• 대한방사성의약품학회지
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• 제1권2호
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• pp.118-122
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• 2015

Suicidal gene therapy is based on the transduction of tumor cells with "suicide" genes encoding for prodrug-activating enzymes that render target cells susceptible to prodrug treatment. Suicidal gene therapy results in the death of tumor with the expression of gene encoding enzyme that converts non-toxic prodrug into cytotoxic product. Cytochrome P450 4B1 (CYP4B1) activates 4-ipomeanol (4-IPO) or 2-aminoanthracene (2-AA) to cytotoxic furane epoxide and unsaturated dialdehyde intermediate.In this study, therapeutic effects of suicidal gene therapy with rabbit CYP4B1/2-AA or 4-IPO system were evaluated in HT-29 (human colon cancer cell). pcDNA-CYP4B1 vector was transfected into HT-29 by lipofection and stable transfectant was selected by treatment of hygromycin ($500{\mu}g/mL$) for 3 weeks. Reverse transcription polymerase chain reaction (RT-PCR) analysis was performed for confirmation of CYP4B1 expression in CYP4B1 gene transduced cell. The cytotoxic effects of CYP4B1 transduced cell were determined using dye-exclusion assay after treatment of 2-AA or 4-IPO for 96 hrs. Dye-exclusion assay showed that $IC_{50}$ of HT-29 and CYP4B1 transduced HT-29 was 0.01 mM and 0.003 mM after 4-IPO or 2-AA treatment at 96 hrs exposure, respectively. In conclusion, CYP4B1 based prodrug gene therapy probably have the potential for treatment of colorectal adenocarcinoma.

• 대한비뇨기종양학회지
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• 제15권3호
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• pp.131-136
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• 2017

Purpose: The aim of this study is to investigate the criteria of biochemical recurrence (BCR) and follow-up periods and methods with and without blood and imaging test of urologic oncology before established guidelines of prostate cancer in Korea. Materials and Methods: In December 2015, we sent the questionnaire to urologic oncologist in academic hospital and received the answer from 108 urologic oncologist (50%). Also, we analyzed the data of 1,141 patients underwent radical prostatectomy in 2005 from Korean Medical Insurance. Results: In follow-up, 72 physicians (66.7%) performed blood test every 3 months, 51 physicians (47.2%) performed imaging study in case of BCR. Bone scan was the most common imaging study in the follow-up (74 physicians, 68.5%). But, bone scan was only performed in case of BCR (43 physicians, 39.8%). The criteria of BCR was PSA 0.2 ng/mL (75 physician, 69.4%), 76 physicians (70.4%) was performed different follow-up according to risk of patients. In Korean Medical Insurance data analysis, PSA were performed average 2 times every year and magnetic resonance imaging, computed tomography, Bone scan were performed average 0.1, 0.2, 0.1 times every year, respectively. Conclusions: The criteria of BCR and the follow-up of prostate cancer patients in Korea were similar Korean prostate cancer guidelines. Blood and imaging test might be increased compared to 10 years ago, it is necessary to compare the Korean Medical Insurance data between 10 years ago and present.

• Korean Journal of Radiology
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• 제22권4호
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• pp.559-567
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• 2021

Objective: To evaluate the impact of multiparametric magnetic resonance imaging (mpMRI) before confirmatory prostate biopsy in patients under active surveillance (AS). Materials and Methods: This retrospective study included 170 patients with Gleason grade 6 prostate cancer initially enrolled in an AS program between 2011 and 2019. Prostate mpMRI was performed using a 1.5 tesla (T) magnetic resonance imaging system with a 16-channel phased-array body coil. The protocol included T1-weighted, T2-weighted, diffusion-weighted, and dynamic contrast-enhanced imaging sequences. Uroradiology reports generated by a specialist were based on prostate imaging-reporting and data system (PI-RADS) version 2. Univariate and multivariate analyses were performed based on regression models. Results: The reclassification rate at confirmatory biopsy was higher in patients with suspicious lesions on mpMRI (PI-RADS score ≥ 3) (n = 47) than in patients with non-suspicious mpMRIs (n = 61) and who did not undergo mpMRIs (n = 62) (66%, 26.2%, and 24.2%, respectively; p < 0.001). On multivariate analysis, presence of a suspicious mpMRI finding (PI-RADS score ≥ 3) was associated (adjusted odds ratio: 4.72) with the risk of reclassification at confirmatory biopsy after adjusting for the main variables (age, prostate-specific antigen density, number of positive cores, number of previous biopsies, and clinical stage). Presence of a suspicious mpMRI finding (adjusted hazard ratio: 2.62) was also associated with the risk of progression to active treatment during the follow-up. Conclusion: Inclusion of mpMRI before the confirmatory biopsy is useful to stratify the risk of reclassification during the biopsy as well as to evaluate the risk of progression to active treatment during follow-up.

• Bulletin of the Korean Chemical Society
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• 제25권4호
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• pp.506-510
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• 2004

There have been intensive studies concerning $[^{11}F]$choline ($[^{11}F]$methyldimethyl( ${\beta}$ -hydroxyethyl) ammonium) (1) which is known as a very effective tracer in imaging various human tumors localized in brain, lung, esophagus, rectum, prostate and urinary bladder using Positron Emission Tomography (PET) and there is increasing interest in $^{18}F$ labelled choline (2) and proved to be useful to visualize prostate cancer. We have prepared six $^{18}F$ labelled alkyl choline derivatives (3a-3c, 4a-4c) from ditosylated and dibrominated alkanes in moderate yields. The six alkyl tosylate or bromate ammonium salts have been synthesized as precursors. Radiofluorination was achieved by the treatment of precursors with $^{18}F$ - in the presence of Kryptofix-2.2.2.. The labeling yields varied ranging from 7 to 25%.

• Nuclear Medicine and Molecular Imaging
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• 제40권5호
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• pp.237-242
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• 2006

Knowledge of molecular mechanisms governing malignant transformation brings new opportunities for therapeutic intervention against cancer using novel approaches. One of them is gene therapy based on the transfer of genetic material to an organism with the aim of correcting a disease. The application of gene therapy to the cancer treatment has led to the development of new experimental approaches such as suicidal gene therapy, inhibition of oncogenes and restoration of tumor-suppressor genes. Suicidal gene therapy is based on the expression in tumor cells of a gene encoding an enzyme that converts a prodrug into a toxic product. Representative suicidal genes are Herpes simplex virus type 1 thymidine kinase (HSV1-tk) and cytosine deaminase (CD). Especially, physicians and scientists of nuclear medicine field take an interest In suicidal gene therapy because they can monitor the location and magnitude, and duration of expression of HSV1-tk and CD by PET scanner.

• Investigative Magnetic Resonance Imaging
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• 제22권4호
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• pp.272-276
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• 2018

Extra-articular tenosynovial giant cell tumor (TS-GCT) in retropharyngeal space is a rare case. We found only two case reports in the literature, in which one was located in retropharynx or prevertebral space of the cervical spine. We describe a rare case of TS-GCT in the retropharynx, which was initially misdiagnosed as oropharyngeal cancer. Furthermore, we want to assure that extraarticular diffuse type TS-GCT should be considered in the differential diagnosis of lesions showing low signal intensity in MRI scan.

• Journal of Digestive Cancer Research
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• 제10권1호
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• pp.16-21
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• 2022

Diagnosis of gastric subepithelial tumors (SETs) is sometimes difficult with conventional endoscopy or tissue sampling with standard biopsy, so non-invasive imaging modalities such as endoscopic ultrasound (EUS) and computed tomography are used to evaluate the characteristics of SETs features (size, location, originating layer, echogenicity, shape). However imaging modalities alone is not able to distinguish among all types of SETs, so histology is the gold standard for obtaining the final diagnosis. For tissue sampling, mucosal cutting biopsy and mucosal incision-assisted biopsy and EUS-guided fine-needle aspiration or biopsy (EUS-FNA or EUS-FNB) is commonly recommended. Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are used for resection of SETs involving the mucosal and superficial submucosal layers, could not treat adequately and safely the SETs involving the deep mucosa and muscularis propria. Submucosal tunneling endoscopic resection (STER) and endoscopic full-thickness resection (EFTR) is used as a therapeutic option for the treatment of SETs with the development of reliable endoscopic closure techniques and tools.

• 한국전자파학회논문지
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• 제20권8호
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• pp.797-805
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• 2009

본 논문에서는 전자파를 이용하여 인체 내 암 조직을 찾아내기 위해 역산란 방법인 BIM(Born Iterative Method)에 적용되는 순방향 해석 알고리즘을 MoM(Method of Moment)으로 구현하였다. 특히 유방암의 전자파 산란 해석을 위해 2차원 유방 단면 구조를 이용하였다. 이 단면 구조를 적분방정식과 2차원 그린함수를 이용하여 정식화한 후 MoM을 적용하여 해석하고 산란 전장을 구하였다. 또한, 유방암 측정 실험 장치를 통해 얻은 모사구조에 대한 측정값과 MoM을 이용한 수치해석 계산 값을 비교하여 결과를 분석하였다.

• 대한영상의학회지
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• 제82권2호
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• pp.493-497
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• 2021

악성 횡문근양 종양은 주로 영유아의 신장에서 발생하는 공격적인 종양이다. 신장 이외의 조직에서 발생한 경우 신외성 악성 횡문근양 종양이라 하고 중추신경계, 간, 뇌, 피부, 연조직 등에서 드물게 보고되었다. 위에서 발생한 악성 횡문근양 종양은 매우 드물다. 저자들은 흑색변을 주소로 내원한 72세 남자의 위에서 발견된 악성 신외성 횡문근양 종양이 림프종과 유사한 영상 소견을 보인 예를 경험하여 보고한다.

• 대한영상의학회지
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• 제85권3호
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• pp.676-681
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• 2024

방골성 지방종은 뼈에 매우 인접한 위치에 생기는 지방종으로 전체 지방종의 약 0.3%를 차지하는 드문 종양이다. 한편 연골지방종은 지방종에서 연골 화생이 발생한 것으로 성숙한 지방조직과 연골조직으로 이루어져 있으며 매우 드물게 보고되고 있다. 따라서 방골성 지방종과 연골지방종의 특징을 모두 보이는 경우는 더욱 드물다. 저자들은 우측 견갑골 부위에 만져지는 덩이 및 통증을 주소로 내원한 55세 여자 환자가 광범위 절제술 후 조직병리검사에서 방골성 연골지방종으로 진단된 증례를 영상 소견을 중심으로 보고한다.