Amniotic membrane is a potential regenerative option for chronic non-healing wounds: a report of five cases receiving dehydrated human amnion/chorion membrane allograft

A case series of five patients with a total of six chronic non-healing wounds (>30 day duration) were non-randomly selected to evaluate the performance, safety and handling properties of dehydrated human amnion/chorion membrane allograft, an amniotic membrane scaffolding product. The patients had lower extremity wounds that had previously failed standard of care within a university outpatient/inpatient wound healing programme. Five wounds treated with dehydrated amnion/chorion membrane allograft showed a mean 43% area reduction from baseline (51% median) at 3 weeks into treatment and completely healed with a 64-day median time to closure (SD ±27·6 days). One wound worsened at 3 weeks and was found to have a complete central vein obstruction that was treated with long-term mild compression but still eventually healed at 6 months. Removing this outlier, the four responding wounds had a 72% mean and 69% median change in area from baseline, at the 3 week point. All five patients received only one application of dehydrated human amnion/chorion membrane allograft, and there were no adverse events. The product was easy to use, administer and handle. In summary, dehydrated human amnion/chorion membrane allograft appears to be a safe, effective and easy to use therapy for chronic non-healing wounds. This study describes the details of these clinical cases and provides an overview of the current evidence on the use of amniotic tissue in clinical practice.

Macrophage PPARγ and impaired wound healing in type 2 diabetes

Macrophages undergo a transition from pro-inflammatory to healing-associated phenotypes that is critical for efficient wound healing. However, the regulation of this transition during normal and impaired healing remains to be elucidated. In our studies, the switch in macrophage phenotypes during skin wound healing was associated with up-regulation of the peroxisome proliferator-activated receptor (PPAR)γ and its downstream targets, along with increased mitochondrial content. In the setting of diabetes, up-regulation of PPARγ activity was impaired by sustained expression of IL-1β in both mouse and human wounds. In addition, experiments with myeloid-specific PPARγ knockout mice indicated that loss of PPARγ in macrophages is sufficient to prolong wound inflammation and delay healing. Furthermore, PPARγ agonists promoted a healing-associated macrophage phenotype both in vitro and in vivo, even in the diabetic wound environment. Importantly, topical administration of PPARγ agonists improved healing in diabetic mice, suggesting an appealing strategy for down-regulating inflammation and improving the healing of chronic wounds.

Stem Cells and Healing: Impact on Inflammation

SIGNIFICANCE

The number of patients with nonhealing wounds has rapidly accelerated over the past 10 years in both the United States and worldwide. Some causative factors at the macro level include an aging population, epidemic numbers of obese and diabetic patients, and an increasing number of surgical procedures. At the micro level, chronic inflammation is a consistent finding.

RECENT ADVANCES

A number of treatment modalities are currently used to accelerate wound healing, including energy-based modalities, scaffoldings, the use of mechano-transduction, cytokines/growth factors, and cell-based therapies. The use of stem cell therapy has been hypothesized as a potentially useful adjunct for nonhealing wounds. Specifically, mesenchymal stem cells (MSCs) have been shown to improve wound healing in several studies. Immune modulating properties of MSCs have made them attractive treatment options.

CRITICAL ISSUES

Current limitations of stem cell therapy include the potentially large number of cells required for an effect, complex preparation and delivery methods, and poor cell retention in targeted tissues. Comparisons of published in-vitro and clinical trials are difficult due to cell preparation techniques, passage number, and the impact of the micro-environment on cell behavior.

FUTURE DIRECTIONS

MSCs may be more useful if they are preactivated with inflammatory cytokines such as tumor necrosis factor alpha or interferon gamma. This article will review the current literature with regard to the use of stem cells for wound healing. In addition the anti-inflammatory effects of MSCs will be discussed along with the potential benefits of stem cell preactivation.

Prognostic significance of NSE mRNA in advanced NSCLC treated with gefitinib

PURPOSE

Current knowledge of the prognostic biomarkers of advanced non-small cell lung cancer (NSCLC) treated with gefitinib is poor. NSE mRNA as a potential prognostic biomarker of the effectiveness of gefitinib treatment in NSCLC, especially in the Chinese population, needs to be further validated.

PATIENTS AND METHODS

We retrospectively reviewed 168 advanced NSCLC patients treated with gefitinib between May 2006 and July 2010. NSE mRNA was measured using quantitative RT-PCR analysis for correlation with the clinical outcomes.

RESULTS

We found that NSE mRNA expression was inversely correlated with sensitivity to gefitinib in NSCLC patients. Patients without elevated NSE mRNA had a more RR (CR + RR) 45.1 % than elevated 18.9 % (P = 0.0005). Moreover, the time to progression was 6.0 versus 4.2 months, respectively. Log-rank test was marginally significant (χ(2) = 12.11, P = 0.0007) and Cox multivariate analysis revealed that NSE mRNA (HR = 3.076; 95 % CI 1.943-4.870; P < 0.0001) was an independent prognostic factor of NSCLC patients in the Chinese population.

CONCLUSION

For NSCLC patients treated with gefitinib, patients without elevated NSE mRNA had a better prognosis than those with elevated NSE mRNA. Pretreatment NSE mRNA holds great potential as a prognostic biomarker in advanced NSCLC. Therefore, it is proposed that NSE mRNA should be routinely detected to screen patients who are more likely to benefit from gefitinib-based treatment.