when will we cure cancer?
1. what tuberculosis was to the 19th century, cancer is to the 20th. there may never be a single cure, one drug that will bring every cancer patient back to good health, in part because every type of cancer, from brain to breast to bowel, is different.
2. however, during the next 10 years, doctors will be given tools for detecting the earliest stages of many cancers and suppressing them before they have a chance to progress to malignancy. there is reason to hope that within the next 25 years new drugs will be able to ameliorate most if not all cancers and maybe even cure some of them. the main upshot of change is the sheer number of drugs in development--so many that they threaten to swamp clinical researchers' capacity to test them.
3. this boom in cancer drugs owes its beginnings to one of this century's greatest scientific insights: that cancer is caused not by depression or miasmas or sexual repression, as people at various times have believed, but by faulty genes. every tumor begins with just one errant cell that has been unlucky enough to suffer at least two, but sometimes several, genetic mutations. those mutations prod the cell into replicating wildly, allowing it to escape the control that genes normally maintain over the growth of new tissue.
4. this realization has transformed cancer, in little more than a decade, from a mysterious disease into a disorder whose molecular machinery is largely understood. now cancer biologists are in the midst of their second epiphany: the recognition that tumors evolve, in darwinian fashion, as each succeeding generation of cancer cells accumulates genetic mutations. "survival of the fittest applies to cancer cells," says richard schilsky, associate dean for clinical research at the university of chicago. "we now think of cancer not as a disease but as a genetic process."
5. this new view has sparked innovations that will manage the process and keep it from killing large numbers of people. "we are going to see a real shift from diagnosis and treatment to prediction and prevention," declares california surgeon susan love, author of dr. susan love's breast book. indeed, if all goes well with current clinical trials, women at high risk for breast cancer will soon be able to be screened with a device that removes a sample of breast cells through the nipple. if any cells show signs of the early mutations that lead to cancer, doctors can suggest the drug tamoxifen, which is believed to reduce the risk of breast cancer by suppressing precancerous cells. drugs with fewer side effects that can also prevent breast cancer are already in the pipeline.
6. within five years, early detection will be available for many other types of cancer as well. a stool sample will be all that is needed to search for colon-cancer cells on their way to becoming tumors, and drugs like the new cox-2 inhibitors, which are improved versions of pain killers, can prevent those precancerous cells from progressing. by the end of the next decade, a simple blood test could alert doctors to a wide variety of cancer precursors.
7. treatments for more advanced cancers, however, are farther over the horizon than anybody can see. oncologists must try to outsmart tumors that have already begun to metastasize. that's because a tumor is made up of a hodgepodge of cells containing different genetic mutations, each of which allows it to wreak a different brand of havoc. some mutations spur rapid growth; others prod nearby blood vessels into sprouting new capillaries; still others send cancer cells out into the bloodstream, where they can seed new tumors. within 10 years, predicts robert weinberg, a cancer biologist at the whitehead institute in cambridge, mass., "we will analyze the mutant genes and then tailor-make a treatment (for) that particular tumor."
8. one day there will be drugs to trip up a cell at each of the steps it takes on the path to malignancy. a patient with lung cancer, say, might undergo gene therapy, breathing in genetically altered cold viruses that don't cause infection but instead act as miniature delivery vans carrying copies of the p53 gene. good copies of this gene, which is mutated in many cancers, can force some cancer cells to commit suicide. the effects of p53 could be bolstered with antibodies that slow tumors by attaching to the surface of cancer cells and gumming up their ability to take over the body's growth factors, the specialized proteins that promote cell reproduction.
9. if a tumor has acquired the mutations for spreading, the doctor of the future may call on a new kind of drug that can be taken orally to block the enzymes a tumor uses to break down the cells of surrounding tissue and invade it. vaccines cobbled together from whole cancer cells or bits and pieces of those cells have been shown to boost the body's immune system, helping it recognize and kill tumors on its own.
10. also close to reality are the so-called antiangiogenic factors, relatively nontoxic compounds that inhibit the growth of new capillaries. the idea behind this new class of drugs is that tumors cannot grow bigger than a few hundred thousand cells--about the size of a peppercorn--without growing their own blood-supply system. researchers and patients are eagerly awaiting results of clinical trials of antiangiogenic factors, which might be used in combination with chemotherapy to knock down big tumors and then prevent any surviving tumors from growing enough to do further damage.
11. certain cancers may require treatment for the rest a patient's long life. this may be hard to imagine. but turning cancer into a controllable condition is not so different from treating high blood pressure or diabetes. says ellen stovall, executive director of the national coalition for cancer survivorship," (the goal) should be helping people live as long and as well as they can."
12. no, we probably won't cure all forms of cancer in the 21 st century. but we may very well learn to live with them.
参考译文：我们何时能治愈癌症
1．如果说结核病属于19世纪，那么癌症则是属于20世纪的疾病。也 许永远不会有一种单独的疗法，即一种药能够使所有的癌症患者康复。其部 分原因是每一种癌，从脑癌、乳腺癌到肠癌都是不同的。
2．然而，在下一个十年，医生将会使用各种方法对很多癌症作出早期诊 断，并在癌细胞还没有恶化的时候加以抑制。我们有理由希望25年之内新出 现的药物能够治疗大部分癌症，甚至根治某些癌症。转机主要表现在大量药 物正在开发中，其数量之多使临床研究人员几乎无力应付。
3．癌症药物的迅猛发展，归功于本世纪最重要的科学见解之一：癌症并 不是像人们以往想象的那样由于抑郁、空气污染或禁欲造成，而是由变异的 基因造成的。任何肿瘤都开始于某一个不幸产生至少两个或几个基因变异的 细胞。这些变异刺激细胞大规模复制，使它能摆脱新组织生长过程中基因通 常保持的控制。
4．在仅仅十年时间里，这种认识将癌症从一种神秘的疾病改变成其分子 机制大半可以掌握的疾病。目前癌症生物学家正处于第二阶段的深入研究： 认识到肿瘤的发展符合达尔文进化方式，就是一代一代的癌细胞聚集变异。 芝加哥大学临床研究副院长理查德·希勒斯基说：“适者生存的理论也适合于 癌细胞。我们现在不把癌看成疾病，而是看成基因生长过程。”
5．这—新的观点激起的技术革新，将使我们能掌握基因的生长过程，阻 止它对很多人产生伤害。“我们将从诊断和治疗真正转变为预报和预防。”加 利福尼亚州的外科医生和《苏珊·洛夫医生论乳腺癌》一书的作者苏珊·洛 夫这样说。的确，如果目前临床实验顺利进行，有高风险患乳腺癌的妇女不 久就可以使用——种装置，从乳头做取样化验。如果有任何细胞呈现早期致癌 的变异，医生可建议使用它莫西芬，这是一种有效抑制早期癌细胞的药，可 减少癌病的发生。能防-上癌病发生而副作用少的药物正在研制中。
6．五年之内，还可以实现对很多癌症的早期诊断。一次大便采样就足以 对肠癌细胞是否会发展成为肿瘤作出诊断，新药cox-2抑制剂是改进的止 痛药，可防止：早期癌细胞的生长。十年以后，医生可以从简单的血样化验中 预知更多种的早期癌症。
7．对较晚期癌症的治疗仍然遥遥无期。癌病医生们必须采取更有效的办 法来对付肿瘤的转移。因为肿瘤是不同的基因变异细胞组成的混合物，每一 个细胞会产生不同的混乱变异。一些变异的细胞快速生长，另一些则刺激附 近的血管生长出新的毛细血管，其它的则使癌细胞进入血循环并生成新的肿 瘤。麻省剑桥怀特黑德研究院癌病生物学家罗伯特·温伯格预言：“十年之内， 我们将能够分析变异的基因，然后针·对特定的肿瘤制定出专门的治疗方案。”
8．总有—天，会有这样一种药，它可以使一个产生癌变的细胞在任何阶 段发生错误。例如，肺癌病人可以做基因治疗，吸入不会导致传染的遗传转 变基因冷冻病毒，这些病毒就像是一辆装满p53基因的微型货车一样。这一 基因的复制品在很多种癌症中产生好的变异，能迫使一些癌细胞自行死亡。 p53还可以与抗体’一起发挥更大的作用，它们附着在癌细胞的表面，减弱癌 细胞将促进细胞繁殖的特别的蛋白质取而代之的能力。
9．如果某个肿瘤已发展为可以转移的变异，未来的医生可以采用一种新 型的口服药来抑制肿瘤用以破坏侵入周围组织细胞的酶。这是一种由全部癌 细胞或部分癌细胞制成的疫苗，可增强人体免疫系统的能力，使其能够自己 辩认并变异细胞。
10．所谓抗淋巴因子也指日可待，这是一种相对无毒的化合物，可以阻止 新的毛细血管生长。这种药依据的是，没有供血系统的生长，肿瘤不会发展 到几十万个细胞——约有胡椒子那样大。研究人员和患者都在期待抗淋巴因 于的临床实验结果，这种药可能会与化疗结合使用，用于治疗大肿瘤并随后 坊止任何存活的肿瘤进一步生长而导致伤害。
11．一些癌病患者可能需要在其生命中长期接受治疗。这恐怕难以想象。 怛是将癌病维持在可控制的状态与治疗高血压和糖尿病没有很大的区别。美 国国家癌病生存联合会执行理事埃伦·斯托瓦尔说：“我们的目标是帮助人们 尽量生活得更好和更长久。”
12．在21世纪，我们可能不会治愈所有的癌病，但是我们可以很好地与它们共存。