Background: Pancreatic cancer remains one of the most rapidly progressive and deadly malignancies worldwide. Current treatment regimens only result in small improvements in overall survival for patients with this cancer type. CPI-613 (Devimistat), a novel lipoate analog inhibiting mitochondrial metabolism, shows the new hope for pancreatic cancer treatment as an efficient and well-tolerated therapeutic option treated alone or in combination with chemotherapy. Methods: Pancreatic cancer cells growing in planar 2D cultures and 3D scaffold were used as research platforms. Cell viability was measured by MTT and alamarBlue, and apoptosis was assessed by JC-1 staining and flow cytometry with Annexin V-FITC/PI staining. The mechanism behind CPI-613 action was analyzed by western blot, transmission electron microscopy, and lipolysis assay kits, in the presence or absence of additional signaling pathway inhibitors or gene modifications. Results: CPI-613 exhibits anticancer activity in pancreatic cancer cells by triggering ROS-associated apoptosis, which is accompanied by increased autophagy and repressed lipid metabolism through activating the AMPK signaling. Intriguingly, ACC, the key enzyme modulating lipid metabolism, is identified as a vital target of CPI-613, which is inactivated in an AMPK-dependent manner and influences apoptotic process upon CPI-613. Blockade or enhancement of autophagic process does not increase or blunt apoptosis to CPI-613, but inhibition of the AMPK-ACC signaling significantly attenuates apoptosis induced by CPI-613, suggesting CPI-613-mediated lipid metabolism reduction contributes to its cytotoxicity in pancreatic cancer cells. Conclusions: These findings explore the critical role of lipid metabolism in apoptosis, providing new insights into the AMPK-ACC signaling axis in crosstalk between lipid metabolism and apoptosis in CPI-613 treatment.

Mitochondria, as the powerhouse of most cells, are not only responsible for the generation of adenosine triphosphate (ATP) but also play a decisive role in the regulation of apoptotic cell death, especially of cancer cells. Safe potential delivery systems which can achieve organelle-targeted therapy are urgently required. In this study, for effective pancreatic cancer therapy, a novel mitochondria-targeted and ROS-triggered drug delivery nanoplatform was developed from the TPP-TK-CPI-613 (TTCI) prodrug, in which the ROS-cleave thioketal functions as a linker connecting mitochondrial targeting ligand TPP and anti-mitochondrial metabolism agent CPI-613. DSPE-PEG2000 was added as an assistant component to increase accumulation in the tumor via the EPR effect. This new nanoplatform showed effective mitochondrial targeting, ROS-cleaving capability, and robust therapeutic performances. With active mitochondrial targeting, the formulated nanoparticles (TTCI NPs) demonstrate much higher accumulation in mitochondria, facilitating the targeted delivery of CPI-613 to its acting site. The results of in vitro antitumor activity and cell apoptosis revealed that the IC₅₀ values of TTCI NPs in three types of pancreatic cancer cells were around 20~30 µM, which was far lower than those of CPI-613 (200 µM); 50 µM TTCI NPs showed an increase in apoptosis of up to 97.3% in BxPC3 cells. Therefore, this mitochondria-targeted prodrug nanoparticle platform provides a potential strategy for developing safe, targeting and efficient drug delivery systems for pancreatic cancer therapy.

Palbociclib is the world's first CDK4/6 kinase inhibitor to be marketed. However, it is not effective in the treatment of triple negative breast cancer (TNBC) due to the loss of retinoblastoma protein expression. Thus, combinatorial chemotherapy is indispensable for TNBC treatment. Herein, a carrier-free nanomedicine self-assembled from palbociclib dimers and Ce6 for enhanced combined chemo-photodynamic therapy of breast cancer is reported. The dimeric prodrug (Palb-TK-Palb) was synthesized by conjugating two palbociclib molecules to the connecting skeleton containing a ROS-responsive cleavable thioketal bond. The Palb-TK-Palb/Ce6 NP co-delivery nanoplatform was prepared through the self-assembly of Palb-TK-Palb, Ce6 and DSPE-PEG2000. This novel carrier-free formulation as an efficient therapeutic agent showed efficient therapeutic agent loading capacity, high cellular uptake and huge therapeutic performance against breast cancer cells. The results of in vitro antitumor activity and cell apoptosis demonstrated that Palb-TK-Palb/Ce6 NPs presented a better inhibitory effect on the growth of cancer cells due to the palbociclib and Ce6 co-delivery nanomedicine-mediated synergistic chemo-photodynamic therapy. The IC₅₀ values of Palb-TK-Palb/Ce6 NPs in MDA-MB-231 cells were around 1–2 μM and 2 μM and the Palb-TK-Palb/Ce6 NPs showed an increase in apoptosis up to 91.9%. In general, the carrier-free nanomedicine self-assembled from palbociclib dimers and Ce6 provides options for combinatorial chemo-photodynamic therapy.

N⁶-methyladenosine (m⁶A) is the most common RNA modification in eukaryotic RNAs. Although the important roles of m⁶A in RNA fate have been revealed, the potential contribution of m⁶A to RNA function in various diseases, including hepatocellular carcinoma (HCC), is still unclear. In this study, we identified a novel m⁶A-modified RNA AC026356.1. We found that AC026356.1 was increased in HCC tissues and cell lines. High expression of AC026356.1 was correlated with poor survival of HCC patients. m⁶A modification level of AC026356.1 was also increased in HCC and more significantly correlated with poor survival of HCC patients. Functional assays showed that m⁶A-modified AC026356.1 promoted HCC cellular proliferation, migration, and liver metastasis. Gene set enrichment analysis showed that AC026356.1 activated IL11/STAT3 signaling. Mechanistic investigation showed that m⁶A-modified AC026356.1 bound to IGF2BP1. The interaction between m⁶A-modified AC026356.1 and IGF2BP1 promoted the binding of IL11 mRNA to IGF2BP1, leading to increased IL11 mRNA stability and IL11 secretion. Functional rescue assays showed that depletion of IL11 reversed the oncogenic roles of AC026356.1. These findings revealed the potential influences of m⁶A modification on RNA biological functions and suggested that targeting m⁶A modification may be a novel strategy for HCC treatment.

In this study, we developed coordinative amphiphiles for use as novel non-viral DNA vectors. As a modification of a conventional cationic lipid structure, we replaced the cationic head with a zinc(II)-1,4,7,10-tetraazacyclododecane (Zn-cyclen) complex as a phosphate-directing group, and used biocompatible skeletons (α-tocopherol or cholesterol) as hydrophobic tails. The structure-activity relationship (SAR) was systematically investigated to study the effect of Zn-coordination on the gene transfection between cyclen-based traditional head-tail lipids and Zn(II)-cyclen coordinative amphiphiles. The results reveal that both Zn-free lipids and Zn-containing amphiphiles could condense DNA into nano-sized particles with appropriate size and zeta-potentials. Agarose gel retardation assay and MTS-based cell viability assays demonstrated that the Zn(II)-cyclen complex exhibited slightly lower DNA binding ability and much lower cytotoxicity compared to liposome analogues, respectively. Most importantly, in vitro transfection studies showed that the coordination of zinc(II) to cyclen may dramatically increase the transfection efficiency of the conventional cationic lipid, and α-tocopherol-containing coordinative amphiphile Zn-Cyc-Toc gives the best transfection efficiency, which was enhanced 24.4 times after coordination and was 6.1 times higher than commercial transfection reagent lipofectamine 2000. Mechanism studies confirmed that the DNA complex formed from Zn-Cyc-Toc might induce higher cellular uptake and better endosomal escape ability than the lipoplexes formed from Zn-free lipid Cyc-Toc. This study not only demonstrates that these coordinative amphiphiles might be promising non-viral gene vectors, but also presents a novel strategy to enhance the gene transfection efficiency and biocompatibility of cyclen-based cationic lipids.