Novel human lymph node-derived matrix supports the adhesion of metastatic oral carcinoma cells.

BACKGROUND: 3D culture is increasingly used in cancer research, as it allows the growth of cells in an environment that mimics in vivo conditions. Metastases are the primary cause of morbidity and mortality in cancer patients, and solid tumour metastases are mostly located in lymph nodes. Currently, there are no techniques that model the pre-metastatic lymph node microenvironment in vitro. In this study, we prepared a novel extracellular matrix, Lymphogel, which is derived from lymph nodes, mimicking the tumour microenvironment (TME) of metastatic carcinoma cells. We tested the suitability of the new matrix in various functional experiments and compared the results with those obtained using existing matrices. METHODS: We used both commercial and patient-derived primary and metastatic oral tongue squamous cell carcinoma (OTSCC) cell lines. We characterized the functional differences of these cells using three different matrices (human uterine leiomyoma-derived Myogel, human pre-metastatic neck lymph node-derived Lymphogel (h-LG), porcine normal neck lymph node-derived Lymphogel (p-LG) in proliferation, adhesion, migration and invasion assays. We also performed proteomic analyses to compare the different matrices in relation to their functional properties. RESULTS: OTSCC cells exhibited different adhesion and invasion patterns depending on the matrix. Metastatic cell lines showed improved ability to adhere to h-LG, but the effects of the matrices on cell invasion fluctuated non-significantly between the cell lines. Proteomic analyses showed that the protein composition between matrices was highly variable; Myogel contained 618, p-LG 1823 and h-LG 1520 different proteins. The comparison of all three matrices revealed only 120 common proteins. Analysis of cellular pathways and processes associated with proteomes of each matrix revealed similarities of Myogel with h-LG but less with p-LG. Similarly, p-LG contained the least adhesion-related proteins compared with Myogel and h-LG. The highest number of unique adhesion-related proteins was present in h-LG. CONCLUSIONS: We demonstrated that human pre-metastatic neck lymph node-derived matrix is suitable for studying metastatic OTSCC cells. As a whole-protein extract, h-LG provides new opportunities for in vitro carcinoma cell culture experiments.

Human Tumor-Derived Matrix Improves the Predictability of Head and Neck Cancer Drug Testing.

In vitro cancer drug testing carries a low predictive value. We developed the human leiomyoma-derived matrix "Myogel" to better mimic the human tumor microenvironment (TME). We hypothesized that Myogel could provide an appropriate microenvironment for cancer cells, thereby allowing more in vivo-relevant drug testing. We screened 19 anticancer compounds, targeting the epidermal growth factor receptor (EGFR), MEK, and PI3K/mTOR on 12 head and neck squamous cell carcinoma (HNSCC) cell lines cultured on plastic, mouse sarcoma-derived Matrigel (MSDM), and Myogel. We applied a high-throughput drug screening assay under five different culturing conditions: cells in two-dimensional (2D) plastic wells and on top or embedded in Matrigel or Myogel. We then compared the efficacy of the anticancer compounds to the response rates of 19 HNSCC monotherapy clinical trials. Cancer cells on top of Myogel responded less to EGFR and MEK inhibitors compared to cells cultured on plastic or Matrigel. However, we found a similar response to the PI3K/mTOR inhibitors under all culturing conditions. Cells grown on Myogel more closely resembled the response rates reported in EGFR-inhibitor monotherapy clinical trials. Our findings suggest that a human tumor matrix improves the predictability of in vitro anticancer drug testing compared to current 2D and MSDM methods.