Effect of Adipose-Derived Stem Cells on Head and Neck Squamous Cell Carcinoma

Autologous Fat Grafting for Functional and Aesthetic Improvement in Patients with Head and Neck Cancer: A Systematic Review

INTRODUCTION

The efficacy and safety of autologous fat grafting for use in oncology patients are controversial. Patients with head and neck cancer have complex anatomy and require reconstructive repair of the head and neck after comprehensive treatment. The limited additional aesthetic and functional studies on the use of autologous fat fillers in patients with head and neck cancer are unclear. This study systematically evaluates the additional function of autologous fat fillers in the head and neck and systematically reviews issues related to autologous fat grafting after comprehensive head and neck cancer treatment, including current indications, techniques, potential complications, graft survival, and patient satisfaction.

METHODS

A systematic literature review was performed using PubMed, The Cochrane Library, EMBASE, and Web of Science (last accessed on January 9, 2023).

RESULTS

A total of 249 cases of autologous fat fillers in patients with head and neck cancer were reported in 10 clinical publications. Observations were based mainly on subjective physician and patient evaluation indicators, and all studies reported the beneficial effects of autologous fat fillers on aesthetics and function after treatment for head and neck cancer.

CONCLUSIONS

Autologous fat fillers are effective in improving the aesthetics and function of head and neck cancer, and due to the limitations of the original study, future studies with large samples are needed to support this. PROSPERO registration number is CRD42020222870.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Primary injection laryngoplasty after chordectomy for small glottic carcinomas

OBJECTIVES

The purpose of this study was to analyze the short- and middle-term effects of primary injection laryngoplasty in patients having tumor resection within the same surgery concerning the vocal outcome. Injection laryngoplasty was performed after harvesting autologous adipose tissue via lipoaspiration.

METHODS

A prospective study was performed with 16 patients (2 female; 14 male) who received tumor resection and an injection laryngoplasty using autologous adipose tissue during a single stage procedure. Multidimensional voice evaluation including videostroboscopy, patient self-assessment, voice perception, aerodynamics, and acoustic parameters was performed preoperatively, as well as 1.5, 3 and 6 months postoperatively.

RESULTS

Results show an improvement in the roughness-breathiness-hoarseness (RBH) scale, voice dynamics and subjective voice perception 6 months postoperatively. Maintenance of Voice Handycap Index, jitter and shimmer could be observed 6 months postoperatively. There was no deterioration in RBH and subjective voice perception 2 and 6 weeks postoperatively. No complications occurred in the fat harvesting site.

CONCLUSIONS

Using the lipoaspiration and centrifugation approach, primary fat injection laryngoplasty shows short-term maintenance und middle-term improvement in voice quality in patients with vocal fold defect immediately after chordectomy 6 months postoperatively. Cancer recurrence rate is comparable to the reported cancer recurrence rate for laryngeal carcinoma and thus not elevated through primary augmentation.

The effect of obesity on adipose-derived stromal cells and adipose tissue and their impact on cancer

The significant increase in the incidence of obesity represents the next global health crisis. As a result, scientific research has focused on gaining deeper insights into obesity and adipose tissue biology. As a result of the excessive accumulation of adipose tissue, obesity results from hyperplasia and hypertrophy within the adipose tissue. The functional alterations in the adipose tissue are a confounding contributing factor to many diseases, including cancer. The increased incidence and aggressiveness of several cancers, including colorectal, postmenopausal breast, endometrial, prostate, esophageal, hematological, malignant melanoma, and renal carcinomas, result from obesity as a contributing factor. The increased morbidity and mortality of obesity-associated cancers are attributable to increased hormones, adipokines, and cytokines produced by the adipose tissue. The increased adipose tissue levels observed in obese patients result in more adipose stromal/stem cells (ASCs) distributed throughout the body. ASCs have been shown to impact cancer progression in vitro and in preclinical animal models. ASCs influence tumor biology via multiple mechanisms, including the increased recruitment of ASCs to the tumor site and increased production of cytokines and growth factors by ASCs and other cells within the tumor stroma. Emerging evidence indicates that obesity induces alterations in the biological properties of ASCs, subsequently leading to enhanced tumorigenesis and metastasis of cancer cells. As the focus of this review is the interaction and impact of ASCs on cancer, the presentation is limited to preclinical data generated on cancers in which there is a demonstrated role for ASCs, such as postmenopausal breast, colorectal, prostate, ovarian, multiple myeloma, osteosarcoma, cervical, bladder, and gastrointestinal cancers. Our group has investigated the interactions between obesity and breast cancer and the mechanisms that regulate ASCs and adipocytes in these different contexts through interactions between cancer cells, immune cells, and other cell types present in the tumor microenvironment (TME) are discussed. The reciprocal and circular feedback loop between obesity and ASCs and the mechanisms by which ASCs from obese patients alter the biology of cancer cells and enhance tumorigenesis will be discussed. At present, the evidence for ASCs directly influencing human tumor growth is somewhat limited, though recent clinical studies suggest there may be some link.

Human Mesenchymal Stromal Cells Do Not Cause Radioprotection of Head-and-Neck Squamous Cell Carcinoma

Radiotherapy of head-and-neck squamous cell carcinoma (HNSCC) can cause considerable normal tissue injuries, and mesenchymal stromal cells (MSCs) have been shown to aid regeneration of irradiation-damaged normal tissues. However, utilization of MSC-based treatments for HNSCC patients undergoing radiotherapy is hampered by concerns regarding potential radioprotective effects. We therefore investigated the influence of MSCs on the radiosensitivity of HNSCCs. Several human papillomavirus (HPV)-negative and HPV-positive HNSCCs were co-cultured with human bone marrow-derived MSCs using two-dimensional and three-dimensional assays. Clonogenic survival, proliferation, and viability of HNSCCs after radiotherapy were assessed depending on MSC co-culture. Flow cytometry analyses were conducted to examine the influence of MSCs on irradiation-induced cell cycle distribution and apoptosis induction in HNSCCs. Immunofluorescence stainings of γH2AX were conducted to determine the levels of residual irradiation-induced DNA double-strand breaks. Levels of connective tissue growth factor (CTGF), a multifunctional pro-tumorigenic cytokine, were analyzed using enzyme-linked immunosorbent assays. Neither direct MSC co-culture nor MSC-conditioned medium exerted radioprotective effects on HNSCCs as determined by clonogenic survival, proliferation, and viability assays. Consistently, three-dimensional microwell arrays revealed no radioprotective effects of MSCs. Irradiation resulted in a G2/M arrest of HNSCCs at 96 h independently of MSC co-culture. HNSCCs’ apoptosis rates were increased by irradiation irrespective of MSCs. Numbers of residual γH2AX foci after irradiation with 2 or 8 Gy were comparable between mono- and co-cultures. MSC mono-cultures and HNSCC-MSC co-cultures exhibited comparable CTGF levels. We did not detect radioprotective effects of human MSCs on HNSCCs. Our results suggest that the usage of MSC-based therapies for radiotherapy-related toxicities in HNSCC patients may be safe in the context of absent radioprotection.

Human Adipose-Derived Stem/Stromal Cells Promote Proliferation and Migration in Head and Neck Cancer Cells

Simple Summary

Fat grafts obtained from a minimal invasive liposuction device contain multipotent stem cells termed adipose-derived stem/stromal cells (ASCs). ASCs can be used for their proposed wound healing relevant characteristics, including for tissue defects in cancer patients. For head and neck cancers, little is known about the effects of ASCs on tumor cells. Using supernatants of ASCs from five patients in different functional experiments, this study aimed to investigate how ASCs influence tumor growth, invasive properties, and neoangiogenesis. The data show that all mentioned characteristics are promoted by fat graft stem cells in vitro in head and neck cancer cell lines. Although clinical relevance of these in vitro findings is unclear, due to the lack of in vivo and clinical data, fat grafts should be used cautiously and complete removal of tumor should be ensured before augmentation in head and neck cancer patients is performed.

Abstract

Human adipose-derived stem/stromal cells (ASCs) are increasingly used as auto-transplants in regenerative medicine to restore tissue defects or induce wound healing, especially in cancer patients. The impact of ASCs on squamous cell carcinoma of the upper aerodigestive tract (UAT) including head and neck and esophageal squamous cell carcinoma (HNSCC and ESCC) is not yet fully understood. ASCs were cultured from subcutaneous, abdominal lipoaspirates of five patients, who received auto-transplants to the head and neck. Supernatants were tested for paracrine effects in functional in vitro assays of proliferation of HNSCC tumor cell line FaDu and ESCC cell line Kyse30, and their cell migration/invasion capacities in Boyden chambers, in addition to endothelial tube formation assay using human umbilical vein endothelial cells (HUVECs). All ASC-derived supernatants enhanced proliferation of FaDu cells, invasive migration, and tube formation by HUVECs, compared to controls. Of five patients’ lipoaspirates, ASC-derived supernatants of four patients increased proliferation and invasive migration in Kyse30 cells. The data suggests that ASCs can promote tumor cell proliferation, invasiveness, and neo-angiogenesis in these tumor cell lines of the UAT and HUVEC in a paracrine manner. Although clinical studies on the subject of oncological safety are still needed, these findings emphasize the importance of complete tumor removal before ASCs are used in the head and neck.

Regenerative medicine approaches for the management of respiratory tract fistulas

Respiratory tract fistulas (or fistulae) are abnormal communications between the respiratory system and the digestive tract or the adjacent organs. The origin can be congenital or, more frequently, iatrogenic and the clinical presentation is heterogeneous. Respiratory tract fistulas can lead to severely reduced health-related quality of life and short survival. Therapy mainly relies on endoscopic surgical interventions but patients often require prolonged hospitalization and may develop complications. Therefore, more conservative regenerative medicine approaches, mainly based on lipotransfer, have also been investigated. Adipose tissue can be delivered either as unprocessed tissue, or after enzymatic treatment to derive the cellular stromal vascular fraction. In the current narrative review, we provide an overview of the main tissue/cell-based clinical studies for the management of various types of respiratory tract fistulas or injuries. Clinical experience is limited, as most of the studies were performed on a small number of patients. Albeit a conclusive proof of efficacy cannot be drawn, the reviewed studies suggest that grafting of adipose tissue-derived material may represent a minimally invasive and conservative treatment option, alternative to more aggressive surgical procedures. Knowledge on safety and tolerability acquired in prior studies can lead to the design of future, larger trials that may exploit innovative procedures for tissue processing to further improve the clinical outcome.

Adipose-Derived Mesenchymal Stem Cells Enhance Ovarian Cancer Growth and Metastasis by Increasing Thymosin Beta 4X-Linked Expression

As shown in our previous studies, growth and metastasis of ovarian cancer can be regulated by adipose-derived mesenchymal stem cells (ADSCs). However, the underlying mechanism has not yet been revealed. In this study, a proteomics analysis was performed to compare protein expression treated with and without ADSCs in ovarian cancer cells. Protein levels were altered in ovarian cancer cells due to the treatment of ADSCs. Thymosin beta 4 X-linked (TMSB4X) levels changed dramatically, and this protein was identified as one of the most important candidate molecules contributing to the tumour-promoting effects of ADSCs. Compared with the cells that are cultured in the normal growth medium, the TMSB4X levels cultured in ADSC-conditioned medium increased significantly in ovarian cancer cells. Furthermore, the growth and invasion of cancer cells were decreased, even in the ADSC-conditioned medium treatment group (P < 0.05), by the inhibition of TMSB4X. As shown in the bioluminescence images captured in vivo, increased ovarian cancer's growth and metastasis, along with elevated TMSB4X expression, were observed in the group of ADSC-conditioned medium, and the tumour-promoting effect of ADSCs was attenuated by the inhibition of TMSB4X. Based on our findings, increased TMSB4X expression may play a role in accelerating the ADSC-mediated proliferation, invasion, and migration of ovarian cancers.

Regenerative Capacity of Adipose Derived Stem Cells (ADSCs), Comparison with Mesenchymal Stem Cells (MSCs)

Adipose tissue is now on the top one of stem cell sources regarding its accessibility, abundance, and less painful collection procedure when compared to other sources. The adipose derived stem cells (ADSCs) that it contains can be maintained and expanded in culture for long periods of time without losing their differentiation capacity, leading to large cell quantities being increasingly used in cell therapy purposes. Many reports showed that ADSCs-based cell therapy products demonstrated optimal efficacy and efficiency in some clinical indications for both autologous and allogeneic purposes, hence becoming considered as potential tools for replacing, repairing, and regenerating dead or damaged cells. In this review, we analyzed the therapeutic advancement of ADSCs in comparison to bone marrow (BM) and umbilical cord (UC)-mesenchymal stem cells (MSCs) and designed the specific requirements to their best clinical practices and safety. Our analysis was focused on the ADSCs, rather than the whole stromal vascular fraction (SVF) cell populations, to facilitate characterization that is related to their source of origins. Clinical outcomes improvement suggested that these cells hold great promise in stem cell-based therapies in neurodegenerative, cardiovascular, and auto-immunes diseases.

Regenerative Capacity of Adipose Derived Stem Cells (ADSCs), Comparison with Mesenchymal Stem Cells (MSCs)

Adipose tissue is now on the top one of stem cell sources regarding its accessibility, abundance, and less painful collection procedure when compared to other sources. The adipose derived stem cells (ADSCs) that it contains can be maintained and expanded in culture for long periods of time without losing their differentiation capacity, leading to large cell quantities being increasingly used in cell therapy purposes. Many reports showed that ADSCs-based cell therapy products demonstrated optimal efficacy and efficiency in some clinical indications for both autologous and allogeneic purposes, hence becoming considered as potential tools for replacing, repairing, and regenerating dead or damaged cells. In this review, we analyzed the therapeutic advancement of ADSCs in comparison to bone marrow (BM) and umbilical cord (UC)-mesenchymal stem cells (MSCs) and designed the specific requirements to their best clinical practices and safety. Our analysis was focused on the ADSCs, rather than the whole stromal vascular fraction (SVF) cell populations, to facilitate characterization that is related to their source of origins. Clinical outcomes improvement suggested that these cells hold great promise in stem cell-based therapies in neurodegenerative, cardiovascular, and auto-immunes diseases.

STAT3 activation by IL-6 from adipose-derived stem cells promotes endometrial carcinoma proliferation and metastasis

Endometrial cancer is the most common gynaecological cancer, and its incidence is increasing. Obesity is a well-recognized risk factor for endometrial cancer, and the mechanisms by which adipose tissue influences tumour development remain controversial. In this study, we examined the high IL-6 level in the ADSCs supernatant following treatment of endometrial cancer cell CM. Then, the activation of STAT3, a major tumourigenic IL-6 effector, was examined in ADSCs CM treated endometrial cancer cells. Conditioned ADSC medium was used to stimulate endometrial cancer cell growth in vitro. Similar to IL-6, ADSC-conditioned medium significantly promoted endometrial cancer growth and invasion. Furthermore, siRNA-mediated STAT3 inhibition in endometrial cancer cells decreased the ADSC-mediated promotion of cell proliferation and invasion. In addition, a subcutaneous nude mouse model of endometrial cancer was established to monitor the tumour-promoting effect of ADSCs. ADSC-conditioned medium promoted tumour growth, and STAT3 inhibition attenuated this effect. Based on these data, ADSCs promote endometrial cancer progression by the STAT3 signalling pathway.