Ki-67 Protein Levels Research Articles

Multi-institutional evaluation comparing guidance from International Ki67 Working Group vs National Health Commission of China on immunohistochemistry-based Ki67 assessment alongside the Quantitative Dot Blot method

PurposeRecommendations from the National Health Commission of China (NHCC) and the International Ki67 Working Group (IKWG) were issued to guide immunohistochemistry (IHC)-based Ki67 scoring for breast cancer patients in daily clinical practice. They were evaluated in this multi-institutional study alongside the results from the Quantitative Dot Blot (QDB) method.MethodsThree alternative adjacent sections from 40 primary ER+ breast cancer resection blocks were randomly assigned a number from 1 to 120 for Ki67 staining and reviewed by 21 pathologists, while the other three alternative sections were sent for QDB analysis of Ki67 protein levels. Ki67 scores were grouped by 5/30% (IKWG), 10/30% (NHCC) and 20/30% (NHCC appendix 9, NHCCa9), respectively while QDB results were grouped by C5–C95 of 2.31 nmol/g defined in previous study as low-, equivocal-, and high-risk groups.ResultsThe overall Intraclass Correlation Coefficient (ICC) was 0.785 for IHC evaluations from 21 pathologists, with Fleiss Kappa values of 0.555, 0.628, and 0.480 when Ki67 scores were grouped by guidance from IKWG, NHCC, and NHCCa9, respectively. In comparison, the ICC and Fleiss kappa values for the QDB analysis were 0.939 and 0.831, respectively. When IHC and QDB results were cross-referenced, more specimens were grouped as high-risk by QDB than IHC, and NHCCa9 led to the highest percentage of disagreement between the two methods.ConclusionThe IKWG recommendation was harder to achieve categorized agreement among pathologists than the NHCC recommendation, yet it led to the best agreement with the QDB to define the low-risk group. The QDB method offers significantly improved consistency compared to the current IHC-based Ki67 assessment.

Ki-67 and CDK1 control the dynamic association of nuclear lipids with mitotic chromosomes.

Nuclear lipids play roles in regulatory processes, such as signaling, transcriptional regulation, and DNA repair. In this report, we demonstrate that nuclear lipids may contribute to Ki-67-regulated chromosome integrity during mitosis. In COS-7cells, nuclear lipids are enriched at the perichromosomal layer and excluded from intrachromosomal regions during early mitosis but are then detected in intrachromosomal regions during late mitosis, as revealed by TT-ExM (expansion microscopy with trypsin digestion and tyramide signal amplification), an improved expansion microscopy technique that enables high-sensitivity and super-resolution imaging of proteins, lipids, and nuclear DNA. The nuclear nonhistone protein Ki-67 acts as a surfactant to form a repulsive molecular brush around fully condensed sister chromatids in early mitosis, preventing the diffusion or penetration of nuclear lipids into intrachromosomal regions. Ki-67 is phosphorylated during mitosis by cyclin-dependent kinase 1 (CDK1), the best-known master regulator of the cell cycle. Both Ki-67 knockdown and reduced Ki-67 phosphorylation by CDK1 inhibitors allow nuclear lipids to penetrate chromosomal regions. Thus, both Ki-67 protein level and phosphorylation status during mitosis appear to influence the perichromosomal distribution of nuclear lipids. Ki-67 knockdown and CDK1 inhibition also lead to uneven chromosome disjunction between daughter cells, highlighting the critical role of this regulatory mechanism in ensuring accurate chromosome segregation. Given that Ki-67 has been proposed to promote chromosome individualization and establish chromosome-cytoplasmic compartmentalization during open mitosis in vertebrates, our results reveal that nuclear lipid enrichment at the perichromosomal layer enhances the ability of Ki-67 to form a protective perichromosomal barrier (chromosome envelope), which is critical for correct chromosome segregation and maintenance of genome integrity during mitosis.

Investigation of the Effects of Silymarin on Ovarian Ischemia Reperfusion via Nrf-2/HO-1/NQO1, Ki-67 and Wnt Signaling Pathways.

Ovarian ischemia is a pathological condition that usually occurs due to ovarian torsion, resulting in the interruption of blood supply to the ovaries and oxygen deficiency. Silymarin (SLM) is a flavonoid complex of plant origin with pharmacological properties such as antioxidant, anti-inflammatory, and antiapoptotic effects. In this study, we investigated the effects of SLM through different pathways in rats subjected to experimental ovarian ischemia/reperfusion (I/R). Female Wistar rats were divided into five groups: Control, SLM (50 mg/kg), I/R, I/R + SLM25 (25 mg/kg), and I/R + SLM50 (50 mg/kg). SLM was given orally for 7 days, followed by ischemia (2 h) and reperfusion (2 h) on day 8. Biochemical (MDA, GSH, SOD, CAT, GPx) and histological (H&E, Ki-67 IHC) analyses were performed. Also, molecular (qRT-PCR) analyses were performed to evaluate oxidative stress, inflammation, apoptosis, and Wnt signaling. I/R increased MDA and NO levels in ovarian tissue while decreasing SOD, CAT, GPx, and GSH. Antioxidant defense genes (Nrf-2, HO-1, NQO1) were suppressed, and inflammation markers (NF-ĸB, IL-1β, TNF-α) along with apoptotic markers (Bax, Caspase-3) were elevated, while Bcl-2 decreased. The Wnt signaling pathway was inhibited, particularly at Wnt-3A, LRP5, Dvl-2, and Cyclin-1, reducing Ki-67 protein levels and IHC positivity. Silymarin has shown a therapeutic effect on ovarian ischemia reperfusion injury with its antioxidant, antiapoptotic and anti-inflammatory effects and cell cycle regulatory activity.

Xiyangshen Sanqi Danshen granules attenuated D-gal-induced C57BL/6J mouse aging through the AMPK/SIRT1 signaling pathway

BackgroundAging is a pressing global concern and is frequently accompanied by the emergence of many chronic diseases. Xiyangshen Sanqi Danshen granules (XSD) have antioxidant, anti-inflammatory and anti-fatigue functions, but the mechanism of their anti-aging effects is not clear. MethodsThis study elucidated the anti-aging mechanism and potentially active ingredients of XSD by performing transcriptomic analysis and network pharmacological analysis in a D-galactose (D-gal)-induced C57BL/6J mouse aging model. ResultsXSD improved learning and memory abilities while enhanced motor function in D-gal-induced aging mice, as shown by Morris water maze, passive avoidance test, and rotating rod test results. Additionally, XSD significantly increased the vascular pulse wave velocity (PWV), β-stiffness index and pressure strain elastic coefficient (EP), decreased carotid distensibility (CD) and decreased the expression levels of P53 and 8-OHdG in the common carotid arteries of D-gal mice. Transcriptome sequencing analysis identified that the AMPK/SIRT1 signaling pathway is the potential mechanism by which XSD attenuates aging. XSD also increased the protein levels of Ki67, AMPK, SIRT1 and the nuclear translocation of Nrf2 while decreased the protein levels of P21, P53, IL-18, 8-OHdG, nitrotyrosine, and COX-2 and the nuclear translocation of NF-κB p65 in the brains of D-gal-induced mice. The administration of the AMPK inhibitor and SIRT1 inhibitor hindered the anti-aging effect of XSD, as indicated by an elevation of 8-OHdG, COX-2, and nuclear translocation of NF-κB p65 ; and a decrease of Ki67 and the nuclear translocation of Nrf2. Network pharmacological analysis revealed that the potential active ingredients of XSD were quercetin, kaempferol, tanshinone IIA, isorhamnetin, ginsenoside F2, and cryptotanshinone. ConclusionCollectively, XSD mitigated D-gal-induced aging in C57BL/6J mice through enhancing the AMPK/SIRT1 signaling pathway. This research provides potential drugs for anti-aging and also promotes the usage of the anti-aging effect of XSD.

Effect of fermentation on the constituents in the branches and leaves of Taxus media and non-small cell lung cancer.

Non-small cell lung cancer (NSCLC) is a prominent lung cancer disease worldwide. Currently, commonly used methods, such as surgery and radiotherapy, have significant side effects. Traditional Chinese medicine (TCM) has become a research hotspot because of its safe and effective characteristics. The branches and leaves of Taxus media are abundant in antitumor active compounds, and there has been no research conducted as yet regarding its anti-lung cancer molecular mechanism. The aim of this study is to investigate the antitumor activity of two samples before and after fermentation of T. media, and to research the molecular mechanism of its inhibitory effect on NSCLC. The chemical composition of pre-fermentation T. media (TM) and post-fermentation T. media qu (TMQ) were investigated using UHPLC-Q-Qrbitrap HRMS and high-performance liquid chromatography (HPLC). The anti-lung cancer activities of TM and TMQ were compared using an A549-induced tumor mouse model. An enzyme-linked immunosorbent assay (ELISA), hematoxylin and eosin (H&E) staining, immunohistochemistry, and immunofluorescence were used to determine the of TMQ mechanism of action. The results indicated that TM and TMQ contained 83 compounds, consisting primarily of flavonoids, organic acids, and taxanes. Both taxanes and flavonoids in TMQ were higher than that in TM. Both TM and TMQ effectively inhibited the tumor growth in non-small cell lung cancer (NSCLC), and the inhibition rate was greater in TMQ (57.24%) than in TM (49.62%). TMQ administration downregulated the tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and the glutathione (GSH) level and upregulated interferon-γ (IFN-γ), reactive oxygen species (ROS), and malondialdehyde (MDA) levels in the serum of tumor mice. TMQ treatment also increased the protein expression of Bax, Caspase-3, and Beclin-1 in tumor tissues. In contrast, the bcl-2, PI3K, Ki67, ULK1, and mTOR protein levels were suppressed by TMQ. Protein assay analyses reemphasized the superior antitumor effect of TMQ over TM. These cumulative findings demonstrated that the mechanism of action of TMQ was closely related to the activation of transcriptional misregulation in the cancer pathway that inhibited the cholinergic synaptic, AMPK, and PI3K/Akt/mTOR signaling pathways. This study demonstrated that fermentation increased the active ingredient contents and antitumor effects of T. media. In addition, post-fermentation TMQ was superior to TM as a herbal medicine for NSCLC treatment.

Syndecan-4 inhibition attenuates cartilage degeneration in temporomandibular joint osteoarthritis.

Syndecan 4 (SDC4), a type I transmembrane proteoglycan, serves as a critical link between chondrocytes and the extracellular matrix. This study aimed to explore the role of SDC4 in cartilage degeneration of temporomandibular joint osteoathritis (TMJOA). Condylar chondrocytes were stimulated with varying concentrations of recombinant rat interleukin-1β (rrIL-1β) and SDC4 small interfering RNA (si-SDC4). Anti-SDC4 ectodomain-specific antibodies or IgG were intra-articularly administrated in a TMJOA model rats. SDC4 conditional knockout (SDC4-cKO) and Sdc4flox/flox mice were induced TMJOA. Cartilage degeneration was assessed using haematoxylin & eosin (H&E) and safranin O (SO) staining. Protein levels of SDC4, matrix metalloproteinases (MMPs), a disintegrin and metalloproteinase with a thrombospondin motifs 5 (ADAMTS5), tumour necrosis factor α (TNFα), type II collagen (Col-II), aggrecan (ACAN), cleaved caspase 3 (CASP3), Ki67 and related pathways in condylar cartilage were evaluated by immunohistochemical (IHC) staining or western blot assays. SDC4 expression was evidently increased in MIA-model animals compared to control groups. rrIL-1β stimulation increased the expression of SDC4, MMP3 and ADAMTS5 expression in chondrocytes, while decreasing the expression of Col-II. These effects were reversed by si-SDC4 invitro. Invivo, SDC4 blockade reduced the death of chondrocytes and the loss of cartilage matrix, which was evidenced by increased expression of Col-II and ACAN, and a decrease in SDC4, MMP13 and cleaved-CASP3-positive cells. Furthermore, the protein levels of ACAN and Ki67 were elevated, and the ERK1/2 and P38 signalling pathways were activated following SDC4 inhibition. SDC4 inhibition significantly ameliorates condylar cartilage degeneration, which was mediated, at least partly, through P38 and ERK1/2 signalling. Inhibition of SDC4 may be of great value for the treatment of TMJOA.

Elastin-derived peptides (EDPs) affect gene and protein expression in human mesenchymal stem cells (hMSCs) – preliminary study

During the aging process, elastin is degraded and the level of elastin-derived peptides (EDPs) successively increases. The main peptide released from elastin during its degradation is a peptide with the VGVAPG sequence. To date, several papers have described that EDPs or elastin-like peptides (ELPs) affect human mesenchymal stem cells (hMSCs) derived from different tissues. Unfortunately, despite the described effect of EDPs or ELPs on the hMSC differentiation process, the mechanism of action of these peptides has not been elucidated. Therefore, the aim of the present study was to evaluate the impact of the VGVAPG and VVGPGA peptides on the hMSC stemness marker and elucidation of the mechanism of action of these peptides. Our data show that both studied peptides (VGVAPG and VVGPGA) act with the involvement of ERK1/2 and c-SRC kinases. However, their mechanism of activation is probably different in hMSCs derived from adipose tissue. Both studied peptides increase the KI67 protein level in hMSCs, but this is not accompanied with cell proliferation. Moreover, the changes in the NANOG and c-MYC protein expression and in the SOX2 and POU5F1 mRNA expression suggest that EDPs reduced the hMSC stemness properties and could initiate cell differentiation. The initiation of differentiation was evidenced by changes in the expression of AhR and PPARγ protein as well as specific genes (ACTB, TUBB3) and proteins (β-actin, RhoA) involved in cytoskeleton remodeling. Our data suggest that the presence of EDPs in tissue can initiate hMSC differentiation into more tissue-specific cells.

Targeting next-generation PDE4 inhibitors in search of potential management of rheumatoid arthritis and psoriasis

Immune-mediated inflammatory diseases (IMIDs) comprise a broad spectrum of conditions characterized by systemic inflammation affecting various organs and tissues, for which there is no known cure. The isoform-specific inhibition of phosphodiesterase-4B (PDE4B) over PDE4D constitutes an effective therapeutic strategy for the treatment of IMIDs that minimizes the adverse effects associated with non-selective PDE4 inhibitors. Thus, we report a new class of isoquinolone derivatives as next-generation PDE4 inhibitors for effective management of rheumatoid arthritis (RA) and psoriasis. Among the series, 8 compounds i.e. 1e, 1l, 1m, 1n, 1o, 2m, 2o and 3o showed promising PDE4B inhibition (>80 %) in vitro with IC50 ∼ 1.4–6.2 µM. The compound 1l was identified as an initial hit and was pursued for further studies. According to structure–activity relationship (SAR), an allyl group at C-4 position improved PDE4B inhibition. The correlation between in vitro activity data and binding affinities obtained via molecular docking suggested that the high-affinity binding to PDE4B is a prerequisite for the effective inhibition of PDE4B. Notably, the hit 1l showed selectivity towards PDE4B over PDE4D in vitro. Furthermore, 1l treatment (30 mg/kg) in the adjuvant-induced arthritis (AIA) rat model induced by complete Freund’s adjuvant (CFA) demonstrated anti-arthritic potential via ameliorating paw swelling and body weight, narrowing joint space, reducing excessive immune cells infiltration and pannus formation in addition to reducing mRNA expression of pro-inflammatory cytokines such as TNF-α and IL-6 in synovial tissues of experimental rats. Additionally, 1l reduced the hyper-proliferative state and colony forming potential of IMQ-induced psoriatic keratinocytes. The treatment of these cells with 1l markedly reduced the protein levels of Ki67 and mRNA levels of pro-inflammatory cytokines e.g. IL-17A and TNF-α suggesting its potent anti-psoriatic potential. Furthermore, 1l did not show any significant adverse effects when evaluated in a systematic toxicity (e.g. teratogenicity, hepatotoxicity and cardiotoxicity) studies in zebrafish at the tested concentrations (1–100 µM) and the NOAEL (no-observed-adverse-effect level) was found to be 100 µM. Thus, with promising anti-inflammatory effects both in vitro and in vivo along with PDE4B selectivity with an acceptable safety margin, 1l emerged as a new and promising inhibitor for further studies.

Molecular Mechanism of circVRK1 Regulating the Proliferation and Apoptosis of Acute Lymphoblastic Leukemia KOCL44 Cells by Targeting miR-4428

To elucidate the role of circVRK1 and its interaction with miR-4428 in regulating proliferation and apoptosis in acute lymphoblastic leukemia (ALL) cells. KOCL44 ALL cells were cultured in vitro, and experimental groups included pcDNA, pcDNA-circVRK1, anti-miR-NC, anti-miR-4428, si-NC, si-circVRK1, pcDNA-circVRK1+miR-NC, and pcDNA-circVRK1+miR-4428. The expression levels of circVRK1 and miR-4428 were detected using qRT-PCR. CCK-8 assays and flow cytometry were used to assess cell proliferation and apoptosis, respectively. The dual luciferase reporter assays were employed to investigate the interaction between circVRK1 and miR-4428, with groups categorized as WT-circVRK1+miR-NC, WT-circVRK1+miR-4428, MUT-circVRK1+miR-NC, and MUT-circVRK1+ miR-4428. Western blotting was utilized to detect the expression levels of Ki-67, cleaved caspase-3, and cleaved caspase-9 proteins. Compared to the pcDNA group, circVRK1 expression was up-regulated in the pcDNA-circVRK1 group (P<0.05). Compared to transfection with pcDNA or anti-miR-NC, transfection with pcDNA-circVRK1 or anti-miR-4428 led to decreased cell viability and Ki-67 protein levels in KOCL44 cells (P<0.05), and increased apoptosis rates and levels of cleaved caspase-3 and cleaved caspase-9 (P<0.05). circVRK1 was found to negatively regulate miR-4428 expression, with this effect observed only in the WT-circVRK1 group. miR-4428 levels were lower in the pcDNA-circVRK1 group compared to the pcDNA group (P<0.05) and higher in the si-circVRK1 group compared to the si-NC group (P<0.05). Co-transfection with pcDNA-circVRK1+miR-4428 resulted in increased cell viability (P<0.05) and Ki-67 expression (P<0.05), and decreased apoptosis rates and levels of cleaved caspase-3 and cleaved caspase-9 (P<0.05) compared to co-transfection with pcDNA-circVRK1+miR-NC. Overexpression of circVRK1 reduces the proliferation ability of acute ALL cells and induces cell apoptosis by downregulating miR-4428 expression.

LncRNA SH3PXD2A-AS1 facilitates cisplatin resistance in non-small cell lung cancer by regulating FOXM1 succinylation

BackgroundLong noncoding RNAs (lncRNAs) play vital regulatory functions in non-small cell lung cancer (NSCLC). Cisplatin (DDP) resistance has significantly decreased the effectiveness of DDP-based chemotherapy in NSCLC patients. This study aimed to investigate the effects of SH3PXD2A antisense RNA 1 (SH3PXD2A-AS1) on DDP resistance in NSCLC.MethodsProliferation and apoptosis of DDP-resistant NSCLC cells were detected using cell counting kit-8 and flow cytometry assays. The interaction between SH3PXD2A-AS1 and sirtuin 7 (SIRT7) was assessed using co-immunoprecipitation (Co-IP), RNA pull-down, RNA immunoprecipitation (RIP), RNA fluorescence in situ hybridization, and immunofluorescence assays, while succinylation (SUCC) of Forkhead Box M1 (FOXM1) was analyzed by IP and Western blot assays. The role of SH3PXD2A-AS1 in vivo was explored using a xenografted tumor model.ResultsExpression of SH3PXD2A-AS1 was found elevated in DDP-resistant NSCLC cells, while it’s knocking down translated into suppression of cell viability and promotion of apoptosis. Moreover, silencing of SH3PXD2A-AS1 resulted in decreased FOXM1 protein level and enhanced FOXM1-SUCC protein level. The SIRT7 was found to interact with FOXM1, translating into inhibition of FOXM1 SUCC at the K259 site in human embryonic kidney (HEK)-293T cells. Overexpressing of SIRT7 reversed the increase of FOXM1-SUCC protein level and apoptosis, and the decrease of cell viability induced by silencing of SH3PXD2A-AS1. In tumor-bearing mice, SH3PXD2A-AS1 inhibition suppressed tumor growth and the protein levels of Ki67, SIRT7, and FOXM1.ConclusionSH3PXD2A-AS1 promoted DDP resistance in NSCLC cells by regulating FOXM1 SUCC via SIRT7, offering a promising therapeutic approach for NSCLC.

LncRNA KTN1-AS1 Drives Tumor Progression in Non-Small Cell Lung Cancer through microRNA-153-3p/KLF5 Axis

IntroductionThe most typical kind of lung cancer is non-small cell lung cancer (NSCLC). Surgery, targeted therapy, chemotherapy, and immunotherapy are all options for the treatment of NSCLC. LncRNA KTN1-AS1 is significantly increased in NSCLC, and it modulates the expression of microRNAs and downstream genes, promoting NSCLC progression.Material and methodsTCGA was employed to predict lncRNA KTN1-AS1 expression in NSCLC. The starBase was utilized to predict downstream microRNAs of KTN1-AS1. The RNA22 database was employed to predict corresponding binding sites. Subcellular localization of KTN1-AS1 was forecasted using the lncLocator database, and the results were validated by FISH. qRT-PCR was used to test KTN1-AS1, microRNA-153-3p, and KLF5 expression. CCK-8, flow cytometry, and Transwell were used to determine cell viability, proliferation, migration, and invasion. Western blot was used to test KLF5 and Ki67 protein levels, and dual-luciferase assay was used to assess bindings of KTN1-AS1 with microRNA-153-3p, and KLF5 with microRNA-153-3p.ResultsKTN1-AS1 was significantly upregulated in NSCLC cells. Silencing KTN1-AS1 significantly repressed the proliferation, migration, and invasion of NSCLC cells. KTN1-AS1 bound to microRNA-153-3p, and KLF5 was a direct target of microRNA-153-3p. Inhibition of microRNA-153-3p or overexpression of KLF5 restored the stimulatory impact of KTN1-AS1 knockdown on NSCLC cell proliferation and migration.ConclusionsKTN1-AS1 drove proliferation, migration, and invasion of NSCLC cells by regulating microRNA-153-3p/KLF5 axis. By studying the role of the KTN1-AS1/microRNA-153-3p/KLF5 axis in NSCLC, the possibility of targeting this axis as a therapeutic target in NSCLC can be explored.

The fusion gene LRP1–SNRNP25 drives invasion and migration by activating the pJNK/37LRP/MMP2 signaling pathway in osteosarcoma

Through transcriptome sequencing, we previously identified a new osteosarcoma-specific, frequent fusion gene, LRP1–SNRNP25, and found that it played an important role in tumor cell invasion and migration. However, the specific mechanism remains unclear. In this article, whole-genome sequencing further confirmed that the LRP1–SNRNP25 fusion gene is formed by fusion of LRP1 exon 8 and SNRNP25 exon 2. In vitro, scratch and Transwell assays demonstrated that the migration and invasion abilities of LRP1–SNRNP25-overexpressing osteosarcoma cells were significantly increased. To explore the molecular mechanism of the LRP1–SNRNP25 fusion in affecting osteosarcoma cell migration and invasion, we evaluated the migration and invasion-related molecular signaling pathways by western blotting. Some migration- and invasion-related genes, including pJNK and MMP2, were upregulated. Coimmunoprecipitation–mass spectrometry showed that 37LRP can interact with pJNK. Western blotting confirmed that LRP1–SNRNP25 overexpression upregulates 37LRP protein expression. Immunofluorescence staining showed the intracellular colocalization of LRP1–SNRNP25 with pJNK and 37LRP proteins and that LRP1–SNRNP25 expression increased the pJNK and 37LRP levels. Coimmunoprecipitation (co-IP) confirmed that LRP1–SNRNP25 interacted with pJNK and 37LRP proteins. The pJNK inhibitor SP600125 dose-dependently decreased the pJNK/37LRP/MMP2 levels. After siRNA-mediated 37LRP knockdown, the MMP2 protein level decreased. These two experiments proved the upstream/downstream relationship among pJNK, 37LRP, and MMP2, with pJNK the farthest upstream and MMP2 the farthest downstream. These results proved that the LRP1–SNRNP25 fusion gene exerts biological effects through the pJNK/37LRP/MMP2 signaling pathway. In vivo, LRP1–SNRNP25 promoted osteosarcoma cell growth. Tumor growth was significantly inhibited after SP600125 treatment. Immunohistochemical analysis showed that the pJNK, MMP2, and Ki-67 protein levels were significantly increased in tumor tissues of LRP1–SNRNP25-overexpressing cell-injected nude mice. Furthermore, lung and liver metastasis were more prevalent in these mice. In a word, LRP1–SNRNP25 promotes invasion, migration, and metastasis via pJNK/37LRP/MMP2 pathway. LRP1–SNRNP25 is a potential therapeutic target for LRP1–SNRNP25-positive osteosarcoma.

High copper levels induce premature senescence in 3T3-L1 preadipocytes

Copper (Cu) dyshomeostasis has been linked to obesity and related morbidities and also to aging. Cu levels are higher in older or obese individuals, and adipose tissue (AT) Cu levels correlate with body mass index. Aging and obesity induce similar AT functional and structural changes, including an accumulation of senescent cells. To study the effect of Cu-mediated stress-induced premature senescent (Cu-SIPS) on preadipocytes, 3T3-L1 cell line was exposed to a subcytotoxic concentration of copper sulfate. After Cu treatment, preadipocytes acquired typical senescence characteristics including diminished cell proliferation, cell and nuclei enlargement and increased lysosomal mass (higher Lamp2 expression and a slight increased number of cells positive for β-galactosidase associated with senescence (SA-β-Gal)). Cell cycle arrest was due to upregulation of p16Ink4aInk4a and p21Waf1/Cip1. Accordingly, protein levels of the proliferation marker KI67 were reduced. Cu-SIPS relates with oxidative stress and, in this context, an increase of SOD1 and HO-1 expression was detected in Cu-treated cells. The mRNA expression of senescence-associated secretory phenotype factors, such as Mmp3, Il-6 and Tnf-α, increased in Cu-SIPS 3T3-L1 cells but no effect was observed on the expression of heterochromatin-associated protein 1(HP1).Although the downregulation of Lamin B1 expression is considered a hallmark of senescence, Cu-SIPS cells presented higher levels of Lamin B1. The dysregulation of nuclear lamina was accompanied by an increase of nuclear blebbing, but not of micronuclei number.To conclude, a Cu-SIPS model in 3T3-L1 preadipocytes is here described, which may be an asset to the study of AT dysregulation observed in obesity and aging.

UBE2C promotes the proliferation of acute myeloid leukemia cells through PI3K/AKT activation

This study aims to investigate the role and mechanism of tubiquitin-conjugating enzyme E2 C (UBE2C) in acute myeloid leukemia (AML). Initially, UBE2C expression in leukemia was analyzed using the Cancer Genome Atlas database. Further, we silenced UBE2C expression using small-hairpin RNA (sh-RNA). UBE2C expression was detected via the quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) and Western blot analysis. Apoptotic events and reactive oxygen species (ROS) levels were detected by flow cytometry. A xenograft model of leukemia cells were established, and the protein levels of UBE2C, KI-67, and cleaved-caspase 3 were detected by immunohistochemistry. We reported an overexpression of UBE2C in leukemia patients and cell lines (HL60, THP-1, U937, and KG-1 cells). Moreover, a high expression level of UBE2C was correlated with a dismal prognosis in AML patients. UBE2C knockdown inhibited the viability and promoted apoptosis in AML cells by regulating the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) signaling pathway. Furthermore, UBE2C knockdown increased cellular Fe2+ and ROS levels, and enhanced erastin-induced ferroptosis in a proteasome-dependent manner. UBE2C knockdown also suppressed the tumor formation of AML cells in the mouse model. In summary, our findings suggest that UBE2C overexpression promotes the proliferation and inhibits ferroptosis in AML cells by activating the PI3K/AKT pathway.

Abstract 1510: Cell-cell contacts regulate HER2 cellular localization and the transitions between migration and proliferation in breast cancer cells

Abstract Introduction: Epithelial-to-mesenchymal transition (EMT) is widely recognized as the primary mechanism regulating invasion and metastatic dissemination in carcinomas. In contrast, the mechanisms triggering single disseminated cancer cells (DCC) to reacquire their epithelial identity at ectopic sites, initiating metastasis formation, remain unclear. Since we had previously noted that HER2 expression levels and cellular density impact on migration and proliferation, we sought to determine whether they are involved in molecular mechanisms regulating transitions between proliferation and migration. Methods: To control HER2 expression levels we generated inducible cell models. Cell density was assessed by the number of cell-cell contacts or by the number of cells per area. Pathway analyses were performed by gene expression analysis, protein interactions by western blotting and mass spectrometry. Migration and proliferation were analyzed by functional assays including in vitro live cell imaging. Results: Migrating epithelial cells undergo reduced protein trafficking, resulting in a perinuclear deposition of HER2. This was accompanied by increased calcium ion regulation via phospholipase-C in the endoplasmic reticulum (ER). Upon the establishment of cell-cell contacts, particularly between cells expressing desmosome cadherin proteins, HER2 is redirected to the cell surface through direct physical binding with desmoplakin, facilitating proliferation signals. Then, PIP2 to PIP3 is converted through the activation of the PI3K pathway, concomitant with the upregulation of PDPK1. The PH domain of PDPK1 exhibits a high binding affinity to PIP2 molecules. Consequently, membrane localization of HER2 significantly diminishes PIP2 availability for the PLC pathway, redirecting cells towards proliferation. Patient sample analysis confirmed the loss of membrane-bound HER2 in solitary circulating tumor cells (CTCs), which was paralleled by increased plakoglobin, elevated ZEB1, and reduced KI67 protein levels. Conclusion: Cell-cell contacts determine the cellular localization and function of growth factor receptors like HER2. Single disseminating cancer cells therefore need to establish such contacts at metastatic sites to activate proliferation programs. Our data are in line with findings that circulating tumor cell clusters are associated with higher metastatic rates, the impact of specific metastatic niches for outgrowth and have implementation for the targeting of single DCC. Citation Format: Hedayatollah Hosseini, Saba Sameri, Shabnam Shahrivari, Carolina Fisch, Miriam Kokal, Michael Schletter, Paul Sylvester Hahn, Lisa Seider, Marisa Schübel, Durdam Das, Martin Hoffmann, Christian Werno, Kathrin Weidele, Vladan Milosevic, Arne Östman, Shamim Sarhadi, Joachim Wegener, Stefanie Michaelis, Florian Weber, Astrid Bruckmann, Ernst R. Tamm, Yuting Li, Christoph A. Klein. Cell-cell contacts regulate HER2 cellular localization and the transitions between migration and proliferation in breast cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1510.

Inhibition of p38 MAPK/NF-κB p65 signaling pathway activity by rare ginsenosides ameliorates cyclophosphamide-induced premature ovarian failure and KGN cell injury

Ethnopharmacological relevancePanax ginseng C. A. Mey., one of the most used herbs in the world, shows effective treatment in reproductive injury. Recent studies have proven that the processed product, red ginseng, which is more active than ginseng itself. Therefore, it is speculated that its main functional component, rare ginsenosides (heat-transformed saponin, HTS), may be effective in treating premature ovarian failure (POF), but its efficacy has not yet been experimentally confirmed. Aim of the studyTo evaluate whether HTS could attenuate cyclophosphamide-induced inflammation and oxidative damage in POF model rats and the human granulosa-like KGN cell line and protect granulosa cell proliferation. Material and methodsHTS were isolated from ginsenosides and high performance liquid chromatography (HPLC) analysis was used to analyze the HTS components. Cyclophosphamide (CP) was used to establish a POF rat model and KGN cell injury model. Reactive oxygen species (ROS) and antioxidant enzyme production was determined using specific assays, while inflammatory cytokine secretion was measured by enzyme-linked immunosorbent assay (ELISA). The proliferative function of granulosa cells was assessed using high-content screening and immunohistochemistry to determine the Ki67 protein level. Protein expression in ovarian tissues and KGN cells was analyzed by Western blotting, quantitative real-time PCR (qRT-PCR) was used to determine the transcriptional changes in ovarian tissues and KGN cells. ResultsIn CP-treated POF model rats, HTS significantly decreased malondialdehyde (MDA), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) levels, increased glutathione oxidase (GSH) levels, and upregulated Ki67 expression in ovarian granulosa cells. In addition, HTS significantly increased cell survival and Ki67 expression levels in CP-treated cells, and superoxide dismutase (SOD) levels were significantly increased. HTS significantly downregulated IL-6, TNF-α, and interleukin-1β (IL-1β) mRNA expression and significantly inhibited nuclear factor kappa-B p65 (NF-κB p65) and p38 mitogen activated protein kinase (p38 MAPK) phosphorylation in POF model rats and KGN cells. Moreover, NF-κB p65 and p38 MAPK levels were significantly increased in ovarian granulosa cells. p65 and p38 protein and gene expression was significantly downregulated. ConclusionHTS ameliorated CP-induced POF and human granulosa cell injury, possibly by inhibiting inflammation and oxidative damage mediated by the p38 MAPK/NF-κB p65 signaling pathway.

Effects of metronidazole on colorectal cancer occurrence and colorectal cancer liver metastases by regulating Fusobacterium nucleatum in mice.

Colorectal cancer (CRC) represents a leading cause of cancer-related deaths. Metronidazole (MNZ) is exceedingly implicated in CRC. This study explored the roles of MNZ in mouse CRC occurrence and liver metastasis (CRLM). Male BALB/c nude mice were subjected to CRC and CRLM modeling, orally administration with MNZ (1 g/L) 1 week before modeling, and disease activity index (DAI) evaluation. Fresh stool and anal swab samples were collected on the morning of the 28th day after modeling. The relative expression of Fusobacterium nucleatum (F. nucleatum) DNA was assessed by quantitative polymerase chain reaction. After euthanasia, tumor tissues and liver tissues were separated and the tumor volume and weight change were measured. The liver tissues were stained with hematoxylin-eosin to quantitatively analyze the metastatic liver nodules. Malignant tumor biomarker Ki67 protein levels in liver tissues/DNA from stool samples were detected by immunohistochemistry/high-throughput 16S rRNA gene sequencing. Bioinformatics analysis was performed on the raw sequence data to analyze microbial community richness (Chao1 index, ACE index) and microbial community diversity (Shannon index). The DAI and F. nucleatum DNA relative expression in feces and anal swabs of the CRC and CRLM groups were raised and repressed after MNZ intervention. MNZ repressed tumor occurrence and growth in mice to a certain extent, alleviated CRLM malignant degree (reduced liver metastases and Ki67-positive cell density/number), and suppressed CRC liver metastasis by regulating intestinal flora structure, which affected the intestinal characteristic flora of CRC and CRLM mice. MNZ suppressed CRC occurrence and CRLM in mice by regulating intestinal F. nucleatum.

HIF-1α regulates the cell viability in radioiodine-resistant papillary thyroid carcinoma cells induced by hypoxia through PKM2/NF-κB signaling pathway.

The curative treatment options for papillary thyroid cancer (PTC) encompass surgical intervention, radioactive iodine administration, and chemotherapy. However, the challenges of radioiodine (RAI) resistance, metastasis, and chemotherapy resistance remain inadequately addressed. The objective of this study was to investigate the protective role of hypoxia-inducible factor-1α (HIF-1α) in 131 I-resistant cells and a xenograft model under hypoxic conditions, as well as to explore potential mechanisms. The effects of HIF-1α on 131 I-resistant BCPAP and TPC-1 cells, as well as the xenograft model, were assessed in this study. Cell viability, migration, invasion, and apoptosis rates were measured using Cell Counting Kit-8, wound-healing, Transwell, and flow cytometry assays. Additionally, the expressions of Ki67, matrix metalloproteinase-9 (MMP-9), and pyruvate kinase M2 (PKM2) were examined using immunofluorescence or immunohistochemistry assays. Sodium iodide symporter and PKM2/NF-κBp65 relative protein levels were detected by western blot analysis. The findings of our study indicate that siHIF-1α effectively inhibits cell proliferation, cell migration, and invasion in 131 I-resistant cells under hypoxic conditions. Additionally, the treatment of siHIF-1α leads to alterations in the relative protein levels of Ki67, MMP-9, PKM2, and PKM2/NF-κBp65, both in vivo and in vitro. Notably, the effects of siHIF-1α are modified when DASA-58, an activator of PKM2, is administered. These results collectively demonstrate that siHIF-1α reduces cell viability in PTC cells and rat models, while also mediating the nuclear factor-κB (NF-κB)/PKM2 signaling pathway. Our findings provide a new rationale for further academic and clinical research on RAI-resistant PTC.

Circulating miR-221/222 expression as microRNA biomarker predicting tamoxifen treatment outcome: a case-control study.

This case-control research included individuals with the luminal subtype of BC who had received tamoxifen medication for around one year. Furthermore, the case group contained 15 individuals with local recurrence or metastases, while the control group comprised 19 patients without local recurrence or metastases. Plasma miR-221/222 quantification was performed with real-time PCR using transcript-specific primers. A significant difference was found in circulating miR-221 expression between cases and controls (P=0.005) but not in miR-222 expression (P=0.070). There were no significant differences between miR-221/222 expression, progesterone receptor, Ki67 protein levels, lymphovascular invasion, and stage. However, receiver operator characteristic curve analyses showed miR-221/222 expressions predictive of tamoxifen resistance (P=0.030) with a sensitivity of 60.00 and a specificity of 83.33%. The use of circulating miR-221/222 expression can predict relapse as well as resistance to tamoxifen treatment in BC patients, and their testing is recommended for luminal subtype BC patients who will undergo tamoxifen therapy to determine their risk of tamoxifen resistance early, increasing treatment effectiveness.

Effect of LINC00174 on the Malignant Proliferation of Multiple Myeloma Cells and Its Related Mechanism

To explore the biological function of LINC00174 in multiple myeloma (MM). Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the expressions of LINC00174 and miR-150 in peripheral blood of MM patients and MM cell lines. EdU staining and flow cytometry were used to detect the effects of LINC00174 and miR-150 on the proliferation and apoptosis of MM cells. Western blot was used to detect the expressions of proliferation marker nuclear-related antigen Ki67, apoptosis-related protein cleaved caspase-3 and transcription factor forkhead box protein P1 (FOXP1). Bioinformatics and dual-luciferase reporter assay were used to verify the targeting relationship between LINC00174 and miR-150 and the targeting relationship between miR-150 and FOXP1. The level of LINC00174 was significantly increased in peripheral blood of MM patients and MM cell lines (P <0.05). Compared with NC-siRNA group, the expression of LINC00174 was significantly reduced in LINC00174-siRNA group, the proliferation of U266 cells was reduced, the apoptosis rate was significantly increased, the level of Ki67 protein was reduced, and the level of cleaved caspase-3 protein was increased (all P <0.05). LINC00174 targeted regulation of the expression of miR-150. Compared with LINC00174-siRNA+NC inhibitor group, the expression of miR-150 in U266 cells in LINC00174-siRNA+miR-150 inhibitor group was significantly reduced, the cell proliferation was enhanced, the apoptosis rate was reduced, the level of Ki67 protein was increased, and the level of cleaved caspase-3 was decreased (all P <0.05). FOXP1 is the target gene of miR-150. Compared with NC mimic group, the expression of FOXP1 protein in miR-150 mimic group was significantly reduced, the cell proliferation was reduced, the apoptosis rate was significantly increased, Ki67 protein level was decreased, and the level of cleaved caspase-3 was increased. Compared with miR-150 mimic + vector group, the expression of FOXP1 protein in miR-150 mimic + pcDNA-FOXP1 group was significantly increased, the cell proliferation was enhanced, the apoptosis rate was reduced, the level of Ki67 protein was increased, and the level of cleaved caspase-3 was decreased (all P <0.05). LINC00174 promotes the proliferation of MM cells and inhibits cell apoptosis by regulating the miR-150/ FOXP1 axis.