Human cancers arise from an imbalance of cell growth and cell death.Critical factors that control the balance are those regulate the cell cycle.Several molecular effectors have been identified to be able to regulate specific phases of the cell cycle,including cyclins,cyclin-dependent kinases (CDKs) and CDK inhibitors.Notably,deficiency of two G1-checkpoint CDK inhibitors-p21 (CDKN1A) and p27 (CDKN1B)-has been implicated to be correlated with initiation or progression of many human malignancies or cancer cells drug-resistance.However,contradict reports also suggested that p21 and p27 could promote tumor progression.Here,we summarized the historic and recent studies on these two CDK inhibitors,including their identification as well as their roles in carcinogenesis and drug resistance.

Sarcomas collectively represent over 100 different subtypes of bone and soft tissue tumors.They are not sensitive to chemotherapy,which requires the development of tissue-specific or pathway-specific therapies.As our understanding of the molecular mechanisms driving sarcomas is rapidly advancing,the number of targeted therapies is also increasing.Recently identified novel druggable targets including the MDM2 amplifications in welldifferentiated and dedifferentiated liposarcomas,the fusion NAB2:STAT6 of solitary fibrous tumor,the SDH mutations in gastrointestinal stro mal tumors,the suppression of Mcl1 in synovial sarcomas,CDK4 in alveolar rhabdomyosarcoma.They will play an important role in the treatment of sarcoma.Here,the author do an overview of these factors.

With the social development,the number of obese people is increasing.Recent studies have shown that obese women to have breast cancer disease's risk is higher than normal body weight,and etabolic disorders growing threat to human health.Estrogen,aromatase have contributed to the occurrence and development of breast cancer after menopause.AMPK is a negative regulator of aromatase,it can inhibit proliferation of cancer cells by metabolic pathways.What's more metformin,resveratrol inhibited proliferation by this route has been confirmed in breast cancer cells.Here,the author do an overview of the role of obesity-related factor for postmenopausal breast tissue estrogen synthesis and metabolic abnormalities affect aromatase expression in breast.

Versican comes from fibroblasts and belongs to chondroitin sulfate proteoglycan.It distributes in various tissues.The versican have functions including regulate cell growth and differentiation,promote cell proliferation,invasion and metastasis,and stimulate angiogenesis.Experiments have confirmed that the expression of versican is involved in various cancers.Here,the author do an overview of versican in the occurrence and development of breast cancer,liver cancer and chondrosarcoma aimed to further explore the pathogenesis of tumors.