Showing papers by "Sug Hyung Lee published in 1998"

A simple, precise and economical microdissection technique for analysis of genomic DNA from archival tissue sections

Abstract: Formalin-fixed and paraffin-embedded tissues are valuable resources for retrospective analysis of the molecular changes in DNA present in tumour tissues. One common problem that precludes an accurate DNA analysis in a human tissue sample is cellular heterogeneity. We have developed a simple and inexpensive, but micrometrically precise, microdissection technique that allows for selective isolation of minute cell clusters and even single cells from archival tissue sections. The features of our technique include use of a 30G1/2 needle affixed to a mechanical micromanipulator as a dissector sharp enough to be used for dissection of even single cells and use of the stage and focus control knobs of the microscope to scrape the target cells instead of moving the needle during microdissection. The main advantages of this technique over the current methods lie in its simplicity, low cost, easy handling and precision.

Frequent Somatic Mutations in Serine/Threonine Kinase 11/Peutz-Jeghers Syndrome Gene in Left-sided Colon Cancer

Abstract: We analyzed somatic mutation and loss of heterozygosity (LOH) in the serine/threonine kinase 11 (STK11)/Peutz-Jeghers syndrome gene in 49 colorectal tumors in three different stages of a dysplasia-carcinoma sequence. We detected LOH in 10 of 19 (52.6%) informative colorectal cancers at loci D19S886 and/or D19S883, but no LOH was observed in 25 informative adenomas. We detected a total of 9 somatic mutations [7 of 13 (53.8%) left-sided colon cancers and 2 of 7 (28.6%) left-sided adenomas with high-grade dysplasia], but no mutations were detected in right-sided colon tumors. Of the nine mutations, one was a frameshift mutation (the same mutation detected in Peutz-Jeghers syndrome family previously), and the other eight were missense mutations. This results indicate that STK11 is a tumor suppressor gene and that genetic changes of STK11 play an important role in left-sided colon cancer carcinogenesis.

Fas ligand is expressed in normal skin and in some cutaneous malignancies

Abstract: Fas, a cell surface receptor and member of the tumour necrosis factor receptor superfamily, induces apoptosis upon oligomerization by its ligand (Fas ligand: FasL). Detailed studies have revealed that Fas is broadly expressed in normal human tissues, but relatively little is known about the range of cell types capable of expressing FasL. The aim of this study was to determine the in vivo patterns of expression of Fas and FasL in human skin tissues. Immunohistochemistry was performed using paraffin-embedded samples of normal and neoplastic skin tissues. In normal skin, FasL was expressed in the epidermis, sebaceous glands, sweat glands and outer root sheath of the hair. In squamous cell carcinomas (SCC), all cases analysed expressed FasL at high levels, whereas 60% of basal cell carcinomas (BCC) were positive for FasL. Expression of Fas in normal skin was observed in the basal and spinous layers of the epidermis, the outer root sheath of the hair, and the sebaceous glands. Expression of Fas was observed in all the SCC tested and none of the BCC tested. Expression of FasL by normal cells and tumour cells in skin tissue, demonstrated for the first time in the present study, may provide an important clue to understanding skin physiology, and immune evasion of skin tumours.

A distinct region of chromosome 19p13.3 associated with the sporadic form of adenoma malignum of the uterine cervix

Abstract: Adenoma malignum (AM) is known to be one of the malignant tumors that is commonly associated with Peutz-Jeghers syndrome. Recently, the genetic locus of Peutz-Jeghers syndrome was mapped to the telomeric region of chromosome 19p. We analyzed nine sporadic cases of AM with high-density loss of heterozygosity to study the region of chromosome 19p13.2-13.3 using eight microsatellite markers. Our deletion mapping data revealed a distinct region with 100% loss of heterozygosity frequency at marker D19S216. This result indicates that a putative tumor suppressor gene for AM is located at D19S216 on chromosomal band 19p13.3 and plays an important role in AM tumorigenesis.

Immunohistochemical analysis of Fas ligand expression in sarcomas. Sarcomas express high level of FasL in vivo

Abstract: Fas ligand (FasL) and its receptor, Fas, play a key role in the regulation of apoptosis within the immune system. Several prior experimental studies of Fas ligand expression in tumors have suggested a mechanism that enables tumors to evade immune destruction by inducing apoptosis in activated lymphocytes near the tumor cells. Many types of carcinomas have been shown to express FasL, but at present nothing is known about the range of sarcomas capable of expressing FasL in vivo. The aim of this study was to determine the in vivo patterns of FasL expression in human sarcomas. Archival paraffin-embedded tissues of 57 sarcomas and 30 carcinomas were analyzed by immunohistochemistry for the expression of FasL. FasL immunoreactivity was seen in 39 of 57 (68%) sarcomas, including 10 of 10 rhabdomyosarcomas, 5 of 5 malignant schwannomas, 2 of 2 Ewing's sarcomas, 8 of 11 malignant fibrous histiocytomas, 4 of 5 angiosarcomas, 2 of 5 synovial sarcomas, 2 of 5 liposarcomas, 3 of 5 leiomyosarcomas, 2 of 6 osteosarcomas, and 1 of 3 chondrosarcomas. All carcinomas tested (10 gastric adenocarcinomas, 10 hepatocellular carcinomas, and 10 renal cell carcinomas) were positive for FasL. These results demonstrate that FasL expression in sarcomas, although less frequent than in carcinomas, is widespread among the sarcoma types, and suggest that FasL might contribute to the immune escape of sarcomas through killing Fas-bearing lymphocytes.

Acute and Chronic Eosinophilic Pneumonia Clinical and Laboratory Findings

Abstract: 연구배경: 만성 호산구성 폐렴은 장기간의 호흡기계 증상, 흉부 엑스선상의 미만성 침윤, 폐 및 말초혈액의 호산구증 및 스테로이드 치료에 극적인 반응 등으로 특징지어지는 만성적이고 재발되는 간질성 폐 질환이다. 급성 호산구성 폐렴은 만성 호산구성 폐렴과 유사하나 임상경과가 빠르고 스테로이드 치료로 호전되며 재발이 없는 질환으로 알려져 있으며, 최근에는 진단 기준을 포함한 급성 호산구성 폐렴에 대한 재평가가 시도되고 있는 실정이며, 급성 호산구성 폐렴의 진단 기준이 다소 제한적이라는 연구도 보고되고 있다. 저자 등은 본원에 내원한 급성 및 만성 호산구성 폐렴환자의 임상적인 특정과 임상경과를 알아보고 서로 비교하여보았다. 방 법: 1992년부터 1997년까지 가톨릭 의과대학 7개 부속 병원에서 급성 및 만성 호산구성 폐렴으로 진단된 16예의 임상상을 요약하였다. 급성 및 만성 호산구성 폐렴의 진단 기준으로는 기침, 발열, 호흡곤란의 호흡기계 증상이 있고, 흉부 X-선과 전산화 단층촬영에서 폐침윤이 있는 환자로, 폐 호산구증은 기관지 폐포 세척과 경기관지 폐생검 및 개흉 폐생검으로 진단하였으며, 호산구증을 일으키는 기저질환이 있는 경우는 제외하였다. 곁 과: 16명의 환자 중 급성 호산구성 폐렴환자가 7명 (남자 5명, 여자 2명), 만성 호산구성 폐렴환자가 9명 (남자 5명, 여자 4명) 이었다. 평균 연령은 AEP 환자 $24.6{\pm}7.9$ 세, CEP환자 $55.4{\pm}15.12$ 세로 CEP환자에서 높은 경향을 보였으며 (p $38^{\circ}C$ 이상의 고혈이 AEP 환자 100%(7/7), CEP환자는 11%(1/9)가 있었다. 내원 전 증상의 기간은 AEP환자가 $2.6{\pm}1$ 일, CEP환자가 $44.7{\pm}25.5$ 일이었다 (p $186{\pm}8,134/mm^3$ , CEP환자 $12,867{\pm}6,040/mm^3$ 이었고, 호산구분획은 AEP환자 $6.6{\pm}6.7%$ (0~20%), CEP환자 $11.3{\pm}21.1%$ (0~65%) 이었으며 AEP환자는 추적검사에서 내원 4~7 병일째 (23.7~51%) 가장 높았다, 평균 말초 혈액 호산구 수는 AEP환자 $939{\pm}1,042/mm^3$ , CEP환자 $2,104{\pm}4,966/mm3^$ 이었다. 기관지 폐포 세척액 검사에서 평균 호산구분획은 AEP환자 $32.4{\pm}14.5%$ (18~47%), CEP환자 $35.8{\pm}26.7%$ (15.3~88.2%) 이었다. 동맥혈 가스 검사상 평균 $PaO_2$ 는 AEP환자 $44.1{\pm}15.5mmHg$ , CEP환자 $62.7{\pm}6.9mmHg$ 로 AEP환자에서 더 낮았다 (p 【Background: Chronic eosinophilic pneumonia(CEP) is interstitial lung disease characterized by multiple infiltration on radiographic study, accumulation of eosinophils in the alveolar space and interstitium of the lung, chronic persistent symptoms and possible relapse. Acute eosinophilic pneumonia(AEP) is a recently described illness, characterized by rapid clinical course, acute respiratory insufficiency and no relapse. Method : To better characterize acute and chronic eosinophilic pneumonia, we studied the clinical and laboratory features of 16 patients(AEP : 7 patients, CEP : 9 patients), which were clinico-pathohistologically diagnosed and not to be associated with organic disorders producing peripheral blood eosinophilia. Results: The mean age was higher for patients with CEP than for patients with AEP ( $55.4{\pm}15.1$ vs. $24.6{\pm}7.9$ years, p $38^{\circ}C$ ) was presented in all patients of AEP and in one patient(11%) of CEP. All patients of AEP and eight patients (89%) of CEP showed bilateral pulmonary infiltrates, and 6 patients(86%) of AEP and 2 patients(22%) of CEP showed pleural effusion in chest radiograph. The mean white blood cell count of AEP and CEP were $17,186/mm^3$ and $12,867/mm^3$ , respectively. The mean peripheral blood eosinophil count of AEP and CEP were $939/mm^3$ and $2,104/mm^3$ , respectively. The mean eosinophil fraction of BAL fluid of AEP and CEP were 32.4% (range: 18~47%) and 35.8% (range: 15.3~88.2%), respectively. The mean $PaO_2$ was lower for patients with AEP than for patients with CEP ( $44.1{\pm}15.5$ vs. $62.7{\pm}6.9$ mmHg, p】