Autologous fat grafting after sarcoma surgery: Evaluation of oncological safety

Signal Pathways and microRNAs in Osteosarcoma Growth and the Dual Role of Mesenchymal Stem Cells in Oncogenesis

The major challenges in Osteosarcoma (OS) therapy are its heterogeneity and drug resistance. The development of new therapeutic approaches to overcome the major growth mechanisms of OS is urgently needed. The search for specific molecular targets and promising innovative approaches in OS therapy, including drug delivery methods, is an urgent problem. Modern regenerative medicine focuses on harnessing the potential of mesenchymal stem cells (MSCs) because they have low immunogenicity. MSCs are important cells that have received considerable attention in cancer research. Currently, new cell-based methods for using MSCs in medicine are being actively investigated and tested, especially as carriers for chemotherapeutics, nanoparticles, and photosensitizers. However, despite the inexhaustible regenerative potential and known anticancer properties of MSCs, they may trigger the development and progression of bone tumors. A better understanding of the complex cellular and molecular mechanisms of OS pathogenesis is essential to identify novel molecular effectors involved in oncogenesis. The current review focuses on signaling pathways and miRNAs involved in the development of OS and describes the role of MSCs in oncogenesis and their potential for antitumor cell-based therapy.

[Is it legitimate to propose surgery of the breast area before the end of puberty?]

Breast surgery is usually recommended for women who have completed puberty. Indeed, during adolescence the breast is constantly changing, the patient's weight is often unstable, the risk of inflammatory scars (hypertrophic or keloid) is higher and disturbances of areolar sensitivity can affect the patient's quality of sexual life. In addition, the risk of infection is not negligible, especially during an acne outbreak. In case of early implant placement, iterative changes should be planned. Finally, the result obtained is not always stable but above all the lack of psychological maturity and the legal need to obtain the agreement of both parents are obstacles to early surgery. However, the authors argue for the possibility of surgical correction of the breast around puberty, in particular because of the very clear positive psychological impact. Other arguments are also detailed: to ensure a breast reconstruction in successive stages started early, to limit the repercussions of hypertrophy, to correct thoracic or skin anomalies. These indications are illustrated by numerous clinical cases demonstrating the need for customized surgery on a case-by-case basis.

Research update of adipose tissue-based therapies in regenerative dermatology

Mesenchymal stromal/stem cells (MSCs) have a spontaneous propensity to support tissue homeostasis and regeneration. Among the several sources of MSCs, adipose-derived tissue stem cells (ADSCs) have received major interest due to the higher mesenchymal stem cells concentration, ease, and safety of access. However, since a significant part of the natural capacity of ADSCs to repair damaged tissue is ascribable to their secretory activity that combines mitogenic factors, cytokines, chemokines, lipids, and extracellular matrix components, several studies focused on cell-free strategies. Furthermore, adipose cell-free derivatives are becoming more attractive especially for non-volumizing purposes, such as most dermatological conditions. However, when keratinocytes, fibroblasts, melanocytes, adipocytes, and hair follicle cells might not be locally sourced, graft of materials containing concentrated ADSCs is preferred. The usage of extracellular elements of adipose tissue aims to promote a self-autonomous regenerative microenvironment in the receiving area restoring physiological homeostasis. Hence, ADSCs or their paracrine activity are currently being studied in several dermatological settings including wound healing, skin fibrosis, burn, and aging.The present work analyzing both preclinical and clinical experiences gives an overview of the efficacy of adipose tissue-derivatives like autologous fat, the stromal vascular fraction (SVF), purified ADSCs, secretome and extracellular matrix graft in the field of regenerative medicine for the skin.

Efficacy of adipose-derived stromal vascular fraction cells in the management of chronic ulcers: a randomized clinical trial

Background: Cell therapy is a promising method for improving healing in chronic ulcers through delivery of isolated adipose-derived stromal vascular fraction. Objectives: This study investigates the autologous stem cell yield of adipose tissue and its efficacy in chronic ulcers compared with conventional methods. Methods: This study was a randomized controlled trial. After the study design and protocol were established and ethical committee approval was obtained, we enrolled 100 patients divided into study and control groups. In the study group, we performed debridement and autologous stem cell injection every 3 weeks. The control group was treated with debridement and conventional dressing. Assessments included clinical and histological parameters. Results: The study group showed improved healing. Conclusion: Using autologous adipose-derived stromal vascular fraction cells is an effective treatment method for chronic ulcers. This study was registered on the Pan-African Clinical Trial Registry and the number of the registry was PACTR201709002519185.

Impact of human adipose tissue-derived stem cells on dermatofibrosarcoma protuberans cells in an indirect co-culture: an in vitro study

BACKGROUND

Autologous adipose tissue transfer may be performed for aesthetic needs following the resection of dermatofibrosarcoma protuberans (DFSP), the most common cutaneous soft tissue sarcoma, excluding Kaposi sarcoma. The regenerative effectiveness of cell-assisted lipotransfer is dependent on the presence of adipose tissue-derived stem cells (ADSCs). This is the first study to evaluate the potential oncological risks as ADSCs could unintentionally be sited within the proximity of the tumor microenvironment of DFSP cells.

METHODS

Primary DFSP cells were indirectly co-cultured with ADSCs in a conditioned medium or in a Transwell system. The impact was analyzed by assessing proliferation, migration, invasion, angiogenesis, and tumor-associated genes and proteins. Results of these assays were compared between co-culture and mono-culture conditions.

RESULTS

Our experimental results showed that ADSCs were able to promote proliferation, migration, invasion, and angiogenesis of DFSP cells; this was accompanied by a significant increase in the expression levels of beta-type platelet-derived growth factor receptor, collagen type I alpha 1 chain, vascular endothelial growth factor, hepatocyte growth factor, and basic fibroblast growth factor.

CONCLUSIONS

The current report clearly demonstrates that ADSCs can enhance different malignant properties of DFSP cells in vitro, which should not be neglected when considering the clinical use of human ADSCs and its related derivatives in skin regenerative therapies.

Autologous Fat Grafting for Oncologic Patients: A Literature Review

Autologous fat grafting (AFG) serves as an effective method to address volume defects, contour irregularities, and asymmetry in both aesthetic and reconstructive procedures. In recent years, there has been growing concern about the potential of cancer recurrence and interference with cancer surveillance in oncologic patients receiving AFG. The adipose tissue contains adipose-derived stem cells (ASCs), a specific type of mesenchymal stem cells, that facilitate secretion of numerous growth factors which in turn stimulate tissue regeneration and angiogenesis. As such, it has been theorized that ASCs may also have the potential to stimulate cancer cell proliferation and growth when used in oncologic patients. Multiple research studies have demonstrated the ability of ACSs to facilitate tumor proliferation in animal models. However, clinical research in oncologic patients has yielded contradictory findings. Although the literature pertaining to oncologic safety in head and neck, as well as sarcoma, cancer patients remains limited, studies demonstrate no increased risk of tumor recurrence in these patient populations receiving AFG. Similarly, both the efficacy and safety of AFG have been well established in breast cancer patients through numerous clinical studies. More recently, preclinical research in animal models has shown that AFG has the potential to facilitate tissue regeneration and improve joint contracture following irradiation. Ultimately, further research is needed to elucidate the safety of AFG in a variety of oncologic patients, as well as explore its use in tissue regeneration, particularly in the setting of radiotherapy. Level of Evidence: 4.

The role of reconstructive surgery after soft tissue sarcoma resection

Soft tissue sarcomas are rare malignant tumors with pejorative prognosis. They require a multidisciplinary approach in a specialized hospital belonging to the NetSarc network in France. In all cases treated with curative intent, the objective of excision surgery is to achieve wide, microscopically negative margins (R0 according to the UICC classification). When growing on a limb, sarcomas may threaten functionally relevant structures and even lead to amputation. Nowadays, when combined with radiation therapy, wide exeresis limb-sparing surgery is achievable in 90 to 95% of the cases, of which 25% will nevertheless require reconstructive surgery to preserve the limb, to limit postoperative complications and to manage possible sequelae. Progress in reparative surgery, particularly in microsurgery, has helped not only to improve limb salvage rates but also to create wider margins without altering oncologic goals of curative resection. After determining the range of resection, reconstructive surgery should be tailored to address the tissue defect. The converse is to be strongly discouraged. The extent of resection must not be compromised or reduced in order to facilitate reconstructive surgery. A plastic surgeon must master all the flap techniques, including microsurgery, while taking into account the impact of preoperative and postoperative radiation therapy on previously irradiated tissues or on wounds requiring adjuvant therapy. Recent developments, especially as regards perforator flaps, have helped to enhanced the quality of reconstruction procedure while reducing donor site morbidity. In our experience, perforator flaps are a workhorse in reconstructive surgeries subsequent to soft tissue sarcoma of the extremities. On a parallel track, lipofilling (otherwise known as fat grafting or fat transfer) has become the first-line treatment for patients with post-surgical functional or cosmetic sequalae. It is performed after long-term follow-up during disease-free survival. Strict clinical examination and MRI are mandatory prior to programming any local procedure. Usually, three to four sessions of fat grafting are needed to enhance local trophicity or the cosmetic aspect. Sequalae treatments are of great interest in terms of psychological as well as functional outcome.

Impact of the Different Preparation Methods to Obtain Human Adipose-Derived Stromal Vascular Fraction Cells (AD-SVFs) and Human Adipose-Derived Mesenchymal Stem Cells (AD-MSCs): Enzymatic Digestion Versus Mechanical Centrifugation

Autologous therapies using adipose-derived stromal vascular fraction (AD-SVFs) and adult adipose-derived mesenchymal stem cells (AD-MSCs) warrant careful preparation of the harvested adipose tissue. Currently, no standardized technique for this preparation exists. Processing quantitative standards (PQSs) define manufacturing quantitative variables (such as time, volume, and pressure). Processing qualitative standards (PQLSs) define the quality of the materials and methods in manufacturing. The purpose of the review was to use PQSs and PQLSs to report the in vivo and in vitro results obtained by different processing kits that use different procedures (enzymatic vs. non-enzymatic) to isolate human AD-SVFs/AD-MSCs. PQSs included the volume of fat tissue harvested and reagents used, the time/gravity of centrifugation, and the time, temperature, and tilt level/speed of incubation and/or centrifugation. PQLSs included the use of a collagenase, a processing time of 30 min, kit weight, transparency of the kit components, the maintenance of a closed sterile processing environment, and the use of a small centrifuge and incubating rocker. Using a kit with the PQSs and PQLSs described in this study enables the isolation of AD-MSCs that meet the consensus quality criteria. As the discovery of new critical quality attributes (CQAs) of AD-MSCs evolve with respect to purity and potency, adjustments to these benchmark PQSs and PQLs will hopefully isolate AD-MSCs of various CQAs with greater reproducibility, quality, and safety. Confirmatory studies will no doubt need to be completed.

Adipose-Derived Stem Cells in Cancer Progression: New Perspectives and Opportunities

Growing importance has been attributed to interactions between tumors, the stromal microenvironment and adult mesenchymal stem cells. Adipose-derived stem cells (ASCs) are routinely employed in regenerative medicine and in autologous fat transfer procedures. To date, clinical trials have failed to demonstrate the potential pro-oncogenic role of ASC enrichment. Nevertheless, some pre-clinical studies from in vitro and in vivo models have suggested that ASCs act as a potential tumor promoter for different cancer cell types, and support tumor progression and invasiveness through the activation of several intracellular signals. Interaction with the tumor microenvironment and extracellular matrix remodeling, the exosomal release of pro-oncogenic factors as well as the induction of epithelial-mesenchymal transitions are the most investigated mechanisms. Moreover, ASCs have also demonstrated an elective tumor homing capacity and this tumor-targeting capacity makes them a suitable carrier for anti-cancer drug delivery. New genetic and applied nanotechnologies may help to design promising anti-cancer cell-based approaches through the release of loaded intracellular nanoparticles. These new anti-cancer therapies can more effectively target tumor cells, reaching higher local concentrations even in pharmacological sanctuaries, and thus minimizing systemic adverse drug effects. The potential interplay between ASCs and tumors and potential ASCs-based therapeutic approaches are discussed.

Concise Review: Adipose-Derived Stem Cells (ASCs) and Adipocyte-Secreted Exosomal microRNA (A-SE-miR) Modulate Cancer Growth and proMote Wound Repair

Adipose-derived stem cells (ASCs) have been routinely used from several years in regenerative surgery without any definitive statement about their potential pro-oncogenic or anti-oncogenic role. ASCs has proven to favor tumor progression in several experimental cancer models, playing a central role in regulating tumor invasiveness and metastatic potential through several mechanisms, such as the paracrine release of exosomes containing pro-oncogenic molecules and the induction of epithelial-mesenchymal transition. However, the high secretory activity and the preferential tumor-targeting make also ASCs a potentially suitable vehicle for delivery of new anti-cancer molecules in tumor microenvironment. Nanotechnologies, viral vectors, drug-loaded exosomes, and micro-RNAs (MiR) represent additional new tools that can be applied for cell-mediated drug delivery in a tumor microenvironment. Recent studies revealed that the MiR play important roles in paracrine actions on adipose-resident macrophages, and their dysregulation has been implicated in the pathogenesis of obesity, diabetes, and diabetic complications as wounds. Numerous MiR are present in adipose tissues, actively participating in the regulation of adipogenesis, adipokine secretion, inflammation, and inter-cellular communications in the local tissues. These results provide important insights into Adipocyte-secreted exosomal microRNA (A-SE-MiR) function and they suggest evaluating the potential role of A-SE-MiR in tumor progression, the mechanisms underlying ASCs-cancer cell interplay and clinical safety of ASCs-based therapies.