Particle irradiation suppresses metastatic potential of cancer cells

Particle radiotherapy such as proton and carbon ion has been producing promising clinical results worldwide. The purpose of this study was to compare metastatic capabilities of malignant tumor cells after irradiation with photon, proton, and carbon ion beams to clarify their ion beam-specific biological effects. We examined the biological properties of highly aggressive HT1080 human fibrosarcoma cells to assess their metastatic processes in terms of cell adhesion capability to extracellular matrix, expression of integrins, cell migration, cell invasive capability, and matrix metalloproteinase-2 activity in vitro. We then assessed the metastatic capabilities of LM8 mouse osteosarcoma irradiated with carbon ion or photon beam in the syngeneic mice. Both proton and carbon ion irradiation decreased cell migration and invasion in a dose-dependent manner and strongly inhibited matrix metalloproteinase-2 activity. On the other hand, lower X-ray irradiation promoted cell migration and invasion concomitant with up-regulation of alphaVbeta3 integrin. For cancer cells treated with carbon ion irradiation, the number of pulmonary metastasis was decreased significantly in vivo. These findings suggest that particle irradiation suppresses metastatic potential even at lower dose, whereas photon irradiation promotes cell migration and invasive capabilities at lower dose level, and provide preclinical evidence that ion beam radiotherapy may be superior to conventional photon beam therapy in possible preventive effects on metastases of irradiated malignant tumor cells.     

Expression of a novel factor in human breast cancer cells with metastatic potential.

Clinical and experimental evidence suggests that tumor cells shed into the circulation from solid cancers are ineffective in forming distant metastasis unless the cells are able to respond to growth conditions offered by the secondary organs. To identify the phenotypic properties that are specific for such growth response, we injected carcinoma cells, which had been recovered from bone marrow micrometastases in a breast cancer patient who was clinically devoid of overt metastatic disease and established in culture, into the systemic circulation of immunodeficient rats. The animals developed metastases in the central nervous system, and metastatic tumor cells were isolated with immunomagnetic beads coated with an antibody that was reactive with human cells. The segregated cell population was compared with the injected cells by means of differential display analysis, and two candidate fragments were identified as up-regulated in the fully metastatic cells. The first was an intracellular effector molecule involved in tyrosine kinase signaling, known to mediate nerve growth factor-dependent promotion of cell survival. The second was a novel gene product (termed candidate of metastasis-1), presumably encoding a DNA-binding protein of helix-turn-helix type. Constitutive expression of candidate of metastasis-1 seemed to distinguish breast cancer cells with metastatic potential from cells without metastatic potential. Hence, our experimental approach identified factors that may mediate the growth response of tumor cells upon establishment in a secondary organ and, thereby, contribute to the metastatic phenotype.     

Ezrin在高、低转移潜能乳腺癌细胞中的表达及其意义

目的:探讨埃兹蛋白(Ezrin)对人高、低转移潜能乳腺癌细胞亚系细胞增殖和侵袭能力的影响.方法:采用乳腺癌细胞系MDA-MB-435s,利用细胞穿透人工基底膜能力的差异筛选出具有高、低转移潜能的乳腺癌细胞系,采用免疫组织化学法、 RT-PCR、Western印迹法和放射免疫显像(radioimmunoimaging, RII)方法检测Ezrin蛋白在高、低转移潜能乳腺癌细胞中的表达情况.采用MTT法检测细胞增殖能力及黏附率.结果:经人工基底膜成功分离出具有高、低转移潜能的MDA-MB-435s细胞.高转移潜能MDA-MB-435s细胞中Ezrin在基因和蛋白水平的表达均显著高于低转移潜能的MDA-MB-435s细胞,差异有统计学意义(P值均< 0.001);高转移潜能MDA-MB-435s细胞的增殖能力和黏附率均高于低转移潜能的MDA-MB-435s细胞,差异有统计学意义(P值均<0.001);131I标记的抗Ezrin抗体在接种高转移潜能MDA-MB-435s细胞的裸鼠肿瘤部位的放射性浓聚要强于接种低转移潜能MDA-MB-435s细胞的裸鼠肿瘤部位,差异有统计学意义(P<0.001).结论:Ezrin在高转移潜能乳腺癌细胞中的表达水平明显高于低转移潜能细胞,2者的增殖、黏附和侵袭力都有明显差异,上述结果为Ezrin用于乳腺癌的诊断和治疗提供了理论依据.     

Characterization of the platelet-aggregating activity of cancer cells with different metastatic potential

We studied the mechanisms of platelet activation by sublines exhibiting different metastatic potential of two murine experimental tumors: sublines M4 and M9 of the benzopyrene-induced mFS6 sarcoma and sublines B77-AA6 and B77-3T3 of RSV-transformed BALB/c 3T3 fibroblasts. The neoplastic cells of both models induced platelet aggregation, secretion and prostaglandin biosynthesis. In the first model but not in the second, all these processes correlated with the in vivo malignancy of cells. Pretreatment of B77-AA6 and B77-3T3 cells with apyrase significantly decreased platelet aggregation, while pretreatment of M4 cells was ineffective. However, pretreatment with trypsin or neuraminidase was effective in reducing platelet aggregation induced by M4 cells, but not that induced by any of the others; furthermore, phospholipase A2 reduced the platelet response by all sublines. Finally, platelet-activating activity was also found in the pellets obtained following centrifugation of culture media. These results suggest that platelets are stimulated by cancer cells through different mechanisms; platelet activation by a sialo-lipo-protein complex of the cellular membrane was found to be characteristic of the model in which the platelet-aggregating activity of neoplastic cells correlated with their in vivo metastatic behavior.     

miRNA-613在乳腺癌中的表达及作用机制

  目的  探讨乳腺癌中微小RNA (microRNA,miRNA)-613表达及作用机制。  方法  收集2017年5月至2018年5月91例于南充市中心医院手术切除的乳腺癌患者的组织标本,实时荧光定量PCR检测乳腺癌组织及癌旁组织标本、乳腺癌细胞系(MDAMB-231、MDA-MB-468、MCF-7)和正常乳腺上皮细胞系HBL-100中miRNA-613的表达水平,分析其与乳腺癌患者临床病理特征的关系。TCGA数据库分析miRNA-613与乳腺癌患者预后的关系。双荧光素酶报告实验检测miRNA-613与SOX9的3'UTR区的结合情况。将miRNA-613模拟物转染至MDA-MB-231细胞,CCK-8法和Transwell侵袭及迁移实验分别检测细胞增殖活性、侵袭和迁移能力的变化,Western blot检测细胞中SOX9、β-catenin、E-Cadherin和Vimentin蛋白的表达变化。  结果  miRNA-613在乳腺癌组织中表达明显低于癌旁组织(P < 0.05),并且miRNA-613表达与TNM分期和淋巴结转移密切相关(P < 0.05),TCGA生存数据显示miRNA-613表达与乳腺癌患者的总生存率无关(P>0.05)。乳腺癌细胞系中miRNA-613的表达明显低于正常乳腺上皮细胞系(P < 0.05),并且高侵袭转移性乳腺癌细胞系MDA-MB-231、MDA-MB-468中miRNA-613的表达明显低于低侵袭转移性乳腺癌细胞系MCF-7(P < 0.05)。双荧光素酶报告实验显示miRNA-613可与SOX9的3'UTR特异性结合。上调miRNA-613的表达能抑制MDA-MB-231细胞的增殖和侵袭迁移能力(P < 0.05),同时下调SOX9、β-catenin和Vimentin蛋白的表达(P < 0.05),并上调ECadherin蛋白的表达(P < 0.05)。  结论  在乳腺癌组织和细胞中miRNA-613异常低表达,miRNA-613可能通过调控SOX9、Wnt/β-catenin信号通路抑制乳腺癌细胞的增殖、侵袭转移及上皮间质转化。      

NF-kappaB activity blockade impairs the angiogenic potential of human pancreatic cancer cells

The effect of blockade of NF-kappaB activity on human pancreatic cancer angiogenesis was determined in an orthotopic xenograft model. Highly metastatic L3.3 human pancreatic cancer cells, which expressed an elevated level of constitutive NF-kappaB activity, were transfected with a mutated IkappaBalpha (IkappaBalphaM). After implantation in the pancreas of nude mice, parental (L3.3) and control vector-transfected (L3.3-Neo) cells produced rapidly growing tumors and liver metastases, whereas IkappaBalphaM-transfected (L3.3-IkappaBalphaM) cells had decreased tumorigenicity and metastatic potential. NF-kappaB signaling blockade significantly inhibited the in vitro and in vivo expression of the major proangiogenic molecules vascular endothelial growth factor and interleukin-8 and decreased tumor vascular formation. These events were correlated with retarded tumor growth and suppression of metastasis. Collectively, these data suggest that suppression of tumorigenicity and metastasis by NF-kappaB blockade is due to impaired angiogenic potential of tumor cells.     

Cysteine cathepsin activity suppresses osteoclastogenesis of myeloid-derived suppressor cells in breast cancer

Cysteine cathepsin proteases contribute to many normal cellular functions, and their aberrant activity within various cell types can contribute to many diseases, including breast cancer. It is now well accepted that cathepsin proteases have numerous cell-specific functions within the tumor microenvironment that function to promote tumor growth and invasion, such that they may be valid targets for anti-metastatic therapeutic approaches. Using activity-based probes, we have examined the activity and expression of cysteine cathepsins in a mouse model of breast cancer metastasis to bone. In mice bearing highly metastatic tumors, we detected abundant cysteine cathepsin expression and activity in myeloid-derived suppressor cells (MDSCs). These immature immune cells have known metastasis-promoting roles, including immunosuppression and osteoclastogenesis, and we assessed the contribution of cysteine cathepsins to these functions. Blocking cysteine cathepsin activity with multiple small-molecule inhibitors resulted in enhanced differentiation of multinucleated osteoclasts. This highlights a potential role for cysteine cathepsin activity in suppressing the fusion of osteoclast precursor cells. In support of this hypothesis, we found that expression and activity of key cysteine cathepsins were downregulated during MDSC-osteoclast differentiation. Another cysteine protease, legumain, also inhibits osteoclastogenesis, in part through modulation of cathepsin L activity. Together, these data suggest that cysteine protease inhibition is associated with enhanced osteoclastogenesis, a process that has been implicated in bone metastasis.     

蛋白4.1家族在不同乳腺癌细胞株中的表达与定位

背景与目的:目前,已在多种人类肿瘤中发现蛋白4.1家族成员表达异常.本研究旨在通过检测蛋白4.1家族成员(4.1R/B/G/N)在3株转移能力不同的人乳腺癌细胞株MCF-7、T-47D和MDA-MB-231中的表达和定位,探讨蛋白4.1家族成员与乳腺癌细胞转移能力之间的关系.方法:采用Western blot检测蛋白4.1家族成员在MCF-7、T-47D和MDA-MB-231细胞中的表达;免疫荧光标记对蛋白4.1家族成员在3株细胞中的表达进行定位.结果:4.1R/B/G在3种细胞系中均有表达,在T-47D细胞中的表达量均明显高于在MCF-7细胞中的表达量(P<0.05):但在高转移性的MDA-MB-231细胞中它们的表达水平转而下降.4.1N在T-47D细胞中的表达量明显低于在MCF-7细胞中的表达量(P<0.01),而在MDA-MB-231细胞中的表达则几乎检测不到,提示4.1N表达下调或缺失与乳腺癌细胞转移能力密切相关.4.1R/B/G/N在MCF-7和T-47D细胞中均主要定位于细胞膜及胞间连接处,同时4.1B在细胞核中也有表达;而在高转移的MDA-MB-231细胞中蛋白4.1家族成员均定位于细胞质中,提示蛋白4.1家族成员亚细胞定位的改变可能是乳腺癌细胞转移过程中的重要事件.结论:4.1N表达缺失和蛋白4.1家族成员亚细胞定位的改变与乳腺癌细胞MDA-MB-231的高转移性密切相关.     

Physical activity and fitness in women with metastatic breast cancer

Purpose

This study aimed to explore differences in physical activity and fitness between women with metastatic breast cancer compared to healthy controls and factors associated with their physical activity levels.

Methods

Seventy-one women with metastatic breast cancer, aged (mean (SD)) 57.7 (9.5) and 2.9 (3.1)?years after the onset of metastatic disease, and 71 healthy controls aged 55.0 (9.4)?years participated. Of those with metastatic disease, 27 % had bone-only metastases, 35 % visceral-only metastases and 38 % bone and visceral metastases. Patient-reported outcomes and physical measures of muscle strength and aerobic fitness assessments were obtained. Participants wore a SenseWear® physical activity monitor over 7 days, and the average steps/day and the time spent in moderate-to-vigorous intensity physical activity were determined.

Results

Women with metastases were significantly (i) less aerobically fit than the control group (25.3 (5.4) vs. 31.9 (6.1)?mL???kg^?1???min^?1; P?P?P?Conclusion Women living in the community with metastatic breast cancer possessed lower aerobic fitness, reduced muscular strength and less daily physical activity compared to healthy counterparts. They also experienced poorer functioning and higher symptom burden.

Implications for Cancer Survivors

Women living with metastatic breast cancer may benefit from a physical activity programme to address their physical impairments.     

Combinatorial targeting of microRNA-26b and microRNA-101 exerts a synergistic inhibition on cyclooxygenase-2 in brain metastatic triple-negative breast cancer cells

Breast Cancer Research and Treatment - Male breast cancer is an uncommon disease, and population-based information regarding prognostic factors is limited. Most cases are hormone receptor (HR)...     

Circulating tumor cells in metastatic breast cancer

BACKGROUND.

The aim of the current study was to assess the prognostic value of baseline circulating tumor cells (CTCs) in a large cohort of patients with newly diagnosed metastatic breast cancer (MBC).

METHODS.

This retrospective study included 185 patients with newly diagnosed MBC evaluated between 2001 and 2007. CTCs were isolated and enumerated before patients started first‐line treatment using the CellSearch system. Overall survival (OS) was calculated from the date of CTC measurement, estimated by the Kaplan‐Meier product limit method, and compared between groups with the log‐rank test. Cox proportional hazards models were fitted to determine the association between CTC levels and OS after controlling for other prognostic factors.

RESULTS.

The median age of the patients at the time of MBC diagnosis was 49 years. Fifty‐six (30.3%) patients presented with de novo metastatic disease, and 129 (69.7%) presented with newly recurrent breast cancer. A total of 114 patients (61.6%) had CTC <5, and 71 (38.4%) had CTC ≥5. The median OS was 28.3 months and 15 months (P < .0001) for patients with CTC <5 and CTC ≥5, respectively. Superior survival among patients with CTC <5 was observed regardless of hormone receptor and HER‐2/neu status, site of first metastases, or whether the patient had recurrent or de novo metastatic disease. In the multivariate model, patients with CTC ≥5 had a hazards ratio of death of 3.64 (95% confidence interval, 2.11‐6.30) compared with patients with CTC <5.

CONCLUSIONS.

The results of this large retrospective study confirms that CTCs are a strong independent predictor of survival among women with either de novo or newly recurrent MBC. CTCs should be considered as a new stratification method for women with newly diagnosed MBC. Cancer 2008. © 2008 American Cancer Society.     

Clinical significance of proliferative potential of occult metastatic cells in bone marrow of patients with breast cancer

There is increasing statistical evidence that the presence of tumour cells in bone marrow detected by immunocytochemistry represents an important prognostic indicator in breast cancer, but their individual capacity to become clinical metastases is unknown. The aim of this study was to assess the proliferative capacity of these occult metastatic cells in the bone marrow of patients with various stages of breast cancer. We obtained bone marrow aspirates from 60 patients with breast cancer before treatment with chemotherapy: 17 stage II, 12 stage III and 31 stage IV. After bone marrow culture for 6-34 days (median: 17 days) under specific cell culture conditions, viable epithelial cells were detected by cytokeratin staining in 40 patients (66%). Expansion of tumour cells was poorly correlated with tumour cell detection on primary screening (P=0.06). There was a nonsignificant correlation between the number and the presence of expanded tumour cells and the UICC stage of the patients. On primary screening, tumour cell detection was positive in 56% of patients and was correlated with clinical UICC stage (P=0.01). However, with a median follow-up of 23 months, expansion of tumour cells from bone marrow was associated with decreased patient survival (P=0.04), whereas the survival difference according to detection of CK-positive cells on primary screening was not statistically significant. In conclusion, viable tumour cells can be detected in the bone marrow of breast cancer patients. Their proliferative potential could be predictive of outcome and deserves further investigation.     

OPN在乳腺癌复发转移中的意义

目的：初步研究在乳腺癌中OPN的表达及其对乳腺癌复发转移的影响。探索OPN与ER、PR、C-erbB-2等多个乳腺癌相关因子及临床病理参数的关系。方法：选取中南大学湘雅医院乳腺科1996年至2001年间手术、获随访的乳腺癌患者70例,分为5年内出现复发转移组40例（A组）和无瘤生存组30例（B组）,另选取纤维瘤组织10例（C组）及正常乳腺组织15例（D组）。应用免疫组化法检测OPN的表达情况。结果：OPN在70例乳腺癌中阳性表达率72.86%,与C组、D组OPN表达存在显著性差别（P〈0.001）。OPN与ER、PR、C-erbB-2及年龄、腋淋巴结转移、TNM分期等临床病理因素无相关性（P〉0.05）;与p53关系不确定。A、B组间OPN表达存在显著性差别。结论：OPN与乳腺癌的预后有关,高表达的患者易复发转移。     

OPN在乳腺癌复发转移中的意义

目的:初步研究在乳腺癌中OPN的表达及其对乳腺癌复发转移的影响.探索OPN与ER、PR、C-erbB-2等多个乳腺癌相关因子及临床病理参数的关系.方法:选取中南大学湘雅医院乳腺科1996年至2001年间手术、获随访的乳腺癌患者70例,分为5年内出现复发转移组40例(A组)和无瘤生存组30例(B组),另选取纤维瘤组织10例(C组)及正常乳腺组织15例(D组).应用免疫组化法检测OPN的表达情况.结果:OPN在70例乳腺癌中阳性表达率72.86%,与C组、D组OPN表达存在显著性差别(P<0.001).OPN与ER、PR、C-erbB-2及年龄、腋淋巴结转移、TNM分期等临床病理因素无相关性(P>0.05);与p53关系不确定.A、B组间OPN表达存在显著性差别.结论:OPN与乳腺癌的预后有关,高表达的患者易复发转移.