DKK1 and gastroesophageal junction adenocarcinoma: The validated assay is being applied to prospectively identify G/GEJ adenocarcinoma second-line patients with high tumoral expression of DKK1 for a phase 2 clinical trial in combination with DKN-01 and the anti-PD-1 therapeutic, tislelizumab, and as a retrospective analysis of first-line patients treated with DKN-01 in combination with tislelizumab and chemotherapy (NCT04363801).