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1.
Cyclin D1/p16/pRb pathway controlling G1→S cell cycle checkpoint is frequently altered in human tumors. Currently, scarce data are available for parathyroid tumors. We have studied 46 parathyroid adenomas (PTAs) and 12 normal parathyroid glands (PTGs) by immunohistochemistry with cyclin D1 (CD1), p16, pRb, and Ki-67 antibodies. We observed CD1 expression in 89%, p16 in 70%, and pRb in 100% of PTAs. Statistically significant differences with normal PTGs were found only concerning p16 expression (p<0.05). Proliferating rate (Ki-67) was always low, although significantly higher than in normal PTGs. Our findings demonstrate the presence of alterations in the CD1/p16/pRb pathway in PTAs, consisting in p16 overexpression apparently unrelated to pRb downregulation. On the other hand, we did not find significant differences in CD1 expression between PTAs and normal PTGs, suggesting CD1 overexpression could be a physiological event in parathyroid tissue.  相似文献   

2.
The aim of this study was to assess immunohistochemical expression of p53, pRb, p16, and cyclin D1, alone or in combination, as prognostic indicators and to investigate their correlation with clinocopathologic features of urothelial carcinoma. Immunohistochemical staining for p53, pRb, p16, and cyclin D1 was performed on a tissue microarray from 103 patients with urothelial carcinoma who underwent radical cystectomy. Of the patient samples analyzed, 36 (35%), 61 (59%), 47 (46%) and 30 (29%) had altered expression of p53, pRb, p16, and cyclin D1, respectively. Abnormal expression of p53 and pRb correlated with depth of invasion (P=0.040 and P=0.044, respectively). Cyclin D1 expression was associated with tumor stage and recurrence (P=0.017 and P=0.036, respectively). Altered pRb was significantly correlated with overall survival (P=0.040). According to the expression pattern of pRb and p53, p53/pRb (altered/normal) had worse survival than p53/pRb (normal/altered) (P=0.022). Alteration of all markers had worse survival than all normal (P=0.029). As determined by multivariate analysis, tumor stage, lymph node metastasis and the combined expression of p53 and pRb are independent prognostic factors. In conclusion, immunohistochemical evaluation of cell cycle regulators, especially the p53/pRb combination, might be useful in planning appropriate treatment strategies.  相似文献   

3.
Cyclin D3 expression in primary Ta/T1 bladder cancer   总被引:4,自引:0,他引:4  
Cyclin D3 deregulation has recently been reported in bladder cancer but its prognostic significance remains uncertain. A cohort of 159 patients with stage Ta or T1 primary bladder tumours was investigated to determine the significance of cyclin D3 expression in association with other G1-S phase regulators of the cell cycle (p53, p21Waf1, p27kip1, cyclin D1), including tumour proliferation (ki67-MIB1); its association with conventional clinicopathological parameters; and the relationship between cyclin D3 and loss of heterozygosity (LOH) at the 9p21 (p16INK4a locus) chromosome region. The end point of the study was progression-free survival. Cyclin D3, other G1-S phase regulators, and tumour proliferation were investigated by immunohistochemistry and measured by the grid-counting method. To validate the immunohistochemical expression, cyclin D3 was additionally assessed by western blotting in selected cases. LOH at the 9p21 chromosome region (marker D9S171) was assessed in 125 cases using an AB Prism 310 genetic analyser and a set of microsatellite fluorescence-labelled primers. Cyclin D3 overexpression was related to larger tumour size (>5 cm; p < 0.0001) and high tumour proliferation (>10%; p = 0.025). Mean cyclin D3 expression increased with 2004 WHO grading categories in stage Ta (p = 0.035, ANOVA) and stage T1 (p = 0.047, t test) tumours. Cyclin D3 was not related to other clinicopathological parameters, G1-S phase modulators, or 9p21 LOH. Cox's multivariate analysis selected cyclin D3 as an independent predictor of progression-free survival (p = 0.0012, relative risk (RR) = 5.2366) together with tumour size (p = 0.0115, RR = 4.4442) and cyclin D1 (p = 0.0065, RR = 3.3023). Cyclin D3 expression had the highest risk ratio. Our results suggest that expression of cyclin D3 is relevant to the progression-free survival of patients with Ta/T1 bladder carcinomas.  相似文献   

4.
The retinoblastoma (Rb) pathway controls the G1-S checkpoint of the cell cycle. Inactivating mutations and deletions of p16 and Rb and up-regulation of cyclin D1 disrupt this pathway and occur in many cancers. However, the concurrent expression of these genes in primary and metastatic gastric cancer is unknown, and the prognostic value of their expression is unclear. In this study, the expression of cyclin D1, retinoblastoma protein (pRb), and p16 in 67 resected gastric adenocarcinomas, and of pRb and p16 in 40 associated lymph node metastases, was determined using a streptavidin-biotin-peroxidase immunohistochemical method. Relationships with clinical and pathological features were analyzed. Cyclin D1 overexpression (>/=5% expression) was seen in 55% of cancers; pRb loss (<20% expression), in 33%; p16 loss (<10% expression), in 49%; and at least 1 of these abnormalities, in 92.5%. Cyclin D1 overexpression was associated with poor differentiation (P = 0.027) and signet ring cell type (P = 0.029). pRb expression was lower in lymph node metastases than in the corresponding primary tumors (P <0.001). Univariate and multivariate survival analysis (minimum follow-up 72 months or until death) revealed that <20% pRb expression, <30% pRb expression, and International Union Against Cancer stage >2 were associated with worse overall survival. The results suggest that Rb pathway disturbances play an important role in gastric carcinogenesis. The poor prognosis of cancers with low pRb expression and the reduced pRb expression in lymph node metastases raise the possibility that Rb and related genes also influence progression.  相似文献   

5.
Two molecular pathways leading to cancer are known. Common-type cancers arise from the ‘tumour suppressor’ pathway, characterized by gross chromosomal changes and allelic losses (LOH) in an average of 25 per cent or more of randomly chosen chromosomal loci. The ‘mutator pathway’ has been recognized in a subset of cancers, characterized by widespread microsatellite DNA instability and rarity of chromosomal losses. The present study has investigated 20 pancreatic endocrine tumours (PETs) for loss of heterozygosity (LOH) at seven chromosomal loci (3p14, 7q31–32, 11q13, 13q14, 18q21, 17p13, and 17q21); microsatellite instability; and Ki-ras, N-ras, and p53 gene mutations. LOH was found in an average of 24 per cent of the chromosomal loci analysed. No tumour showed microsatellite instability. Ki-ras and p53 mutations were each found in one case. The frequency of losses was higher in malignant (40 per cent) than in benign (17 per cent) tumours (p=0·009), and the specific chromosome 17p13 LOH was associated with extrapancreatic extension of disease (p=0·007), high proliferative activity (p=0·001), and absence of progesterone receptors (p=0·01). A common deleted region on chromosome 17p13 and the rarity of p53 gene mutations suggest the existence of a novel tumour suppressor gene involved in the pathogenesis of PETs in this chromosomal area. © 1998 John Wiley & Sons, Ltd.  相似文献   

6.
We aimed to assess protein expressions of p16 and pRB in breast cancer and explore the clinicopathologic implications. Tissue microarray (TMA) was constructed with 406 cases of breast cancer. The cases were subgrouped into luminal A, luminal B, HER-2, and triple negative breast cancer (TNBC) based on the results of immunohistochemical stains for ER, PR, HER-2, and Ki-67 and fluorescent in situ hybridization (FISH) for HER-2. One hundred and sixty-eight cases were allocated to the subgroup luminal A; 87 cases to the luminal B; 32 cases to the HER-2; and 119 cases to the TNBC. The TNBC group showed the highest negative rate for p16, and the luminal B and HER-2 groups showed the highest positive rate for p16 (P < 0.001). Alteration of p16 was the highest in the luminal B and HER-2 groups, and pRB expression rate was the highest in the HER-2 group and lowest in the luminal A group. In addition, p16(+)/pRB(+) type was the most common in the luminal B group, p16(+)/pRB(-) in the luminal A group, and p16(-)/pRB(+) in the TNBC group (P < 0.001). Altered p16/pRB(+) and non-altered p16/pRB(+) type was the most common in the luminal B, and altered p16/pRB(-) and non-altered p16/pRB(+) type was the most common in the luminal A (P < 0.001). Alteration of p16 was correlated with higher Ki67 labeling index (LI) (P = 0.013), and p16 negativity was correlated with ER negativity (P = 0.002), PR negativity (P = 0.004), and higher Ki67 LI (P < 0.001). pRB positivity was correlated with PR negativity (P = 0.009), HER-2 positivity (P = 0.001), and higher Ki-67 LI (P < 0.001). In luminal group A, p16 alteration was correlated with shorter DFS in univariate analysis (P = 0.024). In conclusion, Expression rates of p16 and pRB differ according to the molecular subgroups of breast cancer and they subsequently correlate with clnicopathologic factors.  相似文献   

7.
We recently reported that the vast majority (>90%) of low‐grade diffuse gliomas (diffuse astrocytoma, oligoastrocytoma and oligodendroglioma) carry at least one of the following genetic alterations: IDH1/2 mutation, TP53 mutation or 1p/19q loss. Only 7% of cases were triple‐negative (ie, lacking any of these alterations). In the present study, array comparative genomic hybridization (CGH) in 15 triple‐negative WHO grade II gliomas (eight diffuse astrocytomas and seven oligodendrogliomas) showed loss at 9p21 (p14ARF, p15INK4b, p16INK4a loci) and 13q14–13q32 (containing the RB1 locus) in three and two cases, respectively. Further analyses in 31 triple‐negative cases as well as a total of 160 non‐triple‐negative cases revealed that alterations in the RB1 pathway (homozygous deletion and promoter methylation of the p15INK4b, p16INK4a and RB1 genes) were significantly more frequent in triple‐negative (26%) than in non‐triple‐negative cases (11%; P = 0.0371). Multivariate analysis after adjustment for age, histology and treatment showed that RB1 pathway alterations were significantly associated with unfavorable outcome for patients with low‐grade diffuse glioma [hazard ratio, 3.024 (1.279–6.631); P = 0.0057]. These results suggest that a fraction of low‐grade diffuse gliomas lacking common genetic alterations may develop through a distinct genetic pathway, which may include loss of cell‐cycle control regulated by the RB1 pathway.  相似文献   

8.
9.

Introduction

Recent studies have demonstrated the critical roles of micro-RNAs in tumorigenesis and tumor progression. Here, we describe the regulation and function of miR-490-5p in bladder cancer.

Material and methods

Paired tissue samples were collected from bladder cancer patients (n = 20). Real-time PCR revealed that miR-490-5p expression was significantly down-regulated in human bladder cancer tissues and cells. Also there was an inverse relationship between the expression level of miR-490-5p and the pathological grade of bladder cancer. Western blotting was performed to detect the expression levels of c-FOS and TET1 in 6 matched tumor tissue samples and 4 bladder cell lines. Furthermore, to better understand the underlying mechanisms of miR-490-5p, we conducted gain and loss of function analysis by transfecting bladder cancer T24 cells with chemically synthesized miR-490-5p mimics and inhibitor, respectively.

Results

We found that overexpression of miR-490-5p in T24 cells could inhibit cell proliferation and invasion and induce cell apoptosis. Conversely, suppression of miR-490-5p expression induced cell proliferation and invasion, while it inhibited cell apoptosis. In addition, our bioinformatics prediction and experimental data showed that c-FOS was a potential target of miR-490-5p. The expression level of c-FOS was significantly decreased after miR-490-5p overexpression and significantly increased after miR-490-5p suppression, indicating that c-FOS was a target of miR-490-5p.

Conclusions

These findings suggest that miR-490-5p is a novel tumor suppressor, contributing to the carcinogenesis of bladder cancer by targeting c-FOS.  相似文献   

10.
The biological behaviour of urinary bladder neoplasms cannot be adequately predicted by histological criteria alone. Cyclin D1 is a cell-cycle regulating protein known to be overexpressed in a proportion of bladder carcinomas. To evaluate the prognostic significance of cyclin D1 expression and its relationship with tumour phenotype, 392 bladder carcinomas were analysed by immunohistochemistry. Clinical follow-up information was available in 337 patients with superficial bladder tumours (stages pTa/pT1). Cyclin D1 positivity was seen in 176 of 392 carcinomas. Cyclin D1 overexpression was strongly linked to papillary tumour growth, low stage, and low histological grade (p<0·005 each). Multivariate analysis showed that papillary tumour growth was the only parameter which was independently linked to cyclin D1 positivity. There was no significant difference in proliferative activity (Ki67 labelling index) between cyclin D1-negative and -positive tumours. Cyclin D1 positivity was not linked to the risk of recurrence or tumour progression, either in pTa or in pT1 carcinomas. It is concluded that cyclin D1 positivity distinguishes a large subgroup of papillary bladder tumours, but there is no evidence of prognostic significance for increased cyclin D1 expression. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   

11.
The role of cell cycle regulatory proteins in the pathogenesis of melanoma   总被引:4,自引:0,他引:4  
The transformation of melanocytes to melanoma cells is characterised by abnormal proliferation resulting from alterations in cell cycle regulatory mechanisms. This occurs through alterations in the two major cell cycle regulatory pathways, the retinoblastoma (Rb) and p53 tumour suppressor pathways. This review summarises the current knowledge of alterations in these two pathways at G1/S transition and specifically the role of the key cell cycle regulatory proteins pRb, p16INK4a (p16), cyclin D1, p27Kip1 (p27), p53 and p21Waf1/Cip1 (p21) in the pathogenesis of melanoma. It also considers their prognostic significance. Current data indicate that alterations of cyclin kinase inhibitor (cdki) levels are implicated in the pathogenesis of melanoma and may be useful prognostic markers. However, large validation studies linked to comprehensive clinical follow up data are necessary to clarify the prognostic significance of cell cycle regulatory proteins in individual patients.  相似文献   

12.
13.
There is limited data regarding the association between the expression of cell cycle-regulating molecules and the response of patients with urothelial carcinoma in situ (CIS) to bacillus Calmette-Guerin (BCG) therapy. To examine the relationship between p16, pRb and p53 expression in bladder CIS and patient response to initial BCG therapy, we performed immunohistochemical studies for 27 patients with bladder CIS. Overexpression of p16, pRb, and p53 was observed in 37%, 41%, and 48% of patients, respectively. Initial BCG therapy was effective in 21 patients (78%). Coexistence of papillary urothelial carcinoma, depth (pTa or pT1) and grade of coexisting papillary carcinoma did not affect the response to BCG therapy. pRb overexpression had a significant relationship to poor response to BCG therapy (P= 0.027). The results of this study indicate that overexpression of pRb in bladder CIS predicts poor response of intravesical BCG instillation and status of p16 and p53 may not be predictive of initial BCG failure.  相似文献   

14.
This review aims to present data on the association between human papillomavirus (HPV) and urinary bladder cancer (BC), especially of the subtype squamous cell carcinoma (SCC). Furthermore, the current data on the relation between p16, HPV, and BC are reviewed. PubMed was searched for ‘Humans’ [MESH] AND ‘Papillomaviridae’ [MESH] AND ‘Urinary Bladder Neoplasms’ [MESH], resulting in 157 potential articles. After profound reviewing, 18 articles were included in this review. Only original articles in English were included. A variable number of HPV genotypes in a small number of cases have been investigated in several studies with various methodology. HPV was present in 0–100% of cases depending on inclusion and exclusion criteria. SCC studies are mostly hampered by low number of cases whereas the few studies with a high number show a slightly higher prevalence of different HPV genotypes compared to pure urothelial carcinoma. Studies on p16 status in HPV positive cases are even more scarcely reported and show conflicting results. Most studies fail to prove clear-cut relevance of HPV in BC irrespectively of histological subtype. Negative p16 staining cannot rule out positive HPV status.  相似文献   

15.
p16、Rb和cyclin D1蛋白在横纹肌肉瘤中的表达及其意义   总被引:6,自引:0,他引:6  
目的:探讨细胞周期相关蛋白表达异常与横纹肌肉瘤(RMS)的关系。方法:应用S-P免疫组化方法观察p16,Rb和cyclinD1蛋白在RMS中的表达状态。结果:p16,Rb和cyclinD1蛋白表达阳性率分别为55.3%,61.7%和51.1%,在胚胎性横纹肌肉瘤(ERMS),p16和Rb蛋白表达阳性率为75.0%(21/28)和67.9%(19/28),明显高于在腺泡状横纹肌肉瘤(ARMS)中的表达(P<0.05),p16蛋白阳性率在I,Ⅱ级横纹肌肉瘤分别为75.0%和73.3%,高于Ⅲ级横纹肌肉瘤(45.0%);p16蛋白阴性及cyclinD1蛋白过表达组,局部浸润,复发或转移发生率高于p16蛋白阳性及cyclinD1蛋白阴性组;11/47例(23.4%)出现两种以上蛋白表达异常。结论:P16,Rb和cyclinD1蛋白异常可能与部分横纹肌肉瘤发生发展有关,且横纹肌肉瘤的发生可能涉及两种以上基因异常。  相似文献   

16.
Tumour progression can be investigated in liposarcomas showing a transition from a low-grade well-differentiated (WD) to a high-grade dedifferentiated (DD) variant. As RB1 gene alterations are common defects in sarcomas, this study examined the frequency of RB1 loss of heterozygosity (LOH) in a group of 14 well-differentiated liposarcomas (WDLs) and 17 well-differentiated/dedifferentiated liposarcomas (WD/DDLs), using a microdissection approach (PALM laser pressure catapulting) that allows the two histological components to be separated for polymerase chain reaction (PCR) analysis. In addition, RB1 protein expression and the Mib1 proliferation index were determined by immunohistochemistry and interphase FISH was performed with an RB1 probe at 13q14. By the use of four intragenic polymorphic RB1 markers (introns 1, 17, 20, and 25) for PCR, allelic losses were found only in the DD parts, but never in the pure WDLs or in the WD components of the WD/DDLs investigated. Furthermore, DD areas characterized by a heterogeneous RB1 protein expression pattern (35-65% immunopositivity), as compared with 90-100% RB1 positivity in WD areas, showed a marked increase in Mib1 proliferation index (19.6% versus 1.8% in WD areas; p<0.001). Interphase fluorescence in situ hybridization (FISH) detected a higher RB1-LOH rate in the DD components of WD/DDLs. Considering the different detection sensitivities of the three methodologies, it is concluded that loss of RB1 function already begins in the WDL, and that the tumour cell population with RB1-LOH starts prevailing in the tumour mass during progression of a WDL.  相似文献   

17.
p16(INK4a) is known to play a critical role as a negative regulator of cell cycle progression and differentiation by controlling the activity of the tumor-suppressor protein pRb. The present study evaluated the expression of p16(INK4a) and pRb in cervical squamous and glandular neoplasia. Immunohistochemical staining was performed for p16(INK4a) and pRb in formalin-fixed, paraffin-embedded tissue sections of the uterine cervix using an indirect immunoperoxidase method. p16(INK4a) staining was detected in 7 of 108 sections (6.5%) of normal squamous mucosa, in scattered ciliated columnar cells in 33 of 88 sections (37.5%) of normal endocervical glands, in 9 of 30 sections (30%) with Nabothian cysts, and in 4 of 4 areas (100%) of tubal metaplasia. In contrast, strong p16(INK4a) staining was found in 13 of 18 cases (72.2%) of cervical intraepithelial neoplasia (CIN) I and in all cases of CIN II/III (n = 46), squamous cell carcinoma (n = 18), endocervical glandular dysplasia (n = 10), adenocarcinoma in situ (n = 23), and invasive adenocarcinoma (n = 12). pRb expression was detected in each diagnostic category; however, the proportion of pRb-positive cells was relatively decreased in high-grade premalignant and malignant lesions of the squamous and endocervical mucosa and showed a generally inverse correlation with the expression of p16(INK4a) at the tissue level. These findings confirm a correlation between the expression of p16(INK4a) and pRb in cervical neoplasias and indicate that p16(INK4a) is a specific marker for premalignant and malignant lesions of the squamous and endocervical mucosa.  相似文献   

18.
High expression of thymidylate synthase (TS) is allegedly associated with the chemoresistance to 5-fluorouracil (5-FU) in colorectal cancers. However, low TS expression does not necessarily imply chemosensitivity. Inactivation of p16(INK4a) correlates with poor prognosis in various cancers. We immunohistochemically evaluated the relationship between the expression of TS, p16(INK4a), CDK4 and cyclin D1 and the effect of 5-FU-based chemotherapy in colorectal cancers. After antigen retrieval, immunoperoxidase staining was performed on the paraffin-embedded, biopsy and surgical specimens of 37 advanced colorectal cancers preoperatively treated with peroral administration of 5-FU derivatives. As a control group, 31 colorectal cancers without preoperative treatment were analyzed. High TS expression was found in 23 (74%) of 31 tumors resected from histological non-responders and in 19 (61%) of 31 controls but in none of six responders. High p16(INK4a) expression was seen in 83% of the responders, 52% of the non-responders and 32% of the controls. The TS-low/p16(INK4a)-high phenotype was noted in 83% of the responders, but only in 3% of the non-responders (P = 0.0001). Induction of p16(INK4a) expression after chemotherapy was predominantly seen in the responders. Neither CDK4 nor cyclin D1 expression was related to the chemotherapeutic effects. In conclusion, the combination of low expression of TS and induction of p16(INK4a) after chemotherapy can be important indicators of the sensitivity to 5-FU-based chemotherapy in colorectal cancers.  相似文献   

19.
Carcinoma of exocrine pancreas is the fourth leading cause of cancer deaths, worldwide. The prevalence of this disease is very high in patients with chronic pancreatitis. Orodigestive cancers are frequently seen in patients with periodontitis. These findings suggest that this type of cancer may have some bacterial origins. This study hypothesizes that the peptidyl arginine deaminase (PAD) enzymes found in oral bacteria may be responsible for the p53 point mutations that occur in patients with pancreatic cancer. Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, and Treponema denticola possess the PAD enzyme, and p53 arginine mutations have been detected in patients with pancreatic cancer. Moreover, the Pro allele p53Arg72-Pro is a risk factor for the development of this cancer. Anti-P. gingivalis antibody titers have been found to be higher in patients with pancreatic cancer as compared to healthy controls. The hypothesis in question can be tested if the DNA of P. gingivalis or the antibodies against P. gingivalis can be detected in patients with the p53 arginine mutation.If this hypothesis is true, it could reveal the real cause of pancreatic cancer, which is a fatal disease. Further studies are necessary in order to confirm this hypothesis.  相似文献   

20.
目的进一步了解miRNA在膀胱癌中的潜在机制。方法芯片分析4对人膀胱癌组织和相邻正常组织中的miRNA的表达。并用RT-q PCR来验证两个最上调的miRNA及其靶基因的表达是否符合miRNA/mRNA芯片结果。通过相关性分析和双荧光素酶报告实验推断并验证miR-130b-3p可以靶向PTEN。应用CCK8、EDU、流式细胞术、划痕、Transwell和细胞骨架等实验证明miR-130b可以影响膀胱癌细胞的增殖、凋亡、迁移和侵袭。用Western blot检测PI3K/AKT和整合素β1/FAK信号通路的关键靶蛋白。结果人膀胱癌中miR-130b-3p表达高于癌旁且与PTEN表达呈负相关。miR-130b-3p可下调PTEN表达,导致PI3K/AKT和整合素β1/FAK信号通路的激活,且与膀胱癌EJ细胞的增殖、迁移和侵袭相关。细胞转染miR-130b-3p抑制剂时,可以重排细胞骨架。结论本结果揭示miR-130b/PTEN有望用于人膀胱癌诊断和治疗的标志物。  相似文献   

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