癌癥干細(xì)胞假說(shuō)

傳統(tǒng)觀點(diǎn)認(rèn)為,，癌癥是環(huán)境或內(nèi)部因素誘導(dǎo)正常細(xì)胞內(nèi)的關(guān)鍵致癌基因和腫瘤抑制基因突變導(dǎo)致的一種疾病。當(dāng)這些突變導(dǎo)致細(xì)胞向更原始,、高度增殖狀態(tài)轉(zhuǎn)化,，克隆擴(kuò)張形成白血病或?qū)嶓w腫瘤時(shí)，就會(huì)出現(xiàn)癌癥的臨床表現(xiàn)¹,。然而,，這種模式不能夠*解釋許多腫瘤和轉(zhuǎn)移瘤的長(zhǎng)發(fā)育延遲，產(chǎn)生細(xì)胞去分化和細(xì)胞永生的起始誘導(dǎo)機(jī)制,，或腫瘤本身內(nèi)的細(xì)胞功能和表型多樣性起源,。過(guò)去十年中，越來(lái)越多的證據(jù)表明，惡性腫瘤起源于組織干細(xì)胞在突變作用下的轉(zhuǎn)化,，這些突變會(huì)導(dǎo)致控制干細(xì)胞生長(zhǎng)和增殖的正常機(jī)制的調(diào)節(jié)異常^1-9,。

成體干細(xì)胞填充每個(gè)器官內(nèi)的離散區(qū)位。它們具有長(zhǎng)生命期和多能性能,，可以重新轉(zhuǎn)化成該器官內(nèi)的所有類型的細(xì)胞,。干細(xì)胞的兩個(gè)顯著特性是：

1. 在長(zhǎng)期的區(qū)位環(huán)境中保持休眠的能力，

2. 不對(duì)稱細(xì)胞分裂能力,，可分裂為一個(gè)干細(xì)胞（稱作自我更新）和一個(gè)分化的子代,。

支持CSC假說(shuō)的例證

此外，干細(xì)胞具有細(xì)胞凋亡耐受性,，具有增強(qiáng)的端粒酶和DNA修復(fù)活性,，并且具有膜結(jié)合的ABC轉(zhuǎn)運(yùn)蛋白，能夠排除異物,，從而使干細(xì)胞相對(duì)耐受劑和其他外源性毒物的損傷作用^9-11 ,。自我更新加上長(zhǎng)休眠期，使接觸損傷劑的干細(xì)胞能積聚可能隨著時(shí)間推移導(dǎo)致惡性轉(zhuǎn)化的突變³,。

癌癥干細(xì)胞鑒定

研究人員已經(jīng)從大多數(shù)白血病^2,4,13以及許多實(shí)體瘤（如腦膠質(zhì)母細(xì)胞瘤和成神經(jīng)管細(xì)胞瘤^4,5,10,14,15 ,、乳腺^3,16 、子宮頸,、結(jié)腸直腸^17,18 、胃腸道,、肝細(xì)胞,、肺、胰腺,、前列腺和皮膚癌^6,9,19,20）中分離得到少量的干細(xì)胞樣細(xì)胞,。癌癥干細(xì)胞與其對(duì)應(yīng)的正常干細(xì)胞具有相同的細(xì)胞表面標(biāo)記物（見表1），但卻表現(xiàn)出不受控制的增殖,，這可能是由于對(duì)負(fù)生長(zhǎng)調(diào)節(jié)因子或?qū)佑|抑制和間隙連接細(xì)胞間通訊（GJIC）缺失的響應(yīng)性降低所致,。^1,10

產(chǎn)品特點(diǎn)

AldeRed ALDH檢測(cè)分析

癌癥干細(xì)胞醛脫氫酶（ALDH）的表達(dá)量升高，被認(rèn)為是所有CSCs的標(biāo)志,。ALDEFLUOR™檢測(cè)試劑盒過(guò)去一直用于測(cè)量ALDH的表達(dá)水平,，并廣泛用于研究罕見的CSC群體。ALDEFLUOR檢測(cè)試劑盒的發(fā)射波長(zhǎng)位于電磁光譜的綠色區(qū)域（512nm）,。因此,，其中的試劑不能同時(shí)用于表達(dá)綠色熒光蛋白（發(fā)射綠色熒光光譜）的細(xì)胞或小鼠。AldeRed是用于標(biāo)記活A(yù)LDH陽(yáng)性細(xì)胞的ALDH紅移熒光底物,，從而釋放出綠色發(fā)射通道以幫助同步完成其他檢測(cè),。AldeRed克服了ALDEFLUOR檢測(cè)試劑盒目前的局限。

閱讀《Nature》中關(guān)于AldeRed的文章

AldeRed的特性和優(yōu)點(diǎn)：

• 紅移檢測(cè)釋放出其他實(shí)驗(yàn)所需的綠色通道

• 活體干細(xì)胞鑒定技術(shù)，能夠?qū)币姷募?xì)胞群體進(jìn)行流式分選

• 快速酶反應(yīng)檢測(cè)方案

AldeRed 588-A是一種無(wú)毒的ALDH熒光底物,，能夠自由進(jìn)入完整活細(xì)胞但其被ALDH轉(zhuǎn)化成酸產(chǎn)物后仍將滯留在細(xì)胞內(nèi),。

癌癥干細(xì)胞信號(hào)轉(zhuǎn)導(dǎo)通路

干細(xì)胞巢被充滿時(shí)，正常干細(xì)胞的自我更新將終止,。與正常干細(xì)胞不同,，癌癥干細(xì)胞和干細(xì)胞源癌祖細(xì)胞的不受控自我更新會(huì)超過(guò)其區(qū)位并滲入周圍組織¹³。Hedgehog,，Notch,，Wnt，和PTEN是控制正常和癌癥干細(xì)胞自我更新,、增殖和存活的部分途徑,。在大多數(shù)侵襲性癌癥中，都可觀察到導(dǎo)致這些途徑不同程度激活的突變,。

Hedgehog 和 Bmi1通路

Hedgehog（Hh）通路能夠調(diào)節(jié)成體干細(xì)胞的休眠和自我更新,。研究人員已經(jīng)在哺乳動(dòng)物中鑒定了三種Hh配體，即Sonic hedgehog（Shh）,、Desert hedgehog（Dhh）和Indian hedgehog（Ihh）,，其中對(duì)Shh的研究多。在沒有配體的情況下,，Hh受體PTCH1通過(guò)催化抑制跨膜蛋白Smoothened（SMO）,，從而抑制信號(hào)轉(zhuǎn)導(dǎo)。配體與PTCH1可使受體失活,，并活化SMO,，繼而誘導(dǎo)Gli轉(zhuǎn)錄因子；Gli1和Gli2是Hh信號(hào)通路的陽(yáng)性信號(hào)介導(dǎo)子,，而Gli3是負(fù)調(diào)節(jié)子^3,20,。

Bmi1的誘導(dǎo)能夠促進(jìn)許多Hh活化的效應(yīng)。Bmi1 是一個(gè)的多梳基因,，通過(guò)染色質(zhì)重塑抑制轉(zhuǎn)錄,，并能夠下調(diào)Ink-4A / ADP核糖基化因子（ARF）復(fù)合物（如p16 Ink4A 和p19 ARF）的基因表達(dá)——這些基因是細(xì)胞周期的負(fù)調(diào)節(jié)物并且參與干細(xì)胞的休眠和分化^3,4。這使得Hh通路元件PTCH1,、Gli1和Gli2表達(dá)上調(diào)^19,20,， 以及Gli1和Gli2誘導(dǎo)的生長(zhǎng)促進(jìn)基因cyclin D1、Myc和Snail表達(dá)來(lái)實(shí)現(xiàn)干細(xì)胞分化和自我更新,。

Notch-γ-分泌酶通路

Notch信號(hào)轉(zhuǎn)導(dǎo)能夠促進(jìn)正常神經(jīng)干細(xì)胞的存活和增殖,，抑制它們的分化。許多癌細(xì)胞系（包括T細(xì)胞白血病,，以及腦,、乳腺、卵巢、宮頸,、結(jié)腸直腸,、胰腺、唾液腺和肺部癌癥^3,6,9,15 ）的干細(xì)胞樣細(xì)胞中,，Notch信號(hào)轉(zhuǎn)導(dǎo)通路被高度激活,。其中，成神經(jīng)管細(xì)胞瘤和T細(xì)胞淋巴細(xì)胞白血病是Notch依賴性的惡性腫瘤¹⁵,。

Notch通路激活包括通過(guò)γ-分泌酶對(duì)Notch配體/受體復(fù)合物進(jìn)行蛋白水解切割,，從而釋放Notch胞內(nèi)結(jié)構(gòu)域片段（NICD），移位到細(xì)胞核并上調(diào)Myc,、Hes1和其他基因的表達(dá),。當(dāng)用NICD2轉(zhuǎn)染DAOY成神經(jīng)管細(xì)胞瘤細(xì)胞系使Notch通路持續(xù)激活時(shí)，轉(zhuǎn)染后的細(xì)胞比非轉(zhuǎn)染的DAOY細(xì)胞產(chǎn)生更多的異種移植腫瘤,，培養(yǎng)物中CD133 +和側(cè)群干細(xì)胞樣細(xì)胞也增加了,。相反，抑制γ-分泌酶可將側(cè)群細(xì)胞減少至總細(xì)胞計(jì)數(shù)的0.01％,，并且抑制90％的細(xì)胞形成軟瓊脂集落及在免疫受損的小鼠中形成腫瘤異種移植物的能力,。NICD2轉(zhuǎn)染可保護(hù)細(xì)胞免受γ-分泌酶抑制的影響¹⁵。因此,，在一些腫瘤類型中,，抑制Notch信號(hào)轉(zhuǎn)導(dǎo)可以消除腫瘤起始所需的細(xì)胞群。

Wnt-β-連環(huán)蛋白途徑

Wnt包含結(jié)合Frizzled（Fz）受體家族的19種胞外糖蛋白家族,，其可激活抑制β-連環(huán)蛋白的蛋白水解降解途徑,，這使得β-連環(huán)蛋白在細(xì)胞質(zhì)中積累并向細(xì)胞核轉(zhuǎn)運(yùn)。在細(xì)胞核中,，β-連環(huán)蛋白通過(guò)Tcf / Lef轉(zhuǎn)錄因子促進(jìn)基因轉(zhuǎn)錄。在Wnt未激活的情況下,，軸蛋白（Axin）和腺瘤 息肉病大腸桿菌蛋白（APC）與糖原合酶激酶3（Gsk3）形成復(fù)合物,，從而促進(jìn)細(xì)胞質(zhì)β-連環(huán)蛋白磷酸化，繼而靶向β-連環(huán)蛋白以進(jìn)行蛋白水解降解,。

Wnt通路的激活需要Fz與其共同受體（LDL受體樣蛋白5/6（Lrp5 / 6））的結(jié)合,。Wnt / Fz / Lrp5 / 6復(fù)合物的形成激活磷蛋白Dishevelled（Dvl）（Fz受體的組成成分），繼而招募Axin / Gsk3,，從而解離Axin / APC / Gsk3復(fù)合物,。Lrp5 / 6被Gsk3和酪蛋白激酶1γ（Ck1γ）。 磷酸化的Lrp5 / 6結(jié)合Axin / Gsk3形成復(fù)合體,，防止β-連環(huán)蛋白的磷酸化從而穩(wěn)定β-連環(huán)蛋白,。

圖1. 癌癥干細(xì)胞中關(guān)鍵發(fā)育信號(hào)轉(zhuǎn)導(dǎo)通路的激活。Shh、Wnt和Notch信號(hào)轉(zhuǎn)導(dǎo)途徑與維持癌癥干細(xì)胞的致瘤潛力有關(guān),。通過(guò)與Bmi1信號(hào)轉(zhuǎn)導(dǎo)介體和其他自我更新基因（如Nanog和Sox-2）的相互作用,，這些新的調(diào)節(jié)機(jī)制可以促進(jìn)或抑制自我更新，從而提供癌癥治療干預(yù)的方法,。

材料

Product # Image Description Molecular Formula Add to Cart A3230 AR-A014418 ≥98% (HPLC), solid C12H12N4O4S 價(jià)格 B1686 BIO ≥98% (HPLC) C16H10BrN3O2 價(jià)格 B9678 Monoclonal Anti-Bone Morphogenetic Protein 4 antibody produced in mouse clone 66119.11, purified immunoglobulin, lyophilized powder 價(jià)格 B7185 Anti-Breast Cancer Resistance Protein antibody produced in rabbit affinity isolated antibody, buffered aqueous solution 價(jià)格 B7684 Monoclonal Anti-Breast Cancer Resistance Protein antibody produced in mouse 250 μg/mL, clone BXP-34, tissue culture supernatant, aqueous solution 價(jià)格 B7059 Monoclonal Anti-Breast Cancer Resistance Protein antibody produced in mouse ~250 μg/mL, clone BXP-21, tissue culture supernatant, aqueous solution 價(jià)格 C2206 Anti-β-Catenin antibody produced in rabbit whole antiserum 價(jià)格 C7082 Monoclonal Anti-β-Catenin antibody produced in mouse clone 6F9, ascites fluid 價(jià)格 C7207 Monoclonal Anti-β-Catenin antibody produced in mouse clone 15B8, ascites fluid 價(jià)格 P7437 Monoclonal Anti-CD19?PE antibody produced in mouse clone SJ25-C1, purified immunoglobulin, buffered aqueous solution 價(jià)格 HPA005785 Anti-CD44 antibody produced in rabbit Prestige Antibodies®Powered by Atlas Antibodies, affinity isolated antibody, buffered aqueous glycerol solution 價(jià)格 C7923 Monoclonal Anti-CD44 antibody produced in mouse clone A3D8, purified immunoglobulin, buffered aqueous solution 價(jià)格 HPA000440 Anti-CD45 antibody produced in rabbit Prestige Antibodies®Powered by Atlas Antibodies, affinity isolated antibody, buffered aqueous glycerol solution 價(jià)格 C9819 Chondroitin sulfate A sodium salt from bovine trachea lyophilized powder, BioReagent, suitable for cell culture 價(jià)格 C3116 Anti-CXCR4 antibody produced in rabbit affinity isolated antibody, buffered aqueous solution 價(jià)格 C6598 Monoclonal Anti-CXCR4 (Fusin) antibody produced in mouse clone 44716, purified immunoglobulin, lyophilized powder 價(jià)格 C8352 Anti-CXCR4 (Fusin) (182-196) antibody produced in rabbit IgG fraction of antiserum, buffered aqueous solution 價(jià)格 C8227 Anti-CXCR4 (Fusin), N-Terminal antibody produced in rabbit IgG fraction of antiserum, buffered aqueous solution 價(jià)格 D5942 DAPT ≥98% (HPLC), solid C23H26F2N2O4 價(jià)格 D0817 (?)-Deguelin >98% (HPLC), powder C23H22O6 價(jià)格 E1270 ECM Gel from Engelbreth-Holm-Swarm murine sarcoma liquid, BioReagent, suitable for cell culture 價(jià)格 F3542 Fibronectin Fragment III1-C human recombinant, expressed in E. coli, lyophilized powder, ≥90% (SDS-PAGE) 價(jià)格 F3804 Anti-Frizzled-1 antibody produced in rabbit affinity isolated antibody, buffered aqueous solution 價(jià)格 F3179 Anti-Frizzled-3 antibody produced in rabbit affinity isolated antibody, buffered aqueous solution 價(jià)格 F3429 Anti-Frizzled-4 antibody produced in rabbit affinity isolated antibody, buffered aqueous solution 價(jià)格 F3679 Anti-Frizzled-7 antibody produced in rabbit affinity isolated antibody, buffered aqueous solution 價(jià)格 P7965 Monoclonal Anti-P-Glycoprotein (MDR) antibody produced in mouse clone F4, ascites fluid 價(jià)格 HPA003539 Anti-IL3RA antibody produced in rabbit Prestige Antibodies®Powered by Atlas Antibodies, affinity isolated antibody, buffered aqueous glycerol solution 價(jià)格 J4127 Anti-Jagged 1 antibody produced in goat affinity isolated antibody, lyophilized powder 價(jià)格 J4145 Jervine ≥98% (HPLC), powder C27H39NO3 價(jià)格 L1790 L-685,458 >96% (HPLC), solid C39H52O6N4 價(jià)格 L4020 Monoclonal Anti-LEF-1 (β-Catenin binding domain) antibody produced in mouse clone REMB1, ~1 mg/mL, purified immunoglobulin, buffered aqueous solution 價(jià)格 T2949 Anti-mTOR antibody produced in rabbit 1.0-1.5 mg/mL, affinity isolated antibody, buffered aqueous solution 價(jià)格 N8523 Monoclonal Anti-NF-κB antibody produced in mouse clone NF-12, ascites fluid 價(jià)格 N6786 Monoclonal Anti-Notch1 antibody produced in mouse clone mN1A, purified immunoglobulin, buffered aqueous solution 價(jià)格 N9286 Notch-1/Fc Chimera from rat recombinant, expressed in NSO cells, ≥90% (SDS-PAGE), lyophilized powder, from rat 價(jià)格 N9161 Notch-2/Fc Chimera from rat recombinant, expressed in NSO cells, ≥90% (SDS-PAGE), lyophilized powder 價(jià)格 P4235 Anti-p53 antibody produced in sheep fractionated antiserum, buffered aqueous solution 價(jià)格 P5813 Monoclonal Anti-p53 antibody produced in mouse clone BP53-12, ascites fluid 價(jià)格 P8999 Monoclonal Anti-p53 antibody produced in mouse clone DO-7, purified from hybridoma cell culture 價(jià)格 P7874 Monoclonal Anti-p53 antibody produced in mouse ~2 mg/mL, clone DO-2, purified immunoglobulin, buffered aqueous solution 價(jià)格 P6874 Monoclonal Anti-p53 antibody produced in mouse clone DO-1, purified from hybridoma cell culture 價(jià)格 P0667 Parthenolide ≥98% (HPLC) C15H20O3 價(jià)格 P4707 Poly-L-lysine solution mol wt 70,000-150,000, 0.01%, sterile-filtered, BioReagent, suitable for cell culture 價(jià)格 P4832 Poly-L-lysine solution mol wt 150,000-300,000, 0.01%, sterile-filtered, BioReagent, suitable for cell culture 價(jià)格 P7482 Anti-PTEN antibody produced in rabbit IgG fraction of antiserum, buffered aqueous solution 價(jià)格 P3487 Monoclonal Anti-PTEN antibody produced in mouse ~1 mg/mL, purified immunoglobulin, clone PTN-18, buffered aqueous solution 價(jià)格 R1276 Reversin 121 ≥97% (HPLC), powder C34H47N3O9 價(jià)格 R1401 Reversin 205 ≥98% (HPLC), film C41H58N4O12 價(jià)格 S4572 SANT-1 ≥98% (HPLC), powder C23H27N5 價(jià)格 S2188 γ-Secretase inhibitor ≥90% (TLC), powder C33H57F2N5O9 價(jià)格 S9819 Anti-Smoothened Drosophila Homolog antibody produced in rabbit affinity isolated antibody 價(jià)格 S0191 Sonic Hedgehog Peptide from mouse ≥97% (SDS-PAGE), recombinant, expressed in E. coli, Fused to a histidine tag at the C-terminus, lyophilized powder 價(jià)格 S8321 Monoclonal Anti-Sonic Hedgehog (Shh) 小鼠抗 clone SH154, purified from hybridoma cell culture 價(jià)格 S4944 Monoclonal Anti-Sonic Hedgehog (N-terminal) antibody produced in rat clone 171018, purified immunoglobulin, lyophilized powder 價(jià)格 S5174 SPARC from murine parietal yolk sac (PYS-2) cells ~80% (SDS-PAGE), lyophilized powder 價(jià)格 HPA001671 Anti-STAT3 antibody produced in rabbit Prestige Antibodies®Powered by Atlas Antibodies, affinity isolated antibody, buffered aqueous glycerol solution 價(jià)格 S5933 Anti-STAT3 antibody produced in rabbit IgG fraction of antiserum, buffered aqueous solution 價(jià)格 V1014 Anti-Vascular Endothelial Growth Factor Receptor 2 antibody produced in goat affinity isolated antibody, lyophilized powder 價(jià)格 V8379 Vitronectin 來(lái)源于人類血漿 lyophilized powder, BioReagent, suitable for cell culture 價(jià)格 W2266 Anti-Wnt-4 antibody produced in goat affinity isolated antibody, lyophilized powder 價(jià)格 P7280 多聚-D-賴氨酸 氫溴酸鹽 average mol wt 30,000-70,000, lyophilized powder, γ-irradiated, BioReagent, suitable for cell culture 價(jià)格 P6407 多聚-D-賴氨酸 氫溴酸鹽 mol wt 70,000-150,000, lyophilized powder, γ-irradiated, BioReagent, suitable for cell culture 價(jià)格 L2020 層粘蛋白 來(lái)源于 Engelbreth-Holm-Swarm 小鼠肉瘤基底膜 1-2 mg/mL in Tris buffered NaCl, 0.2 μm filtered, BioReagent, suitable for cell culture 價(jià)格 L6274 層粘蛋白 來(lái)源于人類胎盤 liquid, BioReagent, suitable for cell culture 價(jià)格 C4116 環(huán)巴胺 水合物 ≥98% (HPLC) C27H41NO2 · xH2O 價(jià)格 F2006 Fibronectin human plasma 纖連蛋白 溶液 來(lái)源于人類成纖維細(xì)胞 lyophilized powder, BioReagent, suitable for cell culture 價(jià)格 F0895 Fibronectin human plasma 纖連蛋白 溶液 來(lái)源于人類成纖維細(xì)胞 liquid, 0.1% (Solution), BioReagent, suitable for cell culture 價(jià)格 F0635 Fibronectin rat plasma 纖連蛋白 溶液 來(lái)源于人類成纖維細(xì)胞 powder, BioReagent, suitable for cell culture 價(jià)格 P9155 聚-L-賴氨酸 氫溴酸鹽 mol wt 30,000-70,000, lyophilized powder, γ-irradiated, BioXtra, suitable for cell culture 價(jià)格 P6282 聚-L-賴氨酸 氫溴酸鹽 mol wt 70,000-150,000, lyophilized powder, γ-irradiated, BioXtra, suitable for cell culture 價(jià)格 P5899 聚-L-賴氨酸 氫溴酸鹽 mol wt ≥300,000, lyophilized powder, γ-irradiated, BioXtra, suitable for cell culture 價(jià)格 P4957 聚-L-鳥氨酸 溶液 mol wt 30,000-70,000, 0.01%, sterile-filtered, BioReagent, suitable for cell culture 價(jià)格 C5533 膠原 來(lái)源于人類胎盤 Bornstein and Traub Type IV, powder, BioReagent, suitable for cell culture 價(jià)格 C7661 膠原 來(lái)源于大鼠尾 Bornstein and Traub Type I, powder, BioReagent, suitable for cell culture 價(jià)格

參考文獻(xiàn)

1. Trosko, J.E., et al., Ignored hallmarks of carcinogenesis: stem cells and cell-cell communication. Ann. NY Acad. Sci., 1028, 192-201 (2004).

2. Dick, J.E., Acute myeloid leukemia stem cells. Ann. NY Acad. Sci., 1044, 1-5 (2005).

3. Liu, S., et al., Hedgehog signaling and Bmi-1 regulate self-renewal of normal and malignant human mammary stem cells. Cancer Res., 66, 6063-6071 (2006).

4. Massard, C., et al., Tumor stem cell-targeted treatment: elimination or differentiation. Ann. Oncol., 17, 1620-1624 (2006).

5. Meletis, K., et al., p53 suppresses the self-renewal of adult neural stem cells. Development, 133, 363-369 (2006).

6. Mimeault, M., and Batra, S.K., Concise review: recent advances on the significance of stem cells in tissue regeneration and cancer therapies. Stem Cells, 24, 2319-2345 (2006).

7. Shen, R., et al., Precancerous stem cells can serve as tumor vasculogenic progenitors. PLOS One, 3, e1652 (2008).

8. Vermeulen, L., et al., Cancer stem cells - old concepts, new insights. Cell. Death Differ., e-pub Feb 15. 2008.

9. Wicha, M.S., et al., Cancer stem cells: an old idea - a paradigm shift. Cancer Res., 66, 1883-1890 (2006).

10. Sakariassen, P.O., et al., Cancer stem cells as mediators of treatment resistance in brain tumors: status and controversies. Neoplasia, 9, 882-892 (2007).

11. Styczynski, J., and Drewa, T., Leukemic stem cells: from metabolic pathways and signaling to a new concept of drug resistance targeting. Acta Biochim. Pol., 54, 717-726 (2007).

12. Bailey, P., and Cushing, H., A Classification of the Tumors of the Glioma Group on a Histogenetic Basis with a Correlated Study of Prognosis. Philadelphia: J.P. Lippincott, (1926).

13. Strewler, G.J., The stem cell niche and bone metastasis. BoneKEy-Osteovision, 3, 19-29 (2006).

14. Singh, S.K., et al. Identification of a cancer stem cell in human brain tumors. Cancer Res., 63, 5821-5828 (2003).

15. Fan, X., et al., Notch pathway inhibition depletes stem-like cells and blocks engraftment in embryonal brain tumors. Cancer Res., 66, 7445-7452 (2006).

16. Benhaj, K., et al., Redundant expression of canonical Wnt ligands in human breast cancer cell lines. Oncol. Rep., 15, 701-707 (2006).

17. Fodde, R., and Brabletz, T., Wnt/β-catenin signaling in cancer stemness and malignant behavior. Curr. Opin. Cell Biol., 19, 150-158 (2007).

18. Zhou, J., et al., Activation of the PTEN/mTOR/STAT3 pathway in breast cancer stemlike cells is required for viability and maintenance. Proc. Natl. Acad. Sci. USA, 104, 16158-16163 (2007).

19. Mimeault, M., and Batra, S.K., Interplay of distinct growth factors during epithelialmesenchymal transition of cancer progenitor cells and molecular targeting as novel cancer therapies. Ann. Oncol., 18, 1605-1619 (2007).

20. Peacock, C.D., et al., Hedgehog signaling maintains a tumor stem cell compartment in multiple myeloma. Proc. Natl. Acad. Sci. USA, 104, 4048-4053 (2007).

21. Bao, S., et al., Stem cell-like glioma cells promote tumor angiogenesis through vascular endothelial growth factor. Cancer Res., 66, 7843-7848 (2006).

22. O’Neil, J., et al., FBW7 mutations in leukemic cells mediate NOTCH pathway activation and resistance to γ-secretase inhibitors. J. Exp. Med., 204, 1813-1824 (2007).

23. He, X., and Axelrod, J.D., A WNTer wonderland in Snowbird. Development, 133, 2597-2603 (2006).

24. Zeng, X., et al., Initiation of Wnt signaling: control of Wnt coreceptor Lrp6 phosphorylation/activation via frizzled, disheveled and axin functions. Development, 135, 367-375 (2008).

25. Groszer, M., et al., PTEN negatively regulates neural stem cell self-renewal by modulating G0-G1 cell cycle entry. Proc. Natl. Acad. Sci. USA,103, 111-116 (2006).

26. Hede, K., PTEN takes center stage in cancer stem cell research, works as tumor suppressor. J. Nat. Cancer Inst., 98, 808-809 (2006).

27. A red-shifted fluorescent substrate for aldehyde dehydrogenase. Martin G. Pomper et al. Nature Communications 5, Article number: 3662 23 April 2014

back to top