Wheat Bran Polymer Scaffolds: Supporting Triple-Negative Breast Cancer Cell Growth and Development

Abstract

Arabinoxylans (AX) are functional biopolymers, the main non-starch polysaccharides in cereals and other plants. AX is composed of xylose and arabinose, and the ester-linkage of ferulic acid to arabinose confers its bioactive properties. The backbone of AX resembles that of glycosaminoglycans, a major component of the human extracellular matrix. This study explores the potential of wheat bran AX-based scaffolds as a novel platform for the growth and development of triple-negative breast cancer (TNBC) cells, an aggressive form of breast cancer. Importantly, patients face the worst prognosis due to the stemness of the TNBC cells and the formation of hypoxic cell clumps. Wheat bran constitutes 15-25% of the byproducts after milling and adds limited economic value. We have extracted AX from wheat bran (WBAX) and developed soft scaffolds with Na-alginate. The scaffolds were seeded with the triple-negative breast cancer cell line MDA-MB-231. Over 21 days, cell growth and development, cell migration within the hydrogels, and the formation of hypoxic regions within cell clumps were observed. These findings suggest that WBAX-based scaffolds provide a conducive environment for TNBC cell proliferation and development, offering a promising avenue for further research into cancer cell biology and potential therapeutic applications.

Keywords: MDA-MB-231 cell lines; arabinoxylan; breast cancer; hypoxia; scaffolds; spheroid; wheat bran.

Figure 1

Extraction pathway of Arabinoxylan (AX) from wheat bran leading to AX [31].

Figure 2

Gel mechanics (panel (A)) Modulus in MPa, (panel (B)) Hardness in MPa. A. (WBAX: SA 1:2); B. (SBAX: SA 1:2); C. (WBAX: SA: C 1:2:1); D. (SBAX: SA: C 1:2:1).

Figure 3

The water holding capacity of hydrogel. The columns represent dry weight, weight after soaking the dry components in water, and water holding capacity.

Figure 4

SYBR green-labeled MD MB 231 live cells and propidium-labeled dead cells after 5 days. (A). Live and dead MDA-MB-231 cells overlayed in control (no hydrogel). (B). Live and dead cells overlayed in hydrogel. The cells were of fibroblastic morphology, which is normal for that culture environment. (100 µm).

Figure 5

Comparison of the ratio of live and dead cells in the control (no hydrogel) and the hydrogel. n.s. is not significant.

Figure 6

(A). Bright field image of MD MB 231. (B). Cells in different hydrogel planes. (B1). Focus on the monolayer of the bottom surface. (B2). Focus on approximately 370 microns above the bottom surface. (C). Hypoxia Region in the spheroid. Blue represents DAPI fluorescence, green represents SYBR green fluorescence, and red represents the propidium fluorescence.

Figure 7

Confocal images of MDA-MB-231 cells grown in media (left) and a 1:2 WBAX to SA mixture (right) after 21 days. DAPI signaling (blue) indicates the nucleus of the cells, while Hypoxia dye (green) indicates the absence of oxygen. Objective data were collected and compared with each other (n = 3). (A). MDA-MB-231 cells grown in control well (media only) (B). MDA-MB-231 cells grown in experimental well WBAX and SA (2:1) (C). Significant difference p < 0.1 in hypoxia-specific dye intensity.