Advances in the Application of Apoptotic Proteins and Alternative Splicing in Tumor Therapy: A Narrative Review.

An apoptosis-resistant state determined by apoptotic protein expression is commonly seen in the initiation, progression, and treatment failure stages of human cancer, and anti-tumor drugs targeting apoptotic proteins have been increasingly developed over the past three decades. However, the frequently alternative splicing of apoptotic proteins diminished the ability of targeting drugs to bind to apoptotic proteins and, consequently, limit the drug efficacy. Currently, accumulating evidence has demonstrated that many alternative splicing events have been associated to apoptosis resistance in different cancers. Therefore, the intervention targeting alternative splicing for regulating tumor cell apoptosis is expected to become a new strategy and new direction of antitumor therapy. Here, we present well established alternative splicing events that occur in different apoptosis-related genes and their modification by several approaches with cancer therapeutic purposes.

(2E)-1-(2,4,6-Trimethoxyphenyl)-3-(4-chlorophenyl)prop-2-en-1-one, a Chalcone Derivative, Promotes Apoptosis by Suppressing RAS-ERK and AKT/FOXO3a Pathways in Hepatocellular Carcinoma Cells.

BACKGROUND: Liver cancer is an extremely common cancer with the highest mortality rate and poor prognosis. Owing to their low systemic toxicity and few side effects, natural compounds may provide better therapeutic effects for patients. (2E)-1-(2,4,6-trimethoxyphenyl)-3-(4-chlorophenyl)prop-2-en-1-one (TMOCC), a chalcone derivative, exhibits cytotoxicity towards many tumor cells. However, the anticancer mechanism of TMOCC has not been elucidated in human hepatocellular carcinoma (HCC). METHODS: Cell Counting Kit-8 and colony formation assays were used to evaluate the effects of TMOCC on viability and proliferation. Mitochondrial transmembrane potential and flow cytometry assays were used to detect apoptosis. The expression levels of proteins related to apoptosis, the RAS-ERK and AKT/FOXO3a signaling pathways were assessed using western blot. Potential targets of TMOCC were detected using molecular docking analysis. RESULTS: TMOCC inhibited viability and proliferation, and induced the loss of mitochondrial transmembrane potential, apoptosis and DNA double-strand breaks in both HCC cells. The RAS-ERK and AKT/FOXO3a signaling pathways were suppressed by TMOCC. Finally, ERK1, PARP-1, and BAX were identified as potential targets of TMOCC. CONCLUSION: Taken together, our results show that TMOCC promotes apoptosis by suppressing the RAS-ERK and AKT/FOXO3a signaling pathways. TMOCC may be a potential multi-target compound that is effective against liver cancer.

Estimation and sensitivity analysis of a COVID-19 model considering the use of face mask and vaccination.

To model the COVID-19 infection and develop effective control measures, this paper proposes an SEIR-type epidemic model considering the impact of face-mask wearing and vaccination. Firstly, the effective reproduction number and the threshold conditions are obtained. Secondly, based on the data of South Korea from January 20, 2022 to March 21, 2022, the model parameters are estimated. Finally, a sensitivity analysis and the numerical study are conducted. The results show that the face-mask wearing is associated with [Formula: see text] and [Formula: see text] reductions in the numbers of cumulative cases and newly confirmed cases, respectively, after a period of 60 days, when the face mask wearing rate increases by [Formula: see text]. Furthermore, the vaccination rate is associated with [Formula: see text] and [Formula: see text] reductions in the numbers of cumulative cases and the newly confirmed cases, respectively, after the same period of 60 days when the vaccination rate is increased by [Formula: see text]. A combined measure involving face-mask wearing and vaccination may be more effective and reasonable in preventing and controlling this infection. It is also suggested that disease control departments should strongly recommended the wearing of face masks s as well as vaccination to prevent the unvaccinated people from becoming infected.

FOXP3 and SQSTM1/P62 correlate with prognosis and immune infiltration in hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common highly malignant tumours worldwide. FOXP3 and SQSTM1/P62 have been shown to be abnormally expressed in tumour cells, but their function in different tumours remains controversial. The present study was designed to evaluate the expression of FOXP3 and P62 in HCC and their prognostic value as well as their relationship with immune infiltration in HCC patients. METHODS: The Gene Expression Omnibus (GEO) database and TNMplot.com platform were used to analyse the expression of FOXP3 and P62. The Cancer Genome Atlas (TCGA) database and Kaplan-Meier plotter were used to assess the impacts of FOXP3 and P62 on clinical prognosis. In addition, TCGA database was also used to examine the correlation between the expression of FOXP3 and P62 and tumour immune infiltration using the CIBERSORT algorithm. Finally, immunohistochemistry (IHC) was used to determine expression levels of FOXP3 and P62 in 89 HCC and adjacent normal liver tissues, and their effects on clinicopathological features and prognosis were verified. RESULTS: FOXP3 expression was downregulated in HCC tissues, while P62 expression was upregulated. FOXP3 underexpression and P62 overexpression were closely related to decreased overall survival (OS) in HCC patients. Additionally, the abnormal expression of FOXP3 and P62 was closely related to the infiltration levels of 12 types of immune cells, including regulatory T cells (Tregs), M2 macrophages, M0 macrophages, and CD8 T cells. Notably, in the validation model, abnormal FOXP3 and P62 expression was significantly associated with adverse clinicopathological factors in HCC patients, including elevated α-fetoprotein (AFP) levels, poor tumour differentiation, and increased Ki67 levels. Furthermore, low FOXP3 and high P62 expression were independent risk factors for predicting OS prognosis in HCC patients. CONCLUSION: FOXP3 and P62 have been shown to be important prognostic factors in HCC patients and are associated with immune cell infiltration in HCC. These findings suggest that FOXP3 and P62 may be valuable prognostic biomarkers and potential therapeutic targets for HCC treatment.

Dynamic variations of the gastric microbiota: Key therapeutic points in the reversal of Correa's cascade.

Correa's cascade is a dynamic process in the development of intestinal-type gastric cancer (GC), and its pathological features, gastric microbiota and interactions between microorganisms and their hosts vary at different developmental stages. The characteristics of cells, tissues and gastric microbiota before or after key therapeutic points are critical for monitoring malignant transformation and early tumour reversal. This review summarises the pathological features of gastric mucosa, characteristics of gastric microbiota, specific microbial markers, microbe-microbe interactions and microbe-host interactions at different stages in Correa's cascade. The markers related to each Correa's cascade point were analysed in detail. We attempted to identify key therapeutic points for early cancer reversal and provide a novel approach to reduce the incidence of GC and improve precise treatment.

Alterperylenol as a Novel Thioredoxin Reductase Inhibitor Induces Liver Cancer Cell Apoptosis and Ferroptosis.

Natural products are a rich resource for discovering innovational drugs. Herein, we isolated and characterized two compounds dihydroalterperylenol (DAP) and alterperylenol (AP) from Alternaria sp. MG1, an endophytic fungus isolated from Vitis quinquangularis, and investigated the underlying antitumor mechanism of AP. Mechanistically, AP inhibits the growth of HepG2 cells by targeting the selenoprotein thioredoxin reductase (TrxR) and ultimately induces cell apoptosis and ferroptosis. Compared to DAP, the α,ß-unsaturated carbonyl structure of AP is an indispensable moiety for its antitumor activity and TrxR inhibition. Specifically, inhibition of TrxR causes the extensive reactive oxygen species and consequently results in DNA damage, G2/M cell cycle arrest, and mitochondrial fission. Furthermore, ferroptosis is driven via excess toxic lipid peroxidation and elevation of intracellular iron levels via regulating iron-related proteins. In vivo validation also shows that AP owns anticancer activity in xenograft mice. Collectively, our results disclose a novel natural TrxR inhibitor AP exerting the antitumor effect via inducing cell apoptosis and ferroptosis and evidence that AP is a promising candidate agent for liver carcinoma therapy. The link of TrxR inhibition to ferroptosis further highlights the physiological importance of TrxR in regulating ferroptosis.

The Global research of protein post-translational modifications in the cancer field: A bibliometric and visualized study.

Objectives: Protein post-translational modifications (PTMs) are closely associated with tumorigenesis, targeting PTMs of key proteins might be the focus of antitumor drug discovery. This study aimed to analyze the research progress on protein PTMs in tumorigenesis by performing qualitative and quantitative evaluations. Methods: The Web of Science Core Collection was selected as the database, and Science Citation Index Expanded was selected as the citation index. Visualization tools such as VOSviewer, CiteSpace, HistCite, and Online Analysis Platform of Bibliometrics were used to deeply explore the information of the retrieved research papers and analyze them in terms of research trends and main aspects of research. Results: The search yielded 3777 relevant articles. The results showed that the total number of PTMs related papers in cancer field has been increasing annually, with the largest number of papers published in the United States of America. The co-word cluster analysis showed that the research on PTMs and tumorigenesis was primarily focused on the following four areas, mechanism, histone, P53, key Technologies. Tumor metabolism, autophagy, and protein-protein interaction, histone ubiquitination have become new research topics. Conclusion: This study provides an important reference for the research direction and selection of topics of interest in the PTMs of cancer field.

Huc-MSC-derived exosomes modified with the targeting peptide of aHSCs for liver fibrosis therapy.

BACKGROUND: Effective therapeutics to stop or reverse liver fibrosis have not emerged, because these potential agents cannot specifically target activated hepatic stellate cells (aHSCs) or are frequently toxic to parenchymal cells. Human umbilical cord mesenchymal stem cell (Huc-MSC)-derived exosomes show promise in nanomedicine for the treatment of liver fibrosis. However, systemic injection showed that unmodified exosomes were mainly taken up by the mononuclear phagocyte system. The discovery of ligands that selectively bind to a specific target plays a crucial role in clinically relevant diagnostics and therapeutics. Herein, we aimed to identify the targeting peptide of aHSCs by screening a phage-displayed peptide library, and modify Huc-MSC-derived exosomes with the targeting peptide. RESULTS: In this study, we screened a phage-displayed peptide library by biopanning for peptides preferentially bound to HSC-T6 cells. The identified peptide, HSTP1, also exhibited better targeting ability to aHSCs in pathological sections of fibrotic liver tissues. Then, HSTP1 was fused with exosomal enriched membrane protein (Lamp2b) and was displayed on the surface of exosomes through genetic engineering technology. The engineered exosomes (HSTP1-Exos) could be more efficiently internalized by HSC-T6 cells and outperformed both unmodified exosomes (Blank-Exos) and Lamp2b protein overexpressed exosomes (Lamp2b + Exos) in enhancing the ability of exosomes to promote HSC-T6 reversion to a quiescent phenotype. In vivo results showed HSTP1-Exos could specifically target to the aHSC region after intravenous administration, as demonstrated by coimmunofluorescence with the typical aHSCs marker α-SMA, and enhance the therapeutic effect on liver fibrosis. CONCLUSION: These results suggest that HSTP1 is a reliable targeting peptide that can specifically bind to aHSCs and that HSTP1-modified exosomes realize the precise treatment for aHSCs in complex liver tissue. We provide a novel strategy for clinical liver fibrosis therapy.

Gold Nanorods-Based Photothermal Therapy: Interactions Between Biostructure, Nanomaterial, and Near-Infrared Irradiation.

Gold nanorods (AuNRs) are ideal inorganic nanophotothermal agents with unique characteristics, including local surface plasmon resonance effects, easy scale preparation and functional modification, and good biocompatibility. This review summarizes several recent advances in AuNRs-based photothermal therapy (PTT) research. Functionalized AuNRs photothermal agents have optimized biocompatibility and targeting properties. The multifunctional AuNRs nanoplatform composite structure meets the requirements for synergistic effects of PTT, photoacoustic imaging, and other therapeutic methods. Photothermal therapy with AuNRs (AuNRs-PTT) is widely used to treat tumors and inflammatory diseases; its tumor-targeting, tumor metastasis inhibition, and photothermal tumor ablation abilities have remarkable curative effects. An in-depth study of AuNRs in living systems and the interactions between biological structure, nanomaterial, and near-infrared irradiation could lay the foundation for further clinical research and the broad application of AuNRs in PTT.

Dual role of cadmium in rat liver: Inducing liver injury and inhibiting the progression of early liver cancer.

The heavy metal cadmium (Cd) can induce damage in liver and liver cancer cells; however, the mechanism underlying its toxicity needs to be further verified in vivo. We daily administered CdCl2 to adult male rats at different dosages via gavage for 12 weeks and established rat liver injury model and liver cancer model to study the dual role of Cd in rat liver. Increased exposure to Cd resulted in abnormal liver function indicators, pathological degeneration, rat liver cell necrosis, and proliferation of collagen fibres. Using immunohistochemistry, we found that the area of GST-P-positive precancerous liver lesions decreased in a dose-dependent manner. Real-time quantitative polymerase chain reaction, western blot, immunohistochemistry, and transmission electron microscopy revealed that Cd induced mitophagy, as well as mitophagy blockade, as evidenced by the downregulation of TOMM20 and upregulation of LC3II and P62 with increasing Cd dose. Next, the expression of PINK1/Parkin, a classic signalling pathway protein that regulates mitophagy, was examined. Cd was found to promote PINK1/Parkin expression, which was proportional to the Cd dose. In conclusion, Cd activates PINK1/Parkin-mediated mitophagy in a dose-dependent manner. Mitophagy blockade likely aggravates Cd toxicity, leading to the dual role of inducing liver injury and inhibiting the progression of early liver cancer.

Comparison of the community-acquired pneumonia and COVID-19 at the early stage: findings from two cohort studies.

BACKGROUND: The current focus is largely on whole course medical management of coronavirus disease-19 (COVID-19) with real-time polymerase chain reaction (RT-PCR) and radiological features, while the mild cases are usually missed. Thus, combination of multiple diagnostic methods is urgent to understand COVID-19 fully and to monitor the progression of COVID-19. METHODS: laboratory variables of 40 mild COVID-19 patients, 30 patients with community-acquired pneumonia (CAP) and 32 healthy individuals were analyzed by principal component analysis (PCA), Kruskal test, Procrustes test, the vegan package in R, CCA package and receiver operating characteristic to investigate the characteristics of the laboratory variables and their relationships in COVID-19. RESULTS: The correlations between the laboratory variables presented a variety of intricate linkages in the COVID-19 group compared with the healthy group and CAP patient group. The prediction probability of the combination of lymphocyte count (LY), eosinophil (EO) and platelets (PLT) was 0.847, 0.854 for the combination of lactate (LDH), creatine kinase isoenzyme (CK-MB), and C-reactive protein (CRP), 0.740 for the combination of EO, white blood cell count (WBC) and neutrophil count (NEUT) and 0.872 for the combination of CK-MB and P. CONCLUSIONS: The correlations between the laboratory variables in the COVID-19 group could be a unique characteristic showing promise as a method for COVID-19 prediction and monitoring progression of COVID-19 infection.

Transcription profiling of cadmium-exposed livers reveals alteration of lipid metabolism and predisposition to hepatic steatosis.

1. Cadmium (Cd) is a ubiquitous environmental toxicant that can cause liver steatosis and nonalcoholic fatty liver disease (NAFLD) on long-term exposure.2. Sixteen Sprague Dawley rats were randomly divided into two groups, and were administered normal saline and 5 mg/(kg·d) cadmium chloride by gavage. In vitro, BRL3A cells, a rat normal liver cell line, were treated with different concentrations of Cd to verify the sequencing results.3. The RNA-seq revealed 146 upregulated genes and 127 downregulated genes in the Cd intervention group. The key genes of lipid metabolism were significantly overexpressed, such as Cyp1a1 and Pla2g2d. The GO enrichment analysis showed that the 'sterol biosynthetic process' was the most obvious difference. The KEGG analysis showed that six of the top 10 differential pathways were related to lipid metabolism. The expression of the essential genes in BRL3A was consistent with the sequencing results. The protein-protein interaction (PPI) yielded that Cyp1a1 is in the central region of the differentially expressed gene network.4. The chronic Cd exposure is still an important environmental health problem with a probable tendency to cause NAFLD. It may possibly act by affecting the lipid metabolism in the liver, especially the synthesis and decomposition of unsaturated fatty acids.

Effect of Helicobacter Pylori on Plasma Metabolic Phenotype in Patients With Gastric Cancer.

BACKGROUND: Although Helicobacter pylori (Hp) as high risk factor for gastric cancer have been investigated from human trial, present data is inadequate to explain the effect of Hp on the changes of metabolic phenotype of gastric cancer in different stages. PURPOSE: Herein, plasma of human superficial gastritis (Hp negative and positive), early gastric cancer and advanced gastric cancer analyzed by UPLC-HDMS metabolomics can not only reveal metabolic phenotype changes in patients with gastric cancer of different degrees (30 Hp negative, 30 Hp positive, 20 early gastric cancer patients, and 10 advanced gastric cancer patients), but also auxiliarily diagnose gastric cancer. RESULTS: Combined with multivariate statistical analysis, the results represented biomarkers different from Hp negative, Hp positive, and the alterations of metabolic phenotype of gastric cancer patients. Forty-three metabolites are involved in amino acid metabolism, and lipid and fatty acid metabolism pathways in the process of cancer occurrence, especially 2 biomarkers glycerophosphocholine and neopterin, were screened in this study. Neopterin was consistently increased with gastric cancer progression and glycerophosphocholine tended to consistently decrease from Hp negative to advanced gastric cancer. CONCLUSION: This method could be used for the development of rapid targeted methods for biomarker identification and a potential diagnosis of gastric cancer.

N-trans-Feruloyloctopamine Wakes Up BBC3, DDIT3, CDKN1A, and NOXA Signals to Accelerate HCC Cell Apoptosis.

N-trans-Feruloyloctopamine (FO), a natural compound, was reported in our previous study to inhibit a tumor cell malignant phenotype by AKT- and EMT-related signals and might be used as a promising drug for HCC treatment. However, the specific targets and detailed mechanisms still need to be clarified. Screening with RNA-Seq in Huh7 cells treated with FO revealed that 317 genes were modulated, of which 188 genes were upregulated and 129 genes were downregulated. Real-time cell analyzer and flow cytometry data reveal that tumor cell proliferation and apoptosis were impacted by FO. DAVID bioinformatic data showed that most of the biological process GO terms are related to proliferation and apoptosis. KEGG enrichment analysis showed that FO mainly regulates PI3K-AKT- and apoptosis-related signals, in which BBC3, DDIT3, NOXA, and CDKN1A on the surface serve as the novel targets of FO inducing HCC cell apoptosis. The result implied that FO might exacerbate HCC cell apoptosis by regulating BBC3, DDIT3, CDKN1A, and NOXA signals. The obstacle effect of FO can provide new targets and new credibility for the treatment of liver cancer.

MicroRNA polymorphism: A target for diagnosis and prognosis of hepatocellular carcinoma?

Hepatocellular carcinoma (HCC) is a life-threatening cancer of the digestive system, with complex pathogenesis affected by a broad spectrum of genetic and epigenetic factors. Among several factors, microRNAs (miRNAs), which are considered regulators of the post-transcriptional gene expression, play important roles in determining the malignant phenotype of HCC. In recent years, the advances in molecular genetics have resulted in the characterization of complex genetic factors and in the identification of epigenetic mechanisms of diseases. Accumulating data have suggested that miRNA polymorphisms are involved in tumorigenesis and prognosis, suggesting that the miRNAs may serve as a target for HCC with regard to pathogenesis and prognosis. In the present review, a comprehensive and detailed literature search was conducted and the role of miRNA polymorphisms in the pathogenesis and prognosis of HCC is summarized. The data proposed the use of miRNAs as targets for the diagnosis and treatment of HCC.

Fabrication of silver nanoparticles/gelatin hydrogel system for bone regeneration and fracture treatment.

The present work aims to examine the effect of gelatin on the stabilization of silver nanoparticles (AgNPs) and their use in healing the bone fracture. AgNPs-loaded Gel hydrogels (AgNPs/Gel) were fabricated under sunlight using gelatin (Gel) as stabilizing agent. The characterization of the synthesized hydrogels was performed with the help of techniques such as UV-visible spectroscopy (UV-Vis) and high-resolution transmission electron microscopy (HR-TEM). Furthermore, the results of cell cytotoxicity confirmed that the AgNPs/Gel hydrogels are nonhazardous to osteoblasts. The outcome of cell fixation with AgNPs/Gel hydrogels after an incubation period of five days exposed the improved survival and spreading of osteoblasts cells on the prepared AgNPs/Gel hydrogels. Moreover, the AgNPs/Gel hydrogel nanostructures displayed their ability in modulating bone fracture healing, which suggests their potential use in nursing care.

Cadmium causes hepatopathy by changing the status of DNA methylation in the metabolic pathway.

Toxicity caused by the heavy metal Cadmium leads to liver diseases; this finding has generated interest among researchers. We detected DNA methylation using Whole Genome Bisulfite Sequencing (WGBS) to study the relationship between Cadmium exposure and liver damage. Forty-eight Sprague-Dawley rats were randomly divided into six groups, and given normal saline or 2.5, 5, 10, 20, and 40 mg/kg body weight per day CdCl2 by gavage. Twelve weeks later, their liver tissues were collected for pathological examination and DNA extraction. Increased exposure to Cadmium led to a reduction in the amount of weight gain as well as pathological degeneration and necrosis of liver cells of the rats. Using WGBS, we found that DNA methylation changes in the high-dose exposure group were more remarkable, and most of the changes occurred in the gene promoter region. GO enrichment analysis showed that the genes were enriched in the biological process of "response to stimulus." KEGG analysis revealed that metabolic pathways, like MAPK, PI3K-Akt and cAMP, had the largest number of enriched genes. Using Integrative Genomics Viewer (IGV), the demethylation of F2rl3 after Cadmium poisoning was established. This finding may explain why there are changes in liver metabolism after Cadmium poisoning.

Loss of neuropilin1 inhibits liver cancer stem cells population and blocks metastasis in hepatocellular carcinoma via epithelial-mesenchymal transition.

It is generally believed that the existence of cancer stem cells (CSCs) is related to tumor recurrence and metastasis of hepatocellular carcinoma (HCC). Neuropilin1 (NRP1) is involved in numerous pathophysiological processes of tumor progression, however, whether NRP1 is involved in the regulation of liver CSCs and metastasis of HCC is still unknown. In the present study, we examined the effect of NRP1 on the population of liver CSCs and the metastasis mechanism of HCC. In NRP1 small hairpin RNA (shRNA)-transduced HCC cells, liver CSCs surface markers (CD133+/ EpCAM+/CD13+/CD44+) expressing cells, which imply the CSCs population, were decreased. Transwell assay and nude mouse liver orthotopic transplantation model confirmed that NRP1 knockdown inhibited HCC cells' migration and lung metastasis. Our data showed that the expression of NRP1 was upregulated in 5 independent cohorts of HCC patients, consequently, high levels of NRP1 correlated with recurrence and poor prognosis in HCC. Mechanism research showed that NRP1 promotes cell spreading through the epithelial-mesenchymal transition (EMT) signaling pathway. In summary, NRP1 enhanced the population of liver CSCs and migration of HCC via EMT, indicating that NRP1 might be a novel target for HCC treatments.

Modification of Mcl-1 alternative splicing induces apoptosis and suppresses tumor proliferation in gastric cancer.

Splicing dysregulation, which leads to apoptosis resistance, has been recognized as a major hallmark for tumorigenesis and cancer progression. Targeting alternative splicing by either increasing pro-apoptotic proteins or inhibiting anti-apoptotic proteins in tumor cells may be an effective approach for gastric cancer (GC) therapy. However, the role of modulation of alternative splicing in GC remains poorly understood. In this study, to the best of our knowledge, the unbalanced expression of the myeloid cell leukemia-1 (Mcl-1) splicing variants, Mcl-1L and Mcl-1S, was identified in GC patients for the first time. Increasing anti-apoptotic Mcl-1L and decreasing pro-apoptotic Mcl-1S expression levels were correlated with tumor proliferation and poor survival. In vitro data showed that a shift in splicing from Mcl-1L to Mcl-1S induced by treatment with Mcl-1-specific steric-blocking oligonucleotides (SBOs) efficiently decreased Mcl-1L expression, increased Mcl-1S expression, and accelerated tumor cell apoptosis in a dose-dependent manner. Additionally, mouse xenotransplant models confirmed that modification of Mcl-1 alternative splicing increased tumor cell death and suppressed tumor proliferation. This study demonstrated that the modification of Mcl-1 splicing might stimulate the pro-apoptotic factor and inhibit the anti-apoptotic protein to induce significant apoptosis. Thus, this finding provided a strategy for cancer therapy, according to which SBOs could be used to change the Mcl-1 splicing pattern, thereby inducing apoptosis.

Detecting cadmium during ultrastructural characterization of hepatotoxicity.

BACKGROUND: The threat of cadmium (Cd), which is the cause of itai-itai disease in Japan, is still complicated and confusing, especially for digestive system, such as liver disease. One of the most keys of this problem is demonstrating that the hepatotoxicity is indeed induced by Cd. Therefore, we attempt detecting Cd at microscale during ultrastructural imaging of liver tissue. METHODS: 12 rats were divided randomly into two experimental groups: control and Cd-treated. Treated rats were intraperitoneal injected with 1 mg/kg body weight cadmium chloride (CdCl2) for 4 weeks (5 P.M each day for 6 days/week). At the end of the exposure period, liver tissue samples were processed into ultrathin sections for analysis of advanced analytical transmission electron microscopy and X-ray energy dispersive spectroscopy (TEM/X-EDS) investigations. Ultrastructural images and X-ray energy dispersive spectrum were acquired at microscale. RESULTS: Cd can cause changes in the structure of the organelle, including the collapse of the membrane structure in the cell, the destruction of the internal structure of the organelle, the mitochondrial swelling, the expansion of the endoplasmic reticulum, and the appearance of inclusions. Cadmium bioaccumulation is detected in the mitochondria at microscale by TEM/X-EDS, which is the visual evidence of morphological changes of mitochondria related to Cd. CONCLUSION: The combination of detailed ultrastructure and microscale X-ray energy dispersive spectroscopy (X-EDS) characterization of cadmium hepatotoxicity demonstrate that cadmium indeed leads to mitochondrial damage, which is helpful for further investigation of the pathological mechanism of cadmium hepatotoxicity.