Translational Oncology Research Unit, Department of Diagnostic Research and Technological Innovation, IRCCS - Regina Elena National Cancer Institute, Via Elio Chianesi, Rome, 53 - 00144, Italy.
Department of Science, University Roma Tre, Rome, Italy.
J Exp Clin Cancer Res. 2024 Aug 20;43(1):234. doi: 10.1186/s13046-024-03150-4.
Colorectal cancer (CRC) is the third most common type of cancer and the second leading cause of cancer-related deaths worldwide, with a survival rate near to 10% when diagnosed at an advanced stage. Hence, the identification of new molecular targets to design more selective and efficient therapies is urgently required. The Mitogen activated protein kinase kinase 3 (MKK3) is a dual-specificity threonine/tyrosine protein kinase that, activated in response to cellular stress and inflammatory stimuli, regulates a plethora of biological processes. Previous studies revealed novel MKK3 roles in supporting tumor malignancy, as its depletion induces autophagy and cell death in cancer lines of different tumor types, including CRC. Therefore, MKK3 may represent an interesting new therapeutic target in advanced CRC, however selective MKK3 inhibitors are currently not available.
The study involved transcriptomic based drug repurposing approach and confirmatory assays with CRC lines, primary colonocytes and a subset of CRC patient-derived organoids (PDO). Investigations in vitro and in vivo were addressed.
The repurposing approach identified the multitargeted kinase inhibitor AT9283 as a putative compound with MKK3 depletion-mimicking activities. Indeed, AT9283 drops phospho- and total-MKK3 protein levels in tested CRC models. Likely the MKK3 silencing, AT9283 treatment: i) inhibited cell proliferation promoting autophagy and cell death in tested CRC lines and PDOs; ii) resulted well-tolerated by CCD-18Co colonocytes; iii) reduced cancer cell motility inhibiting CRC cell migration and invasion; iv) inhibited COLO205 xenograft tumor growth. Mechanistically, AT9283 abrogated MKK3 protein levels mainly through the inhibition of aurora kinase A (AURKA), impacting on MKK3/AURKA protein-protein interaction and protein stability therefore uncovering the relevance of MKK3/AURKA crosstalk in sustaining CRC malignancy in vitro and in vivo.
Overall, we demonstrated that the anti-tumoral effects triggered by AT9283 treatment recapitulated the MKK3 depletion effects in all tested CRC models in vitro and in vivo, suggesting that AT9283 is a repurposed drug. According to its good tolerance when tested with primary colonocytes (CCD-18CO), AT9283 is a promising drug for the development of novel therapeutic strategies to target MKK3 oncogenic functions in late-stage and metastatic CRC patients.
结直肠癌（CRC）是全球第三大常见癌症类型，也是癌症相关死亡的第二大主要原因，在晚期诊断时，其生存率接近 10%。因此，迫切需要寻找新的分子靶标来设计更具选择性和更有效的治疗方法。丝裂原活化蛋白激酶激酶 3（MKK3）是一种双特异性苏氨酸/酪氨酸蛋白激酶，在细胞应激和炎症刺激下被激活，调节着大量的生物学过程。先前的研究揭示了 MKK3 在支持肿瘤恶性的新作用，因为其耗竭会诱导不同肿瘤类型的癌症系发生自噬和细胞死亡，包括 CRC。因此，MKK3 可能是晚期 CRC 中一个有趣的新治疗靶点，然而，目前还没有选择性的 MKK3 抑制剂。
该研究采用基于转录组的药物再利用方法，并结合 CRC 系、原代结肠细胞和一组 CRC 患者来源的类器官（PDO）进行了确证性检测。在体外和体内进行了研究。
该再利用方法鉴定出多靶点激酶抑制剂 AT9283 是一种具有类似 MKK3 耗竭活性的潜在化合物。事实上，AT9283 降低了测试的 CRC 模型中的磷酸化和总 MKK3 蛋白水平。可能是由于 MKK3 沉默，AT9283 治疗：i）在测试的 CRC 系和 PDO 中促进自噬并诱导细胞死亡，从而抑制细胞增殖；ii）在 CCD-18Co 结肠细胞中耐受性良好；iii）降低癌细胞迁移和侵袭，抑制 CRC 细胞迁移和侵袭；iv）抑制 COLO205 异种移植肿瘤生长。在机制上，AT9283 主要通过抑制极光激酶 A（AURKA）来阻断 MKK3 蛋白水平，影响 MKK3/AURKA 蛋白-蛋白相互作用和蛋白质稳定性，因此揭示了 MKK3/AURKA 串扰在维持 CRC 恶性肿瘤的体外和体内相关性。
总之，我们证明了 AT9283 治疗在所有测试的 CRC 模型中诱导的抗肿瘤作用与 MKK3 耗竭作用相似，这表明 AT9283 是一种重新利用的药物。根据其在原代结肠细胞（CCD-18CO）中的良好耐受性，AT9283 是一种有前途的药物，可用于开发针对晚期和转移性 CRC 患者 MKK3 致癌功能的新型治疗策略。
