Departamento de Biología de la Reproducción, Dr. Carlos Gual Castro, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Av. Vasco de Quiroga No. 15, Belisario Domínguez Sección XVI, Tlalpan 14080, Ciudad de México, Mexico; Programa de Doctorado en Ciencias Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México, Mexico.
Departamento de Biología de la Reproducción, Dr. Carlos Gual Castro, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Av. Vasco de Quiroga No. 15, Belisario Domínguez Sección XVI, Tlalpan 14080, Ciudad de México, Mexico.
J Steroid Biochem Mol Biol. 2022 Oct;223:106132. doi: 10.1016/j.jsbmb.2022.106132. Epub 2022 May 31.
Fibroblast growth factor receptor (FGFR) overamplification/activation in cancer leads to increased cell proliferation. AZD4547, a FGFR selective inhibitor, hinders breast cancer cells growth. Although luminal B breast tumors may respond to chemotherapy and endocrine therapy, this subtype is associated with poor prognosis, inadequate response and/or acquired drug resistance. Calcitriol, the vitamin D most active metabolite, exerts anti-neoplastic effects and enhances chemotherapeutic drugs activity. In this study, we sought to decrease the concentration of AZD4547 needed to inhibit the luminal-B breast cancer cell line BT-474 proliferation by its combination with calcitriol. Anti-proliferative inhibitory concentrations, combination index and dose-reduction index were analyzed from Sulforhodamine B assays. Western blot and qPCR were used to study FGFR molecular targets. The compound's ability to inhibit BT-474 cells tumorigenic capacity was assessed by tumorspheres formation. Results: BT-474 cells were dose-dependently growth-inhibited by calcitriol and AZD4547 (IC = 2.9 nM and 3.08 μM, respectively). Calcitriol at 1 nM synergistically improved AZD4547 antiproliferative effects, allowing a 2-fold AZD4547 dose-reduction. Mechanistically, AZD4547 downregulated p-FGFR1, p-Akt and tumorsphere formation. Calcitriol also decreased tumorspheres, while induced cell differentiation. Both compounds inhibited MYC and CCND1 expression, as well as ALDH, a stemness marker that positively correlated with FGFR1 and negatively with VDR expression in breast cancer transcriptomic data. In conclusion, the drugs impaired self-aggregation capacity, reduced stemness features, induced cell-differentiation and when combined, synergistically inhibited cell proliferation. Overall, our results suggest that calcitriol, at low pharmacological doses, may be a suitable candidate to synergize AZD4547 effects in luminal B breast tumors, allowing to reduce dose and adverse effects.
成纤维细胞生长因子受体 (FGFR) 在癌症中的过度扩增/激活会导致细胞增殖增加。FGFR 选择性抑制剂 AZD4547 可抑制乳腺癌细胞生长。尽管腔 B 型乳腺癌可能对化疗和内分泌治疗有反应，但这种亚型与预后不良、反应不足和/或获得性耐药有关。钙三醇是维生素 D 最活跃的代谢物，具有抗肿瘤作用，并增强化疗药物的活性。在这项研究中，我们试图通过将其与钙三醇联合使用来降低抑制腔 B 型乳腺癌细胞系 BT-474 增殖所需的 AZD4547 浓度。通过 Sulforhodamine B 测定分析抗增殖抑制浓度、组合指数和剂量减少指数。使用 Western blot 和 qPCR 研究 FGFR 分子靶标。通过肿瘤球体形成评估化合物抑制 BT-474 细胞致瘤能力。结果：BT-474 细胞的生长受到钙三醇和 AZD4547 的剂量依赖性抑制（IC 分别为 2.9 nM 和 3.08 μM）。钙三醇在 1 nM 时协同增强 AZD4547 的抗增殖作用，使 AZD4547 的剂量减少 2 倍。从机制上讲，AZD4547 下调 p-FGFR1、p-Akt 和肿瘤球体形成。钙三醇还减少了肿瘤球体，同时诱导了细胞分化。两种化合物均抑制 MYC 和 CCND1 的表达，以及 ALDH，这是一种干细胞标志物，与乳腺癌转录组数据中 FGFR1 呈正相关，与 VDR 表达呈负相关。总之，这些药物损害了自我聚集能力，降低了干细胞特征，诱导了细胞分化，并且在联合使用时协同抑制了细胞增殖。总的来说，我们的结果表明，在低药理剂量下，钙三醇可能是协同 AZD4547 作用于腔 B 型乳腺癌的合适候选药物，可减少剂量和不良反应。
