Amr Ali

In non-small cell lung cancer (NSCLC), radiotherapy not only mediates cytotoxicity but also activates radioresistance drivers like HER2. We investigated radiotherapy combined with HER2-targeted T cell therapy in an NSCLC model. The antitumor efficacy of radiotherapy and engineered T cells expressing a DAP12-associated synthetic antigen receptor (SAR) targeting HER2 was evaluated in HER2-expressing A549 xenografts. HER2 modulation, transcriptional regulation, and tumor T cell infiltration were assessed using immunoblotting, real-time quantitative polymerase chain reaction, flow cytometry, RNA-seq, and immunohistochemistry. High-dose HER2-SAR T cell infusion abolished A549 tumor growth but induced graft-vs-host disease. Low-dose T cell infusion was well-tolerated and provided partial tumor inhibition. Induction radiotherapy (7 d before T cell infusion) synergistically improved tumor control and survival. Radiotherapy transiently upregulated HER2 expression (4 to 24 h), though administering HER2-SAR T cells within this window did not enhance antitumor efficacy. Radiation did not enhance T cell-mediated cytotoxicity in vitro. However, in tumors, radiotherapy increased intratumoral proliferation and accumulation of HER2-SAR T cells and enhanced the extrinsic apoptotic pathway, including induction of Fas transcript and protein levels and cleaved caspase-3 (CC3). RNA-seq of irradiated tumors revealed lasting transcriptional reprogramming with increased immune activation and decreased proliferation and oncogenic signaling. Induction radiotherapy enhances HER2-SAR T cell infiltration and provides synergistic tumor suppression, likely through additional activation of immune-mediated apoptosis. These findings support further assessment of HER2-SAR T cell therapy in HER2-expressing NSCLC.

Radiotherapy is a non-invasive standard treatment for prostate cancer (PC). However, PC develops radio-resistance, highlighting a need for agents to improve radiotherapy response. Canagliflozin, an inhibitor of sodium-glucose co-transporter-2, is approved for use in diabetes and heart failure, but is also shown to inhibit PC growth. However, whether canagliflozin can improve radiotherapy response in PC remains unknown. Here, we show that well-tolerated doses of canagliflozin suppress proliferation and survival of androgen-sensitive and insensitive human PC cells and tumors and sensitize them to radiotherapy. Canagliflozin blocks mitochondrial respiration, promotes AMPK activity, inhibits the MAPK and mTOR-p70^S6k/4EBP1 pathways, activates cell cycle checkpoints, and inhibits proliferation in part through HIF-1α suppression. Canagliflozin mediates transcriptional reprogramming of several metabolic and survival pathways known to be regulated by ETS and E2F family transcription factors. Genes downregulated by canagliflozin are associated with poor PC prognosis. This study lays the groundwork for clinical investigation of canagliflozin in PC prevention and treatment in combination with radiotherapy.

Non‐small cell lung cancer (NSCLC) has a poor prognosis, and effective therapeutic strategies are lacking. The diabetes drug canagliflozin inhibits NSCLC cell proliferation and the mammalian target of rapamycin (mTOR) pathway, which mediates cell growth and survival, but it is unclear whether this drug can enhance response rates when combined with cytotoxic therapy. Here, we evaluated the effects of canagliflozin on human NSCLC response to cytotoxic therapy in tissue cultures and xenografts. Ribonucleic acid sequencing (RNA‐seq), real‐time quantitative PCR (RT‐qPCR), metabolic function, small interfering ribonucleic acid (siRNA) knockdown, and protein expression assays were used in mechanistic analyses. We found that canagliflozin inhibited proliferation and clonogenic survival of NSCLC cells and augmented the efficacy of radiotherapy to mediate these effects and inhibit NSCLC xenograft growth. Canagliflozin treatment alone moderately inhibited mitochondrial oxidative phosphorylation and exhibited greater antiproliferative capacity than specific mitochondrial complex‐I inhibitors. The treatment downregulated genes mediating hypoxia‐inducible factor (HIF)‐1α stability, metabolism and survival, activated adenosine monophosphate‐activated protein kinase (AMPK) and inhibited mTOR, a critical activator of hypoxia‐inducible factor‐1α (HIF‐1α) signaling. HIF‐1α knockdown and stabilization experiments suggested that canagliflozin mediates antiproliferative effects, in part, through suppression of HIF‐1α. Transcriptional regulatory network analysis pinpointed histone deacetylase 2 (HDAC2), a gene suppressed by canagliflozin, as a key mediator of canagliflozin's transcriptional reprogramming. HDAC2 knockdown eliminated HIF‐1α levels and enhanced the antiproliferative effects of canagliflozin. HDAC2‐regulated genes suppressed by canagliflozin are associated with poor prognosis in several clinical NSCLC datasets. In addition, we include evidence that canagliflozin also improves NSCLC response to chemotherapy. In summary, canagliflozin may be a promising therapy to develop in combination with cytotoxic therapy in NSCLC.

Gasotransmitters are small molecules of gases, including nitric oxide (NO), hydrogen sulfide (H₂S), and carbon monoxide (CO). These three gasotransmitters can be endogenously produced and regulate a wide range of pathophysiological processes by interacting with specific targets upon diffusion in the biological media. By redox and epigenetic of various physiological functions, NO, H₂S, and CO are critical for maintenance of intracellular energy homeostasis. Accumulated evidence has shown that these three gasotransmitters control ATP generation, mitochondrial biogenesis, glucose metabolism, insulin sensitivity, lipid metabolism, and thermogenesis, etc. Abnormal generation and metabolism of NO, H₂S, and/or CO are involved in various abnormal metabolic diseases, including obesity, diabetes, and dyslipidemia. In this review, we summarized the roles of NO, H₂S, and CO in the regulation of energy homeostasis as well as their involvements in the metabolism dysfunction-related diseases. Understanding the interaction among these gasotransmitters and their specific molecular targets are very important for therapeutic applications.