Yen-Chein Lai has completed her Ph.D. at the age of 29 years from National Taiwan University College of Medicine. Her PhD research focused on mechanism analysis of HDV ribozyme activity. She has served as an Assistant Professor in School of Medical Laboratory and Biotechnology of Chung Shan Medical University since 1998. She has had much experience in the teaching of Molecular Diagnostics and Clinical Chemistry courses. Her research aims are the molecular-genetic analysis of patients with certain cancer syndromes. She has published more than 10 papers in reputed journals and has been serving as an editorial board member of repute.
The most accepted theory regarding mature cystic teratomas of the ovary is that they are of parth... more The most accepted theory regarding mature cystic teratomas of the ovary is that they are of parthenogenetic origin from oocyte after the completion of first division. Our previous study demonstrated that the origin of mature cystic teratoma of the uterus is not related to the parthenogenetic process, but is most likely pluripotential stem cell or primordial germ cell before meiosis I. Further studies are needed to clarify the origin of benign mature cystic teratomas of the ovary in Taiwan. In the present study, we investigated the DNA profiles of 9 mature cystic teratomas of the ovary using short tandem repeat analysis with AmpFLSTR SGM Plus, Profiler PCR amplification kits. The methylation statuses of the HhaI sites in the SNRPN, H19DMR, and KvDMR regions were determined on methylation-sensitive multiplex ligation-dependent probe amplification analysis. DNA profiling data from the 9 mature cystic teratomas of the ovary excluded parthenogenetic origin, as most of the 15 short tandem repeat loci were heterozygous on genotyping. There were varying degrees of hypermethylation of SNRPN gene and KvDMR locus in the presence of maternal uniparental disomy in all 9 mature cystic teratomas of the ovary. In light of these results, we further postulated that the origin of these mature cystic teratomas of the ovary is oogonia or primary oocyte before germinal vesicle stage failure of meiosis I.
We have read the article by Ozturk et al. entitled " Epab and Pabpc1 are differentially expressed... more We have read the article by Ozturk et al. entitled " Epab and Pabpc1 are differentially expressed in the postnatal mouse ovaries " [1] with great interest. In that article the authors aimed to characterize the temporal and spatial expression profiles of the Epab and Pabpc1 genes in the postnatal mouse ovaries. They found that Epab and Pabpc1 are differently expressed during postnatal development, and most likely play central roles in oogenesis and folliculogenesis. We are most interested in how to apply the results of this study to the clinical practice of human assisted reproduction. An important issue in infertility is ovarian reserve. The ovarian reserve may involve three distinct aspects: oocyte quality, oocyte quantity, and reproductive potential [2]. Clinicians are often asked: Can I become pregnant at my age? Are aggressive assisted methods the most appropriate for me? Do I need someone to donate eggs? These are usually answered via the results of ovarian reserve tests. A variety of tests are available for determining ovarian reserve [2] including day 3 FSH level, clomiphene citrate challenge, day 3 estradiol level, anti-Müllerian hormone, and imaging studies such as those for antral follicle count. However, each test has its limitations and restrictions. Measuring FSH concentration on the third day of the menstrual cycle is a widespread method. However, different cutoff points and inter cycle variability limit its reliability [3]. Measuring estradiol on the third day of the menstrual cycle results in the same reliability issues and conflicting data [4], and can only be applied in the interpretation of the normal results of FSH test. High FSH level and normal FSH with high estradiol indicate poor response to stimulation and low pregnancy rate. The clomiphene citrate challenge test is used to obtain both day 3 and day 10 FSH concentrations after clomiphene challenge but provides limited additional information to that of basal FSH [5]. Anti-Müllerian hormone is the best and most reliable predictor of poor or excessive ovarian response after stimulation. However, there is no international standard for this test and it is a poor predictor of live birth [6]. Imaging studies required expertise and high quality ultrasound equipment. Antral follicle count is good for predicting poor stimulation and pregnancy outcome. However, in addition to the limitations mentioned above, its low sensitivity restricts its clinical utility [7]. We would like to thank the authors of the study for providing clinicians with another potential method for evaluating the ovarian reserve if the conflicting results from different strains of mice and different probes can be resolved. Epab expression may correlate with response to stimulation or pregnancy rate and become an indicator of ovarian reserve. However, there is still a huge gap to overcome in applying these methods to human. References
Background: Mature cystic teratomas are usually found in the ovaries. They are bilateral in 10 to... more Background: Mature cystic teratomas are usually found in the ovaries. They are bilateral in 10 to 15% of cases and multiple cystic teratomas may be present in one ovary. The aim of this study is to clarify if development of mature cystic teratomas of the ovaries in a single host is metachronous or due to autoimplant or recurrence.
Background: Granulosa cell tumors are rare ovarian malignancies. Their characteristics include un... more Background: Granulosa cell tumors are rare ovarian malignancies. Their characteristics include unpredictable indolent growth with malignant potential and late recurrence. Approximately 95% are of adult type. Recent molecular studies have characterized the FOXL2 402C > G mutation in adult granulosa cell tumor. Our previous case report showed that unique FOXL2 402C > G mutation and defective DNA mismatch repair system are associated with the development of adult granulosa cell tumor. Findings: In this study, the DNA sequences of four genes, MSH2, MLH1, MSH6, and PMS2, in the DNA mismatch repair system were determined via direct sequencing to elucidate the exact mechanism for the development of this granulosa cell tumor. The results showed that two missense germline mutations, T485K and N775L, inactivate the PMS2 gene.
Granulosa cell tumors are rare ovarian malignancies. Their characteristics include unpredictable ... more Granulosa cell tumors are rare ovarian malignancies. Their characteristics include unpredictable late recurrent and malignant behavior. Recent molecular studies have characterized the FOXL2 402C > G mutation in adult-type granulosa cell tumor. In this study, we report an 80-year-old woman with a granulosa cell tumor arising from ovary. She presented with a huge pelvic mass with postmenopausal bleeding. No obvious intraperitoneal tumor implants were observed during operation. Final diagnosis was granulosa-theca cell tumor without capsule invasion. No recurrent disease was noted during 3-year post-operation follow-up period. Molecular studies showed a heterozygous FOXL2 402C > G mutation in the tumor by direct gene sequencing. In addition, DNA replication error, on analysis of the lengths of CAG repeats in androgen receptor gene, revealed defective DNA mismatch repair system in the granulosa cell tumor. We propose that the 402C > G mutation in FOXL2 is critical to the develop...
The most accepted theory regarding mature cystic teratomas of the ovary is that they are of parth... more The most accepted theory regarding mature cystic teratomas of the ovary is that they are of parthenogenetic origin from oocyte after the completion of first division. Our previous study demonstrated that the origin of mature cystic teratoma of the uterus is not related to the parthenogenetic process, but is most likely pluripotential stem cell or primordial germ cell before meiosis I. Further studies are needed to clarify the origin of benign mature cystic teratomas of the ovary in Taiwan. In the present study, we investigated the DNA profiles of 9 mature cystic teratomas of the ovary using short tandem repeat analysis with AmpFLSTR SGM Plus, Profiler PCR amplification kits. The methylation statuses of the HhaI sites in the SNRPN, H19DMR, and KvDMR regions were determined on methylation-sensitive multiplex ligation-dependent probe amplification analysis. DNA profiling data from the 9 mature cystic teratomas of the ovary excluded parthenogenetic origin, as most of the 15 short tandem repeat loci were heterozygous on genotyping. There were varying degrees of hypermethylation of SNRPN gene and KvDMR locus in the presence of maternal uniparental disomy in all 9 mature cystic teratomas of the ovary. In light of these results, we further postulated that the origin of these mature cystic teratomas of the ovary is oogonia or primary oocyte before germinal vesicle stage failure of meiosis I.
We have read the article by Ozturk et al. entitled " Epab and Pabpc1 are differentially expressed... more We have read the article by Ozturk et al. entitled " Epab and Pabpc1 are differentially expressed in the postnatal mouse ovaries " [1] with great interest. In that article the authors aimed to characterize the temporal and spatial expression profiles of the Epab and Pabpc1 genes in the postnatal mouse ovaries. They found that Epab and Pabpc1 are differently expressed during postnatal development, and most likely play central roles in oogenesis and folliculogenesis. We are most interested in how to apply the results of this study to the clinical practice of human assisted reproduction. An important issue in infertility is ovarian reserve. The ovarian reserve may involve three distinct aspects: oocyte quality, oocyte quantity, and reproductive potential [2]. Clinicians are often asked: Can I become pregnant at my age? Are aggressive assisted methods the most appropriate for me? Do I need someone to donate eggs? These are usually answered via the results of ovarian reserve tests. A variety of tests are available for determining ovarian reserve [2] including day 3 FSH level, clomiphene citrate challenge, day 3 estradiol level, anti-Müllerian hormone, and imaging studies such as those for antral follicle count. However, each test has its limitations and restrictions. Measuring FSH concentration on the third day of the menstrual cycle is a widespread method. However, different cutoff points and inter cycle variability limit its reliability [3]. Measuring estradiol on the third day of the menstrual cycle results in the same reliability issues and conflicting data [4], and can only be applied in the interpretation of the normal results of FSH test. High FSH level and normal FSH with high estradiol indicate poor response to stimulation and low pregnancy rate. The clomiphene citrate challenge test is used to obtain both day 3 and day 10 FSH concentrations after clomiphene challenge but provides limited additional information to that of basal FSH [5]. Anti-Müllerian hormone is the best and most reliable predictor of poor or excessive ovarian response after stimulation. However, there is no international standard for this test and it is a poor predictor of live birth [6]. Imaging studies required expertise and high quality ultrasound equipment. Antral follicle count is good for predicting poor stimulation and pregnancy outcome. However, in addition to the limitations mentioned above, its low sensitivity restricts its clinical utility [7]. We would like to thank the authors of the study for providing clinicians with another potential method for evaluating the ovarian reserve if the conflicting results from different strains of mice and different probes can be resolved. Epab expression may correlate with response to stimulation or pregnancy rate and become an indicator of ovarian reserve. However, there is still a huge gap to overcome in applying these methods to human. References
Background: Mature cystic teratomas are usually found in the ovaries. They are bilateral in 10 to... more Background: Mature cystic teratomas are usually found in the ovaries. They are bilateral in 10 to 15% of cases and multiple cystic teratomas may be present in one ovary. The aim of this study is to clarify if development of mature cystic teratomas of the ovaries in a single host is metachronous or due to autoimplant or recurrence.
Background: Granulosa cell tumors are rare ovarian malignancies. Their characteristics include un... more Background: Granulosa cell tumors are rare ovarian malignancies. Their characteristics include unpredictable indolent growth with malignant potential and late recurrence. Approximately 95% are of adult type. Recent molecular studies have characterized the FOXL2 402C > G mutation in adult granulosa cell tumor. Our previous case report showed that unique FOXL2 402C > G mutation and defective DNA mismatch repair system are associated with the development of adult granulosa cell tumor. Findings: In this study, the DNA sequences of four genes, MSH2, MLH1, MSH6, and PMS2, in the DNA mismatch repair system were determined via direct sequencing to elucidate the exact mechanism for the development of this granulosa cell tumor. The results showed that two missense germline mutations, T485K and N775L, inactivate the PMS2 gene.
Granulosa cell tumors are rare ovarian malignancies. Their characteristics include unpredictable ... more Granulosa cell tumors are rare ovarian malignancies. Their characteristics include unpredictable late recurrent and malignant behavior. Recent molecular studies have characterized the FOXL2 402C > G mutation in adult-type granulosa cell tumor. In this study, we report an 80-year-old woman with a granulosa cell tumor arising from ovary. She presented with a huge pelvic mass with postmenopausal bleeding. No obvious intraperitoneal tumor implants were observed during operation. Final diagnosis was granulosa-theca cell tumor without capsule invasion. No recurrent disease was noted during 3-year post-operation follow-up period. Molecular studies showed a heterozygous FOXL2 402C > G mutation in the tumor by direct gene sequencing. In addition, DNA replication error, on analysis of the lengths of CAG repeats in androgen receptor gene, revealed defective DNA mismatch repair system in the granulosa cell tumor. We propose that the 402C > G mutation in FOXL2 is critical to the develop...
Uploads
Papers by Yen-chein Lai