image: Cell counting and invasion assays after DBP-upregulation. (A) Cell counting at 0, 24, 48, and 72 hrs. after DBP overexpression compared to empty vector used as a control, a significantly lower cell count noted at 48 and 72 hrs. (*p < 0.05; **p < 0.01; ***p < 0.001), respectively. (B) A significantly lower invasion is shown after DBP-overexpression compared to empty vector at 72 hrs. (***p < 0.001).
Oncotarget published "Differential expression of Vitamin D binding protein in thyroid cancer health disparities" which reported that thyroid cancer incidence, recurrence, and death rates are higher among Filipino Americans than European Americans.
In this study, the authors determined the correlation between differential DBP expression in tumor tissues and cancer staging in Filipino Americans versus European Americans.
The majority of Filipino Americans presented with advanced tumor staging. In contrast, European Americans showed early staging and very few advanced tumors.
On the contrary, in the tumor tissues derived from European Americans, moderate to strong DBP staining was detected and correlated to early staging. When downregulation of the DBP gene in papillary thyroid cancer cell lines was observed, tumor proliferation and migration were enhanced.
The Oncotarget Authors determined a differential expression of an essential biological molecule is linked to cancer staging in thyroid cancer health disparities in two ethnicities.
Dr. Salma Khan from The Loma Linda University School of Medicine said, "Thyroid cancer is one of the most prevalent endocrine cancers."
"Thyroid cancer is one of the most prevalent endocrine cancers."
They identified a highly polymorphic protein, called vitamin D binding protein that could play an important role in thyroid cancer progression in ethnically predisposed group.
Although DBP has both vitamin D-dependent/independent roles in cancer development, vitamin D-dependent DBP functions in cancer are well studied with inconclusive results.
Therefore, they tested whether DBP has the ">vitamin D-independent correlations/functions to thyroid cancer oncogenesis.
Although DBP is an essential protein with multifunctional properties, very few studies are available on its contribution to thyroid cancer oncogenesis.
In the present study, they determined the differential expression of DBP protein in the thyroid cancer tissues and correlated it to cancer staging in Filipino Americans compared to European Americans.
The Khan Research Team concluded in their Oncotarget Research Output, "we demonstrate that the presence or absence of DBP inversely correlates to thyroid cancer staging in two ethnicities. We report that most Filipino Americans presented with advanced thyroid cancer and showed low to no DBP expression. In contrast, European Americans with early stage PTC, showed a moderate to strong DBP expression, supporting the protective roles of DBP in the tumor microenvironment, independent of vitamin D. Our in vitro study details the functional consequences of loss-of/gain-in-DBP-function in thyroid cancer oncogenesis. We conclude that the gain/loss of DBP may stimulate immune-modulated signaling pathways in thyroid cancer health disparities, which awaits further investigation."