Milk lactoperoxidase decreases ID1 and ID3 expression in human oral squamous cell carcinoma cell lines

Reinhard Gruber,Theresa Sophia Bokor,Maria De Biasi,Alexandra Thajer,Layla Panahipour,Nadja Haiden

doi:10.1038/s41598-020-62390-4

Reinhard Gruber, Theresa Sophia Bokor + Show 4 more

Open Access

https://doi.org/10.1038/s41598-020-62390-4

Copy DOI

Abstract

Milk consumption may modify the risk of squamous cell carcinoma. The role of milk to modulate the gene expression in oral squamous cell carcinoma cells has not been investigated so far. Here, HSC2 oral squamous carcinoma cells were exposed to an aqueous fraction of human milk and a whole-genome array was performed. Among the genes that were significantly reduced by human and cow milk were the DNA-binding protein inhibitor 1 (ID1), ID3 and Distal-Less Homeobox 2 (DLX2) in HSC2 cells. Also, in TR146 oral squamous carcinoma cells, there was a tendency towards a decreased gene expression. Upon size fractionation, lactoperoxidase but not lactoferrin and osteopontin was identified to reduce ID1 and ID3 in HSC2 cells. Dairy products and hypoallergenic infant formula failed to decrease the respective genes. These data suggest that milk can reduce the expression of transcription factors in oral squamous carcinoma cells.

Highlights

Milk consumption may modify the risk of squamous cell carcinoma
We have previously shown that milk holds an anti-inflammatory activity for cells of the oral cavity including gingival fibroblasts, macrophages and the squamous cell carcinoma cell line HSC219
Western blot analysis revealed that after 72 hours of exposure of HSC2 cells, the aqueous fractions of human milk, cow milk and infant formula decreased the levels of ID1 and ID3 on the protein level

Summary

Results

Gene array of HSC2 cells exposed to human milk. To reveal the spectrum of strongly regulated genes, HSC2 cells were exposed to 5% of an aqueous fraction of pooled pasteurized human milk and a gene array was performed. Neither of the dairy products – yogurt, buttermilk, sour milk and whey - provoked considerable changes of ID1, ID3 and DLX2 expression (Suppl Fig. 2) In support of these observations, lowering the pH in pasteurized cow milk by adding 2% of lactic acid almost abolished the activity of the corresponding aqueous fraction (Suppl Fig. 3). Western blot analysis revealed that after 72 hours of exposure of HSC2 cells, the aqueous fractions of human milk, cow milk and infant formula decreased the levels of ID1 and ID3 on the protein level. Exposure of HSC2 to SB431542 failed to reverse the activity of human milk to decrease the target genes in HSC2 cells (Fig. 5) In support of these findings, recombinant TGF-β1 had no impact on gene expression (data not shown). To some extent, MAPK can mediate the effects of milk to decreases ID1, ID3 and DLX2 in HSC2 cells

Discussion

Findings

Material and Methods