Cell cycle

CELL CYCLE-

Cancer cell depends on AEROBIC GLYCOLYSIS for growth

Serine/threonine Akt oncogene stomulates glycolysis in malignant cells

Most variable phase- G1

DNA doubling- S phase

CELL doubling- mitotic phase

Most critical phase? G1👉S

CYCLINS

Sequence of cyclins appears D👉E👉
A👉B

First cyclin to appear in cell cycle CYCLIN D( mid G0 phase)

Cyclin E appearances in which phase-  late G1

Cyclin A in which phase? Mid S phase

Cyclin B in which phase? M phase

Which cyclin involves in G1/S transition? E

Whivh cyclin involved in G2/M transition? A

Which cyclin initiates mitosis? B

CELL CYCLE INHIBITORS

💁cip/kip family? P21 p27 p57

💁INK 4a/ARF family? P16ink 4a and p14 Arf

DRUGS ACTING ON CELL CYCLE

Vinblastine- G1

Mtx,mitomycin c,Doxorubicin,Cytarabine,Hydroxy urea,5-FU- S PHASE

Daunorubicin,Bleomycin,Etoposide,Topotecan-G2 phase

💁Vincristine,Paclitaxel-M phase

CHECK POINTS

💁two check points of cell cycle- G1S TRANSITION  and  G2M transition

💁chromosomal abnormalities occurs in cells irradiated in which phase- G1 phase

💁chromatid abberation occurs in cells irradiated in G2 PHASE

RADIO AND CHEMOSENSITIVE

💁most radio sensitive phase? M> G2M

💁Most radio resistant phase? End of S phase

💁most chemosensitive? S phase

💁 Most Radiosensitive Tissue – Bone Marrow

💁 Least Radiosensitive Tissue – Nervous Tissue

💁Most Radiosensitive blood cell – Lymphocyte

💁Least Radiosensitive blood cell – Platelet

💁Most Radiosensitive organ – Skin

💁Least Radiosensitive organ – Vagina

💁Most Radiosensitive mucosa – Interstitial Mucosa

💁most radiosensitive layer of retina-rods and cones

most radioresistant layer of retina-ganglion layer

Cell cycle specific -
G1  S topoisomerase - 2
 S antimetabolite
 G2 M topoisomerase 2 and bleomycin
 M  vinca alkaloids
Taxanes , estrogen

Cell cycle non specific
 topoisomerase 1 inhibitors
 alkylating agents
 All anti ca antibiotics except bleomycin
 platinum group