Reducible Poly(Oligo-D-Arginine) as an Efficient Carrier of the Thymidine Kinase Gene in the Intracranial Glioblastoma Animal Model

Gene therapy has been considered as an alternative treatment for glioblastoma therapy. In this study, a glioblastoma-specific suicide gene, pEpo-NI2-SV-TK, was delivered into the intracranial glioblastoma model using reducible poly(oligo-d-arginines) (rPOA). pEpo-NI2-SV-TK has the erythropoietin (Epo) enhancer and the nestin intron 2 (NI2) for glioblastoma specific gene expression. The in vitro studies showed that the rPOA formed stable complexes with pEpo-NI2-SV-TK. In the MTT and TUNEL assays, rPOA showed lower cytotoxicity than polyethylenimine (25 kDa, PEI25k). In addition, the rPOA/pEpo-NI2-SV-TK complex induced higher glioblastoma cell death under hypoxic condition than normoxic condition, suggesting that pEpo-NI2-SV-TK induced gene expression in the hypoxic tumor tissue. For in vivo therapeutic efficacy evaluation, the rPOA/pEpo-NI2-SV-TK complex was injected into the brains of an intracranial glioblastoma rat model. The rPOA/pEpo-NI2-SV-TK injected group had a significantly reduced tumor size, compared with the control and the PEI25k/pEpo-NI2-SV-TK injected group. The TUNEL assay showed that the rPOA-pEpo-NI2-SV-TK complex had more apoptotic cells than the control and PEI25k/pEpo-NI2-SV-TK injected groups. These results suggest that the rPOA is an efficient carrier for pEpo-NI2-SV-TK and increased the therapeutic efficacy in the intracranial glioblastoma models. Therefore, the rPOA/pEpo-NI2-SV-TK complex may be useful for glioblastoma specific gene therapy.

Measuring absorbed dose for i-CAT CBCT examinations in child, adolescent and adult phantoms

OBJECTIVES

Design and construct child and adolescent head phantoms to measure the absorbed doses imparted during dental CBCT and compare with the absorbed dose measured in an adult phantom.

METHODS

A child phantom was developed to represent the smallest patients receiving CBCT, usually for craniofacial developmental concerns, and an adolescent phantom was developed to represent healthy orthodontic patients. Absorbed doses were measured using a thimble ionization chamber for the custom-built child and adolescent phantoms and compared with measurements using a commercially available adult phantom. Imaging was performed with an i-CAT Next Generation (Imaging Sciences International, Hatfield, PA) CBCT using two different fields of view covering the craniofacial complex (130 mm high) or maxilla/mandible (60 mm high).

RESULTS

Measured absorbed doses varied depending on the location of the ionization chamber within the phantoms. For CBCT images obtained using the same protocol for all phantoms, the highest absorbed dose was measured in all locations of the small child phantom. The lowest absorbed dose was measured in the adult phantom.

CONCLUSIONS

Images were obtained with the same protocol for the adult, adolescent and child phantoms. A consistent trend was observed with the highest absorbed dose being measured in the smallest phantom (child), while the lowest absorbed dose was measured in the largest phantom (adult). This study demonstrates the importance of child-sizing the dose by using dedicated paediatric protocols optimized for the imaging task, which is critical as children are more sensitive to harmful effects of radiation and have a longer life-span post-irradiation for radiation-induced symptoms to develop than do adults.

Peptide micelle-mediated delivery of tissue-specific suicide gene and combined therapy with avastin in a glioblastoma model

Bevacizumab (Avastin) is an angiogenesis inhibitor used as a treatment for various cancers. In this study, the combination therapy of Avastin and glioblastoma-specific thymidine kinase gene [pEpo-NI2-SV-herpes simplex virus thymidine kinase(HSVtk)] was evaluated in a glioblastoma animal model. The R7L10 peptide was used as a gene carrier of pEpo-NI2-SV-HSVtk. Gel retardation assays confirmed that R7L10 formed stable complexes with pEpo-NI2-SV-HSVtk. R7L10 protected DNA from nuclease digestion. R7L10 had lower transfection efficiency than polyethylenimine (PEI; 25 kDa). However, the in vitro and in vivo toxicity assays showed that R7L10 had lower cytotoxicity than PEI, suggesting that R7L10 is safer than PEI. For the combination therapy, Avastin was injected intravenously and the pEpo-NI2-SV-HSVtk/R7L10 complexes were injected intratumorally in the glioblastoma animal model. Tumor growth was most effectively inhibited by the combination therapy of Avastin and the gene. The immunostaining results confirmed that the HSVtk genes were expressed in the groups with the pEpo-NI2-SV-HSVtk/R7L10 complex. The terminal deoxynucleotidyl transferase dUTP nick end labeling assay showed a higher level of apoptotic cells in the combination group than the pEpo-NI2-SV-HSVtk/R7L10 complex or Avastin group. In conclusion, the combination of Avastin and the glioblastoma-specific HSVtk gene has a higher antitumor effect than single therapy of Avastin or HSVtk after intratumoral administration in glioblastoma animal model.

Diffuse Large B-Cell Lymphoma with Involvement of the Breast and Testis in a Male Patient

Here we report a case of a 76-year-old man with diffuse large B-cell lymphoma (DLBCL) with simultaneous involvement of the right breast and left testicle. The patient underwent complete resection of the involved testis, followed by immunochemotherapy with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP) and prophylactic radiotherapy to the contralateral testis. Following this multimodal therapy, he achieved a complete response. This is a rare case of DLBCL involving both the breast and the testis in a male patient.

Improved biomass and lipid production in a mixotrophic culture of Chlorella sp. KR-1 with addition of coal-fired flue-gas

Industrial CO2-rich flue-gases, owing to their eco-toxicity, have yet to be practically exploited for microalgal biomass and lipid production. In this study, various autotrophic and mixotrophic culture modes for an oleaginous microalga, Chlorella sp. KR-1 were compared for the use in actual coal-fired flue-gas. Among the mixotrophic conditions tested, the fed-batch feedings of glucose and the supply of air in dark cycles showed the highest biomass (561 mg/L d) and fatty-acid methyl-ester (168 mg/L d) productivities. This growth condition also resulted in the maximal population of microalgae and the minimal population and types of KR-1-associated-bacterial species as confirmed by particle-volume-distribution and denaturing-gradient-gel-electrophoresis (DGGE) analyses. Furthermore, microalgal lipid produced was assessed, based on its fatty acid profile, to meet key biodiesel standards such as saponification, iodine, and cetane numbers.

Abstract P6-06-25: Usefulness of pretreatment NLR as prognostic factor of late recurrence, 5-year after primary treatment

Background

Prognostic factor and predictive factors are well established in early-stage breast cancer, but less is known about recurrence, especially 5-year after primary treatment. While mortality of breast cancer is from organic dysfunction with metastatic disease, not from the diseased breast itself, still we do not have adequate information about metastatic disease as we do about primary breast cancer itself.

The aim of this study is to investigate of usefulness of pretreatment NLR(neutrophil to lymphocyte ratio) as prognostic factor that can tell risk of recurrence 5- year after primary treatment.

Patients and methods

A retrospective review of invasive breast cancer patients surgically resected between January 2001 and December 2007. Exclusion criteria were as followings: patients with recurrence or death within 5yrs.

Results

A total of 301 patients were included and 13 patients experienced with recurrence after 5 years.

Table 1. Patients' characteristics Total (n = 301) N (%)Age*48.8(±11.4)Age ≤3525(8.3)35< ≤50165(54.8)50<111(36.9)Histology Ductal270(89.7)Lobular7(2.3)Others24(8.0)Tumor size (cm)*2.73(±1.64)T stage T1126(41.9)T2158(52.5)T317(5.6)N stage N0199(66.1)N167(22.3)N220(6.6)N311(3.7)unknown4(1.3)Histologic grade I72(23.9)II110(36.5)III70 (23.3)unknown49(16.3)Estrogen receptor Negative111(36.9)Positive185(61.5)unknown5(1.6)Progesterone receptor Negative129(42.9)Positive167(55.5)Unknown5(1.6)HER-2 Negative196(65.1)Positive98(32.6)unknown7(2.3)Molecular subtype Luminal A136(45.2)Luminal B66(21.9)HER-2 enriched32(10.6)Triple negative60(20.0)unknown7(2.3)Late recur Yes13(4.3)No288(95.7)*mean±SD

Overall average of NLR value was 2.16, median value was 1.83. The average NLR were 2.80±1.68 in patients with recurrences occurred after 5 years and 2.13±1.15 in patients without recurrence. The NLR cutoff value of 1.83 was determined by median value.

In 1.83≤NLR group has a higher incidence of recurrence after 5 years compared with NLR<1.83 group (8yr DFS 99.2% vs. 93.3%, p = 0.021). Especially in luminal A(ER (+) or PR (+), HER-2(-)), 1.83≤NLR group has a higher incidence of recurrence after 5 years compared with NLR<1.83 group (8yr DFS 100% vs. 87.0%, p = 0.015).

Conclusion

We found that pretreatment NLR is associated with late recurrence that occurs after five years. And we suggest that NLR could be used as one of the prognostic factor that can tell about late recurrence, 5-year after primary treatment.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-06-25.

PTRF/cavin-1 neutralizes non-caveolar caveolin-1 microdomains in prostate cancer

Caveolin-1 has a complex role in prostate cancer and has been suggested to be a potential biomarker and therapeutic target. As mature caveolin-1 resides in caveolae, invaginated lipid raft domains at the plasma membrane, caveolae have been suggested as a tumor-promoting signaling platform in prostate cancer. However, caveola formation requires both caveolin-1 and cavin-1 (also known as PTRF; polymerase I and transcript release factor). Here, we examined the expression of cavin-1 in prostate epithelia and stroma using tissue microarray including normal, non-malignant and malignant prostate tissues. We found that caveolin-1 was induced without the presence of cavin-1 in advanced prostate carcinoma, an expression pattern mirrored in the PC-3 cell line. In contrast, normal prostate epithelia expressed neither caveolin-1 nor cavin-1, while prostate stroma highly expressed both caveolin-1 and cavin-1. Utilizing PC-3 cells as a suitable model for caveolin-1-positive advanced prostate cancer, we found that cavin-1 expression in PC-3 cells inhibits anchorage-independent growth, and reduces in vivo tumor growth and metastasis in an orthotopic prostate cancer xenograft mouse model. The expression of α-smooth muscle actin in stroma along with interleukin-6 (IL-6) in cancer cells was also decreased in tumors of mice bearing PC-3-cavin-1 tumor cells. To determine whether cavin-1 acts by neutralizing caveolin-1, we expressed cavin-1 in caveolin-1-negative prostate cancer LNCaP and 22Rv1 cells. Caveolin-1 but not cavin-1 expression increased anchorage-independent growth in LNCaP and 22Rv1 cells. Cavin-1 co-expression reversed caveolin-1 effects in caveolin-1-positive LNCaP cells. Taken together, these results suggest that caveolin-1 in advanced prostate cancer is present outside of caveolae, because of the lack of cavin-1 expression. Cavin-1 expression attenuates the effects of non-caveolar caveolin-1 microdomains partly via reduced IL-6 microenvironmental function. With circulating caveolin-1 as a potential biomarker for advanced prostate cancer, identification of the molecular pathways affected by cavin-1 could provide novel therapeutic targets.

Molecular characterization and an infectious clone construction of sweet potato leaf curl virus (SPLCV) isolated from Korea

Sweet potato leaf curl disease (SPLCD) was primarily identified in sweet potato fields in Korea in 2003, and the complete genomic sequence of sweet potato leaf curl virus (SPLCV) has been cloned. The genome of the Korean SPLCV isolate (SPLCV-KR) comprises 2,828 nucleotides with six open reading frames in DNA-A, similar to a monopartite begomovirus. Additionally, neither the genome B genomic component nor the DNA beta sequence was detected. The results of phylogenetic analysis using the maximum parsimony method showed that SPLCV-KR is more closely related to SPLCV-US (US) than SPLCV-CN (China) and SPLCV-JP (Japan). A tandem repeat dimer of SPLCV-KR was cloned and found to be infectious in sweet potatoes (Ipomoea batatas) via biolistic inoculation. The SPLCV-infected sweet potatoes exhibited mild leaf curl symptoms of SPLCD, and the newly-replicated viral DNA was detected via Southern blot analysis. Results of biotic, molecular, and phylogenetic characterization suggest that SPLCV-KR is a new strain of SPLCV and is importantly placed in the evolutionary progression from curtoviruses to begomoviruses.

KEYWORDS

sweet potato leaf curl virus; sweet potato leaf curl disease; phylogenetic analysis; infectious clone; biolistic infection.

Anisotropic change in THz resonance of planar metamaterials by liquid crystal and carbon nanotube

THz metamaterials are employed to examine changes in the meta-resonances when two anisotropic organic materials, liquid crystal and carbon nanotubes, are placed on top of metamaterials. In both anisotropic double split-ring resonators and isotropic four-fold symmetric split-ring resonators, anisotropic interactions between the electric field and organic materials are enhanced in the vicinity of meta-resonances. In liquid crystal, meta-resonance frequency shift is observed with the magneto-optical coupling giving rise to the largest anisotropic shift. In carbon nanotube, meta-resonance absorptions, parallel and perpendicular to nanotube direction, experience different amount of broadening of Lorentzian oscillator of meta-resonance. Investigation reported here opens the application of metamaterials as a sensor for anisotropic materials.

Molecular characterization of sweet potato leaf curl virus (SPLCV) isolates from Korea: phylogenetic relationship and recombination analysis

The complete DNA genome of sweet potato leaf curl virus (SPLCV) from samples obtained from eight regions was amplified by PCR and characterized in this study. The DNA genome of one group (SPLCV Korea group 1) consisted of 2828 nucleotides and that of the second group (SPLCV Korea group 2) consisted of 2829 nucleotides. Sequence comparisons showed that the genome sequences of SPLCV Korea isolates were closely related to those of SPLCV Brazil isolates (FJ969834, FJ969835, and FJ969836), SPLCV Japan isolate (AB433788), and SPLCV USA isolate (AF104036) with nucleotide sequence identity values ranging from 96-98%. Analysis of the phylogenetic relationship of SPLCV Korea isolates with other begomoviruses revealed that the majority of SPLCV Korea isolates were clustered with SPLCV Brazil isolates (FJ969834, FJ969835, and FJ969836). Recombination analysis results revealed three recombinations among SPLCV Korea isolates, SPLCV isolates from Brazil and Japan, and ipomoea yellow vein virus (IYVV) Italy isolate.