Identification of Y-chromosome by Molecular Analysis in Patients with Turner Syndrome / 대한진단검사의학회지

BACKGROUND: It is known that the Y chromosome or Y-specific sequence is present in about 6% of Turner syndrome (TS) patients and that it predisposes them to gonadoblastoma formation with an estimated risk of 15-25%. In this study, we performed a polymerase chain reaction (PCR) in 32 patients with TS to detect Y-specific sequence. The results were compared with those obtained by the fluorescence in situ hybridaization (FISH) method. METHODS: Cytogenetic analysis was performed by phytohaemagglutinin (PHA)-stimulated peripheral lymphocyte cultures, using G-banding. DNA was extracted from peripheral blood for PCR. Seven different sets of oligonucleotide primers, sex determining region Y (SRY), zinc finger gene on the Y chromosome (ZFY), testis specific protein Y (TSPY), DYZ3, DYF49S1, RNA binding motif protein (RBM), and DYZ1, spanning on centromeres and short and long arms of the Y chromosome were used for PCR. FISH was carried out using X and Y chromosome enumeration probe for Xp11.1-q11.1 (DXZ1 locus) and Yp11.1-q11.1 (DYZ3 locus), respectively. RESULTS: Among 32 patients with TS, four (12.5%) were positive for Y specific sequence by PCR. Of these, two patients were detected previously by a cytogenetic analysis: 45,X/47,XYY and 45,X/46,XY. Only one Y specific sequence, DYZ3, was detected by PCR in the other two patients without cytogenetically obvious Y chromosome. Y signal was not detected by FISH for the last two patients. CONCLUSIONS: It may be reasonable to consider using a PCR method to screen for Y-specific sequences in all patients with TS. Even though we did not demonstrate Y-signal by FISH in patients with PCR positive and cytogenetically no obvious Y chromosome, FISH may be another useful method in TS patient, and futher investigation is nessessary.

The Study on Comparing the Expression of the Collagen IV with different Histopathologic Features of the Colorectal Carcinomas

The malignant potential of a tumor is related to its ability to dissociate invasion and seed other sites-metastasis. In either instance, the tumor cells are confronted with a barrier signif icantly composed of type IV collagen. This type IV collagen is a major structural protein of basement membranes. Using immunohistochemical method to detect type IV collagen, intensity of stain and continuity of basement membrane at the tumor-stromal border was studied in surgical specimens from 47 colorectal carcinomas at the Pusan Paik-Hospital. Immunoreactivity was evaluated semi-quantitatively as three categories; Type-1, thick or normal basement membrane with or without minimal discontinuity; Type-2, thin basement membrane with or without moderate discontinuity; Type-3, fragmented or absent basement membrane. Also, in each case the tumor morphologic features were identified. The histologic type, differentiated grade, desmoplastic response, lymphatic and vascular invasion, lymph node involvement, tumor size and modified Dukes' stage were estabilished. Type-1 immunoreactivity was significantly observed in well-differentiated, negative lymph node, Dukes' stage B1/B2 tumors, and Type-3 was in poorly differentiated, positive lymph node, Dukes' stage C2/D. The expres sion of collagen IV in basement membrane was statistically significant correlated with differentiated grade, lymph node metastasis and modified Dukes' stage. By contrast, no statistically significant correlation was found between paucity of type IV collagen and the other parameters. The result suggest that expression of type IV collagen in basement membrane may be a useful prognostic marker, and may play a part in the invasive and metastatic process of colorectal carcinomas.