Patient-derived head and neck cancer organoids allow treatment stratification and serve as a tool for biomarker validation and identification

BACKGROUND

Organoids are in vitro three-dimensional structures that can be grown from patient tissue. Head and neck cancer (HNC) is a collective term used for multiple tumor types including squamous cell carcinomas and salivary gland adenocarcinomas.

METHODS

Organoids were established from HNC patient tumor tissue and characterized using immunohistochemistry and DNA sequencing. Organoids were exposed to chemo- and radiotherapy and a panel of targeted agents. Organoid response was correlated with patient clinical response. CRISPR-Cas9-based gene editing of organoids was applied for biomarker validation.

FINDINGS

A HNC biobank consisting of 110 models, including 65 tumor models, was generated. Organoids retained DNA alterations found in HNC. Comparison of organoid and patient response to radiotherapy (primary [n = 6] and adjuvant [n = 15]) indicated potential for guiding treatment options in the adjuvant setting. In organoids, the radio-sensitizing potential of cisplatin and carboplatin could be validated. However, cetuximab conveyed radioprotection in most models. HNC-targeted treatments were tested on 31 models, indicating possible novel treatment options with the potential for treatment stratification in the future. Activating PIK3CA mutations did not predict alpelisib response in organoids. Protein arginine methyltransferase 5 (PRMT5) inhibitors were identified as a potential treatment option for cyclin-dependent kinase inhibitor 2A (CDKN2A) null HNC.

CONCLUSIONS

Organoids hold potential as a diagnostic tool in personalized medicine for HNC. In vitro organoid response to radiotherapy (RT) showed a trend that mimics clinical response, indicating the predictive potential of patient-derived organoids. Moreover, organoids could be used for biomarker discovery and validation.

FUNDING

This work was funded by Oncode PoC 2018-P0003.

Troy/Tnfrsf19 marks epidermal cells that govern interfollicular epidermal renewal and cornification

The skin epidermis is a highly compartmentalized tissue consisting of a cornifying epithelium called the interfollicular epidermis (IFE) and associated hair follicles (HFs). Several stem cell populations have been described that mark specific compartments in the skin but none of them is specific to the IFE. Here, we identify Troy as a marker of IFE and HF infundibulum basal layer cells in developing and adult human and mouse epidermis. Genetic lineage-tracing experiments demonstrate that Troy-expressing basal cells contribute to long-term renewal of all layers of the cornifying epithelium. Single-cell transcriptomics and organoid assays of Troy-expressing cells, as well as their progeny, confirmed stem cell identity as well as the ability to generate differentiating daughter cells. In conclusion, we define Troy as a marker of epidermal basal cells that govern interfollicular epidermal renewal and cornification.

Perspective on digital mammography

Digital mammography, particularly through its advanced applications, holds great promise for improved diagnostic accuracy, but the display of the images is not ideal at present. Clinical softcopy workstations are somewhat unwieldy to use, and image processing has not yet been optimized for each machine or for each clinical task. In addition, the cost-effectiveness and accuracy of the technology warrant careful study before digital mammography becomes widely disseminated and potentially replaces screen-film mammography, a technology that has been well documented to reduce breast cancer mortality.

What every surgical oncologist should know about digital mammography

This article reviews the available information on digital mammography for surgeons who care for patients with breast cancer. The limitations of the current film-based technology and why digital mammography promises to improve breast cancer detection and breast lesion diagnosis are described. The basics of digital imaging technology are reviewed, including a description of image contrast and spatial resolution and its variance from currently available clinical digital mammography systems. The results of clinical trials completed to date are reported. An upcoming large screening trial for digital mammography, sponsored by the National Cancer Institute, is described. Future technological developments, including improvements in softcopy display, image processing, computer-aided detection and diagnosis (CADD), tomosynthesis, and digital subtraction mammography (DSM), are briefly discussed.

Placental transmogrification of the lung, a histologic variant of giant bullous emphysema. Clinicopathological study of three further cases

Placental transmogrification of the lung was described by Chesney in 1978 as an unusual cystic lesion involving a single pulmonary lobe (3). We studied three additional cases with identical clinical and pathologic features. The patients were a 33-year-old woman and men aged 24 and 27 years. Each patient was first seen with respiratory distress; one had repeated pneumothoraces. Radiographically, an enlarging cystic lesion was present in a lower (two) or middle (one) lobe. The lesion had been present for 10 years in one patient. In two patients, mediastinal shift was noted. Lobectomy was curative in all instances. Grossly there was a uni- or paucilocular cyst lined by papillary structures. Microscopically, the papillae contained proliferating blood vessels, lymphoid nodules, smooth muscle, and fat. Sclerotic foci obliterated the vessels in some areas. The growth pattern and topography resembled those of placental villi. Systematic review of the histologic features in other lungs with marked emphysema revealed a spectrum of similar changes and suggested that the lesion in our patients may be a complication of bulla formation and is most likely the clinico-pathologic analog of the "vanishing lung" syndrome (idiopathic giant bullous emphysema).