The crosstalk between classic cell signaling pathways, non-coding RNAs and ferroptosis in drug resistance of tumors

Arsenic induces ferroptosis in HTR-8/SVneo cells and placental damage

Placenta ferroptosis has been proven to be associated with a variety of adverse pregnancy outcomes. Arsenic, a conventional metal noxious substance, has garnered considerable attention due to traversing the placental barrier. How arsenic induces placental ferroptosis and reproductive developmental toxicities remains largely unknown. Herein, we investigated the impact of sodium arsenite (As (III)) on iron homeostasis in the placenta through both in vivo and in vitro experiments by using HTR-8/SVneo cells and ICR pregnant mice. As (III) up-regulated the expression of genes or proteins associated with iron uptake (TFRC, DMT1), iron storage (FTH, FTL), ferritin autophagy (NCOA4), and heme degradation (HO-1), and induced cell iron overload. Additionally, accumulation of the lipid hydroperoxide malondialdehyde within cells was triggered by As (III) through inhibition of the Nrf2/GPX4 signal pathway, which resulted in cellular ferroptosis. Fer-1 effectively alleviated the suppression of GPX4 induced by As (III), reduced the accumulation of intracellular lipid peroxidation product MDA, and mitigated cellular ferroptosis. As (III) affected the iron homeostasis, as evidenced by the abnormal iron accumulation in the placenta. Placental structural abnormalities and hemorrhage may be the reason for As (III) causing placental injury and subsequent poor pregnancy outcomes. This study provides new insights into understanding the mechanisms by which As (III) produces placental damage and possible fetal developmental toxicity.

Therapeutic potential of flavonoids from traditional Chinese medicine in pancreatic cancer treatment

Pancreatic cancer (PC) is a highly aggressive malignancy with rising mortality rates globally. Its diagnosis is often challenging due to its asymptomatic nature in the early stages. Consequently, most patients receive a poor prognosis, with low survival rates within 5 years, as the disease is typically detected at an advanced stage, complicating effective treatment. Flavonoids, especially those derived from traditional Chinese herbal medicines, have attracted considerable attention for their potent anti-PC properties. This review highlights the therapeutic potential of these bioactive compounds, which modulate key biological pathways, making them promising candidates for PC intervention. Their mechanisms of action include the regulation of autophagy, apoptosis, cell growth, epithelial-mesenchymal transition, and oxidative stress, as well as enhancing chemotherapeutic sensitivity, exerting antiangiogenic effects, and potentially boosting immunomodulatory responses. The demonstrated benefits of these natural compounds in cancer management have spurred extensive academic interest. Beyond their role as anti-cancer agents, flavonoids may provide both preventive and therapeutic advantages for PC, resonating with the core principles of traditional Chinese medicine for disease prevention and holistic treatment.

The crosstalk between oncogenic signaling and ferroptosis in cancer

Ferroptosis, a novel form of cell death regulation, was identified in 2012. It is characterized by unique features that differentiate it from other types of cell death, including necrosis, apoptosis, autophagy, and pyroptosis. Ferroptosis is defined by an abundance of iron ions and lipid peroxidation, resulting in alterations in subcellular structures, an elevation in reactive oxygen species (ROS), a reduction in glutathione (GSH) levels, and an augmentation in Fe (II) cytokines. Ferroptosis, a regulated process, is controlled by an intricate network of signaling pathways, where multiple stimuli can either enhance or hinder the process. This review primarily examines the defensive mechanisms of ferroptosis and its interaction with the tumor microenvironment. The analysis focuses on the pathways that involve AMPK, p53, NF2, mTOR, System Xc-, Wnt, Hippo, Nrf2, and cGAS-STING. The text discusses the possibilities of employing a combination therapy that targets several pathways for the treatment of cancer. It emphasizes the necessity for additional study in this field.

Inhibition of Apoc1 reverses resistance of sorafenib by promoting ferroptosis in esophageal cancers

Drug resistance is an obstacle in therapy of esophageal cancers (ECs), and the role of ferroptosis in progression ECs is still not clearly clarified. In the present study, we investigated the role of Apolipoprotein C1 (Apoc1) in regulating the sorafenib resistance in EC cells. Apoc1 was knock down after infection with Apoc1 shRNA lentivirus and stable cell lines for Apoc1 knockdown were screened. Cell viabilities were tested by MTT assay. ROS, MDA, and GSH tested by specific kits. In vivo experiment in nude mice were performed to test the correlation of Apoc1 and ferroptosis. The expression of Apoc1 and GPX4 was tested by western blotting. The results showed that Apoc1 was highly expressed in EC tissues and associated with poor overall survival rate of EC. Knockdown Apoc1 overcame resistance of sorafenib in EC cells and promoted erastin and sorafenib induced ferroptosis by upregulating the levels of ROS and MDA and downregulating the level of GSH in OE19/Sora and EC109/Sora cells. Rescue experiments proved that Apoc1 regulated sorafenib induced ferroptosis via GPX4. Furthermore, knockdown of Apoc1 inhibited the tumor progression by promoting ferroptosis in nude mice. In conclusion, knockdown Apoc1 overcome resistance of sorafenib in EC cells and in vivo by promoting sorafenib induced ferroptosis via GPX4. Targeting Apoc1 might be an effective way to reverse the drug resistance of sorafenib via inducing ferroptosis in EC progression.

LncRNA-associated competing endogenous RNA network analysis uncovered key lncRNAs involved in temozolomide resistance and tumor recurrence of glioblastoma

Temozolomide (TMZ) is a common alkylating chemotherapeutic agent used to treat brain tumors such as glioblastoma multiforme (GBM) and anaplastic astrocytoma. GBM patients develop resistance to this drug, which has an unclear and complicated molecular mechanism. The competing endogenous RNAs (ceRNAs) play critical roles in tumorigenesis, drug resistance, and tumor recurrence in cancers. This study aims to predict ceRNAs, their possible involvement, and underlying molecular mechanisms in TMZ resistance. Therefore, we analyzed coding and non-coding RNA expression levels in TMZ-resistant GBM samples compared to sensitive GBM samples and performed pathway analysis of mRNAs differentially expressed (DE) in TMZ-resistant samples. We next applied a mathematical model on 950 DE long non-coding RNAs (lncRNAs), 116 microRNAs (miRNAs), and 7977 mRNAs and obtained 10 lncRNA-associated ceRNAs that may be regulating potential target genes involved in cancer-related pathways by sponging 25 miRNAs in TMZ-resistant GBM. Among these, two lncRNAs named ARFRP1 and RUSC2 regulate five target genes (IRS1, FOXG1, GNG2, RUNX2, and CACNA1E) involved in AMPK, AKT, mTOR, and TGF-β signaling pathways that activate or inhibit autophagy causing TMZ resistance. The novel lncRNA-associated ceRNA network predicted in GBM offers a fresh viewpoint on TMZ resistance, which might contribute to treating this malignancy.