p21cip1和p27kip1基因遗传多态与食管癌及贲门癌发病风险的关联

背景与目的：有研究表明p21^cip1和p27^kip1的基因多态性与乳腺癌、肺癌、前列腺癌等肿瘤易感性有关。本研究分析中国北方高发区人群食管鳞状细胞癌（ESCC）和贲门腺癌（GCA）与勺p21^cip1和p27^kip1基因多态性之间的关系。方法：应用聚合酶链反应-限制性片段长度多态性（PCR—RFLP）方法检测299例ESCC患者、256例GCA患者及437名健康对照人群p21^cip1 3’非翻译区和p27^kip1第109位密码子基因多态性分布情况。结果：ESCC患者组p21^cip1 T等位基因型频率（42．8％）显著高于健康对照组（36．7％）（P=0．02）,ESCC和GCA患者组p27^kip1等位基因型频率（分别为96．8％和96．1％）均显著高于健康对照组（92．9％）（P值分别为0．00和0．02）。ESCC患者组p21^cip1基因型频率分布与健康对照组相比有显著性差异（P=0．04）,与C／C和C／T基因型相比,T／T基因型可显著增加ESCC的发病风险（校正OR=1．93,95％CI=1．12～3．94）ESCC和GCA患者细p27^kip1基因型频率分布与健康对照组相比均有显著性差异（P分别为0．00和0．01）,与V／G和G／G基因型相比,V／V基因型可显著增加ESCC和GCA的发病风险（校正OR分别为2．44和2．01,95％CI分别为1．2l～4．02和1.12～3．68）。当按吸烟和上消化道肿瘤家族史状况进行分层分析时发现,与V／G和G／G基因型相比,V／V基因型可显著增加吸烟人群患ESCC和GCA（校正OR分别为2．24和2．61,95％C1分别为1.14～4．03和1．25～3．82）以及有家族史人群患ESCC的发病风险（校正OR=2．04,95%CI=1．04～3．43）．两基因联合分析显示,携带p21^cip1T／T和p27^kip1V／V基因型可显著增加患食管癌和贲门癌的发病风险（校正OR分别为3．78和2．56,95?分别为1．46～5．89和1．06～4．78）。结论：在中国北方人群中,p21^cip1基因多态性可能与食管癌的易感性有关,p27^kip1基因多态性可能与食管癌和贲门癌的易感性有关．而且这两个基因的多念性可能存食管癌和贲门癌发病中起联合作用．     

p16基因C540G和C580T多态与高发区食管癌和贲门癌发病风险的关联

目的探讨p16基因第3外显子3’端非编码区C540G和C580T两个单核苷酸多态与河北省高发区食管鳞状细胞癌（ESCC）和贲门腺癌（GCA）遗传易感性的关系。方法采用聚合酶链反应-限制性片段长度多态性（PCR—RFLP）方法分析265例ESCC患者、238例CA;A患者和246名健康对照的p16基因C540G和C580T多态位点的基因型。结果p16基因C540G三种基因型（C／C、C／G、G／G）的频率分布在ESCC、GCA患者和对照组相比均无显著差异;p16基因C580T三种基因型（C／C、C／T、T／T）的频率在对照组和ESCC、GCA患者组间也无显著差异（P均〉0．05）。单体型分析显示,对照组540C／580C、540C／580T、540G／580C和540G／580T单体型的频率分别为80．1％、10．4％、8．5％和1．0％,ESCC组单体型频率（80．8％、9．6％、8．7％和0．9％）和GCA组的单体型频率（80．2％、9．2％、9．5％和1．1％）与之相比均无显著差异（P均〉0．05）。结论p16基因C540G和C580T多态可能与河北省高发区ES-CC和GCA的易感性无关。     

β1-5090／T基因多态性与中国人群NSOLC遗传易感相关性的研究

目的：探讨转化生长因子β1基因（TGF-β1）-509C／T位点多态性与中国人群非小细胞肺癌（non-small cell lung cancer,NSCLC）遗传易感性的关系。方法：采用聚合酶链反应-限制性片段长度多态性PCR—RFLP方法检测210例NSCLC患者和208例健康对照者的TGF-β1—509C／T基因型分布,并分析两组之间的差异。结果：TGF—β1—509CT＋TT基因型相对于CC基N型是NSCLC发生的独立危险因素（P=0．007,OR=2．297,95％CI：1．250-4．219）;携带T等位基因者患NSCLC的风险是携带C等位基因者的1．617倍（P=0．001,95％CI：1．210～2．161）;重度吸烟者相对于不吸烟和轻度吸烟者是NSCLC发生的独立危险因素（P=0．021,OR=1．783,95％CI：1．089～2．918）。结论：TGF-β1—509C／T位点多态性在中国人群中与NSCLC遗传易感性相关,可作为NSCLC发病风险评估的筛选指标。     

XRCC2基因多态性与肺癌易感性关系的研究

目的：探讨中国北方人群中XRCC2基因C41657T、G4234C多态性与肺癌的关系。方法：应用PCR-RFLP方法检测199例肺癌患者和200例正常人的XRCC2 C41657T及G4234C多态位点，比较两组之间等位基因及基因型频率分布及其与肺癌的关系。结果：肺癌患者XRCC2 C41657T多态位点的CC、CT、TT基因型和C、T等位基因频率分布与健康对照组相比差异均无统计学意义（P〉0．05）。G4234C多态位点的GG、GC、CC基因型和G、C等位基因频率分布与健康对照组相比差异也均无统计学意义（P〉0．05）。两多态性位点联合分析显示，肺癌患者与健康对照组的4个单体型分布亦无统计学差异（P〉0．05）。以病理类型、吸烟状况和年龄进行分层分析显示，XRCC2 C41657T多态位点可能与腺鳞癌和不吸烟人群的肺癌发病风险相关；与C／C基因型相比，携带T等位基因的基因型（C／T＋T／T）可显著增加腺鳞癌的发病风险（OR为2．95，95％CI=1．15—7．59）；而C／T基因型可显著增加不吸烟组人群中肺癌的发病风险（OR为2．12，95％CI=1．05-4．27）。对于XRCC2 G4234C多态位点，与G／G基因型相比，G／C基因型和携带C等位基因的基因型（G／C＋C／C）可显著增加小细胞肺癌的发病风险（OR为2．82和2．82；95％CI=1．15～6．91和1．17～6．76）；G／C基因型或与C／C基因型相加可显著增加年龄≥60岁的人群中肺癌的发病风险（OR为2．29和2．37；95％CI=1．11—4．72和1．16—4．88）。结论：对于XRCC2 C41657T多态位点，携带T等位基因的基因型可能增加腺鳞癌的发病风险，C／T基因型可能增加不吸烟者患肺癌风险；XRCC2 G4234C多态位点，G／C基因型或携带C等位基因可能增加小细胞肺癌的发病风险和老年人（年龄≥60岁）患肺癌的风险。     

XPC 基因 rs2228000（C/T）多态性与乳腺癌易感性的Meta分析

目的：定量探讨着色性干皮病 C 组（XPC）基因 rs2228000（C ／T）多态性与乳腺癌易感性之间的关系。方法通过计算机检索 PubMed、Cochrane Library、中国生物医学文献数据库（CBM）、万方医药期刊全文数据库、中国期刊全文数据库（CNKI）及维普数据库（VIP）,检索时间截至2015年12月,搜集有关 XPC rs2228000（C ／T）位点多态性与乳腺癌风险的病例对照研究。采用 STATA 12．0软件进行结果分析,计算比值比（OR）和95％CI。结果总共纳入8篇文献,包括9个病例对照研究（3850例乳腺癌患者和5047例健康对照）。纯合子模型（TT vs．CC：OR ＝1．28,95％CI 为1．08～1．52,Z ＝2．80, P ＝0．005）和隐性模型（TT vs．TC ＋CC：OR ＝1．23,95％CI 为1．05～1．43,Z ＝2．64,P ＝0．008）中 XPC rs2228000（C ／T）多态性与乳腺癌易感性有关,而等位基因模型、杂合子模型、显性基因模型中 XPC rs2228000（C ／T）位点多态性与乳腺癌风险无关（P ＞0．05）。在亚洲人群和 PCR-RFLP 亚组的4种基因模型中,XPC rs2228000（C ／T）多态性与乳腺癌易感性有关（T vs．C：OR ＝1．21,95％CI 为1．05～1．40, Z ＝2．63,P ＝0．009;TT vs．CC：OR ＝1．55,95％CI 为1．13～2．13,Z ＝2．70,P ＝0．007;TT ＋TC vs．CC：OR ＝1．26,95％CI 为1．02～1．55,Z ＝2．19,P ＝0．028;TT vs．TC ＋CC：OR ＝1．39,95％CI 为1．04～1．87, Z ＝2．23,P ＝0．026）。基于对照组来源的亚组分析,社区来源的纯合子模型中 XPC rs2228000（C ／T）多态性与乳腺癌发病风险有关（TT vs．CC：OR ＝1．27,95％CI 为1．02～1．57,Z ＝2．16,P ＝0．031）。结论XPC rs2228000（C ／T）多态性可能与乳腺癌风险有关,尤其在亚洲人群中,基因型 TT 可能增加乳腺癌发病风险。     

XPC基因Ala499Val、Lys939Gln多态与食管癌、贲门癌发病风险的关联

背景与目的：XPC基因参与核苷酸切除修复,该基因存在单核苷酸多态性（SNP）位点,并可能通过SNP位点碱基的改变影响其修复能力及疾病易感性。本研究旨在探讨XPC基因第8外显子Ala499Val及第15外显子Lys939G1nSNP与河北省食管癌、贲门癌高发区-磁县和涉县人群食管鳞状细胞癌（esophageal sguamous cell carcinoma,ESCC）和贲门腺癌（gastric cardiac adenocorcinoma,GCA）遗传易感性的关系。方法：采用聚合酶链反应-限制性片段长度多态性（PCR—RFLP）分析方法检测327例ESCC患者、253例GCA患者和612名健康对照的XPC基因第8外显子Ala499Val及第15外显子Lys939Gln SNP的基因型。结果：ESCC患者组、GCA患者组上消化道肿瘤家族史阳性个体比例明显高于对照组,上消化道肘t瘤家族史可增加ESCC、GCA的发病风险（经性别和年龄校正后的OR=1．76和1．77．95％CI=1．34～2．32和1．31～2．39）.ESCC患者组和对照组的XPC基因第8外显子C、T等位基因频率及C／C、C／T、T／T基因型分布差异均无显著性（P〉0．05）。GCA患者组T等位基因频率（26．5％）显著低于对照组（32．5％）,两组相比差异有显著性（x^2=6．12,P=0．01）;与C／C基因型相比,携带C／T基因型可显著降低GCA的发病风险（OR=0．62,95％CI=0．45～0．84）。根据吸烟状况和上消化道肿瘤家族史进行分层分析发现,与C／C基因型相比,携带C／T基因型可显著降低吸烟个体和家族史阴性个体GCA的发病风险（OR均等于0．57,95％CI=0．36～0．91和0．37～0．88）。在ESCC、GCA患者组和对照组之间,XPC第15外显子A、C等位基因频率及A／A、A／C、C／C基因型分布差异均无显著性（P〉0．05）。根据吸烟状况和上消化道肿瘤家族史进行分层分析发现,与A／A基因型相比,携带C／C基因型可显著增加非吸烟个体ESCC的发病风险（OR=2．05,95％CI=1．15～3．66）。单体型分析显示,A／T、A／C、C／T、C／C四种单体型,在ESCC患者组与对照组之间分布差异无显著性（P〉0．05）;在GCA患者组与对照组之间分布差异有显著性（P=0．02）。与A／T单体型相比,携带A／C、C／C单体型可显著增加GCA的发病风险（OR=1．35和1．46,95％CI=1．01～1．81和1．06～2．00）。结论：在河北省食管癌、贲门癌高发区一磁县和涉县人群中,携带XPC基因第8外显子C／T基因型可能明显降低GCA的发病风险;第15外显子Lys939Gln SNP可能与ESCC、GCA的发病风险无关,但分层分析发现携带第15外显子C／C基因型可能增加非吸烟个体ESCC的发病风险;携带A／C、C／C单体型可能增加GCA的发病风险。     

p53基因BstUⅠ位点多态性与非小细胞肺癌易感性及放射敏感性的相关性研究

背景与目的肺癌是世界上发病率和死亡率增长较快的恶性肿瘤。近几年来随着分子生物学的蓬勃发展，人们对疾病的认识达到了基因水平。通过分子生物学方法发现某一基因与肺癌之间的关联性并加以利用，为早期诊断及治疗肺癌提供了一个新的思路。本研究拟探讨p53肿瘤抑制基因BstUⅠ位点多态性与非小细胞肺癌（NSCLC）易感性及放射敏感性的相关性。方法采用PCR-RFLP方法检测50例NSCLC患者及50例健康对照p53基因序列中的BstUⅠ位点单核苷酸多态性（SNP）。并采用病例对照方法分析p53基因BstUⅠ位点的多态性与肺癌的易感性，以及NSCLC患者p53基因BstUⅠ位点的多态性与放疗疗效的相关性。结果不同p53基因BstUⅠ基因型的NSCLC患者对放疗的有效率不尽相同。杂合子（A1／A2）基因型的患者对放疗的有效率低．仅为25．0％，而纯合子（A1／A1，A2／A2）基因型的患者对放疗的有效率较高，分别为71．4％和70．0％，三者之间的差异有显著性（χ^2=9．2，P〈0．05）。肺癌组的A1／A1、A1／A2及A2／A2基因型频率分别为28．0％、32．0％及40．0％，对照组为32．0％、42．0％及26．0％，但两组间纯合子的频率差异并无统计学意义（P均〉0．05），并且未观察到p53基因BstUⅠ的多态性与NSCLC易感性有密切的相关关系。结论p53基因BstUⅠ位点多态性可能与NSCLC发生无关，但NSCLC患者的p53基因BstUⅠ SNP可能与放射敏感性有关。     

IL-27基因多态性和血清 IL-27 p28水平与骨肉瘤风险相关性分析

目的：评估IL-27基因多态性和血清IL-27p28水平与骨肉瘤风险的相关性。方法对比研究160例骨肉瘤患者（研究组）和250例健康患者（对照组）。 IL-27基因-964 A／G，2905 T／G，和4730 T／C多态性采用聚合酶链反应-限制性片段长度多态性测定。酶联免疫吸附试验检测血清中IL-27p28的水平。结果与对照组相比，骨肉瘤患者血清IL-27p28水平显著降低（P＜0．01）。Ⅲ～Ⅳ期骨肉瘤患者血清IL-27p28水平低于Ⅰ～Ⅱ期患者（P＜0．05）。同样，转移患者的血清IL-27p28水平低于非转移患者（ P＜0．05）。 IL-27-964 A／G，2905 T／G，4730 T／C的基因型和等位基因频率与骨肉瘤风险无相关性（ P＞0．05）。分层分析也未能显示-964 A／G，2905 T／G，和4730 T／C多态性与临床分期和骨肉瘤的转移存在相关性（P＞0．05）。结论血清IL-27p28低水平可能与骨肉瘤进展有关，但IL-27基因-964 A／G，2905 T／G，和4730 T／C多态性和它们的单倍型不与骨肉瘤的风险相关联。     

基质金属蛋白酶1、9基因多态性与成人脑星形细胞瘤的易感性

 目的本研究旨在探索MMP-1、MMP-9基因启动子区单核苷酸多态性（Singlenucleotidepoly—morphism，SNPs）与脑星形细胞瘤易感性的关系。方法以聚合酶链反应一限制性片段长度多态性分析方法，检测236例成人星形细胞瘤及366例健康对照的MMP．1-16072G／1G及MMP-9-1562C／T多态性的基因型。结果（1）MMP-1—16072G／1GSNP等位基因型及基因型总体分布在星形细胞瘤患者组和健康对照组之间有显著性差异（P值分别为0．002和〈0．001）。与2G／2G基因型相比，1G／1G基因型可显著降低该肿瘤的发病风险（校正OR=0．58，95％CI=0．42～O．79），而2G／1G基因型对该肿瘤的易感性无显著影响（校正OR=0．74，95％CI=0．51～1．08）。根据性别、发病年龄（≤45岁或〉45岁）进行的分层分析显示了相似的结果。（2）MMP-9-1562C／T的等位基因型及基因型总体分布在肿瘤患者组和健康对照组之间差异无统计学意义（P值分别为0．926和0．818）。与C／C基因型相比，C／T＋T／T基因型不能改变星形细胞瘤的发病风险（校正OR=1．09，95％CI：0．73～1．64）。根据性别、发病年龄、病理分级进行的分层分析，也未发现MMP-9SNP与星形细胞瘤的发病风险相关。结论MMP-1—16072G／1G多态性与星形细胞瘤的易感性有关，而MMP-9—1562C／T多态性可能不是该肿瘤的独立易感因素。     

亚甲基四氢叶酸还原酶基因型、饮食习惯与胃癌的易感性

目的：研究亚甲基四氢叶酸还原酶（MTHFR）基因C677T多态性、饮食习惯与胃癌易感性的关系。方法：在上消化道癌高发区淮安市楚州区进行了一个病例－对照研究（胃癌107例，人群对照200例），调查研究对象的生活习惯，用PCR－RFLP技术检测研究对象的MTHFR基因型。结果：（1）胃癌组中MTHFR C／T或T／T型基因携带者占79．4％，显著高于对照组的68．5％（χ^2=4.15,P=0.0416,OR=1.78,95% CI:0.99-3.22;调整OR＝1．79，95％CI：1．01－3．19）。（2）在不经常吃大蒜、大葱者中，MTHFR C／T或T／T型基因携带者发生胃癌的危险性显著升高。在不饮茶者中或在经常吃肉者中，携带MTHFRC／T或T／T型基因者发生胃癌的危险性也显著上升。结论：MTHFR C677T基因型与胃癌的易感性有关；不同饮食习惯对MTHFR C677T基因型与胃癌易感性之间的关系有影响。     

p53-dependent and p53-independent anticancer effects of different histone deacetylase inhibitors

Background:

Histone deacetylase inhibitors (HDACi) are promising antineoplastic agents, but their precise mechanisms of actions are not well understood. In particular, the relevance of p53 for HDACi-induced effects has not been fully elucidated. We investigated the anticancer effects of four structurally distinct HDACi, vorinostat, entinostat, apicidin and valproic acid, using isogenic HCT-116 colon cancer cell lines differing in p53 status.

Methods:

Effects were assessed by MTT assay, flow-cytometric analyses of propidium iodide uptake, mitochondrial depolarisation and cell-cycle distribution, as well as by gene expression profiling.

Results:

Vorinostat was equally effective in p53 wild-type and null cells, whereas entinostat was less effective in p53 null cells. Histone deacetylase inhibitors treatment suppressed the expression of MDM2 and increased the abundance of p53. Combination treatments showed that vorinostat enhanced the cytotoxic activity of TRAIL and bortezomib, independent of the cellular p53 status. Investigations into the effects of an inhibitor of the sirtuin class of HDAC, tenovin-1, revealed that tenovin-1-mediated cell death hinged on p53.

Conclusion:

These results demonstrate that vorinostat activates p53, but does not require p53 for inducing its anticancer action. Yet they also demonstrate that entinostat-induced cytotoxic effects partially depend on p53, indicating that different HDACi have a different requirement for p53.     

Chromosome 9p21 gene copy number and prognostic significance of p16 in ESFT

Chromosome 9p21 gene copy number in Ewing's sarcoma family of tumour (ESFT) cell lines and primary ESFT has been evaluated using Multiplex Ligation-dependent probe amplification, and the clinical significance of CDKN2A loss and p16/p14(ARF) expression investigated. Homozygous deletion of CDKN2A was identified in 4/9 (44%) of ESFT cell lines and 4/42 (10%) primary ESFT; loss of one copy of CDKN2A was identified in a further 2/9 (22%) cell lines and 2/42 (5%) tumours. CDKN2B was co-deleted in three (33%) cell lines and two (5%) tumours. Co-deletion of the MTAP gene was observed in 1/9 (11%) cell lines and 3/42 (7%) tumours. No correlation was observed between CDKN2A deletion and clinical parameters. However, co-expression of high levels of p16/p14(ARF) mRNA predicted a poor event-free survival (P=0.046, log-rank test). High levels of p16/p14(ARF) mRNA did not correlate with high expression of p16 protein. Furthermore, p16 protein expression did not predict event-free or overall survival. Methylation is not a common mechanism of p16 gene silencing in ESFT. These studies demonstrate that loss (homozygous deletion or single copy) of CDKN2A was not prognostically significant in primary ESFT. However, high levels of p16/p14(ARF) mRNA expression were predictive of a poor event-free survival and should be investigated further.     

大肠小扁平腺瘤内镜和组织学特征及p53、p21表达研究

[目的]探讨大肠小扁平腺瘤的形态学特征及p53、p21表达的生物学意义。[方法]①用电子结肠镜及光学显微镜观察50例大肠小扁平腺瘤形态学特征。②用免疫组化二步法检测50例小扁平腺瘤及对照组26例大肠癌、15例正常人大肠黏膜中p53、p21表达率。[结果]①小扁平腺瘤发生于大肠任何部位．其发病率依次以横结肠、乙状结肠、直肠为多见；肠镜下见病灶呈圆形或椭圆形，扁平状，基底宽，体积〈1cm。②光镜下小扁平腺瘤呈管状腺瘤样图像，上皮具有不同程度的异型增生。⑧小扁平腺瘤中p53、p21的表达率分别为58％（29／50）、56％（28／50）。随着小扁平腺瘤异型增生程度的增高．p53、p21的表达率也逐渐升高（P〈0．05）。p53、p21在正常肠黏膜、小扁平腺瘤及大肠癌组中阳性表达率均逐渐升高，三组问差异有显著性（P〈0．05）。[结论]大肠小扁平腺瘤有其独特的形态学特征，p53、p21的表达与大肠小扁平腺瘤的癌变发生发展有密切关系。     

Genomic instability, mutations and expression analysis of the tumour suppressor genes p14(ARF), p15(INK4b), p16(INK4a) and p53 in actinic keratosis

Actinic keratosis (AK) is a well-established pre-cancerous skin lesion that has the potential to progress to squamous cell carcinoma (SCC). We investigated the involvement of the CDKN2A, CDKN2B and p53 genes in AK and in the progression of AK to SCC. Mutational analysis on exons 1a, 1b and 2 of the CDKN2A locus and exon 1 of the CDKN2B locus as well as allelic imbalance was performed in 26 AK specimens. Expression levels of the genes p14(ARF), p15(INK4b), p16(INK4a) and p53 were examined in 16 AKs and 12 SCCs by real-time RT-PCR. A previously described polymorphism of p16(INK4a) (Ala148Thr) was detected at an allelic frequency of 12%. Six samples carried novel mutations at codon 71 of the CDKN2A locus and one sample presented an additional mutation at codon 65. Two AK samples carried a not-previously described non-UV type missense mutation at codon 184 (Val184Glu) of exon 1b in the p14(ARF) gene. Regarding the CDKN2B locus a new mutation at codon 50 (Ala50Thr) and another at codon 24 (Arg24Arg), were detected. Microsatellite instability (MSI) was found in 15% of AKs in at least one marker, indicating that genetic instability has some implication in the development of AK. Down-regulation of p16(INK4a) and p53 mRNA levels was noted in SCC compared to AK. TSGs expression levels in sun-exposed morphologically normal-appearing skin, suggests that abnormal growth stimuli might exist in these tissues as well. Furthermore, we suggest a possible role of p15(INK4b), independently from the intracellular pathway mediated by p16(INK4a), and of p14(ARF) in AK development, as well as in the progression of AK to SCC. The deregulation of the expression profiles of the CDKN2A, CDKN2B and p53 genes may, independently of mutations and LOH at 9p21, play a significant role in AK and progression of AK to SCC.     

Interplay among BRAF, p16, p53, and MIB1 in pediatric low-grade gliomas

BRAF rearrangements and BRAF V600E point mutations are recurring events in pediatric low-grade gliomas. However, their clinical significance, including possible interactions between these markers and other glioma biomarkers, is unclear. In this study a retrospective cohort of 198 pediatric low-grade gliomas (including 40 treated with adjuvant therapy) was analyzed for BRAF rearrangements, BRAF V600E, p16/CDKN2A deletion, p53 expression, and MIB1 proliferation index. In tumors with BRAF rearrangement, homozygous p16 deletion correlated with shorter progression-free survival (P = .04). A high MIB1 proliferation index trended toward worse response to adjuvant radiotherapy compared to BRAF-rearranged, p16-intact tumors (P = .08). On multivariate analysis, the 2 most consistently powerful independent adverse prognostic markers were midline location (P = .0001) and p16 deletion (P = .03). Tumors with BRAF V600E had a strong trend toward an increased risk for progression (hazard ratio = 2.48, P = .07), whereas those with BRAF rearrangement had a milder trend toward reduced risk (hazard ratio = .54, P = .15). These data suggest that p16 deletion adversely impacts the outcomes of BRAF-driven gliomas, that high proliferation index may be a better marker of progression risk than BRAF, that BRAF rearrangement and BRAF V600E might not necessarily produce comparable outcomes, and that none of these markers is stronger than tumor location in determining prognosis in pediatric low-grade gliomas.     

p73和p51基因及其在消化系统肿瘤中的作用

p73和p51基因是肿瘤抑制基因p53家族新成员.研究发现p73和p51基因的异常与许多肿瘤的发生发展有关.在各种消化道肿瘤中,p73和p51基因的异常表达平均可达到60%.通过对其深入的研究将有助于人们进一步认识肿瘤的本质,从而为肿瘤的基因治疗提供新的靶点.     

Combined deletion of p38γ and p38δ reduces skin inflammation and protects from carcinogenesis

The contribution of chronic skin inflammation to the development of squamous cell carcinoma (SCC) is poorly understood. While the mitogen-activated protein kinase p38α regulates inflammatory responses and tumour development, little is known about the role of p38γ and p38δ in these processes. Here we show that combined p38γ and p38δ (p38γ/δ) deletion blocked skin tumour development in a chemically induced carcinogenesis model. p38γ/δ deletion reduced TPA-induced epidermal hyperproliferation and inflammation; it inhibited expression of proinflammatory cytokines and chemokines in keratinocytes in vitro and in whole skin in vivo, resulting in decreased neutrophil recruitment to skin. Our data indicate that p38γ/δ in keratinocytes promote carcinogenesis by enabling formation of a proinflammatory microenvironment that fosters epidermal hyperproliferation and tumourigenesis. These findings provide genetic evidence that p38γ and p38δ have essential roles in skin tumour development, and suggest that targeting inflammation through p38γ/δ offers a therapeutic strategy for SCC treatment and prevention.     

Transcriptional dysregulation of the p73L / p63 / p51 / p40 / KET gene in human squamous cell carcinomas: expression of Delta Np73L, a novel dominant-negative isoform, and loss of expression of the potential tumour suppressor p51

We have recently identified a second p53 -related p73L gene, also referred to as p63 / p51 / p40 / KET gene, which encodes the 2 major isoforms p73L and p51 resulting from different exon usage at their amino terminal regions. Although p73L and p51 are suspected to play oncogenic and tumour suppressive roles in mammalian cells, respectively, no evidence of linkage between the expression of these isoforms and human cancers has been reported so far. In this study, we first investigated the expression profile of p51 and p73L in various human tumour cell lines and found that a novel isoform, termed DeltaNp73L, was predominantly expressed in squamous cell carcinomas. The expression profile of DeltaNp73L/p73L/p51 in primary human skin cancer specimens showed that the expression of p51 was frequently lost (62%) but was detected in all normal skin samples. In p51-expressing skin cancers, DeltaNp73L expression was associated at a high frequency (75%) though it was not detected in normal skin tissues. Transient co-transfection data indicate the possibility that DeltaNp73L can inhibit p53-, and more preferentially, p51-mediated transactivation. These data suggest that the loss of expression of p51 and/or the expression of DeltaNp73L might contribute to the pathogenesis of human squamous cell carcinomas.     

p16和p15及PCNA在子宫颈癌组织中的表达及临床病理意义

目的:研究p16、p15蛋白及增殖细胞核抗原(proliferating cell nuclear antigen,PCNA)在子宫颈癌中的表达特点,并探讨其与病理分级的关系。方法:应用免疫组织化学ElivisionTM二步法检测41例宫颈癌及30例正常宫颈组织中p16、p15及PCNA的表达情况,并结合病理分级进行分析。结果:1)p16和p15蛋白在宫颈癌组织的表达率分别为14·63%(6/41)和17·07%(7/41),明显低于在正常宫颈组织中的表达率100%(30/30)和96·67%(29/30),χ2=8·834,P=0·003;2)p16、p15蛋白阳性表达率与宫颈癌组织的病理学分级有关,p16、p15在宫颈癌Ⅰ级中的阳性表达率28·57%(4/14)、28·57%(4/14),明显高于Ⅱ级18·75%(3/16)、12·50%(2/16),χ2=6·069,P=0·014,也高于Ⅲ级9·09%(1/11)、9·09%(1/11),χ2=7·86,P=0·005;3)宫颈癌组织PCNA阳性表达率95·12%(39/41)及阳性细胞指数(47·97±8·69)%,均明显高于正常对照组的阳性表达率3·33%(1/30)及阳性细胞指数(3·56±0·53)%,χ2=10·773,P=0·001;并且与病理学分级存在相关性。结论:抑癌基因p16、p15的表达缺失在子宫颈癌中同时存在,p16、p15及PCNA检测对于研究宫颈癌的发生、发展和评估子宫颈癌恶性程度具有重要意义。