The risk of malignancies in patients receiving hematopoietic stem cell transplantation: a systematic review and meta-analysis

Dentistry consensus on HSCT - Part III: Special topics - Dentistry on HSCT

Patients undergoing hematopoietic stem cell transplantation (HSCT) might present acute and late toxicities and the oral tissues are frequently affected. With the survival increasing, patients show late and long-term morbidities, and there is an important association between the general and the oral health. The first and second parts of this Consensus have showed the importance of the adequacy of oral health in the pre-HSCT, and the main alterations and oral care during the period of admission for HSCT. This third part aims to review specific themes of post-HSCT dental care, such as graft-versus-host disease (GVHD) and the pediatric patient. It also aims to review pertinent subjects, both during the HSCT period and post-HSCT, concerning quality of life, pain, cost-effectiveness, and remote care. Based on this review, it is evident the importance of the work of the dental surgeon (DS) in the follow-up and treatment of the HSCT patient, always collaborating with the whole multidisciplinary team.

Mitochondria Transfer in Brain Injury and Disease

Intercellular mitochondria transfer is a novel form of cell signalling in which whole mitochondria are transferred between cells in order to enhance cellular functions or aid in the degradation of dysfunctional mitochondria. Recent studies have observed intercellular mitochondria transfer between glia and neurons in the brain, and mitochondrial transfer has emerged as a key neuroprotective mechanism in a range of neurological conditions. In particular, artificial mitochondria transfer has sparked widespread interest as a potential therapeutic strategy for brain disorders. In this review, we discuss the mechanisms and effects of intercellular mitochondria transfer in the brain. The role of mitochondrial transfer in neurological conditions, including neurodegenerative disease, brain injury, and neurodevelopmental disorders, is discussed as well as therapeutic strategies targeting mitochondria transfer in the brain.

Risk of oral cancer in patients with graft-vs-host disease: A systematic review and meta-analysis

OBJECTIVE

This systematic review was undertaken to determine the risk of oral cancer in patients with chronic graft-vs-host disease (cGvHD).

STUDY DESIGN

The search was conducted in 6 electronic databases (PubMed/MEDLINE, EMBASE, LILACS, Web of Science, Scopus, and LIVIVO) and gray literature (Google Scholar, Open Gray, and ProQuest) for studies published up to November 2021.

RESULTS

Of the 13 cohorts included in qualitative synthesis, 9 were eligible for the quantitative analysis. The meta-analysis showed that the presence of cGvHD increased the risk of developing oral cancer (risk ratio [RR] = 2.78; 95% CI, 1.27-6.08; I² = 46%; P = .01). A subgroup meta-analysis revealed a higher risk of oral cancer in Asian samples exposed to cGvHD (RR = 2.50; 95% CI, 1.54-4.04; I² = 0%; P = .0002), which was not seen in the pooled analysis of European samples (P = .24). The overall methodological quality of most studies included was "good." The cumulative evidence (Grading of Recommendations Assessment, Development and Evaluation) was considered moderate and of very low confidence for Asian and European studies, respectively.

CONCLUSIONS

Patients with cGvHD resulting from allogenic hematopoietic stem cell transplantation run an increased risk of developing oral cancer. Hence, it is recommended that patients with cGvHD be monitored to allow for the early detection and treatment of secondary malignant disease.

Mitomycin-Treated Endothelial and Smooth Muscle Cells Suitable for Safe Tissue Engineering Approaches

In our previous study, we showed that discarded cardiac tissue from the right atrial appendage and right ventricular myocardium is an available source of functional endothelial and smooth muscle cells for regenerative medicine and tissue engineering. In the study, we aimed to find out what benefits are given by vascular cells from cardiac explants used for seeding on vascular patches engrafted to repair vascular defects in vivo. Additionally, to make the application of these cells safer in regenerative medicine we tested an in vitro approach that arrested mitotic division to avoid the potential tumorigenic effect of dividing cells. A tissue-engineered construction in the form of a patch based on a polycaprolactone-gelatin scaffold and seeded with endothelial and smooth muscle cells was implanted into the abdominal aorta of immunodeficient SCID mice. Aortic patency was assessed using ultrasound, MRI, immunohistochemical and histological staining. Endothelial and smooth muscle cells were treated with mitomycin C at a therapeutic concentration of 10 μg/ml for 2 h with subsequent analysis of cell proliferation and function. The absence of the tumorigenic effect of mitomycin C-treated cells, as well as their angiogenic potential, was examined by injecting them into immunodeficient mice. Cell-containing patches engrafted in the abdominal aorta of immunodeficient mice form the vessel wall loaded with the appropriate cells and extracellular matrix, and do not interfere with normal patency. Endothelial and smooth muscle cells treated with mitomycin C show no tumorigenic effect in the SCID immunodeficient mouse model. During in vitro experiments, we have shown that treatment with mitomycin C does not lead to a decrease in cell viability. Despite the absence of proliferation, mitomycin C-treated vascular cells retain specific cell markers, produce specific extracellular matrix, and demonstrate the ability to stimulate angiogenesis in vivo. We pioneered an approach to arresting cell division with mitomycin C in endothelial and smooth muscle cells from cardiac explant, which prevents the risk of malignancy from dividing cells in vascular surgery. We believe that this approach to the fabrication of tissue-engineered constructs based on mitotically inactivated cells from waste postoperative material may be valuable to bring closer the development of safe cell products for regenerative medicine.

Facilitators and obstacles to couples' intimacy after hematopoietic stem cell transplantation: a qualitative study

To identify perceived factors related to intimacy following HSCT.

Qualitative descriptive design.

Patients diagnosed with hematological cancer, 6 months into their HSCT recovery, and their partners.

Semi-structured interviews were conducted with 18 participants (nine patients and their partners). A thematic analysis was carried out.

Couples reported various obstacles to intimacy, such as emotional obstacles (i.e. negative emotions, emotional mismatch), the length of the disease, its treatments and side effects, and the patient's physical condition. Couples also reported facilitators to intimacy, such as using emotional facilitators (e.g. showing empathy), fostering open communication or sharing common experience of the disease.

This study highlights specific factors that influence couples' intimacy in the context of HSCT.Implications for Psychosocial Providers: Couples' intervention delivered in cancer care should be adapted by focusing on specific factors that maintain or enhance couples' intimacy.

Long-term safety of photobiomodulation therapy for oral mucositis in hematopoietic cell transplantation patients: a 15-year retrospective study

Photobiomodulation therapy (PBMT) has demonstrated efficacy in the prevention and treatment of oral mucositis (OM) in hematopoietic cell transplantation (HCT). However, based on the cell stimulation properties, its long-term safety has been questioned, mainly in relation to risk for secondary malignancies in the oral cavity. The aim of this study was to investigate if different PBMT protocols for OM control have association with immediate and late adverse effects in HCT patients. Data on autologous and allogeneic transplantation, conditioning regimen, PBMT protocols, and OM severity were retrospectively collected from medical and dental records. Presence of secondary malignancies in the oral cavity was surveyed during a 15-year follow-up. Impact of OM on overall survival was also analyzed. Different PBMT protocols for prevention and treatment of OM were recorded over the years. Severe OM (grades 3 and 4) was infrequently observed. When present, we observed a significant decrease of the overall survival. No immediate adverse effect and secondary malignancy was associated to PBMT. In conclusion, the PBMT protocols used in the study were considered safe. The low frequency of severe OM observed encourages the implementation of this technique, with a special emphasis on the dosimetry adjustments focused on the HCT context.

Label-free on chip quality assessment of cellular blood products using real-time deformability cytometry

Without cellular blood products such as platelet concentrates (PC), red blood cell concentrates (RCC), and hematopoietic stem cells (HPSC) modern treatments in medicine would not be possible. An unresolved challenge is the assessment of their quality with minimal cell manipulation. Minor changes in production, storage conditions, or blood bag composition may impact cell function, which can have important consequences on product integrity. This is especially relevant for personalized medicine, such as autologous T-cell therapy. Today a robust methodology that globally determines cell status directly before transfusion or transplantation is lacking. We demonstrate that measuring viscoelastic characteristics of peripheral blood cells using real-time deformability cytometry (RT-DC) provides comprehensive information on product quality, which is not accessible using conventional quality control tests. In addition, RT-DC requires few cells, a minimal sample volume and has a rapid turnaround time. We compared RT-DC to standard in vitro quality assays assessing: i) PC after storage at 4 °C and room temperature; ii) magnetic nanoparticle labeled platelets; iii) RCC stored in blood bags with different plasticizers; iv) RCC after gamma irradiation; and v) HPSC after cryopreservation with 5% or 10% dimethyl sulfoxide, respectively. Additionally, we evaluated the engraftment time of patients' platelets and leukocytes after transplantation of HPSC products. Our results demonstrate that label-free mechano-phenotyping can be used as a potential biomarker for quality assessment of cell-based pharmaceutical products.