The association between ferroptosis-related patterns and tumor microenvironment in colorectal cancer.

Ferroptosis, a form of regulated cell death (RCD), exhibits distinct characteristics such as iron-dependence and lipid peroxidation accumulation (ROS), setting it apart from other types of cell death like apoptosis and necrosis. Its role in cancer biology is increasingly recognized, particularly its potential interaction with tumor microenvironment (TME) and CD8 T cells in cancer immunotherapy. However, the impact of ferroptosis on TME cell infiltration remains unclear. In this study, we conducted unsupervised clustering analysis on patient data from public databases, identifying three ferroptosis patterns with distinct TME cell infiltration characteristics: immune-inflamed, immune-excluded, and immune-desert phenotypes. We developed a ferroptosis score based on differentially expressed genes (DEGs) among these patterns, which correlated with various biological features including chemotherapy-resistance and immune cells infiltration. Despite patients with high ferroptosis scores exhibiting worse prognosis, they showed increased likelihood of benefiting from immunotherapy. Our findings highlight the importance of ferroptosis-related patterns in understanding TME cell infiltration and suggest novel strategies for drug combinations and immune-related therapies.

Frequency of HBsAg variants in occult hepatitis B virus infected patients and detection by ARCHITECT HBsAg quantitative.

Objective: To analyze the amino acid substitution caused by mutations in the major hydrophilic region (MHR) of the S-region genes in the serum samples of occult hepatitis B virus infection (OBI), and to explore the reasons for the missed detection of HBsAg. Method: The full-length gene of the S-region in hepatitis B virus(HBV) in the chronic hepatitis B virus(CHB)(10 samples) and OBI groups(42 samples) was amplified using a lab-developed, two-round PCR amplification technology. The PCR amplification products were sequenced/clone sequenced, and the nucleotide sequences of the S-region gene in HBV were compared to the respective genotype consensus sequence. Results: Only 20 of the 42 samples in the OBI group had the S-region genes successfully amplified, with the lowest HBV DNA load of 20.1IU/ml. As S-region genes in HBV, 68 cloned strains were sequenced. In the OBI and CHB groups MHR region, with a mutation rate of 3.21% (155/4828) and 0.70% (5/710). The genetic mutation rate was significantly higher in the OBI group than in the CHB group (P<0.05). The common mutation types in the MHR region were: I126T, L162R, K122E, C124R, and C147Y.Mutations at s122, s126, and s162 were associated with subgenotypes, most of which being C genotypes. The high-frequency mutation sites L162R and K122E found in this study have not been reported in previous literature. Conclusion: The results of this study confirmed that MHR mutations can cause the missed detection of HBsAg, giving rise to OBI.

The role of ATP binding cassette (ABC) transporters in breast cancer: Evaluating prognosis, predicting immunity, and guiding treatment.

Breast cancer is currently the most prevalent form of cancer worldwide. Nevertheless, there remains limited clarity regarding our understanding of the tumor microenvironment and metabolic characteristics associated with it. ATP-binding cassette (ABC) transporters are the predominant transmembrane transporters found in organisms. Therefore, it is essential to investigate the role of ABC transporters in breast cancer. Transcriptome data from breast cancer patients were downloaded from the TCGA database. ABC transporter-related genes were obtained from the Genecards database. By LASSO regression, ABC-associated prognostic signature was constructed in breast cancer. Subsequently, immune microenvironment analysis was performed. Finally, cell experiments were performed to verify the function of ABCB7 in the breast cancer cell lines MDA-MB-231 and MCF-7. Using the ABC transporter-associated signature, we calculated a risk score for each breast cancer patient. Patients with breast cancer were subsequently categorized into high-risk and low-risk groups, utilizing the median risk score as the threshold. Notably, patients in the high-risk group exhibited significantly worse prognosis (P<0.05). Additionally, differences were observed in terms of immune cell infiltration levels, immune correlations, and gene expression of immune checkpoints between the two groups. Functional experiments conducted on breast cancer cell lines MDA-MB-231 and MCF-7 demonstrated that ABCB7 knockdown significantly diminished cell activity, proliferation, invasion, and migration. These findings emphasize the significance of understanding ABC transporter-mediated metabolic and transport characteristics in breast cancer, offering promising directions for further research and potential therapeutic interventions.

miR­135b­5p enhances the sensitivity of HER­2 positive breast cancer to trastuzumab via binding to cyclin D2.

Trastuzumab has led to a marked improvement in the outcomes of patients with human epidermal growth factor receptor 2 (HER­2)­positive breast cancer. However, the effects of trastuzumab on HER­2­positive breast cancer are limited by the emergence of its cardiotoxicside effects. MicroRNA (miR)­135b­5p has been shown to inhibit tumor metastasis in breast cancer. The present study aimed to explore the effects of miR­135b­5p overexpression on the efficacy of trastuzumab in HER­2­positive breast cancer. Reverse transcription­quantitative PCR was performed to detect the levels of miR­135b­5p. Cell viability was evaluated with a Cell Counting Kit­8 assay. Annexin V/propidium iodide staining was employed to detect the number of apoptotic cells. Flow cytometry assay was performed to investigate the cell cycle. Western blotting was used to detect the expression levels of Bax, cleaved caspase­3, Bcl­2, cyclin D2, p27Kip1 and cyclin E1. Cell migration and invasion were detected by Transwell assay. Luciferase assays were conducted to identify the target gene of miR­135b­5p. In addition, an in vivo tumor xenograft model was established. miR­135b­5p agomir significantly enhanced the anti­proliferative effect of trastuzumab on HER­2­positive breast cancer cells via the induction of apoptosis, whereas the anti­metastatic effect of trastuzumab was enhanced by miR­135b­5p agomir treatment. Subsequently, luciferase assays indicated that cyclin D2 was the direct target of miR­135b­5p, whereas overexpression of the latter arrested cell cycleduring the G0/G1 phase. Moreover, miR­135b­5p agomir notably increased the antitumor effect of trastuzumab in vivo. The data demonstrated that miR­135b­5p sensitized HER­2­positive breast cancer cells to trastuzumab in vitro and in vivo by directly binding to cyclin D2. These results suggested that the combination of miR­135b­5p with trastuzumab may be a therapeutic strategy for patients with HER­2­positive breast cancer.

[Establishment and application of quantitative detection of serum anti-carbamylated protein autoantibodies by microarray chemiluminescence immunoassay].

Objective To develope a chemiluminescence immunoassay based on microarray protein chip technology for detecting the anti-carbamylated protein (CarP) antibody. We aimed to evaluate the detection performance of this method and to explore its preliminary clinical application value of this index in patients with rheumatoid arthritis (RA). Methods A quantitative detection method for anti-CarP antibody was established to evaluate the precision, minimum detection limit, linear range and specificity of the method. The 95th position of anti-CarP antibody level in serum of 120 healthy controls was defined as the cutoff value. The anti-CarP antibody level and positive rate in RA group and non-RA group were analyzed. And the correlation between anti-CarP antibody and disease activity index in RA group was analyzed. Results The precision of this method for detecting high-level sample and low-level sample was less than 15%; The linear range could reach (3.31~1448.18) AU/mL, and there was almost no cross-reaction between anti-CarP antibody and anti-CCP antibody. Compared with healthy control group, the level of anti-CarP antibody in RA group, anti-CCP antibody positive RA group and joint pain group was significantly higher, and that in undifferentiated connective tissue disease group was also higher. Compared with the 5% positive rate of anti-CarP antibody in healthy control group, the positive rate of RA patients was 28.21%, anti-CCP antibody positive RA patients was 32.2%, joint pain group was 38.89%, which were significantly higher. There was no statistical difference between other disease groups. The level of anti-CarP antibody was weakly correlated with level of rheumatoid factor (RF) and erythrocyte sedimentation rate (ESR) in RA patients, but it was moderately correlated with CRP and IgG level. Conclusion The protein chip chemiluminescence method for quantitative detection of anti-CarP antibody has good detection precision and wide linear range, and has good sensitivity and specificity. Anti-CarP antibody detection is valuable for RA diagnosis and disease activity evaluation.

Combined effects of octreotide and cisplatin on the proliferation of side population cells from anaplastic thyroid cancer cell lines.

Anaplastic thyroid cancer (ATC) represents the most aggressive subtype of thyroid cancer and has a poor prognosis. In addition to surgery, chemotherapy is an important treatment for ATC; however, the therapeutic effects of current chemotherapies for ATC are not particularly promising. There is a high proportion of side population (SP) cells in ATC, which may be a reason for its drug resistance. In the present study, the antitumor activities of combined octreotide (OCT) and cisplatin (DDP) on the proliferation and apoptosis of ATC SP cells were evaluated. First, SP cells from 8305C and BHT101 cell lines were detected and sorted. Following in vitro culture for 1 week, cluster of differentiation (CD)44, CD133, ATP-binding cassette (ABC) subfamily B member 1 (ABCB1), ABC subfamily G member 2 (ABCG2) and somatostatin receptor expression was detected to characterize the SP cells. An MTT assay was performed to investigate the combined effects on 8305C-SP cell proliferation in vitro, and a mouse model was used to investigate the combined effects on 8305C-SP cell proliferation in vivo. Annexin V/propidium iodide staining was used to investigate the combined effects on 8305C-SP cell apoptosis. Chemotherapeutic drug resistance-associated protein expression and apoptosis-associated protein expression were also detected following combined treatment. As a result, SP cells were identified in 8305C and BHT101 cells, and the proportion of 8305C-SP cells was increased compared with that of BTH101-SP cells. SP cells have enhanced proliferation, tumorigenicity and drug resistance compared with main population cells. The combined treatment of OCT with DDP suppressed the proliferation of 8305C-SP cells in vitro and in vivo, and induced 8305C-SP cell apoptosis. Combined treatment decreased the ABCB1 and ABCG2 expression by SP cells and activated mitochondrial apoptotic signaling, resulting in cell apoptosis. In conclusion, these data support the hypothesis that combined treatment with OCT and DDP induces ATC cell apoptosis and suppresses cell proliferation. These data provide a theoretical basis for further combined chemotherapy clinical applications.