Search

Purpose: HAb18G/CD147 is a hepatocellular carcinoma (HCC)-associated antigen. We developed iodine ( 131 I) metuximab injection (Licartin), a novel 131 I-labeled HAb18G/CD147-specific monoclonal antibody F(ab') 2 fragment, and evaluated its safety, pharmacokinetics, and clinical efficacy on HCC in Phase I/II trials. Methods and Materials: In a Phase I trial, 28 patients were randomly assigned to receive the injection in 9.25-, 18.5-, 27.75-, or 37-MBq/kg doses by hepatic artery infusion. In a multicenter Phase II trial, 106 patients received the injection (27.75 MBq/kg) on Day 1 of a 28-day cycle. Response rate and survival rate were the endpoints. Results: No life-threatening toxic effects were found. The safe dosage was 27.75 MBq/kg. The blood clearance fitted a biphasic model, and its half-life was 90.56–63.93 h. In the Phase II trial, the injection was found to be targeted and concentrated to tumor tissues. Of the 73 patients completing two cycles, 6 (8.22%) had a partial response, 14 (19.18%) minor response, and 43 (58.90%) stable disease. The 21-month survival rate was 44.54%. The survival rate of progression-free patients was significantly higher than that of patients with progressive disease after either one or two cycles ( p p = 0.0019). Conclusion: Iodine ( 131 I) metuximab injection is safe and active for HCC patients.

Radioimmunotherapy may improve the outcome of hepatocellular carcinoma (HCC) patients by delivering targeted radiation to liver lesion tissue while relatively sparing nontarget tissues. This study was designed to observe the biodistribution, localization and imaging characteristics of 131I -labeled Metuximab in 24 patients with HCC to determine the diagnostic and therapeutic potential of this antibody.Twenty-four HCC patients were randomly divided into three groups to receive 18.5, 27.75 and 37 MBq/kg of 131I-labeled Metuximab per kilogram of body weight, respectively. 99mTc-sodium phytate was administered intravenously and the single photon emission computed tomography (SPECT) scanning was performed. After 48 h, 131I -labeled Metuximab was injected by hepatic artery intubation, and SPECT scan performed at 7 d. The percentage of absorbed 131I (%ID) and the time-dependent 131I tumor:nontumor tissue (T/NT) ratios were calculated at 12, 48, 96 and 192 h after injection.The positive Imaging result of MAb scanning in 24 patients showed that the iodine 131 conjugated to Metuximab was apparently accumulated more in hepatoma. Biodistribution studies of 131I-Metuximab in trial I demonstrated that the comparable % ID uptake in tumor (with a T/NT ratio at 12, 48, 96 and 192 h) to that in such normal organs, as thyroid, heart, lung, spleen and intestines were all more than one. The optimal imaging time for the highest T/NT ratio in liver was at 192 h.131I-labeled Metuximab could deliver relatively selective radiation to tumor tissues and may have potential efficacy in relieving hepatocellular carcinoma.

A 15-mer phosphorothioate antisense oligonuclide (ASON) complementary to the translation start region of the C-myc oncogene mRNA was radioiodinated to enhance its antitumor activity, and vasoactive intestinal peptide bound covalently polylysine (VIP-polylysine) was used as a carrier to deliver the oligonucleotide into VIP receptor-positive tumor cells. The antitumor activity of radioiodinated ASON conjugated to VIP-polylysine(VIP-131I-ASON) was investigated in athymic mice bearing HT29 tumor xenografts in comparison with unconjugated radioiodinated ASON(131I-ASON), unlabelled ASON (VIP-ASON) and scrambled oligonucleotide (VIP-131I-MON) conjugated to VIP-polylysine. Conjugation 125I-ASON to VIP-polylysine resulted in a 5.6-fold decrease in the plasma clearance and a 3.4-fold increase in tumor uptake of the radiopharmaceutical. Athymic mice bearing HT29 tumor xenografts were treated with 4 weekly doses of VIP-131I-ASON and the antitumor effects were assessed by use of the slope of the tumor growth curve. VIP-131I-ASON exhibited strong antitumor effects against HT29 xenografts, decreasing tumor growth rate 9.67-, 7.90-fold more effectively than 131I-ASON and VIP-ASON at equivalent doses of ASON. Conversely, 131I-ASON, VIP-ASON or VIP-131I-MON caused no significant effect compared with the normal saline. These data indicated that use of a VIP-polylysine carrier greatly increased HT29 tumor uptake of ASON and treatment with the VIP-131I-ASON complexes resulted in tumor growth delay in human colon cancer xenograft.

To study pharmacokinetics of injection of iodine-131 labelling MEI-TUO-XI monoclonal antibody (hepatoma monoclonal antibody HAb18 F(ab')2) in vivo. 24 cases of primary hepatocelluar carcinoma (PHC) were equally divided into the low dose group, middle dose group and high dose group. After the relevant injection was administrated into the hepatic artery of each case, intravenous blood and urine samples were separately collected at different time for determination of the radioactive count ratio (min(-1)). The proportion of 131I-HAb18 F(ab')2 in serum of each blood sample was determined, and the radioactive count ratio (min(-1)) of druggery for each blood sample was revised according to the proportion. The pharmacokinetic parameters were calculated using DAS ver 1.0 (Drug And Statistics for Windows) program. The component of urine radiomaterial was determined and the percentages of urine radioactivity in administration dosage were calculated. The catabolism of the injection with time accorded with dynamics two-compartment model. The catabolism product was mainly free-131I and was excreted via kidney; the urine radioactivity was 47.70%-51.16% of administration dosage during 120 h after administration of drug. Therefore, the pharmacokinetics of the injection can satisfy the clinical demands. The drug dose recommended for clinical use was 27.75 MBq of the injection for each kg of human body.

A 15-mer phosphorothioate antisense oligonucleotide (ASON) complementary to the translation start region of the C-myc oncogene mRNA was labeled with 131I or 125I and the labelled compound was linked to the vasoactive intestinal peptide (VIP) to be bound covalently to a polylysine chain so as to deliver oligonucleotide into tumor cells. The effect of the VIP as carrier on cell uptake of ASON in tissue culture was evaluated in a human colon adenocarcinoma HT29 cell line. The efficacy of VIP-131-ASON on cell growth was evaluated using the MTT assay. Expression of c-myc-encoded protein was measured by flow cytometry. Sense and nosense control Oligonucleotides with VIP carrier were used as control. The results showed that VIP competed effectively with VIP-125I-ASON to bind the HT29 cells. Cell uptake was increased 3-4 fold using the VIP carrier compared to the same dosage of naked DNA. HT29 cells treated with VIP-131I-ASON complexes exhibited 4-fold lower proliferation than those treated with 13I-ASON and 6-fold lower proliferation than those treated with radioiodinated Sense and nosense DNA. Cancer protein expression of HT29 cells treated with VIP-131I-ASON was decreased 2-fold compare with that in 131I-ASON treated cell. The use of a VIP carrier greatly increased 131I-ASON cellular uptake and inhibition of cell proliferation and C-myc cancer protein expressing in HT29 cell by radioiodinated antisense Oligonucleotides.

The radiobiological effect of 131I radiolabeled recombinant human epidermal growth factor (131I-rhEGF) on nude mice with human breast cancer was assessed in this study. The tissue mainly uptaking 131I-rhEGF was found by tissue distribution assay in mice. The radiation breakdown of the tissue greatly collecting 131I-rhEGF was examined by biochemical test and biopsy in nude mice with human breast cancer. The tissue distribution assay of 131I-rhEGF in mice showed that 131I-rhEGF greatly accumulated in kidney, liver, spleen and blood. The biochemical test and biopsy revealed that 131I -rhEGF injected twice (dosing once is analogous to 14.58 GBq in a person with 50 kg, once every 14 days) had an effective killing effect on tumor but had no effect of radiation breakdown on kidney, liver,spleen and blood-cell forming tissue in mice with human breast cancer. Therefore, 131I-rhEGF is a drug unharmful to normal tissues in the course of the receptor-mediated target radiotherapy for breast cancer.

This experiment was designed to study the effect of 131I-recombinant human epidermal growth factor (131I-rhEGF) on the growth of tumor in nude mice loaded with human breast cancer. Bioactivity of 131I-rhEGF and uptake of 131I-rhEGF in breast cancer tissue were verified using biodistribution experiment of 131I-rhEGF in the nude mice loaded with human breast cancer. The effect of 131I-rhEGF on the growth of tumor was assessed via the growth experiment of tumor in the nude mice loaded with human breast cancer. The ultrastructural change of the tumor cell treated with 131I-rhEGF was observed under transmission electron microscope, and the pathological change of the tumor tissue treated with 131I-rhEGF was detected by biopsy. The results showed that the tumor tissue of nude mice bearing human breast cancer obviously takes in 131I-rhEGF; that intravenous administration and intratumoral administration of 131I-rhEGF both obviously inhibit the growth of tumor, the inhibition rates (82.00% and 80.70%) being remarkably higher than that of 131I (7.49%) and that of 131I-HSA (6.91%) (P0.05); and that intravenous and intratumoral administration of 131I-rhEGF both obviously damage and kill tumor cells. Therefore, 131I-rhEGF can inhibit the growth of human breast cancer cell in nude mice; it is a potential receptor-mediated radioactivity targeting drug for treating breast cancer.