Family with sequence similarity 172, member A (FAM172A), was cloned from human aortic tissues and confirmed in our previous study in 2009, however, its functions remain to be fully elucidated. In our previous studies, the
protein expression of FAM172A in human aortic smooth muscle cells was found to be upregulated by high
glucose in a concentration‑ and time‑dependent manner. Several reports have shown that
insulin resistance is associated with
papillary thyroid carcinoma (PTC). Thus, in the present study, the
protein expression levels of FAM172A in human
papillary thyroid carcinoma were investigated, and the effect of the FAM172A
protein on the proliferation of IHH‑4 human
papillary thyroid carcinoma cells, and its potential molecular underlying mechanisms were examined. Immunohistochemistry and western blotting demonstrated that the
protein expression of FAM172A in
papillary thyroid carcinoma tissues was not only significantly higher than that in noncancerous tissues adjacent to the
carcinoma tissues, but it was also markedly higher than that in normal thyroid and
thyroid adenoma tissues. Overexpression of the FAM172A
protein activated the
p38 MAPK pathway, but not the PI3K and AMPK pathways, in the IHH‑4 cells. In addition, overexpression of the FAM172A
protein accelerated IHH‑4 cell proliferation, compared with the control group, and the pro‑proliferative effect of FAM172A
protein on IHH4 cells was markedly attenuated by
SB202190, an inhibitor of
p38 MAPK. Taken together, these results suggest that the FAM172A
protein is expressed at high levels in human PTC, which may promote cell proliferation via activation of the
p38 MAPK signaling pathway, and be involved in the pathogenesis of PTC.