Clinical and genetic characteristics of retinoblastoma patients in a single center with four novel RB1 variants

AIM:To assess the clinical and genetic characteristics of children diagnosed with retinoblastoma(RB)at Gazi University Faculty of Medicine’s Department of Pediatric Oncology.METHODS:All cases diagnosed with RB and received treatment and follow-up in the Ophthalmology and Pediatric Oncology Department,October 2016 to May 2021 were evaluated retrospectively.The RB1 gene was analyzed by next-generation sequencing(NGS)technique in DNAs obtained from peripheral blood samples of the patients.RESULTS:This study included 53 cases with 67 RBaffected eyes during the study period.The mean age was 24.6(median:18.5,range:3–151)mo.There were 15(22.3%)Group D eyes and 39(58.2%)Group E eyes.The RB1 gene was sequenced by the NGS method in 19 patients.Heterozygous RB1:NM_000321.3:c.54_76del(p.Glu19AlafsTer4)variant was detected in a 15-month-old female with bilateral RB.Heterozygous RB1:NM_000321.3:c.1814+3A>T variant was detected in a 5.5-month-old male with bilateral RB.The intronic RB1:NM_000321.3:c.1332+4A>G variant was detected in patient 14,a 13-month-old male with unilateral RB.The RB1:NM_000321.3:c.575_576del(p.Lys192SerfsTer10)variant was found in an 18-month-old female with an allele frequency of 37%.These variants have not been reported in the literature and mutation databases.CONCLUSION:Four novel variants are described and one of them is found in two different patients.This data is crucial for assessing prognosis.It serves as a guide for estimating the long-term risk of secondary malignancy as well as the short-term risk of developing additional malignancies in the same eye and the other eye.

Retinoblastoma binding protein 4 up-regulation is correlated with hepatic metastasis and poor prognosis in colon cancer patients

Background: Retinoblastoma binding protein 4 (RBBP4) plays an essential role in the development of multiple cancers. However, its relationship with prognosis in colon cancer and colon cancer hepatic metastasis has not been elucidated. The aim of this study was to explore the relationship between RBBP4 expression and prognosis of colon cancer patients and to evaluate RBBP4 as a new prognostic marker in these patients. Methods: Eighty colon cancer patients underwent surgical resection of the colon were enrolled. Among them, forty colon cancer patients suffered with hepatic metastasis. The colon cancer tissues, para-colon cancer tissues, and hepatic metastatic cancer tissues were collected from the pathological department for further analysis. The expression of RBBP4 proteins was examined by immunohistochemistry and correlated with clinicopathological parameters. The Cancer Genome Atlas (TCGA) database was used to validate the expression and explore its relationship with clinical characteristics. Results: RBBP4 was up-regulated in the colon cancer tissues compared with the para-colon cancer tissues. The analysis of TCGA database verified the upregulation of RBBP4 in the colon cancer tissues and RBBP4 overexpression was correlated with nerve invasion and poor outcomes of chemotherapy. Moreover, the positive rate of RBBP4 expression in 40 colon cancer patients with hepatic metastasis was higher in the hepatic metastatic cancer tissues (39/40, 97.5%) than in the colon cancer tissues (26/40, 65.0%). Our clinicopathological analysis showed that RBBP4 expression was significantly correlated with vascular invasion, hepatic metastasis, and lymph node involvement (all P < 0.05). Additionally, the survival analysis demonstrated that RBBP4 over-expression was correlated with poor prognosis. Conclusions: RBBP4 was upregulated in the colon cancer. RBBP4 may be a novel predictor for poor prognosis of colon cancer and colon cancer hepatic metastasis.

Effect on proliferation and apoptosis of retinoblastoma cell by RNA inhibiting high mobility group protein box-1 expression

AIM： To investigate the effect of high mobility group protein box-1 （HMGB1） siRNA on proliferation and apoptosis of retinoblastoma （Rb） cells.METHODS： The expression of HMGB1 in Rb cells were detected by real-time polymerase chain reaction （RT-PCR） and Western blot. Chemically synthesized HMGB1 siRNA was transfected into Y79 cells. The inhibitory rate was also examined by RT-PCR and Western blot. After HMGB1 siRNA transfection, the cell proliferation was analyzed by MTT, and cell apoptosis was detected by Caspase-3 active detection kit. Cell cycle distribution and apoptosis were detected by flow cytometry. RESULTS： The expression of HMGB1 significantly elevated in Rb cells （P〈0.01）. After transfected by siRNA, the HMGB1 protein level of Y79 cells was significantly reduced （P〈0.01）. After siRNA interference HMGB1, the proportion of proliferating cells reduced, and the proportion of quiescent cells increased （P〈0.05）. In addition, apoptosis rate of Y79 cells increased from 2.03% to 9.10% after interfering with HMGB1 siRNA （P〈0.05）.CONCLUSION： Specific HMGB1 siRNA can inhibit the expression of HMGB1. The effect may be attributed to inhibit the proliferation and promote cell apoptosis.

Expression of multidrug-resistance associated proteins in human retinoblastoma treated by primary enucleation

AIM： To reveal the expression of multidrug-resistance associated proteins： glutathione-S-transferase π（GSTπ）, P-glycoprotein（P-gp） and vault protein lung resistance protein（LRP） in retinoblastoma（RB） without any conservative treatment before primary enucleation and to correlate this expression with histopathological tumor features. METHODS： A total of 42 specimens of RB undergone primary enucleation were selected for the research. Sections from the formalin-fixed, paraffin-embedded specimens were stained with HE and immunohistochemistry to detect the expression of GSTπ, P-gp and LRP.RESULTS： GSTπ was expressed in 39/42（92.86%） RBs and in 9/9（100%） well-differentiated RBs. P-gp/GSTπ was found in 30（71.42%） of 42 RBs. Totally 9（21.43%） tumors were well differentiated and 33（78.57%） were poorly differentiated. Totally 15（35.71%） eyes had optic nerve（ON） tumor invasion, 36（85.71%） had choroidal tumor invasion, and 14（33.33%） had simultaneous choroidal and ON invasion. There was no statistically significant relationship between P-gp, GSTπ, LRP positivity and the degree of ocular layer tumor invasion and ON tumor invasion（P〉0.05）. CONCLUSION： RB intrinsically expresses GSTπ, P-gp and LRP. GSTπ expression is positive in 100% welldifferentiation ones, so in which way it is correlated with differentiation. But the other two proteins expressions are not related to tumor differentiation and to the degree of tumor invasion. GSTπ may be a new target of chemotherapy in RB.

Epidemiology and Rb 1 gene of retinoblastoma

Retinoblastoma (Rb) is the most common eye cancer in children and it can be inherited. Rb is quite rare and originators from the neural retina with a significant genetic component in etiology, which occurs in approximately 1 in every 20 0000 births. In children with the heritable genetic form of Rb, there is a mutation on chromosome 13, called the retinoblastoma 1 (Rb1) gene. Early diagnosis and intervention is critical to the successful treatment of the Rb. The Rb1 gene is the first cloned tumor suppressor gene. As a negative regulator of the cell cycle, Rb1 gene could maintain a balance between cell growth and development through binding to transcription factors and regulating the expression of genes involved in cell proliferation and differentiation. Thus, it is involved in cell cycle, cell senescence, growth arrest, apoptosis and differentiation. We summarized the recent advances on the epidemiology and Rb1 gene of Rb in this review.

Interaction among Rb/p16, Rb/E2F1 and HDAC1 Proteins in Gallbladder Carcinoma

The mechanism and interaction among Rb/p16, Rb/E2F1 and HDAC1 proteins in gallbladder carcinoma were investigated. By using the immunoprecipitation method, the interactions among Rb, p16, E2F1, HDAC1 proteins in gallbladder carcinoma cell line （Mz-ChA-1） were studied. It was found that there were Rb and E2F1 proteins in the precipitates with anti-HDAC1, and there were HDAC1 and E2F1 proteins in the precipitate with anti-Rb. It was concluded that there are specific interactions among Rb, HDAC1 and E2F1 proteins in gallbladder carcinoma, indicating the existence of the direct Rb/E2F1/HDAC1 signal transduction pathway. There is no direct relationship between p16 proteins with Rb, HDAC1, and E2F1 proteins.

Expression levels of autophagy related proteins and their prognostic significance in retinocytoma and retinoblastoma

·AIM: To discuss the prognostic significant of autophagy related proteins(ARPs) in retinoblastoma(RB)and to find the molecular marker to distinguish retinocytoma(RC) and RB by investigating the different expression profiling of microtubule-associated protein light chain 3(LC3B) and other ARPs in RC and RB.·METHODS: Specimens with retinocytoma region(RCR)or mainly composed with Flexner-Winterstein rosettes(FWR) were screen out from 219 paraffin-embedded RB samples and respectively taken as RCR group and FWR group. Others were taken as undifferentiated(UD) group.Immunochemistry(IHC) of LC3 B and electronic microscopy was used to identify autophagy. The IHC scores of LC3 B and other ARPs, such as Beclin, PTEN,p27, p16INK4 a, mTOR and BCL-2 were compared and correlation analysis was applied to find potential proteins which may involve in autophagy regulation. The prognostics significance of LC3 B was evaluated by comparing the high risk features(HRFs) in 3 groups of total 219 samples.·RESULTS: Twenty-one specimens with RCR and 36 specimens mainly composed with FWR were screen out.RCR cell had a high level of LC3 B and lots of autophagic vacuoles. Beclin, PTEN, p27 had positive correlation with LC3, and p16INK4 ahad negative correlation, while the expression of mTOR and BCL-2 in RCR and RB region did not show any difference. Cases with RCR had lower rate of HRFs than undifferentiated cases.·CONCLUSION: ARPs had different expression pattern between RCR and other pathological types of RB, and could be ideal markers to distinguish RC from RB. Our finding indicated cases with RCR had favorable prognosis just like those with FWR.

Association of cyclin D1, p16 and retinoblastoma protein expressions with prognosis and metastasis of gallbladder carcinoma

AIM: To investigate the role of cydin D1, p16 and retinoblastoma in cancerous process of gallbladder carcinomas and to assess the relation between cyclin D1, p16, Rb and the biological characteristics of gallbladder carcinoma.METHODS: Forty-one gallbladder carcinoma, 7 gallbladder adenoma and 14 chronic cholecystitis specimens were immunohistochemically and histopathologically investigated for the relation of cyclin D1, p16 and Rb with Nevin staging and pathologic grading.RESULTS: The expression rates of abnormal cyclin D1 in gallbladder carcinoma (68.3%)and gallbladder adenoma(57.1%) were significantly higher than those in chronic cholecystitis (7.1%) (P＜0.05). No significant difference was found both among the pathological grades G1, G2 and G3and among Nevin stagings S1-S2, S3 and S4-S5 of gallbladder carcinoma. The positive rates of p16 (48.8%) and Rb(58.5%) in gallbladder carcinoma were significantly lower compared to those in adenoma (100.0%) and cholecystitis(100.0%) (P＜0.05). The positive rates of p16 and Rb in Nevin stagings S1-S2 (80.0% and 90.0%) and S3 (46.2%and 61.5%) gallbladder carcinomas were significantly higher than those in S4-S5 (33.3% and 38.8%) (P＜0.05),and those in pathologic grades G1 (54.5% and 81.8%) and G2 (50.0% and 62.5%) gallbladder carcinoma were significantly higher than those in G3 (28.6% and 35.7%)(P＜0.05). The protein expression of p16 and Rb had a negative-correlation in gallbladder carcinoma (r = -0.2993,P＜0.05), and this negative-correlation was correlated with Nevin staging (P＜0.05). Moreover, the protein expression of p16 and cyclin D1 had a negative-correlation in gallbladder carcinoma (r = -0.9417, P＜0.05).CONCLUSION: Cyclin D1 may play a role in the early stage of gallbladder carcinoma. Mutation of p16 and Rb genes might be correlated with progression of gallbladder carcinoma.Analysis of p16 and Rb can estimate the prognosis of gallbladder carcinoma. Expression of p16 and Rb may be correlated with Nevin staging and pathologic grading in gallbladder carcinoma.

Expression of altered retinoblastoma protein inversely correlates with tumor invasion in gastric carcinoma

AIM: To investigate the clinical and pathological significance of altered retinoblastoma (Rb) encoding protein (pRb) in gastric carcinoma. METHODS: Expression of altered pRb was analyzed in 91 patients with gastric adenocarcinoma by immunohistochemistry. RESULTS: Sixty-five percent (59/91) of the tumors were positively stained and the staining in tumor nuclei of gastric carcinoma ranged 0%-90%. Moreover, strong expression of altered pRb was found in 35% (6/17), 24% (5/21), 17% (8/46) and 0% (0/7) of T1, T2, T3 and T4 gastric carcinomas, respectively. altered pRb expression was inversely correlated with the depth of tumor invasion (P = 0.047). Degree of immunoreactivity had no significant correlation with tumor grade, node metastasis and distant metastasis. In terms of prognostic significance, univariate analysis showed that poor differentiation [41 (66.1%) vs 34 (42.5%) P = 0.051], advanced tumor stage (P < 0.001) and weakly altered pRb expression [17 (80.5%) vs 58 (49.6%) P = 0.044] were associated with worse prognosis in these patients. However, multivariate analysis revealed that advanced tumor stage was the only independent poor prognostic factor (P < 0.001). CONCLUSION: The mutation of Rb gene is frequent in gastric carcinoma. The expression of altered pRb inversely correlates with tumor invasion and is not an independent prognostic marker in gastric adenocarcinoma.

EXPRESSION OF p16,CYCLIN D1 AND RB PROTEIN IN GASTRIC CARCINOMA AND PREMALIGNANT LESIONS

Objective: To investigate the expression of p16, cyclin D1 and Rb protein in gastric carcinoma and premalignant lesions including dysplastic gastric mucosa and intestinal metaplasia gastric mucosa. Methods: Using SP immunohistochemical methods, the expression of pl6, cyclin D1 and Rb proteins was detected in 10 specimens of normal gastric mucosa, 15 specimens of dysplastic gastric mucosa, 15 specimens of intestinal metaplasia gastric mucosa, 30 specimens of gastric carcinoma. The clinical characteristics of the 30 patients with gastric carcinoma were analysed to explore the relationship between the parameter detected and biological action of gastric cancer. Results: Expression of p16 protein was detected in 90% of normal gastric mucosa, 86.67% of dysplastic gastric mucosa, 86.67% of intestinal metaplasia gastric mucosa, 36.67% of gastric carcinoma. The positive rate of p16 protein expression in gastric carcinoma is significantly lower than that in normal gastric mucosa and gastric premalignant lesions mucosa (P<0.01). Expression of cyclin D1 protein was detected in 10% of normal gastric mucosa, 20% of dysplastic gastric mucosa, 20% of intestinal metaplasia gastric mucosa, 53.33% of gastric carcinoma. The positive rate of cyclin D1, protein expression in gastric carcinoma is significantly higher than that in normal gastric mucosa and gastric premalignant lesions mucosa (P<0.05). Expression of Rb protein was detected in 90% of normal gastric mucosa, 80% of dysplastic gastric mucosa, 80% of intestinal metaplasia gastric mucosa, 50% of gastric carcinoma. The positive rate of Rb protein expression in gastric carcinoma is significantly lower than that in normal gastric mucosa (P<0.05). The expression of p16, cyclin D1 gene were associated with the degree of differentiation of gastric carcinoma, lymphnodes metastasis and distant metastasis. Conclusion: p16, Cyclin D1 and Rb gene play important role in gastric carcinoma genesis. The expression of p16, cyclin D1 and Rb gene have some value to the diagnosis at earlier stage of gastric cancer. Detection of expression of p16, cyclin D1 gene would be helpful to judge the prognosis of gastric cancer.

Epidemiological aspect of retinoblastoma in the world: a review of recent advance studies

·AIM: To collect and present updated evidence about epidemiological aspects of retinoblastoma(Rb) in the world.·METHODS: A comprehensive search without the time and language restrictions was conducted in international databases, including MEDLINE, Scopus, Web of Science, and Pub Med. The search keywords were “retinoblastoma” OR “retinal Neuroblastoma” OR “retinal glioma” OR “retinoblastoma eye cancer” OR “retinal glioblastoma”.·RESULTS: The worldwide incidence of Rb is 1 in 16 000-28 000 live births, but was higher in developing compared to developed countries. Several attempts for improving early detection and treatment had increased the Rb survival rate from 5% to 90% in developed countries over the past decade, but its survival was lower in developing countries(about 40% in low-income countries) and the majority of mortalities occurred in developing countries. The etiology of Rb could be viewed as genetics in the heritable form and environmental and lifestyle factors in the sporadic form. Some environmental risk factors such as in vitro fertilization;insect sprays;father’s occupational exposure to oil mists in metal working, and poor living conditions might play a role in the occurrence of the disease. Although ethnicity might affect Rb incidence, sex has no documented effect and the best treatment approaches were now ophthalmic artery chemosurgery and intravitreal chemotherapy.·CONCLUSION: Determining the role of genetics and environmental factors helps to accurately predict the prognosis and identify the mechanism of the disease, which can reduce the risk of tumor development.

棕榈酸酯通过调控p16INK4a/Rb信号通路诱导AC16人心肌细胞发生衰老表型改变

目的探讨棕榈酸酯(palmitic acid,PA)在AC16人心肌细胞衰老表型改变中的作用及机制。方法AC16细胞分为(1)对照组PA浓度(0.08、0.19、0.3、0.8 mmol/L)组;(2)对照组,时间(24、36、48、72 h)刺激组。细胞计数试剂盒-8法测细胞总体活性,流式细胞术测细胞周期;活性氧(reactive oxygen species,ROS)试剂盒测细胞内ROS水平;β-半乳糖苷酶(SA-β-Gal)染色测染色阳性细胞率;酶联免疫吸附测定法(enzyme-linked immuno⁃sorbent assay,ELISA)测衰老相关分泌表型(senescence-associated secretory phenotype,SASP)相关因子白细胞介素(interleukin,IL)-1A、IL-6、IL-8和干扰素(interferon,IFN)-γ浓度;实时定量聚合酶链反应(quantitative real time polymerase chain reaction,qRT-PCR)及Western blot测SASP及p16^(INK4a)/视网膜母细胞瘤抑制蛋白(retinoblasto⁃ma protein,Rb)通路表达。为观察p16^(INK4a)/Rb通路对心肌衰老表型影响,细胞分为4组:对照组、PA组、si-con组和si-p16^(INK4a)组,qRT-PCR测p16^(INK4a) mRNA表达;Western blot测p16^(INK4a)、p-Rb、Rb及IL-1A、IFN-γ蛋白表达;β-半乳糖苷酶染色测阳性细胞率。结果随PA浓度及刺激时间增加,细胞活性不断下降,差异有统计学意义(P<0.05)。与对照组相比,0.19 mmol/L PA组在G1期比例显著升高,S期显著降低,差异有统计学意义(P<0.05)。0.08~0.3 mmol/L PA组ROS水平高于对照组,PA组中β-半乳糖苷酶染色阳性率均高于对照组,差异有统计学意义(P<0.05)。0.19 mmol/L PA组IL-1A、IL-6、IL-8、IFN-γ浓度显著高于对照组,差异有统计学意义(P<0.05)。0.19 mmol/LPA组IL-1A、IL-6、IL-8、IFN-γ及p16^(INK4a)、Rb mRNA及蛋白表达明显高于对照组,而p-Rb蛋白表达下降,差异有统计学意义(P<0.05)。si-p16^(INK4a)组IL-1A、IFN-γ蛋白表达及SA-β-Gal阳性率低于si-con组,差异有统计学意义(P<0.05)。结论0.19 mmol/L PA可能通过调控p16^(INK4a)/Rb通路诱导人心肌细胞衰老表型改变。

Genetic Predisposition to Retinoblastoma (Rb)

Determination of 8 cytogenetic indicators in 14 cases of Rb,their 21 parents and 14 normal controls revealed various degrees ofchromosome instability and nondisjunction in the patients and their parents,indicating the presence of genetic neoplastic predisposition to neoplasm inRb patients.Eye Science 1993;9:149-152.

Expression of multidrug resistance proteins in retinoblastoma

AIM： To elucidate the mechanism of multidrug resistance in retinoblastoma, and to acquire more insights into in vivo drug resistance.METHODS： Three anticancer drug resistant Y79 human RB cells were generated against vincristine, etoposide or carboplatin, which are used for conventional chemotherapy in RB. Primary cultures from enucleated eyes after chemotherapy（PCNC） were also prepared. Their chemosensitivity to chemotherapeutic agents（vincristine, etoposide and carboplatin） were measured using MTT assay. Western blot analysis was performed to evaluate the expression of p53, Bcl-2 and various multidrug resistant proteins in retinoblastoma cells.RESULTS： Following exposure to chemotherapeutic drugs, PCNC showed less sensitivity to drugs. No significant changes observed in the p53 expression, whereas Bcl-2 expression was found to be increased in the drug resistant cells as well as in PCNC. Increased expression of P-glycoprotein（P-gp） was observed in drug resistant Y79 cells; however there was no significant change in the expression of P-gp found between primary cultures of primarily enucleated eyes and PCNC. Multidrug resistance protein 1（Mrp-1） expression was found to be elevated in the drug resistant Y79 cells as well as in PCNC. No significant change in the expression of lung resistance associatedprotein（Lrp） was observed in the drug resistant Y79 cells as well as in PCNC.CONCLUSION： Our results suggest that multidrug resistant proteins are intrinsically present in retinoblastoma which causes treatment failure in managing retinoblastoma with chemotherapy.

视网膜母细胞瘤细胞系HXO-Rb_(44)抑癌基因的表达

目的检测视网膜母细胞瘤（ＲＢ）细胞系ＨＸＯＲｂ４４中抑癌基因Ｒｂ的表达状况，为进一步研究ＲＢ的发病机制，利用抑癌基因Ｒｂ进行ＲＢ的基因治疗提供实验依据。方法用ＳＰ免疫组织化学（ＩＨＣ）及流式细胞术（ＦＣＭ）间接免疫荧光法对Ｒｂ基因的表达进行定性、形态学定位及定量检测。结果ＩＨＣ法检测显示：正常视网膜组织中Ｒｂ蛋白呈阳性反应，位于细胞核呈棕黄色；ＨＸＯＲｂ４４中Ｒｂ蛋白表达阴性。ＦＣＭ检测显示：正常人淋巴细胞Ｒｂ蛋白表达量是ＨＸＯＲｂ４４细胞的３．７１倍，ＨＸＯＲｂ４４中Ｒｂ蛋白表达量极低。结论ＲＢ细胞系ＨＸＯＲｂ４４中存在野生型Ｒｂ基因的功能失活，Ｒｂ基因的突变失活与ＲＢ的发生密切相关。

Rb基因诱导视网膜母细胞瘤移植瘤细胞凋亡的实验研究

目的观察外源性Ｒｂ基因对视网膜母细胞瘤（ＲＢ）细胞凋亡的影响。方法建立裸鼠眼玻璃体腔ＲＢ移植瘤模型及构建Ｒｂ基因的逆转录病毒表达载体Ｐｂａｂｅ－Ｒｂ，用脂质体Ｄｏｓｐｅｒ介导法将Ｒｂ基因导入裸鼠ＲＢ移植瘤，采用流式细胞术（ＦＣＭ），光镜、电镜及ＴＵＮＥＬ细胞凋亡原位末端标记法进行ＲＢ细胞凋亡的检测。结果Ｒｂ基因在ＲＢ移植瘤内表达至少持续７天。ＦＣＭ检测发现在Ｒｂ基因转染后第４天，各实验组治疗眼ＲＢ中均可检测到凋亡细胞峰，凋亡细胞百分率高于对照眼；第２０天，各实验组治疗眼细胞凋亡百分率与对照眼比无差异（Ｐ＞０．０５）。透射电镜下可见到典型的早期凋亡细胞及晚期凋亡小体形成。ＴＵＮＥＬ方法可在荧光显微镜下见到发黄绿色荧光的凋亡细胞，光镜下可见到紫红色的被标记的凋亡细胞。结论Ｒｂ基因可诱导ＲＢ移植瘤细胞凋亡，这可能是Ｒｂ基因体内抗癌的又一作用机制。

MCM2和Rb蛋白在胃癌中的表达及临床意义

目的:探讨微小染色体维持蛋白2(MCM2)和视网膜母细胞瘤易感基因(Rb)在胃癌组织中的表达及其意义。方法:采用免疫组化法检测MCM2和Rb蛋白在20例正常胃黏膜、30例非典型增生、80例胃癌组织中的表达,并以标记指数(labellingindex,LI)量化其表达。结果:MCM2和Rb蛋白在正常胃黏膜、非典型增生和胃癌组织中的表达之间均有显著性差异(P<0.05);两者的LI在胃癌组织中表达与临床分期、浆膜浸润、术后复发、肝转移及淋巴结转移密切相关(P<0.05),与肿瘤大小及组织学类型无关(P>0.05)。胃癌组织中MCM2和Rb的LI表达呈显著负相关(r=-0.321,P=0.004)。结论:MCM2表达升高和Rb蛋白表达下降与胃癌的发生及发展密切相关,检测MCM2和Rb有助于判断胃癌恶性程度及预后。

大肠癌组织中CyclinD1和p16及Rb的表达及其临床意义

目的:探讨细胞周期调控因子在大肠癌组织中的表达及其与大肠癌临床病理特征的关系。方法:应用免疫组化SP法对70例大肠癌组织及距癌灶3cm以外的癌旁组织和10cm以外的正常组织中CyclinD1、p16和Rb进行检测。结果:CyclinD1在大肠癌中过度表达为51.4%(36/70),并与肿瘤分化程度呈反比,有淋巴结转移的大肠癌,CyclinD1阳性率为70.0%,无淋巴结转移的大肠癌阳性率为44.0%,两者相比差异有统计学意义(P=0.049)。p16在大肠癌中为低表达47.1%(33/70),癌旁组织和正常组织中p16的表达分别为57.1%和71.4%。Rb在大肠癌、癌旁及正常组织中的表达分别为65.7%、78.6%和85.7%。CyclinD1与p16表达呈负相关(P=0.000,r=-0.514),p16与Rb表达呈负相关(P=0.001,r=-0.403)。结论:CyclinD1过度表达与肿瘤的分化程度、淋巴结转移密切相关;p16表达可能受Rb蛋白的负调控;CyclinD1过度表达和p16低表达在大肠癌发生中起协同作用;大肠癌发生机制涉及CyclinD1、p16和Rb调节环路中多个基因的异常。

Rb和MCM2蛋白在前列腺癌中的表达及临床意义

目的:探讨视网膜母细胞瘤易感基因(Rb)和微染色体维持蛋白2(MCM2)在前列腺癌发病机制中的作用及其临床意义。方法:应用免疫组化EliVisionTM plus二步法,检测49例前列腺癌(PCa)组织,20例良性前列腺增生(BPH)及10例正常前列腺组织(NP)中pRb蛋白与M CM 2的表达。结果:pRb在PCa,BPH与NP组织中的阳性表达率分别为44.90%,80%,90%,PCa中pRb的水平明显低于BPH(P<0.05)及NP(P<0.05),且与PCa病理分级(P<0.05)和临床分期(P<0.05)呈负相关。M CM 2在PCa,BPH与NP组织中的阳性表达率分别为67.35%,25%和10%,PCa中M CM 2的水平明显高于BPH(P<0.05)及NP(P<0.05),且与PCa病理分级(P<0.05)和临床分期(P<0.05)呈正相关。M CM 2表达与pRb表达呈负相关(rs=-0.596,P<0.01)。结论:Rb基因参与了前列腺癌的发生、发展过程,检测Rb基因和M CM 2有助于判定前列腺癌恶性程度及预后。

p16和Rb基因蛋白在肺癌中的表达

目的：研究ｐ１６和Ｒｂ基因蛋白的表达与肺癌临床病理学特征的关系。方法：采用免疫组织化学方法对８９例肺癌进行了ｐ１６和Ｒｂ蛋白的定位观察。结果：肺癌ｐ１６基因蛋白的总丢失率为４７２％（４２／８９），且与肺癌的组织学类型、淋巴结转移、临床病理分期有关。Ｒｂ基因蛋白的总丢失率为３１５％（２８／８９），与组织学类型有关。ｐ１６和Ｒｂ基因蛋白的表达存在着明显的互补性。结论：ｐ１６和Ｒｂ基因蛋白的丢失是肺癌发生发展中重要的分子事件，与细胞周期Ｇ１→Ｓ期的负反馈调节环路中断关系密切。