Epidermal growth factor potentiates EGFR(Y992/1173)-mediated therapeutic response of triple negative breast cancer cells to cold atmospheric plasma-activated medium

Cancer metastasis: molecular mechanisms and therapeutic interventions

The metastatic cascade is a complicated process where cancer cells travel across multiple organs distant from their primary site of onset. Despite the wide acceptance of the 'seed and soil' theory, mechanisms driving metastasis organotropism remain mystery. Using breast cancer of different subtypes as the disease model, we characterized the 'metastatic profile of cancer cells' and the 'redox status of the organ microenvironment' as the primary determinants of cancer metastasis organotropism. Mechanically, we identified a positive correlation between cancer metabolic plasticity and stemness, and proposed oxidative stress as the selection power of cancer cells succeeding the metastasis cascade. Therapeutically, we proposed the use of pro-oxidative therapeutics in ablating cancer cells taking advantages of this fragile moment during metastasis. We comprehensively reviewed current pro-oxidative strategies for treating cancers that cover the first line chemo- and radio-therapies, approaches relying on naturally existing power including magnetic field, electric field, light and sound, nanoparticle-based anti-cancer composites obtained through artificial design, as well as cold atmospheric plasma as an innovative pro-oxidative multi-modal modality. We discussed possible combinations of pro-oxidative approaches with existing therapeutics in oncology prior to the forecast of future research directions. This paper identified the fundamental mechanics driving metastasis organotropism and proposed intervention strategies accordingly. Insights provided here may offer clues for the design of innovative solutions that may open a new paradigm for cancer treatment.

Innovative Therapeutic Approach Targeting Colon Cancer Stem Cells: Transitional Cold Atmospheric Plasma

Transitional cold atmospheric plasma (TCAP) represents a novel technique for generating plasma remotely from a primary source. It consists of a partially nonthermal ionized gas mixture containing charged and neutral particles, photons, and free radicals. In recent years, TCAP has attracted considerable attention in biomedical applications. In order to evaluate colon cancer stem cells' (CCSCs) proliferation, apoptotic induction, inflammatory response, and survival, TCAP was utilized both directly and indirectly in this study. Using argon and helium gases, TCAP was continuously delivered in two stages during the experiment. For direct state, TCAP was irradiated onto CCSCs for 3 and 5 min. In the indirect technique, Matrigel was treated with TCAP for 5 min before the introduction of cells. In vitro assays demonstrated that TCAP exposure significantly reduced the viability of CCSCs; helium gas and direct application had greater impacts than argon. Numerous investigations confirmed the induction of apoptosis, showing that the treated groups had more apoptotic cells and altered cellular structures than controls (****p < 0.0001). A substantial increase in the Bax/Bcl-2 ratio was found by analyzing the expression of the Bax and Bcl-2 genes, indicating increased susceptibility to apoptosis (*p = 0.0177 and ***p = 0.0004). The higher efficacy of the direct helium mode was further highlighted by inflammatory marker analysis, which showed a significant reduction in interleukin-6 and interleukin-8 expression in cells directly treated with TCAP-helium compared to TCAP-argon (**p = 0.0015 and ***p = 0.0007). Lastly, the proliferation test, which relies on K i-67 expression, demonstrated a noteworthy decline in all TCAP-treated groups, with the direct helium group exhibiting the most robust impact (**p = 0.0014). Overall, the findings highlight the potential of TCAP, particularly with helium, as a promising approach for selectively targeting CCSCs and providing insights into its therapeutic mechanisms for cancer treatment. TCAP, therefore, emerges as a unique therapeutic strategy with potential applications in cancer stem cell-targeted therapies.

Cold atmospheric plasma control metabolic syndromes via targeting fat mass and obesity-associated protein

Both obesity and metabolic disorders are global medical problems. Driven by prolonged inflammation, obesity increases the risk of developing metabolic syndromes such as fatty liver, diabetes, cardiovascular diseases and cancers. The fat mass and obesity-associated protein (FTO) is an m6A demethylase, elevated activity of which is known to promote the pathogenesis of many metabolic disorders, leading to the establishment of various FTO inhibitors. By combing through intrinsic connections among obesity and the four primary metabolic problems, we attribute their shared pathological cause to prolonged inflammation. By reviewing the roles of FTO in promoting these disorders and the current status of existing FTO inhibitors in treating these syndromes, we underpinned the paramount potential of resolving these clinical issues by targeting FTO and the urgent need of establishing novel FTO inhibitors with maximized efficacy and minimized side effect. Cold atmospheric plasma (CAP) is the fourth state of matter with demonstrated efficacy in treating various diseases associated with chronic inflammation. By introducing the medical characteristics of CAP, we proposed it as a possible solution to unresolved issues of current FTO inhibitors given its anti-inflammation feature and demonstrated clinical safety. We also emphasized the need of intensive investigations in exploring the feasibility of using CAP in treating obesity and associated metabolic syndromes that might function through targeting FTO.

Cold atmospheric plasma potentiates ferroptosis via EGFR(Y1068)-mediated dual axes on GPX4 among triple negative breast cancer cells

Cold atmospheric plasma (CAP) has been proposed as an emerging onco-therapeutics that can specifically kill cancer cells without harming healthy cells. Here we explore its potency in triggering ferroptosis in transformed cells using triple negative breast cancer as the disease model. Through the whole transcriptome sequencing, mass spectrometry analysis, point mutation, and a series of in vitro and in vivo molecular assays, we identified two signaling axes centered at EGFR(Y1068), i.e., EGFR-TRIM25-KEAP1/SIAH2-NRF2 and EGFR-p38-NRF2, which suppressed GPX4 at both transcriptional and translational levels. We, in addition, demonstrated the potency of CAP in synergizing with Sorafenib towards enhanced selectivity against cancer cells via initiating ferroptosis. We are the first to systematically clarify the molecular mechanism of GPX4-dependent ferroptosis induced by CAP, and propose the feasibility of activating EGFR instead of suppressing it as well as the benefits of resolving tumors by coupling CAP with ferroptosis-inducing agents. The identified signaling axis is applicable to all cancers harboring EGFR that deserve intensive investigations.

Metal-organic frameworks: potential synergies with cold atmospheric plasmas for cancer control

Metal-organic frameworks (MOFs) have attracted increasing attention for cancer treatment due to their unique characteristics such as crystallized porous structures, high surface area, and diverse and modifiable chemical properties. Despite the plethora of reports on MOF-based onco-therapeutic designs, these nanocomposites have rarely been launched for clinical use, given, at least, one unavoidable concern, i.e., biosafety. Among the diverse possibilities that MOFs can be engaged for cancer treatment, one unignorable opportunity is how MOFs can be combined with other emerging anti-cancer approaches as one treatment modality to resolve issues of either one for surpassed treatment efficacy. Taking cold atmospheric plasmas (CAPs) as an example, this review delineates the unique features of MOFs and discusses the possible synergies they can create with CAPs for mutual benefits. By providing one example on how MOFs can help overcome the issues of other pre-clinical cancer treatment regimens, this review identifies one research niche that may thrive the field of plasma medicine and revolutionize the schema of MOFs for biological applications.

Multiple RONS-Loaded Plasma-Activated Ice Microneedle Patches for Transdermal Treatment of Psoriasis

Cold atmospheric plasma (CAP) is a fledgling therapeutic technique for psoriasis treatment with noninvasiveness, but clinical adoption has been stifled by the insufficient production and delivery of plasma-generated reactive oxygen and nitrogen species (RONS). Herein, patches of air-discharge plasma-activated ice microneedles (PA-IMNs) loaded with multiple RONS are designed for local transdermal delivery to treat psoriasis as an alternative to direct CAP irradiation treatment. By mixing two RONS generated by the air-discharge plasma in the NOx mode and O3 mode, abundant high-valence RONS are produced and incorporated into PA-IMNs via complex gas-gas and gas-liquid reactions. The PA-IMNs abrogate keratinocyte overproliferation by inducing reactive oxygen species (ROS)-mediated loss of the mitochondrial membrane potential and apoptosis of keratinocytes. The in vivo transdermal treatment confirms that PA-IMNs produce significant anti-inflammatory and therapeutic actions for imiquimod (IMQ)-induced psoriasis-like dermatitis in mice by inhibiting the release of associated inflammatory factors while showing no evident systemic toxicity. Therefore, PA-IMNs have a large potential in transdermal delivery platforms as they overcome the limitations of using CAP directly in the clinical treatment of psoriasis.

Cold atmospheric plasma enhances SLC7A11-mediated ferroptosis in non-small cell lung cancer by regulating PCAF mediated HOXB9 acetylation

Lung cancer is a leading cause of cancer death worldwide, with high incidence and poor survival rates. Cold atmospheric plasma (CAP) technology has emerged as a promising therapeutic approach for cancer treatment, inducing oxidative stress in malignant tissues without causing thermal damage. However, the role of CAP in regulating lung cancer cell ferroptosis remains unclear. Here, we observed that CAP effectively suppressed the growth and migration abilities of lung cancer cells, with significantly increased ferroptotic cell death, lipid peroxidation, and decreased mitochondrial membrane potential. Mechanistically, CAP regulates SLC7A11-mediated cell ferroptosis by modulating HOXB9. SLC7A11, a potent ferroptosis suppressor, was markedly reduced by HOXB9 knockdown, while it was enhanced by overexpressing HOXB9. The luciferase and ChIP assays confirmed that HOXB9 can directly target SLC7A11 and regulate its gene transcription. Additionally, CAP enhanced the acetylation modification level of HOXB9 by promoting its interaction with acetyltransferase p300/CBP-associated factor (PCAF). Acetylated HOXB9 affects its protein ubiquitination modification level, which in turn affects its protein stability. Notably, the upregulation of SLC7A11 and HOXB9 mitigated the suppressive effects of CAP on ferroptosis status, cell proliferation, invasion, and migration in lung cancer cells. Furthermore, animal models have also confirmed that CAP can inhibit the progression of lung cancer in vivo. Overall, this study highlights the significance of the downregulation of the HOXB9/SLC7A11 axis by CAP treatment in inhibiting lung cancer, offering novel insights into the potential mechanisms and therapeutic strategies of CAP for lung cancer.

Effects of N361 Glycosylation on Epidermal Growth Factor Receptor Biological Function

Epidermal growth factor receptor (EGFR) is a transmembrane tyrosine kinase that is frequently modified by glycosylation post-translationally. In cancer, EGFR amplifications and hotspot mutations such as L858R that promote proliferation have been detected in a significant fraction of non-small cell lung carcinomas and breast adenocarcinomas. Molecular dynamic simulations suggested that glycosylation at asparagine residue 361 (N361) promotes dimerization and ligand binding. We stably expressed glycosylation-deficient mutant EGFR N361A, with or without the oncogenic mutation L858R. Immunofluorescence and flow cytometry demonstrated that the mutants were each well expressed at the cell membrane. N361A decreased proliferation relative to wild-type EGFR as well as decreased sensitivity to ligands. Proximity ligation assays measuring co-localization of EGFR with its binding partner HER2 in cells revealed that N361A mutations increased co-localization. N361A, located near the binding interface for the EGFR inhibitor necitumumab, desensitized cells expressing the oncogenic EGFR L858R to antibody-based inhibition. These findings underline the critical relevance of post-translational modifications on oncogene function.