BBC Focus - 04.2020_

Q&A

We’vejoinedforceswiththeteambehindBBCWorldService’sCrowdSciencetoansweryour

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Marnie Chesterton is a presenteronCrowdScience

CROWDSCIENCE

records.It’spossiblethatinages

wherepopulationswereravagedby

war,plaguesandotherinfections,

deathratesweresohighthat

cancer,oftenanage-related

disease, was scarce.

HOWDOES CANCER

S TA RT?

Almostallthecellsinourbody

needtodivide:it’showwegrow,

andhowwerepairdamagedtissue

andworn-outcells.Todothis,the

cell’sDNAmakesa copyofitself,

andmistakescanhappeninthis

process.These‘mutations’are

common,andourbodycanrepair

them.Butrarely,themutations

takeplaceina partoftheDNAthat

controlscelldivision,andthecells

don’tstopdividing.Thesecancer

cellscaneventuallyforma tumour,

andthecancercanspread to other

parts of our body.

CAN WE BEAT IT?

Oneofthemostpromisingareasis

immunotherapy,whichharnesses

thepatient’sownimmunesystem

tofightthecancer.A study

publishedinFebruarythisyear

usedengineeredbacteriatofind

andentertumours,wherethe

bacteriacoulddeliverdrugsthat

helptheimmunesystemto

recogniseandattackcancercells.

Earlydiagnosisis alsoimportant.

Thesooneryoucatcha cancer,the

lesschanceit hastoevolveinto

somethingmoredifficulttotreat.

Anotherstudypublishedin

Februaryrevealedthecomplete

DNAsequences(genomes)ofover

2,600tumours,helpingtopindown

thedifferentcombinationsofDNA

mutationsthatcanleadtocancer.

It’shopedthatthisresearchcould

helpdoctorstofindandtreat

cancermuchearlierinits

development– perhapseven

preventing it before it starts.

HASCANCER

ALWAYSBEEN

AROUND?

There’sa typeofmedical

archaeology,calledpalaeo-

oncology,whichsearches

throughourhistoricalrecords

forsignsofcancer.Possibly

theearliestreferencecomes

fromtheAncientEgyptian

physicianImhotep,wholived

around 2600 BC.Hewrote

about“bulgingmasseson

[the]breast”.Evenfurther

back,evidenceofcancerhas

beenfoundinthefootboneof

anancienthumanrelative

wholivedinwhatis now

SouthAfrica,1.7millionyears

ago.Socanceris nota modern

disease.Buttherearetimesin

ourhistorywhenthedisease

is not mentioned in the

WHAT IS CANCER?

ADAMKING,HUDDERSFIELD

WHAT’STHEMOST

ABUNDANTPARTICLE

IN THE UNIVERSE?

Measurementsoftheheat
leftoverfromtheBigBang
suggestthereareabout 1090
photonsintheUniverse–
makingthemaround 10
billiontimesmoreabundant
eventhanhydrogenatoms.
Butwhilephotonsarethe
mostnumerousknown
particle,theUniversealso
containsso-called‘dark
matter’,whosecompositionis
a mystery.Onepossibilityis
thatit’smadeupofparticles
calledaxions,whosemass
maybesolowthattheycould
onlyaccountfordarkmatter
byexistinginlargernumbers
even than photons.RM

Thelengthoftime,in

years,thatLegocan

surviveina marine

environment.

1,300

GETTY IMAGES X12 ILLUSTRATION: DANIEL BRIGHT