The safety and treatment response of combination therapy of radioimmunotherapy and radiofrequency ablation for solid tumor: a study in vivo

Targeted radioimmunotherapy with the iodine-131-labeled caerin 1.1 peptide for human anaplastic thyroid cancer in nude mice

OBJECTIVE

The combination of two or more drugs with different mechanisms is a promising strategy for cancer treatment, and radioimmunotherapy (RIT) is a trending antitumor strategy. Radiotherapy (RT) can promote and activate antitumor immune effects, and immunotherapy can strengthen the effects of selective internal radiotherapy (SIRT); the RIT combination is synergistic and can overcome the adverse side effects of monotherapy. In this study, we developed a radioimmunoconjugate (RIC)-the iodine-131 (131I)-labeled caerin 1.1 peptide-to treat human anaplastic thyroid cancer (ATC).

METHODS

Antitumor activity of caerin 1.1 peptide was determined by MTT assay, plate colony formation and cell wound scratch assays, and the mechanism of the inhibition of carein 1.1 peptide on the growth of CAL-62 cells was identified by cell cycle and western blot. Then, we investigated the efficacy of the caerin 1.1 peptide as a single drug and the 131I-labeled caerin 1.1 peptide for ATC. H&E and TUNEL staining was performed to detect dead cells in the tumor tissue sections.

RESULTS

We found that caerin 1.1 arrested cells in the S phase to induce apoptosis and inhibited tumor growth to inhibit phosphorylation of Akt. In vivo, the iodine-131 (131I)-labeled caerin 1.1 peptide achieved better antitumor efficacy than radiotherapy alone and showed a good biosafety profile.

CONCLUSIONS

Our study demonstrates for the first time that the iodine-131 (131I)-labeled caerin 1.1 peptide can inhibit CAL-62 tumor growth and migration. The iodine-131 (131I)-labeled caerin 1.1 peptide, which represents a radioimmunotherapy strategy based on the combination of SIRT with a peptide-drug conjugate, could provide a treatment means for the radical cure of ATC.

Intracranial 131I-chTNT Brachytherapy in Patients with Deep-Seated Glioma: A Single-center Experience with 10-Year Follow-up from China

OBJECTIVE

 The intracranial brachytherapy has been applied for decades, however, no results with long-term follow-up have been reported. This study investigated the long-term efficiency of intra-tumoral injection of ¹³¹I-chTNT in patients with deep-seated glioma.

METHOD

 Thirty-five patients undergoing ¹³¹I-chTNT brachytherapy between December 2004 and May 2009 were enrolled. ¹³¹I-chTNT was injected at a dose of 1.5 mCi/cm³ at an interval of 1 month for consecutive 3 times. Serial ECT scan and MRI were performed during follow-up. Progression-free survival (PFS) and overall survival (OS) were analyzed. Adverse reactions were graded with WHO Toxicity Grading Scale for determining the severity of adverse events.

RESULTS

 ECT scan showed that enhanced accumulation of radioactive agents in the tumor lasted for more than 30 days. Three months after final injection, tumor complete remission (CR) was observed in 4 patients (11.4 %), partial remission (PR) in 11 cases (31.4 %), stable disease (SD) in 10 cases (28.6 %) and progressive disease (PD) in 10 cases (28.6 %). At 6-month, CR, PR, SD and PD were 2, 6, 12 and 15 respectively. After 10 years of follow-up, median progression-free survival (PFS) and overall survival (OS) were 5.4 and 11.4 months. One-year survival was 45.7 %, two and five-year survival was 8.6 %, ten-year survival was 5.7 %. Multivariate analysis showed that pathological grade and tumor diameter were independent prognostic factors for PFS and OS. Grade I-II adverse events occurred after drug injection, including nausea, fever, headache, hairloss and fatigue.

CONCLUSION

 ¹³¹I-chTNT intracranial brachytherapy is efficient and safe for patients with deep-seated glioma. It is a reliable option for inoperable glioma patients.

Effectiveness of combined (131)I-chTNT and radiofrequency ablation therapy in treating advanced hepatocellular carcinoma

To investigate the effectiveness of monoclonal antibody ((131)I-chTNT) and radiofrequency ablation (RFA) combination therapy in treating middle-advanced stage hepatocellular carcinoma (HCC). Thirty-four patients diagnosed with HCC patients, divided into two groups comprised of 22 and 12 cases were included in this retrospective study. The two groups received RFA with or without ((131)I-chTNT) therapy, respectively. The patients in these groups were followed up for a median of 31 and 35 months, respectively. Patient survival was evaluated using Kaplan-Meier method and safety profiles were determined by analyzing liver, thyroid, and bone marrow toxicities. This retrospective study showed that survival time of the patients who received combination therapy was significantly longer than that of the RFA group (P = 0.052). The median progress-free survival of patients in the two groups was 23 and 7 months, respectively, and the difference was significant (P = 0.04). Tumor recurred in 3.5-8.7 months in four of the combination group patients, among which three had newly developed lesions. The red blood cells and platelets counts were not altered on day 7 and 1 month of the treatment, however, number of white blood cells was significantly increased on day 7 which was reversed back to the normal range in 2 weeks. The ALT and AST were also not significantly altered on day 7 and 1 month of therapy. In middle-advanced stage HCC patients, the combination of (131)I-chTNT and RFA therapy was found to be significantly more effective than the RFA treatment alone as assessed in short-term follow-up. However, the dose we used was insufficient to completely block the local recurrence of the lesions with a diameter of 5 cm or larger.