Proliferating Cell Nuclear Antigen Expression Research Articles

Anti-proliferative and anti-inflammatory effects of the application of baclofen cream, a GABAB receptor agonist, on skin inflammation in mice

Previous studies have demonstrated the role of γ-aminobutyric acid type B (GABAB) receptors in skin-related conditions and pain. However, most studies have focused on the main effects of GABAB on the central nervous system. Therefore, this study has aimed to determine the potential topical anti-inflammatory and anti-proliferative effects of baclofen cream in an inflammatory skin disease model. The effects of the baclofen cream were evaluated using acute and chronic models of 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced skin inflammation in mouse ears. Histological and immunohistochemical evaluations were performed using an ear oedema assay. The effect of baclofen on keratinocyte proliferation was assessed in PAM212, the murine keratinocyte cell line. The results demonstrate that a single topical application of 5% baclofen, 7.5% baclofen, and 1% dexamethasone each inhibited acute TPA-induced ear oedema (58.94 ± 6.14%, 47.73 ± 11.26%, and 87.33 ± 4.59%, respectively). These results were confirmed by histological analysis. In the chronic model, baclofen (5%) and dexamethasone (1%) each inhibited ear oedema and the maximum inhibitory effect was reached at the end of the experiment (9th day of TPA application) with a percentage inhibition of 54.60 ± 6.15% for baclofen and 71.68 ± 3.45% for dexamethasone, when compared to the vehicle. These results were confirmed by histological analysis. Baclofen and dexamethasone also reduced proliferating cell nuclear antigen expression by 62.01 ± 6.65% and 70.42 ± 6.11%, respectively. However, baclofen did not inhibit keratinocyte proliferation in PAM212 cells. In conclusion, these results demonstrate that baclofen exhibits notable topical antiproliferative and anti-inflammatory properties and could be a potential therapeutic alternative for treating inflammatory and proliferative skin diseases.

Forkhead Box P4 promotes the proliferation of cells in colorectal adenocarcinoma

Abstract Objectives Forkhead Box P4 (FOXP4) is a transcription factor that promotes tumor formation and progression. However, studies on its roles in colorectal adenocarcinoma (CRAC) and cell proliferation regulation are few to date. This work investigates the expression of FOXP4 in CRAC, explores the characteristic of FOXP4 in different clinicopathological features, and analyzes its regulation of cell proliferation. Methods The GEPIA database was used to predict the trend of FOXP4 expression in colon cancer and normal mucosa. Tumor tissue and normal paracancerous mucosal tissue were sampled from 64 cases diagnosed with CRAC and who were receiving radical surgery at Tianjin Hospital from January 2017 and December 2022. FOXP4 and proliferating cell nuclear antigen (PCNA) were detected by the immunohistochemistry EnVision method. The colon cancer cell lines SW480, HCT15, and SW620 and the normal colon cell line NCM460 were selected, and expression of FOXP4 was detected by the Western blot method. The siRNA-FOXP4 plasmid was synthesized and transfected with SW480 and HCT15 cell lines, respectively, to establish si-FOXP4 groups, and empty vector transfection group (NC-FOXP4) and blank control group (NC) was set up. The expression levels of FOXP4 and PCNA were detected by the Western blot method, while the cell proliferation activity was assessed using CCK-8. Normally distributed quantitative data were compared between two and more groups with ANOVA (SNK-based pairwise comparison), while intergroup enumeration data comparisons were performed through χ 2 test and assessed through linear correlation analysis. Results GEPIA-based prediction shows a potential rise in FOXP4 expression in colon cancer. The rate of positive FOXP4 expression is significantly higher in CRAC tissue than in normal mucosa (p<0.05). The difference in FOXP4 is statistically significant in the comparison of maximum tumor diameter and depth of invasion in CRAC (p<0.05) but not in the comparison of gender, age, degree of differentiation, tumor focus, tumor embolism, and lymph node metastasis (p>0.05). The expression levels of FOXP4 and PCNA in CRAC are positively correlated (p<0.05). FOXP4 expression is significantly higher in cell lines SW480, HCT15, and SW620 than in cell line NCM460. The cell proliferation activity and PCNA expression are significantly lower in si-FOXP4 group than in NC-FOXP4 and NC groups for cell lines SW480 and HCT15. Conclusions FOXP4 is highly expressed and has a proliferative effect on tumor cells in CRAC.

Protective effect of thymol on glycerol-induced acute kidney injury

Acute kidney injury (AKI) is a syndrome characterized by an accelerating decrease in renal function in a short time. Thymol is one of the main components of thyme species and has a variety of pharmacological effects. Here, we investigated whether thymol could ameliorate rhabdomyolysis (RM)-induced AKI and its related mechanism. Glycerol was used to induce RM-associated AKI in rats. Rats received thymol (20 mg/kg/day or 40 mg/kg/day) gavage 24 h before glycerol injection until 72 h after injection daily. Kidney injury was identified by measuring serum creatinine (Scr) and urea levels and by H&E and PAS staining and immunohistochemistry (the expression of proliferating cell nuclear antigen (PCNA)). Renal superoxide dismutase (SOD), malondialdehyde (MDA), and oxidative stress-related Nrf2/HO-1 signaling pathways were measured. The expression of the inflammatory markers TNF-α, IL-6, MCP-1, and NF-κB was assessed by ELISA and western blotting. Finally, the expression of the PI3K/Akt signaling pathway was detected by western blotting. Glycerol administration induced obvious renal histologic damage and increased Scr, urea, and PCNA expression. Notably, thymol treatment attenuated these structural and functional changes and prevented renal oxidative stress, inflammatory damage and PI3K/Akt pathway downregulation associated with glycerol-induced AKI. In conclusion, thymol might have potential applications in the amelioration of AKI via its antioxidant and anti-inflammatory effects and upregulation of the PI3K/Akt signaling pathway.

Novel studies on Isolation, purification and characterization of dibenzonitro compound from Glycosmis pentaphylla (Retz.) DC. and effect in downregulating neuronal cancers

To isolate Letrozole from Glycosmis pentaphylla (Retz.) DC. and to determine its effect on regulating the proliferation, cell cycle distribution, apoptosis and key mechanisms in human neuroblastoma cell lines. Letrozole was isolated through column chromatographic technique and its effect was checked on human neuroblastoma cell lines, IMR 32. The effects of Letrozole on cell viability were measured by MTT assay, and the cell cycle distribution was determined by flow cytometry. The expression changes in mRNA of proliferating cell nuclear antigen (PCNA), cyclin D1 and Bcl-xL were taken from real-time PCR analysis and the protein levels were detected by Western blotting. The results of the present study showed that Letrozole, isolated from leaves of G. pentaphylla could cause significant inhibitory effect on proliferation of IMR 32 cells in a dose dependent manner. Cell arrest was obtained at S phase with the treatment of Letrozole. Apart from this, the expression of PCNA, cyclin D1 and Bcl-xL were decreased both at mRNA and protein levels for the same treatment. Letrozole can inhibit proliferation, induce cell arrest and cause apoptosis in IMR 32 cell lines. The decreased expression of PCNA, cyclin D1 and Bcl-xL induced by Letrozole contributes to the above effects in vitro. This is the first report on the isolation of Letrozole from G. pentaphylla.

Knockdown of circ_0113656 assuages oxidized low-density lipoprotein-induced vascular smooth muscle cell injury through the miR-188-3p/IGF2 pathway.

Circular RNA (circRNA) is involved in the pathogenesis of atherosclerosis (AS). The present work analyzed the RNA expression of circ_0113656, microRNA-188-3p (miR-188-3p), and insulin-like growth factor 2 (IGF2) by quantitative real-time polymerase chain reaction. The protein expression of proliferating cell nuclear antigen (PCNA), matrix metalloprotein 2 (MMP2), and IGF2 was detected by Western blotting. Cell viability, proliferation, invasion, and migration were analyzed using the cell counting kit-8, 5-ethynyl-2'-deoxyuridine, transwell invasion, and wound-healing assays, respectively. The interactions among circ_0113656, miR-188-3p, and IGF2 were identified by dual-luciferase reporter assay and RNA immunoprecipitation assay. The results showed that circ_0113656 and IGF2 expression were significantly upregulated, while miR-188-3p was downregulated in the blood of AS patients and oxidized low-density lipoprotein (ox-LDL)-treated HVSMCs in comparison with controls. The ox-LDL treatment induced HVSMC proliferation, migration, and invasion accompanied by increases in PCNA and MMP2 expression; however, these effects were attenuated after circ_0113656 knockdown. Circ_0113656 acted as a miR-188-3p sponge and it regulated ox-LDL-induced HVSMC disorders by binding to miR-188-3p. Besides, the regulation of miR-188-3p in ox-LDL-induced HVSMC injury involved IGF2. Further, the depletion of circ_0113656 inhibited IGF2 expression by interacting with miR-188-3p. Thus, the circ_0113656/miR-188-3p/IGF2 axis may mediate ox-LDL-induced HVSMC disorders in AS, providing a new therapeutic strategy for AS.

Ketogenic diet inhibits neointimal hyperplasia by suppressing oxidative stress and inflammation

ABSTRACT Objective Neointimal hyperplasia is the primary mechanism underlying atherosclerosis and restenosis after percutaneous coronary intervention. Ketogenic diet (KD) exerts beneficial effects in various diseases, but whether it could serve as non-drug therapy for neointimal hyperplasia remains unknown. This study aimed to investigate the effect of KD on neointimal hyperplasia and the potential mechanisms. Methods and Results Carotid artery balloon-injury model was employed in adult Sprague-Dawley rats to induce neointimal hyperplasia. Then, animals were subjected to either standard rodent chow or KD. For in-vitro experiment, impacts of β-hydroxybutyrate (β-HB), the main mediator of KD effects, on platelet-derived growth factor BB (PDGF-BB) induced vascular smooth muscle cell (VSMC) migration and proliferation were determined. Balloon injury induced event intimal hyperplasia and upregulation of protein expression of proliferating cell nuclear antigen (PCNA) and α-smooth muscle actin (α-SMA), and these changes were significantly ameliorated by KD. In addition, β-HB could markedly inhibit PDGF-BB induced VMSC migration and proliferation, as well as inhibiting expressions of PCNA and α-SMC. Furthermore, KD inhibited balloon-injury induced oxidative stress in carotid artery, indicated by reduced ROS level, malondialdehyde (MDA) and myeloperoxidase (MPO) activities, and increased superoxide dismutase (SOD) activity. We also found balloon-injury induced inflammation in carotid artery was suppressed by KD, indicated by decreased expressions of proinflammatory cytokines IL-1β and TNF-α, and increased expression of anti-inflammatory cytokine IL-10. Conclusion KD attenuates neointimal hyperplasia through suppressing oxidative stress and inflammation to inhibit VSMC proliferation and migration. KD may represent a promising non-drug therapy for neointimal hyperplasia associated diseases.

BPA interferes with granulosa cell development and oocyte meiosis in mouse preantral follicles.

Bisphenol A (BPA) is an established environmental endocrine disruptor and can interfere with the development of female germ cells. However, the underlying mechanisms are still unclear. We investigated the effects of BPA on granulosa cell development and meiosis of oocytes using in vitro culture system of mouse preantral follicles. Preantral follicles from D14 mouse ovary were treated with 10 μg/mL BPA in vitro for 11 days. The adherent area of follicles was measured. On D11, cumulus cell expansion was observed. The meiosis recovery rate was calculated. Western blot detected P53, proliferating cell nuclear antigen (PCNA), estrogen receptor α (ERα), and cyclin B1. ELISA measured estrogen and progesterone levels. Immunofluorescence detected Cx37 on oocyte membrane. Gap junction communication was assessed. We found that BPA significantly promoted the expressions of PCNA and ERα in granulosa cells and the secretion of estrogen and progesterone by granulosa cells on D10 and significantly increased the attachment area of the follicles on D8 and D10. However, it reduced the expansion of cumulus cells, Cx37 expression, and the gap junction communication between cumulus cells and oocytes on D11. BPA promoted the recovery of oocytes from meiosis, interrupted the expression of cyclin B1 protein in arrested germinal vesicle breakdown (GVBD) oocytes, and reduced the in vitro maturation rate of oocytes. These GVBD oocytes were live without apoptosis or death. Conclusively, BPA disturbs the development of granulosa cells and the meiosis progression of oocytes by decreasing gap junction communication between oocytes and the granulosa cells as well as regulating cyclin B1 expression in GVBD oocytes.

Expression of eIF6 and its relationship with cell proliferation in colorectal adenocarcinoma

Abstract Objectives Eukaryotic translation initiation factors (eIFs) are genes related to tumor formation. They selectively translate some mRNAs, regulate protein synthesis, promote cell proliferation, and effectively control the progression of some tumors. As a member of this family, eukaryotic translation initiation factor 6 (eIF6) plays a crucial role in tumor formation and progression. Exploring the expression characteristics of eIF6 and proliferating cell nuclear antigen (PCNA), a proliferation-associated factor, in colorectal adenocarcinoma (CRAC) and analyzing their correlation and clinical significance can provide a theoretical basis for the study of CRAC and objective biological indicators for the clinical judgment of tumor formation and progression. Methods The GEPIA database was used to predict the trend of eIF6 and PCNA in CRAC. Sixty-four patients diagnosed with CRAC and undergoing surgical treatment were selected from January 2017 to November 2022. CRAC tissues and normal mucous tissues (>3 cm away from the tumor margin) were retained. The expression of eIF6 and PCNA was detected by immunohistochemistry (IHC). Colon cancer cell lines SW480, HCT15, and SW620 and normal colon cell line NCM460 were selected, and the expression of eFI6 and PCNA in these cells was detected by Western blot. Results A trend of elevated expression of eIF6 and PCNA was predicted in CRAC by the GEPIA database. The expression levels of eIF6 (65.63 % vs. 9.38 %, X2=43.2000, p<0.0001) and PCNA (84.38 % vs. 46.88 %, X2=19.9481, p<0.0001) were higher in CRAC tissues than that in normal mucosa as indicated by IHC. Significant difference in eIF6 and PCNA expression was found among different maxim tumor diameters and depths of infiltration in colon adenocarcinoma (p<0.05). No statistical difference in eIF6 and PCNA expression was observed among different genders, ages, degrees of differentiation, LNMets, intravascular cancer thrombosis, TNM stages, and numbers of lymph node metastases (p>0.05). A positive correlation was found between eIF6 and PCNA in CRAC (X2=5.05, r=0.77, p=0.0283). Their expression was significantly higher in SW480, HCT15, and SW620 than in NCM460 (p<0.05). Conclusions eIF6 is highly expressed in CRAC, participates in tumor formation and progression, and has a positive correlation with PCNA.

EZH2 activates Wnt/β-catenin signaling in human uterine fibroids, which is inhibited by the natural compound methyl jasmonate

To investigate the link between EZH2 and Wnt/β-catenin signaling and its role in uterine fibroids (UFs) pathogenesis and explore the potential effect of natural compound methyl jasmonate (MJ) against UFs. EZH2 overexpression or inhibition was achieved in human uterine leiomyoma (HuLM) cells using EZH2-expressing adenovirus or chemical EZH2 inhibitor (DZNep), respectively. The HuLM and normal uterine smooth muscle cells were treated with 0.1-3 mM of MJ, and several experiments were employed. Laboratory study. None. Methyl jasmonate. Protein expression of EZH2, β-catenin, and proliferating cell nuclear antigen (PCNA) was measured by Western blot as well as gene expression alterations of Wnt ligands (Wnt5A, Wnt5b, and Wnt9A), WISP1, CTNNB1, and its responsive gene PITX2 using quantitative real-time polymerase chain reaction. The protein and ribonucleic acid (RNA) levels of several markers were measured in MJ-treated or untreated HuLM cells, including EZH2 and β-catenin, extracellular matrix markers collagen type 1 (COL1A1) and fibronectin (FN), proliferation markers cyclin D1 (CCND1) and PCNA, tumor suppressor marker p21, and apoptotic markers (BAX, cytochrome c, and cleaved caspase 3). EZH2 overexpression significantly increased the gene expression of several Wnt ligands (PITX2, WISP1, WNT5A, WNT5B, and WNT9A), which increased nuclear translocation of β-catenin and PCNA and eventually HuLM cell proliferation. EZH2 inhibition blocked Wnt/β-catenin signaling activation where the aforementioned genes significantly decreased as well as PCNA, cyclin D1, and PITX2 protein expression compared with those in untreated HuLM. Methyl jasmonate showed a potent antiproliferative effect on HuLM cells in a dose- and time-dependent manner. Interestingly, the dose range (0.1-0.5 mM) showed a selective growth inhibitory effect on HuLM cells, not on normal uterine smooth muscle cells. Methyl jasmonate treatment at 0.5 mM for 24 hours significantly decreased both protein and RNA levels of EZH2, β-catenin, COL1A1, FN, CCND1, PCNA, WISP1, and PITX2 but increased the protein levels of p21, BAX, cytochrome, c and cleaved caspase 3 compared with untreated HuLM. Methyl jasmonate-treated cells exhibited down-regulation in the RNA expression of 36 genes, including CTNNB1, CCND1, Wnt5A, Wnt5B, and Wnt9A, and up-regulation in the expression of 34 genes, including Wnt antagonist genes WIF1, PRICKlE1, and DKK1 compared with control, confirming the quantitative real-time polymerase chain reaction results. Our studies provide a novel link between EZH2 and the Wnt/β-catenin signaling pathway in UFs. Targeting EZH2 with MJ interferes with the activation of wnt/β-catenin signaling in our model. Methyl jasmonate may offer a promising therapeutic option as a nonhormonal and cost-effective treatment against UFs with favorable clinical utility, pending proven safe and efficient in human clinical trials.

Proliferative Activity of Myoepithelial Cells in Normal and Diabetic Parotid Glands Based on Double Immunostaining Labeling

AIM: This study aimed to examine the effect of diabetes mellitus on the histology of parotid glands and to give a scientific overview of the distribution and the proliferative activity of myoepithelial cells (MECs) encircling both ducts and acini in parotid gland of both normal and diabetic mongrel dogs. MATERIALS AND METHODS: Twelve male mongrel dogs were used in the experiment and divided into two equal groups, group I, control group, group II, dogs with alloxan-induced diabetes. The dogs of the group II were injected by fresh preparation of a single dose of 100 mg/kg body weight of alloxan monohydrate dissolved in physiological saline. Ten days later, blood glucose level was determined using enzymatic colorimetric test; dogs presented a glucose level at or above 200 mg/dL were included in the diabetic group of the experiment. Three months later, dogs were sacrificed and the parotid glands from all groups were dissected and prepared for histological examination and double immunohistochemical expression of both actin and proliferating cell nuclear antigen (PCNA). RESULTS: Histological findings using H and E staining confirmed that the parotid gland parenchyma of the diabetic group had glandular atrophy characterized by loss of normal gland structure, acinar degeneration, and dilatation of the duct system with the presence of duct like structure. Moreover, there was a predominance of the fibrous component with the presence of fat cells within the gland compartments. Immunohistochemical findings of parotid gland of control group revealed positive scattered actin staining of weak to mild quantity in cells embracing some acini and intralobular ducts. Expression of PCNA in actin-positive cells revealed few scattered reactions embracing some acini and small ducts. Parotid gland of diabetic dogs revealed positive actin staining of mild-to-moderate quantity in the cells encircling the acini, intralobular, and some interlobular ducts. Expression of PCNA in actin- positive cells revealed mild-to-moderate positive reaction more concentrated in the cells surrounding both acini and intercalated ducts. CONCLUSION: Routine histological findings of diabetic dogs in our findings showed abundant pathological changes in parenchymal tissue elements, including acinar, ductal, and MECs that had a significant impact on saliva production and secretion resulting in dry mouth. The proliferative activity of MECs in the control group indicated a routine regeneration process, whereas the abundant proliferative activity in the diabetic group might indicate pathological transformation rather than regeneration, especially because no remedial measures were taken during this investigation.

Effect of thermal manipulation during embryogenesis on gene expression of myogenic upstream activation factors pre- and post-hatch in broilers

This study aimed to determine the optimum timing of embryonic thermal manipulation (TM) that may result in improvement of mRNA expression of myogenic upstream activation factors viz. Wnt family member-3 (Wnt-3), sonic hedgehog gene (Shh), proliferating cell nuclear antigen (PCNA) and paired-box transcription factor-7 (Pax-7) during development and histogenesis of broiler muscle. Fertile eggs (1440) were divided randomly and equally into 5 treatment groups including control (no TM) and four treatment groups (TM1, TM2 TM3 and TM4) that were daily subjected to 39 ̊C for 18 h with 65% relative humidity during embryonic days ED 7–11, ED 11–15, ED 15–18 and ED 7–18 respectively. Pectoral and thigh muscle mRNA expressions of myogenic upstream activation factors were evaluated by semi-quantitative real-time RT-PCR. Out of TM conditions that were investigated, TM1 resulted in a significant improvement of Wnt-3, Shh, PCNA and Pax-7 expressions in broiler pectoral and thigh muscles during embryonic and post-hatch life when compared to the control. Thus, thermal manipulation during early embryongenesis (embryonic days ED 7-11) enhance broiler skeletal muscle myoblast proliferation by triggering and inducing transcription factors that regulates myogenesis and subsequently may lead to improve cell number and size of skeletal muscle. The outcome of this study indicates that TM during ED7-11 improved muscle response to heat stress, was safe to the pectoral and thigh muscles and this method may enhance myogenesis and muscle growth in a positive manner.

Terpinen-4-ol inhibits proliferation of VSMCs exposed to high glucose via regulating KLF4/NF-κB signaling pathway

This study aimed to observe the effect of terpinen-4-ol(T4O) on the proliferation of vascular smooth muscle cells(VSMCs) exposed to high glucose(HG) and reveal the mechanism via the Krüppel-like factor 4(KLF4)/nuclear factor kappaB(NF-κB) signaling pathway. The VSMCs were first incubated with T4O for 2 h and then cultured with HG for 48 h to establish the model of inflammatory injury. The proliferation, cell cycle, and migration rate of VSMCs were examined by MTT method, flow cytometry, and wound healing assay, respectively. The content of inflammatory cytokines including interleukin(IL)-6 and tumor necrosis factor-alpha(TNF-α) in the supernatant of VSMCs was measured by enzyme-linked immunosorbent assay(ELISA). Western blot was employed to determine the protein levels of proliferating cell nuclear antigen(PCNA), Cyclin D1, KLF4, NF-κB p-p65/NF-κB p65, IL-1β, and IL-18. The KLF4 expression in VSMCs was silenced by the siRNA technology, and then the effects of T4O on the cell cycle and protein expression of the HG-induced VSMCs were observed. The results showed that different doses of T4O inhibited the HG-induced proliferation and migration of VSMCs, increased the percentage of cells in G_1 phase, and decreased the percentage of cells in S phase, and down-regulated the protein levels of PCNA and Cyclin D1. In addition, T4O reduced the HG-induced secretion and release of the inflammatory cytokines IL-6 and TNF-α and down-regulated the expression of KLF4, NF-κB p-p65/NF-κB p65, IL-1β, and IL-18. Compared with si-NC+HG, siKLF4+HG increased the percentage of cells in G_1 phase, decreased the percentage of cells in S phase, down-regulated the expression of PCNA, Cyclin D1, and KLF4, and inhibited the activation of NF-κB signaling pathway. Notably, the combination of silencing KLF4 with T4O treatment further promoted the changes in the above indicators. The results indicate that T4O may inhibit the HG-induced proliferation and migration of VSMCs by down-regulating the level of KLF4 and inhibiting the activation of NF-κB signaling pathway.

Co-Expression of Chromatin Assembly Factor 1 Subunit A and Proliferating Cell Nuclear Antigen Is a Prognostic Biomarker of Esophageal Cancer

(1) Background: Esophageal cancer (EC) is an important global health challenge. Due to the lack of necessary biomarkers and therapeutic targets, the survival of EC patients is poor. The EC proteomic data of 124 patients recently published by our group provides a database for research in this field. (2) Methods: Bioinformatics analysis was used to identify DNA replication and repair-related proteins in EC. Proximity ligation assay, colony formation assay, DNA fiber assay, and flow cytometry were used to study the effects of related proteins on EC cells. Kaplan–Meier survival analysis was used to evaluate the relationship between gene expression and the survival time of EC patients. (3) Results: Chromatin assembly factor 1 subunit A (CHAF1A) was highly correlated with proliferating cell nuclear antigen (PCNA) expression in EC. CHAF1A and PCNA colocalized in the nucleus of EC cells. Compared with the knockdown of CHAF1A or PCNA alone, the double knockdown of CHAF1A and PCNA could significantly inhibit EC cell proliferation. Mechanistically, CHAF1A and PCNA synergistically accelerated DNA replication and promoted S-phase progression. EC patients with high expression of both CHAF1A and PCNA had a worse survival rate. (4) Conclusion: we identify CHAF1A and PCNA as key cell cycle-related proteins leading to the malignant progression of EC, and these proteins could serve as important prognostic biomarkers and targets for EC.

Effect of platelet-derived growth factor-BB on pulmonary vascular remodeling in neonatal rats with hypoxic pulmonary hypertension and its mechanism

To study the effect of platelet-derived growth factor-BB (PDGF-BB) on pulmonary vascular remodeling in neonatal rats with hypoxic pulmonary hypertension (HPH). A total of 128 neonatal rats were randomly divided into four groups: PDGF-BB+HPH, HPH, PDGF-BB+normal oxygen, and normal oxygen (n=32 each). The rats in the PDGF-BB+HPH and PDGF-BB+normal oxygen groups were given an injection of 13 μL 6×1010 PFU/mL adenovirus with PDGF-BB genevia the caudal vein. After 24 hours of adenovirus transfection, the rats in the HPH and PDGF-BB+HPH groups were used to establish a neonatal rat model of HPH. Right ventricular systolic pressure (RVSP) was measured on days 3, 7, 14, and 21 of hypoxia. Hematoxylin-eosin staining was used to observe pulmonary vascular morphological changes under an optical microscope, and vascular remodeling parameters (MA% and MT%) were also measured. Immunohistochemistry was used to measure the expression levels of PDGF-BB and proliferating cell nuclear antigen (PCNA) in lung tissue. The rats in the PDGF-BB+HPH and HPH groups had a significantly higher RVSP than those of the same age in the normal oxygen group at each time point (P<0.05). The rats in the PDGF-BB+HPH group showed vascular remodeling on day 3 of hypoxia, while those in the HPH showed vascular remodeling on day 7 of hypoxia. On day 3 of hypoxia, the PDGF-BB+HPH group had significantly higher MA% and MT% than the HPH, PDGF-BB+normal oxygen, and normal oxygen groups (P<0.05). On days 7, 14, and 21 of hypoxia, the PDGF-BB+HPH and HPH groups had significantly higher MA% and MT% than the PDGF-BB+normal oxygen and normal oxygen groups (P<0.05). The PDGF-BB+HPH and HPH groups had significantly higher expression levels of PDGF-BB and PCNA than the normal oxygen group at all time points (P<0.05). On days 3, 7, and 14 of hypoxia, the PDGF-BB+HPH group had significantly higher expression levels of PDGF-BB and PCNA than the HPH group (P<0.05), while the PDGF-BB+normal oxygen group had significantly higher expression levels of PDGF-BB and PCNA than the normal oxygen group (P<0.05). Exogenous administration of PDGF-BB in neonatal rats with HPH may upregulate the expression of PCNA, promote pulmonary vascular remodeling, and increase pulmonary artery pressure.

PCNA promotes PRRSV replication by increasing the synthesis of viral genome

Porcine reproductive and respiratory syndrome virus (PRRSV) is an RNA virus belonging to the Arteriviridae family. Currently, the strain has undergone numerous mutations, bringing massive losses to the swine industry worldwide. Despite several studies had been conducted on PRRSV, the molecular mechanisms by which it causes infection remain unclear. Proliferating cell nuclear antigen (PCNA) is a sign of DNA damage and it participates in DNA replication and repair. Therefore, in this study, we investigated the potential role of PCNA in PRRSV infection. We observed that PCNA expression was stable after PRRSV infection in vitro; however, PCNA was translocated from the nucleus to the cytoplasm. Notably, we found the redistribution of PCNA from the nucleus to the cytoplasm in cells transfected with the N protein. PCNA silencing inhibited PRRSV replication and the synthesis of PRRSV shorter subgenomic RNA (sgmRNA) and genomic RNA (gRNA), while PCNA overexpression promoted virus replication and PRRSV shorter sgmRNA and gRNA synthesis. By performing immunoprecipitation and immunofluorescence colocalization, we confirmed that PCNA interacted with replication-related proteins, namely NSP9, NSP12, and N, but not with NSP10 and NSP11. Domain III of the N protein (41–72 aa) interacted with the IDCL domain of PCNA (118–135 aa). Therefore, we propose cytoplasmic transport of PCNA and its subsequent influence on PRRSV RNA synthesis could be a viral strategy for manipulating cell function, thus PCNA is a potential target to prevent and control PRRSV infection.

Abstract 335: Ubiquitin Specific Peptidase 37promotes Osteosarcoma oncogenesis by interacting with PCNA and impacting constitutive replication fork movement.

Abstract Osteosarcoma is the heterogeneous primary malignancy of bone which is most commonly found among children and adolescents. Recent data related to treatment of osteosarcoma indicates the lack information about the progression of the disease. Osteosarcoma has been a challenge for the oncologist because even after surgical removal of primary tumors many patients go on to develop pulmonary metastasis. Protein deubiquitination controls many intracellular processes, including cell cycle progression, transcriptional activation, and signal transduction. Ubiquitin specific peptidases (USPs) remove ubiquitin tags from target proteins to alter protein configuration and function. Recent studies have revealed that Ubiquitin specific peptidase 37 (UPS37) regulates replication stress by regulating important protein involved in several important cellular functions. Analysis of TCGA data indicated that overexpression of USP37 correlated with reduced progression free survival (PFS) in osteosarcoma patients. Next generation sequencing (NGS) analysis of osteosarcoma cells indicated that distinct set of genes were altered on overexpression or knockdown of USP37. Our data indicate that USP37 overexpression confers survival advantage while its depletion enhances sensitivity for cell killing in osteosarcoma cells due to replication stress. USP37 overexpressing cells were able to resolve DNA damage foci much more rapidly than the control cells or cells in which USP37 was depleted in response to genotoxic stress. USP37 depletion results in reduced resolution of γ H2AX and 53BP1 DNA damage foci and increase in number of collapsed replication fork which indicates the reduced ability of cells to carry out constitutive DNA replication. USP37 was found to interact with PCNA (Proliferative cell nuclear antigen). Interestingly docking studies indicated that USP37 and PCNA interacted with stronger affinity in presence of double stranded DNA through different residues. We further correlated our data with archived tissue blocks of osteosarcoma patients by analyzing if USP37 and PCNA expression colocalized. Present data suggests that USP37 is required for tolerance of replication stress as it interacts with PCNA which is required to dock additional replication factors and stabilize DNA replication fork. The current data provides new mechanistic details for the regulation of replication stress by USP37 which merits the development of targeting strategies to explore its therapeutic potential in osteosarcoma by inducing synthetic lethality. Citation Format: Ravi Chauhan, Lakshay Malhotra, Ashna Gupta, Ajaz Bhat, Gunjan Dagar, Tariq Masoodi, Muzafar A. Macha, Ethayathulla Abdul Samath, Atul Batra, Mehar Chand Sharma, Mohammad Haris, Ammira Al-Shabeeb Akil, Tej K. Pandita, Shahab Uddin, Mayank Singh. Ubiquitin Specific Peptidase 37promotes Osteosarcoma oncogenesis by interacting with PCNA and impacting constitutive replication fork movement. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 335.

Gene therapy with urokinase-type plasminogen activator regenerates liver tissue.

Gene therapy using urokinase-type plasminogen activator (uPA) has been shown to induce extracellular matrix degradation, hepatocyte proliferation and liver tissue function restoration in liver cirrhosis models. Physiologically, uPA activates plasminogen conversion to plasmin, which leads, depending on the organ, to thrombolysis or extracellular matrix degradation. The purpose of this study was to compare the regenerative effect of gene therapy with adenoviruses encoding wild-type uPA (huPA), as well as its truncated isoform (ΔhuPA), in healthy and cirrhotic animals. In addition, possible adverse effects on coagulation were assessed. 6 x 1011 vp/kg of Ad-huPA or Ad-ΔhuPA were administered via the iliac vein to healthy male Wistar rats or to male Wistar rats with cirrhosis induced by chronic poisoning with carbon tetrachloride (CCl4). The animals were sacrificed at day 2, 4 or 6 post-treatment. Liver fibrosis, proliferating cell nuclear antigen expression, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) serum levels and coagulation markers were evaluated. On day 6 post-treatment, a fibrosis reversal of 48.7-41.5% was achieved. AST and ALT levels did not change in cirrhotic animals treated with ΔhuPA, but showed an elevation in healthy animals. Cell proliferation increased in healthy and cirrhotic animals with both transgene isoforms. No coagulation adverse effects were observed in the ΔhuPA group, and by day 6, they had disappeared in the huPA group. Gene therapy with Ad-huPA and Ad-ΔhuPA favors cell proliferation in cirrhotic animals, without important side effects.

The influence of alpha-lipoic acid on ovarian follicle growth in induced aging mice

The ovary contains follicles at various developmental stages. The present study aimed to investigate the antioxidant efficiency of alpha-lipoic acid (α-LA) on follicle growth in induced aging ovaries. Juvenile female mice (n=24) were allocated into four groups (n=6, each); the control group received distilled water, and the induced aging group (T1) received D-galactose (300 mg/kg). The co-administrated group (T2) was treated with α-LA (300 mg/kg) and D-galactose (100 mg/kg), while the fourth group (T3) was treated with α-LA (100 mg/kg). At the end of treatments (8 weeks), animals were sacrificed, and ovaries were processed for hematoxylin and eosin staining and immunostaining for proliferating cell nuclear antigen (PCNA). PCNA was detectable in oocytes but only in granulosa cells of activated follicles. The D-galactose treatment successfully induced ovarian aging as the proportion of primordial and growing follicles was significantly reduced accompanied by massively increased atretic follicles. Additionally, only numerous PCNA positively stained follicles were recognized. The co-administrated α-LA moderately rescued the characteristics of ovarian aging. Mice treated with α-LA demonstrated a substantial increase in the population of atretic follicles, antral follicles, and PCNA positively stained follicles. There was no change in oocyte size at any follicle growth stage among groups. In conclusion, α-LA moderately rescued the detrimental impacts of induced ovarian aging. For the first time, the expression of PCNA was linked with ovarian aging, where PCNA-staining has been recognized as a valuable tool to evaluate the proliferative activity of the granulosa cells.

Effects of Interferon-γ and Interleukin-4 on Proliferating Cell Nuclear Antigen Expression in Transplanted Bone Tumor Tissue

The rabbit VX2 bone tumor model is an ideal animal model for studying malignant bone tumors. Cytokines have been reported to play a role in tumor initiation and promotion, angiogenesis, and metastasis. However, few studies have investigated the relationship between cytokines and VX2 bone tumor development. This study investigated the effect of interferon-γ (IFN-γ) and interleukin-4 (IL-4) on proliferating cell nuclear antigen (PCNA) expression in tumor tissue. Thirty Japanese white rabbits were randomly divided into group A (n = 15) and group B (n = 15). The rabbit VX2 bone tumor model was constructed by implanting VX2 tumors on the medial side of the upper tibia. Group A was sacrificed in the first week of implantation, and group B in the second week of implantation. Peripheral venous blood, tumor tissue from the medullary cavity at the implantation site, and surrounding bone and soft tissue were harvested before implantation and execution in both experimental groups. IFN-γ and IL-4 expression levels in peripheral blood and PCNA levels in tumor tissues were measured by enzyme-linked immunosorbent assay (ELISA). The tumor tissue of the medullary cavity and surrounding bone and soft tissue was harvested for pathological examination. By the end of the experiment, 30 rabbits were included in the study. There was no significant difference in IFN-γ, IL-4 and PCNA expression levels in group A compared to group B before implantation (t = 1.187, p value = 0.255; t = 1.282, p value = 0.221; t = 0.499, p value = 0.626). IFN-γ and IL-4 expression levels before execution in group A were not significantly different from those before implantation (t = -1.280, p value = 0.213; t = 0.952, p value = 0.349), and PCNA expression levels were higher than those before implantation (t = 2.469, p value = 0.020). Group B had significantly lower IFN-γ expression levels before execution than before implantation (t = -3.741, p value = 0.001) and significantly higher IL-4 and PCNA expression levels before execution than before implantation (t = 6.279, p value < 0.01; t = 13.031, p value < 0.001). IFN-γ expression levels before execution in group B was significantly lower than those before execution in group A (t = 17.184, p value < 0.001), and IL-4 and PCNA expression before execution in group B was significantly higher than that before execution in group A (t = -26.235, p value < 0.001; t = -24.619, p value < 0.001). The correlation between IFN-γ and PCNA levels before execution in groups A and B was negative (r = -0.566, p value = 0.028; r = -0.604, p value = 0.017), and the correlation between IL-4 and PCNA levels was positive (r = 0.583, p value = 0.023; r = 0.884, p value < 0.001). In the rabbit VX2 bone tumor model, extending the period of time after tumor implantation resulted in a negative correlation between IFN-γ and PCNA levels and a positive correlation between IL-4 and PCNA levels.

Curcumin Alleviates Thioacetamide-Induced Kidney Toxicity in Rats: Enhancing Antioxidant System, and Attenuating Oxidative Stress, DNA Damage, and Inflammation

Thioacetamide (TAA), well-known as a toxic agent and has been reported to be nephrotoxic due to oxidative stress induction and proinflammatory markers increase. Curcumin has been shown in various studies to have antioxidant and anti-inflammatory properties. This study aimed to investigate the ameliorative effect of curcumin against TAA-induced kidney toxicity in rats. In this study, 28 male albino rats were used, and kidney toxicity was induced by intraperitoneal injection of TAA at a dose of 200mg/kg, twice a week for 8 weeks then the rats were treated with curcumin at a dose of 200mg/kg, orally, daily for 2 weeks. Kidney functions in all the experimental groups as well as oxidative stress (MDA), catalase (CAT), and superoxide dismutase (SOD) were determined. In addition, DNA damage and the expression status of both proinflammatory cytokine (TNFα) and proliferating cell nuclear antigen (PCNA) were evaluated. Further, light microscopic studies were performed on kidney specimens. Our results demonstrated that TAA had a nephrotoxic effect, as evidenced by significantly increase in kidney functions as well as substantially increase in renal MDA associated with reduction in CAT and SOD antioxidant enzymes compared to control group. The administration of curcumin ameliorates the oxidative stress and upregulate the antioxidant parameters. Further, a signification increases in DNA damage, TNFα, and PCNA expression was seen in TAA-group which was then alleviated by curcumin treatment. In conclusion, the ameliorative effect of curcumin could be attributed to its ability to minimize oxidative stress, renal cell injury, and cytokine release.