Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran.
Pharm Res. 2020 Sep 17;37(10):196. doi: 10.1007/s11095-020-02892-y.
Hypoxia-inducible factor (HIF) is one of the critical components of the tumor microenvironment that is involved in tumor development. HIF-1α functionally and physically interacts with CDK1, 2, and 5 and stimulates the cell cycle progression and Cyclin-Dependent Kinase (CDK) expression. Therefore, hypoxic tumor microenvironment and CDK overexpression lead to increased cell cycle progression and tumor expansion. Therefore, we decided to suppress cancer cell expansion by blocking HIF-1α and CDK molecules.
In the present study, we used the carboxylated graphene oxide (CGO) conjugated with trimethyl chitosan (TMC) and hyaluronate (HA) nanoparticles (NPs) loaded with HIF-1α-siRNA and Dinaciclib, the CDK inhibitor, for silencing HIF-1α and blockade of CDKs in CD44-expressing cancer cells and evaluated the impact of combination therapy on proliferation, metastasis, apoptosis, and tumor growth.
The results indicated that the manufactured NPs had conceivable physicochemical properties, high cellular uptake, and low toxicity. Moreover, combination therapy of cancer cells using CGO-TMC-HA NPs loaded with HIF-1α siRNA and Dinaciclib (SCH 727965) significantly suppressed the CDKs/HIF-1α and consequently, decreased the proliferation, migration, angiogenesis, and colony formation in tumor cells.
These results indicate the ability of CGO-TMC-HA NPs for dual drug/gene delivery in cancer treatment. Furthermore, the simultaneous inhibition of CDKs/HIF-1α can be considered as a novel anti-cancer treatment strategy; however, further research is needed to confirm this treatment in vivo. Graphical Abstract The suppression of HIF-1α and CDKs inhibits cancer growth. HIF-1α is overexpressed by the cells present in the tumor microenvironment. The hypoxic environment elevates mitochondrial ROS production and increases p38 MAP kinase, JAK/STAT, ERK, JNK, and Akt/PI3K signaling, resulting in cyclin accumulation and aberrant cell cycle progression. Furthermore, the overexpression of HIF-1α/CDK results in increased expression of genes such as BCL2, Bcl-xl, Ki-67, TGFβ, VEGF, FGF, MMP2, MMP9, and, HIF-1α and consequently raise the survival, proliferation, angiogenesis, metastasis, and invasion of tumor cells. In conclusion, HIF-1α-siRNA/Dinaciclib-loaded CGO-TMC-HA NPs can inhibit the tumor expansion by blockage of CDKs and HIF-1α (JAK: Janus kinase, STAT: Signal transducer and activator of transcription, MAPK: mitogen-activated protein kinase, ERK: extracellular signal-regulated kinase, JNK: c-Jun N-terminal kinase, PI3K: phosphatidylinositol 3-kinase).
缺氧诱导因子（HIF）是肿瘤微环境的关键组成部分之一，参与肿瘤的发展。HIF-1α 与 CDK1、2 和 5 功能上和物理上相互作用，刺激细胞周期进程和细胞周期蛋白依赖性激酶（CDK）的表达。因此，低氧肿瘤微环境和 CDK 过表达导致细胞周期进程加快和肿瘤扩张。因此，我们决定通过阻断 HIF-1α 和 CDK 分子来抑制癌细胞的扩增。
在本研究中，我们使用了羧基化氧化石墨烯（CGO）与三甲基壳聚糖（TMC）和透明质酸（HA）纳米粒子（NPs）结合，负载 HIF-1α-siRNA 和 Dinaciclib，即 CDK 抑制剂，用于沉默 CD44 表达的癌细胞中的 HIF-1α 和阻断 CDKs，并评估联合治疗对增殖、转移、凋亡和肿瘤生长的影响。
结果表明，所制备的 NPs 具有理想的物理化学性质、高细胞摄取率和低毒性。此外，使用负载 HIF-1α siRNA 和 Dinaciclib（SCH 727965）的 CGO-TMC-HA NPs 联合治疗癌细胞，显著抑制了 CDKs/HIF-1α，从而降低了肿瘤细胞的增殖、迁移、血管生成和集落形成。
这些结果表明 CGO-TMC-HA NPs 具有用于癌症治疗的双重药物/基因传递能力。此外，同时抑制 CDKs/HIF-1α 可以被认为是一种新的抗癌治疗策略；然而，需要进一步的研究来确认这种治疗方法在体内的效果。
抑制 HIF-1α 和 CDK 抑制肿瘤生长。HIF-1α 由肿瘤微环境中存在的细胞过表达。低氧环境会增加线粒体 ROS 的产生，并增加 p38 MAP 激酶、JAK/STAT、ERK、JNK 和 Akt/PI3K 信号通路，导致细胞周期蛋白积累和异常细胞周期进程。此外，HIF-1α/CDK 的过表达导致 BCL2、Bcl-xl、Ki-67、TGFβ、VEGF、FGF、MMP2、MMP9 和 HIF-1α 等基因的表达增加，从而提高肿瘤细胞的存活、增殖、血管生成、转移和侵袭能力。总之，负载 HIF-1α-siRNA 和 Dinaciclib 的 CGO-TMC-HA NPs 可以通过阻断 CDKs 和 HIF-1α 抑制肿瘤的扩张（JAK：Janus 激酶，STAT：信号转导和转录激活因子，MAPK：丝裂原激活的蛋白激酶，ERK：细胞外信号调节激酶，JNK：c-Jun N-末端激酶，PI3K：磷脂酰肌醇 3-激酶）。
