Pitavastatin induces autophagy-dependent ferroptosis in MDA-MB-231 cells via the mevalonate pathway.

Triple-negative breast cancer (TNBC) is more prone to recurrence and metastasis relative to other subtypes of breast cancer, leading to an extremely poor prognosis. The increasing potential chemoresistance of TNBC patients is mainly due to that tumor cells escape from apoptosis. In recent years, statins have demonstrated extensive anti-tumor effects. It is worth noting that statins have more effective anti-tumor effects on TNBC cells and drug-resistant breast cancer cells. Therefore, this study examines the superior cytotoxic effects of statins on TNBC cell lines and further explores their potential therapeutic mechanisms. We detected different cell phenotypes and found that statins significantly reduced the cell viability of TNBC cells. Specifically, pitavastatin showed an obvious induction in cell death, cell cycle arrest and oxidative stress in TNBC MDA-MB-231 cells. The reversal effect of iron chelator desferrioxamine (DFO) on the morphological and molecular biological changes induced by pitavastatin has revealed a new mode of cell death induced by pitavastatin: ferroptosis. This ferroptotic effect was strengthened by the decreased expression of glutathione peroxidase 4 (GPx4) as well as newly discovered ferroptosis suppressor protein 1 (FSP1). The data showed that ferroptotic death of MDA-MB-231 cells is autophagy-dependent and mediated by the mevalonate pathway. Finally, we found that therapeutic oral doses of statins can inhibit the growth of transplanted tumors, which establishes statins as a potential treatment for TNBC patients. In conclusion, we found pitavastatin could induce autophagy-dependent ferroptosis in TNBC cells via the mevalonate pathway which may become a potential adjuvant treatment option for TNBC patients.

Prenatal Diagnosis and Genetic Counseling of a Maternally Inherited Chromosome 15q11.2q13.1 Duplication in a Chinese Family.

Background: Maternally inherited chromosomal duplications in the region of 15q11.2q13.1 have been associated with neurodevelopmental disorders and other clinical manifestations. Prenatal diagnosis of such duplications is crucial for providing accurate genetic counseling and guiding clinical management decisions. Objective: This study aims to present the prenatal diagnosis and genetic counseling of a maternally inherited 15q11.2q13.1 duplication. Case Presentation: A 38-year-old gravida 1, para 0 woman underwent amniocentesis at 16 weeks of gestation due to advanced maternal age. Karyotype analysis was performed on cultured amniocytes, and chromosomal microarray analysis (CMA) was conducted on uncultured amniocytes. Results: The karyotype analysis of the cultured amniocytes revealed a normal karyotype of 46, XX. CMA identified a 4.21 Mb maternally inherited chromosomal duplication in the region of 15q11.2q13.1 (arr[GRCh37]15q11.2q13.1(23,894,550_28,107,154)x3). Conclusions: Copy number variants (CNVs) and unbalanced chromosomal abnormalities (UBCA) identified in prenatal cases require careful consideration and accurate interpretation to determine their potential harm or harmlessness compared to the norm. The combination of prenatal ultrasound, karyotype analysis, CMA, and genetic counseling proves helpful in the prenatal diagnosis of CNVs and UBCA.

Hyperthermia promotes exosome secretion by regulating Rab7b while increasing drug sensitivity in adriamycin-resistant breast cancer.

PURPOSE: To investigate the mechanism through which hyperthermia promotes exosome secretion and drug sensitivity in adriamycin-resistant breast cancer. MATERIALS AND METHODS: We first evaluated the effect of hyperthermia on adriamycin-resistant breast cancer viability and used transmission electron microscopy, nanoparticle tracking analysis, and a bicinchoninic acid kit to validate the effect of hyperthermia on exosome secretion. The effective targeting molecules and pathways changed by hyperthermia were explored by RNA microarray and verified in vitro. The adriamycin-resistant MCF-7/ADR cells co-incubated with the exosomes produced by MCF-7/ADR cells after hyperthermia were assessed. The uptake of exosomes by MCF-7/ADR cells after hyperthermia treatment was evaluated by confocal microscopy. Finally, the mechanism through which hyperthermia promotes exosome secretion by hyperthermia was determined. RESULTS: Hyperthermia significantly suppressed the growth of adriamycin-resistant breast cancer cells and increased drug sensitivity by upregulating FOS and CREB5, genes related to longer overall survival in breast cancer patients. Moreover, hyperthermia promoted exosome secretion through Rab7b, a small GTPase that controls endosome transport. The upregulated FOS and CREB5 antioncogenes can be transferred to MCF-7/ADR cells by hyperthermia-treated MCF-7/ADR cell-secreted exosomes. CONCLUSIONS: Our results demonstrated a novel function of hyperthermia in promoting exosome secretion in adriamycin-resistant breast cancer cells and revealed the effects of hyperthermia on tumor cell biology. These hyperthermia-triggered exosomes can carry antitumor genes to the residual tumor and tumor microenvironment, which may be more beneficial to the effects of hyperthermia. These results represent an exploration of the relationship between therapeutic strategies and exosome biology.

Silencing of MEF2D by siRNA Loaded Selenium Nanoparticles for Ovarian Cancer Therapy.

BACKGROUND: Delivery of therapeutic small interfering RNA (siRNA) via functionalized nanoparticles holds great promise for cancer therapy. However, developing a safe and efficient delivery carrier of siRNA is a challenging issue. METHODS: RGDfC peptide was used to modify the surface of selenium nanoparticles (SeNPs) to synthesize a biocompatible siRNA delivery vehicle (R-SeNPs), and MEF2D-siRNA was loaded onto R-SeNPs to prepare a functionalized selenium nanoparticle R-Se@MEF2D-siRNA. The chemical properties of R-SeNPs were characterized, and the anticancer efficacy as well as related mechanisms of R-Se@MEF2D-siRNA were further explored. RESULTS: R-Se@MEF2D-siRNA was significantly taken up by SKOV3 cells and could enter SKOV3 cells mainly in the clathrin-associated endocytosis way. The result of in vitro siRNA release demonstrated that R-Se@MEF2D-siRNA could release MEF2D-siRNA quicker in a microenvironment simulating a lysosomal environment in tumor cells compared to a normal physiological environment. The results of qRT-PCR assay proved that R-Se@MEF2D-siRNA could effectively silence the expression of the MEF2D gene in SKOV3 cells. R-Se@MEF2D-siRNA remarkably suppressed the proliferation of SKOV3 cells and further triggered its apoptosis. In addition, R-Se@MEF2D-siRNA had the capability to disrupt mitochondrial membrane potential (MMP) in SKOV3 cells and resulted in the overproduction of reactive oxygen species (ROS), indicating that mitochondrial dysfunction and ROS generation played an important role in the apoptosis of SKOV3 cells induced by R-Se@MEF2D-siRNA. In vivo, R-Se@MEF2D-siRNA also exhibited excellent antitumor activity mainly through decreasing tumor cells proliferation and triggering their apoptosis in tumor-bearing nude mice. CONCLUSION: R-Se@MEF2D-siRNA provides an alternative strategy for ovarian cancer treatment in the clinic.

Ozone therapy induced sinus arrest in a hypertensive patient with chronic kidney disease: A case report.

RATIONALE: Ozone autohemotherapy as an alternative treatment method has been applied to the treatment of several diseases. Here, we report a patient used ozone autohemotherapy to treat her hypertension and diabetes. Nevertheless, the patient occurred sudden dizziness and black haze due to hyperkalemia. PATIENT CONCERNS: A 54-year-old woman who was admitted to our emergency department complaining of sudden dizziness and black haze for 5 hours. DIAGNOSES: The blood potassium test showed hyperkalemia. Upon further inquiry of her medical history, the patient received ozone autohemotherapy to treat hypertension and diabetes for 9 days prior to admission. INTERVENTIONS: The ozone therapy had been asked to stop. Insulin, sodium bicarbonate, and sodium polystyrene sulfonate were administered to the patient. OUTCOMES: After treatment, blood potassium remained in the normal range. After 3 days of treatment, the 24-hour dynamic electrocardiogram revealed sinus rhythm with an average heart rate of 82 beats/min, occasional ventricular premature beats, occasional ventricular premature beats, and no ST segment depression. LESSONS: Although ozone therapy is widely used in the treatment of several diseases, adverse reactions should be given attention in clinical practice, especially in patients with chronic kidney disease.