Human Amniotic Membrane and Its Anti-cancer Mechanism: a Good Hope for Cancer Therapy

Role of dehydrated human amnion/chorion membrane in enhancing functional outcomes after robot-assisted radical prostatectomy: a systematic review and meta-analysis

BACKGROUND

Dehydrated human amnion/chorion membrane (dHACM) has shown potential in enhancing neurovascular recovery and functional outcomes in robot-assisted radical prostatectomy (RARP).

AIM

To evaluate the effects of dHACM on continence recovery, sexual function, and oncological outcomes in patients undergoing RARP.

METHODS

A systematic review and meta-analysis were conducted following PRISMA guidelines, analyzing data from PubMed, Cochrane, and EMBASE. Six retrospective studies comparing RARP with and without dHACM were included. Odds ratios (OR) and standardized mean differences (SMD) were calculated using a random-effects model.

OUTCOMES

The primary outcomes were continence and potency recovery, and secondary outcomes included biochemical recurrence (BCR).

RESULTS

The meta-analysis included 4072 patients (1699 experimental and 2373 control). dHACM significantly improved early continence recovery (SMD 1.78, 95% CI 1.26-2.34) at <3, 3, and 6 months postoperatively (OR 1.95, 95% CI 1.13-3.36; OR 2.17, 95% CI 1.52-3.09; and OR 1.70, 95% CI 1.10-2.63, respectively). Time to potency recovery was shorter (SMD -0.55, 95% CI -0.67 to -0.43), with significant improvements at <3, 3, 6, and 9 months (OR 1.67, 95% CI 1.25-2.23; OR 1.27, 95% CI 1.06-1.53; OR 1.41, 95% CI 1.15-1.72; and OR 1.51, 95% CI 1.16-1.97, respectively). There were no significant differences in BCR (OR 0.85, 95% CI 0.54-1.35).

CLINICAL IMPLICATIONS

dHACM offers potential as an adjunct to enhance functional recovery following RARP without compromising oncologic safety, but further high-quality studies are needed.

STRENGTHS & LIMITATIONS

Strengths include a comprehensive analysis of early functional outcomes and low heterogeneity in early potency and continence data. Limitations include reliance on retrospective studies and lack of randomized controlled trials.

CONCLUSION

dHACM may accelerate continence and sexual function recovery in early period after RARP while maintaining oncological outcomes, but further randomized studies are necessary to confirm these findings.

Amnion-derived hydrogels as a versatile platform for regenerative therapy: from lab to market

In recent years, the amnion (AM) has emerged as a versatile tool for stimulating tissue regeneration and has been of immense interest for clinical applications. AM is an abundant and cost-effective tissue source that does not face strict ethical issues for biomedical applications. The outstanding biological attributes of AM, including side-dependent angiogenesis, low immunogenicity, anti-inflammatory, anti-fibrotic, and antibacterial properties facilitate its usage for tissue engineering and regenerative medicine. However, the clinical usage of thin AM sheets is accompanied by some limitations, such as handling without folding or tearing and the necessity for sutures to keep the material over the wound, which requires additional considerations. Therefore, processing the decellularized AM (dAM) tissue into a temperature-sensitive hydrogel has expanded its processability and applicability as an injectable hydrogel for minimally invasive therapies and a source of bioink for the fabrication of biomimetic tissue constructs by recapitulating desired biochemical cues or pre-defined architectural design. This article reviews the multi-functionality of dAM hydrogels for various biomedical applications, including skin repair, heart treatment, cartilage regeneration, endometrium regeneration, vascular graft, dental pulp regeneration, and cell culture/carrier platform. Not only recent and cutting-edge research is reviewed but also available commercial products are introduced and their main features and shortcomings are elaborated. Besides the great potential of AM-derived hydrogels for regenerative therapy, intensive interdisciplinary studies are still required to modify their mechanical and biological properties in order to broaden their therapeutic benefits and biomedical applications. Employing additive manufacturing techniques (e.g., bioprinting), nanotechnology approaches (e.g., inclusion of various bioactive nanoparticles), and biochemical alterations (e.g., modification of dAM matrix with photo-sensitive molecules) are of particular interest. This review article aims to discuss the current function of dAM hydrogels for the repair of target tissues and identifies innovative methods for broadening their potential applications for nanomedicine and healthcare.

Human amniotic membrane as a multifunctional biomaterial: recent advances and applications

The developing fetus is wrapped by a human amniotic membrane or amnion. Amnion is a promising human tissue allograft in clinical application because of its chemical composition, collagen-based, and mechanical properties of the extracellular matrix. In addition, amnion contains cells and growth factors; therefore, meets the essential parameters of tissue engineering. No donor morbidity, easy processing and storage, fewer ethical issue, anti-inflammatory, antioxidant, antibacterial, and non-immunogenic properties are other advantages of amnion usage. For these reasons, amnion can resolve some bottlenecks in the regenerative medicine issues such as tissue engineering and cell therapy. Over the last decades, biomedical applications of amnion have evolved from a simple sheet for skin or cornea repair to high-technology applications such as amnion nanocomposite, powder, or hydrogel for the regeneration of cartilage, muscle, tendon, and heart. Furthermore, amnion has anticancer as well as drug/cell delivery capacity. This review highlights various ancient and new applications of amnion in research and clinical applications, from regenerative medicine to cancer therapy, focusing on articles published during the last decade that also revealed information regarding amnion-based products. Challenges and future perspectives of the amnion in regenerative medicine are also discussed.

Biological properties and surgical applications of the human amniotic membrane

The amniotic membrane (AM) is the inner part of the placenta. It has been used therapeutically for the last century. The biological proprieties of AM include immunomodulatory, anti-scarring, anti-microbial, pro or anti-angiogenic (surface dependent), and tissue growth promotion. Because of these, AM is a functional tissue for the treatment of different pathologies. The AM is today part of the treatment for various conditions such as wounds, ulcers, burns, adhesions, and skin injury, among others, with surgical resolution. This review focuses on the current surgical areas, including gynecology, plastic surgery, gastrointestinal, traumatology, neurosurgery, and ophthalmology, among others, that use AM as a therapeutic option to increase the success rate of surgical procedures. Currently there are articles describing the mechanisms of action of AM, some therapeutic implications and the use in surgeries of specific surgical areas, this prevents knowing the therapeutic response of AM when used in surgeries of different organs or tissues. Therefore, we described the use of AM in various surgical specialties along with the mechanisms of action, helping to improve the understanding of the therapeutic targets and achieving an adequate perspective of the surgical utility of AM with a particular emphasis on regenerative medicine.

The Effects of Amniotic Membrane Transplantation on Vocal Fold Regeneration

OBJECTIVES/HYPOTHESIS

Vocal fold (VF) scar and sulcus cause severe vocal problems, but optimal methods have not been established. Total replacement of the mucosa is required particularly for cases in which the whole lamina propria is occupied by severe fibrosis and vibratory function is totally lost. The amniotic membrane (AM) has been proven to have regenerative potential, as it contains stem cells and growth factors. The current study investigated the biocompatibility and effects of AM for regeneration of the VF mucosa.

STUDY DESIGN

In vitro and in vivo studies.

METHODS

Vocal fold fibroblasts (VFFs) from 13 Sprague-Dawley rats were seeded on AM and subjected to histology and immunohistochemistry, and gene expressions in the VFFs on AM were examined in in vitro study. Twelve New Zealand White rabbits were used in in vivo study. VFs were stripped down and were reconstructed with AM. The regenerative effects were examined 3 months later by histological examination.

RESULTS

In vitro study indicated VFFs survived on AM and stained positively for Ki67, vimentin, and fibronectin. Gene expressions of Has1, Has2, and Hgf were significantly increased in the VFFs on AM compared with the other groups. The in vivo study indicated AM-transplanted VFs showed a significantly higher density of hyaluronic acid and lower density of collagen compared with sham VFs.

CONCLUSIONS

The current preliminary study suggests biocompatibility and possible regenerative effects of AM for VFs.

LEVEL OF EVIDENCE

NA Laryngoscope, 2021.

Tumor Targeting by Conditioned Medium Derived From Human Amniotic Membrane: New Insight in Breast Cancer Therapy

Objectives:

Traditional breast cancer treatments have challenges including inefficiency, multidrug resistance, severe side effects, and targeting non-specifically. The development of alternative treatment strategies has attracted a great deal of interest. Using the amniotic membrane has become a promising and convenient new approach for cancer therapy. This study aimed to evaluate the anti-cancer ability of conditioned medium extracted from the human amniotic membrane (hAM-CM) on breast cancer cells.

Methods:

Conditioned medium was collected after 48 h incubation of hAM in epithelial up manner. MTT, cell cycle, apoptosis, colony formation, and sphere assays were used to determine the impact of hAM-CM on breast cancer cell lines. The effects of hAM-CM on the migration and invasion of breast cancer cells were determined using scratch wound healing and transwell assays, respectively.

Results:

Based on the results, cell viability was significantly decreased by hAM-CM in a dose-dependent manner. The hAM-CM remarkably induced apoptosis and necrosis of cancer cells. Moreover, cell migration and invasion potential of cancer cells decreased after the hAM-CM treatment. Further, both the number of colonies and their morphologies were affected by the treatment. In the treated group, a significant decrease in the number of colonies along with an obvious change in their morphologies from holoclone shape to a dominant paracolone structure was observed.

Conclusion:

Our results indicate that the conditioned medium derived from the human amniotic membrane able to inhibit proliferation and metastasis of tumor cells and can be considered a natural and valuable candidate for breast cancer therapy.

Update review on five top clinical applications of human amniotic membrane in regenerative medicine

Due to the increasing number of studies performed in the field of regenerative medicine during the last two decades, more analytic studies are still needed to clarify the future prospect of this area of science. The main aim of this research was to review the clinical applications of human Amniotic membrane in the field of regenerative medicine critically. Furthermore, in the light of increasing numbers of available products derived from amniotic membrane, we aimed look in depth to see whether regenerative medicine research strategies have a place in the clinical setting. More specifically, in the present study, we attempted to provide insight on developing the new indication for more research and in the next step, for market leaders companies to expand cost-effectiveness of new derived AM products. 20 companies or distributers have offered some commercial products in this field. Survey on more than 90 clinical trials in last five years showed dermatology (and more specific wound healing), orthopedic, and ophthalmology are heavily biased toward multibillion dollar industry. Moreover, urology and dentistry with fewer numbers of clinical data in comparison with the above-mentioned areas, currently are in the path of translation (especially dentistry). In addition, otolaryngology and oncology with the lowest number showed more potential of research thorough understanding the properties that will help guiding the use of AM-derived products in these two areas in future. More than 50% of clinical studies were done or are developing in USA, which have the biggest share in market products. Subsequently, China, Egypt, India, Iran, and Germany with the ongoing clinical trials in different phases may have more approved products in near future.

Amniotic Membrane Transplantation in Ophthalmology: An Updated Perspective

Aim

The aim of this paper is to provide a succinct literature review of the different clinical applications for AMT usage in an ophthalmic setting, ranging from commonly used applications to less mainstream approaches. The hope is that this review enables the reader to have a better understanding of the biological properties of amnion as well as the indications and scenarios in which AMT can be used, whilst presenting relevant evidence from within the literature which may be of interest. We also provide an update on the methods of preservation of amniotic membrane and the application methodologies.

Methods

Literature search. A PubMed search was performed using the search terms “amniotic membrane transplant”, “amnion AND cornea”, amnion AND ophthalmology”, “amnion AND ocular surface” and “Amnion AND eye”. A full review of the literature using the PubMed database was conducted up until 01/05/20. The articles used were written in English, with all articles accessed in full. Both review articles and original articles were used for this review. All full publications related to ophthalmology were considered.

The biological mechanism involved in anticancer properties of amniotic membrane

The main role of amniotic membrane (AM), or amnion, is to protect the fetus from drying out and create an appropriate environment for its growth. AM is also a suitable candidate for the treatment of various diseases due to its unique characteristics. In recent years, a new line of research has focused on the anticancer properties of amnion and its potential use in cancer treatment. The in vitro and in vivo studies indicate the anti-proliferative and proapoptotic activities, as well as the angioregulatory and immunomodulatory properties of the amniotic membrane. However, the exact mechanism and molecular basis of these anticancer effects of AM are not fully elucidated. This paper presents an overview of the latest findings and knowledge about the anticancer effects of AM and its underlying molecular mechanisms, which is crucial for the application of amnion in cancer therapy.