Clinical drug-resistant nodular sclerosing Hodgkin's lymphoma is associated with decreased bcl-2 expression in the surrounding lymphocytes and with increased bcl-2 expression in the Reed-Sternberg cells

Identification of patients with Hodgkin's lymphoma who are primary refractory to chemotherapy will have great impact on treatment planning. Several studies have indicated that up-regulation of the bcl-2 proto-oncogene expression in non-Hodgkin's lymphoma can cause resistance to chemotherapeutic drugs. For this reason we investigated the relationship between expression of bcl-2, the pro-apoptotic protein Bax and MIB-1 with clinical drug-resistance in Hodgkin's lymphoma. METHODS AND RESULTS: Seven patients with nodular sclerosis Hodgkin's lymphoma under 40 years of age, who failed to achieve complete remission upon primary chemotherapy and 10 matched patients who did achieve complete response were selected from the Eindhoven Cancer Registry. Tissue sections from both groups of patients were stained for bcl-2, Bax and MIB-1. In the non-responding patients Reed-Sternberg cells expressed bcl-2 more frequently using a cut-off point of <25% to indicate negative cells (P = 0.04), whereas no differences were observed in the expression of Bax and MIB-1. In non-responding patients the lymphocytes surrounding Reed-Sternberg cells expressed bcl-2 less frequently (P = 0.002), using a cut-off point of < 25%, whereas no difference was observed in the expression of Bax and MIB-1. CONCLUSION: A high percentage of Reed-Sternberg cells expressing bcl-2 protein and a low expression of bcl-2 proteifi in the surrounding lymphocytes is associated with treatment-failure, and subsequent poor survival in young patients with nodular sclerosing Hodgkin's lymphoma. These results need further validation in larger studies.     

Membranous expression of Her3 is associated with a decreased survival in head and neck squamous cell carcinoma

Background

Head and neck squamous cell carcinoma (HNSCC) still remains a lethal malignancy benefiting from the identification of the new target for early detection and/or development of new therapeutic regimens based on a better understanding of the biological mechanism for treatment. The overexpression of Her2 and Her3 receptors have been identified in various solid tumors, but its prognostic relevance in HNSCC remains controversial.

Methods

Three hundred eighty-seven primary HNSCCs, 20 matching metasis and 17 recurrent HNSCCs were arrayed into tissue microarrays. The relationships between Her2 and Her3 protein expression and clinicopathological parameters/survival of HNSCC patients were analyzed with immunohistochemistry.

Results

Her3 is detected as either a cytoplasmic or a membranous dominant expression pattern whereas Her2 expression showed uniform membranous form. In primary tumor tissues, high membranous Her2 expression level was found in 104 (26.9%) cases while positive membranous and cytoplasmic Her3 expression was observed in 34 (8.8%) and 300 (77.5%) samples, respectively. Membranous Her2 expression was significantly associated with histological grade (P = 0.021), as grade 2 tumors showed the highest positive expression. Membranous Her3 over-expression was significantly prevalent in metastatic tissues compared to primary tumors (P = 0.003). Survival analysis indicates that membranous Her3 expression is significantly associated with worse overall survival (P = 0.027) and is an independent prognostic factor in multivariate analysis (hazard ratio, 1.51; 95% confidence interval, 1.01-2.23; P = 0.040).

Conclusions

These results suggest that membranous Her3 expression is strongly associated with poor prognosis of patients with HNSCC and is a potential candidate molecule for targeted therapy.

     

bcl—2／bax对不同乳腺癌细胞凋亡的调节作用

目的：了解bcl-2/bax在乳腺癌细胞的p53依赖性凋亡和p53非依赖性凋亡中的作用。方法：用原位杂交的方法检测化疗药物VM-26诱导入乳腺癌细胞株MCF-7和MDA-MB-435S凋亡前后bcl-2和bax的mRNA表达情况。结果：与MDA-MB-435S细胞相比,MCF-7细胞的bcl-2 mRNA水平较高。两株细胞均能在VM-26的作用下发生凋亡。药物诱导后,MCF-7细胞的bcl-2 mRNA表达下降,bax mRNA表达增加;MDA-MB-435S细胞bax mRNA表达增加,bcl-2、mRNA无明显变化。结论：wt p53可在转录水平调节bcl-2/bax的表达,从而介导凋亡作用;bax在p53非依赖性凋亡中也发挥一定作用;bcl-2的高表达可能与肿瘤耐药性有关。     

Aging is associated with increased proliferation and decreased apoptosis in the colonic mucosa

Although the incidence of colon cancer increases with advancing age, reasons for this increase are not fully understood. Earlier studies have demonstrated that in Fischer-344 rats, aging is associated with increased crypt cell production in the colon, an event considered to be central to the initiation of carcinogenesis. Apoptosis also plays a critical role in the development and progression of colon cancer. Therefore, we have examined the age-related changes in proliferation and apoptosis in the colonic mucosa of 4-5, 12-14, and 22-24 month-old Fischer-344 rats. We have observed that proliferative activity in the colon, as assessed by proliferating cell nuclear antigen immunoreactivity, is higher (50-80%) in 12-14 and 22-24 month-old rats than in their 4-6 month-old counterparts. In contrast, the number of apoptotic cells, (as determined by TdT-mediated dUTP nick-end labeling assay) in the colonic mucosa of 12-14 and 22-24 month-old rats are considerably lower (50-60%) than in 4-6 month-old animals. These changes are accompanied by a concomitant reduction (75%) in pro-apoptotic Bak and stimulation (200%) of anti-apoptotic Bcl-xL levels. Since activation of caspases is associated with initiation and maintenance of apoptosis, we also analyzed the levels of pro and active forms of caspase-3, 8 and 9. The levels of active forms of caspase-3, 8 and 9 are found to be considerably (60-80%) lower in the colonic mucosa of 22-24 month-old rats, compared to their younger counterparts. This is accompanied by decreased cleavage of poly(ADP-ribose) polymerase, a substrate for caspases. In conclusion, our data show that aging enhances proliferation, but attenuates apoptosis in the colonic mucosa. These changes may partly be responsible for the age-related rise in colorectal cancer.     

鼻咽癌组织中bcl-2、bax和p53的表达及其与瘤细胞凋亡的关系

目的：了解鼻咽癌组织中瘤细胞ｂｃｌ２、ｂａｘ和ｐ５３的表达及其与瘤细胞凋亡指数（ａｐｏｐｔｏｓｉｓｉｎｄｅｘ,ＡＩ）的关系。方法：对３８例未经治疗的鼻咽癌组织,应用免疫组化ＬＳＡＢ法检测瘤细胞ｂｃｌ２、ｂａｘ和ｐ５３的表达;末端标记细胞死亡检测法（ＴＵＮＥＬ）计算癌细胞的凋亡指数。结果：（１）３７例（９７４％）中有９０％左右的瘤细胞呈ｂｃｌ２过表达;（２）３８例（１００％）中有７０％左右的瘤细胞过表达ｂａｘ;（３）２９例（７６３％）呈ｐ５３过表达;（４）３８例活检组织的平均ＡＩ为２６０２±２６４２／ＨＰＦ;（５）ＡＩ与ｂｃｌ２、ｂａｘ和ｐ５３的表达无相关性。结论：（１）本组大多数鼻咽癌组织的绝大部分瘤细胞均呈ｂｃｌ２和ｂａｘ高表达;（２）由于ｂｃｌ２和ｂａｘ的表达已在高水平达到相对平衡,因此在大多数人体鼻咽癌中它们可能并不起到介导瘤细胞凋亡的主导作用;（３）鼻咽癌组织中过表达的ｐ５３蛋白可能已失去了调节ｂｃｌ２和ｂａｘ的表达进而影响细胞凋亡的功能。     

Abnormal expression of bcl-2 and bax in rat tongue mucosa during the development of squamous cell carcinoma induced by 4-nitroquinoline 1-oxide

4-Nitroquinoline 1-oxide (4NQO)-induced rat tongue carcinogenesis is a useful model for studying oral squamous cell carcinoma. The aim of this study was to investigate the expression of bcl-2 and bax during tongue carcinogenesis induced by 4NQO. Male Wistar rats were distributed into three groups of 10 animals each and treated with 50 ppm 4NQO solution through their drinking water for 4, 12 or 20 weeks. Ten animals were used as negative control. Although no histological changes were induced in the epithelium after 4 weeks of carcinogen exposure, bcl-2 and bax were over-expressed (P < 0.01) in all layers of the 'normal' epithelium. The expression levels were the same in all layers of epithelium for both the antibodies used (bcl-2 or bax). In dysplastic lesions at 12 weeks following carcinogen administration, the levels of bcl-2 and bax expression did not increase when compared to negative control with the immunoreactivity for bcl-2 being restricted to the superficial layer of epithelium. In well-differentiated squamous cell carcinoma induced after 20 weeks of treatment with 4NQO, bcl-2 was expressed in some cells of tumour islands. On the other hand, immunostaining for bax was widely observed at the tumour nests. The labelling index for bcl-2 and bax showed an increase (P < 0.05) after only 4 weeks of 4NQO administration. In conclusion, our results suggest that abnormalities in the apoptosis pathways are associated with the development of persistent clones of mutated-epithelial cells in the oral mucosa. Bcl-2 and bax expression appears to be associated with a risk factor in the progression of oral cancer.     

Time dependent bladder apoptosis induced by acute bladder outlet obstruction and subsequent emptying is associated with decreased MnSOD expression and Bcl-2/Bax ratio

Ischemia/reperfusion (I/R) injury-induced oxidative stress plays an important role in the functional impairment of the bladder following acute bladder outlet obstruction (BOO) via induction of apoptosis. The purpose of this study was to investigate the time course of the bladder apoptosis, and apoptosis related molecular changes in the early stage of acute BOO. Twelve-week-old male Sprague Dawley rats were divided into control, acute BOO only (I), and acute BOO plus subsequent emptying (I/R) for 30, 60, 120 min, 3 days and 2 weeks. We examined the extent of bladder apoptosis, expression of Mn-superoxide dismutase (Mn-SOD), Bcl-2, Bax, caspase 3 and poly (ADP-ribose) (PAR) in the bladder. Bladder apoptosis was significantly increased in the I/R group at 30, 60, and 120 min following bladder emptying. BOO plus subsequent emptying for 30, 60, 120 min showed significant decrease in MnSOD and Bcl-2 expression, and significant increase in caspase 3, Bax expression, and amounts of PAR. These results indicate that bladder apoptosis, induced by acute BOO and subsequent emptying, is associated with decreased MnSOD expression, increased PARP activity and imbalance in apoptosis pathways.     

大鼠淋巴滞留性脑病bcl-2、bax表达和细胞凋亡的动态变化

目的：研究大鼠淋巴滞留性脑病模型中大脑皮层bcl-2、bax基因表达和细胞凋亡的动态变化。 方法： 用阻断颈部淋巴引流的方法复制大鼠淋巴滞留性脑病模型，术后1、2、3、5、7和14 d处死动物，HE染色观察脑组织结构变化，TUNEL荧光标记检测原位细胞凋亡，RT-PCR检测大脑皮层凋亡相关基因bcl-2和bax的表达。 结果： 显微镜下见脑组织有水肿的结构变化, 第5 d最明显。大脑皮层TUNEL阳性细胞数和bax表达从术后2 d开始增多，5 d达最高峰，14 d降至对照组水平。bcl-2表达于术后1 d开始增高，5 d达最高值，第7 d下降至对照组水平。bax表达增高的程度大于bcl-2。 结论： 阻断颈部淋巴引流可导致淋巴滞留性脑病，大脑皮层神经细胞死亡以凋亡为主并与bcl-2和bax的表达增加有关。     

Comparative analysis of the expression of proliferating cell nuclear antigen, p53, bax, and bcl-2 in oral lichen planus and oral squamous cell carcinoma

Several epidemiologic studies have shown the malignant transformation potential of oral lichen planus; however, this potential is subject of much controversy. To evaluate the expression of proteins related to the cell proliferation and apoptosis processes in oral lichen planus, we compared oral lichen planus with oral squamous cell carcinoma. Twenty-four cases of each lesion were submitted according to streptavidin-biotin technique to evaluate the immunohistochemical expression of proliferating cell nuclear antigen, p53, bax, and bcl-2 proteins. χ² test showed no statistically significant differences between the expression of p53, bax, and bcl-2 in oral lichen planus and oral squamous cell carcinoma (P > .05). However, the expression of proliferating cell nuclear antigen was significantly lower in oral lichen planus than in oral squamous cell carcinoma (P < .05). No statistically significant differences between the expression of p53, bax, and bcl-2 in oral lichen planus and oral squamous cell carcinoma were observed, which may be an evidence of the potential of malignant transformation of oral lichen planus.     

HLA-DR expression is associated with excellent prognosis in squamous cell carcinoma of the larynx

We studied class I I antigen expression and tumor-infiltrating leukocytes (TIL) in tissue sections of 69 squamous cell carcinomas of the larynx and 24 lymph node metastases in the neck. HLA-DR expression was found only in eight well-differentiated, highly keratinizing squamous cell carcinomas comprising seven of the verrucous variety and one ventriculosaccular tumor. None of the metastases was positive for DR antigen. Neither primary tumors nor autologous metastases stained for DP or DQ antigens. DR-positive tumors shared a peculiar pattern of TIL composed mainly of T cells, most of which belonged to the cytotoxic/suppressor subset, and B cells. These neoplasms had in common a slow rate of growth, and are considered low-grade carcinomas in the literature. We conclude from our study that HLA-DR expression seems to characterize tumors with a prominent infiltrate and an excellent prognosis.     

二苯乙烯苷对同型半胱氨酸诱导血管内皮细胞凋亡及bcl-2、bax、caspase-3表达的影响

 目的：研究何首乌二苯乙烯苷（TSG）对同型半胱氨酸（Hcy）诱导人脐静脉内皮细胞（HUVECs）凋亡及bcl-2、bax和caspase-3 mRNA表达的影响。方法：建立Hcy （3 mmol/L）所致培养HUVECs核损伤模型,TSG（1和10 μmol/L）提前2 h预孵育,然后再以Hcy处理,作为TSG保护组。用Hoechst 33342核染色法观察HUVECs细胞核损伤状态,以流式细胞术检测细胞凋亡情况,用实时荧光定量RT-PCR法检bcl-2、bax和caspase-3 mRNA的表达。结果：经3 mmol/L Hcy处理后,与正常培养的细胞相比,HUVECs核损伤加重,凋亡细胞比例升高,bcl-2表达降低（P＜0.01）,bax和caspase-3表达增加（P＜0.01）。TSG 1 μmol/L和10 μmol/L预孵育后再经3 mmol/L Hcy处理,与单经3 mmol/L Hcy损伤模型组相比,HUVECs细胞核损伤降低,凋亡率下降,bcl-2的表达增加（P＜0.05）,bax和caspase-3表达降低（P＜0.05）。结论：TSG具有降低Hcy所致HUVECs的细胞损伤和抑制凋亡的作用,其机制可能与影响bcl-2、bax和caspase-3的表达有关。     

The extent of apoptosis is inversely associated with bcl-2 expression in premalignant and malignant breast lesions

 

Aims:

In this study we investigated the extent of apoptosis in benign, premalignant and malignant breast lesions and its association with the immunohistochemical expression of bcl-2 oncoprotein.  

Methods and results:

In order to detect apoptotic cells and bodies in tissue sections, the 3'-end DNA labelling method was used. Immunohistochemical staining was performed by using the avidin–biotin–peroxidase complex technique. A monoclonal antibody agains bcl-2 oncoprotein was used and the specificity of the antibody was confirmed by immunoblot analysis. According to the results the extent of apoptosis, as determined by the apoptotic index, was lowest in benign ductal hyperplasias and sclerosing adenoses (0.15% and 0.07%, respectively). It was moderately elevated in atypical hyperplasias and in-situ carcinomas (0.20% and 0.40%, respectively) and highest in invasive carcinomas (0.76%). In ductal invasive carcinomas, grade I lesions showed a lower apoptotic index (0.52%) than grade II (0.72%) and grade III (1.17%) carcinomas. The apoptotic index was not significantly lower in lobular (0.82%) than in ductal invasive carcinomas (0.85%). bcl-2 immunohistochemistry was inversely related to the apoptotic index. In all cases studied the inverse association was very strong ( P  = 0.0004) but it was also present when only carcinomas were analysed ( P  = 0.01). In benign and atypical hyperplasias, bcl-2 positivity was observed in all cases, but such cases were less frequent in in-situ lesions and in invasive carcinomas.  

Conclusions:

The results show that there is an inverse relationship between the extent of apoptosis and bcl-2 expression in breast lesions suggesting that its expression affects the regulation of apoptosis in them.     

大肠腺瘤及癌中细胞凋亡和bcl—2,bax基因的表达

探讨细胞凋亡及其调控基因ｂｃｌ－２和ｂａｘ与大肠癌发生发展之间的关系。方法：采用Ｆｅｕｌｇｅｎ染色，ＴｄＴ酶介导的生物素化ｄＵＴＰ缺口末端标记技术和免疫组织Ｓ－Ｐ法，分别检测大肠正常粘膜、腺瘤、癌及癌旁非腺瘤性不典型增生中细胞凋亡率和ｂｃｌ－２、ｂａｘ基因的表达。     

前列腺病变组织中细胞凋亡与bcl-2、bax、PCNA表达

目的　研究前列腺良、恶性病变组织中细胞增殖与凋亡及其与相关蛋白表达意义。方法　采用原位细胞凋亡标记技术 (TUNEL)及免疫组织化学ABC法对 36例前列腺癌 (PCa)、2 0例前列腺增生 (BPH)和 11例正常前列腺 (NP)组织石蜡切片bcl 2、bax、PCNA蛋白及细胞凋亡检测。结果　前列腺癌细胞凋亡指数 (AI)高于BPH和NP(P <0 0 1) ,bcl 2蛋白阳性表达者AI低于阴性者 (P <0 0 1) ,bax蛋白阳性表达者AI高于阴性者 (P <0 0 5 ) ;前列腺癌和BPH的bcl 2和PCNA蛋白阳性表达率高于NP(P <0 0 5 ) ,并随着肿瘤分级增高而增高 ;NP、BPH和前列腺癌的bax蛋白阳性表达率差异无显著性。前列腺癌细胞增殖指数 (PI)明显高于BPH(P <0 0 1) ,BPH细胞PI较NP明显增高 ,但细胞AI却显著下降。结论　细胞增殖与细胞凋亡的增加在PCa的发生和发展中起到了重要作用。在BPH的形成过程中前列腺组织细胞增殖增加而细胞凋亡减少 ,其中bcl 2和bax在细胞凋亡调节中起重要作用。     

Nuclear expression of phosphorylated EGFR is associated with poor prognosis of patients with esophageal squamous cell carcinoma.

OBJECTIVES: Although it has been reported that epidermal growth factor receptor (EGFR) is able to translocate from the plasma membrane to the nucleus, the pathophysiological role of this translocation in tumorigenicity is still unclear. In the present study, to elucidate the pathophysiological significance of EGFR translocation, we investigated the expression not only of conventional EGFR but also its phosphorylated form (pEGFR), focusing on its cellular localization in esophageal cancer tissues. METHODS: Fifty-two specimens of esophageal squamous cell carcinoma (SCC) obtained by surgery were examined immunohistochemically for their EGFR and pEGFR immunostaining patterns. The relationships between clinicopathological parameters and EGFR or pEGFR immunostaining patterns were then analyzed. RESULTS: In 37 (71.2%) of the 52 esophageal SCCs, EGFR immunoreactivity was clearly localized at the plasma membrane of the cancer cells, whereas pEGFR immunoreactivity was clearly localized in the nucleus in 19 (36.5%) cases. Nuclear expression of pEGFR significantly correlated with TNM stage and lymph node metastasis, and moreover was associated with a poor outcome of esophageal SCC. CONCLUSIONS: Nuclear translocalization of pEGFR is associated with an increase in the malignant potential of esophageal SCC and may affect prognosis in patients with esophageal SCC.     

大鼠脑局灶性缺血再灌注后的细胞凋亡及bcl-2、bax蛋白表达的改变和银杏叶提取物干预的研究

目的探讨大鼠大脑中动脉重度栓塞再灌注动物的脑细胞凋亡及其相关调控基因bcl鄄2、bax阳性蛋白质表达的变化和银杏叶提取物(EGB)的治疗作用。方法采用插线法制作大鼠大脑中动脉栓塞后再灌注模型。将大鼠随机分为对照组、栓塞3h组、栓塞3h再灌注24h组、栓塞3h再灌注48h组、栓塞3hEGB干预、再灌注24hEGB干预组、再灌注48hEGB干预组。观察脑缺血/再灌注不同时点大鼠脑细胞凋亡(TUNEL法)、凋亡相关基因bcl鄄2、bax(S鄄P免疫组化法)的阳性表达和EGB对其治疗作用。EGB干预方法:术后2min腹腔注射,8h/次。结果大鼠大脑中动脉栓塞3h、栓塞3h/再灌注24、48h时,bcl鄄2、bax表达增强,细胞凋亡逐步加重,损伤加重。EGB干预后,bcl鄄2表达增强、bax表达减弱,细胞凋亡明显减少。结论细胞凋亡与bcl鄄2/bax有关,银杏叶提取物(EGB761)可以明显抑制大鼠脑组织缺血/再灌注后细胞凋亡的发生。