Noel Ye Naung

Liquid biopsies promise major advantages for cancer screening and diagnosis. By detecting biomarkers in peripheral blood samples, liquid biopsies reduce the need for invasive techniques and provide important genetic information integral to the emerging molecular classification of cancers. Unfortunately, the concentrations of most biomarkers, particularly circulating tumour nucleic acids, are vanishingly small—beyond the sensitivity and specificity of most assays. Clustered Regularly Interspaced Short Palindromic Repeats diagnostics (herein labelled ‘CRISPR-Dx’) use gene editing tools to detect, rather than modify, nucleic acids with extremely high specificity. These tools are commonly combined with isothermal nucleic acid amplification to also achieve sensitivities comparable to high-performance laboratory-based techniques, such as digital PCR. CRISPR assays, however, are inherently well suited to adaptation for point-of-care (POC) use, and unlike antigen-based POC assays, are significantly easier and faster to develop. In this review, we summarise current CRISPR-Dx platforms and their analytical potential for cancer biomarker discovery, with an emphasis on enhancing early diagnosis, disease monitoring, point-of-care testing, and supporting cancer therapy.

When clear aligners and veneers are used preoperatively, placement of orthodontic brackets is not possible. The MatrixWAVE maxillomandibular fixation (MMF) screws are readily available in many operating rooms and can be used as an alternative interim fixation device. Screws from this system can be left in place for postoperative elastic physiotherapy. In this case report, MMF screws were left in place for muscle memory training and an aid to prevent relapse. The screws were well tolerated by the patient. Removal at 14 weeks resulted in small wounds, which healed quickly.

Harvesting, expanding, and re‐implanting osteogenic mesenchymal stem cells (MSCs) avoids the donor‐site morbidity associated with autogenous grafting from bone marrow. Mesenchymal stem cells sourced from the palatal periosteum could be an alternative to isolation of such cells using bone marrow aspiration procedures. For safe use in human therapy, MSCs should be expanded in culture medium that is free from animal or human‐derived serum. In this study we localized, quantified, and characterized MSCs from palatal periosteum cultured in serum‐free, xeno‐free Essential 8 medium. A portion of the palatal periosteum tissues from three patients were dual‐immunostained with MSC‐specific markers (CD105, CD90, and CD73). The remaining portions were expanded in culture, and the isolated MSCs were analyzed using flow cytometry and tri‐lineage differentiation. Palatal periosteum sections were found to contain CD105‐, CD90‐, and CD73‐positive cells. The cultured cells were 73.0 ± 6.7% (mean ± SD) positive for all three MSC‐specific markers and were without hematopoietic stem cell (HSC) markers 0.5 ± 0.3% (mean ± SD). Tri‐lineage differentiation analysis confirmed that palatal periosteum cells could become adipoblasts, chondroblasts, and osteoblasts. The results demonstrate that palatal‐derived MSCs could be detected in situ within small niches, and when expanded in serum‐free, xeno‐free medium represent a viable source of MSCs for clinical use.