Coralyne Radiosensitizes A549 Cells by Upregulation of CDKN1A Expression to Attenuate Radiation Induced G2/M Block of the Cell Cycle

Copper(II) complex with 1-allylimidazole induces G2/M cell cycle arrest and suppresses A549 cancer cell growth by attenuating Wnt, JAK-STAT, and TGF-β signaling pathways

The main aim of the study was to investigate the molecular mechanism of action of the potentially anti-cancer agent copper(II) complex with 1-allylimidazole [Cu(1-allim)4(NO3)2] using the A549 lung cancer line, toward which it is selectively cytotoxic. Gene expression analysis showed that the complex caused apoptosis through WNT, JAK-STAT, and TGF-β pathways. The complex induced DNA damage, ROS production, and depolarization of the mitochondrial membrane, suggesting that its toxicity is likely due to induction of the intrinsic apoptosis pathway. It also arrested the cell cycle at G2/M phase. Particularly noteworthy is that it inhibited the WNT pathway, a target for lung cancer therapies. Its complex mechanism of action may hinder the acquisition of immunity by cancer cells.

Dietary Methionine Restriction Alleviates Cognitive Impairment in Alzheimer's Disease Mice via Sex-Dependent Modulation on Gut Microbiota and Tryptophan Metabolism: A Multiomics Analysis

Plant-based foods with low methionine contents have gained increasing interest for their potential health benefits, including neuroprotective effects. Methionine restriction (MR) linked to a plant-based diet has been shown to mitigate neurodegenerative diseases such as Alzheimer's disease (AD) through mechanisms that involve the gut microbiota. In this study, a 16-week MR diet (0.17% methionine, w/w) improved working memory and reduced neuronal damage exclusively in 4-month-old male APP/PS1 AD mice. Transcriptomic analysis revealed the activation of serum- and glucose-corticoid-regulated kinase 1 (SGK1) and peroxisome proliferator-activated receptor α (PPARα) pathways. Furthermore, metabolomics demonstrated increased serum indole-3-propionic acid (IPA) levels and an enhanced expression of gut barrier proteins Claudin-1 and MUC2 in male mice. MR significantly altered the gut microbiota composition, notably increasing indole-producing bacteria such as Lactobacillus reuteri (L. reuteri). Multiomics integration linked L. reuteri, IPA, and PPARα signaling to improved cognitive outcomes. Molecular docking and RT-qPCR analyses confirmed IPA's interaction with PPARα, leading to the activation of neuroprotective targets (Bdnf, Pparα, Acsbg1, Scd2, and Scd3). These results highlight the role of methionine restriction in modulating gut microbiota and metabolites, offering a promising dietary approach to managing neurodegenerative diseases with sex-specific effects.

Coralyne Targets the Catalytic Domain of MMP9: An In Silico and In Vitro Investigation

Coralyne (COR) is a protoberberine-like isoquinoline alkaloid, and it is known for double-stranded (ds) DNA intercalation and topoisomerase inhibition. It can also sensitize cancer cells through various mechanisms. COR reduces the proliferation and migration of breast cancer cells by inhibiting the expression and activity of matrix metalloproteinase 9 (MMP9). However, the mechanism involved in the inhibitory activity of COR on MMP9 is not known. In the present study, in silico docking studies showed that COR binds to the active site of MMP9 catalytic domain (MMP9-CD) with considerable affinity. The binding affinity of COR to the MMP9-CD, estimated by three different web servers: CB Dock, Seam Dock, and PyRx, was found to be either -7.4 or -7.5 kcal/mol. Another web server that is routinely used for docking studies, Docking Server, has predicted a binding affinity of -5.9 kcal/mol. All four docking servers predicted the same binding site for COR within the MMP9-CD. Corroborating our docking results, molecular dynamic simulation studies have also shown that COR interacts with the same key active site amino acid residues of the MMP9-CD that are essential for its proteolytic function. Molecular mechanics with generalized born and surface area (MMGBSA) calculations using Schrodinger's prime module have shown that the binding free energy with which COR binds to MMP9 is -50 kcal/mol. It inhibited activity of recombinant human MMP9 activity and induced significant cytotoxicity and reduced the proliferation of MDA-MB 468 cells. Overall, our in silico and in vitro experiments show that COR potentially inhibits the activity of MMP9 by directly binding to the active site of its catalytic domain and possibly inhibits proliferation of MDA-MB 468 cells.

Blue light photobiomodulation induced osteosarcoma cell death by facilitating ferroptosis and eliciting an incomplete tumor cell stress response

To investigate the potential of blue light photobiomodulation (PBM) in inducing ferroptosis, a novel form of regulated cell death, in OS cells, considering its known effectiveness in various cancer models. In this investigation, we exposed human OS cell lines, HOS and MG63, to different wavelengths (420, 460 and 480 nm) of blue light at varying irradiances, and examined cellular responses such as viability, apoptosis, levels of reactive oxygen species (ROS), and mitochondrial membrane potential (MMP). Transcriptome sequencing was employed to unravel the molecular mechanisms underlying blue light-induced effects, with validation via quantitative real-time PCR (qRT-PCR). Our findings revealed a wavelength- and time-dependent decrease in cell viability, accompanied by increased apoptosis and oxidative stress. Transcriptomic analysis identified differential expression of genes associated with ferroptosis, oxidative stress, and iron metabolism, further validated by qRT-PCR. These results implicated ferroptosis as a significant mechanism in the blue light-induced death of OS cells, potentially mediated by ROS generation and disruption of iron homeostasis. Also, An incomplete stress response was observed in MG63 cells induced by blue light exposure. Hence, blue light PBM holds promise as a therapeutic approach in OS clinical investigations; however, additional exploration of its underlying mechanisms remains imperative.

Integration of G-Quadruplex and Pyrene as a Simple and Efficient Ratiometric Fluorescent Platform That Programmed by Contrary Logic Pair for Highly Sensitive and Selective Coralyne (COR) Detection

The effective and accurate detection of the anticancer drug coralyne (COR) is highly significant for drug quality control, medication safety and good health. Although various COR sensors have been reported in recent years, previous ones can only exhibit single-signal output (turn ON or turn OFF) with poor reliability and anti-interference ability. Therefore, exploring novel platform with dual-signal response for COR detection is urgently needed. Herein, we reported the first ratiometric fluorescent platform for highly sensitive and selective COR detection by integrating G-quadruplex (G4) and Pyrene (Py) as signal probes and harnessing A-COR-A interaction. In the absence of COR, the platform shows a low fluorescence signal of PPIX (F₆₄₂) and a high one of Py monomer (F₃₈₃). With the addition of COR, two delicately designed poly-A ssDNAs will hybridize with each other via A-COR-A coordination to form complete G4, yielding the increased fluorescence signal of PPIX and the decreased one of Py due to the formation of Py excimer. Based on the above mechanism, we constructed a simple and efficient sensor that could realize the ratiometric fluorescent detection of COR with high sensitivity and selectivity. A linear relationship between F₆₄₂/F₃₈₃ and COR's concentration is obtained in the range from 1 nM to 8 μM. And the limit of detection of COR could reach to as low as 0.63 nM without any amplification, which is much lower than that of most COR sensors reported so far. Notably, the logical analysis of COR can be carried out under the control of a "YES-NOT" contrary logic pair, enabling the smart dual-channel response with an adequate S/N ratio and improved reliability and anti-interference ability. Moreover, this system also presents satisfactory performance in fetal bovine serum (FBS) samples.

Recent advancements in coralyne (COR)-based biosensors: Basic principles, various strategies and future perspectives

As a kind of protoberberine alkaloid heterocyclic analogues, coralyne (COR) has been reported to exhibit superior antileukemic ability and used as anticancer drug agent. While, the severe hazards and side effects caused by unreasonable use have made its accurate detection more and more important. Although scientists have explored various methods to sense COR and other related targets, a systematical review which could not only elaborate recent developments and analyze current challenges of COR-based biosensors, but also present future perspective has not been reported and is urgently needed. In this review, we attempt to summarize latest advancements in COR-based biosensors in recent decade. Firstly, the operating principles, advantages and disadvantages of various strategies for COR detection (colorimetric, fluorescent, electrochemical and other ones) are comprehensively demonstrated and reviewed. Secondly, COR-assisted biosensors for detection of different non-COR targets (heparin, toxins, nucleic acids and other small molecules) are further discussed. Finally, we analyze current challenges and also suggest potential perspectives for this area.

KLK5 is associated with the radioresistance, aggression, and progression of cervical cancer

OBJECTIVE

The role of kallikrein-related peptidase 5 (KLK5) has been studied in several diseases, including skin and ovarian cancers. However, its role in cervical cancer remains unclear, particularly in regulating the radiation resistance and growth of cervical cancer cells. Radiation resistance of cervical cancer is associated with local recurrence, distant metastasis, and reduced survival.

METHODS

We first analyzed radiotherapy-naive samples and relevant clinical data from patients with cervical cancer who received radiotherapy without surgery or other antitumor treatment from 2014 to 2016. Subsequently, biopsied tissues, in vitro cells, and transplanted tumors in nude mice were investigated.

RESULTS

Gene sequencing and clinical data analysis showed that KLK5 overexpression was associated with a poor prognosis post-radiotherapy. In in vitro cell and tumor transplantation experiments, KLK5 overexpression significantly increased radiation resistance. However, downregulating KLK5 expression increased radiosensitivity.

CONCLUSION

Our results confirm that KLK5 is vital to the radioresistance of cervical cancer, and provide a new target and marker for the treatment of radioresistance in cervical cancer.

Hypothermia differentially modulates the formation and decay of NBS1, γH2AX and 53BP1 foci in U2OS cells exposed to gamma radiation

In studies on the mechanism of DNA damage response where ionizing radiation is used as the DNA damaging agent, cells are often exposed to ionizing radiation on melting ice (corresponding to 0.8 °C). The purpose of this procedure is to inhibit cellular processes i.e. DNA repair. Low temperature at exposure has been shown to act in a radioprotective manner at the level of cytogenetic damage, but its mechanisms of action are poorly understood. The aim of the study was to analyze the effect of hypothermia at the level of formation and decay of NBS1, γH2AX, and 53BP1 foci, micronuclei, survival, cell cycle progression and oxidative stress in U2OS cells. The results show that hypothermia alone induced oxidative stress and foci. When applied in combination with radiation but only during the exposure time, it potentiated the formation of γH2AX and 53BP1 but not of NBS1 foci. When applied during irradiation and subsequent repair time, 53BP1 and NBS1 foci formed and decayed, but the levels were markedly lower than when repair was carried out at 37 °C. The frequency of micronuclei was elevated in cells irradiated at 0.8 °C, but only when analysed 20 h after irradiation which is likely due to a reduced G₂ cell cycle block. Hypothermia reduced cell survival, both with and without radiation exposure. The temperature effect should be considered when cooling cells on melting ice to inhibit DNA repair in the induction of DNA damage.