In vivo molecular imaging and radionuclide (131I) therapy of human nasopharyngeal carcinoma cells transfected with a lentivirus expressing sodium iodide symporter

Feasibility of Bone Marrow Mesenchymal Stem Cell-Mediated Synthetic Radiosensitive Promoter-Combined Sodium Iodide Symporter for Radiogenetic Ovarian Cancer Therapy

Ovarian cancer is the most lethal gynecological cancer, most patients relapse within 12-24 months, and eventually die, especially platinum-resistant patients. Gene therapy has been one of the most potential methods for tumor treatment. Bone marrow mesenchymal stem cells (BMSCs) have been used for systemic delivery of therapeutic genes to solid tumors. Sodium iodide symporter (NIS) is an intrinsic membrane glycoprotein and can concentrate ¹³¹I, which is important for radionuclide therapy and nuclear medicine imaging in recent years. However, the rapid iodine efflux has become a bottleneck for NIS-mediated radionuclide gene therapy. Our previous studies found that the early growth response-1 (Egr1) promoter containing CC(A/T)6GG (CArG) elements had an ¹³¹I radiation-positive feedback effect on the NIS gene. Other research showed the synthesized Egr1 promoter containing four CArG elements, E4, was nearly three times as sensitive as the Egr1 promoter. In our study, BMSC-E4-NIS was engineered to express NIS under the control of E4 promoter using lentivirial vectors. After BMSC-E4-NIS implantation, no tumors were seen in BALB/c nude mice and BMSC-E4-NIS did not promote the growth of SKOV3 tumor. BMSCs migrated toward ovarian cancer samples in chemotaxis assays and to ovarian tumors in mice. Using micro-single-photon emission computed tomography/computed tomography (SPECT/CT) imaging, we found that E4 promoter produced a notable increase in ¹²⁵I uptake after ¹³¹I irradiation, the radionuclide uptake is almost three and six times more than Egr1 and cytomegalovirus (CMV) promoters. These studies confirmed the feasibility of using BMSCs as carriers for lentivirus-mediated E4-NIS gene therapy for ovarian cancer. Further research on BMSC-E4-NIS gene therapy for ovarian cancer in vivo will also be carried on, and if successful, this might provide a new adjuvant therapeutical option for platinum-resistant ovarian cancer patients and provide a new method for dynamic evaluation of curative effect.

Bone Marrow-Derived Mesenchymal Stem Cell-Mediated Dual-Gene Therapy for Glioblastoma

Bone-marrow mesenchymal stem cells (BMSCs) have been used for systemic delivery of therapeutic genes to solid tumors. However, the optimal treatment time post-BMSC implantation and the assessment of the long-term fate of therapeutic BMSCs post-tumor treatment are critical if such promising therapies are to be translated into clinical practice. An efficient BMSC-based therapeutic strategy has been developed that simultaneously allows killing of tumor cells, inhibiting of tumor angiogenesis, and assessment and eradication of implanted BMSCs after treatment of glioblastoma. BMSCs were engineered to co-express the angiogenesis inhibitor kringle 5 (K5) of human plasminogen, under the control of the cytomegalovirus promoter (CMV) and the human sodium-iodide symporter (NIS), involved in uptake of radioisotopes, under the control of early growth response factor 1 (Egr1), a radiation-activated promoter. A significant decrease in tumor growth and tumor angiogenesis and a subsequent increase in survival were observed when mice bearing glioblastoma were treated with ¹⁸⁸Re post-therapeutic intravenous BMSC implantation. Furthermore, the systemic administration of ¹⁸⁸Re post-tumor treatment selectively eliminated therapeutic BMSCs expressing NIS, which was monitored in real time by ¹²⁵I micro single photon emission computed tomography/computed tomography imaging. Meanwhile, the Egr1 promoter induced a ¹⁸⁸Re radiation positive feedback effect absorbed by NIS. After intravenous BMSC implantation, BMSCs levels in the tumor and lung both peaked on day 10 and decreased to the lowest levels on days 24 and 17, respectively. These findings suggest that day 17 post-BMSC implantation could be an optimal time for ¹⁸⁸Re treatment. These results provide a new adjuvant therapy mediated by BMSCs for glioblastoma treatment.

Use of rhenium-188 for in vivo imaging and treatment of human cervical cancer cells transfected with lentivirus expressing sodium iodide symporter

Although survival rates for cervical cancer have improved, they need further improvement in patients with distant metastases. The sodium iodine symporter (NIS) gene has often been used in cancer therapy and imaging. We examined the therapeutic effects of rhenium-188 (188Re) in a cervical cancer xenograft model expressing the NIS gene under the control of the tumor-specific human telomerase reverse transcriptase (hTERT) promoter. We constructed two recombinant lentiviral vectors expressing enhanced green fluorescent protein (eGFP) or the NIS gene driven by the hTERT promoter. To determine the tumor-specific transcriptional activity of the hTERT promoter, the eGFP-expressing vector was stably transfected into tumor cells and normal cells. A cervical cancer HeLa cell line stably expressing NIS (HeLa-TERTNIS) was created and examined in a similar way. HeLa and HeLa-TERTNIS tumor xenografts were transplanted in nude mice, and in vivo 188Re distribution was measured using micro-SPECT/CT imaging. The therapeutic effects of 188Re were assessed over 21 days on the basis of tumor volume and the immunohistochemical findings of excised tumors. eGFP expression controlled by the hTERT promoter was substantially higher in the tumor cells than normal cells. Quantitative PCR and western blotting confirmed that HeLa-TERTNIS cells expressed high levels of NIS mRNA and protein, respectively. Further, 188Re uptake and accumulation were significantly higher in HeLa-TERTNIS cells and xenografts than HeLa cells and xenografts. In vitro and in vivo, 188Re significantly reduced the survival of HeLa-TERTNIS cells and inhibited the growth of HeLa-TERTNIS xenografts, respectively. Immunohistochemical staining showed that HeLa-TERTNIS xenograft tumors expressed higher levels of NIS and caspase-3 and lower levels of Ki-67 than HeLa xenograft tumors. Our findings indicated that hTERT promoter-driven expression of the NIS gene in HeLa cells led to 188Re uptake and therapeutic effects. Thus, NIS-based gene therapy and imaging using the hTERT promoter and 188Re may be possible.

Protective Effects of Royal Jelly on Oxymetholone-Induced Liver Injury in Mice

Background:

The present study was carried out to investigate the possible protective effects of royal jelly (RJ) on oxymetholone (OXM)-induced oxidative liver injuries in mice.

Methods:

In total, 32 adult male NMRI mice were divided into four groups of eight mice each. Mice in groups 1 and 2 were orally administered 5 mg/kg/day OXM for 30 days. At the same time, mice in group 3 received RJ at a dose of 100 mg/kg/day. Saline control and RJ control groups were also included in this study.

Results:

Administration of 5 mg/kg OXM resulted in a significant decrease in total antioxidant capacity and catalase activity, as well as a significant increase in malondialdehyde (P<0.05). In addition, OXM-administrated mice showed a slight increase in liver enzymes, including alanine amino transferase, aspartate amino transferase, and alkaline phosphatase. Although OXM caused histopathological changes in the liver, RJ could significantly improve all of the above-mentioned parameters at a dose of 100 mg/kg.

Conclusion:

The results of the present study indicated that RJ has a partially protective effect on OXM-induced liver toxicity in mice.

Chlorotoxin-Conjugated Multifunctional Dendrimers Labeled with Radionuclide 131I for Single Photon Emission Computed Tomography Imaging and Radiotherapy of Gliomas

Chlorotoxin-conjugated multifunctional dendrimers labeled with radionuclide 131I were synthesized and utilized for targeted single photon emission computed tomography (SPECT) imaging and radiotherapy of cancer. In this study, generation five amine-terminated poly(amidoamine) dendrimers were used as a platform to be sequentially conjugated with polyethylene glycol (PEG), targeting agent chlorotoxin (CTX), and 3-(4'-hydroxyphenyl)propionic acid-OSu (HPAO). This was followed by acetylation of the remaining dendrimer terminal amines and radiolabeling with 131I to form the targeted theranostic dendrimeric nanoplatform. We show that the dendrimer platform possessing approximately 7.7 CTX and 21.1 HPAO moieties on each dendrimer displays excellent cytocompatibility in a given concentration range (0-20 μM) and can specifically target cancer cells overexpressing matrix metallopeptidase 2 (MMP2) due to the attached CTX. With the attached HPAO moiety having the phenol group, the dendrimer platform can be effectively labeled with radioactive 131I with good stability and high radiochemical purity. Importantly, the 131I labeling renders the dendrimer platform with an ability to be used for targeted SPECT imaging and radiotherapy of an MMP2-overexpressing glioma model in vivo. The developed radiolabeled multifunctional dendrimeric nanoplatform may hold great promise to be used for targeted theranostics of human gliomas.