Current Molecular Medicine - Volume 25, Issue 1, 2025

Colorectal cancer (CRC) is a malignant tumor. Slug has been found to display a key role in diversified cancers, but its relevant regulatory mechanisms in CRC development are not fully explored.

Hence, exploring the function and regulatory mechanisms of Slug is critical for the treatment of CRC.

Protein expressions of Slug, N-cadherin, E-cadherin, Snail, HIF-1α, SUMO-1, Drp1, Opa1, Mfn1/2, PGC-1α, NRF1, and TFAM were measured through western blot. To evaluate the protein expression of Slug and SUMO-1, an immunofluorescence assay was used. Cell migration ability was tested through transwell assay. The SUMOylation of Slug was examined through CO-IP assay.

Slug displayed higher expression and facilitated tumor metastasis in CRC. In addition, hypoxia treatment was discovered to upregulate HIF-1α, Slug, and SUMO-1 levels, as well as induce Slug SUMOylation. Slug SUMOylation markedly affected mitochondrial biosynthesis, fusion, and mitogen-related protein expression levels to trigger mitochondrial stress. Additionally, the induced mitochondrial stress by hypoxia could be rescued by Slug inhibition and TAK-981 treatment.

Our study expounded that hypoxia affects mitochondrial stress and facilitates tumor metastasis of CRC through Slug SUMOylation.

The pathology of Parkinson's disease (PD) indicates that iron deposition exists in dopaminergic neurons, which may be related to the death of cellular lipid iron peroxide. The extracellular autophagy adaptor SQSTM1(p62) of dopamine (DA) neurons can activate the intracellular Keap1-Nrf2-ARE signaling pathway to inhibit ferroptosis, which has a protective effect on DA neurons.

The objective of this study was to investigate the protective mechanism of the Keap1-Nrf2-ARE antioxidant pathway against iron death in dopaminergic neurons.

The experiment was divided into a control group (Control group), 1-methyl-4-phenylpyridiniumion control group (MPP+ Control group), p62 overexpression group (MPP+OV-p62), and p62 overexpression no-load group (MPP+ OV-P62-NC). The inhibitors brusatol and ZnPP inhibited the activation of NF-E2-related factor 2(Nrf2) and Heme oxygenase-1(HO-1), respectively, and were divided into brusatol group (MPP+OV-p62+brusatol) and ZnPP group (MPP+OV-p62+ZnPP). RT-qPCR was used to detect transfection efficiency, and Cell Counting Kit-8 (CCK8) was used to detect cell activity. FerroOrange, 2,7-Dichlorodihydrofluorescein diacetate (DCFH-DA), and Liperfluo probes were used to detect intracellular iron, reactive oxygen species (ROS), and lipid peroxidation (LPO) levels. Western Blotting detected the levels of Nrf2, HO-1, Kelch-like ECH-associated protein1 (Keap1), and their downstream Glutathione peroxidase 4(GPX4) and Acyl-CoA synthetase long-chain family member 4(ACSL4). The levels of L-Glutathione (GSH) and Malondialdehyde (MDA) were detected by GSH and MDA kits, and the activation of Keap1-Nrf2-ARE pathway was verified at the cellular level to have an antioxidant protective effect on iron death in dopaminergic neurons.

(1) The results of RT-qPCR showed that compared with the control group, the expression of the p62 gene was significantly increased in the MPP+OV-p62 groups (p = 0.039), and the p62 gene was significantly increased in the brusatol and ZnPP groups, indicating successful transfection (p =0.002; p=0.008). (2) The immunofluorescence probe flow results showed that compared to the normal control group, the contents of three kinds of probes in MPP+ model group were significantly increased (p =0.001; p <0.001; p<0.001), and the contents of three kinds of probes in MPP+OV-p62 group were decreased compared to the MPP+ model group (p =0.004). The results indicated that the levels of iron, ROS, and LPO were increased in the MPP+ group and decreased in the MPP+OV-p62 group. (3) Compared with the control group, the expressions of Nrf2, HO-1, and GPX4 in the MPP+OV-p62 group were increased (p =0.007; p =0.004; p=0.010), and the expressions of Keap1 and ACSL4 in MPP+p62 overexpression group were decreased (p =0.017; p =0.005). Compared with the MPP+ control group, Nrf2 and GPX4 were increased in the MPP+OV-p62 group, and ACSL4 was decreased in the MPP+OV-p62 group (p =0.041; p <0.001; p <0.001). The results of the GSH and MDA kit showed that compared with the normal control group, the content of GSH in the MPP+ control group was decreased (p < 0.01), and the content of MDA was increased (p < 0.01). Compared with the MPP+ model group, GSH content was increased (P = 0.003), and MDA content was decreased in the MPP+OV-p62 group (p < 0.001). Nrf2, HO-1, and GPX4 increased in the MPP+p62 overexpression group but decreased in the brusatol group and ZnPP group (p < 0.001).

Based on the transfection of P62 plasmid, it was found that P62 plasmid can inhibit the lipid peroxidation of iron death in dopaminergic nerve cells by activating the Nrf2 signaling pathway, thus playing a protective role in dopaminergic nerve cells.

Neuroblastoma (NB) is one of the most common pediatric solid tumors. Emerging evidence has indicated that ADGRL4 can act as a master regulator of tumor progression. In addition, it is well documented that the ERK/STAT3 signaling pathway can promote the proliferation, EMT, angiogenesis, and metastasis in tumors. The current study was formulated to elucidate the exact role of ADGRL4 in the malignant behaviors of NB cells and to investigate the intrinsic mechanism.

In this work, expression differences of ADGRL4 in human NB cell lines and HUVECs were assessed via RT-qPCR and western blot analysis. For functional experiments, sh-ADGRL4 was transfected into SK-N-SH cells to generate ADGRL4 knockdown stable cell line. Moreover, ADGRL4 knockdown stable SK-N-SH cells were treated with LM22B-10 (an ERK activator) for rescue experiments. CCK-8, colony formation, would healing, and transwell assays determined NB cell growth, migration, and invasion. Meanwhile, proliferation-, metastasis- and EMT- associated proteins were also detected. Additionally, a tube formation assay was employed to evaluate in vitro angiogenesis. VM-cadherin, the marker of angiogenesis, was assessed using immunofluorescence staining.

Data showed notably upregulated ADGRL4 in NB cells, especially in SK-N-SH cells. ADGRL4 knockdown inhibited NB cell growth, migration, invasion, EMT, and in vitro angiogenesis. ADGRL4 knockdown inactivated ERK/STAT3 signaling pathway. Activation of the ERK/STAT3 signaling pathway partially rescued the tumor suppression effects of ADGRL4 knockdown on NB cells.

To conclude, the downregulation of ADGRL4 may inhibit cell growth, aggressiveness, EMT, and angiogenesis in NB by inactivating the ERK/STAT3 signaling pathway.

We aimed to investigate the relationship between histone deacetylase 2 (HDAC2) and SPARC-related modular calcium binding 2 (SMOC2) and the role of SMOC2 in gallbladder cancer (GBC).

The expression of HDAC2 and SMOC2 in GBC and normal cells was detected by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR), which was also used to detect the mRNA stability of SMOC2. The combination between HDAC2 and SMOC2 was detected by Chromatin immunoprecipitation (ChIP) assay. After silencing and/or overexpressing HDAC2 and SMOC2, cell viability, migration, invasion, and stemness were respectively tested by the Cell Counting Kit-8 (CCK-8), cell scratch, transwell, and sphere-formation assay.

In GBC cells, HDAC2 and SMOC2 were highly expressed. HDAC2 combined with SMOC2 promoted mRNA stability of SMOC2. HDAC2 or SMOC2 overexpression promoted GBC cell metastasis and stemness. SMOC2 overexpression rescued the negative effects of silencing HDAC2 in GBC.

HDAC2 stabilizes SMOC2 to promote metastasis and stemness in gallbladder cancer.

Heart failure (HF) is the ultimate transformation result of various cardiovascular diseases. Mitochondria-mediated cardiomyocyte apoptosis has been uncovered to be associated with this disorder.

This study mainly delves into the mechanism of the anti-arrhythmic drug amiodarone on mitochondrial toxicity of cardiomyocytes.

The viability of H9c2 cells treated with amiodarone at 0.5, 1, 2, 3, and 4 μM was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and Sigmar1 expression was examined by quantitative real-time PCR (qRT-PCR). After transfection, the viability, apoptosis, reactive oxygen species (ROS) level, mitochondrial membrane potential (MMP), and potassium voltage-gated channel subfamily H member 2 (KCNH2) expression in H9c2 cells were assessed by MTT, flow cytometry, ROS assay kit, mitochondria staining kit, and Western blot.

Amiodarone at 1-4 μM notably weakened H9c2 cell viability with IC50 value of 2.62 ± 0.43 μM. Amiodarone at 0.5-4 μM also evidently suppressed the Sigmar1 level in H9c2 cells. Amiodarone repressed H9c2 cell viability and KCNH2 level and triggered apoptosis, ROS production and mitochondrial depolarization, while Sigmar1 up-regulation reversed its effects. Moreover, KCNH2 silencing neutralized the effect of Sigmar1 up-regulation on H9c2 cell viability, apoptosis, and ROS production.

Amiodarone facilitates the apoptosis of H9c2 cells by restraining Sigmar1 expression and blocking KCNH2-related potassium channels.

Sepsis is a life-threatening disease caused by infection, and developing novel strategies against sepsis is still required. Exosomes derived from mesenchymal stem cells (MSCs) have shown promising therapeutic potential for various diseases. In this study, we aimed to investigate the action and mechanism of exosomes derived from IL-1β-pre-conditioned bone marrow-derived mesenchymal stromal cells (BMSCs) in sepsis.

Exosomes were isolated from BMSCs that were pretreated with (IL-1β-BMSC/exos) or without IL-1β (BMSC/exos). In vitro, a cell model of sepsis was induced by treating human umbilical vein endothelial cells (HUVECs) with lipopolysaccharide (LPS), while in vivo, a sepsis model was established through cecal ligation and puncture (CLP) operation. Immunofluorescence staining was used to detect the uptake of exosomes by HUVECs. The effects of exosomes on the cellular function of HUVECs were determined through EDU proliferation assay, migration assay, and tube formation assay. Gene and protein expression were analyzed using qRT-PCR, Western blot, ELISA, immunofluorescence staining, and immuno-histochemistry staining.

IL-1β-BMSC/exos significantly enhanced the proliferation, migration, and tube formation of HUVECs. Treatment with LPS induced the expression of high mobility group box 1 (HMGB1) and the phosphorylation of AKT in HUVECs, but these effects were counteracted by the treatment of IL-1β-BMSC/exos. The protective effect of IL-1β-BMSC/exos on the viability and tube formation ability of HUVECs was reversed by overexpression of HMGB1. Moreover, IL-1β-BMSC/exos promoted the polarization of M2 macrophages and reduced the secretion of inflammatory chemokines. Additionally, IL-1β-BMSC/exos alleviated cecal ligation and puncture (CLP)-induced sepsis in vivo.

IL-1β-BMSC/exos alleviates sepsis by modulating the HMGB1/AKT pathway and triggering M2 macrophage polarization.

Neferine (Nef) has a renal protective effect. This research intended to explore the impact of Nef on hyperuricemic nephropathy (HN).

Adenine and potassium oxonate were administered to SD rats to induce the HN model. Bone marrow macrophages (BMDM) and NRK-52E were used to construct a transwell co-culture system. The polarization of BMDM and apoptosis levels were detected using immunofluorescence and flow cytometry. Renal pathological changes were detected using hematoxylin-eosin (HE) and Masson staining. Biochemical methods were adopted to detect serum in rats. CCK-8 and EDU staining were used to assess cell activity and proliferation. RT-qPCR and western blot were adopted to detect NLRC5, NLRP3, pyroptosis, proliferation, and apoptosis-related factor levels.

After Nef treatment, renal injury and fibrosis in HN rats were inhibited, and UA concentration, urinary protein, BUN, and CRE levels were decreased. After Nef intervention, M1 markers, pyroptosis-related factors, and NLRC5 levels in BMDM stimulated with uric acid (UA) treatment were decreased. Meanwhile, the proliferation level of NRK-52E cells co-cultured with UA-treated BMDM was increased, but the apoptosis level was decreased. After NLRC5 overexpression, Nef-induced regulation was reversed, accompanied by increased NLRP3 levels. After NLRP3 was knocked down, the levels of M1-type markers and pyroptosis-related factors were reduced in BMDM.

Nef improved HN by inhibiting macrophages polarized to M1-type and pyroptosis by targeting the NLRC5/NLRP3 pathway. This research provides a scientific theoretical basis for the treatment of HN.