癌症，这个人人闻之丧胆的疾病，在现代社会中显得越来越常见。我们都害怕琳琅满目的加工食品、电子用品、工业建设、或是环境污染会把癌症带入你我的生命中，但恐惧与拒斥并不会因此保护我们免于伤害！
不久前，TED-Ed (Technology, Entertainment, Design) 运用大家常见到的物品，如毛线与谷类为素材，来表现人体组织与细胞的各式样态，使我们大家暂时抛开恐惧，冷静且客观的认识癌细胞的形成、以及对付它的方式。
注：以下是上面视频的中英对照稿
撰稿及翻译：刘耘
We all start life as one single cell. Then that cell divides. And we are two cells, then four, then eight. Cells form tissues, tissues form organs, organs form us. These cell divisions, by which we go from a single cell to 100 trillion cells, are called growth. And growth seems like a simple thing because when we think of it, we typically think of someone getting taller or, later in life, wider, but to cells, growth isn’t simple.
所有的生命起源都来自一个细胞。他分裂成两个、四个、八个…细胞逐渐形成组织，组织形成器官，而器官便构成了我们的身体。单一细胞逐渐分裂成十兆个细胞的过程就叫做「成长」。提及这个词，我们总是想得很简单：一般都会想到某人长高了、变壮了，但对细胞来说，成长可不是这么简单的一件事。
Cell division is an intricate chemical dance that’s part individual, part community-driven. And in a neighborhood of 100 trillion cells, sometimes things go wrong. Maybe an individual cell’s set of instructions, or DNA, gets a typo, what we call a mutation. Most of the time, the cell senses mistakes and shuts itself down, or the system detects a troublemaker and eliminates it. But, enough mutations can bypass the fail-safes, driving the cell to divide recklessly. That one rogue cell becomes two, then four, then eight. At every stage, the incorrect instructions are passed along to the cells’ offspring.
细胞分裂就像一场繁复的化学舞蹈，一部分是独立运作，某部分又由群体所主导。在一个拥有十兆个居民的细胞群体中，有时难免会出些差错。我们所称的「突变」就是细胞中控制著生命密码的 DNA 出了错。大部分的时候，细胞会侦测出这些变异并自行消灭它，或者系统也会侦测并消除掉突变的细胞；然而，突变的数量若是够多，这些变异的细胞就可能会通过这些防御机制，恣意地进行细胞分裂。一个突变的细胞就这样分裂成两个、四个、八个… 。每一个阶段，细胞中的错误指令就被传了下去。
Weeks, months, or years after that one rogue cell transformed, you might see your doctor about a lump in your breast. Difficulty going to the bathroom could reveal a problem in your intestine, prostate, or bladder. Or, a routine blood test might count too many white cells or elevated liver enzymes. Your doctor delivers the bad news: it’s cancer.
随著时间推移，这个细胞也许就形成了你乳房中的肿块；如厕时的困难可能肇因于肠子、前列腺、或是膀胱；或者，进行健康检查时可能检验出血液中过多的白血球或升高的肝脏酵素。此时，医生便宣布了一个坏消息：这是癌症。
From here your strategy will depend on where the cancer is and how far it’s progressed. If the tumor is slow-growing and in one place, surgery might be all you need, if anything. If the tumor is fast-growing or invading nearby tissue, your doctor might recommend radiation or surgery followed by radiation. If the cancer has spread, or if it’s inherently everywhere like a leukemia, your doctor will most likely recommend chemotherapy or a combination of radiation and chemo. Radiation and most forms of chemo work by physically shredding the cells’ DNA or disrupting the copying machinery. But neither radiation nor chemotherapeutic drugs target only cancer cells. Radiation hits whatever you point it at, and your blood stream carries chemo-therapeutics all over your body.
情况发展至此，你就得依照癌细胞的位置以及生长状况对症下药。若肿瘤生长缓慢且只生长在某个部位，动个手术也许就能解决掉它；若肿瘤生长快速且侵略了周围的组织，医师也许会建议使用放射治疗、或是先进行手术切除后再做放射治疗；若癌细胞已经扩散，或者罹癌的部位本身就是遍布全身（例如血癌），医生可能会建议进行化学治疗、或是放射治疗与化疗同步进行。放射治疗与大部分的化疗会破坏掉细胞的 DNA 、或捣乱细胞复制的程序，但这两种治疗锁定的细胞都不只是癌细胞而已。放射治疗会攻击所有放射线照射到的部位，而血液则会把化学疗程的药物带至全身。
So, what happens when different cells get hit? Let’s look at a healthy liver cell, a healthy hair cell, and a cancerous cell. The healthy liver cell divides only when it is stressed; the healthy hair cell divides frequently; and the cancer cell divides even more frequently and recklessly.
那么，癌细胞与正常细胞对于这些治疗的反应各是如何呢？让我们来看看健康的肝细胞、头发细胞、与癌细胞吧。健康的肝细胞只在器官有所损伤时进行复制，头发细胞则是无时无刻都在分裂增生，而癌细胞生长的速度比起正常细胞更快、更疯狂。
When you take a chemotherapeutic drug, it will hit all of these cells. And remember that the drugs work typically by disrupting cell division. So, every time a cell divides, it opens itself up to attack, and that means the more frequently a cell divides, the more likely the drug is to kill it.
当你进行化疗时，药物会攻击所有细胞，而药物的作用是捣乱细胞分裂的程序。也就是说，每一次细胞开始分裂时就是药物产生作用的时候，而分裂频率越高的细胞就会引发越多次的药物攻击。
So, remember that hair cell? It divides frequently and isn’t a threat. And, there are other frequently dividing cells in your body like skin cells, gut cells, and blood cells. So the list of unpleasant side effects of cancer treatment parallels these tissue types: hair loss, skin rashes, nausea, vomiting, fatigue, weight loss, and pain. That makes sense because these are the cells that get hit the hardest.
记得头发细胞吗？它分裂的很快、但并不对身体造成威胁，且身体中存在著其他分裂频繁的细胞，像是皮肤细胞、内脏细胞、血液细胞。因此，治疗癌症时常见的副作用就反应在这些部位，像是伴随而来的掉发、起疹子、恶心、呕吐、疲倦、体重减轻、疼痛等，原因正是因为这些细胞分裂的次数非常频繁。
So, in the end, it is all about growth. Cancer hijacks cells’ natural division machinery and forces them to put the pedal to the metal, growing rapidly and recklessly. But, using chemotherapeutic drugs, we take advantage of that aggressiveness, and we turn cancer’s main strength into a weakness.
总结来说，癌症与「成长」紧密相连。癌症绑架了细胞自然的分裂机制、逼迫它们任意的胡乱成长。而藉由化疗的药物，我们就能控制它侵犯细胞的速度，将癌细胞分裂快速的特性转变成它最大的弱点。
有一天化疗放疗都针对性更强就好了~~ 可惜没那么快啊~·
那是好，就不要突然变异乱吃就糟了~~
