ABSTRACT
Cancer results from mutations that disrupt the harmonious checks and balances that regulate normal cellular growth and development. These mutations arise in two classes of interacting genes:those that facilitate cell growth and tumor formation(oncogenes), in which mutation or overexpression is oncogenic, and those that inhibit these processes(tumor supp-ressor genes) whose loss is oncogenic. The human retinoblastoma(Rb) protein, a tumor suppressor, acts as transcription factor or/and cell cycle regulator. Heterogenous expression of the Rb gene product contributes to the genesis of a diverse group of human neoplasma such as breast, prostate, small cell lu- ng, bladder carcinoma and leukemia. Its structural aberrations were observed in 25% of br- east tumor cell lines studied and 7% of the primary tumors, such as homozygous internal deletions and total deletion. These observations suggest that Rb protein is involved in bre- ast cancer development. Here we report that Rb protein represses steroid receptor function and its involvement of cell cycle process in human breast cancer cell line, MCF7 cells. 1. The overexpression of Rb protein repressed the steroid receptor function in breast cancer cell line, MCF 7. 2. When we introduced the mutant type Rb expression vector(deletion of exon 22), such repression was not observed. 3. By introducing E2F expression vector, the action of Rb protein was repressed. 4. Rb protein modulated the binding patterns of proteins to Kil-GRE site. 5. Flow cytometry analysis showed that Rb protein acts on G0/G1 stage of cell cycle process. These findings provide the molecular basis of breast cancer therapy using Rb protein.
Subject(s)
Humans , Breast Neoplasms , Breast , Cell Cycle , Cell Line , Cell Line, Tumor , Exons , Flow Cytometry , Growth and Development , Leukemia , MCF-7 Cells , Prostate , Receptors, Steroid , Repression, Psychology , Retinoblastoma Protein , Retinoblastoma , Transcription Factors , Urinary BladderABSTRACT
Pregnancy-induced hypertension(PIH) is one of the major causes of maternal, fetal and neonatal morbidity and mortality. Although many causes are encountered, etiology of PIH is still unknown. A molecular variant of angiotensinogen, M235T, reported to be linked with essential hypertension and PIH. This study was to evaluate the molecular variation of angiotensinogen in Korean pregnancy-induced hypertension. Our results did not provide any definite relation with the molecular variant of angiotensinase, M235T, and Korean PIH.
Subject(s)
Female , Pregnancy , Angiotensinogen , Hypertension , Hypertension, Pregnancy-Induced , Mortality , Polymerase Chain ReactionABSTRACT
This article presents the results of the Implementation Study of the Seoul Cancer Registry, which started in July, 1991 as a population based cancer registry in Seoul, Korea. The completeness and validity of the registered data were evaluated using Mortality/Incidence ratio (M/I ratio), Histologically Verified Cases (HV%), Primary Site Uncertain (PSU%), and Age Unknown (Age UNK%). Owing to the additional active surveillance, the completeness of the data turned out to be fairly acceptable, except for the aged over 75(Mortality/Incidence ratio was over 100%). Eventhough the Seoul cancer registry(SCR) has further way to go in the completeness especially among elderly persons, the validity of SCR data was also acceptable in terms of HV%, PSU%, and Age UNK%. However, PSU% and Age UNK% might need to be further reduced to be comparable with other well established cancer registries. The age standardized incidence rates(ASR) of all cancers between July 1, 1991 and June 30, 1992 were 232.4/100,000 in males and 147.9/100,000 in females. The top five major sites of cancers in Seoul were the stomach, liver, lung, colo-rectum, and bladder in order in males, and the uterine cervix, stomach, breast, colo-rectum, and liver in females. Those 5 cancer sites comprised 68.9% and 64.7% of the total cancer incidence in males and females, respectively.
Subject(s)
Adolescent , Adult , Aged , Child , Child, Preschool , Female , Humans , Infant , Male , Age Factors , Incidence , Korea/epidemiology , Middle Aged , Neoplasms/epidemiology , Registries , Sex FactorsABSTRACT
No abstract available.