EGFR somatic doublets in lung cancer are frequent and generally arise from a pair of driver mutations uncommonly seen as singlet mutations: one-third of doublets occur at five pairs of amino acids

Doublet mutations in cancer are not well studied. We find that allelic somatic doublet mutations are present at high frequency in the epidermal growth factor receptor (EGFR) tyrosine kinase (TK) domain in lung cancers. When doublets from the literature are added, a total of 96 doublets are available for analysis. The frequency of doublets overall is 6%, which is sevenfold greater than that observed in normal tissue in mouse. All characterized doublets are allelic, and silent mutations occur rarely. About half of all doublets contain one or two of 12 distinct missense mutations at five amino acids: E709, G719, S768, T790 and L861. The mutations at these five amino acids are seldom reported as singlets. Moreover, when the common L858 target is included, more than one-third of EGFR doublets are one of five specific missense pairs: G719/E709, G719/S768, G719/L861, L858/E709 and L858/T790. Structure suggests function: The data imply that most EGFR doublets are NOT consistent with a 'driver and passenger' mutation mechanism. EGFR doublets are highly skewed relative to singlets, consistent with functional selection of two individually suboptimal mutations that, in combination, have enhanced oncogenic potential.

Blood pressure and risk of cardiovascular disease in Chinese men and women

BACKGROUND

We examined the relationship between systolic and diastolic blood pressure (BP) and the incidence of cardiovascular disease (CVD) in a nationally representative cohort of 169,871 men and women > or = 40 years of age in China.

METHODS

Data on BP and other variables were obtained at a baseline examination in 1991 using standard protocols. Follow-up evaluation was conducted in 1999-2000, with a response rate of 93.4%.

RESULTS

After adjustment for age, sex, cigarette smoking, alcohol consumption, physical activity, body mass index, education, geographic region, urbanization, and time-dependent history of diabetes, a strong and linear association between both systolic and diastolic BP and incidence of CVD, coronary heart disease and stroke were observed (all P < 0.0001). For example, the relative risks (95% confidence interval (CI)) of CVD incidence were 1.09 (1.00-1.18), 1.25 (1.16-1.35), 1.49 (1.38-1.62), 2.15 (1.99-2.31), 3.01 (2.78-3.27), and 4.16 (3.84-4.51) for those with systolic/diastolic BP of 110-119/75-79, 120-129/80-84, 130-139/85-89, 140-159/90-99, 160-179/100-109, and > or = 180/110 mm Hg compared to those with BP <110/75 mm Hg. Increases in systolic BP were associated with a greater risk of CVD compared to corresponding increases in diastolic BP. The linear trend for increased CVD risk being related to higher BP levels was observed in all subgroups of gender, age, body weight, and cigarette smoking.

CONCLUSIONS

Our results indicate that there is a strong, linear, and independent relationship between BP levels and the risk of CVD in Chinese adults. Systolic BP is a stronger predictor of CVD risk compared to diastolic BP.

Hypertension and cardiovascular diseases intervention in the capital steel and iron company and Beijing Fangshan community

Two intervention studies are described involving >110,000 subjects in each. The first was in a steel factory where one intervention site had health promotion, aimed at altering diet, and particularly reducing salt and fat intake, modest alcohol drinking and smoking cessation, together with a high-risk strategy of hypertension control. The second study involved similar population and high-risk strategies in three of five rural communities. Significant reductions occurred in both intervention and control factory sites in blood pressure, with greater falls in the intervention site, together with a marked additional reduction in salt intake and better control of hypertension. In the rural communities, blood pressure fell in all communities to a more modest degree than in the factory, but with greater blood pressure falls, together with greater smoking cessation and more modest alcohol drinking in the intervention compared with the control communities. Stroke mortality fell by 74.3% and all strokes morbidity by 54.7% in the steel factory as a whole. In the rural communities, the intervention sites showed significantly greater falls in stroke rates than in the control communities. These data show the value and effectiveness of combining a population and high-risk strategy for controlling blood pressure and cardiovascular diseases in both a rural setting and in the work place in China.

Alcohol consumption and the risk of end-stage renal disease among Chinese men

We examined the relationship between alcohol consumption and incidence of end-stage renal disease (ESRD) in a prospective cohort of 65 601 Chinese men aged 40 years and older. Information on the amount and type of alcohol consumed was collected at a baseline examination with follow-up evaluations conducted 8-9 years later. During the 500 876 person-years of follow-up, 176 participants initiated renal replacement therapy or died from renal failure. Compared to non-drinkers, the relative risk of ESRD was 0.67 among men consuming less than 21 drinks per week and 0.52 among men consuming this amount or more after adjustment for age, geographic region, urbanization, education, body mass index, physical activity, and cigarette smoking. The inverse association between alcohol consumption and ESRD existed even after adjustment for systolic blood pressure, and history of diabetes and cardiovascular disease. Our results suggest an inverse relationship between alcohol consumption and risk of ESRD in Chinese men. Heavy alcohol consumption, however, may lead to increased risk of morbidity and mortality from other causes; therefore, the implications from these findings should be interpreted cautiously.

Cardiovascular risk prediction tools for populations in Asia

BACKGROUND

Cardiovascular risk equations are traditionally derived from the Framingham Study. The accuracy of this approach in Asian populations, where resources for risk factor measurement may be limited, is unclear.

OBJECTIVE

To compare "low-information" equations (derived using only age, systolic blood pressure, total cholesterol and smoking status) derived from the Framingham Study with those derived from the Asian cohorts, on the accuracy of cardiovascular risk prediction.

DESIGN

Separate equations to predict the 8-year risk of a cardiovascular event were derived from Asian and Framingham cohorts. The performance of these equations, and a subsequently "recalibrated" Framingham equation, were evaluated among participants from independent Chinese cohorts.

SETTING

Six cohort studies from Japan, Korea and Singapore (Asian cohorts); six cohort studies from China; the Framingham Study from the US.

PARTICIPANTS

172,077 participants from the Asian cohorts; 25,682 participants from Chinese cohorts and 6053 participants from the Framingham Study.

MAIN RESULTS

In the Chinese cohorts, 542 cardiovascular events occurred during 8 years of follow-up. Both the Asian cohorts and the Framingham equations discriminated cardiovascular risk well in the Chinese cohorts; the area under the receiver-operator characteristic curve was at least 0.75 for men and women. However, the Framingham risk equation systematically overestimated risk in the Chinese cohorts by an average of 276% among men and 102% among women. The corresponding average overestimation using the Asian cohorts equation was 11% and 10%, respectively. Recalibrating the Framingham risk equation using cardiovascular disease incidence from the non-Chinese Asian cohorts led to an overestimation of risk by an average of 4% in women and underestimation of risk by an average of 2% in men.

INTERPRETATION

A low-information Framingham cardiovascular risk prediction tool, which, when recalibrated with contemporary data, is likely to estimate future cardiovascular risk with similar accuracy in Asian populations as tools developed from data on local cohorts.

Association analysis of the variant in the regulatory subunit of phosphoinositide 3-kinase (p85alpha) with Type 2 diabetes mellitus and hypertension in the Chinese Han population

AIMS

To determine whether variants in the gene for the regulatory subunit of phosphoinositide 3-kinase (p85alpha) are associated with Type 2 diabetes mellitus (Type 2 DM) and hypertension in a Chinese population.

METHODS

We performed a case-control study genotyping the Met326Ile and IVS4+82A>G polymorphisms in 494 patients with Type 2 DM and hypertension and 557 normal controls from the north of China. Individual genotypes were identified by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The IVS4+82A>G polymorphism was further confirmed by direct sequencing in 20 randomly selected cases.

RESULTS

The IVS4+82A>G polymorphism that is common in Caucasians was not detected in our population. Frequencies of genotypes and alleles of Met326Ile polymorphism were not significantly different between cases and controls in whole samples by univariate analysis. Logistic regression analysis demonstrated that Ile326Ile genotype was associated with a 2.085-fold (95% CI, 1.043-4.168, P = 0.0377) relative risk of diabetes and hypertension. After stratification by obesity, the frequency of Ile326Ile genotype in cases was higher than that in controls (18/304 vs. 13/510, P = 0.015) among non-obese individuals (BMI < 28 kg/m2). We did not find that this missense mutation was associated with blood pressure, glucose and blood lipids in the control group.

CONCLUSION

Our data indicate that the Met326Ile variation in the gene encoding the p85alpha protein might contribute to the increased risk of Type 2 DM and hypertension in Chinese.

beta2-Adrenergic receptor gene variations associated with stage-2 hypertension in northern Han Chinese

The aim of this study was to investigate the association between polymorphisms in the beta(2)-adrenergic receptor gene (ADRB2) (-47C/T, Arg16/Gly, Gln27/Glu) and stage-2 hypertension in northern Han Chinese. We recruited 503 individuals with stage-2 hypertension and 504 age-, gender-, and area-matched controls from the International Collaborative Study of Cardiovascular Disease in Asia. Genotyping was performed using PCR-RFLP. Logistic regression analyses revealed that carriers of the Gly16 allele had a significantly higher odds ratio (OR) for hypertension, while carriers of the Glu27 allele had a significantly lower OR. In multivariate linear regression analyses, the Arg16/Gly and Gln27/Glu genotypes were significantly associated with systolic blood pressure level (p = 0.004 and p < 0.001, respectively). In haplotype analyses, we found the frequency of haplotypes composed of the Gly16 and Gln27 alleles was significantly higher, whereas the frequency of haplotypes composed of the Arg16 and Glu27 alleles was significantly lower, in hypertensives compared to their controls (both p = 0.001). These results indicate that the Gly16 and Gln27 alleles of the ADRB2 gene confer an increased risk for stage-2 hypertension in this northern Han Chinese population.

Linkage analysis of chromosome 1 with essential hypertension and blood pressure quantitative traits in Chinese families

Summary Several recent studies have linked human chromosome 1p to essential hypertension (EH) or blood pressure (BP) levels. In an independent population of 148 hypertensive families from China we tested these findings. Thirty highly informative microsatellite markers spanning about 284 cM were genotyped. Qualitative linkage analysis was conducted using non-parametric linkage analysis implemented within the GENEHUNTER 2.0 software, whereas quantitative analysis was performed with the variance-component method integrated in the S.O.L.A.R. 1.7.4. software with an additional Haseman-Elston method using the SAGE/SIBPAL2 program. We observed suggestive linkage between D1S2890 (1p31, 80.9 cM) and hypertension using the multipoint non-parametric linkage analysis (NPL = 2.19, P = 0.01). In the quantitative analysis we didn't observe a significant excess of identity-by-descent allele sharing between the systolic blood pressure levels and the markers. However, the D1S207 microsatellite marker (1p21) which is located about 107 cM from the telomere of 1p showed weak linkage evidence with the diastolic blood pressure levels (LOD = 1.42). These findings suggest linkage of 1p31 with essential hypertension in the ethnic Chinese, and provide a potential clue for future studies involving candidate genes for hypertension.

Smoking, quitting, and the risk of cardiovascular disease among women and men in the Asia-Pacific region

BACKGROUND

Although smoking is a major risk factor for cardiovascular disease, it has been suggested that Asians may be less susceptible to the adverse effects of smoking than Caucasians. This may have contributed to the high prevalence of smoking, and the low quitting rates, in Asian men. Worldwide, smoking rates are increasing for women, amongst whom cardiovascular awareness is relatively poor.

METHODS

An individual participant data analysis of 40 cohort studies was carried out, involving 463 674 Asians (33% female) and 98 664 Australasians (45% female). Cox proportional hazard models, stratified by study and sex where appropriate, were employed.

RESULTS

The HR [95% confidence interval (CI)], comparing current smokers with non-smokers, for coronary heart disease (CHD) was 1.60 (1.49-1.72); haemorrhagic stroke 1.19 (1.06-1.33); ischaemic stroke 1.38 (1.24-1.54). There was a clear dose-response relationship between the number of cigarettes smoked per day and both CHD and stroke, with no significant difference (P >/= 0.20) between populations from Asia and Australia/New Zealand. Although there was no sex difference for stroke in the effect of amount smoked (P = 0.16), for CHD, women tended to have higher hazard ratios than men (P = 0.011). Quitting gave a clear benefit, which was not significantly different between the sexes or regions (P > 0.63). The HR (CI) for ex-smokers compared with current smokers was 0.71 (0.64-0.78) for CHD and 0.84 (0.76-0.92) for stroke.

CONCLUSIONS

Unless urgent public health measures are put into place, the impact of the smoking epidemic in Asia, and among women, will be enormous. Tobacco control policies that specifically target these populations are essential.

A Comparison of Lipid Variables as Predictors of Cardiovascular Disease in the Asia Pacific Region

PURPOSE

Many guidelines advocate measurement of total or low density lipoprotein cholesterol (LDL), high density lipoprotein cholesterol (HDL), and triglycerides (TG) to determine treatment recommendations for preventing coronary heart disease (CHD) and cardiovascular disease (CVD). This analysis is a comparison of lipid variables as predictors of cardiovascular disease.

METHODS

Hazard ratios for coronary and cardiovascular deaths by fourths of total cholesterol (TC), LDL, HDL, TG, non-HDL, TC/HDL, and TG/HDL values, and for a one standard deviation change in these variables, were derived in an individual participant data meta-analysis of 32 cohort studies conducted in the Asia-Pacific region. The predictive value of each lipid variable was assessed using the likelihood ratio statistic.

RESULTS

Adjusting for confounders and regression dilution, each lipid variable had a positive (negative for HDL) log-linear association with fatal CHD and CVD. Individuals in the highest fourth of each lipid variable had approximately twice the risk of CHD compared with those with lowest levels. TG and HDL were each better predictors of CHD and CVD risk compared with TC alone, with test statistics similar to TC/HDL and TG/HDL ratios. Calculated LDL was a relatively poor predictor.

CONCLUSIONS

While LDL reduction remains the main target of intervention for lipid-lowering, these data support the potential use of TG or lipid ratios for CHD risk prediction.

Haplotypic analyses of the aldosterone synthase gene CYP11B2 associated with stage-2 hypertension in northern Han Chinese

The objective of this study was to investigate the association of polymorphisms in the aldosterone synthase gene CYP11B2 (-344T/C, Lys173/Arg, and an intronic conversion [IC]) with stage-2 hypertension in northern Han Chinese. A total of 503 hypertensives and their age-, gender-, and area-matched controls were included in this study. The female hypertensives had significantly higher frequencies of the -344T, 173Lys, and IC-conversion alleles (p = 0.002, 0.002, and 0.014, respectively). The estimated frequency of haplotype composed of the -344T, 173Lys, and IC-conversion alleles (haplotype 4) was significantly higher in the female hypertensives compared with their controls (p = 0.007). Using a multivariate score test, we found that haplotype 4 remained associated with female hypertension after the adjustment for covariates (p = 0.003), while the haplotype 3 of T-Arg-WT showed a protective effect both in the males and in the females (p = 0.03 and 0.006, respectively). The odds ratio for haplotype phase of 4-4 was 2.60 (95% CI, 1.21-5.58) and for 3-3, 0.20 (95% CI, 0.03-0.77). These results indicate that the Lys173 and the IC-conversion allele of the CYP11B2 gene confer an increased risk for stage-2 hypertension in northern Han Chinese women.

Prevalence of diabetes and impaired fasting glucose in the Chinese adult population: International Collaborative Study of Cardiovascular Disease in Asia (InterASIA)

AIMS/HYPOTHESIS

To estimate the prevalence of diagnosed and undiagnosed diabetes and impaired fasting glucose in the general adult population of China.

METHODS

The International Collaborative Study of Cardiovascular Disease in ASIA, conducted from 2000 to 2001, included a nationally representative sample of 15 540 adults, aged 35 to 74 years. An overnight fasting blood specimen was collected to measure serum glucose and information on history of diabetes and use of hypoglycaemic medications was obtained by a standard questionnaire. Undiagnosed diabetes (fasting glucose > or =7.0 mmol/l) and impaired fasting glucose (6.1-6.9 mmol/l) were defined using the American Diabetes Association criteria.

RESULTS

Prevalence of self-reported diagnosed diabetes, undiagnosed diabetes, and impaired fasting glucose in Chinese adults were 1.3%, 4.2%, and 7.3%, respectively. Overall, 5.2% or 12.7 million men and 5.8% or 13.3 million women in China aged 35 to 74 years had diabetes (self-reported diagnosis plus undiagnosed diabetes). The age-standardized prevalence of diabetes was higher in residents of northern compared to southern China (7.4% vs 5.4%, p<0.001) and in those living in urban compared to rural areas (7.8% vs 5.1%, p<0.001).

CONCLUSIONS/INTERPRETATION

Our results show that the prevalence of diabetes in the adult population in China is much higher than previously reported. Three out of every four diabetes patients are undiagnosed, indicative of a lack of population-based screening programmmes and a relatively rapid and recent increase in incidence of diabetes. These results indicate that diabetes has become a major public health problem in China and underscore the need for national strategies aimed at prevention and treatment of diabetes.

[The development and application of computer-aided bone histomorphometry system]

The aim of this study is to develop a Computer-aided Bone Histomorphometry System. The method is based on the Micro-graphical Digital System composed of microscope, digital camera, computer and related programs. The methodology was developed to measure the basic data on each image of visual field of hard bone tissue with computer-assistance. Following this, the parameters of bone volume, bone structure and bone metabolism were calculated based on the standardization of bone histomorphometry. Such method has been used in the experimental and clinical studies of osteoporosis to predict the fracture risk and evaluate the drug effect.

[Evaluation on the effect of cardiovascular prevention program in Fangshan, Beijing]

OBJECTIVE

To evaluate the effect of cardiovascular prevention program in Fangshan, Beijing (BFCP) from 1991-1999.

METHODS

BFCP was a comprehensive community trial covering 120,000 residents in five communities, including three as intervention communities (IC), and two as control communities (CC), in Fangshan, suburb of Beijing. The program was implemented under both population and high risk individual strategies, focusing on health education and hypertension control. The main intervention measures were as follows: (1) network setup; (2) health education and promotion; (3) health professional training; (4) detection and management of hypertensive patients.

RESULTS

Baseline, midterm and final cross-sectional surveys were conducted in the year 1991, 1995 and 1999, respectively. After 9-year intervention, improvement was found in population of IC versus CC (P < 0.01 or P < 0.05) for knowledge, attitude and behavior of CVD prevention, awareness on hypertension, treatment and control rates, as well as the quantity of dietary intake of protein, potassium and calcium. Risk factors such as systolic blood pressure, diastolic blood pressure, rates of smoking and alcohol drinking declined in the population in IC versus CC (P < 0.01). The average morbidity and mortality of stroke were 18.7% (u = 2.81, P < 0.01) and 17.7% (u = 2.91, P < 0.01), significantly lower in the IC versus CC. No significant difference was identified on the morbidity and mortality of coronary heart diseases between IC and CC.

CONCLUSION

The comprehensive community prevention approach was feasible and effective in the prevention and control of cardiovascular diseases in rural populations in China.

[Job strain and hypertension risk in Capital Steel and Iron Company in Beijing]

OBJECTIVE

To assess the relation between the scales of Job Demand control Model (or "Job strain") and the prevalence of hypertension.

METHODS

A standardized questionnaire base-line survey was conducted among 1,556 male and female employees aged 18-65 in two factories of the Capital Steel and Iron Company, Beijing, in 1997 to investigate the socio-demographic factors and job strain so as to identify the major risks of hypertension.

RESULTS

The prevalence of hypertension increased from 6.5% to 21.2% with an age-adjusted relative prevalence ratio (95% CI) of 3.26 (2.30, 4.41) when the job strain pattern changed from high control and low demand to moderate control and moderate demand and further to low control and high demand among the male employees. After adjustment for confounding effects from age, education, body mass index, smoking, alcohol consumption, and physical activity, the odds ratio (95% CI) was attenuated to 2.31 (1.45, 3.81). Such a phenomenon was not typical among females.

CONCLUSION

The risk of hypertension was elevated with the increase of job strain in men.

Determination of active component in silymarin by RP-LC and LC/MS

Silybin, isosilybin, silydianin and silycristin in silymarin were separated and quantitatively determined by RP-HPLC. Two diastereoisomers of silybin and isosilybin were respectively separated by RP-HPLC and confirmed by LC/MS. Chromatographic condition consisted of column: Shim-pack VP-ODS (150 x 4.6mm i.d. 5 microm) and Pre-column (10 x 4.6 mm i.d. 5 microm); mobile phase: methanol and solvent mixture (water: dioxane=9:1) by gradient; flow rate: 1.5ml/min; column temp.: 40 degrees C; detector wavelength: 288 nm; The recovery of 99.66% for silycristin, 99.48% for silydianin, 100.0% for silybin and 98.72% for isosilybin was respectively obtained.

Effect of potassium supplementation on blood pressure in Chinese: a randomized, placebo-controlled trial

OBJECTIVE

To examine the effect of potassium supplementation on blood pressure (BP) in a Chinese population who consume a habitual high sodium and low potassium diet.

DESIGN

Randomized, double-blind, placebo-controlled trial.

SETTING

Community sample from Beijing, China.

PARTICIPANTS

A total of 150 men and women aged 35-64 years with an initial systolic BP 130-159 mmHg and/or diastolic BP 80-94 mmHg.

INTERVENTIONS

Participants were randomly assigned to take 60 mmol potassium chloride supplement or placebo for 12 weeks.

MAIN OUTCOME MEASURE(S)

BP measurements were obtained at baseline, and at 6 weeks and 12 weeks during the trial, using random-zero sphygmomanometers.

RESULTS

The average baseline urinary excretion of sodium and potassium was 182 mmol/24 h and 36 mmol/24 h. Baseline BP and other measured variables were similar between the potassium supplementation and placebo groups. In the active compared to the placebo treatment group, the urinary excretion of potassium was significantly increased by 20.6 mmol/24 h (P< 0.001) during 12 weeks of intervention. Compared to placebo, active treatment was associated with a significant reduction in systolic BP (-5.00 mmHg, 95% CI: -2.13 to -7.88 mmHg, P < 0.001) but not diastolic BP (-0.63 mmHg, 95% CI: -2.49 to1.23 mmHg, P = 0.51) during 12-week intervention.

CONCLUSION

These data indicate that moderate potassium supplementation resulted in a substantial reduction in systolic BP. Our findings suggest that increased potassium intake may play an important role in the prevention and treatment of hypertension in China.

[Application of computer image process to the research on the contact characteristics of subtalar joint]

With the use of computer image processing technology, a new method was proposed for studying the contact characteristics of the subtalar joint. The results showed the total subtalar articulation area was 9.52 +/- 0.40 cm2. On neutral position and under 600 N load, the contact area of the subtalar joint was 2.00 +/- 0.11 cm2. The contact area of the posterior articulation was significantly larger than that of the anterior and medial articulation (p < 0.01). The average contact pressure was 19.3 +/- 1.38 N, the force transmitted by the subtalar was 389.16 +/- 28.75 N, which accounted for about 64.86% of the applied shank load (600 N), and 69.39% of the force was transmitted by the posterior articulation. The posterior articulation plays an important role in the load. The fracture line of the calcaneus often appears in this area.

[Study on the relationship between methylenetetrahydrofolate reductase gene C677T mutation and coronary heart disease]

OBJECTIVE

To investigate whether methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism is linked with coronary heart disease (CHD).

METHODS

Transmission/disequilibrium test(TDT), sib transmission/disequilibrium test(STDT), and sibship disequilibrium test(SDT) were used. Forty-five CHD pedigrees with at least one CHD patient in the first degree relatives of probands were recruited from Oct. 1998 to Feb. 1999. Among those recruited were 21, 2 and 22 pedigrees with the genotypes of both parents known, one parental genotype unknown and both unknown, respectively. MTHFR genotype was measured by PCR-RFLP technique.

RESULTS

Neither the TDT for 23 nuclear families with at least one parental genotype known or the STDT and SDT for 40 sibships found significant difference between the transmitted and untransmitted MTHFR gene 677T allele distributions.

CONCLUSION

The above results suggest that MTHFR gene 677T allele is probably not linked with CHD in Chinese population.

Matrix immobilization enhances the tissue repair activity of growth factor gene therapy vectors

Although growth factor proteins display potent tissue repair activities, difficulty in sustaining localized therapeutic concentrations limits their therapeutic activity. We reasoned that enhanced histogenesis might be achieved by combining growth factor genes with biocompatible matrices capable of immobilizing vectors at delivery sites. When delivered to subcutaneously implanted sponges, a platelet-derived growth factor B-encoding adenovirus (AdPDGF-B) formulated in a collagen matrix enhanced granulation tissue deposition 3- to 4-fold (p < or = 0.0002), whereas vectors encoding fibroblast growth factor 2 or vascular endothelial growth factor promoted primarily angiogenic responses. By day 8 posttreatment of ischemic excisional wounds, collagen-formulated AdPDGF-B enhanced granulation tissue and epithelial areas up to 13- and 6-fold (p < 0.009), respectively, and wound closure up to 2-fold (p < 0.05). At longer times, complete healing without excessive scar formation was achieved. Collagen matrices were shown to retain both vector and transgene products within delivery sites, enabling the transduction and stimulation of infiltrating repair cells. Quantitative PCR and RT-PCR demonstrated both vector DNA and transgene mRNA within wound beds as late as 28 days posttreatment. By contrast, aqueous formulations allowed vector seepage from application sites, leading to PDGF-induced hyperplasia in surrounding tissues but not wound beds. Finally, repeated applications of PDGF-BB protein were required for neotissue induction approaching equivalence to a single application of collagen-immobilized AdPDGF-B, confirming the utility of this gene transfer approach. Overall, these studies demonstrate that immobilizing matrices enable the controlled delivery and activity of tissue promoting genes for the effective regeneration of injured tissues.