Caspase-7: a protease involved in apoptosis and inflammation

BM7, a derivative of benzofuran, effectively fights cancer by promoting cancer cell apoptosis and impacting IL-6 levels

The BM7 compound, a bromo derivative of methyl 6-acetyl-5-hydroxy-2-methyl-1-benzofuran-3-carboxylate, was previously identified as cytotoxic to human leukaemia cells (K562 and HL60) and human cervical cancer (HeLa), while showing no toxicity to non-cancerous primary endothelial cells (HUVEC). In this study, we present the first demonstration of BM7's anticancer efficacy in vivo using a mouse chronic myeloid leukaemia xenograft model. Administered intraperitoneally in a mixture of 10% Solutol HS 15/10% ethanol, BM7 exhibited no visible toxicity and significantly reduced tumor weight, comparable to standard drugs imatinib and hydroxyurea. Further supporting its anticancer potential, a multi-model in vitro study involving seven human cancer cell lines revealed the most promising responses in colon cancer (SW480, SW620, HCT116), liver cancer (HEPG2), and breast adenocarcinoma (MDA-MB-231) cells. BM7 demonstrated multifaceted anticancer mechanisms, inducing apoptosis while elevating reactive oxygen species (ROS) levels and suppressing interleukin-6 (IL-6) release in these cell lines. These findings position BM7 as a candidate of significant interest for cancer therapy. Its ability to not only induce apoptosis but also modulate cellular processes such as ROS levels and immune responses, specifically IL-6 suppression, makes BM7 a versatile and promising agent for further exploration in the realm of cancer treatment.

Astrocyte Mitochondria Are a Sensitive Target of PCB52 and its Human-Relevant Metabolites

Polychlorinated biphenyls (PCBs) are industrial chemicals that are ubiquitously found in the environment. Exposure to these compounds has been associated with neurotoxic outcomes; however, the underlying mechanisms for such outcomes remain to be fully understood. Recent studies have shown that astrocytes, the most abundant glial cell type in the brain, are susceptible to PCB exposure as well as exposure to human-relevant metabolites of PCBs. Astrocytes are critical for maintaining healthy brain function due to their unique functional attributes and positioning within the neuronal networks in the brain. In this study, we assessed the toxicity of PCB52, one of the most abundantly found PCB congeners in outdoor and indoor air, and two of its human-relevant metabolites, on astrocyte mitochondria. We exposed C6 cells, an astrocyte cell line, to PCB52 or its human-relevant metabolites and found that all the compounds showed increased toxicity in galactose-containing media compared to that in the glucose-containing media, indicating the involvement of mitochondria in observed toxicity. Additionally, we also found increased oxidative stress upon exposure to PCB52 metabolites. All three compounds caused a loss of mitochondrial membrane potential, distinct changes in the mitochondrial structure, and impaired mitochondrial function. The hydroxylated metabolite 4-OH-PCB52 likely functions as an uncoupler of mitochondria. This is the first study to report the adverse effects of exposure to PCB52 and its human-relevant metabolites on the mitochondrial structure and function in astrocytes.

Ssc-miR-7139-3p suppresses foot-and-mouth disease virus replication by promoting degradation of 3Cpro through targeting apoptosis-negative regulatory gene Bcl-2

Foot-and-mouth disease is a highly contagious and infectious disease affecting cloven-hoofed animals. Disease control is complicated by its highly contagious nature and antigenic diversity. Host microRNAs (miRNAs) are post-transcriptional regulators that either promote or repress viral replications in virus infection. In the present study, we found that ssc-miR-7139-3p (Sus scrofa miR-7139-3p) was significantly up-regulated in host cells during foot-and-mouth disease virus (FMDV) infection. Overexpression of miR-7139-3p attenuated FMDV replication, whereas inhibition promoted FMDV replication. In addition, the survival rate of FMDV infected suckling mice was increased through injection of miR-7139-3p agomiR. Further studies revealed that miR-7139-3p targets Bcl-2 to initiate the apoptotic pathway and caspase-3 cleaved 3Cpro behind the 174th aspartic acid (D174), which eventually promotes the degradation of 3Cpro. Overall, our findings demonstrate that miR-7139-3p suppresses FMDV replication by promoting degradation of 3Cpro through targeting the apoptosis-negative regulatory gene Bcl-2.

Co-delivery of artemisinin and metformin via PEGylated niosomal nanoparticles: potential anti-cancer effect in treatment of lung cancer cells

PURPOSE

Despite the advances in treatment, lung cancer is a global concern and necessitates the development of new treatments. Biguanides like metformin (MET) and artemisinin (ART) have recently been discovered to have anti-cancer properties. As a consequence, in the current study, the anti-cancer effect of MET and ART co-encapsulated in niosomal nanoparticles on lung cancer cells was examined to establish an innovative therapy technique.

METHODS

Niosomal nanoparticles (Nio-NPs) were synthesized by thin-film hydration method, and their physicochemical properties were assessed by FTIR. The morphology of Nio-NPs was evaluated with FE-SEM and AFM. The MTT assay was applied to evaluate the cytotoxic effects of free MET, free ART, their encapsulated form with Nio-NPs, as well as their combination, on A549 cells. Apoptosis assay was utilized to detect the biological processes involved with programmed cell death. The arrest of cell cycle in response to drugs was assessed using a cell cycle assay. Following a 48-h drug treatment, the expression level of hTERT, Cyclin D1, BAX, BCL-2, Caspase 3, and 7 genes were assessed using the qRT-PCR method.

RESULTS

Both MET and ART reduced the survival rate of lung cancer cells in the dose-dependent manner. The IC50 values of pure ART and MET were 195.2 μM and 14.6 mM, respectively while in nano formulated form their IC50 values decreased to 56.7 μM and 78.3 μM, respectively. The combination of MET and ART synergistically decreased the proliferation of lung cancer cells, compared to the single treatments. Importantly, the combination of MET and ART had a higher anti-proliferative impact against A549 lung cancer cells, with lower IC50 values. According to the result of Real-time PCR, hTERT, Cyclin D1, BAX, BCL-2, Caspase 3, and Caspase 7 genes expression were considerably altered in treated with combination of nano formulated MET and ART compared to single therapies.

CONCLUSION

The results of this study showed that the combination of MET and ART encapsulated in Nio-NPs could be useful for the treatment of lung cancer and can increase the efficiency of lung cancer treatment.

Bacterial heat shock protein: A new crosstalk between T lymphocyte and macrophage via JAK2/STAT1 pathway in bloodstream infection

Bloodstream infection (BSI) refers to the infection of blood by pathogens. Severe immune response to BSI can lead to sepsis, a systemic infection leading to multiple organ dysfunction, coupled with drug resistance, mortality, and limited clinical treatment options. This work aims to further investigate the new interplay between bacterial exocrine regulatory protein and host immune cells in the context of highly drug-resistant malignant BSI. Whether interfering with related regulatory signaling pathways can reverse the inflammatory disorder of immune cells. In-depth analysis of single-cell sequencing results in Septic patients for potential immunodeficiency factors. Analysis of key proteins enriched by host cells and key pathways using proteomics. Cell models and animal models validate the pathological effects of DnaK on T cells, MAITs, macrophages, and osteoclasts. The blood of patients was analyzed for the immunosuppression of T cells and MAITs. We identified that S. maltophilia-DnaK was enriched in immunodeficient T cells. The activation of the JAK2/STAT1 axis initiated the exhaustion of T cells. Septic patients with Gram-negative bacterial infections exhibited deficiencies in MAITs, which correspond to IFN-γ. Cellular and animal experiments confirmed that DnaK could facilitate MAIT depletion and M1 polarization of macrophages. Additionally, Fludarabine mitigated M1 polarization of blood, liver, and spleen in mice. Interestingly, DnaK also repressed osteoclastogenesis of macrophages stimulated by RANKL. S.maltophilia-DnaK prompts the activation of the JAK2/STAT1 axis in T cells and the M1 polarization of macrophages. Targeting the DnaK's crosstalk can be a potentially effective approach for treating the inflammatory disorder in the broad-spectrum drug-resistant BSI.

Microarray-based detection and expression analysis of drug resistance in an animal model of peritoneal metastasis from colon cancer

Chemotherapy drugs efficiently eradicate rapidly dividing differentiated cells by inducing cell death, but poorly target slowly dividing cells, including cancer stem cells and dormant cancer cells, in the later course of treatment. Prolonged exposure to chemotherapy results in a decrease in the proportion of apoptotic cells in the tumour mass. To investigate and characterize the molecular basis of this phenomenon, microarray-based expression analysis was performed to compare tHcred2-DEVD-EGFP-caspase 3-sensor transfected C-26 tumour cells that were harvested after engraftment into mice treated with or without 5-FU. Peritoneal metastasis was induced by intraperitoneal injection of C-26 cells, which were subsequently reisolated from omental metastatic tumours after the mice were sacrificed by the end of the 10th day after tumour injection. The purity of reisolated tHcred2-DEVD-EGFP-caspase 3-sensor-expressing C-26 cells was confirmed using FLIM, and total RNA was extracted for gene expression profiling. The validation of relative transcript levels was carried out via real-time semiquantitative RT‒PCR assays. Our results demonstrated that chemotherapy induced the differential expression of mediators of cancer cell dormancy and cell survival-related genes and downregulation of both intrinsic and extrinsic apoptotic signalling pathways. Despite the fact that some differentially expressed genes, such as BMP7 and Prss11, have not been thoroughly studied in the context of chemoresistance thus far, they might be potential candidates for future studies on overcoming drug resistance.

Recombinant Arginine Deiminase from Levilactobacillus brevis Inhibits the Growth of Stomach Cancer Cells, Possibly by Activating the Intrinsic Apoptosis Pathway

The anticancer potential of Levilactobacillus brevis KU15176 against the stomach cancer cell line AGS has been reported previously. In this study, we aimed to analyze the genome of L. brevis KU15176 and identify key genes that may have potential anticancer properties. Among potential anticancer molecules, the role of arginine deiminase (ADI) in conferring an antiproliferative functionality was confirmed. In vitro assay against AGS cell line confirmed that recombinant ADI from L. brevis KU15176 (ADI_br, 5 µg/mL), overexpressed in E. coli BL21 (DE3), exerted an inhibitory effect on AGS cell growth, resulting in a 65.32% reduction in cell viability. Moreover, the expression of apoptosis-related genes, such as bax, bad, caspase-7, and caspase-3, as well as the activity of caspase-9 in ADI_br-treated AGS cells, was higher than those in untreated (culture medium-only) cells. The cell-scattering behavior of ADI_br-treated cells showed characteristics of apoptosis. Flow cytometry analyses of AGS cells treated with ADI_br for 24 and 28 h revealed apoptotic rates of 11.87 and 24.09, respectively, indicating the progression of apoptosis in AGS cells after ADI_br treatment. This study highlights the potential of ADI_br as an effective enzyme for anticancer applications.

Repurposing the diuretic benzamil as an anti-osteosarcoma agent that acts by suppressing integrin/FAK/STAT3 signalling and compromising mitochondrial function

Aims

Osteosarcoma is the most common primary bone malignancy among children and adolescents. We investigated whether benzamil, an amiloride analogue and sodium-calcium exchange blocker, may exhibit therapeutic potential for osteosarcoma in vitro.

Methods

MG63 and U2OS cells were treated with benzamil for 24 hours. Cell viability was evaluated with the MTS/PMS assay, colony formation assay, and flow cytometry (forward/side scatter). Chromosome condensation, the terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay, cleavage of poly-ADP ribose polymerase (PARP) and caspase-7, and FITC annexin V/PI double staining were monitored as indicators of apoptosis. Intracellular calcium was detected by flow cytometry with Fluo-4 AM. The phosphorylation and activation of focal adhesion kinase (FAK) and signal transducer and activator of transcription 3 (STAT3) were measured by western blot. The expression levels of X-linked inhibitor of apoptosis protein (XIAP), B-cell lymphoma 2 (Bcl-2), B-cell lymphoma-extra large (Bcl-xL), SOD1, and SOD2 were also assessed by western blot. Mitochondrial status was assessed with tetramethylrhodamine, ethyl ester (TMRE), and intracellular adenosine triphosphate (ATP) was measured with BioTracker ATP-Red Live Cell Dye. Total cellular integrin levels were evaluated by western blot, and the expression of cell surface integrins was assessed using fluorescent-labelled antibodies and flow cytometry.

Results

Benzamil suppressed growth of osteosarcoma cells by inducing apoptosis. Benzamil reduced the expression of cell surface integrins α5, αV, and β1 in MG63 cells, while it only reduced the expression of αV in U2OS cells. Benzamil suppressed the phosphorylation and activation of FAK and STAT3. In addition, mitochondrial function and ATP production were compromised by benzamil. The levels of anti-apoptotic proteins XIAP, Bcl-2, and Bcl-xL were reduced by benzamil. Correspondingly, benzamil potentiated cisplatin- and methotrexate-induced apoptosis in osteosarcoma cells.

Conclusion

Benzamil exerts anti-osteosarcoma activity by inducing apoptosis. In terms of mechanism, benzamil appears to inhibit integrin/FAK/STAT3 signalling, which triggers mitochondrial dysfunction and ATP depletion.

Characterization of caspase gene family in Sebastes schlegelii and their expression profiles under Aeromonas salmonicida and Vibrio anguillarum infection

The caspase, functioning as a proteinase, plays a crucial role in eukaryotic cell apoptosis, regulation of apoptosis, cellular growth, differentiation, and immunity. The identification of caspase gene family in Sebastes schlegelii is of great help to understand its antimicrobial research. In S. schlegelii, we totally identified nine caspase genes, including four apoptosis initiator caspases (caspase 2, caspase 8, caspase 9 and caspase 10), four apoptosis executioners (caspase 3a, caspase 3b, caspase 6, and caspase 7) and one inflammatory executioner (caspase 1). The duplication of caspase 3 genes on chr3 and chr8 may have been facilitated by whole genome duplication (WGD) events or other complex evolutionary processes. In general, the number of caspase genes relatively conserved in high vertebrates, while exhibiting variation in teleosts. Furthermore, syntenic analysis and phylogenetic relationships analysis supported the correct classification of these caspase gene family in S. schlegelii, especially for genes with duplicated copies. Additionally, the expression patterns of these caspase genes in different tissues of S. schlegelii under healthy conditions were assessed. The results revealed that the expression levels of most caspase genes were significantly elevated in the intestine, spleen, and liver. To further investigate the potential immune functions of these caspase genes in S. schlegelii, we challenged individuals with A. salmonicida and V. anguillarum, respectively. After infection with A. salmonicida, the expression levels of caspase 1 in the liver and spleen of S. schlegelii remained consistently elevated throughout the infection time points. The expression levels of most caspase family members in the intestine exhibited significant divergence following V. anguillarum infection. This study provides a comprehensive understanding of the caspase gene families in S. schlegelii, thereby establishing a solid foundation for further investigations into the functional roles of these caspase genes.

Xanthorrhizol derivatives and their biological properties as caspase-7 inhibitors

Xanthorrhizol (1) is known as the major terpenoid component of the rhizome of Curcuma xanthorrhiza and having some interesting biological activities. In this report, we synthesised five derivatives of 1 containing nitrogen-functional groups. Four of them are new synthesised compounds, including (R)-4-(3-(2-methyl-5-(6-methylhept-5-en-2-yl)phenoxy)propyl)morpholine (2), (R)-N-benzyl-3-(2-methyl-5-(6-methylhept-5-en-2-yl)phenoxy)propan-1-amine (3), (R)-6,7-dimethoxy-3-(3-(2-methyl-5-(6-methylhept-5-en-2-yl)phenoxy)propyl)quinazolin-4(3H)-one (4), and (R)-6-methyl-3-(6-methylhept-5-en-2-yl)-2-nitrophenol (5) groups. Meanwhile the other is the known compound, that is (R)-2-methyl-5-(6-methylhept-5-en-2-yl)-4-nitrophenol (6). The caspase-7 inhibitory activity of compounds 1-6 was evaluated as well. In comparison to other derivatives, compounds 5 and 6 exhibited higher activity. Consequently, compounds 5 and 6 may be a promising lead compound for further development as a caspase-7 inhibitor.

The effect of polystyrene nanoplastics on arsenic-induced apoptosis in HepG2 cells

Microplastics are detrimental to the environment. However, the combined effects of microplastics and arsenic (As) remain unclear. In this study, we investigated the combined effects of polystyrene (PS) microplastics and As on HepG2 cells. The results showed that PS microplastics 20, 50, 200, and 500 nm in size were taken up by HepG2 cells, causing a decrease in cellular mitochondrial membrane potential. The results of lactate dehydrogenase release and flow cytometry showed that PS microplastics, especially those of 50 nm, enhanced As-induced apoptosis. In addition, transcriptome analysis revealed that TP53, AKT1, CASP3, ACTB, BCL2L1, CASP8, XIAP, MCL1, NFKBIA, and CASP7 were the top 10 hub genes for PS that enhanced the role of As in HepG2 cell apoptosis. Our results suggest that nano-PS enhances As-induced apoptosis. Furthermore, this study is important for a better understanding of the role of microplastics in As-induced hepatotoxicity.

Lidocaine induces apoptosis in head and neck squamous cell carcinoma through activation of bitter taste receptor T2R14

Head and neck squamous cell carcinomas (HNSCCs) have high mortality and significant treatment-related morbidity. It is vital to discover effective, minimally invasive therapies that improve survival and quality of life. Bitter taste receptors (T2Rs) are expressed in HNSCCs, and T2R activation can induce apoptosis. Lidocaine is a local anesthetic that also activates bitter taste receptor 14 (T2R14). Lidocaine has some anti-cancer effects, but the mechanisms are unclear. Here, we find that lidocaine causes intracellular Ca2+ mobilization through activation of T2R14 in HNSCC cells. T2R14 activation with lidocaine depolarizes mitochondria, inhibits proliferation, and induces apoptosis. Concomitant with mitochondrial Ca2+ influx, ROS production causes T2R14-dependent accumulation of poly-ubiquitinated proteins, suggesting that proteasome inhibition contributes to T2R14-induced apoptosis. Lidocaine may have therapeutic potential in HNSCCs as a topical gel or intratumor injection. In addition, we find that HPV-associated (HPV+) HNSCCs are associated with increased TAS2R14 expression. Lidocaine treatment may benefit these patients, warranting future clinical studies.

Gene expression profile of HCT-8 cells following single or co-infections with Cryptosporidium parvum and bovine coronavirus

Among the causative agents of neonatal diarrhoea in calves, two of the most prevalent are bovine coronavirus (BCoV) and the intracellular parasite Cryptosporidium parvum. Although several studies indicate that co-infections are associated with greater symptom severity, the host-pathogen interplay remains unresolved. Here, our main objective was to investigate the modulation of the transcriptome of HCT-8 cells during single and co-infections with BCoV and C. parvum. For this, HCT-8 cells were inoculated with (1) BCoV alone, (2) C. parvum alone, (3) BCoV and C. parvum simultaneously. After 24 and 72 h, cells were harvested and analyzed using high-throughput RNA sequencing. Following differential expression analysis, over 6000 differentially expressed genes (DEGs) were identified in virus-infected and co-exposed cells at 72 hpi, whereas only 52 DEGs were found in C. parvum-infected cells at the same time point. Pathway (KEGG) and gene ontology (GO) analysis showed that DEGs in the virus-infected and co-exposed cells were mostly associated with immune pathways (such as NF-κB, TNF-α or, IL-17), apoptosis and regulation of transcription, with a more limited effect exerted by C. parvum. Although the modulation observed in the co-infection was apparently dominated by the virus, over 800 DEGs were uniquely expressed in co-exposed cells at 72 hpi. Our findings provide insights on possible biomarkers associated with co-infection, which could be further explored using in vivo models.

de novo transcriptome assembly for discovering gene expressed in Holothuria leucospilota with exposed to copper

Sea cucumber is a bioremediator as it can composite organic matter and excrete inorganic matter. Sea cucumber has the potential to serve as a bioindicator in marine habitat as they provide an integrated insight into the status of their environment over long periods. Sea cucumbers are sensitive to the organic concentration in the marine environment and can effectively provide an early warning system for any organic contamination that can negatively impact the ecosystem. The availability of a reference transcriptome for sea cucumber would constitute an essential tool for identifying genes involved in crucial steps of the defence pathway. De novo assembly of RNA-seq data enables researchers to study the transcriptomes without needing a genome sequence. In this study, sea cucumbers fed with Kappaphycus alvarezii powder were treated with 0.20 mg/L copper concentration comprehensive transcriptome data containing 75,149 Unigenes, with a total length of 20,460,032 bp. A total of 8820 genes were predicted from the unigenes, annotated, and functionally categorized into 25 functional groups with approximately 20% cluster in signal transduction mechanism. The reference transcriptome presented and validated in this study is meaningful for identifying a wide range of gene(s) related to the bioindication of sea cucumber in a high copper environment.

Xanthatin suppresses pancreatic cancer cell growth via the ROS/RBL1 signaling pathway: In vitro and in vivo insights

BACKGROUND

As a malignant digestive system tumor, pancreatic cancer has a high mortality rate. Xanthatin is a sesquiterpene lactone monomer compound purified from the traditional Chinese herb Xanthium strumarium L. It has been reported that Xanthatin exhibits inhibitory effects on various cancer cells in retinoblastoma, glioma, hepatoma, colon cancer, lung cancer, as well as breast cancer. However, in pancreatic cancer cells, only one report exists on the suppression of Prostaglandin E2 synthesis and the induction of caspase 3/7 activation in Xanthatin-treated MIA PaCa-2 cells, while systematic in vitro and in vivo investigations and related mechanisms have yet to be explored.

PURPOSE

This research aims to explore the in vitro and in vivo effects of Xanthatin on pancreatic cancer and its molecular mechanisms.

METHODS

The anticancer effects and mechanisms of Xanthatin on pancreatic cancer cells were assessed through employing cell counting kit-8 (CCK-8) assay, lactate dehydrogenase (LDH) assay, carboxyfluorescein diacetate succinimidyl ester (CFDA SE) cell proliferation assay, colony formation assay, wound healing assay, transwell assay, Annexin V-FITC/propidium iodide (PI) dual staining, Hoechst nuclear staining, Western blot analysis, phosphoproteomics, and reactive oxygen species (ROS) measurement. The in vivo anticancer effects of Xanthatin on pancreatic cancer cells were studied using a nude mouse model.

RESULTS

The present study showed that Xanthatin can prevent the proliferation and metastasis of pancreatic cancer cells and trigger the exposure of phosphatidylserine (PS), chromatin condensation, and caspase activation, thereby inducing apoptosis. Phosphoproteomic analysis indicated that Xanthatin inhibits the phosphorylation of the proliferation-associated protein RBL1, and oxidative stress can lead to RBL1 dephosphorylation. Further investigation revealed that Xanthatin significantly upregulates ROS levels in pancreatic cancer cells, and the antioxidant N-acetylcysteine (NAC) can reverse Xanthatin-induced cell proliferation inhibition and apoptosis. In addition, Xanthatin can suppress pancreatic cancer cell growth in a xenograft nude mouse model with low toxicity to the mice.

CONCLUSION

Xanthatin may inhibit the proliferation of pancreatic cancer cells and trigger apoptosis through the ROS/RBL1 signaling pathway.

Pathological Impact of Tau Proteolytical Process on Neuronal and Mitochondrial Function: a Crucial Role in Alzheimer's Disease

Tau protein plays a pivotal role in the central nervous system (CNS), participating in microtubule stability, axonal transport, and synaptic communication. Research interest has focused on studying the role of post-translational tau modifications in mitochondrial failure, oxidative damage, and synaptic impairment in Alzheimer's disease (AD). Soluble tau forms produced by its pathological cleaved induced by caspases could lead to neuronal injury contributing to oxidative damage and cognitive decline in AD. For example, the presence of tau cleaved by caspase-3 has been suggested as a relevant factor in AD and is considered a previous event before neurofibrillary tangles (NFTs) formation.Interestingly, we and others have shown that caspase-cleaved tau in N- or C- terminal sites induce mitochondrial bioenergetics defects, axonal transport impairment, neuronal injury, and cognitive decline in neuronal cells and murine models. All these abnormalities are considered relevant in the early neurodegenerative manifestations such as memory and cognitive failure reported in AD. Therefore, in this review, we will discuss for the first time the importance of truncated tau by caspases activation in the pathogenesis of AD and how its negative actions could impact neuronal function.

New Perspectives on the Role of Nuclear Proteases in Cell Death Pathways

Multiple factors can trigger cell death via various pathways, and nuclear proteases have emerged as essential regulators of these processes. While certain nuclear proteases have been extensively studied and their mechanisms of action are well understood, others remain poorly characterized. Regulation of nuclear protease activity is a promising therapeutic strategy that could selectively induce favorable cell death pathways in specific tissues or organs. Thus, by understanding the roles of newly discovered or predicted nuclear proteases in cell death processes, we can identify new pharmacological targets for improving therapeutic outcomes. In this article, we delved into the role of nuclear proteases in several types of cell death and explore potential avenues for future research and therapeutic development.

Repeated Rounds of Gonadotropin Stimulation Induce Imbalance in the Antioxidant Machinery and Activation of Pro-Survival Proteins in Mouse Oviducts

Controlled ovarian stimulation (COS) through gonadotropin administration has become a common procedure in assisted reproductive technologies. COS's drawback is the formation of an unbalanced hormonal and molecular environment that could alter several cellular mechanisms. On this basis, we detected the presence of mitochondrial DNA (mtDNA) fragmentation, antioxidant enzymes (catalase; superoxide dismutases 1 and 2, SOD-1 and -2; glutathione peroxidase 1, GPx1) and apoptotic (Bcl-2-associated X protein, Bax; cleaved caspases 3 and 7; phosphorylated (p)-heat shock protein 27, p-HSP27) and cell-cycle-related proteins (p-p38 mitogen-activated protein kinase, p-p38 MAPK; p-MAPK activated protein kinase 2, p-MAPKAPK2; p-stress-activated protein kinase/Jun amino-terminal kinase, p-SAPK/JNK; p-c-Jun) in the oviducts of unstimulated (Ctr) and repeatedly hyperstimulated (eight rounds, 8R) mice. While all the antioxidant enzymes were overexpressed after 8R of stimulation, mtDNA fragmentation decreased in the 8R group, denoting a present yet controlled imbalance in the antioxidant machinery. Apoptotic proteins were not overexpressed, except for a sharp increase in the inflammatory-related cleaved caspase 7, accompanied by a significant decrease in p-HSP27 content. On the other hand, the number of proteins involved in pro-survival mechanisms, such as p-p38 MAPK, p-SAPK/JNK and p-c-Jun, increased almost 50% in the 8R group. Altogether, the present results demonstrate that repeated stimulations cause the activation of the antioxidant machinery in mouse oviducts; however, this is not sufficient to induce apoptosis, and is efficiently counterbalanced by activation of pro-survival proteins.

lncfos/miR-212-5p/CASP7 Axis-Regulated miR-212-5p Protects the Brain Against Ischemic Damage

miR-212-5p has been reported to be involved in many biological processes. However, the role of miR-212-5p in ischemic stroke remains unclear. This study explored the biological role and potential mechanism of miR-212-5p in ischemic stroke by investigating the lncfos/miR-212-5p/CASP7 axis. A total of 32 patients with ischemic stroke and 32 age- and sex-matched healthy controls (HCs) were enrolled in this study. In addition, 336 rats were used in this study. The rats were subjected to middle cerebral artery occlusion (MCAO) and intracerebroventricular injection of a microRNA (miRNA) agomir, a miRNA antagomir, a short hairpin RNA (shRNA) lentiviral vector, or a negative control. The neurological deficit score was calculated; the infarct volume was measured; histopathological assays were performed; the neuronal apoptosis rate was determined; and the lncfos, miR-212-5p, and CASP7 expression levels in the peri-infarct area were assessed. In this study, we found that the expression level of miR-212-5p was significantly downregulated in the peri-infarct area and blood of the MCAO model rats and the blood of patients with ischemic stroke. A double-luciferase experiment showed that CASP7 was a direct target gene of miR-212-5p and that miR-212-5p was a target miRNA of lncfos. Lateral ventricular injection of the miR-212-5p agomir effectively inhibited the apoptosis induced by ischemic brain damage, reduced the infarct volume, attenuated the neurological deficit symptoms, and downregulated the expression of CASP7 in the peri-infarct area of the MCAO model rats. Suppressing lncfos with sh-fos led to the upregulated expression of miR-212-5p and played a neuroprotective role in the rat MCAO models. We concluded that miR-212-5p plays a neuroprotective role in ischemic stroke and that its function is regulated by the lncfos/miR-212-5p/CASP7 axis. Moreover, miR-212-5p may be a potential biomarker and therapeutic target for ischemic stroke.

Unveiling the Mechanistic Singularities of Caspases: A Computational Analysis of the Reaction Mechanism in Human Caspase-1

Caspases are cysteine proteases in charge of breaking a peptide bond next to an aspartate residue. Caspases constitute an important family of enzymes involved in cell death and inflammatory processes. A plethora of diseases, including neurological and metabolic diseases and cancer, are associated with the poor regulation of caspase-mediated cell death and inflammation. Human caspase-1 in particular carries out the transformation of the pro-inflammatory cytokine pro-interleukin-1β into its active form, a key process in the inflammatory response and then in many diseases, such as Alzheimer's disease. Despite its importance, the reaction mechanism of caspases has remained elusive. The standard mechanistic proposal valid for other cysteine proteases and that involves the formation of an ion pair in the catalytic dyad is not supported by experimental evidence. Using a combination of classical and hybrid DFT/MM simulations, we propose a reaction mechanism for the human caspase-1 that explains experimental observations, including mutagenesis, kinetic, and structural data. In our mechanistic proposal, the catalytic cysteine, Cys285, is activated after a proton transfer to the amide group of the scissile peptide bond, a process facilitated by hydrogen-bond interactions with Ser339 and His237. The catalytic histidine does not directly participate in any proton transfer during the reaction. After formation of the acylenzyme intermediate, the deacylation step takes place through the activation of a water molecule by the terminal amino group of the peptide fragment formed during the acylation step. The overall activation free energy obtained from our DFT/MM simulations is in excellent agreement with the value derived from the experimental rate constant, 18.7 vs 17.9 kcal·mol^-1, respectively. Simulations of the H237A mutant support our conclusions and agree with the reported reduced activity observed for this caspase-1 variant. We propose that this mechanism can explain the reactivity of all cysteine proteases belonging to the CD clan and that differences with respect to other clans could be related to the larger preference showed by enzymes of the CD clan for charged residues at position P1. This mechanism would avoid the free energy penalty associated with the formation of an ion pair. Finally, our structural description of the reaction process can be useful to assist in the design of inhibitors of caspase-1, a target in the treatment of several human diseases.

N6-Methyladenosine RNA Modifications Regulate the Response to Platinum Through Nicotinamide N-methyltransferase

Development of resistance to platinum (Pt) in ovarian cancer remains a major clinical challenge. Here we focused on identifying epitranscriptomic modifications linked to Pt resistance. Fat mass and obesity-associated protein (FTO) is a N6-methyladenosine (m6A) RNA demethylase that we recently described as a tumor suppressor in ovarian cancer. We hypothesized that FTO-induced removal of m6A marks regulates the cellular response of ovarian cancer cells to Pt and is linked to the development of resistance. To study the involvement of FTO in the cellular response to Pt, we used ovarian cancer cells in which FTO was knocked down via short hairpin RNA or overexpressed and Pt-resistant (Pt-R) models derived through repeated cycles of exposure to Pt. We found that FTO was significantly downregulated in Pt-R versus sensitive ovarian cancer cells. Forced expression of FTO, but not of mutant FTO, increased sensitivity to Pt in vitro and in vivo (P < 0.05). Increased numbers of γ-H2AX foci, measuring DNA double-strand breaks, and increased apoptosis were observed after exposure to Pt in FTO-overexpressing versus control cells. Through integrated RNA sequencing and MeRIP sequencing, we identified and validated the enzyme nicotinamide N-methyltransferase (NNMT), as a new FTO target linked to Pt response. NNMT was upregulated and demethylated in FTO-overexpressing cells. Treatment with an NNMT inhibitor or NNMT knockdown restored sensitivity to Pt in FTO-overexpressing cells. Our results support a new function for FTO-dependent m6A RNA modifications in regulating the response to Pt through NNMT, a newly identified RNA methylated gene target.

The double-edged functions of necroptosis

Necroptosis refers to a regulated form of cell death induced by a variety of stimuli. Although it has been implicated in the pathogenesis of many diseases, there is evidence to support that necroptosis is not purely a detrimental process. We propose that necroptosis is a "double-edged sword" in terms of physiology and pathology. On the one hand, necroptosis can trigger an uncontrolled inflammatory cascade response, resulting in severe tissue injury, disease chronicity, and even tumor progression. On the other hand, necroptosis functions as a host defense mechanism, exerting antipathogenic and antitumor effects through its powerful pro-inflammatory properties. Moreover, necroptosis plays an important role during both development and regeneration. Misestimation of the multifaceted features of necroptosis may influence the development of therapeutic approaches targeting necroptosis. In this review, we summarize current knowledge of the pathways involved in necroptosis as well as five important steps that determine its occurrence. The dual role of necroptosis in a variety of physiological and pathological conditions is also highlighted. Future studies and the development of therapeutic strategies targeting necroptosis should fully consider the complicated properties of this type of regulated cell death.

LDHA deficiency inhibits trophoblast proliferation via the PI3K/AKT/FOXO1/CyclinD1 signaling pathway in unexplained recurrent spontaneous abortion

Dysregulated trophoblast proliferation, invasion, and apoptosis may cause several pregnancy-associated complications, such as unexplained recurrent spontaneous abortion (URSA). Recent studies have shown that metabolic abnormalities, including glycolysis inhibition, may dysregulate trophoblast function, leading to URSA. However, the underlying mechanisms remain unclear. Herein, we found that lactate dehydrogenase A (LDHA), a key enzyme in glycolysis, was significantly reduced in the placental villus of URSA patients. The human trophoblast cell line HTR-8/SVneo was used to investigate the possible LDHA-mediated regulation of trophoblast function. LDHA knockdown in HTR-8/SVneo cells induced G0/G1 phase arrest and increased apoptosis, whereas LDHA overexpression reversed these effects. Next, RNA sequencing combined with Kyoto Encyclopedia of Genes and Genomes analysis demonstrated that the PI3K/AKT signaling pathway is potentially affected by downstream genes of LDHA. Especially, we found that LDHA knockdown decreased the phosphorylation levels of PI3K, AKT, and FOXO1, resulting in a significant downregulation of CyclinD1. In addition, treatment with an AKT inhibitor or FOXO1 inhibitor also verified that the PI3K/AKT/FOXO1 signaling pathway influenced the gene expression of CyclinD1 in trophoblast. Moreover, p-AKT expression correlated positively with LDHA expression in syncytiotrophoblasts and extravillous trophoblasts in first-trimester villus. Collectively, this study revealed a new regulatory pathway for LDHA/PI3K/AKT/FOXO1/CyclinD1 in the trophoblast cell cycle and proliferation.

Making the head: Caspases in life and death

The term apoptosis, as a way of programmed cell death, was coined a half century ago and since its discovery the process has been extensively investigated. The anatomy and physiology of the head are complex and thus apoptosis has mostly been followed in separate structures, tissues or cell types. This review aims to provide a comprehensive overview of recent knowledge concerning apoptosis-related molecules involved in the development of structures of head with a particular focus on caspases, cysteine proteases having a key position in apoptotic pathways. Since many classical apoptosis-related molecules, including caspases, are emerging in several non-apoptotic processes, these were also considered. The largest organ of the head region is the brain and its development has been extensively investigated, including the roles of apoptosis and related molecules. Neurogenesis research also includes sensory organs such as the eye and ear, efferent nervous system and associated muscles and glands. Caspases have been also associated with normal function of the skin and hair follicles. Regarding mineralised tissues within craniofacial morphogenesis, apoptosis in bones has been of interest along with palate fusion and tooth development. Finally, the role of apoptosis and caspases in angiogenesis, necessary for any tissue/organ development and maintenance/homeostasis, are discussed. Additionally, this review points to abnormalities of development resulting from improper expression/activation of apoptosis-related molecules.

The E3 Ligase TRIM25 Impairs Apoptotic Cell Death in Colon Carcinoma Cells via Destabilization of Caspase-7 mRNA: A Possible Role of hnRNPH1

Therapy resistance is still a major reason for treatment failure in colorectal cancer (CRC). Previously, we identified the E3 ubiquitin ligase TRIM25 as a novel suppressor of caspase-2 translation which contributes to the apoptosis resistance of CRC cells towards chemotherapeutic drugs. Here, we report the executioner caspase-7 as being a further target of TRIM25. The results from the gain- and loss-of-function approaches and the actinomycin D experiments indicate that TRIM25 attenuates caspase-7 expression mainly through a decrease in mRNA stability. The data from the RNA pulldown assays with immunoprecipitated TRIM25 truncations indicate a direct TRIM25 binding to caspase-7 mRNA, which is mediated by the PRY/SPRY domain, which is also known to be highly relevant for protein-protein interactions. By employing TRIM25 immunoprecipitation, we identified the heterogeneous nuclear ribonucleoprotein H1 (hnRNPH1) as a novel TRIM25 binding protein with a functional impact on caspase-7 mRNA stability. Notably, the interaction of both proteins was highly sensitive to RNase A treatment and again depended on the PRY/SPRY domain, thus indicating an indirect interaction of both proteins which is achieved through a common RNA binding. Ubiquitin affinity chromatography showed that both proteins are targets of ubiquitin modification. Functionally, the ectopic expression of caspase-7 in CRC cells caused an increase in poly ADP-ribose polymerase (PARP) cleavage concomitant with a significant increase in apoptosis. Collectively, the negative regulation of caspase-7 by TRIM25, which is possibly executed by hnRNPH1, implies a novel survival mechanism underlying the chemotherapeutic drug resistance of CRC cells. The targeting of TRIM25 could therefore offer a promising strategy for the reduction in therapy resistance in CRC patients.

Inhibition of Caspase 3 and Caspase 9 Mediated Apoptosis: A Multimodal Therapeutic Target in Traumatic Brain Injury

Traumatic brain injury (TBI) is one of the significant causes of death and morbidity, and it is hence a focus of translational research. Apoptosis plays an essential part in the pathophysiology of TBI, and its inhibition may help overcome TBI's negative consequences and improve functional recovery. Although physiological neuronal death is necessary for appropriate embryologic development and adult cell turnover, it can also drive neurodegeneration. Caspases are principal mediators of cell death due to apoptosis and are critical for the required cleavage of intracellular proteins of cells committed to die. Caspase-3 is the major executioner Caspase of apoptosis and is regulated by a range of cellular components during physiological and pathological conditions. Activation of Caspase-3 causes proteolyzation of DNA repair proteins, cytoskeletal proteins, and the inhibitor of Caspase-activated DNase (ICAD) during programmed cell death, resulting in morphological alterations and DNA damage that define apoptosis. Caspase-9 is an additional crucial part of the intrinsic pathway, activated in response to several stimuli. Caspases can be altered post-translationally or by modulatory elements interacting with the zymogenic or active form of a Caspase, preventing their activation. The necessity of Caspase-9 and -3 in diverse apoptotic situations suggests that mammalian cells have at least four distinct apoptotic pathways. Continued investigation of these processes is anticipated to disclose new Caspase regulatory mechanisms with consequences far beyond apoptotic cell death control. The present review discusses various Caspase-dependent apoptotic pathways and the treatment strategies to inhibit the Caspases potentially.

Caspase-8 but not caspase-7 influences inflammasome activation to act in control of Brucella abortus infection

Programmed cell death (PCD) is an important mechanism of innate immunity against bacterial pathogens. The innate immune PCD pathway involves the molecules caspase-7 and caspase-8, among others. Brucella abortus is a gram-negative bacterium that causes a zoonotic disease termed brucellosis. The innate immune response against this pathogen involves activation of inflammasome components and induction of pyroptosis. However, no studies so far have revealed the role of caspase-7 or caspase-8 during this bacterial infection. Herein, we demonstrate that caspase-7 is dispensable for caspase-1 processing, IL-1β secretion and cell death in macrophages. Additionally, caspase-7 deficient animals control B. abortus infection as well as the wild type mice. Furthermore, we addressed the role of caspase-8 in inflammasome activation and pyroptosis during this bacterial infection. Macrophages deficient in caspase-8 secreted reduced amounts of IL-1β that parallels with diminished caspase-1 activity when compared to wild type cells. Additionally, caspase-8 KO macrophages showed reduced LDH release when compared to wild type, suggesting that caspase-8 may play an important role in pyroptosis in response to B. abortus. Finally, caspase-8 KO animals were more susceptible to Brucella infection when compared to wild type mice. Overall, this study contributes to a better understanding of the involvement of caspase-7 and caspase-8 in innate immunity against B. abortus infection.

Identifying tumor immunity-associated molecular features in liver hepatocellular carcinoma by multi-omics analysis

Background: Although current immunotherapies have achieved some successes for hepatocellular carcinoma (HCC) patients, their benefits are limited for most HCC patients. Therefore, the identification of biomarkers for promoting immunotherapeutic responses in HCC is urgently needed.

Methods: Using the TCGA HCC cohort, we investigated correlations of various molecular features with antitumor immune signatures (CD8⁺ T cell infiltration and cytolytic activity) and an immunosuppressive signature (PD-L1 expression) in HCC. These molecular features included mRNAs, microRNAs (miRNAs), long non-coding RNAs (lncRNAs), proteins, and pathways.

Results: We found that the mutations of several oncogenes and tumor suppressor genes significantly correlated with reduced antitumor immune signatures, including TTN, CTNNB1, RB1, ZFHX4, and TP53. It indicates that these genes’ mutations may inhibit antitumor immune responses in HCC. Four proteins (Syk, Lck, STAT5, and Caspase-7) had significant positive expression correlations with CD8⁺ T cell enrichment, cytolytic activity, and PD-L1 expression in HCC. It suggests that these proteins’ expression could be useful biomarkers for the response to immune checkpoint inhibitors Similiarly, we identified other types of biomarkers potentially useful for predicting the response to ICIs, including miRNAs (hsa-miR-511-5p, 150-3p, 342-3p, 181a-3p, 625-5p, 4772-3p, 155-3p, 142-5p, 142-3p, 155-5p, 625-3p, 1976, 7702), many lncRNAs, and pathways (apoptosis, cytokine-cytokine receptor interaction, Jak-STAT signaling, MAPK signaling, PI3K-AKT signaling, HIF-1 signaling, ECM receptor interaction, focal adhesion, and estrogen signaling). Further, tumor mutation burden showed no significant correlation with antitumor immunity, while tumor aneuploidy levels showed a significant negative correlation with antitumor immunity.

Conclusion: The molecular features significantly associated with HCC immunity could be predictive biomarkers for immunotherapeutic responses in HCC patients. They could also be potential intervention targets for boosting antitumor immunity and immunotherapeutic responses in HCC.

Ovarian tumor deubiquitinase 6A regulates cell proliferation via deubiquitination of nucleolin and caspase‑7

Most proteins maintain protein homeostasis via post‑translational modifications, including the ubiquitin‑proteasome system. Deubiquitinating enzymes (DUBs) have essential intercellular roles, such as responses to DNA damage, proteolysis and apoptosis. Therefore, it is important to understand DUB‑related diseases to identify DUBs that target abnormally regulated proteins in cells. Ovarian tumor deubiquitinase 6A (OTUD6A) was previously reported as a downregulated DUB in HCT116 cells with p53 knockdown. Therefore, it was expected that the relationship between OTUD6A and p53 would affect cell proliferation. In the present study, putative substrates of OTUD6A related to the p53 signaling pathway were identified. Application of liquid chromatography‑tandem mass spectrometry and proteomic analysis led to the identification of nucleolin (known to bind p53) as a binding protein. In addition, immunoprecipitation studies determined that caspase‑7, an apoptotic protein, is associated with p53 signaling and is regulated by OTUD6A. It was further identified that OTUD6A regulates the protein stability of nucleolin, but not caspase‑7. It was also demonstrated that OTUD6A acts as a respective DUB through the deubiquitination of K48‑linked polyubiquitin chain of nucleolin and the K63‑linked polyubiquitin chain of caspase‑7. Furthermore, overexpression of OTUD6A induced cell proliferation via enhancing cell cycle progression of MCF7 cells. Taken together, OTUD6A may be proposed as a target for anticancer therapy.

Molecular classification of human papillomavirus-positive cervical cancers based on immune signature enrichment

Background

Human papillomavirus-positive (HPV+) cervical cancers are highly heterogeneous in clinical and molecular characteristics. Thus, an investigation into their heterogeneous immunological profiles is meaningful in providing both biological and clinical insights into this disease.

Methods

Based on the enrichment of 29 immune signatures, we discovered immune subtypes of HPV+ cervical cancers by hierarchical clustering. To explore whether this subtyping method is reproducible, we analyzed three bulk and one single cell transcriptomic datasets. We also compared clinical and molecular characteristics between the immune subtypes.

Results

Clustering analysis identified two immune subtypes of HPV+ cervical cancers: Immunity-H and Immunity-L, consistent in the four datasets. In comparisons with Immunity-L, Immunity-H displayed stronger immunity, more stromal contents, lower tumor purity, proliferation potential, intratumor heterogeneity and stemness, higher tumor mutation burden, more neoantigens, lower levels of copy number alterations, lower DNA repair activity, as well as better overall survival prognosis. Certain genes, such as MUC17, PCLO, and GOLGB1, showed significantly higher mutation rates in Immunity-L than in Immunity-H. 16 proteins were significantly upregulated in Immunity-H vs. Immunity-L, including Caspase-7, PREX1, Lck, C-Raf, PI3K-p85, Syk, 14-3-3_epsilon, STAT5-α, GATA3, Src_pY416, NDRG1_pT346, Notch1, PDK1_pS241, Bim, NF-kB-p65_pS536, and p53. Pathway analysis identified numerous immune-related pathways more highly enriched in Immunity-H vs. Immunity-L, including cytokine-cytokine receptor interaction, natural killer cell-mediated cytotoxicity, antigen processing and presentation, T/B cell receptor signaling, chemokine signaling, supporting the stronger antitumor immunity in Immunity-H vs. Immunity-L.

Conclusion

HPV+ cervical cancers are divided into two subgroups based on their immune signatures' enrichment. Both subgroups have markedly different tumor immunity, progression phenotypes, genomic features, and clinical outcomes. Our data offer novel perception in the tumor biology as well as clinical implications for HPV+ cervical cancer.

Design, synthesis, and biological evaluation of new celecoxib analogs as apoptosis inducers and cyclooxygenase-2 inhibitors

Series of new celecoxib analogs were synthesized to assess their anticancer activity against the MCF-7 cell line. Four compounds, 3a, 3c, 5b, and 5c, showed 1.4-9.2-fold more potent anticancer activity than celecoxib. The antiproliferative activity of the most potent compounds, 3c, 5b, and 5c, seems to be associated well with their ability to induce apoptosis in MCF-7 cells (18-24-fold). This evidence was supported by an increase in the expression of the tumor suppressor gene p53 (4-6-fold), the elevation in the Bax/BCL-2 ratio, and a significant increase in the level of active caspase-7 (4-7-fold). Moreover, compounds 3c and 5c showed significant cyclooxygenase-2 (COX-2) inhibitory activity. They were also docked into the crystal structure of the COX-2 enzyme (PDB ID: 3LN1) to understand their mode of binding.

Neuregulin-1 signaling regulates cytokines and chemokines expression and secretion in granulosa cell

BACKGROUND

Granulosa cells (GCs) are multilayered somatic cells within the follicle that provide physical support and microenvironment for the developing oocyte. In recent years, the role of Neuregulin-1 (NRG1), a member of the EGF-like factor family, has received considerable attention due to its neurodevelopmental and cardiac function. However, the exact physiological role of NRG1 in GC is mainly unknown. In order to confirm that NRG1 plays a regulatory role in rat GC functions, endogenous NRG1-knockdown studies were carried out in GCs using RNA interference methodology.

RESULTS

Knockdown of NRG1 in GCs resulted in the enhanced expression and secretion of the cytokines and chemokines. In addition, the phosphorylation of PI3K/Akt/ERK1/2 was significantly low in GCs under these experimental conditions. Moreover, in vitro experimental studies suggest that tumor necrosis factor-α (TNFα) treatment causes the physical destruction of GCs by activating caspase-3/7 activity. In contrast, exogenous NRG1 co-treatment of GCs delayed the onset of TNFα-induced apoptosis and inhibited the activation of caspase-3/7 activity. Furthermore, current experimental studies suggest that gonadotropins promote differential expression of NRG1 and ErbB3 receptors in GCs of the antral follicle. Interestingly, NRG1 and ErbB3 were intensely co-localized in the mural and cumulus GCs and cumulus-oocyte complex of pre-ovulatory follicles in the estrus stage.

CONCLUSIONS

The present studies suggest that gonadotropins-dependent NRG1-signaling in GCs may require the balance of the cytokines and chemokines expression and secretion, ultimately which may be supporting the follicular maturation and oocyte competence for ovulation and preventing follicular atresia.

Advances in the Therapeutic Effects of Apoptotic Bodies on Systemic Diseases

Apoptosis plays an important role in development and in the maintenance of homeostasis. Apoptotic bodies (ApoBDs) are specifically generated from apoptotic cells and can contain a large variety of biological molecules, which are of great significance in intercellular communications and the regulation of phagocytes. Emerging evidence in recent years has shown that ApoBDs are essential for maintaining homeostasis, including systemic bone density and immune regulation as well as tissue regeneration. Moreover, studies have revealed the therapeutic effects of ApoBDs on systemic diseases, including cancer, atherosclerosis, diabetes, hepatic fibrosis, and wound healing, which can be used to treat potential targets. This review summarizes current research on the generation, application, and reconstruction of ApoBDs regarding their functions in cellular regulation and on systemic diseases, providing strong evidence and therapeutic strategies for further insights into related diseases.

Ruellia tuberosa Ethyl Acetate Leaf Extract Induces Apoptosis and Cell Cycle Arrest in Human Breast Cancer Cell Line, MCF-7

Ruellia tuberosa L. has been previously shown to possess antioxidant and antiproliferative activities on cancer cells but its underlying mechanisms are largely unknown. This study aimed to elucidate the mode of action underlying this inhibitory effect on MCF-7 using ethyl acetate extract obtained after liquid-liquid partition of methanol crude extract. Antiproliferative effect of R. tuberosa ethyl acetate leaf extract (RTEAL) was evaluated using MTT assay. Its ability to induce apoptosis was assessed by DNA ladder formation, JC-1, Annexin V, and methylene blue staining assays. Perturbation of cell cycle progression was determined using flow cytometry. RTEAL was found to selectively inhibit the proliferation of MCF-7 cells with the IC50 value of 28 µg/mL. Morphological changes such as nuclear fragmentation and chromatin condensation were observed although DNA laddering was undetected in agarose gel. RTEAL-induced apoptotic pathways by inhibiting the expression of anti-apoptotic BCL-2 while upregulating pro-apoptotic BAX, caspase 7 and caspase 8. RTEAL also caused cell cycle arrests at the S and G2/M phase and dysregulation of cell cycle regulators. These findings collectively demonstrate that RTEAL extract inhibited cell growth by inducing apoptosis and cell cycle arrest, suggesting its therapeutic potential against breast cancer.

Apoptosis Induction Associated with Enhanced ER Stress Response and Up-Regulation of c-Jun/p38 MAPK Proteins in Human Cervical Cancer Cells by Colocasia esculenta var. aquatilis Hassk Extract

Colocasia esculenta var. Aquatilis Hassk, elephant ear (CF-EE) has been widely used as traditional food and medicine. It also shows other therapeutic properties, such as antimicrobial and anti-cancer activity. In this study, we aim to investigate the effect of CF-EE extract on apoptosis induction associated with ER stress in cervical cancer HeLa cells. Cell viability was determined by MTT assay. Assessments of nuclear morphological changes, mitochondrial membrane potential, and intracellular reactive oxygen species (ROS) production were conducted by hoeshst33342, JC-1, and DCFH-DA fluorescence staining, respectively. Sub-G1 DNA content was analyzed by flow cytometry, and protein expression was determined by Western blotting. The results demonstrate that CF-EE extract suppressed HeLa cell growth and induced nuclear condensation and apoptotic bodies. There was also a loss of mitochondrial membrane potential and increased apoptosis marker protein expression, including Bax, cleaved-caspase-7, and cleaved-PARP. In addition, the results show that CF-EE extract induced ROS, increased ER stress proteins (GRP78 and CHOP), enhanced p38 and c-Jun phosphorylation, and inhibited Akt expression in HeLa cells. In summary, CF-EE extract induced apoptotic cell death-associated ROS-induced ER stress and the MAPK/AKT signaling pathway. Therefore, CF-EE extract has anticancer therapeutic potential for cervical cancer treatment in the future.

Current Concepts of Vitiligo Immunopathogenesis

Vitiligo is an acquired immune-mediated disorder of pigmentation clinically characterized by well-defined depigmented or chalk-white macules and patches on the skin. The prevalence of vitiligo varies by geographical area, affecting 0.5% to 2% of the population. The disease imposes a significant psychological burden due to its major impact on patients’ social and emotional aspects of life. Given its autoimmune background, vitiligo is frequently associated with other autoimmune diseases or immune-mediated diseases. Vitiligo is a multifaceted disorder that involves both genetic predisposition and environmental triggers. In recent years, major predisposing genetic loci for the development of vitiligo have been discovered. The current findings emphasize the critical role of immune cells and their mediators in the immunopathogenesis of vitiligo. Oxidative-stress-mediated activation of innate immunity cells such as dendritic cells, natural killer, and ILC-1 cells is thought to be a key event in the early onset of vitiligo. Innate immunity cells serve as a bridge to adaptive immunity cells including T helper 1 cells, cytotoxic T cells and resident memory T cells. IFN-γ is the primary cytokine mediator that activates the JAK/STAT pathway, causing keratinocytes to produce the key chemokines CXCL9 and CXCL10. Complex interactions between immune and non-immune cells finally result in apoptosis of melanocytes. This paper summarizes current knowledge on the etiological and genetic factors that contribute to vitiligo, with a focus on immunopathogenesis and the key cellular and cytokine players in the disease’s inflammatory pathways.

Bacterial Quorum-Sensing Signal DSF Inhibits LPS-Induced Inflammations by Suppressing Toll-like Receptor Signaling and Preventing Lysosome-Mediated Apoptosis in Zebrafish

Bacteria and their eukaryotic hosts have co-evolved for millions of years, and the former can intercept eukaryotic signaling systems for the successful colonization of the host. The diffusible signal factor (DSF) family represents a type of quorum-sensing signals found in diverse Gram-negative bacterial pathogens. Recent evidence shows that the DSF is involved in interkingdom communications between the bacterial pathogen and the host plant. In this study, we explored the anti-inflammatory effect of the DSF and its underlying molecular mechanism in a zebrafish model. We found that the DSF treatment exhibited a strong protective effect on the inflammatory response of zebrafish induced by lipopolysaccharide (LPS). In the LPS-induced inflammation zebrafish model, the DSF could significantly ameliorate the intestinal pathological injury, reduce abnormal migration and the aggregation of inflammatory cells, inhibit the excessive production of inflammatory mediator reactive oxygen species (ROS) content, and prevent apoptosis. Through an RNA-Seq analysis, a total of 938 differentially expressed genes (DEGs) was screened between LPS and LPS + DSF treatment zebrafish embryos. A further bioinformatics analysis and validation revealed that the DSF might inhibit the LPS-induced zebrafish inflammatory response by preventing the activation of signaling in the Toll-like receptor pathway, attenuating the expression of pro-inflammatory cytokines and chemokines, and regulating the activation of the caspase cascade through restoring the expression of lysosomal cathepsins and apoptosis signaling. This study, for the first time, demonstrates the anti-inflammatory role and a potential pharmaceutical application of the bacterial signal DSF. These findings also suggest that the interkingdom communication between DSF-producing bacteria and zebrafish might occur in nature.

Effect of retinol and α-tocopherol supplementation on photoreceptor and retinal ganglion cell apoptosis in diabetic rats model

BACKGROUND

Diabetic retinopathy (DR) is the most common microvascular complication of diabetes. Retinol and α-tocopherol of diabetic models prevent the damage of photoreceptor and retinal ganglion cells (RGC) caused by hyperglycemia.

OBJECTIVE

This study aims to examine the effect of retinol and α-tocopherol on photoreceptor and RGC densities and the expression of caspase-3 and -7 on the retinal layers of the diabetic rat model.

METHODS

Alloxan 150 mg/kg body weight single dose was used to develop animal models, which were separated into eight groups. These consist of one group without intervention (group 1), one positive control with only induced alloxan (group 2), and others receiving retinol (group 3 and 6), α-tocopherol (group 4 and 7), or their combination (group 5 and 8). Furthermore, histopathological examination was performed using Hematoxylin-Eosin staining to evaluate the photoreceptor and RGC densities, while immunohistochemistry staining evaluated the caspase-3 and -7 expressions.

RESULTS

In the treatment group, the highest and lowest densities were identified in diabetic rats given α-tocopherol (group 7) and retinol (group 3) respectively. The caspase-3 and -7 expression showed that the group given α-tocopherol (group 7) had the lowest value.

CONCLUSION

In diabetic rats, retinol and α-tocopherol compounds maintained densities and prevented photoreceptor and RGC death. However, α-tocopherol was more promising than retinol or combinations in the prevention of retinal cells apoptosis.

EGR1 Upregulation during Encephalitic Viral Infections Contributes to Inflammation and Cell Death

Early growth response 1 (EGR1) is an immediate early gene and transcription factor previously found to be significantly upregulated in human astrocytoma cells infected with Venezuelan equine encephalitis virus (VEEV). The loss of EGR1 resulted in decreased cell death but had no significant impact on viral replication. Here, we extend these studies to determine the impacts of EGR1 on gene expression following viral infection. Inflammatory genes CXCL3, CXCL8, CXCL10, TNF, and PTGS2 were upregulated in VEEV-infected cells, which was partially dependent on EGR1. Additionally, transcription factors, including EGR1 itself, as well as ATF3, FOS, JUN, KLF4, EGR2, and EGR4 were found to be partially transcriptionally dependent on EGR1. We also examined the role of EGR1 and the changes in gene expression in response to infection with other alphaviruses, including eastern equine encephalitis virus (EEEV), Sindbis virus (SINV), and chikungunya virus (CHIKV), as well as Zika virus (ZIKV) and Rift Valley fever virus (RVFV), members of the Flaviviridae and Phenuiviridae families, respectively. EGR1 was significantly upregulated to varying degrees in EEEV-, CHIKV-, RVFV-, SINV-, and ZIKV-infected astrocytoma cells. Genes that were identified as being partially transcriptionally dependent on EGR1 in infected cells included ATF3 (EEEV, CHIKV, ZIKV), JUN (EEEV), KLF4 (SINV, ZIKV, RVFV), CXCL3 (EEEV, CHIKV, ZIKV), CXCL8 (EEEV, CHIKV, ZIKV, RVFV), CXCL10 (EEEV, RVFV), TNF-α (EEEV, ZIKV, RVFV), and PTGS2 (EEEV, CHIKV, ZIKV). Additionally, inhibition of the inflammatory gene PTGS2 with Celecoxib, a small molecule inhibitor, rescued astrocytoma cells from VEEV-induced cell death but had no impact on viral titers. Collectively, these results suggest that EGR1 induction following viral infection stimulates multiple inflammatory mediators. Managing inflammation and cell death in response to viral infection is of utmost importance, especially during VEEV infection where survivors are at-risk for neurological sequalae.

Enzalutamide Overcomes Dihydrotestosterone Induced Chemo-Resistance In Triple-Negative Breast Cancer Cells via Apoptosis

Background:

Triple-negative breast cancer is challenging to treat due to its heterogeneity and lack of therapeutic targets. Hence, systemic chemotherapy is still the mainstay in TNBC treatment. Unfortunately, patients commonly develop chemo-resistance. Androgen signalling through its receptor is an essential player in breast cancer where it has been shown to confer chemo-resistance to TNBC cells

Objective:

To elucidate the mechanistic effects of enzalutamide in the chemoresponse of TNBC cells to doxorubicin through the apoptosis pathway.

Results:

Enzalutamide decreased the viability of MDA-MB-231 and MDA-MB- 453 cells and reduced DHT-induced chemo-resistance of both cell lines. It also increased the chemo-sensitivity towards doxorubicin in MDA-MB-231 cells. Increasing DNA degradation and caspase 3/7 activity were concomitant with these outcomes. Moreover, enzalutamide downregulated the expression of the anti-apoptosis genes, mcl1 and bcl2, in MDA-MB-231 cells. Moreover, increase the pro-apoptotic gene bid. On the other hand, DHT upregulated the expression of the anti-apoptosis genes, mcl1 and bcl2, in both cell lines.

Conclusion:

DHT increases the expression of the anti-apoptosis mcl1 and bcl2 in the TNBC cells, presumably leading to cell survival via the prevention of doxorubicin-induced apoptosis. On the other hand, enzalutamide may sensitize the cells to doxorubicin through downregulation of the bid/bcl2/mcl1 axis that normally activates the executive caspases, caspase 3/7. The activities of the latter enzymes were apparent in DNA degradation at the late stages of

Hypoxia-inducible factor (HIF)-3a2 serves as an endothelial cell fate executor during chronic hypoxia

The adaptive response to hypoxia involves the transcriptional induction of three transcription factors called hypoxia inducible factor alpha 1, 2 and 3 (HIF-1α, HIF-2α, and HIF-3α) which dimerize with constitutively expressed beta chains that together form the HIF-1, -2 and -3 transcription factors. During normoxic conditions, the alpha chain is expressed at low levels since its stability is regulated by prolyl-hydroxylation that promotes subsequent ubiquitination and degradation. During hypoxic conditions, however, the prolyl hydroxylases are less active, and the alpha chain accumulates through elevated protein stability and the elevated induction of expression. Two of the three HIFs isoforms present in mammals, HIF-1 and HIF-2, are well characterized and have overlapping functions that promote cell survival, whereas HIF-3's role remains less clear. The HIF-3 response is complicated because the HIF3A gene can utilize different promotors and alternate splicing sites that result in a number of different HIF-3α isoforms. Here, using human umbilical vein endothelial cells (HUVECs), we demonstrate that one of the isoforms of HIF-3α, isoform 2 (HIF-3α2) accumulates at a late stage of hypoxia and induces the expression of DNA damage inducible transcript 3 (DDIT4), a gene known to promote apoptosis. We also demonstrate that caspase 3/7 activity is elevated, supporting that the role of the HIF-3α2 isoform is to promote apoptosis. Furthermore, we provide evidence that HIF-3α2 is also expressed in seven other primary endothelial cell types, suggesting that this may be a common feature of HIF-3α2 in endothelial cells.

Design and Synthesis of Novel Celecoxib Analogues with Potential Cytotoxic and Pro-apoptotic Activity Against Breast Cancer Cell Line MCF-7

BACKGROUND

Breast cancer is currently the leading cause of worldwide cancer incidence exceeding lung cancer. In addition, breast cancer accounts for 1 in 4 cancer cases and 1 in 6 cancer deaths among women. Cytotoxic chemotherapy is still the main therapeutic approach for patients with metastatic breast cancer.

OBJECTIVE

To synthesize a series of novel celecoxib analogues to evaluate their anticancer activity against MCF-7 cell line.

METHOD

Our design of target compounds was based on preserving the pyrazole moiety of celecoxib attached to two phenyl rings, one of them having polar hydrogen bonding group (sulfonamide or methoxy group). The methyl group of the second phenyl ring was replaced with chlorine or bromine atom. Finally, the trifluoromethyl group was replaced with arylidene hydrazine-1-carbonyl moiety, which is substituted either with fluoro or methoxy group, offering various electronic and lipophilic environments. These modifications were carried out to investigate their effects on the anti-proliferative activity of the newly synthesized celecoxib analogues and to provide a valuable structure activity relationship.

RESULTS

Four compounds namely (4e-h) exhibited significant antitumor activity. Compounds 4e, 4f and 4h showed 1.2-2 folds more potent anticancer activity than celecoxib. Celecoxib analogue 4f showed the most potent anti-proliferative activity. Its anti-proliferative activity seems to associate well with its ability to inhibit BCL-2. Moreover, activation of damage response pathway of the DNA leads to cell cycle arrest at G2/M phase, accumulation of cells in pre-G1 phase, indicating that cell death proceeds through an apoptotic mechanism. Compound 4f exhibited potent pro-apoptotic effect via induction of the intrinsic mitochondrial pathway of apoptosis. This mechanistic pathway was proved by a significant increase in the expression of the tumor suppressor gene p53, elevation in Bax/BCL-2 ratio and a significant increase in the level of active caspase-7. Furthermore, compound 4f showed moderate COX-2 inhibitory activity.

CONCLUSION

Celecoxib analogue 4f is a promising multi-targeted lead for the design and synthesis of potent anticancer agents.

Krill oil supplementation reduces the growth of CT-26 orthotopic tumours in Balb/c mice

Background

We have previously reported that the free fatty acid extract (FFAE) of krill oil (KO) significantly inhibits the proliferation and migration, and induces apoptosis of colorectal cancer (CRC) cells. This study aimed to investigate the in vivo efficacy of various doses of KO supplementation on the inhibition of CRC tumour growth, molecular markers of proliferation, angiogenesis, apoptosis, the epidermal growth factor receptor (EGFR) and its downstream molecular signalling.

Methods

Male Balb/c mice were randomly divided into four groups with five in each group. The control (untreated) group received standard chow diet; and other three groups received KO supplementation at 5%, 10%, and 15% of their daily dietary intake respectively for three weeks before and after the orthotopic implantation of CT-26 CRC cells in their caecum. The expression of cell proliferation marker Ki-67 and angiogenesis marker CD-31 were assessed by immunohistochemistry. The expression of EGFR, phosphorylated EGFR (pEGFR), protein kinase B (AKT), pAKT, extracellular signal-regulated kinase (ERK1/2), pERK1/2, cleaved caspase-7, cleaved poly (ADP-ribose) polymerase (PARP), and DNA/RNA damage were determined by western blot.

Results

KO supplementation reduced the CRC tumour growth in a dose-dependent manner; with 15% of KO being the most effective in reduction of tumour weight and volume (68.5% and 68.3% respectively, P < 0.001), inhibition of cell proliferation by 69.9% (P < 0.001) and microvessel density by 72.7% (P < 0.001). The suppressive effects of KO on EGFR and its downstream signalling, ERK1/2 and AKT, were consistent with our previous in vitro observations. Furthermore, KO exhibited pro-apoptotic effects on tumour cells as indicated by an increase in the expression of cleaved PARP by 3.9-fold and caspase-7 by 8.9-fold.

Conclusions

This study has demonstrated that KO supplementation reduces CRC tumour growth by inhibiting cancer cell proliferation and blood vessel formation and inducing apoptosis of tumour cells. These anti-cancer effects are associated with the downregulation of the EGFR signalling pathway and activation of caspase-7, PARP cleavage, and DNA/RNA damage.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-022-03521-4.

The Antiproliferative and Apoptotic Effects of a Novel Quinazoline Carrying Substituted-Sulfonamides: In Vitro and Molecular Docking Study

In order to investigate for a new effective and safe anticancer drug, we synthesized a novel series of quinazoline containing biologically active substituted-sulfonamide moiety at 3- position 4a-n. The structure of the newly prepared compounds was proved by microanalysis, IR, ¹H-NMR, ¹³C-NMR and mass spectral data. All the synthesized compounds were evaluated for their in vitro cytotoxic activity in numerous cancer cell lines including A549, HepG-2, LoVo and MCF-7 and normal HUVEC cell line. The two most active compounds 4d and 4f were then tested for their apoptosis induction using DNA content and Annexin V-FITC/PI staining. Moreover, apoptosis initiation was also confirmed using RT-PCR and Western blot. To further understand the binding preferences of quinazoline sulfonamides, docking simulations were used. Among the fourteen new synthesized compounds, we found that compounds 4d and 4f exerted the strongest cytotoxicity against MCF-7 cells with an IC₅₀ value of 2.5 and 5 μM, respectively. Flow cytometry data revealed the ability of compounds 4d and 4f to mediate apoptosis and arrest cell cycle growth at G1 phase. Furthermore, RT-PCR and Western blot results suggested that both 4d and 4f activates apoptotic cell death pathway in MCF-7 cells. Molecular docking assessments indicated that compounds 4d and 4f fit perfectly into Bcl2's active site. Based on the biological properties, we conclude that both compounds 4d and 4f could be used as a new type of anticancer agent, which provides a scientific basis for further research into the treatment of cancer.

Knockout of caspase-7 gene improves the expression of recombinant protein in CHO cell line through the cell cycle arrest in G2/M phase

Background

Chinese hamster ovary cell line has been used routinely as a bioproduction factory of numerous biopharmaceuticals. So far, various engineering strategies have been recruited to improve the production efficiency of this cell line such as apoptosis engineering. Previously, it is reported that the caspase-7 deficiency in CHO cells reduces the cell proliferation rate. But the effect of this reduction on the CHO cell productivity remained unclear. Hence, in the study at hand the effect of caspase-7 deficiency was assessed on the cell growth, viability and protein expression. In addition, the enzymatic activity of caspase-3 was investigated in the absence of caspase-7.

Results

Findings showed that in the absence of caspase-7, both cell growth and cell viability were decreased. Cell cycle analysis illustrated that the CHO knockout (CHO-KO) cells experienced a cell cycle arrest in G2/M phase. This cell cycle arrest resulted in a 1.7-fold increase in the expression of luciferase in CHO-KO cells compared to parenteral cells. Furthermore, in the apoptotic situation the enzymatic activity of caspase-3 in CHO-KO cells was approximately 3 times more than CHO-K1 cells.

Conclusions

These findings represented that; however, caspase-7 deficiency reduces the cell proliferation rate but the resulted cell cycle arrest leads to the enhancement of recombinant protein expression. Moreover, increasing in the caspase-3 enzymatic activity compensates the absence of caspase-7 in the caspase cascade of apoptosis.

The Immunogenetics of Vitiligo: An Approach Toward Revealing the Secret of Depigmentation

Vitiligo is a hypomelanotic skin disease and considered to be of autoimmune origin due to breaching of immunological self-tolerance, resulting in inappropriate immune responses against melanocytes. The development of vitiligo includes a strong heritable component. Different strategies ranging from linkage studies to genome-wide association studies are used to explore the genetic factors responsible for the disease. Several vitiligo loci containing the respective genes have been identified which contribute to vitiligo and genetic variants for some of the genes are still unknown. These genes include mainly the proteins that play a role in immune regulation and a few other genes important for apoptosis and regulation of melanocyte functions. Despite the available data on genetic variants and risk alleles which influence the biological processes, only few immunological pathways have been found responsible for all ranges of severity and clinical manifestations of vitiligo. However, studies have concluded that vitiligo is of autoimmune origin and manifests due to complex interactions in immune components and their inappropriate response toward melanocytes. The genes involved in the immune regulation and processing the melanocytes antigen and its presentation can serve as effective immune-therapeutics that can target specific immunological pathways involved in vitiligo. This chapter highlights those immune-regulatory genes involved in vitiligo susceptibility and loci identified to date and their implications in vitiligo pathogenesis.

Intestinal UDP-Glucuronosyltransferase 1A1 and Protection against Irinotecan-Induced Toxicity in a Novel UDP-Glucuronosyltransferase 1A1 Tissue-Specific Humanized Mouse Model

The human UDP-glucuronosyltransferases (UGTs) represent an important family of drug-metabolizing enzymes, with UGT1A1 targeting the conjugation and detoxification of many exogenous substances, including pharmaceutical drugs. In this study we generated humanized UGT1A1 mice expressing the human UGT1A1 gene in either liver (hUGT1A1^HEP ) or intestine (hUGT1A1^GI ), enabling experiments to examine tissue-specific properties of UGT1A1-specific glucuronidation. Hepatic and intestinal tissue-specific expression and function of UGT1A1 were demonstrated. Although the liver is considered a major organ for detoxification, intestinal UGT1A1 is an important contributor for drug clearance. Mice were challenged with irinotecan (CPT-11), a prodrug hydrolyzed by carboxylesterases to form the active metabolite 7-ethyl-10-hydroxycamptothecin (SN-38) and detoxified by UGT1A1. Humanized UGT1A1^HEP mice that have no intestinal UGT1A1 displayed a greater lethality rate when exposed to CPT-11 than hUGT1A1^GI mice. When exposed to a low dose of CPT-11 (10 mg/kg), hUGT1A1^HEP mice displayed greater intestinal inflammatory (IL-1β and IL-6) insult in addition to p53-triggered apoptotic responses. In vitro studies with intestinal crypt organoids exposed to CPT-11 confirmed the results observed in vivo and indicated that CPT-11 impacts stemness, apoptosis, and endoplasmic reticulum (ER) stress in organoids deficient in UGT1A1. When we examined the induction of ER stress in organoids with thapsigargin, an inhibitor of sarco/endoplasmic reticulum Ca²⁺ ATPase, apoptosis and the caspase surge that occurred in hUGT1A1^HEP mice were blocked in hUGT1A1^GI organoids. This study reveals the importance of intestinal UGT1A1 in preventing inflammation, apoptosis, and loss of stemness capacity upon systemic challenge with an important chemotherapeutic agent. SIGNIFICANCE STATEMENT: Hepatic and intestinal UGT1A1 play a key role in the metabolism and detoxification of endogenous and exogenous compounds. The use of tissue-specific humanized models expressing UGT1A1 in liver or intestine has confirmed the relevance of the intestinal tract in the detoxification of irinotecan. Mechanistic studies using intestinal organoids highlighted the importance of UGT1A1 in reducing inflammation, apoptosis, and loss of stemness. These new models provide valuable tools for studying tissue-specific glucuronidation of substances that are metabolized by human UGT1A1.

Cordyceps militaris extract induces apoptosis and pyroptosis via caspase-3/PARP/GSDME pathways in A549 cell line

Cordyceps militaris (CM) is traditionally used as dietary therapy for lung cancer patients in China. CM extract (CME) is hydrosoluble fraction of CM and extensively investigated. Caspase-3-involved cell death is considered as its major anticancer mechanism but inconclusive. Therefore, we explore its caspase-3-dependent programmed cell death nature (apoptosis and pyroptosis) and validate its caspase-3-dependent property in loss-of-function experiment. Component profile of CME is detected by High Performance Liquid Chromatography- quadrupole time-of-flight mass spectrometry (HPLC-qTOF). Results show that CME causes pyroptosis-featured cell bubbling and cell lysis and inhibits cell proliferation in A549 cell. CME induces chromatin condensing and makes PI+/annexin V+ staining in bubbling cells, indicating genotoxicity, apoptosis, and pyroptosis cell death are caused by CME. High concentration of CME (200 μg/ml) exerts G2/M and G0 cell cycles arresting and suppresses P53-downstream proliferative proteins, including P53, P21, CDC25B, CyclinB1, Bcl-2, and BCL2 associated agonist of cell death (BAD), but 1-100 μg/ml of CME show less effect on proteins above. Correspondingly, caspase-3 activity and caspase-3 downstream proteins including pyroptotic effector gasdermin-E (GSDME) and apoptotic marker cleaved-poly-ADP-ribose polymerase (PARP) are significantly promoted by CME. Moreover, regarding membrane pore formation in pyroptotic cell, expression of membrane GSDME (GSDME antibody conjugated with PE-Cy7 for detection in flow cytometry) is remarkably increased by CME treatment. By contrast, other pyroptosis-related proteins such as P2X7, NLRP3, GSDMD, and Caspase-1 are not affected after CME treatment. Additionally, TET2 is unexpectedly raised by CME. In present of caspase-3 inhibitor Ac-DEVD-CHO (Ac-DC), CME-induced cytotoxicity, cell bubbling, and genotoxicity are reduced, and CME-induced upregulation of apoptosis (cleaved-PARP-1) and pyroptosis (GSDME-NT) proteins are reversed. Lastly, 22 components are identified in HPLC-qTOF experiment, and they are classified into trophism, neoadjuvant component, cytotoxic component, and cancer deterioration promoter according to previous references. Conclusively, CME causes caspase-3-dependent apoptosis and pyroptosis in A549 through caspase-3/PARP and caspase-3/GSDME pathways, and it provides basic insight into clinic application of CME for cancer patients.

The use of HRM shifts in qPCR to investigate a much neglected aspect of interference by intracellular nanoparticles

Genetic molecular studies used to understand potential risks of engineered nanomaterials (ENMs) are incomplete. Intracellular residual ENMs present in biological samples may cause assay interference. This report applies the high-resolution melt (HRM) feature of RT-qPCR to detect shifts caused by the presence of gold nanoparticles (AuNPs). A universal RNA standard (untreated control) sample was spiked with known amounts of AuNPs and reverse transcribed, where 10 reference genes were amplified. The amplification plots, dissociation assay (melt) profiles, electrophoretic profiles and HRM difference curves were analysed and detected interference caused by AuNPs, which differed according to the amount of AuNP present (i.e. semi-quantitative). Whether or not the assay interference was specific to the reverse transcription or the PCR amplification step was tested. The study was extended to a target gene-of-interest (GOI), Caspase 7. Also, the effect on in vitro cellular samples was assessed (for reference genes and Caspase 7). This method can screen for the presence of AuNPs in RNA samples, which were isolated from biological material in contact with the nanomaterials, i.e., during exposure and risk assessment studies. This is an important quality control procedure to be implemented when quantifying the expression of a GOI from samples that have been in contact with various ENMs. It is recommended to further examine 18S, PPIA and TBP since these were the most reliable for detecting shifts in the difference curves, irrespective of the source of the RNA, or, the point at which the different AuNPs interacted with the assay.