[Application of the improved MTT assay in predicting the intrinsic drug resistance of liver cancer].
OBJECTIVE
To investigate the role of the improved MTT assay in prediction of intrinsic drug resistance of liver cancer.


METHODS
The convenient MTT colorimetry was innovated to test the effects of 4'-epi-adriamycin (E-ADM), carboplatin (CBP), and 5-Fluorouracil(5-Fu), used alone or in combination, on 30 specimens of primary liver cancer without chemotherapy. All of the 30 paraffin-embedded tissues were assembled in a microarray. The used terminal concentrations of drugs were one twentieth those of the plasma peak concentrations calculated by using the liver cancer cells of the line SMMC-7721. The expression of P-glycoprotein (P-gp), multidrug resistant protein (MRP)-3, lung resistance-related protein (LRP), glutathione S-transferase (GST)-pi, and 2 kinds of cyclin-related protein: p16(INK4a) and p21WAF1, were detected by immunohistochemistry.


RESULTS
Sixteen of the 30 specimens (53.3%) were drug-resistant and 14 of the 30 specimens (46.7%) were drug-sensitive. The sequence of drug -sensitivity was in the order of combination chemotherapy, E-ADM, 5-Fu, and CBP. The positive rate of P-gp in the drug-resistant group was 56.3%, significantly higher than that of the drug-sensitive group (14.3%, P < 0.05).


CONCLUSIONS
An improved MTT assay has been developed that is more scientific and worth spreading clinically. Intrinsic drug resistance of liver cancer is popular. P-gp is a good predictive marker in intrinsic drug resistance of liver cancer.
Li
Qian-yu
QY
Department of Pathology, Shanghai Tenth People's Hospital, Shanghai 200072, China.
Wang
Yi
Y
Yin
Zheng-feng
ZF
Wu
Meng-chao
MC
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism; D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000494:pharmacology / Q000627:therapeutic use; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D003124:Colorimetry; D019008:Drug Resistance, Neoplasm; D004354:Drug Screening Assays, Antitumor / Q000379:methods; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008113:Liver Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000970:Antineoplastic Agents