Sponge-supported cultures of primary head and neck tumors for an optimized preclinical model

Abstract

Treatment of advanced head and neck cancer is associated with low survival, high toxicity and a widely divergent individual response. The sponge-gel-supported histoculture model was previously developed to serve as a preclinical model for predicting individual treatment responses. We aimed to optimize the sponge-gel-supported histoculture model and provide more insight in cell specific behaviour by evaluating the tumor and its microenvironment using immunohistochemistry. We collected fresh tumor biopsies from 72 untreated patients and cultured them for 7 days. Biopsies from 57 patients (79%) were successfully cultured and 1451 tumor fragments (95.4%) were evaluated. Fragments were scored for percentage of tumor, tumor viability and proliferation, EGF-receptor expression and presence of T-cells and macrophages. Median tumor percentage increased from 53% at day 0 to 80% at day 7. Viability and proliferation decreased after 7 days, from 90% to 30% and from 30% to 10%, respectively. Addition of EGF, folic acid and hydrocortisone can lead to improved viability and proliferation, however this was not systematically observed. No patient subgroup could be identified with higher culture success rates. Immune cells were still present at day 7, illustrating that the tumor microenvironment is sustained. EGF supplementation did not increase viability and proliferation in patients overexpressing EGF-Receptor.

Making In Vitro Tumor Models Whole Again

“…By using gelatin sponges to support ex vivo slice culture of primary HNSCC, Dohmen et al observed that T cells and macrophages were preserved during 7 days of culture, although significant changes in the proportion of subpopulations occurred. [36] In another study, Jiang et al established a PDE culture system that allowed slices derived from PDAC to freely float on collagen-coated inserts; this approach yielded stable preservation of T cell-and macrophage-specific markers over 6 days. [66] In a recent study, Voabil et al took a step further, where PDEs were shown to not only preserve the composition of immune cells, but also retained cell function (secretion of chemokines and cytokines) at the end of a 2-day culture period.…”

Precision Medicine Gains Momentum: Novel 3D Models and Stem Cell-Based Approaches in Head and Neck Cancer

“…Although it was unclear whether they were still functionally active or viable, based on the morphology the authors believe the immune cells to keep their viability up to day 7. The authors hope that the histoculture model, which comes closer to reality than cell lines or even organoids due the preservation of the heterogeneity and TME may allow for personalized treatment stratification and testing for new treatment strategies in the future ( Dohmen et al, 2018 ).…”

“…Although these data appear promising, there are various reasons why the HDRA is not taken into routine clinical practice such as the requirement of an in-hospital laboratory to ensure the quick processing of fresh biopsies, large effort of time and personnel and last the lack of sensitivity and specificity when correlating in vivo tumor response to in vitro HDRA chemosensitivity ( Dohmen et al, 2018 ).…”

Model Selection for the Preclinical Development of New Drug–Radiotherapy Combinations

“…Freshly resected tumour tissue is typically either diced into small fragments [46,77,82e84] or sliced using a vibratome [46,83,85e88]. The tissue is either supported by a membrane insert [46,82,83,85e88] or a collagen sponge [46,77,83,84], which helps to preserve tissue structure and prolong the survival of stromal cells [83]. Majumder et al [89] investigated even further complex growth substrates, reporting that grade-matched tumourstromal matrix proteins conserved baseline tumour tissue characteristics more effectively than mismatched tumourstromal matrix proteins.…”