Clinical significance of p27 Kip1 expression in advanced ovarian cancer

Background: Ovarian cancer is the most common gynecological malignancy. In patients with advanced ovarian cancer, some biological parameters have prognostic implementations. P27kip1 is an inhibitor of a cycline-dependent kinase, its loss, can contribute to tumor progression. Objective: This study aimed to examine the importance of P27KIP1 protein in predicting the prognosis and response to neoadjuvant chemotherapy in patients with advanced ovarian epithelial cancer and to compare the outcomes of immunohistochemistry with Quantitative Real-time PCR. Patients and methods: We have studied P27KIP1expression by both immunohistochemistry and Quantitative Realtime PCR from 88 patients with advanced ovarian carcinomas undergone radical debulking surgery and received Paclitaxel followed by Cisplatin every 3 weeks for a total of 6 cycles. We also studied their association with both chemotherapy response and patient survival. Results: Nuclear expression of p27KIP1 protein was intense in 86 normal ovarian tissues and 42 of 88 carcinomas. The P27kip1mRNA expression level by qRT-PCR was very low in ovarian cancer tissues relative to its adjacent normal tissues. The results were statistically significant by both methods of determination. p27KIP1 expression was significantly related to good prognostic parameters as low stage tumors, differentiated tumors, absence of ascites, residual disease < 2 cm, and response to chemotherapy but not with histopathological type in case of determination by immunohistochemistry. Comparison of P27kip1 by both immunohistochemistry and qRTPCR with different prognostic parameters revealed no significant difference between both methods in the assessment of these parameters. In 4 years of follow-up, 20.5% of patients were alive without evidence of disease. 6.8% were alive with disease. The disease-related four -year survival rate for the whole group was 28.2%. In multivariate analysis, residual disease, histological type, tumor differentiation, ascites was of independent prognostic significance. Conclusion: In ovarian cancer, patients with loss of p27KIP1 expression are at a greater likelihood of disease progression, p27KIP1 may be used as a molecular marker to predict response to chemotherapy and prognosis. Both immunohistochemistry and qRT-PCR have equal reliability in the determination of p27 KIP1

Skp2 inhibitor SKPin C1 decreased viability and proliferation of multiple myeloma cells and induced apoptosis

Multiple myeloma (MM) is a malignant neoplasm of plasma, and exhibits several harmful effects including osteolytic injuries, hypercalcemia, and immune dysfunction. Many patients with MM succumb to the underlying malignancy. An S-phase kinase-related protein 2 (Skp2) inhibitor, designated SKPin C1, has been developed and confirmed to have an inhibitory effect on metastatic melanoma cells. This study aimed to determine the effect of SKPin C1 on MM. Normal B lymphocytes, THP-1 cells, and MM U266 and RPMI 8226 cells were exposed to various dosages of SKPin C1 for 48 h. Cell proliferation was determined by MTT, EdU staining, and cell cycle assays. Western blot assays were performed to assess intracellular protein levels of Skp2, p27, and cleaved caspase-3. The amount of ubiquitin attached to p27 was determined using an immunoprecipitation assay. The viability of U266 and RPMI 8226 cells was significantly inhibited by 10 μM SKPin C1 and the inhibitory effect was enhanced with increasing doses of SKPin C1. In contrast, 50 μM SKPin C1 only marginally decreased viability of normal B lymphocytes in 12 h. Skp2 and p27 expression in U266 and RPMI 8226 cells was higher and lower, respectively, than that in the normal B lymphocytes. Treatment with SKPin C1 or Skp2 knockdown increased p27 protein levels in U266 and RPMI 8226 cells by preventing p27 from being ubiquitinated, which slowed the cell cycle, inhibited cell proliferation, and triggered apoptosis. Therefore, this study suggested SKPin C1 as a potent inhibitor against aberrant proliferation and immortalization of MM.

Low p27kip1 expression in head and neck squamous cell carcinoma: association with risk factors and adverse outcomes

Background: Squamous cell carcinoma (SCC) of head and neck is highly prevalent in South-asian countries, owing to high consumption of areca nut/gutka and chewing tobacco. p27kip1 is a tumor suppressor gene, thought to be downregulated in oral squamous cell carcinoma. Therefore, in the present study we used immunohistochemical analysis to investigate an association between low p27kip1 expression in SCC of the head and neck and adverse outcomes/risk factors. Methods: Total 105 cases of SCC of head and neck excision specimens were selected from records of pathology department archives that underwent surgeries at Liaquat National hospital, Karachi from January 2008 till December 2013. Clinical and pathologic characteristics of patients were evaluated and p27kip1 immunohistochemistry was applied on tumor blocks. Results: In our study, low expression of p27kip1 in SCC of head and neck was seen in 39(37.1%) cases while 66(62. 9%) of the cases showed high expression for p27kip1. Significant association of p27kip1 expression with pan/gutka usage (p = 0.004), and recurrence (p = 0.001) was noted; however, no significant association of p27kip1 expression with other clinicopathologic features was seen. Multivariate binary logistic regression showed cases with history of pan/gutka usage were more likely to show low p27kip1 expression. Similarly, we also found that recurrence was more likely to develop in patients with low expression of p27kip1 in comparison to cases showing high p27kip1 expression. Conclusion: Loss of p27kip1 expression is a significant event involved in the pathogenesis of SCC head and neck especially that of oral cavity. Significant association of gutka/areca nut with low p27kip1 expression in our study suggests that loss p27kip1 expression is a major event involved in areca nut induced SCC of head and neck in this part of the world; however, more large scale molecular based studies are required to validate this observation. Moreover, significant association of low p27kip1 expression with tumor recurrence suggests its importance as a prognostic biomarker in SCC of head and neck (AU)

MicroRNA-186 targets SKP2 to induce p27(Kip1)-mediated pituitary tumor cell cycle deregulation and modulate cell proliferation

Pituitary tumors are usually benign but can occasionally exhibit hormonal and proliferative behaviors. Dysregulation of the G1/S restriction point largely contributes to the over-proliferation of pituitary tumor cells. F-box protein S-phase kinase-interacting protein-2 (SKP2) reportedly targets and inhibits the expression of p27(Kip1), a well-known negative regulator of G1 cell cycle progression. In this study, SKP2 expression was found to be upregulated while p27(Kip1) expression was determined to be downregulated in rat and human pituitary tumor cells. Furthermore, SKP2 knockdown induced upregulation of p27(Kip1) and cell growth inhibition in rat and human pituitary tumor cells, while SKP2overexpression elicited opposite effects on p27(Kip1) expression and cell growth. The expression of microRNA-186 (miR-186) was reported to be reduced in pituitary tumors. Online tools predicted SKP2 to be a direct downstream target of miR-186, which was further confirmed by luciferase reporter gene assays. Moreover, miR-186 could modulate the cell proliferation and p27(Kip1)-mediated cell cycle alternation of rat and human pituitary tumor cells through SKP2. As further confirmation of these findings, miR-186 and p27(Kip1) expression were downregulated, while SKP2 expression was upregulated in human pituitary tumor tissue samples; thus, SKP2 expression negatively correlated with miR-186 and p27(Kip1) expression. In contrast, miR-186 expression positively associated with p27(Kip1) expression. Taken together, we discovered a novel mechanism by which miR-186/SKP2 axis modulates pituitary tumor cell proliferation through p27(Kip1)-mediated cell cycle alternation.

Cardiac Hypertrophy is Positively Regulated by MicroRNA‑24 in Rats / 中华医学杂志(英文版)

<p><b>Background</b>MicroRNA-24 (miR-24) plays an important role in heart failure by reducing the efficiency of myocardial excitation-contraction coupling. Prolonged cardiac hypertrophy may lead to heart failure, but little is known about the role of miR-24 in cardiac hypertrophy. This study aimed to preliminarily investigate the function of miR-24 and its mechanisms in cardiac hypertrophy.</p><p><b>Methods</b>Twelve Sprague-Dawley rats with a body weight of 50 ± 5 g were recruited and randomly divided into two groups: a transverse aortic constriction (TAC) group and a sham surgery group. Hypertrophy index was measured and calculated by echocardiography and hematoxylin and eosin staining. TargetScans algorithm-based prediction was used to search for the targets of miR-24, which was subsequently confirmed by a real-time polymerase chain reaction and luciferase assay. Immunofluorescence labeling was used to measure the cell surface area, and H-leucine incorporation was used to detect the synthesis of total protein in neonatal rat cardiac myocytes (NRCMs) with the overexpression of miR-24. In addition, flow cytometry was performed to observe the alteration in the cell cycle. Statistical analysis was carried out with GraphPad Prism v5.0 and SPSS 19.0. A two-sided P < 0.05 was considered as the threshold for significance.</p><p><b>Results</b>The expression of miR-24 was abnormally increased in TAC rat cardiac tissue (t = -2.938, P < 0.05). TargetScans algorithm-based prediction demonstrated that CDKN1B (p27, Kip1), a cell cycle regulator, was a putative target of miR-24, and was confirmed by luciferase assay. The expression of p27 was decreased in TAC rat cardiac tissue (t = 2.896, P < 0.05). The overexpression of miR-24 in NRCMs led to the decreased expression of p27 (t = 4.400, P < 0.01), and decreased G0/G1 arrest in cell cycle and cardiomyocyte hypertrophy.</p><p><b>Conclusion</b>MiR-24 promotes cardiac hypertrophy partly by affecting the cell cycle through down-regulation of p27 expression.</p>

fundamental role played by cell cycle proteins in controlling cell proliferation in chronic hepatitis C virus infection

Background: examining the alteration of cell cycle genes in early hepatitis C virus [HCV] found that altered expression of mitotic checkpoint genes, MAD2L1, KNTC1, CDC16 and CDC34, KNTC1 known as "rough deal protein" [ROD] is part of a complex involved in elaborating an inhibitory signal due to improper chromosomal aligment during cell division

Aim of the work: attempt for the identification of proteins [genes], which act as predictive factors to identify patients with high risk of cell transformation and HCC development

Patients and Methods: fifty three patients with chronic HCV infection, age ranged between 18 and 58 years, time of assessment was before starting therapy of hepatitis C at the National Hepatology and Tropical Medicine Research Institute. Ten healthy individuals were included to serve as controls. All the patients and controls were subjected to the following: history, clinical examination, abdominal ultrasonography, and collection of blood samples for routine laboratory investigation; CBCs. Liver biopsy was done to all patients and controls, patients revealed mild fibrosis [Metavir fibrosis scores from F1 to F3]. Also, we used freshly frozen liver biopsies mRNA levels with perspective protein levels of four genes: P27, P15, KNTC1, MAD2L1

Results: significant association of P27, P15, KNTC1 and MAD2L-1 with the progression of liver fibrosis in chronic HCV liver biopsy was found

Conclusion: there is altered gene expression in HCV-associated liver disease

Recommendations: The emerging interest of hepatologists in the influence of genetic factors in HCV. Evaluation of the expression of key proteins related to the cell cycle and apoptosis in chronically infected patients with HCV would be of significance to understand disease pathogenesis, and will help in identifying novel prognostic indicators

Correlation between cyclin-dependent kinase inhibitor p27kip1 and trastuzumab-resistance in gastric cancer / 中南大学学报(医学版)

OBJECTIVE@#To investigate the correlation between cyclin-dependent kinase inhibitor p27kip1 and trastuzumab-resistance in gastric cancer.
@*METHODS@#We selected HER2-overexpressed human gastric cancer cell line NCI-N87 to establish trastuzumab-resistant NCI-N87/TR cell line by stepwise exposure to different doses of trastuzumab. The 50% inhibitory concentration (IC(50)) of trastuzumab and resistance index (RI) were calculated or analyzed by MTT assay. The expression levels of cdk2 and p27kip1 were detected by Western blot. After the treatment with cdk2 inhibitor (Purvalanol A), the expression levels of relevant proteins in NCI-N87/TR cells were detected by Western blot, and the sensitivity to trastuzumab was analyzed by MTT assay. 
@*RESULTS@#Compared with NCI-N87 cells, the expression of cdk2 was significantly increased in NCI-N87/TR cells (P<0.001), while the expression of p27kip1 showed a significant decrease (P<0.001). Restoration of the p27kip1 protein expression by cdk2 inhibitor (Purvalanol A) increased the sensitivity of NCI-N87/TR to trastuzumab.
@*CONCLUSION@#Down-regulation of p27kip1 might be a mechanism for triggering trastuzumab resistance to gastric cancer cell line NCI-N87.

Effect of Foxo3a gene over-expression on the development of rat ovarian granulose cells and in prevention of cisplatin-induced ovarian damage in rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the effect of Foxo3a gene over-expression on the development of rat ovarian granulosa cells and in prevention of cisplatin-induced ovarian damage in rats.</p><p><b>METHODS</b>Rat ovarian granulose cells released mechanically from the ovaries were cultured in vitro and identified with HE staining and immunohistochemical staining for FSHR. A recombinant adenovirus carrying Foxo3a gene was constructed for infecting the granulose cells, and the cell growth and expressions of cyclin D1, p27, Bax, and Bim were detected; the cell apoptosis and cell cycle changes were detected using Hoechst/PI 33342 staining and flow cytometry, respectively. The transfected cells were challenged with cisplatin and the cell apoptosis was detected with flow cytometry.</p><p><b>RESULTS</b>Over 90% of the cultured cells survived and contained more than 95% ovarian granulose cells. Infection of the cells with the recombinant adenovirus resulted in over-expressions of Foxo3a at the mRNA and protein levels at 36 h and 48 h after the infection, respectively. The infected cells showed suppressed proliferation, increased apoptotic rate and cell cycle arrest in G1 phase with increased expressions of Bim, p27, and cyclin D1 but without significant changes in Bax expression. Cisplatin exposure caused a significantly higher apoptosis rate in the infected cells than in the control cells.</p><p><b>CONCLUSION</b>Over-expression of Foxo3a gene can promote granulose cell apoptosis by increasing Bim expression and cause cell cycle arrest in G1 phase by increasing cyclin D1 and p27 expressions, but can not prevent the toxic effects of cisplatin on ovarian granulosa cells.</p>

The Relevance of Women's Diseases, Jun Activation-domain Binding Protein 1 (JAB1) and p27(kip1)

The Jun activation-domain binding protein 1 (Jab1) recognize a potential coactivator of activator protein 1 (AP-1) such as c-fos, c-jun transcription factor and the fifth subunit of the COP9 signalosome complex. Also, Jab1 activate the c-jun gene resulted cell proliferation. Not only a powerful tumor suppressor but also regulator of apoptosis negative cdk inhibitor p27(kip1) are involved in the cell cycle. This is Jab1 and p27(kip1) interact with each other, Jab1 accelerate p27(kip1) from nuclear to cytoplasm through ubiquitin/proteasome pathway. However, information about the relationship between Jab1 and p27(kip1) is not known much. Taken together, the results of this study identify function and structure of Jab1 and p27(kip1) were described in a recent article on the basis of relevant. Besides Jab1 and p27(kip1) will organize the relationship between the disease and women.

Do Helper T Cell Subtypes in Lymphocytic Thyroiditis Play a Role in the Antitumor Effect?

BACKGROUND: Papillary thyroid carcinoma (PTC) is frequently accompanied by lymphocytic thyroiditis (LT). Some reports claim that Hashimoto's thyroiditis (the clinical form of LT) enhances the likelihood of PTC; however, others suggest that LT has antitumor activity. This study was aimed to find out the relationship between the patterns of helper T cell (Th) cytokines in thyroid tissue of PTC with or without LT and the clinicopathological manifestation of PTC. METHODS: Fresh surgical samples of PTC with (13 cases) or without (10 cases) LT were used. The prognostic parameters (tumor size, extra-thyroidal extension of PTC, and lymph node metastasis) were analyzed. The mRNA levels of two subtypes of Th cytokines, Th1 (tumor necrosis factor α [TNF-α], interferon γ [IFN-γ ], and interleukin [IL] 2) and Th2 (IL-4 and IL-10), were analyzed. Because most PTC cases were microcarcinomas and recent cases without clinical follow-up, negative or faint p27 immunoreactivity was used as a surrogate marker for lymph node metastasis. RESULTS: PTC with LT cases showed significantly higher expression of TNF-α (p = .043), IFN-γ (p < .010), IL-4 (p = .015) than those without LT cases. Although the data were not statistically significant, all analyzed cytokines (except for IL-4) were highly expressed in the cases with higher expression of p27 surrogate marker. CONCLUSIONS: These results indicate that mixed Th1 (TNF-α, IFN-γ , and IL-2) and Th2 (IL-10) immunity might play a role in the antitumor effect in terms of lymph node metastasis.

Effects of Rapamycin and Rapamycin-loaded Poly(lactic-co-glycolic)Acid Nanoparticles on Apoptosis and Expression of bcl-2 and p27(kip1) Proteins of Human Umbilical Arterial Vascular Smooth Muscle Cell / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investgate the effects of rapamycin(RPM)and RPM-loaded poly(lactic-co-glycolic)acid(PLGA)nanoparticles(NPs)on the apoptosis of human umbilical arterial vascular smooth muscle cells(HUASMCs)in vitro and expression of bcl-2 and p27(kip1) protein.</p><p><b>METHODS</b>HUASMCs were cultured in vitro and divided to RPM and RPM-PLGA-NPs groups treated at 3 different concentration by 12 and 24 hours,with M231-smooth muscle growth supplements medium and null-PLGA-NPs treated groups as controlled. The apoptosis of HUASMCs was determined by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling staining and flow cytometry. The expressions of bcl-2 and p27(kip1) were detected by streptacidin/peroxidase immunohistochemical method. The effect on cellular proliferation was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromidecolorimetry.</p><p><b>RESULTS</b>The proliferation of HUASMCs was inhibited by RPM and RPM-PLGA-NPs in a dose-dependent manner. DNA electrophoresis showed DNA ladder in RPM and RPM-PLGA-NPs groups and classical scalar strips in control groups. The apoptotic indexes of RPM 100 ng/ml group and RPM-PLGA-NPs 500 ng/ml group detected by flow cytometry were(45.45<2.36)% and(35.04<5.64)%,respectively,which were significantly higher than that of M231-smooth muscle growth supplements control group [(2.60<0.95)%,all P<0.01]. The apoptotic indexes of groups incubated with RPM and RPM-PLGA-NPs for 24 hours were significantly higher than those of groups which incubated for 12 hours(P<0.05,P<0.01). The positive expression indexes(PEI)of p27(kip1) and bcl-2 protein were higher in RPM and RPM-PLGA-NPs groups than that of control groups. The Spearman's rank correlation coefficient test showed that there was no significant correlation between the PEI of p27(kip1) and the apoptotic indexes in the RPM group and RPM-PLGA-NPs group(P>0.05).</p><p><b>CONCLUSIONS</b>Rapamycin-loaded PLGA nanoparticles and rapamycin have similar effects in inhibiting proliferation and inducing apoptosis;meanwhile,they upregulate the expression of p27(kip1) protein without downregulating the expression of bcl-2 protein in HUASMCs in vitro. RPM-PLGA-NPs has more potent pro-apoptotic effect than equivalent dose of RPM but is not linearly correlated with the p27(kip1) expression level.</p>

Effect of p27 gene combined with Pientzehuang (characters: see text) on tumor growth in osteosarcoma-bearing nude mice / 中国结合医学杂志

<p><b>OBJECTIVE</b>To observe the effect of p27 gene recombinant adenovirus combined with Chinese medicine Pientzehuang ([characters: see text]) on the growth of xenografted human osteosarcoma in nude mice.</p><p><b>METHODS</b>Tissue transplantation was used to construct the orthotopic model of human osteosarcoma Saos-2 cell in nude mice. Thirty tumor-bearing nude mice were randomly divided into 5 groups with 6 mice in each group: blank control group (model of osteosarcoma), empty vector group (recombinant adeno-associated virus-multiple cloning site), Pientzehuang group, p27 gene group and combined treatment group (p27 gene combined with Pientzehuang). The effect of combined treatment on human osteosarcoma was analyzed through the tumor formation, tumor volume and inhibition rate of tumor growth. The expression of p27 was measured by immunohistochemical staining and Western blot.</p><p><b>RESULTS</b>The orthotopic model of osteosarcoma in nude mice was successfully constructed. The general appearance of tumor-bearing nude mice in Pientzehuang and p27 gene groups was markedly improved compared with the blank control group; and in the combined treatment group it was significantly improved compared with the Pientzehuang and p27 gene groups. The tumor growth in the Pientzehuang and p27 gene groups was significantly inhibited compared with the blank control group P<0.05); while in the combined treatment group it was markedly inhibited compared with the Pientzehuang and p27 gene groups (P<0.05). The rates of tumor growth inhibition were 34.1%, 56.5% and 63.8% in the Pientzehuang, p27 gene and combined treatment groups, respectively. Meanwhile, the protein expression of p27 gene in the p27 gene group was significantly increased compared with the blank control group (P<0.05); and it was significantly increased in the combined treatment group compared with the p27 gene and Pientzehuang groups (P<0.05).</p><p><b>CONCLUSION</b>p27 gene introduced by adenovirus combined with Pientzehuang can inhibit the growth of human osteosarcoma cell Saos-2 in nude mice.</p>

Uchl1 and its associated proteins were involved in spermatocyte apoptosis in mouse experimental cryptorchidism / 生理学报

Uchl1 was found to be involved in spermatocyte apoptosis. The aim of the present study was to test whether Uchl1 and its associated proteins Jab1 and p27(kip1) were involved in spermatogenic damages in response to heat-stress in cryptorchidism. Hematoxylin and eosin (HE) staining and DNA end labeling (TUNEL) were used to observe morphological and apoptotic characteristics of spermatogenic cells; Immunohistochemical analysis was used to detect changes of Uchl1 and its associated proteins Jab1 and p27(kip1) in response to heat-stress from cryptorchidism leading to spermatocyte losses; And protein affinity analysis (pull-down) and immunofluorescence co-localization were used to verify the relevance among the three proteins in spermatocytes. The results showed that, Jab1 and p27(kip1), in parallel to Uchl1, increased in spermatocytes of apoptotic appearances in response to heat-stress, but not in multinucleated giant cells; Jab1 bound to Uchl1 in testis protein extracts, and co-localized with Uchl1 and p27(kip1) specifically in spermatocytes with apoptotic appearances. These results suggest that the accumulation of Uchl1 protein is involved in the heat-stress-induced spermatocyte apoptosis through a new pathway related with Jab1 and p27(kip1), but not the formation of multinucleated giant cells.

Effect of downregulation of Tiam1 by siRNA on esophageal squamous cell carcinoma EC9706 cells / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To explore the effect of downregulation of Tiam1 by siRNA on the esophageal squamous cell carcinoma (ESCC) EC9706 cells, and provide theoretical basis for gene therapy of ESCC using Tiam1 as a molecular target.</p><p><b>METHODS</b>Tiam1 siRNA was transfected into EC9706 cells, and expression changes of Tiam1 mRNA and protein after transfection were detected by quantitative real-time PCR and Western blotting. Cell proliferation was analyzed using CCK-8 kit. Cell cycle and apoptosis of the EC9706 cells were assessed by flow cytometry. Cell cycle-related proteins and cell apoptosis-associated proteins were analyzed by Western blotting.</p><p><b>RESULTS</b>Compared with the untreated group and control siRNA group, the relative expression levels of Tiam1 mRNA (1.00 and 0.11 ± 0.02) were not significantly different (P > 0.05). The relative expression levels of Tiam1 mRNA in the Tiam1 siRNA group at 24, 48 and 72 h after transfection were 0.30 ± 0.04, 0.09 ± 0.01 and 0.09 ± 0.006, respectively, significantly lower than that of the untreated group (P < 0.05 for all). The expression level of Tiam1 protein at 24 h after Tiam1 siRNA transfection in the EC9706 cells was 0.11 ± 0.02, significantly lower than that in the un-treated group (0.44 ± 0.05) and control siRNA group (0.44 ± 0.04, P < 0.05 for all). The percentages of G0/G1 cells in the Tiam1 siRNA group, untreated group and control siRNA group were (54.48 ± 2.14)%, (40.69 ± 1.85)% and (41.78 ± 1.31)%, respectively (P < 0.01). The percentages of S phase cells in the Tiam1 siRNA group, untreated group and control siRNA group were (27.18 ± 1.65)%, (32.32 ± 1.15)% and (30.35 ± 1.09)%, respectively (P < 0.01). The expression levels of cyclin D1 protein in the untreated group, control siRNA group and Tiam1 siRNA group were 0.43 ± 0.02, 0.41 ± 0.01 and 0.11 ± 0.02, respectively (P < 0.05). The expression levels of p27 protein in the untreated group, control siRNA group and Tiam1 siRNA group were 0.10 ± 0.01, 0.09 ± 0.02 and 0.20 ± 0.02, respectively (P < 0.05). The ratios of early apoptotic cells in the untreated group, control siRNA group and Tiam1 siRNA group were (10 ± 0.9)%, (10 ± 0.5)% and (27 ± 0.7)%, respectively (P < 0.01). The expression levels of Mcl-1 protein in EC9706 cells of untreated group, control siRNA group and Tiam1 siRNA group were 0.47 ± 0.12, 0.48 ± 0.13 and 0.16 ± 0.02, respectively (P < 0.05). The expression levels of Bcl-2 protein in EC9706 cells of the untreated group, control siRNA group and Tiam1 siRNA group were 0.49 ± 0.08, 0.50 ± 0.05 and 0.04 ± 0.03, respectively (P < 0.05). The caspase-3 activities in the untreated group, control siRNA group and Tiam1 siRNA group were 2.3 ± 0.09, 2.3 ± 0.10 and 16.0 ± 1.50, respectively; and that of caspase-9 were 2.3 ± 0.08, 2.3 ± 0.11 and 14.5 ± 0.9, respectively (P < 0.05 for all).</p><p><b>CONCLUSIONS</b>Tiam1 siRNA can significantly inhibit the proliferation of esophageal cancer EC9706 cells, induce cell cycle arrest and cell apoptosis. These effects are related to the regulation of the expressions of cell cycle-related genes (cyclin D1 and p27) and cell apoptosis-related genes (Mcl-1, Bcl-1, caspase-3 and caspase-9) by Tiam1 siRNA.</p>

Aberrant expression of CyclinE and p27 in laryngeal squamous cell carcinoma and the clinical significance / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To explore new hallmarks affecting the prognosis of patients with laryngeal squamous cell carcinoma (LSCC) via investigating the expression of CyclinE and p27 in LSCC tissues.@*METHOD@#The expression of CyclinE and p27 was detected via Elivision immunohistochemical staining in 160 LSCC tissues and 20 normal laryngeal tissues (NLT). The relationship between CyclinE/ p27 and LSCC/ NLT was analyzed via Log-rank analysis. The relationship of CyclinE and p27 protein was statistically analyzed by spearman correlation analysis. The relationship between CyclinE/p27 and clinical-pathology-factors of patients with LSCC, such as age, gender, tumor site, diameter, differentiation, lymph node metastasis and PTNM stage were analyzed by Chi-square test. The relationship between clinical-pathology-factors, CyclinE, p27 and overall survival time of patients with LSCC was analyzed via Cox multiplicity and Kaplan-Meier survival analysis. A significant difference was recognized by P0.05 for all). A negative correlation was found between the expression of CyclinE and p27 protein, r= -0.767(P<0.05). Kaplan-Meier survival analysis showed that the overall survival rate of patients with LSCC was 36.9% (P<0.05). The 5-year survival rate in positive group of CyclinE was 8%, in negative group was 80% (P<0.05). On the contrary, the 5-year survival rate of patients with LSCC in positive group of p27 protein was 77.27%, the rate was 5.32% in negative group (P<0.05). Cox multivariate regression analysis revealed that lymph node metastasis, PTNM stage, CyclinE and p27 were independent risk factors of prognosis for patients with LSCC.@*CONCLUSION@#It is the molecular basis underlying the development and invasion/ metastasis of LSCC that activation of CyclinE gene accompanying inactivation of p27 gene. It is very important of co-detecting CyclinE and p27 protein to predict the prognosis of patients with LSCC.

Different responses of cell cycle between rat vascular smooth muscle cells and vascular endothelial cells to paclitaxel / 华中科技大学学报（医学）（英德文版）

Although previous reports showed drug-eluting stent (DES) could effectively inhibit neointima formation, in-stent restenosis (ISR) remains an important obstacle. The purpose of this study was to investigate different effects of paclitaxel on proliferation and cell cycle regulators between vascular smooth muscle cells (VSMCs) and vascular endothelial cells (VECs) of rats in vitro. The cultured VSMCs and VECs of rats from the same tissues were examined by using immunohistochemistry, flow cytometry and Western blotting in control and paclitaxel-treated groups. The results showed paclitaxel could effectively inhibit proliferation of VSMCs and VECs. However, as compared with VECs, proliferation of VSMCs in paclitaxel-treated group decreased less rapidly. The percentage of cells in G0-G1 and G2-M phases was reduced, and that in S phase increased after treatment for 72 h. The expression of cyclin D1 and B1, p27 and PCNA in VSMCs of paclitaxel-treated group was up-regulated, but that of p21 down-regulated as compared with VECs. It is concluded that there are significant differences in the expression of cell cycle regulators and proliferation rate between paclitaxel-treated VSMCs and paclitaxel-treated VECs, suggesting that the G1-S checkpoint regulated by paclitaxel may play a critical role in the development of complications of DES, which provides new strategies for treatments of ISR.

p27 Loss Is Associated with Poor Prognosis in Gastroenteropancreatic Neuroendocrine Tumors / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) represent a heterogeneous disease group originating from the neuroendocrine cells. Identification of prognostic markers, related to neuroendocrine tissue-selective tumorigenesis, is necessary to find therapeutic targets. MATERIALS AND METHODS: A total of 327 patients with GEP-NETs were included in this study; there were 49 gastric, 29 duodenal, 49 pancreatic, 12 hepatobiliary, 33 appendiceal, 5 proximal colon, and 150 distal colon cases. We performed immunostaining with the tissue microarray method for menin, p27, and p18. RESULTS: We observed negative staining for menin, p27, and p18 in 34%, 21%, and 56% of GEP-NETs, respectively. The loss of p27, but not menin, was positively correlated with the grade of Ki-67. Menin-/p27-, menin-/p27+, menin+/p27-, and menin+/p27+ phenotype groups included 13%, 22%, 8%, and 57% of patients, respectively. A dichotomized comparison showed that menin- or p27- tumors were significantly associated with foregut and midgut localizations, high World Health Organization (WHO) grade, lymph node metastasis, and more advanced stage as compared to menin+/p27+ patients. Kaplan-Meier analysis for the overall survival showed that p27 loss was significantly associated with decreased survival. Multivariate analysis showed that p27 loss is an independent factor for poor overall survival. CONCLUSION: Our results revealed that the loss of p27 is associated with poor prognosis and the menin-p27 pathway is important in the tumorigenesis of GEP-NETs.

Silencing of KIF14 interferes with cell cycle progression and cytokinesis by blocking the p27(Kip1) ubiquitination pathway in hepatocellular carcinoma

Although it has been suggested that kinesin family member 14 (KIF14) has oncogenic potential in various cancers, including hepatocellular carcinoma (HCC), the molecular mechanism of this potential remains unknown. We aimed to elucidate the role of KIF14 in hepatocarcinogenesis by knocking down KIF14 in HCC cells that overexpressed KIF14. After KIF14 knockdown, changes in tumor cell growth, cell cycle and cytokinesis were examined. We also examined cell cycle regulatory molecules and upstream Skp1/Cul1/F-box (SCF) complex molecules. Knockdown of KIF14 resulted in suppression of cell proliferation and failure of cytokinesis, whereas KIF14 overexpression increased cell proliferation. In KIF14-silenced cells, the levels of cyclins E1, D1 and B1 were profoundly decreased compared with control cells. Of the cyclin-dependent kinase inhibitors, the p27Kip1 protein level specifically increased after KIF14 knockdown. The increase in p27Kip1 was not due to elevation of its mRNA level, but was due to inhibition of the proteasome-dependent degradation pathway. To explore the pathway upstream of this event, we measured the levels of SCF complex molecules, including Skp1, Skp2, Cul1, Roc1 and Cks1. The levels of Skp2 and its cofactor Cks1 decreased in the KIF14 knockdown cells where p27Kip1 accumulated. Overexpression of Skp2 in the KIF14 knockdown cells attenuated the failure of cytokinesis. On the basis of these results, we postulate that KIF14 knockdown downregulates the expression of Skp2 and Cks1, which target p27Kip1 for degradation by the 26S proteasome, leading to accumulation of p27Kip1. The downregulation of Skp2 and Cks1 also resulted in cytokinesis failure, which may inhibit tumor growth. To the best of our knowledge, this is the first report that has identified the molecular target and oncogenic effect of KIF14 in HCC.

Role of co-expression of c-Myc, EZH2 and p27 in prognosis of prostate cancer patients after surgery / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>c-Myc, EZH2 and p27 were defined to modulate the behavior of prostate cancer with pro-tumoral or anti-tumoral effects and had ability in predicting prostate cancer progression, but the research of their co-expression value of prognosis is rarely. This study aimed to investigate the prognostic value of combining tri-marker together in patients with intermediate-risk prostate cancer after surgery.</p><p><b>METHODS</b>Expression levels of c-Myc, EZH2 and p27 in 129 patients with intermediate-risk prostate cancer were assessed using immunohistochemistry in a semi-quantitative manner. The expression profiles of these three markers were analyzed and investigated for association with biochemical recurrence.</p><p><b>RESULTS</b>In all, fifty of 129 cases experienced biochemical recurrence during a median follow-up time of 31 months (range, 6 - 60 months). Of these relapse patients, one case without and 10 cases with any single positive marker were observed; 39 cases were detected with any two or all three positive markers (22 cases with any two and 17 cases with all three positive markers). Survival analysis showed that patients with over-expression of c-Myc or EZH2, and lower expression of p27 manifested significantly higher biochemical recurrence rates. Subsequent multivariate analysis revealed that c-Myc, EZH2 and p27 expression statuses showed potential in predicting relapse, respectively. Notably, combining three markers together as a "composite index" (0 or 1, vs. 2 or 3 positive markers) provided powerful prognostic value (HR 6.57, 95% CI 3.02 - 14.31, P < 0.001). There was a significant difference between the patient subgroups with 0 or 1 and those with 2 or 3 positive markers expression statuses, and tri-marker composite index was an independent risk factor for predicting relapse in patients with intermediate-risk prostate cancer after surgery.</p><p><b>CONCLUSION</b>Composite index of c-Myc, EZH2, and p27 can be valued as powerful prognosis parameter for intermediate-risk prostate cancer patients after the surgery, and postoperative adjuvant therapy can be adopted accordingly.</p>

Cytoplasmic expression of P27 protein and its correlation with clinicopathologic features of nasopharyngeal carcinoma / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the correlation of p27 protein expression in the cytoplasm with the clinicopathologic features of nasopharyngeal carcinoma (NPC).</p><p><b>METHODS</b>Immunohistochemistry was employed to examine P27 protein expression in the cytoplasm of NPC samples and nasopharyngeal (NP) tissue samples. The differential expression of P27 protein between NPCs and NPs and the correlation of cytoplasmic P27 protein expression with the clinicopathologic parameters of NPC patients was analyzed. RESULTS Immunohistochemistry indicated significantly down-regulated t p27 protein expression in NPC tissues compared to that in NP tissues (P=0.047). The reduction of P27 expression was inversely correlated with T classification of NPC (P=0.033). Although cytoplasmic p27 protein expression was not significantly correlated with lymph node metastasis (P=0.157) or clinical stages of NPC (P=0.090), an obvious trend of inverse correlations between them was noted.</p><p><b>CONCLUSION</b>Down-regulated cytoplasmic p27 protein expression may promote the carcinogenesis of NPC and can be an unfavorable prognostic factor for survival of NPC patients.</p>