- [Instructor] Lecture 13 quiz review
is gonna be on cancer, which
generally people do well on,
but there are a few odds and
ends that you have to pay
close attention to, so let's begin.
One of the first questions
you're gonna have
on cancer is how they're classified,
and it generally comes from this list.
So just be familiar with
how we classify cancer.
The second one is actually
going to apply what you learned
from benign and malignant tumors,
in that benign stay in
their site of origin,
where malignant metastasize.
And in those, I'll use
these classic cancer
classifications as examples
to say things like,
"Oh, a melanoma in the kidneys."
Well, that would be an example
of one that's metastasized,
because melanocytes are
supposed to be in the skin!
And when they migrate out
and go into other parts of the body,
that means that they've metastasized,
they're no longer benign.
Other ones may say,
"This type of cancer is associated
with freckles and moles."
Again, that's a melanoma,
because melanocytes are associated
with freckles and moles.
So there are a couple of different
questions in there designed
to basically test you
on a couple of different ones.
I can't go through all the cancers,
'cause there's like 256 different types
of cells in the human body.
And so there's a lotta cancers out there.
Basically, you just need
to know the fundamental
principle of why we call
them the names that we do.
It's generally after the name
of the cell, like leukocytes,
or after the name of the
organ that they're found in,
like we could say pancreatic carcinoma,
and that's why the word carcinoma was used
as a general term for cancer.
And just giving the nomenclature
of the organ before that.
The next set of questions
are gonna be on these
first four modes of cancer treatment.
The other, the last three, immunotherapy,
targeted therapy, stem cell,
these are things that are
just kinda New Age ones
that I don't really care,
that'd part of the core curriculum,
but they are the next-generation ways
of trying to treat cancer,
but these first four,
surgery, radiation, chemo, and hormone,
generally, people mix
up radiation and chemo.
So pay close attention to those.
Again, radiation only damages
DNA to trigger apoptosis.
That's generally this
checkpoint right here
in the cell cycle to
make sure that the DNA
is able to be copied
without any major mistakes.
And this is one of those
checkpoints that will induce
apoptosis if it doesn't pass that.
Well, that's one of the things
that radiation therapy triggers,
is damaging the DNA so that you trigger
apoptosis in the cancer.
Chemotherapy, again,
are enzyme inhibitors.
They are essentially things
that block key enzymatic
processes in the cell
and induce apoptosis, and
the range of these drugs,
there's over 7,000 that
the FDA's approved.
So there are a lot of different drugs
that are used to administer,
to treat cells that are rapidly growing.
Remember that hormone therapy
is basically a disruption
of the hormones that tell
the cells to grow rapidly.
It's not that the cells
themselves are problematic,
it's that your hormones
are out of balance.
And this is used to disrupt the signals
that basically tell the
cells to divide rapidly.
Another two questions you're gonna have
are on cancer cell characteristics.
So make sure you know
what cancer cells are,
and what they are not.
This is what they are.
They look differently, they
lack contact inhibition.
They have limitless replication potential
because of the telomere shortening.
They evade some apoptotic triggers.
Not all, just some.
So look for the contrast,
that normal cells are specialized,
that they have contact inhibition,
that they have limited
replication potential,
and that they don't evade,
that they keep all of
their apoptotic programming
to be able to respond to any problems
that arise from the cells.
Now other than questions you'll
have will be on telomeres,
or angiogenesis or apoptosis.
These are terms that I'll describe,
and you will choose those from a list.
So those aren't too
difficult, you just make sure
you understand what they are
and what we've talked about.
Now, the last questions you're gonna have,
these are the last about
three questions or so,
are on the genetic causes of cancer.
And this is where you need
to make sure you understand
that these are groups of genes.
Basically, proto-oncogenes
are groups of genes that collectively
promote the cell cycle
and prevent apoptosis.
And tumor suppressor
genes are groups of genes
that inhibit the cell cycle
and stimulate apoptosis.
When you mutate proto-oncogenes,
they become oncogenes.
When you mutate tumor suppressor genes,
we call them mutated
tumor suppressors, right?
So one oncogene is enough to...
It's like putting your foot on the gas.
But in order for tumor suppressor genes
to combine to make it a
problem, you have to have both,
'cause you have two copies of every gene.
You gotta have both of the copies
mutated to cause a problem.
'Cause it's like you
have redundant brakes.
You have two sets of these
genes, and if one's a problem,
another one can basically
compensate for it,
but when both of them are problematic,
the combined effect,
that's what causes cancer.
And this is a possible
question on the quiz, too!
It's oncogenes and mutated
tumor suppressor genes,
that's ultimately what
leads to some of the genetic
causes of cancer that
you'll be looking out for.
The last question, fundamentally,
comes down to the concept
of passing cancer on,
from generation to generation.
You don't actually pass the cancer on,
you pass the predisposition to cancer on,
because you're passing the genes on,
you're passing on the oncogenes,
the mutated tumor suppressor genes.
And this just gets you one step closer
to uncontrolled cell
growth that can happen
sometimes very early on in a
child's life, unfortunately.
And so that's one of the
questions that I'll ask,
is that they can only
be these mutated genes
that are passed on through the gametes.
If you have skin cancer and have a kid,
you're not gonna pass those genes
that mutated in your skin on to your kid.
They can only be passed
on through the sperm
or the egg of genes that you inherited,
or new mutations that may have occurred
in your gametes, and that's rare.
Generally they're passed
on from generation
to generation from a long time ago.
So that's the outline for the cancer.
Make sure that you get each
one of those things in check,
and most of them are
pretty straightforward,
but the genes are the
ones that people generally
have the most difficulty with.
