Study drug responses with exceptional
predictive value

The power lies in the matrix!

Monolayer vs 3D Cell Culture in LunaGel™

LunaGel™ ECM facilitates drug-response studies that are highly predictive of the in vivo situation. Below is an example of MCF-7 breast cancer spheroids subjected to a chemotherapeutic agent (Abraxane/human serum albumin-conjugated paclitaxel). While Abraxane treatment led to almost complete loss of viability in monolayer cultures, the metabolic response and viability of MCF-7 cells, a cell line derived from non-metastatic breast tumours, was more similar to in vivo responses when cultured in LunaGel™. Interestingly, Abraxane treatment of metastatic MDA-MB-231 breast cancer cells led to a substantially larger decrease in metabolic activity and viability, as well as a loss of metastatic cellular morphologies.

The difference in cell response between MCF-7 and MDA-MB-231 cells may be related to the variances in growth and migration patterns. MCF-7 cells form tumour-like spheroids which may hinder the penetration of the drug to the cells in the spheroid core. MDA-MB-231, on the other hand, are metastatic and highly migratory, and hence often exist as single cells rather than cell clusters, in turn leading to higher drug efficiencies. Indeed, this finding is corroborated by clinical studies which clearly demonstrate more effective treatment of metastatic cancers with Abraxane compared to primary tumours, ultimately leading to the admission of Abraxane for metastatic breast cancer treatment. Ultimately, this data demonstrates the benefits of using LunaGel™ 3D assays over traditional monolayer cultures, which incorrectly predicted a high efficiency of Abraxane treatment on both, MCF-7 and MDA-MB-231 cells.

Response of MCF-7 and MDA-MB-231 breast cancer cells to Abraxane treatment.

Relative metabolic rate of (A) MCF-7 and (E) MDA-MB-231 breast cancer cells encapsulated in LunaGel™ and monolayer cultures following 3 days of treatment with varying concentrations of Abraxane (metabolic response of treated groups was normalised to untreated controls). Viability and spheroid/cell morphology of (B) MCF-7 and (F) MDA-MB-231 cells in untreated cultures (control) and following treatment with 300 ppm Abraxane for 3 days. Quantification of (C) relative integrated fluorescence intensities (live/dead) and (D) spheroid size revealed cytotoxic effects of Abraxane treatment in embedded MCF-7 and MDA-MB-231 cultures. (G) Treatment of MDA-MB-231 cells reduced cell viability by > 50% compared to controls.

50 Determination of IC Values of Anticancer Drugs

The IC50 is a quantitative measure that indicates how much of a particular inhibitory substance (e.g. drug) is needed to inhibit a given biological process or biological component by 50%. In this study, our collaborators have used automated liquid handling to produce LunaGel™ 3D cell culture samples with MDA-MB-231 breast cancer cells. The effect of paclitaxel, a chemotherapeutic agent, was studied using high-throughput screening approaches used in pharmaceutical industry. The ability to use LunaGel™ with high-throughput techniques is a clear advantage over traditional 3D cell culture platforms like basement membrane extracts.

Determination of the IC50 of paclitaxel against metastatic breast cancer cells encapsulated in LunaGel™

MDA-MB-231 breast cancer cells were cultured in LunaGel (5 kPa) for 7 days, and incubated with different concentrations of paclitaxel for 120 h. Metabolic activity was assessed using automated oxygen consumption measurements.

Investigating the effects of IGF-I:IGFBP-3:VN trimeric complexes on melanoma spheroid growth

Insulin-like growth factor 1 (IGF-1) binds to the extracellular matrix protein vitronectin (VN) through IGF binding proteins (IGFBPs) to enhance proliferation of skin keratinocytes and fibroblasts. However, the role of this trimeric complex (TRI) in melanoma progression remains largely unknown. The figure below shows the formation of irregular spheroids by SK-MEL-28 cells in basement membrane extract with a trend towards increased spheroid sizes with higher concentration of TRI. In LunaGel™, the effects were more pronounced - cells formed regular, easy to quantify, spheroids which increased significantly in size with increasing concentrations of TRI, revealing a stimulating effect of TRI on melanoma growth.

BME

IGF-1:IGFBP-3:VN (TRI) complex stimulates the growth of melanoma spheroids in LunaGel™ ECM.

SK-MEL-28 cells were seeded onto basement membrane extracts (BME) or encapsulated in LunaGel™ (5 kPa). On day 14, cells were stained with FDA for visualisation and spheroid size assessment. TRI 30 = 1 ng/mL VN + 30 ng/mL IGF-I + 90 ng/mL IGFBP-3; TRI 100 = 1 ug/mL VN + 100 ng/mL IGF-I + 300 ng/mL IGFBP-3; TRI 300 = 1 μg/mL VN + 300 ng/mL IGF-I + 900 ng/mL IGFBP-3. n = 6 (2 technical repeats, 3 experimental repeats); # p < 0.05 compared to 2% FCS, #### p < 0.0001 compared to 2% FCS; **** p < 0.0001.