Iron is an essential nutrient for mammals as well as for pathogens. Inflammation-driven changes in systemic and cellular iron homeostasis are central for host-mediated antimicrobial strategies. Here, we studied the role of the iron storage protein ferritin H (FTH) for the control of infections with the intracellular pathogen Salmonella enterica serovar Typhimurium by macrophages. Mice lacking FTH in the myeloid lineage ( LysM-Cre ^+/+ Fth ^fl/fl mice) displayed impaired iron storage capacities in the tissue leukocyte compartment, increased levels of labile iron in macrophages, and an accelerated macrophage-mediated iron turnover. While under steady-state conditions, LysM-Cre ^+/+ Fth ^+/+ and LysM-Cre ^+/+ Fth ^fl/fl animals showed comparable susceptibility to Salmonella infection, i.v. iron supplementation drastically shortened survival of LysM-Cre ^+/+ Fth ^fl/fl mice. Mechanistically, these animals displayed increased bacterial burden, which contributed to uncontrolled triggering of NF-κB and inflammasome signaling and development of cytokine storm and death. Importantly, pharmacologic inhibition of the inflammasome and IL-1β pathways reduced cytokine levels and mortality and partly restored infection control in iron-treated ferritin-deficient mice. These findings uncover incompletely characterized roles of ferritin and cellular iron turnover in myeloid cells in controlling bacterial spread and for modulating NF-κB and inflammasome-mediated cytokine activation, which may be of vital importance in iron-overloaded individuals suffering from severe infections and sepsis.

Unfavorable clinical outcomes mean that cancer researchers must attempt to develop novel therapeutic strategies to overcome therapeutic resistance in patients with HNSCC. Recently, ferroptosis was shown to be a promising pathway possessing druggable targets, such as xCT (SLC7A11). Unfortunately, little is known about the molecular mechanisms underlying the susceptibility of HNSCC cells to ferroptosis. The goal of this study was to determine whether HNSCC cells with activated Erk1/2 are vulnerable to ferroptosis induction. Our results have shown that xCT (SLC7A11) was overexpressed in malignant tissues obtained from the patients with HNSCC, whereas normal mucosa demonstrated weak expression of the protein. In order to investigate the role of Erk1/2 in the decrease in cell viability caused by erastin, xCT-overexpressing FaDu and SCC25 HNSCC cells were used. The ravoxertinib-dependent inhibition of Erk1/2 signaling led to the decrease in erastin efficacy due to the effect on ROS production and the upregulation of ROS scavengers SOD1 and SOD2, resulting in repressed lipid peroxidation. Therefore, it was concluded that the erastin-dependent activation of ferroptosis seems to be a promising approach which can be further developed as an additional strategy for the treatment of HNSCC. As ferroptosis induction via erastin is strongly dependent on the expression of Erk1/2, this MAP kinase can be considered as a predictor for cancer cells’ response to erastin.

This study aimed to characterize the antitumor activity of 5-Chloro-N-{2-[2-(4-chloro-phenyl)-3-methyl-butoxy]-5-trifluoromethyl-phenyl}-2-hydroxy-benzamide (CTFB), a novel anticancer agent, in head and neck cancer cell lines, FaDu, SCC-25 and cisplatin-resistant CAL-27. CTFB was generated as a result of an extensive medicinal chemistry effort on a lead compound series discovered in a high-throughput screen for inducers of apoptosis. All cell lines showed significant growth delay in response to CTFB treatment at a concentration of 1 μmol/L with 17.16 ± 2.08%, 10.92 ± 1.22%, and 27.03 ± 1.86% of cells surviving at 120 h in FaDu, CAL-27, and SCC-25, respectively. To define proteins involved in the mechanism of action of CTFB, we determined differences in the proteome profile of cell lines before and after treatment with CTFB using two-dimensional difference gel electrophoresis followed by computational image analysis and mass spectrometry. Eight proteins were found to be regulated by CTFB in all cell lines. All these proteins are involved in cytoskeleton formation and function and/or in cell cycle regulation. We showed that CTFB-induced cell growth delay was accompanied by cell cycle arrest at the G₀-G₁ phase that was associated with the up-regulation of p21/WAF1 and p27/Kip1 expression and the down-regulation of cyclin D1. Furthermore, we showed that activity of CTFB depended on the down-regulation of nuclear factor-κB (NF-κB) and NF-κB p65 phosphorylated at Ser⁵³⁶. The level of proteasome activity correlated with the response to CTFB treatment, and the down-regulation of NF-κB is accompanied by enhanced proteasome activity in all investigated head and neck cancer cell lines. In this report, we show that CTFB reveals multiple effects that lead to delayed cell growth. Our data suggest that this compound should be studied further in the treatment of head and neck cancer. [Mol Cancer Ther 2007;6(6):1898–908]

This study aims to investigate the effect of dose escalation with brachytherapy (BT) as an addition to definitive chemoradiotherapy (CRT) on local control and survival in esophageal cancer. From 2001 to 2020, 183 patients with locally limited or locally advanced esophageal cancer received definitive CRT with or without brachytherapy in a two-center study. External-beam radiotherapy was delivered at 50.4 Gy in 1.8 Gy daily fractions, followed by a sequential boost to the primary tumor of 9 Gy in 1.8 Gy daily fractions if indicated. Intraluminal high dose rate (HDR) Ir-192 brachytherapy was performed on 71 patients at 10 Gy in two fractions, with one fraction per week. The combined systemic therapy schedules used included 5-fluorouracil/cisplatin or 5-fluorouracil alone. Cisplatin was not administered in patients receiving brachytherapy. The median local progression-free survival was significantly extended in the BT group (18.7 vs. 6.0 months; p < 0.0001), and the median local control was also significantly prolonged (30.5 vs. 11.3 months, p = 0.008). Overall survival (OS) significantly increased in the BT group (median OS 22.7 vs. 9.1 months, p < 0.0001). No significant difference in the overall rate of acute toxicities was observed; however, the rate of acute esophagitis was significantly higher in the BT group (94.4% vs. 81.2%). Likewise, the overall rate of late toxicities (43.7% vs. 18.8%) was significantly higher in the BT group, including the rate of esophageal stenosis (22.5% vs. 9.8%). There was no difference in the occurrence of life-threatening or lethal late toxicities (grades 4 and 5). Brachytherapy, after chemoradiation with single-agent 5-FU, represents a safe and effective alternative for dose escalation in the definitive treatment of esophageal cancer.