TY  - JOUR
AU  - Tuba, Syahrul
AU  - Sakdiyyah, Luluk
AU  - Panjaitan, Natanael
AU  - Pradana, F. Josse Pasca
AU  - Priyono, Adi
AU  - Sumaryono, Budi
PY  - 2026
DA  - 2026/09/21
TI  - Integrating Germline and Somatic Pharmacogenomics to Predict Tamoxifen Response in Breast Cancer
JO  - OBM Genetics
SP  - 359
VL  - 10
IS  - 03
AB  - Tamoxifen remains a cornerstone in the treatment of estrogen receptor-positive (ER+) breast cancer; however, variability in patient response underscores the necessity of a pharmacogenomic approach. This review integrates germline and somatic pharmacogenomics to elucidate the molecular determinants of tamoxifen metabolism, efficacy, and resistance. Germline polymorphisms, particularly in CYP2D6, CYP3A4/5, UGT2B7, and SULT1A1, significantly influence endoxifen levels, driving therapeutic variability across ethnic populations. Moreover, somatic mutations, notably in ESR1, TP53, and enhancer regions, confer acquired resistance and affect treatment outcomes. Ethnicity-specific distributions of these variants further highlight the inadequacy of a one-size-fits-all dosing strategy. Although CPIC and DPWG guidelines focus on CYP2D6 genotyping, they do not incorporate critical somatic data and phase II metabolism. To achieve truly personalized tamoxifen therapy, clinical algorithms must evolve to integrate germline and somatic profiles, enabling predictive, population-aware, and mutation-guided endocrine treatment. This review advocates for expanded multi-omics frameworks and multiethnic databases to optimize tamoxifen use and overcome endocrine resistance globally.
SN  - 2577-5790
UR  - https://doi.org/10.21926/obm.genet.2603359
DO  - 10.21926/obm.genet.2603359
ID  - Tuba2026
ER  -