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BACKGROUND: Proliferating cell nuclear antigen (PCNA) is essential for DNA replication and repair, cell growth, and survival. PCNA also enhances androgen receptor (AR) signaling in prostate cancer (PC) cells. We identified a PCNA interaction protein (PIP) box at the N-terminal domain of AR and developed a small peptide PCNA inhibitor R9-AR-PIP containing AR PIP-box. We also identified a series of small molecule PCNA inhibitors (PCNA-Is) that bind directly to PCNA and interrupt PCNA functions. The present study investigated the effects of the PCNA inhibitors on the sensitivity of PC cells to X-ray radiation. METHODS: The effects of targeting PCNA on radio sensitivity of PC cells were investigated in four lines of castration-resistant PC (CRPC) cells with different AR expression statuses. The cells were treated with the PCNA inhibitors and X-ray radiation alone or in combination. The effects of the treatment on expression of AR target genes, DNA damage response, DNA damage, homologous recombination repair (HRR), and cytotoxicity were evaluated. RESULTS: We found that the androgen response element (ARE) occupancy of the DNA damage response gene PARP1 by AR is significantly attenuated by PCNA-I1S or R9-AR-PIP combined with X-ray radiation, while X-ray radiation alone does not enhance the ARE occupancy. PCNA-I1S or R9-AR-PIP alone significantly inhibits occupancy of the AR-occupied regions (AROR) in PRKDC and XRCC2 genes. R9-AR-PIP and PCNA-I1S inhibit expression of AR-Vs target gene cyclin A2 and show the additive effects with radiation in AR-positive CRPC cells. Targeting PCNA by PCNA-I1S and R9-AR-PIP downregulates expression of DNA damage response genes EXO1, Rad54L, Rad51, and/or PARP1 and shows the additive effects with radiation as compared with their respective controls in AR-positive CRPC LNCaP-AI, 22Rv1, and R1-D567 cells, but not in AR-negative PC-3 cells. R9-AR-PIP and PCNA-I1S elevate the levels of phospho-DNA-PKcs(S2056) and γH2AX, indicating DNA damage in response to radiation in AR-positive cells. The HRR is significantly attenuated by PCNA inhibitors PCNA-I1S, R9-AR-PIP, and T2AA in all four CRPC cells examined, and inhibited by Enzalutamide (Enz) only in 22RV1 cells. The cytotoxicity induced by X-ray radiation in androgen-dependent LNCaP cells is enhanced by Enz and a lower concentration of R9-AR-PIP in the colony formation assay. R9-AR-PIP at higher concentration reduces the colony formation and has an additive effect with X-ray radiation in all AR expressing cells, regardless of AR-FL and AR-Vs, but does not significantly alter the colony formation in AR-negative PC-3 cells. PCNA-I1S attenuates colony formation and has an additive effect with ionizing radiation in all four CRPC cells, regardless of AR expression status. CONCLUSION: These data provide a strong rationale for the therapy studies using PCNA-I1S or R9-AR-PIP in combination with X-ray radiation against CRPC tumors in preclinical models.
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This study was designed to investigate the effects of vitamin D and mannitol in an experimental rat ovarian torsion model. Thirty-two female Wistar albino rats were randomly classified as group 1: (sham), group 2: (detorsion), group 3: (detorsion + mannitol), group 4: (detorsion + vitamin D) and group 5: (detorsion + mannitol + vitamin D) (for each group n = 8). All groups were subjected to bilateral adnexal torsion for 2 h except for group 1. Bilateral adnexal detorsion was performed in all groups except for group 1. Groups 3 and 5 intraperitoneally received the injection of mannitol at a dose of 0.3 mg/kg 30 min before detorsion. Also, the group's 4 and 5 orally received vitamin D in a dose of 500 IU/kg/day for two weeks before torsion. Total oxidant status (TOS), total antioxidant status (TAS), oxidative stress index (OSI) and proliferating cell nuclear antigen (PCNA) levels were analyzed. According to the histopathological analyses, ovarian tissue damage and follicle counting were evaluated. TOS, OSI and histopathologic score values of ovarian tissue were significantly lower in group 5 than groups 2, 3 and 4 (p < 0.05). The PCNA level was significantly higher in group 5 than in groups 2, 3 and 4 (p < 0.05). A strong negative correlation was found between OSI and PCNA in groups 2, 3, 4 and 5 (r = -0.92, p = 0.01; r = -0.98, p < 0.0001; r = -0.98, p < 0.0001 and r = -0.96, p = 0.0002, respectively). The numbers of primordial follicles in group 5 (p < 0.001) and primary follicles in group 4 (p < 0.001) were significantly higher when compared to group 2. Based on the results of this study, it could be suggested that combination treatment of mannitol with vitamin D is more effective in reversing tissue damage induced by ischemia-reperfusion (I/R) injury in the ovarian torsion model than administration of only an agent.
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Proliferating cell nuclear antigen (PCNA), the homotrimeric eukaryotic sliding clamp protein, recruits and coordinates the activities of a multitude of proteins that function on DNA at the replication fork. Chromatin assembly factor 1 (CAF-1), one such protein, is a histone chaperone that deposits histone proteins onto DNA immediately following replication. The interaction between CAF-1 and PCNA is essential for proper nucleosome assembly at silenced genomic regions. Most proteins that bind PCNA contain a PCNA-interacting peptide (PIP) motif, a conserved motif containing only eight amino acids. Precisely how PCNA is able to discriminate between binding partners at the replication fork using only these small motifs remains unclear. Yeast CAF-1 contains a PIP motif on its largest subunit, Cac1. We solved the crystal structure of the PIP motif of CAF-1 bound to PCNA using a new strategy to produce stoichiometric quantities of one PIP motif bound to each monomer of PCNA. The PIP motif of CAF-1 binds to the hydrophobic pocket on the front face of PCNA in a similar manner to most known PIP-PCNA interactions. However, several amino acids immediately flanking either side of the PIP motif bind the IDCL or C-terminus of PCNA, as observed for only a couple other known PIP-PCNA interactions. Furthermore, mutational analysis suggests positively charged amino acids in these flanking regions are responsible for the low micromolar affinity of CAF-1 for PCNA, whereas the presence of a negative charge upstream of the PIP prevents a more robust interaction with PCNA. These results provide additional evidence that positive charges within PIP-flanking regions of PCNA-interacting proteins are crucial for specificity and affinity of their recruitment to PCNA at the replication fork.
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Factor 1 de Ensamblaje de la Cromatina , Modelos Moleculares , Antígeno Nuclear de Célula en Proliferación , Unión Proteica , Saccharomyces cerevisiae , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Sitios de Unión , Factor 1 de Ensamblaje de la Cromatina/metabolismo , Factor 1 de Ensamblaje de la Cromatina/química , Factor 1 de Ensamblaje de la Cromatina/genética , Cristalografía por Rayos X , Antígeno Nuclear de Célula en Proliferación/metabolismo , Antígeno Nuclear de Célula en Proliferación/química , Antígeno Nuclear de Célula en Proliferación/genética , Conformación Proteica , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genéticaRESUMEN
Objective: To establish a model based on clinical and delta-radiomic features within ultrasound images using XGBoost machine learning to predict proliferation-associated nuclear antigen Ki-67 value ≥ 15% in T2NXM0 stage primary breast cancer (BC). Method: Data were collected from 228 randomly selected BC patients who received ultrasound screening and postoperative pathologic assessment from April 2015 to September 2018. The patients were classified into the study group (n = 80) and control group (n = 148), and the data were apportioned into the training set and test set at a 7:3 ratio based on time intervals. In the training set, crucial factors were identified from clinical features and grayscale and delta-radiomic features within ultrasound images, by using the chi-square test, t-test, and rank-sum test. The clinical model, imaging model, and combined model were built using multivariate logistic regression, respectively. The model's predictive performance and clinical net benefit were assessed using DeLong's method and decision curve analysis. Meanwhile, an XGBoost algorithm is used to establish a prediction model to verify the above results. Results: The crucial factors affecting Ki-67 value ≥ 15% included BMI, lymph node metastases, BC volume, CA153, pathology type, tumor boundaries, tumor morphology, elastography score, and delta-radscore. The predictive performance of the combined model [AUC 0.857, OR 0.0290, 95% CI 0.793-0.908] was considerably improved on the training set than the clinical model [AUC 0.724, OR 0.0422, 95% CI 0.648-0.792] and the imaging model [AUC 0.798, OR 0.0355, 95% CI 0.727-0.857]. The decision curve analysis also confirmed that the combined model delivered a higher clinical net benefit, and the verification on the test set yielded similar results. The nomogram and the calibration curve plotted based on the combined model achieved satisfactory clinical effects. The SHAP value of the XGBoost algorithm also confirmed that lymph node metastasis, BC volume, elastography score, and delta-radscore are the best independent factors for predicting BC Ki-67 value ≥ 15%. Conclusion: The XGBoost machine learning-based combined model integrating clinical features and delta-radiomic features on ultrasound images was able to predict the Ki-67 value ≥ 15% in an efficient and noninvasive manner, providing important clues for clinical decision-making and follow-up in BC.
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Neoplasias de la Mama , Antígeno Ki-67 , Aprendizaje Automático , Terapia Neoadyuvante , Estadificación de Neoplasias , Humanos , Femenino , Neoplasias de la Mama/patología , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/terapia , Antígeno Ki-67/metabolismo , Persona de Mediana Edad , Estudios de Seguimiento , Terapia Neoadyuvante/métodos , Adulto , Pronóstico , Ultrasonografía/métodos , Anciano , Biomarcadores de Tumor , Curva ROC , RadiómicaRESUMEN
The amyloid-beta peptide (Aß) is the neurotoxic component in senile plaques of Alzheimer's disease (AD) brains. Previously we have reported that Aß toxicity is mediated by the induction of sonic hedgehog (SHH) to trigger cell cycle re-entry (CCR) and apoptosis in post-mitotic neurons. Basella alba is a vegetable whose polysaccharides carry immunomodulatory and anti-cancer actions, but their protective effects against neurodegeneration have never been reported. Herein, we tested whether polysaccharides derived from Basella alba (PPV-6) may inhibit Aß toxicity and explored its underlying mechanisms. In differentiated rat cortical neurons, Aß25-35 reduced cell viability, damaged neuronal structure, and compromised mitochondrial bioenergetic functions, all of which were recovered by PPV-6. Immunocytochemistry and western blotting revealed that Aß25-35-mediated induction of cell cycle markers including cyclin D1, proliferating cell nuclear antigen (PCNA), and histone H3 phosphorylated at Ser-10 (p-Histone H3) in differentiated neurons was all suppressed by PPV-6, along with mitigation of caspase-3 cleavage. Further studies revealed that PPV-6 inhibited Aß25-35 induction of SHH; indeed, PPV-6 was capable of suppressing neuronal CCR and apoptosis triggered by the exogenous N-terminal fragment of sonic hedgehog (SHH-N). Our findings demonstrated that, in the fully differentiated neurons, PPV-6 exerts protective actions against Aß neurotoxicity via the downregulation of SHH to suppress neuronal CCR and apoptosis.
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Péptidos beta-Amiloides , Apoptosis , Ciclo Celular , Proteínas Hedgehog , Neuronas , Polisacáridos , Péptidos beta-Amiloides/metabolismo , Péptidos beta-Amiloides/toxicidad , Proteínas Hedgehog/metabolismo , Animales , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Apoptosis/efectos de los fármacos , Ratas , Polisacáridos/farmacología , Polisacáridos/química , Ciclo Celular/efectos de los fármacos , Fragmentos de Péptidos , Supervivencia Celular/efectos de los fármacos , Fármacos Neuroprotectores/farmacologíaRESUMEN
The critical developmental stages of the embryo are strongly influenced by the dietary composition of the mother. Acrylamide is a food contaminant that can form in carbohydrate-rich foods that are heat-treated. The aim of this study was to investigate the toxicity of a relatively low dose of acrylamide on the development of the neural tube in the early stage chick embryos. Specific pathogen-free fertilized eggs (n = 100) were treated with acrylamide (0.1, 0.5, 2.5, 12.5 mg/kg) between 28-30th hours of incubation and dissected at 48th hours. In addition to morphological and histopathological examinations, proliferating cell nuclear antigen (PCNA) and caspase 3 were analyzed immunohistochemically. The brain and reproductive expression gene (BRE) was analyzed by RT-PCR. Acrylamide exposure had a negative effect on neural tube status even at a very low dose (0.1 mg/kg) (p < 0.05). Doses of 0.5 mg/kg and above caused a delay in neural tube development (p < 0.05). Crown-rump length and somite count decreased dose-dependently, while this decrease was not significant in the very low dose group (p > 0.05), which was most pronounced at doses of 2.5 and 12.5 mg/kg (p < 0.001). Acrylamide exposure dose-dependently decreased PCNA and increased caspase 3, with this change being significant at doses of 0.5 mg/kg and above (p < 0.001). BRE was downregulated at all acrylamide exposures except in the very low dose group (0.1 mg/kg). In conclusion, we find that acrylamide exposure (at 0.5 mg/kg and above) in post-gastrulation delays neural tube closure in chicken embryos by suppressing proliferation and apoptosis induction and downregulating BRE gene expression.
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Acrilamida , Relación Dosis-Respuesta a Droga , Desarrollo Embrionario , Antígeno Nuclear de Célula en Proliferación , Animales , Embrión de Pollo , Acrilamida/toxicidad , Antígeno Nuclear de Célula en Proliferación/metabolismo , Desarrollo Embrionario/efectos de los fármacos , Tubo Neural/efectos de los fármacos , Tubo Neural/embriología , Caspasa 3/metabolismo , Caspasa 3/genética , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacosRESUMEN
The current study compared the effects of incorporated exposure to arsenic trioxide (As) and zinc oxide nanoparticles (ZnONPs) on male reproductive hormones, oxidative stress, and inflammatory biomarkers in adult rats to each metal alone. A defensive trial with gallic acid (GA) has also been studied. A total of 60 adult male Sprague Dawley rats were categorized into six groups: control, GA (20 mg/kg), ZnONPs (100 mg/kg), As (8 mg/kg), ZnONPs with As, and GA concurrently with ZnONPs and As at the same previous doses. The regimens were applied for 60 days in sequence. Current findings showed significant weight loss in all study groups, with testicular weights significantly decreased in the As and combined groups. Testosterone, follicular stimulating hormone, and luteinizing hormone serum levels were also considerably reduced, while serum levels of estradiol increased. Inducible nitric oxide synthase (iNOS) immunoexpression was significantly upregulated while proliferating cell nuclear antigen (PCNA) was downregulated. Moreover, there was a significant elevation of testicular malondialdehyde, reduction of testicular superoxide dismutase, and glutathione peroxidase with disruptive testes, prostate glands, and seminal vesicle alterations in all experimental groups with marked changes in the combined group. Additionally, the present results revealed the protective effects of GA on ZnONPs and As adverse alterations in rats. GA enhanced sperm picture, oxidant status, and hormonal profile. Also, it modulates iNOS and PCNA immunoexpression and recovers the histoarchitecture of the testes, prostate glands, and seminal vesicles. Ultimately, GA may be a promising safeguarding agent against ZnONPs and As-induced disturbances to reproductive parameters.
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BACKGROUND AND OBJECTIVE: Chronic rhinosinusitis is a common inflammatory disorder in sinonasal mucosa that could be developed with or without nasal polyps. Cellular proliferation is suggested as a possible mechanism of nasal polyp development. However, conducted studies in this context are limited. So, the present study's aim is the comparison of Proliferating cell nuclear antigen (PCNA) expression in nasal polyps and chronic rhinosinusitis. MATERIALS AND METHODS: In this cross-sectional study, 70 nasal polyp and 60 chronic rhinosinusitis samples from patients referred to Mostafa Khomeini Hospital, Tehran from 2017 to 2022 were immunohistochemically stained by PCNA marker. The percentage of PCNA nuclear expression was determined in two groups and its association with the type of pathological lesion and the patient's age and sex was analyzed by SPSS statistic software version 24 statistical software (IBM Statistics, USA). RESULTS: The mean expression of PCNA in nasal polyp and chronic rhinosinusitis samples was 16.55%⯱â¯13.66 and 17.58%⯱â¯12.68 respectively (ranging from 0 to 57% in both groups) however, there was no significant statistical difference between the two groups (pâ¯=â¯0.479). No relationship was found between PCNA expression with age and sex in none of the chronic rhinosinusitis and nasal polyp groups. CONCLUSION: Proliferative activity of the nasal epithelial cell is similar in chronic rhinosinusitis with and without nasal polyps and it is considered that the increase of epithelial cell proliferative activity probably has no role in nasal polyp development in patients with chronic rhinosinusitis.
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In recent years, diseases such as age-related macular degeneration and retinal pigment degeneration caused by excessive exposure to short-wavelength visible light have become significant concerns. With the aim of quantitatively evaluating the toxicity of short-wavelength light, proliferating cell nuclear antigen (PCNA) accumulation at the irradiation site was investigated using live cell imaging techniques to irradiate individual living cells with short-wavelength laser light. By examining the dependency of PCNA accumulation on the irradiation site within the cells and their cell cycle, it was observed that PCNA accumulation occurred only when the cell nucleus of cells in the S phase of the cell cycle was irradiated. We investigated the accumulation of PCNA at the laser irradiation site using laser light at wavelengths of 405 nm and 375 nm, with intensities ranging from 0.5 µW to 9.0 µW. The results confirmed an increase in PCNA accumulation with increasing intensity, and a higher accumulation was observed with laser light irradiation at a wavelength of 375 nm compared to 405 nm. By comparing the PCNA accumulation and 24 h cell viability, we demonstrated the feasibility of quantitatively assessing laser light toxicity through the measurement of PCNA accumulation.
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Lysozyme like 4 (LYZL4), lysozyme like 6 (LYZL6) and proliferating cell nuclear antigen (PCNA) are implicated in the regulation of testicular function, but there was no research reported available on the expression patterns of LYZL4, LYZL6 and PCNA genes at different developmental stages of yak testes. In this study, we used the qRT-PCR, western blotting and immunohistochemistry estimated the LYZL4, LYZL6 and PCNA gene expression and protein lo-calization at different developmental stages of yak testes. The qPCR results showed that the mRNA expression of LYZL4, LYZL6 and PCNA genes significantly increased with age in the testes of yaks. Western blot results showed that the protein abundance of LYZL4, LYZL6 and PCNA in yak testes was significantly higher after puberty than before puberty. Furthermore, the results of immunohistochemistry indicated that LYZL4, LYZL6 and PCNA may be involved in the regulation of spermatogonia proliferation and Leydig cell function in immature testis. In adult yak testes, LYZL4, LYZL6 and PCNA may involve in the development of round spermatids and primary spermatocytes during testicular development. Our results indicated that LYZL4, LYZL6 and PCNA may be involved in the development of Sertoli cells, Leydig cells and gonocytes in yak testes.
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Antígeno Nuclear de Célula en Proliferación , Testículo , Animales , Masculino , Testículo/crecimiento & desarrollo , Testículo/metabolismo , Antígeno Nuclear de Célula en Proliferación/genética , Antígeno Nuclear de Célula en Proliferación/metabolismo , Bovinos/genética , Bovinos/crecimiento & desarrollo , Regulación del Desarrollo de la Expresión Génica , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Envejecimiento , Células Intersticiales del Testículo/metabolismoRESUMEN
Alendronate sodium (ALS) is a nitrogen-containing bisphosphonate used for the treatment of different bone disorders. However, its adverse effect on oral soft tissue has been detected. Rutin (RUT) is natural flavonoid with antioxidant and anti-inflammatory properties. This work aimed to investigate the possible effect of ALS on the tongue of adult male albino rats and to evaluate the possible protective role of RUT. Forty adult male albino rats were equally divided into four groups: group I (control), group II (RUT): Received RUT 50 mg/kg, group III (ALS): Received ALS 1 mg/kg, group IV (ALS+RUT): Received ALS and RUT with the same doses as pervious groups. The drugs were given once daily for 5 weeks. Tongue specimens were taken and processed for light and scanning electron microscopic inspection. ALS treated group revealed structural changes in the tongue in the form of decrease in the height of the filiform papillae with blunt ends, marked atrophy in some papillae with areas of focal loss, loss of some epithelial cells, pyknotic nuclei and cytoplasmic vacuoles in some epithelial cells. The lamina propria showed inflammatory cellular infiltration with congested blood vessels. Statistically, there were highly significant decrease in the number of proliferating cell nuclear antigen immunopositive cells, area percentage of Bcl-2 immunoexpression and highly significant increase in the collagen content compared to control group. Administration of RUT with ALS minimizes these changes. RUT protected the rat tongue against the histological and immunohistochemical changes induced by ALS through its antioxidant and anti-inflammatory properties.
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BACKGROUND: Radiotherapy in head and neck cancer management causes degeneration of the salivary glands (SG). This study was designed to determine the potential of gingival mesenchymal stem cells (GMSCs) as a cell-based therapy to regenerate irradiated parotid SG tissues and restore their function using a murine model. METHODS: Cultured isolated cells from gingival tissues of 4 healthy guinea pigs at passage 3 were characterized as GMSCSs using flow cytometry for surface markers and multilineage differentiation capacity. Twenty-one Guinea pigs were equally divided into three groups: Group I/Test, received single local irradiation of 15 Gy to the head and neck field followed by intravenous injection of labeled GMSCs, Group II/Positive control, which received the same irradiation dose followed by injection of phosphate buffer solution (PBS), and Group III/Negative control, received (PBS) injection only. Body weight and salivary flow rate (SFR) were measured at baseline, 11 days, 8-, 13- and 16-weeks post-irradiation. At 16 weeks, parotid glands were harvested for assessment of gland weight and histological and immunohistochemical analysis. RESULTS: The injected GMSCs homed to degenerated glands, with subsequent restoration of the normal gland histological acinar and tubular structure associated with a significant increase in cell proliferation and reduction in apoptotic activity. Subsequently, a significant increase in body weight and SFR, as well as an increase in gland weight at 16 weeks in comparison with the irradiated non-treated group were observed. CONCLUSION: The study provided a new potential therapeutic strategy for the treatment of xerostomia by re-engineering radiated SG using GMSCs.
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Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Ratones , Animales , Cobayas , Modelos Animales de Enfermedad , Glándulas Salivales , Inyecciones Intravenosas , Peso CorporalRESUMEN
In this study, the impact of chitosan (CS) and maitake (GF) nanoparticles towards the renal toxicity induced by Ehrlich ascites carcinoma (EAC) in vivo model was conducted. Besides benchmark negative control group, EAC model was constructed by intraperitoneal injection (i.p.) of 2.5 × 106 cells. Alongside positive control, two groups of EAC-bearing mice received 100 mg/kg of CS and GF nanoparticles/body weight daily for 14 days. The kidney function was conducted by measuring urea, creatinine, ions, (anti)/oxidative parameters and DNA damage. Also, measuring immunoreactivity of P53, proliferating cell nuclear antigen (PCNA), and B-cell lymphoma 2 (Bcl-2) and apoptosis protein. The outcomes illustrated notable kidney toxicity, which indicated by elevations in urea, creatinine, oxidative stress, DNA damage and induction of apoptosis. These events were supported by the drastic alteration in kidney structure through histological examination. Administration of CS and GF nanoparticles was able to enhance the antioxidant power, which further reduced oxidative damage, DNA injury, and apoptosis. These results indicated the protective and therapeutic role of biogenic chitosan and maitake nanoparticles against nephrotoxicity.
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Carcinoma de Ehrlich , Quitosano , Grifola , Animales , Ratones , Ascitis/metabolismo , Quitosano/uso terapéutico , Carcinoma de Ehrlich/tratamiento farmacológico , Carcinoma de Ehrlich/patología , Creatinina , Daño del ADN , Urea , ApoptosisRESUMEN
Arbutin is utilized in traditional remedies to cure numerous syndromes because of its anti-microbial, antioxidant, and anti-inflammatory properties. This study aimed to evaluate chemopreventive effects of arbutin on azoxymethane (AOM)-induced colon aberrant crypt foci (ACF) in rats. Five groups of rats were used: normal control group (rats injected hypodermically with sterile phosphate-buffered saline once per week for two weeks) and groups 2-5, which were subcutaneously inoculated with 15 mg/kg AOM once a week for two weeks. AOM control and 5-fluorouracil (5-FU) control groups were fed 10% Tween orally daily for 8 weeks using a feeding tube. The treated groups were fed 30 and 60 mg/kg arbutin every day for 2 months. ACF from the AOM control group had aberrant nuclei in addition to multilayered cells and an absence of goblet cells. The negative control group displayed spherical cells and nuclei in basal positions. Histological examination revealed a reduced number of AFC cells from colon tissues of the 5-FU reference group. Arbutin-fed animals showed down-regulation of proliferating cell nuclear antigen (PCNA) and up-regulation of Bax protein compared to AOM control. Rats fed with arbutin displayed a significant increase of superoxide dismutase (SOD) and catalase (CAT) activities in colon tissue homogenates compared to the AOM control group. In conclusion, arbutin showed therapeutic effects against colorectal cancer, explained by its ability to significantly decrease ACF, down-regulate PCNA protein, and up-regulate Bax protein. In addition, arbutin significantly increased SOD and CAT, and decreased malondialdehyde (MDA) levels, which might be due to its anti-proliferative and antioxidant properties.
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Bladder cancer (BC) is one of the most common cancers worldwide. Although the treatment and survival rate of BC are being improved, the risk factors and the underlying mechanisms causing BC are incompletely understood. Squalene monooxygenase (SQLE) has been associated with the occurrence and development of multiple cancers but whether it contributes to BC development is unclear. In this study, we performed bioinformatics analysis on paired BC and adjacent non-cancerous tissues and found that SQLE expression is significantly upregulated in BC samples. Knockdown of SQLE impairs viability, induces apoptosis, and inhibits the migration and invasion of BC cells. RNA-seq data reveals that SQLE deficiency leads to dysregulated expression of genes regulating proliferation, migration, and apoptosis. Mass spectrometry-directed interactome screening identifies proliferating cell nuclear antigen (PCNA) as an SQLE-interacting protein and overexpression of PCNA partially rescues the impaired viability, migration, and invasion of BC cells caused by SQLE knockdown. In addition, we performed xenograft assays and confirmed that SQLE deficiency inhibits BC growth in vivo. In conclusion, these data suggest that SQLE promotes BC development and SQLE inhibition may be therapeutically useful in BC treatment.
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Escualeno-Monooxigenasa , Neoplasias de la Vejiga Urinaria , Humanos , Antígeno Nuclear de Célula en Proliferación/genética , Escualeno-Monooxigenasa/genética , Neoplasias de la Vejiga Urinaria/genética , Apoptosis/genética , Biología ComputacionalRESUMEN
A common approach to cancer therapy is the combination of a natural product with chemotherapy to overcome sustained cell proliferation and chemotherapy resistance obstacles. Diosgenin (DG) is a phytosteroidal saponin that is naturally present in a vast number of plants and has been shown to exert anti-cancer activities against several tumor cells. Herein, we assessed the chemo-modulatory effects of DG on volasertib (Vola) as a polo-like kinase 1 (PLK1) inhibitor and doxorubicin (DOX) in hepatocellular carcinoma (HCC) cell lines. DOX and Vola were applied to two human HCC cell lines (HepG2 and Huh-7) alone or in combination with DG. The cell viability was determined, and gene expressions of PLK1, PCNA, P53, caspase-3, and PARP1 were evaluated by RT-qPCR. Moreover, apoptosis induction was determined by measuring active caspase-3 level using ELISA method. DG enhanced the anticancer effects of Vola and DOX. Moreover, DG enhanced Vola- and DOX-induced cell death by downregulating the expressions of PLK1 and PCNA, elevating the expressions of P53 and active caspase-3. DG showed promising chemo-modulatory effects to Vola and DOX against HCC that may be attributed partly to the downregulation of PLK1 and PCNA, upregulation of tumor suppressor protein P53, and apoptosis induction. Thus, DG combination with chemotherapy may be a promising treatment approach for HCC.
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Apoptosis , Carcinoma Hepatocelular , Diosgenina , Doxorrubicina , Neoplasias Hepáticas , Quinasa Tipo Polo 1 , Humanos , Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Apoptosis/efectos de los fármacos , Carcinoma Hepatocelular/tratamiento farmacológico , Caspasa 3/metabolismo , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Diosgenina/farmacología , Diosgenina/análogos & derivados , Doxorrubicina/farmacología , Sinergismo Farmacológico , Células Hep G2 , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Pteridinas/farmacología , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
O6-methylguanine DNA methyl transferase (MGMT) is a significant vehicle for the cellular clearance of alkyl lesions, particularly the methyl group of the O-6 and O-4 positions of guanine and thymine, respectively. Many publications have studied the correlation between polymorphisms in MGMT and susceptibility to various cancers. In the present study, we investigated the consequence of L84F, common single-nucleotide polymorphism, K125E, site-specific mutagenesis, and L84F/K125E on conformation, stability, and behavior of MGMT in the free form and interaction with proliferating cell nuclear antigen (PCNA) and DNA as partners in the biochemical network by using molecular dynamics simulation method. Our results showed that all free variants of MGMT differed from the native form. However, among all free variants of MGMT, the L84F/K125E variant exhibited similar properties compared with the wild-type. In contrast, in complex modes, only amino acid residues of the L84F variant are involved in the interactions with PCNA and DNA somewhat differently relative to the wild-type. Furthermore, L84F SNP showed the highest binding free energy compared to other variants and native forms. These alterations in the amino acids and binding free energy of L84F relative to the native are the reasons for changing its region connection compared to the native form. Therefore, we propose conducting further investigations into the impact of inhibitors or chemotherapeutic agents to assess their effectiveness on MGMT variants compared to the wild-type, aiming to reduce the cost of cancer treatment that will depend on inhibiting native MGMT protein.Communicated by Ramaswamy H. Sarma.
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Objective To explore the mechanism by which CD137 signal regulates the aging of vas-cular smooth muscle cells(VSMCs).Methods Thirty 8-week-old male C57BL/6J mice were ran-domly divided into a young group(8 weeks old)and an aged group(80 weeks old),with 30 mice in each group.After corresponding periods of feeding,the mice were euthanized,and the plasma and aortic blood vessels were isolated.In the cell experiments,normal VSMCs were divided into a control group,bleomycin(BLM)group,combined agonist group,and combined inhibitor group.The cellular senescence level of VSMCs was assessed using a cellular senescence β-galactosidase staining kit.Western blotting and PCR were employed to examine the expression of senescence-related proteins in tissues and cells,while ELISA was utilized to measure the expression of senes-cence-related inflammatory factors.Results The expression of CD137 and γ-H2AX in the aorta was significantly higher,while that of PCNA was obviously lower in the aged group than the young group(P＜0.05).The plasma level of CD137 was notably higher in the aged group than the young group(154.0±4.1 pg/ml vs 98.0±2.3 pg/ml,P＜0.05).Compared with the normal control group,there were significantly more aged VSMCs in the BLM group(P＜0.05).While,treatment of combined agonist resulted in larger amount of aged VSMCs when compared with the BLM group(P＜0.05),which was reversed by combined inhibitor treatment(P＜0.05).The levels of TNF-α,IL-6 and IL-1β were significantly elevated in the BLM group than the normal control group(P＜0.05).The combined agonist group had even higher levels of TNF-α,IL-6,and IL-1βthan the BLM group(P＜0.05),but the levels were decreased in the combined inhibitor group(P＜0.05).Compared with the normal control group,the expression of Bcl-2,γ-H2AX,P53,and P21 were significantly increased in the BLM group,combined agonist group,and combined inhibi-tor group,while that of PCNA was significantly decreased(P＜0.05).Compared with the BLM group,the expression of P53 and P21 in the combined agonist group showed an increase(P＜0.05),and the expression of P53 was significantly decreased in the combined inhibitor group(P＜0.05).Conclusion CD137 signal regulates the P53/P21 pathway to promote VSMC aging.
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Objective:To explore the relationship between the expressions of P21,P27 and proliferating cell nuclear antigen(PCNA)in glomerular mesangial tissue and poor renal prognosis in patients with immunoglobulin A(IgA)nephropathy.Methods:A total of 145 patients with IgA nephropathy treated in Xiaogan Central Hospital from April 2017 to August 2019 were selected as the research object.The expressions of P21,P27 and PCNA in glomerular mesangial tissue were detected by immunohistochemistry.All patients were followed up for 24 months,and the prognosis were counted.The expressions of P21,P27 and PCNA in glomerular mesangial tissue of patients with different prognosis were compared and the influencing factors of poor prognosis in patients with IgA nephropathy were analyzed by Logistic regression analysis.Results:The expression rates of P21,P27 and PCNA positive cells in glomerular mesangial tissue of patients with IgA nephropathy were(38.69±6.83)%,(55.94±8.08)%,(33.47±5.72)%,respectively.The incidence rete of poor prognosis in patients with IgA nephropathy was 17.24%,and the expression rates of P21 and PCNA positive cells in glomerular mesangial tissue of patients with poor prognosis were higher than those in good prognosis group(P<0.05),while the expression rate of P27 positive cells was lower than that in good prognosis group(P<0.05).Logistic multiple regression analysis showed that elevated diastolic blood pressure,increased 24 h proteinuria,mesangial cell proliferation,segmental glomerulosclerosis,renal tubular atrophy/interstitial fibrosis,crescentic body,increased expression rates of P21 and PCNA positive cells and decreased expression rate of P27 positive cells were all risk factors affecting the poor prognosis of patients with IgA nephropathy(P<0.05).Conclusion:There are positive expressions of P21,P27 and PCNA in glomerular mesangial tissue of IgA nephropathy.The expression rates of P21 and PCNA positive cells in glomerular mesangial tissue of of patients with poor prognosis of IgA nephropathy are higher than those with good prognosis,while the expression rate of P27 protein positive cells is lower than those with good prognosis,which are risk factors for poor prognosis of patients with IgA nephropathy.
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Proliferating cell nuclear antigen (PCNA) is a homo-trimeric clamp complex that serves as the molecular hub for various DNA transactions, including DNA synthesis and post-replicative mismatch repair. Its timely loading and unloading are critical for genome stability. PCNA loading is catalyzed by Replication factor C (RFC) and the Ctf18 RFC-like complex (Ctf18-RLC), and its unloading is catalyzed by Atad5/Elg1-RLC. However, RFC, Ctf18-RLC, and even some subcomplexes of their shared subunits are capable of unloading PCNA in vitro, leaving an ambiguity in the division of labor in eukaryotic clamp dynamics. By using a system that specifically detects PCNA unloading, we show here that Atad5-RLC, which accounts for only approximately 3% of RFC/RLCs, nevertheless provides the major PCNA unloading activity in Xenopus egg extracts. RFC and Ctf18-RLC each account for approximately 40% of RFC/RLCs, while immunodepletion of neither Rfc1 nor Ctf18 detectably affects the rate of PCNA unloading in our system. PCNA unloading is dependent on the ATP-binding motif of Atad5, independent of nicks on DNA and chromatin assembly, and inhibited effectively by PCNA-interacting peptides. These results support a model in which Atad5-RLC preferentially unloads DNA-bound PCNA molecules that are free from their interactors.