Effects of the Novel PFKFB3 Inhibitor KAN0438757 on Colorectal Cancer Cells and Its Systemic Toxicity Evaluation In Vivo

Abstract

Background: Despite substantial progress made in the last decades in colorectal cancer (CRC) research, new treatment approaches are still needed to improve patients’ long-term survival. To date, the promising strategy to target tumor angiogenesis metabolically together with a sensitization of CRC to chemo- and/or radiotherapy by PFKFB3 (6-phosphofructo-2-kinase/fructose-2,6-biphosphatase-3) inhibition has never been tested. Therefore, initial evaluation and validation of newly developed compounds such as KAN0438757 and their effects on CRC cells are crucial steps preceding to in vivo preclinical studies, which in turn may consolidate new therapeutic targets. Materials and Methods: The efficiency of KAN0438757 to block PFKFB3 expression and translation in human CRC cells was evaluated by immunoblotting and real-time PCR. Functional in vitro assays assessed the effects of KAN0438757 on cell viability, proliferation, survival, adhesion, migration and invasion. Additionally, we evaluated the effects of KAN0438757 on matched patient-derived normal and tumor organoids and its systemic toxicity in vivo in C57BL6/N mice. Results: High PFKFB3 expression is correlated with a worse survival in CRC patients. KAN0438757 reduces PFKFB3 protein expression without affecting its transcriptional regulation. Additionally, a concentration-dependent anti-proliferative effect was observed. The migration and invasion capacity of cancer cells were significantly reduced, independent of the anti-proliferative effect. When treating colonic patient-derived organoids with KAN0438757 an impressive effect on tumor organoids growth was apparent, surprisingly sparing normal colonic organoids. No high-grade toxicity was observed in vivo. Conclusion: The PFKFB3 inhibitor KAN0438757 significantly reduced CRC cell migration, invasion and survival. Moreover, on patient-derived cancer organoids KAN0438757 showed significant effects on growth, without being overly toxic in normal colon organoids and healthy mice. Our findings strongly encourage further translational studies to evaluate KAN0438757 in CRC therapy.

PFKFB3 Inhibition Sensitizes DNA Crosslinking Chemotherapies by Suppressing Fanconi Anemia Repair

“…To determine the contribution of PFKFB3 activity in the response to platinum, we performed drug combination screenings in a dose-response matrix across a panel of cancer cell lines using the PFKFB3 inhibitor KAN0438757 [ 25 , 38 ], hereafter referred to as PFKFB3i, given its inhibition of PFKFB3 enzymatic activity, proven target engagement, and isoenzyme selectivity [ 25 ]. Strong synergy scores between PFKFB3i and platinum-based drugs were observed in all cancer cell lines tested ( Figure 1 A–C).…”

Canonical and Non-Canonical Roles of PFKFB3 in Brain Tumors

“…However, targeted PFKFB3 inhibition may provide a therapeutic option for CNS tumor patients. PFKFB3 inhibitor therapy has been observed to restore chemosensitivity and radiosensitivity in treatment-resistant tumors [ 26 , 51 , 113 , 162 , 163 , 164 , 165 ]. Combined anti-PFKFB3 and anti-VEGF therapy has been noted to improve the survival of glioblastoma preclinical models and abrogate resistance to anti-angiogenic therapy [ 97 ].…”

“…KAN0438757 blocked HR repair activity and prevented dNTPs from being incorporated during double-strand break DNA repair, evidenced by persistently high levels of γH2AX and delayed recovery from IR-induced cell cycle arrest [ 26 ]. In- vivo administration of KAN0438757 did not show any systemic toxicity and was well tolerated even at the highest dose of 50 mg/kg in immune competent mice [ 164 ].…”

“…Concomitant PFKFB3 inhibition has additionally shown great potential in restoring chemosensitivity and radiosensitivity in treatment resistant tumors [ 26 , 51 , 113 , 162 , 163 , 164 , 165 ]. Platinum-based chemotherapy resistance, which commonly occurs particularly through RAD51-induced HR, was reversed with the addition of PFK158 to the carboplatin/cisplatin chemotherapeutic regimen [ 163 ].…”

Revisited Metabolic Control and Reprogramming Cancers by Means of the Warburg Effect in Tumor Cells

“…In clinical cancers including lung cancers, osteosarcoma, and breast cancer, PFKFB3 expression indicates poor survival rates [ 37 ]. Tumorigenic potentials of PFKFB3-expressing colon cancer cells are targeted by its inhibitory agent to regress metastasis [ 38 ]. PFKFB3 also induces non-stem cell differentiation to cancer stem cells, depending on the glycolysis [ 39 ] and supporting the direct role in rapid cell proliferation and metastasis of cancer cells.…”