Kinase Insert Domain Receptor Gene Research Articles

The KDR Gene rs2071559 and the VEGF Gene rs6921438 May Be Associated with Diabetic Nephropathy in Caucasians with Type 2 Diabetes Mellitus.

The aim of our study was to investigate an association between polymorphisms of either the VEGF (vascular endothelial growth factor) gene (rs6921438) or the KDR (kinase insert domain receptor) gene (rs2071559, rs2305948) and DN (diabetic nephropathy) in Caucasians with T2DM (type 2 diabetes mellitus). The second aim was to investigate the effect of either the VEGF gene (rs6921438) or the KDR gene (rs2071559, rs2305948) on the immune expression of either VEGF or KDR in the renal tissues of T2DM subjects (to test the functional significance of tested polymorphisms). The study included 897 Caucasians with T2DM for at least ten years (344 patients with DN and 553 patients without DN). Each subject was genotyped and analyzed for KDR (rs1617640, rs2305948) and VEGF (rs6921438) polymorphisms. Kidney tissue samples taken from 15 subjects with T2DM (autopsy material) were immunohistochemically stained for the expression of VEGF and KDR. We found that the rs2071559 KDR gene was associated with an increased risk of DN. In addition, the GG genotype of the rs6921438 VEGF gene had a protective effect. We found a significantly higher numerical area density of VEGF-positive cells in T2DM subjects with the A allele of the rs6921438-VEGF compared to the homozygotes for wild type G allele (7.0 ± 2.4/0.1 mm2 vs. 1.24 ± 0.5/0.1 mm2, respectively; p < 0.001). Moreover, a significantly higher numerical area density of KDR-positive cells was found in T2DM subjects with the C allele of rs2071559 (CC + CT genotypes) compared to the homozygotes for wild type T allele (9.7± 3.2/0.1 mm2 vs. 1.14 ± 0.5/0.1 mm2, respectively; p < 0.001) To conclude, our study showed that the presence of the C allele of the rs2071559 KDR gene was associated with a higher risk of DN, while the G allele of the rs6921438-VEGF conferred protection against DN in Slovenian T2DM subjects.

Implication of KDR Polymorphism rs2071559 on Therapeutic Outcomes and Safety of Postoperative Patients with Gastric Cancer Who Received S-1-Based Adjuvant Chemotherapy: A Real-World Exploratory Study.

Regimens of S-1-based adjuvant chemotherapy are of great significance in attenuating recurrence risk in postoperative patients with gastric cancer (GC). Kinase insert-domain receptor (KDR) gene plays an essential role in tumor growth and metastasis. This study aimed to investigate the implication of KDR genotyping on the therapeutic outcomes of patients with gastric cancer (GC) who received S-1-based adjuvant chemotherapy. A total of 169 postoperative GC with pathological staging of II and III and no metastasis who received S-1-based adjuvant chemotherapy were included retrospectively. Peripheral blood specimens were collected and prepared for KDR genotyping and KDR mRNA expression. Correlation between KDR genotype status and prognosis was performed using Kaplan-Meier survival analysis, and multivariate analysis was ultimately adopted using Cox regression analysis. Median disease-free survival (DFS) of the 169 patients with GC was 5.1 years [95% confidence interval (CI): 4.25-5.95] and median overall survival (OS) was 6.7 years (95% CI: 5.44-7.96). Rs2071559 was located at the upstream region, and the prevalence among 169 patients with GC was as follows: AA genotype in 104 cases (61.5%), AG genotype in 57 cases (33.7%), and GG genotype in 8 cases (4.7%), yielding a minor allele frequency of 0.22, which was consistent with Hardy-Weinberg equilibrium (P=0.958). Median DFS of patients with AA and AG/GG genotypes was 6.0 years and 4.0 years, respectively (P=0.002). Additionally, patients with the AA genotype had longer OS than those with the AG/GG genotype [median OS: not reached (NR) vs 5.5 years, P=0.011]. Additionally, KDR mRNA expression was significantly higher in patients with the AG/GG genotype than that in those with the AA genotype (P<0.001). Rs2071559 in KDR gene might be a promising biomarker for evaluating the recurrence risk and OS of patients with GC who received S-1-based adjuvant chemotherapy. This conclusion should be confirmed in randomized clinical trials.

Cerebellar liponeurocytoma: clinical, histopathological and molecular features of a series of three cases, including one recurrent tumor

Cerebellar liponeurocytoma (CL) is an unusual tumor, histologically composed of a mixture of small to medium-sized, rounded neurocytic cells and a variable lipomatous component. Although CL was originally considered as a subtype of medulloblastoma, subsequent molecular studies demonstrated that this tumor was a distinct entity, exhibiting the tumor protein p53 gene (TP53) missense mutations in 20% of cases, chromosome 17 deletion, and the absence of mutations in the adenomatous polyposis coli gene (APC), the protein patched homolog gene (PTCH), the kinase insert domain receptor gene (KDR), and the β-catenin gene (CTNNB). Apart from these molecular features, little is known about the pathogenesis and the genetic landscape of CL to date. In order to characterize the mutational landscape of CL and identify alterations that are driving tumorigenesis, we report a series of three cases, including one recurrent tumor, analysed by next-generation sequencing (NGS), which identified a total of 22 variants, of which four were missense mutations, nine were synonymous variants, and nine were located on intronic regions. In particular, DNA sequencing identified missense mutations in APC, KDR, and TP53 that could be implicated in promoting tumor progression and angiogenesis of CL. Furthermore, the NGS analysis revealed that recurrent CL did not have additional genetic changes compared with the primary tumor. Moreover, the high frequencies of detected mutations suggested that the identified alterations are germline variants. Indeed, an additional NGS on the genomic DNA obtained from one of the three patients confirmed the presence of the variants in the germline DNA. In conclusion, the obtained data support the hypothesis that CL is a distinct pathological entity that does not show specific somatic alterations driving tumorigenesis.

Clinical Outcomes and Safety of Apatinib Mesylate in the Treatment of Advanced Non-Squamous Non-Small Cell Lung Cancer in Patients Who Progressed After Standard Therapy and Analysis of the KDR Gene Polymorphism.

PurposeThis study investigated the clinical outcomes and safety of apatinib mesylate in the treatment of advanced non-squamous non-small cell lung cancer (NSCLC) in patients who progressed after standard therapy, and analyzed the kinase insert domain receptor (KDR) gene polymorphism.MethodsA total of 135 patients with advanced non-squamous NSCLC who received apatinib mesylate were included. Objective response rates were evaluated. Subsequently, progression-free survival (PFS) and overall survival (OS) were assessed and safety data were recorded. Additionally, peripheral blood and biopsy cancer tissue specimens were collected from the patients with NSCLC for the genotyping of the genetic polymorphism and mRNA expression of the KDR gene, respectively. Analysis on the association between genotypes and prognosis was conducted.ResultsThe objective response rate of the 135 patients with NSCLC was 18.52%, disease control rate was 65.19%, median PFS was 3.95 months, and median OS was 10.05 months. Regarding the KDR gene polymorphism analysis, the distribution of the 4397T>C polymorphism genotypes was in accordance with the Hardy–Weinberg Equilibrium (P=0.868). Moreover, the prognosis analysis indicated that the median PFS of patients with the CC/TC and TT genotypes was 2.80 and 4.80 months, respectively (P=0.002). Furthermore, the median OS of patients with the two genotypes was 9.10 and 10.56 months, respectively (P=0.041). The multivariate Cox regression analysis showed that the TC/CC genotypes were an independent factor for PFS (odds ratio: 1.72, P=0.009). There was no correlation between the polymorphism and adverse reactions. Additionally, the mRNA expression analysis suggested that the mRNA levels of KDR in cancer tissues were significantly different between the TT and TC/CC genotypes (P<0.001).ConclusionThe clinical outcomes of treatment with apatinib mesylate for advanced non-squamous NSCLC in patients who progressed after standard therapy may be influenced by the KDR 4397T>C polymorphism through mediation of the mRNA expression of KDR.

ANLN and KDR Are Jointly Prognostic of Breast Cancer Survival and Can Be Modulated for Triple Negative Breast Cancer Control.

Purpose: Kinase insert domain receptor (KDR) is the primary vascular endothelial growth factor receptor mediating survival, growth, and migration of endothelial cells and is expressed also in various tumor cells through autocrine production. The PI3K/Pten pathway is one of the downstream signalings affected by KDR activation and most commonly altered in breast cancer. Here, we investigate whether KDR expression is associated with members in PI3K/Pten signaling on the prognosis of breast cancer patients. Methods: PI3K/Pten pathway components were defined by mapping The Cancer Genome Atlas (TCGA) protein data to the KEGG database complemented by literature searching, accounting for 36 proteins subject to the interaction analysis with KDR on breast cancer patient survival. The identified interaction gene pair was subjected to in vitro validation following functional analysis. Results: Anillin (ANLN) was found to interact with KDR at translational and transcriptional levels using the public TCGA protein expression data and five gene expression datasets. Favorable prognosis corresponds to high protein but low gene expression of ANLN when KDR is highly expressed. Externally modulating cells toward low ANLN and high KDR gene expression was shown to transit triple negative cells toward a luminal-like state with increased level of ER and elevated sensitivity to Tamoxifen. Conclusion: Our study proposes a two-gene panel prognostic of breast cancer survival and a novel therapeutic strategy for triple negative breast cancer control via transiting cancer cells towards a luminal-like state sensitive to established targeted therapy.

NRP-1 and KDR polymorphisms are associated with survival time in patients with advanced gastric cancer.

Neuropilin-1 (NRP-1), a member of the NRP-family, has been reported to be vital for tumor angiogenesis, growth and metastasis. As a co-receptor of vascular endothelial growth factor (VEGF), NRP-1 can bind to VEGF and meditate vascular development through the VEGF-VEGF receptor 2 (VEGFR2) signaling pathway. Furthermore, NRP-1 is capable of binding with platelet-derived growth factor (PDGF) to regulate the PDGF-PDGF receptor (PDGR) signaling pathway in tumor angiogenesis. In the present study, The DNA was obtained from the paraffin-embedded tissues of patients with advanced gastric cancer (AGC), amplified using PCR and subsequently sequenced to determine the polymorphisms within NRP-1, VEGFR2 [kinase insert domain receptor (KDR)] and PDGF. The effect of the functional polymorphism of the aforementioned genes on the overall survival (OS) and progression-free survival (PFS) of 81 patients with advanced gastric cancer was examined. Three single nucleotide polymorphisms (SNPs) of KDR were significantly associated with clinical outcomes. The rs1870377 TT genotype was positively associated with longer OS and PFS times compared with the AA+AT genotype (PFS, P=0.012; OS, P=0.038), the rs7692791 wild-type TT genotype was positively associated with longer PFS time and the rs2034965 AA+GA genotype was associated with shorter OS time (P=0.034). With regards to the SNPs of NRP-1, the rs2065364 AA genotype was significantly associated with improved OS and PFS times (PFS, P=0.023; OS, P=0.045). Following multivariate analysis using Cox proportional hazards regression models, patients with the KDR rs7692791 TT genotype experienced a longer PFS time compared with those with the CT genotype (P=0.016), and patients with the NRP-1 rs2065364 variant-type AA genotype still experienced a longer PFS time compared with those patients with the AG+GG genotypes (P=0.006). Regarding OS, the results demonstrated that the KDR rs2034965 AG+GG genotypes presented with a significant reduction in OS time (P=0.029), and that the KDR rs1870377 AT+AA genotypes had worse OS times compared with the wild-type TT genotype (P=0.021). In addition, increased mortality risk and AGC progression were significantly associated with the number of adverse alleles for combinations of NRP-1 rs2065364 and KDR rs1870377. In conclusion, the data from the present study demonstrated that the selected KDR and NRP-1 gene polymorphisms may be potential prognostic biomarkers in AGC.

Investigation of angiogenesis genes with anterior cruciate ligament rupture risk in a South African population

ABSTRACTThe angiogenesis-signalling pathway is a physiological response after mechanical loading to promote matrix remodelling and thereby maintain tissue homeostasis. Studies have shown increased expression of angiogenic molecules in response to loading and in ruptured ligaments. Recently, polymorphisms within the vascular endothelial growth factor A (VEGFA) and kinase insert-domain receptor (KDR) genes were associated with risk of anterior cruciate ligament (ACL) ruptures and Achilles tendinopathy in Caucasian study groups. A case-control genetic association study was conducted on 100 controls and 98 participants with surgically-diagnosed ACL ruptures; of which 51 participants reported non-contact mechanism of injury (NON). All participants were genotyped for five functional polymorphisms: VEGFA (rs699947, rs1570360, rs2010963) and KDR (rs2071559, rs1870377). Haplotypes were inferred. In the male participants, the KDR rs2071559 AG genotype was significantly over-represented (P = 0.048, OR: 1.90, 95% CI: 1.00–3.59) in the controls. Furthermore, the GG genotype was significantly under-represented in the male controls compared to the male ACL group (P = 0.018, OR: 2.77, 95% CI: 1.17–6.55) and the male NON subgroup (P = 0.013, OR: 3.26, 95% CI: 1.24–8.58). Haplotype analysis implicated the KDR gene in all participants and in male participants separately. Collectively, these results implicate the angiogenesis-signalling pathway as a potentially key biological pathway contributing to ACL injury susceptibility.

Whole exome sequencing in families at high risk for Hodgkin lymphoma: identification of a predisposing mutation in the KDR gene.

Hodgkin lymphoma shows strong familial aggregation but no major susceptibility genes have been identified to date. The goal of this study was to identify high-penetrance variants using whole exome sequencing in 17 Hodgkin lymphoma prone families with three or more affected cases or obligate carriers (69 individuals), followed by targeted sequencing in an additional 48 smaller HL families (80 individuals). Alignment and variant calling were performed using standard methods. Dominantly segregating, rare, coding or potentially functional variants were further prioritized based on predicted deleteriousness, conservation, and potential importance in lymphoid malignancy pathways. We selected 23 genes for targeted sequencing. Only the p.A1065T variant in KDR (kinase insert domain receptor) also known as VEGFR2 (vascular endothelial growth factor receptor 2) was replicated in two independent Hodgkin lymphoma families. KDR is a type III receptor tyrosine kinase, the main mediator of vascular endothelial growth factor induced proliferation, survival, and migration. Its activity is associated with several diseases including lymphoma. Functional experiments have shown that p.A1065T, located in the activation loop, can promote constitutive autophosphorylation on tyrosine in the absence of vascular endothelial growth factor and that the kinase activity was abrogated after exposure to kinase inhibitors. A few other promising mutations were identified but appear to be "private". In conclusion, in the largest sequenced cohort of Hodgkin lymphoma families to date, we identified a causal mutation in the KDR gene. While independent validation is needed, this mutation may increase downstream tumor cell proliferation activity and might be a candidate for targeted therapy.

Investigation of Angiogenesis-associated Genes with Risk of Achilles Tendon Pathology

Genetic factors have been implicated with risk of Achilles tendon pathology (ATP). The angiogenesis signalling pathway plays a key role in extracellular matrix remodelling following mechanical loading. Increased levels of angiogenic cytokines and growth factors have been reported in injured Achilles tendons and after cyclic stretching of tendon fibroblasts. Vascular endothelial growth factor (VEGF) is a potent pro-angiogenic factor and the biological effects of VEGF are mediated through its receptor kinase insert-domain receptor (KDR). Recently, polymorphisms within the VEGFA and KDR genes were found to be associated with risk of anterior cruciate ligament ruptures. PURPOSE: To investigate if genes encoding proteins involved in angiogenesis-associated signalling are associated with risk of ATP in a South African and a British population. METHODS: A genetic-association study was conducted on 256 (125 SA & 130 UK) controls (CON), 194 (96 SA & 98 UK) participants with Achilles tendinopathy (TEN) and 80 (45 SA & 35 UK) participants with partial or complete ruptures of the Achilles tendon (RUP). All participants were genotyped for the functional VEGFA rs699947, VEGFA rs1570360, VEGFA rs2010963, KDR rs2071559 and KDR rs1870377 polymorphisms. Haplotypes were also inferred for VEGFA and KDR. Statistical analyses were conducted to determine any significant differences (p<0.05) between the groups (CON vs. TEN and CON vs. RUP). RESULTS: No independent significant differences were observed in the genotype frequency distributions of any of the polymorphisms between the CON vs. TEN or the CON vs. RUP groups for either population although there were trends towards significance. When the SA and UK groups were combined, the VEGFA rs699947 genotype frequency distribution was significantly different (p=0.017) between the male CON and male RUP groups, with the CA genotype significantly over-represented in the RUP group (p=0.006, OR: 2.6; 95% CI: 1.3-5.1). Inferred haplotype analyses showed the VEGFA A-A-G haplotype was significantly over-represented (p=0.023) in the UK CON group (37%) compared to the UK TEN group (28%). CONCLUSIONS: These novel findings provide preliminary evidence highlighting the potential biological significance of the angiogenesis signalling pathway in the aetiology of acute musculoskeletal injuries. Supported by the NRF, URC and MRC.

Effects of kinase insert domain receptor (KDR) gene silencing on the sensitivity of A549 cells to erlotinib.

We investigated the effects of kinase insert domain receptor (KDR) gene silencing on the proliferation of A549 cells and their sensitivity to erlotinib. A KDR small interfering RNA (siRNA) sequence was designed and synthesized; then, it was transfected into A549 cells using Lipofectamine(TM) 2000. KDR mRNA and protein expression after KDR gene silencing was detected by reverse transcription polymerase chain reaction and western blotting; the A549 cell cycle was detected by flow cytometry. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and colony formation assay were performed to determine the sensitivity of A549 cells to erlotinib after KDR gene silencing. After 48h of KDR gene silencing, there was a significant decrease in KDR gene and protein expression (P < 0.05). The A549 cell cycle was arrested at the G0/G1 phase, and the number of cells in the S phase decreased; the difference was statistically significant (P < 0.05). In the KDR gene silencing group, the sensitivity of A549 cells to erlotinib was significantly enhanced (P < 0.05). KDR siRNA can significantly silence the KDR gene in A549 cells, inhibit the proliferation of A549 cells, and enhance their sensitivity to erlotinib.

The relationship of kinase insert domain receptor gene polymorphisms and clinical outcome in advanced hepatocellular carcinoma patients treated with sorafenib.

Kinase insert domain receptor (KDR) is the principal receptor that promotes the pro-angiogenic action of vascular endothelial growth factor and has been the principal target of anti-angiogenic therapies. Our aim was to determine whether single-nucleotide polymorphisms (SNPs) in KDR gene are associated with clinical outcomes after first-line sorafenib therapy in advanced hepatocellular carcinoma (HCC). The SNPs in KDR were tested in 78 advanced HCC patients receiving first-line sorafenib. Correlations with clinicopathological features and survival were analyzed. Patients with AA genotype of rs1870377 and AA genotype of rs2305948 were significantly associated with a better response and longer time to progression (TTP) (5.8 vs 4.0 months, P=0.001; 5.8 vs 4.5 months, P=0.016, respectively). Patients harboring AA genotype in rs1870377 and TT/TC genotype in rs2071559 had a longer overall survival (OS) (15.0 vs 9.6 months, P=0.001; 13.0 vs 9.0 months, P=0.007, respectively). At multivariate analysis, major vascular invasion and rs1870377 were independent factors in TTP and performance status, rs1870377, and rs2071559 were independent factors in OS. Our results suggest that SNPs in KDR gene can predict clinical outcome in advanced HCC patients receiving first-line sorafenib.

Genetic variants in the KDR gene is associated with the prognosis of transarterial chemoembolization treated hepatocellular carcinoma.

Kinase insert domain receptor (KDR) is the principal receptor that promotes the proangiogenic action of vascular endothelial growth factor and is involved in the tumorigenesis and progression of many malignancies, including hepatocellular carcinoma (HCC). Single-nucleotide polymorphisms (SNPs) of KDR have been reported to be with the risk and prognosis of several malignancies. Our aim was to determine whether SNPs in KDR gene are associated with clinical outcomes in HCC patients treated with transcatheter arterial chemoembolization. A total of 192 HCC patients were tested for KDR SNPs, and the SNP results were correlated with progression-free survival (PFS) and overall survival (OS). The association of the SNPs with the overall survival (OS) of patients was assessed by Kaplan-Meier method, and then Cox proportional hazards model was used to assess the variables resulted significant at univariate analysis. No significant differences were found in correlation between KDR SNPs and patients' PFS. Our data showed that genotype AA+TA of rs1870377 and genotype CC+TC of rs2071559 were significantly associated with overall survival of HCC patients (P<0.001 and P<0.001, respectively) and remained as significant predictors for OS adjusting for high level of serum AFP (>400 μg/L), existence of portal vein tumor thrombus, and high BCLC stage (HR=0.61; 95% CI, 0.36-0.88; P=0.003 and HR=0.54; 95% CI, 0.40-0.94; P=0.002, respectively). Our results suggest that SNPs rs1870377 and rs2071559 in the KDR gene may serve as independent prognosis biomarkers for unresectable HCC patient, which warranted further validating investigation.

The association of genes involved in the angiogenesis-associated signaling pathway with risk of anterior cruciate ligament rupture.

Angiogenesis-associated signaling is a fundamental component in the remodeling of the extracellular matrix in response to loading. Genes encoding protein components within this signaling cascade are therefore suitable candidates for investigation into ACL injury susceptibility: namely, vascular endothelial growth factor A isoform (VEGFA), kinase insert-domain receptor (KDR), nerve growth factor (NGF), and hypoxia inducible factor-1α (HIF1A). A case-control genetic association study was conducted on 227 asymptomatic control participants and 227 participants with surgically diagnosed ACL ruptures of which 126 participants reported a non-contact mechanism of rupture. All participants were genotyped for seven polymorphisms within the four genes. The VEGFA rs699947 CC genotype (p=0.010, OR: 1.92, 95% CI: 1.17-3.17) was significantly over-represented within participants with non-contact ACL ruptures. The VEGFA rs1570360 GA genotype was significantly over-represented in the CON group (p=0.007, OR: 1.70, 95% CI: 1.16-2.50). Furthermore, the KDR rs2071559 GA genotype was significantly over-represented in the female controls (p=0.023, OR: 2.16, 95% CI: 1.11-4.22). Inferred haplotype analyses also implicated genomic regions spanning the VEGFA and KDR genes. These novel findings suggest that regions within VEGFA and KDR may be implicated in the pathophysiology of ACL ruptures; highlighting the potential biological significance of angiogenesis-associated signaling in the aetiology of ACL ruptures.

Genetic variants in KDR transcriptional regulatory region affect promoter activity and intramuscular fat deposition in Erhualian pigs

Kinase insert domain receptor (KDR), a vascular endothelial growth factor (VEGF) receptor, is widely regarded as having a principal role in mediating VEGF-induced responses in angiogenesis. As angiogenesis provides oxygen and nutrients for growth and deposition of adipose cells, our objective was to determine whether the promoter polymorphisms in the KDR gene have effects on intramuscular fat (IMF) deposition in the longissimus dorsi muscle. Three novel SNPs, c.-1316A>G, c.-1303C>T and c.-1108A>C, were revealed to have differential allele distribution between high- and low-IMF content groups by comparative sequencing of DNA pools. The three SNPs were completely linked, forming only ACA or GTC haplotypes when genotyped in 105 Erhualian purebred pigs and 98 Duroc × Large White × Yorkshire (D×L×Y) cross-bred pigs. It is interesting that the ACA haplotype is present exclusively in Erhualian pigs and not in D×L×Y pigs. The ACA promoter was found to have higher activity than GTC type for KDR transcription using either gene expression analysis or luciferase assay. Site-direct mutation analysis demonstrated that c.-1316A>G is the causation of promoter activity alteration. Furthermore, we detected that CD31 (also known as PECAM1) and CD34, two blood vessel endothelial markers, expressed higher in ACA/ACA individuals. We concluded that the ACA promoter might be a desirable form for improving IMF content by promoting higher KDR gene expression and more blood vessel network.

Single-Nucleotide Polymorphisms in the KDR Gene in Pregnancies Complicated by Gestational Hypertensive Disorders and Small-for-Gestational-Age Infants

Pregnancies complicated by preeclampsia and small-for-gestational-age (SGA) infants share placental vascular abnormalities and both disorders confer increased risk of later life coronary artery disease. Kinase insert domain receptor (KDR) is the main receptor for vascular endothelial growth factor A, a potent angiogenic factor which regulates the development of the placental vasculature. Two polymorphisms in KDR (-604T/C and Val297Ile) are known to be associated with coronary artery disease. We investigated the association of these polymorphisms with preeclampsia, gestational hypertension, and SGA infants. Nulliparous pregnant women, their partners, and infants were recruited to a prospective cohort study (n = 1169). Doppler ultrasound of the uterine and umbilical arteries was performed at 20 weeks of gestation. Preeclampsia, gestational hypertension, and SGA were defined according to international guidelines. DNA extracted from peripheral venous or cord blood was genotyped using the Sequenom MassARRAY system. Multivariable logistic regression was used to compare the odds for the pregnancy complications between the genotype groups adjusting for potential confounders. Among 937 Caucasian pregnancies, 427 (45.6%) were uncomplicated, 75 (8.0%) developed preeclampsia, 102 (10.9%) developed gestational hypertension, and 72 (7.7%) had SGA infants in the absence of maternal hypertensive disease. Paternal and neonatal KDR-604T/C was associated with preeclampsia (adjusted odds ratio [aOR] 1.6, 95% confidence interval [CI] 1.0-3.0 and aOR 2.2, 95% CI 1.0-4.4), SGA (aOR 1.9, 95% CI 1.1-3.3 and aOR 2.2, 95% CI 1.2-3.9), and SGA with abnormal Doppler (aOR 2.7, 95% CI 1.2-5.9 and aOR 3.2, 95% CI 1.2-5.9). Paternal and neonatal carriage of the KDR-604T/C polymorphism is associated with the risk of preeclampsia and SGA infants.

Potentially functional genetic variants in KDR gene as prognostic markers in patients with resected colorectal cancer

Angiogenesis plays a key role in the development and treatment response of various tumors. The signaling transductions mediated by the binding of vascular endothelial growth factor (VEGF) to its receptor KDR (kinase insert domain receptor) is the most important pathway in tumor angiogenesis. Single nucleotide polymorphisms (SNPs) in VEGF have been extensively implicated in the etiology and treatment outcome of colorectal cancer (CRC). However, no study has been reported evaluating the role of KDR SNPs in CRC prognosis. We herein assessed the association between four potentially functional KDR SNPs and tumor recurrence in a Chinese population with 408 surgically resected CRC patients. The most significant SNP was for rs10013228 located in the KDR gene promoter. Compared with the homozygous wild-type genotype, the variant-containing genotypes of this SNP were significantly associated with a reduced recurrence risk with a hazard ratio (HR) of 0.53 (95% confidence interval [CI] 0.30-0.95, P = 0.032). Moreover, a borderline significant association was noted for another promoter SNP, rs2071559, with an HR of 0.67 (95% CI 0.42-1.07, P = 0.092). In stratified analysis, the associations of both SNPs were more prominent in patients receiving chemotherapy (HR = 0.47, 95% CI 0.23-0.94, P = 0.033 for rs10013228 and HR = 0.55, 95% CI 0.32-0.95, P = 0.032 for rs2071559). Further analysis revealed a protective effect on patient recurrence by chemotherapy (HR = 0.56, 95% CI 0.32-1.01, P = 0.046), which was more evident in patients with the variant-containing genotypes of each of the two SNPs (HR = 0.09, 95% CI 0.02-0.55, P = 0.009 for rs10013228 and HR = 0.39, 95% CI 0.18-0.86, P = 0.020 for rs2071559). Collectively, our findings suggest SNPs in the KDR gene modulate CRC recurrence, especially in those receiving chemotherapy.

Association of polymorphisms/haplotypes of the genes encoding vascular endothelial growth factor and its KDR receptor with recurrent pregnancy loss

BACKGROUND Vascular endothelial growth factor (VEGF) and its kinase insert domain receptor (KDR) play an important role in angiogenesis, and their gene expression patterns also suggest a close relationship with early pregnancy. However, limited information is available regarding the role of the VEGF system, especially its KDR receptor, in recurrent pregnancy loss (RPL). This study was conducted to investigate a genetic association between VEGF and its receptor gene (KDR) with idiopathic RPL. METHODS In this case-control study, 115 women who had experienced at least two consecutive spontaneous miscarriages (n= 62 women with two miscarriages, n= 53 with three or more) and 170 controls were included. A total of 14 tag single-nucleotide polymorphisms (SNPs) of VEGF and KDR were selected from the HapMap Web site and three functional SNPs [rs1570360 (-1154G/A) of VEGF; rs2305948 (V297I) and rs1870377 (Q472H) of the KDR gene] were genotyped using primer extension analysis. We further used multifactor dimensionality reduction analysis to evaluate gene-gene interactions. RESULTS One tag SNP (rs6838752) and the functional SNP (Q472H) of the KDR gene were in complete linkage and showed significant differences between patients and controls (P< 0.05). The frequencies of haplotypes of VEGF (A-T-G haplotype) and KDR (A-C-A-T-G haplotype) showed significant differences in patients versus controls (P< 0.05). All comparisons with controls remained significant when the subgroup of women with three or more miscarriages was analyzed. CONCLUSIONS VEGF and its receptor gene (KDR) are associated with idiopathic RPL. The VEGF/KDR system jointly contributes to recurrent miscarriage in Taiwanese Han women.

Gene Response in Endothelial Cells Cultured on Engineered Surfaces Is Regulated by Shear Stress

In vitro endothelialization of small-diameter synthetic vascular prostheses confluently lined with cultured autologous endothelial cells (ECs) before implantation has been shown to increase their patency. Many authors have studied the effects of shear stress on EC gene response seeded on various substrates showing different gene expression profiles according to cell type, flow times, or shear type with different molecular biology techniques, but few studies have reported any EC gene response to shear stress when cells are seeded on vascular grafts. The purpose of this in vitro study was to investigate whether ECs were able to transduce shear stress at the level of the nucleus. Human saphenous vein ECs were seeded on glass slides coated with gelatin or fibrin glue or on 6-mm fibrin-glue-coated grafts. Then cells were exposed to 12 dyn/cm(2) for 4 h and ribonucleic acid (RNA) were extracted. The relative messenger RNA (mRNA) expression was studied using real-time quantitative polymerase chain reaction for the following mRNAs: von Willebrand Factor, tissue-plasminogen activator, CD31, vascular endothelial (VE)-cadherin, beta(1) integrin, and vascular endothelial growth factor receptor type 2. From parallel flow chambers, results have shown similar EC gene response on gelatin and fibrin glue under laminar shear stress with downregulation of prothrombotic genes, as well as upregulation of nonthrombotic genes and upregulation of adhesion molecules such as VE-cadherin, but some discrepancies are noted, with a downregulation of CD31 and kinase insert domain receptor (KDR) for the former, without significant variation for the latter. In comparison, results show upregulation of tissue type plasminogen activator gene and downregulation of KDR, VE-cadherin, and beta(1) integrin genes in ECs lining grafts. To conclude, the major finding of our study is to show that human saphenous vein ECs seeded on fibrin glue (in planar flow chambers or in tubular grafts) can be regulated using shear stress via gene expression changes in a nonthrombotic way.

The kinase insert domain receptor gene (KDR) has been relocated to chromosome 4q11-->q12.

Through in situ hybridization of a genomic DNA probe to metaphase chromosomes, we have localized the KDR gene to 4q11-->q12. This is the same locus as that for two other receptor tyrosine kinases, PDGFRA and KIT. This location for KDR differs from that which we previously reported using a cDNA probe. Using cDNA probes for both KDR and KIT identifies a locus at 4q31-->q32 which may uncover another cluster of receptor tyrosine kinase genes.

The KDR gene maps to human chromosome 4q31.2----q32, a locus which is distinct from locations for other type III growth factor receptor tyrosine kinases.

KDR (kinase insert domain receptor), a new type III receptor tyrosine kinase gene, maps to human chromosome 4q31.2----q32 by fluorescence in situ hybridization. This differs from the chromosomal locations of other members of this gene family.