Hacking bacteria to fight cancer - Tal Danino

Prevodilac: Aleksandar Bošnjak Lektor: Ivana Korom

In 1884, a patient’s luck seemed to go from bad to worse.

Godine 1884. sreća jednog pacijenta je čini se od loše postala još gora.

This patient had a rapidly growing cancer in his neck,

Ovaj pacijent je imao galopirajući rak u vratu,

and then came down with an unrelated bacterial skin infection.

a onda je dobio i nepovezanu kožnu bakterijisku infekciju.

But soon, something unexpected happened:

Malo nakon toga, desilo se nešto neočekivano:

as he recovered from the infection, the cancer also began to recede.

kako se oporavljao od infekcije, rak je krenuo da se smanjuje.

When a physician named William Coley tracked the patient down 7 years later,

Kada je lekar Vilijam Koli našao pacijenta sedam godina kasnije,

no visible signs of the cancer remained.

nije bilo vidljivih tragova raka.

Coley believed something remarkable was happening:

Koli je verovao da se nešto izvanredno dešavalo,

that the bacterial infection had stimulated the patient’s immune system

a to je da je bakterijska infekcija stimulisala imuni sistem pacijenta

to fight off the cancer.

da se bori protiv raka.

Coley’s fortunate discovery led him to pioneer

Kolijev srećan pronalazak doveo ga je do toga da razvije

the intentional injection of bacteria to successfully treat cancer.

injekciju punu bakterija za uspešno lečenje raka.

Over a century later, synthetic biologists have found an even better way

Više od veka kasnije, sintetički biolozi su pronašli još bolji način

to use these once unlikely allies—

da koriste ove nekadašnje neprijatelje,

by programming them to safely deliver drugs directly to tumors.

programirajući ih da na siguran način direktno dostave lekove tumorima.

Cancer occurs when normal functions of cells are altered,

Rak nastaje kada se promene normalne ćelijske funkcije,

causing them to rapidly multiply and form growths called tumors.

što prouzrokuje da se brzo umnožavaju i stvaraju izrasline zvane tumori.

Treatments like radiation, chemotherapy, and immunotherapy

Lečenja kao što su radijacija, hemoterapija i imunoterapija

attempt to kill malignant cells, but can affect the entire body

pokušavaju da ubiju maligne ćelije, ali mogu da utiču na celo telo

and disrupt healthy tissues in the process.

i time poremete zdrava tkiva.

However, some bacteria like E. coli

Međutim, neke bakterije kao što je ešerihija koli

have the unique advantage of being able to selectively grow inside tumors.

imaju jedinstvenu prednost da selektivno rastu unutar tumora.

In fact, the core of a tumor forms an ideal environment

U stvari, srži tumora stvaraju idealno okruženje

where they can safely multiply, hidden from immune cells.

gde mogu da se neometano množe, sakriveni od imunih ćelija.

Instead of causing infection,

Umesto da prouzrokuju infekciju,

bacteria can be reprogrammed to carry cancer-fighting drugs,

bakterije mogu da budu programirane da prenose lekove za borbu protiv raka,

acting as Trojan Horses that target the tumor from within.

ponašajući se kao trojanski konj koji traži tumor iznutra.

This idea of programming bacteria to sense and respond in novel ways

Ova ideja o programiranju bakterija da opažaju i reaguju na nove načine

is a major focus of a field called Synthetic Biology.

je glavni fokus oblasti zvane sintetička biologija.

But how can bacteria be programmed?

A kako mogu da se programiraju bakterije?

The key lies in manipulating their DNA.

Ključ je u manipulisanju njihovom DNK.

By inserting particular genetic sequences into bacteria,

Ubacivanjem određenih genetičkih sekvenci u bakterije,

they can be instructed to synthesize different molecules,

one mogu dobiti uputstva da spajaju različite molekule,

including those that disrupt cancer growth.

uključujući one koji ometaju razvoj raka.

They can also be made to behave in very specific ways

Mogu da budu napravljeni tako da se ponašaju na veoma specifičan način

with the help of biological circuits.

uz pomoć bioloških kola.

These program different behaviors depending on the presence, absence,

Oni programiraju različita ponašanja u zavisnosti od prisustva, odsustva

or combination of certain factors.

ili kombinacije izvesnih faktora.

For example, tumors have low oxygen and pH levels

Na primer, tumori imaju malo kiseonika i male pH nivoe

and over-produce specific molecules.

i prozvode više posebnih molekula.

Synthetic biologists can program bacteria to sense those conditions,

Sintetički biolozi mogu da programiraju bakterije da opaze ove uslove,

and by doing so, respond to tumors while avoiding healthy tissue.

i odgovore tumorima izbegavajući zdrava tkiva.

One type of biological circuit,

Jedan tip biološkog kola poznat kao sinhronizovano kolo lize, ili SKL,

known as a synchronized lysis circuit, or SLC,

allows bacteria to not only deliver medicine,

dopušta bakterijama da dostave lekove i da to rade po rasporedu.

but to do so on a set schedule.

First, to avoid harming healthy tissue,

Prvo, kako bi izbegli oštećenje zdravih tkiva,

production of anti-cancer drugs begins as bacteria grow,

proizvodnja lekova protiv raka počinje kako bakterije krenu da rastu,

which only happens within the tumor itself.

a to se dešava samo unutar samog tumora.

Next, after they’ve produced the drugs,

Onda, nakon što proizvedu lekove,

a kill-switch causes the bacteria to burst

dugme za zaustavljanje uzrokuje da bakterije puknu

when they reach a critical population threshold.

kad dostignu prag kritične populacije.

This both releases the medicine and decreases the bacteria’s population.

Ovako ispuštaju lekove i u isto vreme smanjuju populaciju bakterija.

However, a certain percentage of the bacteria remain alive

Međutim, određeni procenat bakterija ostaje živ

to replenish the colony.

kako bi se ispunila kolonija.

Eventually their numbers grow large enough to trigger the kill switch again,

Vremenom se njihov broj dovoljno poveća da aktiviraju dugme za zaustavljanje

and the cycle continues.

i onda se ciklus nastavlja.

This circuit can be fine-tuned to deliver drugs

Ovo kolo se može podesiti da dostavlja lekove po bilo kom periodičnom rasporedu

on whatever periodic schedule is best to fight the cancer.

koji je najbolji za borbu protiv raka.

This approach has proven promising in scientific trials using mice.

Ovaj pristup se pokazao dobrim u naučnim ispitivanjima na miševima.

Not only were scientists able to successfully eliminate lymphoma tumors

Ne samo da su naučnici bili u mogućnosti da uspešno eliminišu limfome

injected with bacteria,

u koje su bile ubačene bakterije, već je injekcija stimulisala imuni sistem,

but the injection also stimulated the immune system,

priming immune cells to identify and attack untreated lymphomas

što je pripremilo imune ćelije da identifikuju i napadnu limfome

elsewhere in the mouse.

na drugim mestima kod miševa.

Unlike many other therapies,

Za razliku od drugih terapija, bakterije ne ciljaju na jedan specifičan tip raka,

bacteria don’t target a specific type of cancer,

but rather the general characteristics shared by all solid tumors.

nego na opšte karakteristike koje dele svi čvrsti tumori.

Nor are programmable bacteria limited to simply fighting cancer.

Niti su programirane bakterije ograničene da se samo bore protiv raka.

Instead, they can serve as sophisticated sensors

Umesto toga, one mogu da služe kao sofisticirani senzori

that monitor sites of future disease.

koji nadgledaju lokacije budućih oboljenja.

Safe probiotic bacteria could perhaps lie dormant within our guts,

Bezopasne probiotske bakterije bi mogle biti uspavane unutar naših stomaka,

where they’d detect, prevent, and treat disorders

gde bi detektovale, sprečile i lečile poremećaje

before they have the chance to cause symptoms.

pre nego što imaju šansu da prouzrokuju simtome.

Advances in technology have created excitement around a future

Napreci u tehnologiji su stvorili uzbuđenje oko budućnosti

of personalized medicine driven by mechanical nanobots.

personalizovane medicine kojima upravljaju mehanički nanoroboti.

But thanks to billions of years of evolution

Ali zahvaljujući milijardama godina evolucije

we may already have a starting point

možda već imamo polaznu tačku

in the unexpectedly biological form of bacteria.

u neočekivanoj biološkoj formi bakterija.

Add synthetic biology to the mix,

Dodajte sintetičku biologiju u sve to,

and who knows what might soon be possible.

i ko zna šta će uskoro biti moguće.