New Cu(II) coordination polymer inhibits cervical cancer development by regulating BRCA1 protein via miR-9-5p

Stanniocalcin-1 Promotes PARP1-Dependent Cell Death via JNK Activation in Colitis

Stanniocalcin-1 (STC1) is upregulated by inflammation and modulates oxidative stress-induced cell death. Herein, the function of STC1 in colitis and stress-induced parthanatos, a newly identified type of programmed necrotic cell death dependent on the activation of poly-ADP ribose polymerase-1 (PARP1) is investigated. Results show that STC1 expression is markedly increased in the inflamed colonic mucosa of Crohn's disease (CD) patients and chemically-induced mice colitis models. Evaluation of parthanatos severity and pro-inflammatory cytokine expression shows that intestinal-specific Stc1 knockout (Stc1INT-KO ) mice are resistant to dextran sulfate sodium (DSS)-induced colitis and exhibit lower disease severity. STC1-overexpressing cells show an increased degree of parthanatos and proinflammatory cytokine expression, whereas STC1-knockout cells show a decreased degree of parthanatos. Co-immunoprecipitation, mass spectrometry, and proteomic analyses indicate that STC1 interacts with PARP1, which activates the JNK pathway via PARP1-JNK interactions. Moreover, inhibition of PARP1 and JNK alleviates parthanatos and inflammatory injuries triggered by STC1 overexpression. Finally, following restoration of Stc1 and Parp1 expression by adeno-associated viruses, and overexpression of Stc1 and Parp1 aggravated DSS-induced colitis in Stc1INT-KO mice. In conclusion, STC1 mediates oxidative stress-associated parthanatos and aggravates inflammation via the STC1-PARP1-JNK interactions and subsequent JNK pathway activation in CD pathogenesis.

Curcumin enhances the anti-cancer efficacy of paclitaxel in ovarian cancer by regulating the miR-9-5p/BRCA1 axis

Background: Patients with late-stage ovarian cancer still have a very poor prognosis due to chemotherapy resistance. Curcumin has been shown to synergistically enhance the therapeutic effects of multiple chemotherapeutic agents, but the potential involvement of curcumin in ovarian cancer is largely unknown. This study aimed to investigate whether curcumin has synergistic anti-cancer effects with paclitaxel in ovarian cancer and its underlying mechanism. Methods: Ovarian cancer cell lines (SKOV3 and A2780) were treated with curcumin, alone or combined with paclitaxel. Cell viability, colony formation, EdU incorporation assays, and flow cytometry were used to assess cell proliferation, apoptosis, and cell cycle progression. The cytotoxic synergistic effect of curcumin and paclitaxel was detected by Calcusyn software. RNA immunoprecipitation assay was used to verify the interaction between miR-9-5p and BRCA1. qRT-PCR and Western blot were performed to detect gene and protein expression. Results: We found that curcumin and paclitaxel synergistically inhibited proliferation and promoted apoptosis in ovarian cancer cells. Furthermore, curcumin and paclitaxel combination resulted in decreased miR-9-5p expression and increased BRCA1 expression. Functionally, miR-9-5p overexpression counteracted the synergistic effect of curcumin and paclitaxel on cell proliferation and apoptosis by targeting BRCA1. Meanwhile, in vivo experiments revealed that curcumin and paclitaxel combination dramatically suppressed the growth of transplanted tumors, while miR-9-5p mimics eliminated the growth inhibition of xenografts induced by the combined treatment. Conclusion: Curcumin enhanced the anti-cancer efficacy of paclitaxel in ovarian cancer by regulating the miR-9-5p/BRCA1 axis. These findings provide strong evidence for clinical investigation of curcumin and paclitaxel combination as a novel strategy for ovarian cancer patients, and identify miR-9-5p and BRCA1 as key targets for regulating sensitivity to this therapy.

HDAC8 Promotes Liver Metastasis of Colorectal Cancer via Inhibition of IRF1 and Upregulation of SUCNR1

Histone deacetylases (HDACs) are well-characterized for their involvement in tumor progression. Herein, the current study set out to unravel the association of HDAC8 with colorectal cancer (CRC). Bioinformatics analyses were carried out to retrieve the expression patterns of HDAC8 in CRC and the underlying mechanism. Following expression determination, the specific roles of HDAC8, IRF1, and SUCNR1 in CRC cell functions were analyzed following different interventions. Additionally, tumor formation and liver metastasis in nude mice were operated to verify the fore experiment. Bioinformatics analyses predicted the involvement of the HDAC8/IRF1/SUCNR1 axis in CRC. In vitro cell experiments showed that HDAC8 induced the CRC cell growth by reducing IRF1 expression. Meanwhile, IRF1 limited SUCNR1 expression by binding to its promoter. SUCNR1 triggered the growth and metastasis of CRC by inhibiting cell autophagy. HDAC8 blocked IRF1-mediated SUCNR1 inhibition and thereby inhibited autophagy, accelerating CRC cell growth. Lastly, HDAC8 facilitated the development of CRC and liver metastasis by regulating the IRF1/SUCNR1 axis in vivo. Taken together, our findings highlighted the critical role for the HDAC8/IRF1/SUCNR1 axis in the regulation of autophagy and the resultant liver metastasis in CRC.