Calcium Channel Subunit Alpha2delta 2 Is Upregulated During Odontoblast-Like Differentiation and Exhibits Higher...

Recent work in Lebanese families with familial non‑syndromic tooth agenesis identified calcium voltage‑gated channel auxiliary subunit alpha2delta 2 (CACNA2D2) and triple functional domain protein (TRIO) as candidate genes, and a subsequent computational study linked both to an odontogenesis‑relevant signaling framework. However, it remains unclear whether CACNA2D2 and TRIO are expressed in human dental stem cells and whether their transcript levels change during odontogenic induction.

Dental pulp stem cells (DPSCs) and stem cells from human exfoliated deciduous teeth (SHED) were cultured under standard mesenchymal stem cell conditions, and DPSCs were exposed to odontogenic medium for 21 days to generate odontoblast‑like cells. Total ribonucleic acid (RNA) was extracted from undifferentiated DPSCs, differentiated odontoblast‑like cells, and undifferentiated SHED, and CACNA2D2 and TRIO expression was evaluated by semi‑quantitative reverse transcription polymerase chain reaction (RT‑PCR) with glyceraldehyde‑3‑phosphate dehydrogenase (GAPDH) normalization and ImageJ‑based densitometry in five independent biological replicates. Pairwise group comparisons were analyzed using the two‑tailed Student's t‑test.

CACNA2D2 expression was higher in odontoblast‑like cells than in undifferentiated DPSCs, with semi‑quantitative densitometry indicating an approximate threefold increase (two‑tailed Student's t‑test, t(8) = 3.21, p = 0.016). Basal CACNA2D2 expression was also higher in SHED than in DPSCs, with an approximate sevenfold difference (t(8) = 4.50, p = 0.001). In contrast, TRIO expression did not differ significantly between groups (t(8) = 0.84, p = 0.42, and t(8) = 0.67, p = 0.52).

CACNA2D2, but not TRIO, showed differentiation‑associated and cell‑type‑dependent transcriptional variation in human dental pulp‑derived stem cell models under odontogenic induction conditions. These findings provide preliminary semi‑quantitative wet‑laboratory support for CACNA2D2 as a gene of interest in human odontogenesis and familial tooth agenesis but remain correlative and should be confirmed by quantitative reverse transcription polymerase chain reaction (RT‑qPCR), canonical odontogenic differentiation markers, mineralization assays, and functional studies in the same experimental system.