[drj10]

quick test: whats the disease associated with cyclin D guys ?

is it multiple myeloma?

I was doing research earlier on google while studying cyclins & CDKs ...

one source says "Cyclin D1, D2, or D3 expression appears to be increased and/or dysregulated in virtually all MM tumors despite their low proliferative capacity."
Other sources say leukemias & lymphomas ( so its ass w/ cancers- blood mostly). If u find out something..let me know.

This cellular stuff is complex :toosad: Iam going to now just stick to FA & DIT highlights on this cellular biology--already wasted lot off time on it.

 

[Dr.NickRiviera]

****, bcl-1 is in mantle, not burkitts

so the answer is Mantle cell lymphoma? (had to check FA to see where bcl-1 is but i do recall from kaplan bcl-1 is linked to cyclin D... i think lol)

 

[Hope2Pass]

Yup, The answer is Mantle cell lymphoma; t(11:14). Chr 11 has bcl-1 (Cyclin D) which gets translocated to Chr 14 (IgG heavy chain - which is always active)...This results in Cyclin D hyperactivity

In Burkitts, its t(14:18) where Chr 18 is bcl-2 which gets translocated to Chr 14 (IgG heavy chain) and leads to bcl-2 activation which then inhibits apoptosis by blocking the bax channel.

Whats the mechanism of Cyclin D? Its an oncogene that phosphrylates RB gene leading to its activation which causes cells to move from G1 to S phase?

 

[Hope2Pass]

And sorry, I didn't mean to take this thread out of its context of DIT !! I was just testing hehe Happy-2

 

[drj10]

And sorry, I didn't mean to take this thread out of its context of DIT !! I was just testing hehe Happy-2

No worries, the q is in context to todays lecture...the Cyclins stuff was not clearly explained by dr.jenkins & the DIT notes given were too intense, so i was doing my own little research.Thanks for stretching our brains.

 

[Dr.NickRiviera]

In Burkitts, its t(14:18) where Chr 18 is bcl-2 which gets translocated to Chr 14 (IgG heavy chain) and leads to bcl-2 activation which then inhibits apoptosis by blocking the bax channel.

burkitts is 8:14, no? c-myc activation? which is increased transcription?

the mechanism you described is follicular lymphoma if i recall correctly, in which its 14:18 translocation that results in bcl-2 overactivity and hence apoptosis inhibition (since cytochrome c cannot leave mitochondria). i dont think it affects BAX.

 

[Dr.NickRiviera]

Whats the mechanism of Cyclin D? Its an oncogene that phosphrylates RB gene leading to its activation which causes cells to move from G1 to S phase?

i think cyclin D phosphorylates and thereby inactivates Rb. since Rb (like p53) is a tumor-suppressor gene, you are removing the suppression of tumor proliferation, so cells proliferate freely.

 

[Hope2Pass]

burkitts is 8:14, no? c-myc activation? which is increased transcription?

the mechanism you described is follicular lymphoma if i recall correctly, in which its 14:18 translocation that results in bcl-2 overactivity and hence apoptosis inhibition (since cytochrome c cannot leave mitochondria). i dont think it affects BAX.

Ah yes you are right. Sorry, my brain was still hung up on Burkitts coz I had just read about it! This is follicular lymphoma.

i think cyclin D phosphorylates and thereby inactivates Rb. since Rb (like p53) is a tumor-suppressor gene, you are removing the suppression of tumor proliferation, so cells proliferate freely.

Yeah, that's right. Just looked it up as well...Phosphrylation of Rb gene makes it inactive. Makes sense.

 

[drj10]

Ah yes you are right. Sorry, my brain was still hung up on Burkitts coz I had just read about it! This is follicular lymphoma.

Yeah, that's right. Just looked it up as well...Phosphrylation of Rb gene makes it inactive. Makes sense.

Friends, keep the qs coming...best way to keep us challenged on this cellular stuff. Not too difficult ones though( Phd level))

Iam moving on to last lecture of the day - Neuro...it is a 3.5 lecture topic....so will continue on for tomorrow almost entire day.

 

[drj10]

not able to focus on neuro now...will do some revision of todays lecture, do some qs & go to bed...will start neuro fresh tomorrow. GN

 

[drj10]

One Q--what disease(s) are associated with mutations of Nuclear Lamins ?

 

[jijiji]

Hi...sorry for this silly question but can u tell me what DIT stands for.
Just now getting ready for usmle preparation so I beleive I have youe understanding.
thnx.

 

[drj10]

Hi...sorry for this silly question but can u tell me what DIT stands for.
Just now getting ready for usmle preparation so I beleive I have youe understanding.
thnx.

http://www.doctorsintraining.com/usmle

 

[Dr.NickRiviera]

One Q--what disease(s) are associated with mutations of Nuclear Lamins ?

ummm lamins are the filaments of the nuclear envelope and DNA within the nucleus... not sure what disease would result from their mutation.

 

[drj10]

couldn't sleep well last night, had to take anti-histamine at 4 am , woke up @ 11.30. I was doing good waking up early lately....I soo dont want become a night owl again.
Starting today w/ neuro..day 11 vid 3.

 

[drj10]

ummm lamins are the filaments of the nuclear envelope and DNA within the nucleus... not sure what disease would result from their mutation.

Progeria and Muscular dystrophy...DIT. yup, nuclear lamins are intermediate filaments of nuclear envelope & DNA within and cyclin B-CDK1 complex help in the breakdown of nuclear lamin and initiation of mitosis.

 

[Hope2Pass]

Progeria and Muscular dystrophy...DIT. yup, nuclear lamins are intermediate filaments of nuclear envelope & DNA within and cyclin B-CDK1 complex help in the breakdown of nuclear lamin and initiation of mitosis.

Also, if there is a mutation in Laminin's, wouldn't it restrict any cancer from spreading since those are used by cancers to spread from cell to cell ?

 

[Dr.NickRiviera]

Progeria and Muscular dystrophy...DIT. yup, nuclear lamins are intermediate filaments of nuclear envelope & DNA within and cyclin B-CDK1 complex help in the breakdown of nuclear lamin and initiation of mitosis.

what the heck is progeria?

 

[drj10]

what the heck is progeria?

Progeria is is an extremely rare genetic condition wherein symptoms resembling aspects of aging are manifested at an early age.

In medical school, I remember, I was very fascinated with progeria...we didn't learn in-depths about it though.

Dr. jenkins mentions it in the quiz. Go on wikipedia...there's lot of info on progeria & its ass with lamins mutations.

Ok...back to neuro.

 

[Dr.NickRiviera]

Progeria is is an extremely rare genetic condition wherein symptoms resembling aspects of aging are manifested at an early age.

In medical school, I remember, I was very fascinated with progeria...we didn't learn in-depths about it though.

Dr. jenkins mentions it in the quiz. Go on wikipedia...there's lot of info on progeria & its ass with lamins mutations.

Ok...back to neuro.

just youtubed progeria, pretty cool
one of my favorite music bands "die antwoord" always uses this one strange looking kid in their videos, now i know he has progeria lol