Biochemistry of Cancer

Introduction
-
:

The term derived Latin

from
'
wi Sanskrit
'

Can crum
°
= n
cancer

Greek =
Kar Kino ma = Kar Kita Kam ( crab)
.
All cancers are
multifactorial in
origin
.

They include Genetics hormonal metabolic

physical chemical &
•

, , ,
,

environmental
factors
.

o Most human cancers are

spontaneous .

•
All cancers
originate from one aberrant cell ,
which
goes
on to

multiply and
produce tumor mass .

Mutagens :
Any
substance which increases the rate
of
mutation can

enhance the rate incidence

also
of of cancer .

All
carcinogens Mutagens
•
are .

Examples -
X -

Rays y rays UV chemicals ( tobacco

rays
-

, .
, ,

aflatoxin
etc )

Antonieta gens
cis Vit A & carotenoids shown to
precancerous conditions
are reverse .

Vit E acts antioxidant

ai; as
,
preventing damage made by free radicals
and oxides
super
.

( iiis tit c
prevents cancers in
working
persons
with aniline .

( in Curren min in Turmeric cis

known to prevent cancers .

diet decreases the risk

as low
protein ,
low
fat of cancer in

animal studies .
 µ, flavin oils are
phytochemicals that
posses
anti
mutagenic properties .

(vill Phenolic
compounds are
effective in
fighting mutagens .

( found in
grapes
,
walnuts )

"" " '

Green tea induced mutations
in
effective against smoke .

Oncogene Viruses
°
Another etiological factor of carcinogenesis in the
integration
of viral
genes
into host DNA .

Oncogenes
Normal Constituents cells
Oncogenes of
°
are .

genes capable of
These
causing
°
are cancer .

and denoted
°
To
distinguish viral
gene
cellular
gene ,
they are V -
src &

C
respectively
src
-

oncogenes present
•
The in normal cells are also called as

proto oncogenes
-
.

Today more than too human

proto -

oncogenes
are
known .
 Growth Factors
Many oncogenes through act
°

the
production of growth factor .

•
These may be considered as

local hormones .

• There are more than too

growth factors .

Interleukin and
interferons growth factors released
by
°

are

lymphocytes / macrophages .

Difference between Normal & Tumor Cells .

in
Doubling Time : gt can
vary widely between lo
days to 450
days
with a mean
of about too
days in Tumors cells .
 (2) Contact Inhibition lost
This
property is in cancer cells
-
.

131
Anchorage Dependence Malignant character is the loss of
-

anchorage dependence in tissue culture system .

( 41 Most cancer cells

carry negative surface charges
more on their
due
cell
surface than their normal
counterparts This in .
to

neurami acid ) content

higher MAMA ( N -

acetyl of cancer
membrane
cell
.

151 Cancer cells have a

tendency to
disintegrate from main mass

and to disseminate to distant

nearby or
organ
This is
.

called Metastasis .

161 Cancer cells have increased and

persistent activity of telomerase ,

the that maintains the

enzyme length g telomeres .

Tumor
Maar Kers
called
They are also tumor indene substances
•
as
.

which could be
•

They are
factors released
from the tumor cells ,

detected in blood and

therefore indicate
presence og
tumor in
body .

They are
useful for the
following purposes
:

and
For
follow -

up of cancer to monitor the

effectiveness of
therapy .

do , To facilitate detection
of cancer .

For
(c)
prognosis
.

(d) Precautions -
Tumor
markers are sometimes elevated in

conditions
nonmalignant .

• lather a
marker in med
for cancer
screening or
diagnosis ,

the test result

physician must
confirm a tire
by using
studies tissue biopsies & other procedures
imaging
.

,
Anti -
cancer
Drugs :
-

② Med Notes ( med notes . in )

-