[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,Cancer affects all of us,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,especially the ones that come back\Nover and over again.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,The highly invasive \Nand drug-resistant ones,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,the ones that defy medical treatment,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,even when we throw our best drugs at them.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,Engineering at the molecular level,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,working at the smallest of scales,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,can provide exciting new ways
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,to find the most aggressive\Nforms of cancer.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,Cancer is a very clever disease.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,There are some forms of cancer,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,which, fortunately, we've learned\Nhow to address relatively well
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,with known and established drugs\Nand surgery.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,But, there's some forms of cancer\Nthat don't respond
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,to these approaches
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,and the tumor survives\Nor comes back,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,even after an onslaught of drugs.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,We can think of these\Nvery aggresive forms of cancer
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,as kind of super villains in a comic book.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,They're clever, they're adaptable,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,and they're very good at staying alive.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,And, like most super villains\Nthese days,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,their super powers come from\Na genetic mutation.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,The genes that are modified\Ninside these tumor cells
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,can enable and encode for new\Nand unimagined modes of survival,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,allowing the cancer cell\Nto live through
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,even our best chemotherapy treatments.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,One example is a trick \Nin which a gene allows
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,a cell, even as the drug\Napproaches the cell,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,to push the drug out before the drug\Ncan have any effect.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,Imagine the cell effectively\Nspits out the drug.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,This is just one example\Nof the many genetic tricks
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,in the bad of our super villain, cancer.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,All due to mutant genes.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,So, we have a super villain\Nwith incredible super powers
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,and we need a new and \Npowerful mode of attack.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,Actually, we can turn off a gene,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,the key is a set of molecules\Ncalled siRNA.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,siRNA are short sequences\Nof genetic code
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,that guide a cell to block\Na certain gene.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,Each siRNA molecule\Ncan turn off a specific gene
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,inside the cell.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,For many years since its discovery,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,scientists have been very excited
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,about how we can apply\Nthese gene blockers in medicine.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,But, there is a problem.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,siRNA works well inside the cell.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,But if it gets exposed to the enzymes\Nthat reside
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,in our bloodstream and our tissues,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,it degrades within seconds.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,It has to be packaged, protected\Nthrough its journey through the body
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,on its way to its final target\Ninside the cancer cell.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,So, here's our strategy:
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,first, we'll dose the cancer cell\Nwith siRNA, the gene blocker,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,and silence those viral genes,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,and they'll we'll whap (?) it\Nwith a chemo drug.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,But how do we carry that out?
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,Using molecular engineering,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,we can actually design \Na super weapon
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,that can travel through the blood stream.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,It has to be tiny enough\Nthat it can get through the blood stream,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,it's got to be small enough\Nto penetrate the tumor tissue,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,and it's got to be tiny enough\Nto be taken up
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,inside the cancer cell.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,To do this job well, it has to be\Nabout one 100th the size
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,of a human hair.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,Let's take a closer look\Nat how we can build this nanoparticle.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,First, let's start with \Nthe nanoparticle core.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,It's a tiny capsule that contains\Nthe chemotherapy drug.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,This is the poison that will\Nactually end the tumor cell's life.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,Around this core, we'll wrap\Na very thin,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,nanometer-think blanket\Nof siRNA.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,This is our gene blocker.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,Because siRNA is strongly negatively charged,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,we can protect it with a nice\Nprotect layer
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,of postively charged polymer.
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,The two oppositely charged molecules\Nstick together throough charge attracttion,
Dialogue: 0,9:59:59.99,9:59:59.99,Default,,0000,0000,0000,,and that provides us with a protective\Nlayer