Human Hepatoma SMMC-7721 Cells Research Articles

Characterization of a novel monoclonal antibody raised against human hepatocellular carcinoma.

A monoclonal antibody (MAb) targeting human hepatocellular carcinoma (HCC) has been produced by immunizing BALC/c mice with HCC SMMC-7721 cells. Solid phase enzyme-linked immunoabsorbent assay (ELISA) analysis showed that this mAb (mAb 95) was reactive with human HCC cell lines and tumor biopsies, but not tumors of other origin or normal tissues tested. Immuno-gold labeling and flow cytometry indicated that mAb 95 bound specifically to HCC cell membrane protein. Western blot analysis showed mAb 95 reacts only with HCC cell lysates, but not with 10 different human normal tissue lysates. The approximate molecular size of the reactive proteins were 40,000 and 60,000 daltons. The specificity of mAb 95 indicates it may be a potential candidate for a targeting agent in HCC immunotherapy or immunodetection.

Transcriptional regulation of human transcription factor IIB in SMMC-7721 human hepatocellular carcinoma cells by all- trans -retinoic acid and phorbol 12-myristate 13-acetate

The differential-display reverse transcription/polymerase chain reaction (DDRT-PCR) method was utilised to find genes differentially expressed at the messenger RNA level in SMMC-7721 human hepatocellular carcinoma cells treated and not treated with all-trans-retinoic acid, a differentiation inducer of the cell. Human transcription factor IIB (TFIIB) was discovered to be decreased on the 3rd day after the cells had been treated with retinoic acid and increased by phorbol 12-myristate 13-acetate, which stimulated the proliferation of human hepatocellular carcinoma cells. It was also found that the transcription of TFIIB in SMMC-7721 cell had no relationship to the cell cycle.

Serum deprivation enhances DNA synthesis of human hepatoma SMMC7721 cells.

AIM:To determine the relationship between serum deprivation or serum levels and cell proliferation of human hepatoma SMMC-7721 cells.METHODS:Human hepatoma SMMC-7721 cells were grown in RPMI 1640 supplemented with 10% fetal calf serum (FCS)in 5% CO(2) incubator at 37&mgr; for 24h, and culture media were replaced to serum-free or different serum FCS levels (2.5%, 5%, 10%, 20% and 25%). Six h,12h,18h and 24h after the culture,the cells were incorporated &mgr;(3)H&mgr;-TdR for 4h. At last &mgr;(3)H&mgr;-TdR incorpor-ation was detected with liquid scintillation counting.RESULTS:DNA synthesis of SMMC-7721 cells could be sharply stimulated by short-time (6h) serum deprivation (the cpm value of (3)H-TdR incorporation of cells in serum-free was 39.32-fold higher than cells in 25% serum),and the incorporation of (3)H-TdR was negatively related to the serum levels.Longer-time serum starvation (12h, 18h and 24h) also greatly stimulated DNA synthesis, although the cpm value of (3)H-TdR incroporation was less than that in 6h serum deprivation. Morphology of cells cultured in different serum levels also showed significant difference.CONCLUSION:Compared with other cell lines such as BEL7404 and Swiss 3T3,human hepatoma SMMC-7721 cells had different response to the serum deprivation.Short-time serum deprivation could greatly stimulate DNA synthesis of human hepatoma SMMC-7721 cells.Precautions must be given to the changes of serum levels for the detection of growth factors and drugs using SMMC-7721 cells as a model.

Biological effects of hepatoma cells irradiated by 25MeV/u(40)Ar(14+).

Radiotherapy was initiated when Grubbe treated tumor with X-rays in 1896[1]. Afterwards, radioisotopes such as Ra and Rn, were used for clinical diagnosis and treatment. Basic researches on the biological effects of X-rays, γ-rays, fast neutron, and so on discovered that damages to mammalian cells induced by high-LET irradiation were more serious than that by low-LET[2]. Because of their low oxygen enhancement ratio (OER) and high relative biological effectiveness (RBE), heavy ions can kill carcinoma cells efficiently[3], among which about 5%-20% was hypoxia. There was a Bragg peak along the energy deposition of heavy ions, so that more dose could reach to the tumor while less to the normal tissues[4]. Therefore, heavy ion beam is believed to play an important role in the future in the radiotherapy for tumors. The treatment with heavy ion beam has been studied and put into clinical practice since the 1970s in America and since 1994 in Japan. But in our country, this research is still in its initial stage. This is our preliminary report on the dose--response and fractionated irradiation with 25MeV/u 40Ar14+ in human hepatoma SMMC-7721 cells.

Survival and malignant phenotype changes of human hepatoma SMMC-7721 cell line induced by cryopreservation at -50 °C.

To investigate the effect of cryopreservation at -50 °C on the human hepatoma SMMC-7721 cell line. With 15% DMSO as a cryoprotectant, the SMMC-7721 cells were cryopreserved at -50 °C, then thawed and recultured. The survival rate, mitotic index and LDH isoenzymes were compared between pre- and post-cryopreservation. Thirteen hours after the thaw, the mitotic index of cryopreserved SMMC-7721 cells decreased by 1.09%. The mode scope of chromosome number (46-53) after cryopreservation tended to transfer to that of normal human cells, and the percentage of metaphases containing 46 chromosomes changed from 0% to 16%. LDH isoenzymes changed from H-like model (LDH3(29.3%) > LDH4 (26.8%) > LDH2 (25.3%) > LDH5 (14.9%) > LDH1 (3.6%) to M-like model (LDH4 (48.3%) > LDH5 (28.3%) > LDH3 (18.9%) > LDH2 (4.4%) > LDH1 (0%)). This suggests that the survival rate could reach over 95%. Cryopreservation at -50 °C can be a convenient method for the cryopreservation of cell lines. However, cryopreservation at -50 °C is likely involved in the changes of the malignant phenotypes of the human hepatoma SMMC-7721 cell line, and may induce the differentiation of malignant cells.

Survival and malignant phenotype changes of human hepatoma SMMC-7721 cell line induced by cryopreservation at -50 °C

Survival and malignant phenotype changes of human hepatoma SMMC-7721 cell line induced by cryopreservation at -50 °C

Effects of TNF in bacterial infections

Berberine and evodiamine, two kinds of alkaloids, have been reported to show many activities. In the present paper, inhibitory activities of the two compounds and their mixtures on human hepatocellular carcinoma SMMC-7721 cells were investigated, and the inhibitory rates, apoptosis, cell cycle distribution and tumor necrosis factor-α (TNF-α) were all tested and described. The results indicate that the mixtures of the two compounds showed the highest inhibition effect (50.00%) as compared with berberine and evodiamine used individually (20.24% and 16.33%, respectively) over 48 h. Through fluorescence microscope and flow cytometry (FCM) analysis, the cell apoptosis and cell cycle distribution of SMMC-7721 induced by the synergy of the two compounds was made evident. Furthermore, the TNF-α value in the mixture treated group was much higher (p<0.05) than in the other two groups. Thus, the combined use of berberine and evodiamine could significantly enhance the apoptosis of SMMC-7721 cells, which will be useful to further anti-cancer therapy and research.