癌癥干細胞假說

傳統觀點認為，癌癥是環境或內部因素誘導正常細胞內的關鍵致癌基因和腫瘤抑制基因突變導致的一種疾病。當這些突變導致細胞向更原始、高度增殖狀態轉化，克隆擴張形成白血病或實體腫瘤時，就會出現癌癥的臨床表現¹。然而，這種模式不能夠*解釋許多腫瘤和轉移瘤的長發育延遲，產生細胞去分化和細胞永生的起始誘導機制，或腫瘤本身內的細胞功能和表型多樣性起源。過去十年中，越來越多的證據表明，惡性腫瘤起源于組織干細胞在突變作用下的轉化，這些突變會導致控制干細胞生長和增殖的正常機制的調節異常^1-9。

成體干細胞填充每個器官內的離散區位。它們具有長生命期和多能性能，可以重新轉化成該器官內的所有類型的細胞。干細胞的兩個顯著特性是：

1. 在長期的區位環境中保持休眠的能力，

2. 不對稱細胞分裂能力，可分裂為一個干細胞（稱作自我更新）和一個分化的子代。

支持CSC假說的例證

此外，干細胞具有細胞凋亡耐受性，具有增強的端粒酶和DNA修復活性，并且具有膜結合的ABC轉運蛋白，能夠排除異物，從而使干細胞相對耐受劑和其他外源性毒物的損傷作用^9-11 。自我更新加上長休眠期，使接觸損傷劑的干細胞能積聚可能隨著時間推移導致惡性轉化的突變³。

癌癥干細胞鑒定

研究人員已經從大多數白血病^2,4,13以及許多實體瘤（如腦膠質母細胞瘤和成神經管細胞瘤^4,5,10,14,15 、乳腺^3,16 、子宮頸、結腸直腸^17,18 、胃腸道、肝細胞、肺、胰腺、前列腺和皮膚癌^6,9,19,20）中分離得到少量的干細胞樣細胞。癌癥干細胞與其對應的正常干細胞具有相同的細胞表面標記物（見表1），但卻表現出不受控制的增殖，這可能是由于對負生長調節因子或對接觸抑制和間隙連接細胞間通訊（GJIC）缺失的響應性降低所致。^1,10

產品特點

AldeRed ALDH檢測分析

癌癥干細胞醛脫氫酶（ALDH）的表達量升高，被認為是所有CSCs的標志。ALDEFLUOR™檢測試劑盒過去一直用于測量ALDH的表達水平，并廣泛用于研究罕見的CSC群體。ALDEFLUOR檢測試劑盒的發射波長位于電磁光譜的綠色區域（512nm）。因此，其中的試劑不能同時用于表達綠色熒光蛋白（發射綠色熒光光譜）的細胞或小鼠。AldeRed是用于標記活ALDH陽性細胞的ALDH紅移熒光底物，從而釋放出綠色發射通道以幫助同步完成其他檢測。AldeRed克服了ALDEFLUOR檢測試劑盒目前的局限。

閱讀《Nature》中關于AldeRed的文章

AldeRed的特性和優點：

• 紅移檢測釋放出其他實驗所需的綠色通道

• 活體干細胞鑒定技術，能夠對罕見的細胞群體進行流式分選

• 快速酶反應檢測方案

AldeRed 588-A是一種無毒的ALDH熒光底物，能夠自由進入完整活細胞但其被ALDH轉化成酸產物后仍將滯留在細胞內。

癌癥干細胞信號轉導通路

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

Hedgehog 和 Bmi1通路

Hedgehog（Hh）通路能夠調節成體干細胞的休眠和自我更新。研究人員已經在哺乳動物中鑒定了三種Hh配體，即Sonic hedgehog（Shh）、Desert hedgehog（Dhh）和Indian hedgehog（Ihh），其中對Shh的研究多。在沒有配體的情況下，Hh受體PTCH1通過催化抑制跨膜蛋白Smoothened（SMO），從而抑制信號轉導。配體與PTCH1可使受體失活，并活化SMO，繼而誘導Gli轉錄因子；Gli1和Gli2是Hh信號通路的陽性信號介導子，而Gli3是負調節子^3,20。

Bmi1的誘導能夠促進許多Hh活化的效應。Bmi1 是一個的多梳基因，通過染色質重塑抑制轉錄，并能夠下調Ink-4A / ADP核糖基化因子（ARF）復合物（如p16 Ink4A 和p19 ARF）的基因表達——這些基因是細胞周期的負調節物并且參與干細胞的休眠和分化^3,4。這使得Hh通路元件PTCH1、Gli1和Gli2表達上調^19,20， 以及Gli1和Gli2誘導的生長促進基因cyclin D1、Myc和Snail表達來實現干細胞分化和自我更新。

Notch-γ-分泌酶通路

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

Notch通路激活包括通過γ-分泌酶對Notch配體/受體復合物進行蛋白水解切割，從而釋放Notch胞內結構域片段（NICD），移位到細胞核并上調Myc、Hes1和其他基因的表達。當用NICD2轉染DAOY成神經管細胞瘤細胞系使Notch通路持續激活時，轉染后的細胞比非轉染的DAOY細胞產生更多的異種移植腫瘤，培養物中CD133 +和側群干細胞樣細胞也增加了。相反，抑制γ-分泌酶可將側群細胞減少至總細胞計數的0.01％，并且抑制90％的細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轉染可保護細胞免受γ-分泌酶抑制的影響¹⁵。因此，在一些腫瘤類型中，抑制Notch信號轉導可以消除腫瘤起始所需的細胞群。

Wnt-β-連環蛋白途徑

Wnt包含結合Frizzled（Fz）受體家族的19種胞外糖蛋白家族，其可激活抑制β-連環蛋白的蛋白水解降解途徑，這使得β-連環蛋白在細胞質中積累并向細胞核轉運。在細胞核中，β-連環蛋白通過Tcf / Lef轉錄因子促進基因轉錄。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）形成復合物，從而促進細胞質β-連環蛋白磷酸化，繼而靶向β-連環蛋白以進行蛋白水解降解。

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））的結合。Wnt / Fz / Lrp5 / 6復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復合物。Lrp5 / 6被Gsk3和酪蛋白激酶1γ（Ck1γ）。 磷酸化的Lrp5 / 6結合Axin / Gsk3形成復合體，防止β-連環蛋白的磷酸化從而穩定β-連環蛋白。

圖1. 癌癥干細胞中關鍵發育信號轉導通路的激活。Shh、Wnt和Notch信號轉導途徑與維持癌癥干細胞的致瘤潛力有關。通過與Bmi1信號轉導介體和其他自我更新基因（如Nanog和Sox-2）的相互作用，這些新的調節機制可以促進或抑制自我更新，從而提供癌癥治療干預的方法。

材料

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

參考文獻

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