpha could suppress tumorigenicity of RCC through induction of apoptosis, and HIF-1alpha shRNA may be a promising strategy for the treatment of RCC.

SELDI-TOF-MS-based serum proteomic screening in combination with CT scan distinguishes renal cell carcinoma from benign renal tumors and healthy persons

In order to identify the proteomic differences between renal cell carcinoma (RCC) and benign renal tumors, we analyzed 168 serum samples from 65 RCC patients, 34 patients with benign renal tumors, and 69 healthy persons using the IMAC-Cu2+ ProteinChip system by surface enhanced laser desorption/ionization mass spectrometry technology. Two decision trees were generated by Biomarker Pattern software to distinguish between RCC versus healthy and RCC versus patients with benign tumors, respectively. Although the sensitivity and specificity of the RCC vs. healthy decision tree were 97.6% and 95.7%, respectively, it could not be used to distinguish RCC from benign renal tumors. The sensitivity of a blind test process using RCC, benign tumors and healthy persons were 92%. The specificity of the test process was 35.3% for benign tumors and 95.5% for healthy persons. The sensitivity and specificity of the RCC-Benign tumors decision tree were 85.7% and 95.5%, respectively. The blind test process using RCC, benign tumors and healthy persons also showed significant results. The sensitivity was 90.0%. The specificity was 95.7% for healthy persons and 90.0% for benign tumors. Combining these data with the results of CT scanning, the sensitivity can be improved over the use of either CT and decision tree analysis and the specificity may reach 100%. Two peaks with molecular masses of 3887.11 Da and 11079.8 Da were detected that are potentially useful for the diagnosis or screening of RCC. It was found that these two peaks can be used, not only to distinguish the RCC vs. healthy cases, but also to distinguish RCC from benign renal tumors. In combination with CT scanning, the sensitivity and specificity of the diagnosis of renal tumors can be improved. However, the decision tree constructed for RCC and healthy persons may not present good specificity for use in distinguishing malignant from benign renal tumors.

Using a minigene approach to characterize a novel splice site mutation in human F7 gene causing inherited factor VII deficiency in a Chinese pedigree

Factor VII deficiency which transmitted as an autosomal recessive disorder is a rare haemorrhagic condition. The aim of this study was to identify the molecular genetic defect and determine its functional consequences in a Chinese pedigree with FVII deficiency. The proband was diagnosed as inherited coagulation FVII deficiency by reduced plasma levels of FVII activity (4.4%) and antigen (38.5%). All nine exons and their flanking sequence of F7 gene were amplified by polymerase chain reaction (PCR) for the proband and the PCR products were directly sequenced. The compound heterozygous mutations of F7 (NM_000131.3) c.572-1G>A and F7 (NM_000131.3) c.1165T>G; p.Cys389Gly were identified in the proband's F7 gene. To investigate the splicing patterns associated with F7 c.572-1G>A, ectopic transcripts in leucocytes of the proband were analyzed. F7 minigenes, spanning from intron 4 to intron 7 and carrying either an A or a G at position -1 of intron 5, were constructed and transiently transfected into human embryonic kidney (HEK) 293T cells, followed by RT-PCR analysis. The aberrant transcripts from the F7 c.572-1G>A mutant allele were not detected by ectopic transcription study. Sequencing of the RT-PCR products from the mutant transfectant demonstrated the production of an erroneously spliced mRNA with exon 6 skipping, whereas a normal splicing occurred in the wide type transfectant. The aberrant mRNA produced from the F7 c.572-1G>A mutant allele is responsible for the factor VII deficiency in this pedigree.

REG1A predicts recurrence in stage Ta/T1 bladder cancer

AIMS

Stage Ta/T1 urothelial carcinoma of the bladder (Ta/T1 BC) has a marked tendency to recur. Regenerating protein 1 A (REG1A) has been reported to be expressed in human cancers, and it may be positively correlated with patient's prognosis. The aim of the present study was to evaluate the prognostic value of REG1A in Ta/T1 BC.

METHODS

Immunohistochemistry was done on 110 paraffin-embedded specimens of human Ta/T1 BC to detect the proteins REG1A, PCNA and MMP2. The relationships between REG1A expression and the clinical-pathological characteristics of Ta/T1 BC patients were evaluated.

RESULTS

Sixty-five out of 110 specimens were REG1A-positive. Grade and expression levels of MMP2 and REG1A were significantly correlated with the recurrence rate. REG1A expression (Hazard ratio: 3.1; 95% CI: 1.1-8.5; P=0.030) was an independent predictor of recurrence rate in multivariate Cox regression analysis. A significant association between REG1A expression and MMP2 expression (P=0.023) was also observed.

CONCLUSION

Expression of REG1A is an independent predictor of recurrence in Ta/T1 BC.

A novel mouse model of human breast cancer stem-like cells with high CD44+CD24-/lower phenotype metastasis to human bone

Abstract #4155

Background: At present, our understanding of the development of bone metastasis is limited. Therefore, little progress has been made in preventing skeletal metastasis in the breast cancer patient. A satisfactory animal model that avoids the species-specific factor and simultaneously shares similarities to the clinical pathophysiological progression of breast cancer metastasizing to bone is unavailable. A subpopulation (CD44+/CD24-/lower) of breast cancer cells possesses stem/progenitor cell properties (cancer stem-like cell). CD44 potentiates the adherence of metastatic breast cancer cells to bone marrow endothelial cells. In the present study, we used hepatocyte growth factor to enhance the proportion of CD44+/CD24-/lower subpopulation in the human breast cancer cell line MDA-MB-231. We used these human breast cancer stem-like cells and implantation of human bone to build a novel human-source model of human breast cancer skeletal metastasis.&#x2028; Methods: The human breast cancer cell line MDA-MB-231 was cultured in serum-free DMEM-F12 supplemented with growth factors. Cells in different subpopulations were separated by Percoll gradient centrifugation and incubated in the presence of 50 ng/mL hepatocyte growth factor. The proportion of CD44+/CD24-/lower subpopulation in the human breast cancer cell line MDA-MB-231 was detected with flow cytometry. Before injection with human breast cancer stem-like cells, the experimental animals were implanted with human bone in the right or left dorsal flanks. Animals in Groups A, B, and C were injected with 1 X 105, 1 X 106 human breast cancer stem-like cells, and 1 X 106 parental MDA-MB-231 cells, respectively. A positive control group (D) without implantation of human bone (non-human source model) was also injected with 1 X 106 MDA-MB-231 cells. A group of negative controls (E) with human bone implantation was injected with isotonic sodium chloride. For each group, Micro-SPECT was performed at weeks 4 and 7, and all animals were sacrificed at week 8. Immunohistochemistry was performed for CD34, CD105, SMA, CD44, CD24, CK, CXCR4, and OPN. mRNA levels of CD44, CD24, CXCR4, and OPN in bone metastasis tissues were analyzed by real-time quantitative polymerase chain reaction.&#x2028; Results: New vessels and connective tissue were found on the surface of implanted human bones and cells stained positive for antibodies against human CD105, SMA, and CD34, indicating that implanted human bones were viable and functional. Histologic and immunohistochemical analysis confirmed the metastases as cancer cells. Importantly, the results demonstrated that cells in implanted human bones of group B, which received 1 X 106 cancer stem-like cells, stained strongly positive for CD44, CXCR4, and OPN, whereas that of other groups showed no or minimum staining. Moreover, group B had the highest incidence of human bone metastasis (77.8%, P = 0.0230) and no accompaniment of other tissue metastasis. The real-time polymerase chain reaction (PCR) showed an increase of CD44 mRNA in metastatic bone tissues in group B compared with that of groups C and D (15.2- and 21.1-fold, respectively). The mRNA levels of CXCR4 and OPN (8.4- and 28.4-fold, respectively) in bone metastasis tissues of group B were all higher than that of groups C and D (4.8- and 11.6-fold; respectively). The levels of CD24 mRNA in group B were lowest, measuring only 30 percent of that in groups C and D.&#x2028; Conclusion: This study indicates that in the novel human source model of breast cancer, breast cancer stem-like cells demonstrate a higher human bone-seeking ability, which may contribute to increase metastasis incidence and attenuate species-specific influences. Its mechanism might be related to the higher expressions of CD44, CXCR4 and OPN, and the lower expression of CD24 in breast cancer stem-like cells. The model shares more similarities with clinical pathological features of bone metastatic patients. It will be helpful for further study of the mechanisms and subclinical diagnosis of bone metastasis.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4155.