Department of Gynecology and Obstetrics, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany.
Institute of Pathology, Kaufbeuren, Germany.
Arch Gynecol Obstet. 2022 Oct;306(4):1197-1210. doi: 10.1007/s00404-022-06434-2. Epub 2022 Mar 17.
Protein kinase C (PKC) plays a pivotal role in malignant cell proliferation, apoptosis, invasiveness and migration. However, its exploitation as therapeutic target in breast cancer has been merely explored. Here were evaluated the AEB071 (Sotrastaurin™) treatment efficiency of breast cancer cell lines derived from estrogen receptor positive (T-47D), estrogen/HER2 receptor positive (BT474), and triple negative (HCC1806) breast cancer cells under 2D (monolayer) and 3D (multicellular tumor spheroids) culture conditions. Additionally, spheroid cocultures of BC and N1 fibroblasts were analyzed.
We quantitatively assessed the proliferation capacity of breast cancer cells and fibroblasts as a function of AEB071 treatment using flow cytometry. The activities of PKC isoforms, substrates, and key molecules of the PKC signaling known to be involved in the regulation of tumor cell proliferation and cellular survival were additionally evaluated. Moreover, a multigene expression analysis (PanCancer Pathways assay) using the nanoString™ technology was applied.
All breast cancer cell lines subjected to this study were sensitive to AEB071 treatment, whereby cell proliferation in 2D culture was considerably (BT474) or moderately (HCC1806) retarded in G0/G1 or in G2/M phase (T-47D) of the cell cycle. Regardless of the breast cancer subtype the efficiency of AEB071 treatment was significantly lower in the presence of N1 fibroblast cells. Subtype specific driver molecules, namely IL19, c-myb, and NGFR were mostly affected by the AEB071 treatment.
A combined targeting of PKC and a subtype specific driver molecule might complement specified breast cancer treatment.
蛋白激酶 C（PKC）在恶性细胞增殖、凋亡、侵袭和迁移中发挥关键作用。然而，将其作为乳腺癌的治疗靶点的探索还仅仅处于起步阶段。本研究评估了 AEB071（Sotrastaurin™）在雌激素受体阳性（T-47D）、雌激素/HER2 受体阳性（BT474）和三阴性（HCC1806）乳腺癌细胞系中的治疗效果，这些细胞系分别来自乳腺癌细胞，在 2D（单层）和 3D（多细胞肿瘤球体）培养条件下进行培养。此外，还分析了 BC 和 N1 成纤维细胞球体共培养的情况。
我们使用流式细胞术定量评估了乳腺癌细胞和成纤维细胞在 AEB071 治疗下的增殖能力。还评估了 PKC 同工酶、底物以及已知参与调节肿瘤细胞增殖和细胞存活的 PKC 信号关键分子的活性。此外，还应用了基于纳米String™技术的多基因表达分析（PanCancer Pathways assay）。
本研究中所有的乳腺癌细胞系均对 AEB071 治疗敏感，其中 BT474 细胞在 2D 培养中细胞增殖明显（BT474）或中度（HCC1806）受到抑制，细胞周期处于 G0/G1 或 G2/M 期（T-47D）。无论乳腺癌亚型如何，在存在 N1 成纤维细胞的情况下，AEB071 治疗的效率显著降低。亚型特异性的驱动分子，即 IL19、c-myb 和 NGFR，大多数受到 AEB071 治疗的影响。
联合靶向 PKC 和亚型特异性驱动分子可能会补充特定的乳腺癌治疗。
