W. Dwayne Lawrence
Brown University
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Featured researches published by W. Dwayne Lawrence.
Developmental Biology | 1984
Osamu Taguchi; Gerald R. Cunha; W. Dwayne Lawrence; Stanley J. Robboy
A study was undertaken to determine (1) the effects of endogenous Müllerian inhibiting substance (MIS) on the developing human fetal genital tract; (2) the time in fetal life when MIS is first capable of inhibiting the growth of the embryonic Müllerian ducts; and (3) the reversibility of the effects of MIS on the developing male Müllerian ducts. Human fetal reproductive tracts were transplanted and grown for sustained periods in vivo in athymic nude mice. The genital tracts from 12 male human fetuses, ages 51 to 68 days postovulation, were grafted without their associated gonads into castrated murine hosts and grown for 30 to 70 days. Controls consisted of genital tracts from 8 female human fetuses, ages day 53 to 70 that were grown under identical conditions. Male specimens grew to approximately one-half the size of female specimens and disclosed varying degrees of inhibition of the Müllerian duct system from absence of the Müllerian ducts in older specimens (after Day 63) to poorly segregated segments of stroma as the mildest defect (less than Day 61). It is concluded that (1) MIS secretion by the embryonic testes probably begins before Day 51 of gestation; (2) the effects of MIS are progressive during the so-called critical window; (3) the effects of MIS are permanent; and (4) the mesenchyme is an important target of MIS.
Cancer | 2003
Rouba Ali-Fehmi; Mingxin Che; Ibrahim Khalifeh; John M. Malone; Robert Morris; W. Dwayne Lawrence; Adnan R. Munkarah
Cyclooxygenase‐2 (COX‐2) seems to be involved at various steps in the processes of malignant transformation and tumor progression. Investigations have shown that COX‐2 overexpression is associated with increased proliferation, reduced apoptosis, and angiogenesis.
International Journal of Gynecological Pathology | 1995
Suzanne M. Jacques; Faisal Qureshi; W. Dwayne Lawrence
A total of 161 uteri removed for endometrial cancer were studied in order to characterize the histopathologic features of the endometrial surface epithelium. Of these, 116 had endometrioid endometrial adenocarcinoma, and 45 had other endometrial cancers. A total of 57 (49%) of the endometrioid endometrial adenocarcinomas showed the following surface epithelial changes: seven had a conspicuous microglandular pattern simulating cervical microglandular hyperplasia; 17 had syncytial aggregates of relatively bland-appearing eosinophilic cells, frequently with papillary or squamoid differentiation simulating papillary syncytial change or other endometrial epithelial metaplasias; and 33 had mixed patterns. The surface epithelial changes varied in extent from rare foci to extensive surface replacement and were largely confined to FIGO grade I and II tumors. Cytologic atypicality varied from mild to moderate and was consistently less than that of the underlying carcinoma. Similar changes were present in some of the prior curettings; in some scanty curettings an unequivocal diagnosis of carcinoma was not possible. Consequently, further clinical investigation is indicated if these changes are present in scanty curettings from postmenopausal women.
Cancer | 1983
Yao S. Fu; Lundy Braun; Keerti V. Shah; W. Dwayne Lawrence; Stanley J. Robboy
Fifty‐four cervical condylomatous lesions, with and without nuclear atypia, from 42 women, were studied with the Feulgen microspectrophotometric technique for nuclear DNA quantitation and an immunoperoxidase technique for human papillomavirus (HPV) antigen. All ordinary cervical condylomas (without atypia/dysplasia) had a diploid or polyploid nuclear DNA distribution; 61% had detectable HPV antigen. Among the cervical condylomas with atypia/dysplasia, 55% (17/31) had diploid or polyploid nuclear DNA pattern, and, of these, 59% (10/17) had demonstrable papillomavirus antigen. Fourteen (45%) were aneuploid lesions, 2 of which had a small number of cells with papillomavirus antigen (14%). These findings suggest that the majority of cervical condylomas are related to papillomavirus infection. That lesions with dysplasia, including high degrees of dysplasia, may also exhibit coexistence of papillomavirus infection suggests the possibility of an infectious etiology in the genesis of cervical squamous neoplasia.
Reproductive Sciences | 2010
M. Ruhul Quddus; C. James Sung; Cunxian Zhang; W. Dwayne Lawrence
Most endometrial carcinomas contain only 1 Müllerian cell type although the presence of 2 or more cell types within 1 tumor, for example a predominantly low-grade endometrioid carcinoma with a minor component (arbitrarily defined as 30% or less) of high-grade serous and/or clear cell carcinoma, is not uncommon. The current study attempts to evaluate whether the presence of minor serous or clear cell components exerts an adverse effect on the prognosis in stage-I endometrial carcinomas of ‘‘mixed-type.’’ The study cases include 22 cases of stage-I endometrioid carcinoma with a minor component of serous carcinoma and 14 cases of endometrioid carcinoma with a minor component of clear cell carcinoma. Minor components were arbitrarily defined as representing anywhere between 5% and 30% of the total tumor. The study cases were compared with 56 cases of histologically pure age-matched and stage-matched endometrioid carcinomas, 6 pure serous carcinomas, and 13 pure clear cell carcinomas. All study and control cases were fully staged. Treatment history and outcome status were obtained and follow-up ranged from 56 to 140 months. Our study suggests that the presence of minor components of serous and clear cell carcinoma, defined as between 5% and 30%, within a mixed-type endometrial carcinoma appears to adversely influence the long-term survival of stage-I tumors, although a larger study is needed to corroborate our findings.
Human Pathology | 2003
Cunxian Zhang; Peng Zhang; C. James Sung; W. Dwayne Lawrence
Molecular alterations that are associated with clinicopathological features of extramammary Pagets disease of the vulva (PDV) are poorly understood. Consequently, we have investigated whether a correlation exists between overexpression of p53 protein and various clinicopathologic features of PDV. Our study group comprises 10 primary noninvasive PDVs, 3 primary PDVs with minimal invasion, and 1 primary PDV with frank invasion. Recurrence in the form of noninvasive PDV was seen in 4 patients with previously noninvasive PDVs and in 1 patient who previously had PDV with minimal invasion. Metastases to the inguinal lymph nodes were associated with the 1 PDV with frank invasion and 1 of the PDVs with minimal invasion. An immunohistochemical study of p53 expression was performed on paraffin-embedded tissue. Negative p53 immunostaining was seen in all of the primary noninvasive PDVs as well as their recurrences. Positive p53 immunostaining was observed in the invasive as well as the intraepidermal components of all of the primary PDVs with invasion, the metastatic tumors in the inguinal lymph nodes, and the recurrent PDV associated with prior invasion, indicating a possible role of p53 in the progression of PDV. To our knowledge, our observation of p53 overexpression in the intraepidermal component of PDVs associated with invasion is the first to be reported in the literature. This observation may prove helpful in identifying stromal invasion in small biopsies. We also report for the first time an association between high nuclear grade in PDV and the propensity for inguinal lymph node metastasis.
International Journal of Gynecological Pathology | 2007
Robert E. Emerson; Mingsheng Wang; Fang Liu; W. Dwayne Lawrence; Fadi W. Abdul-Karim; Liang Cheng
Summary: Patients with ovarian serous tumors of low malignant potential (LMP) are commonly found to have peritoneal implants. Less commonly, similar lesions are seen in lymph nodes, sometimes in association with endosalpingiosis. We compared these lesions to the coexisting ovarian LMP tumors to determine whether they are clonally related to the ovarian neoplasm. Seventeen patients with serous LMP tumors present at 2 or more sites were identified. Tissue samples were microdissected from formalin-fixed paraffin-embedded tissue blocks. Samples of normal tissue, the ovarian LMP tumors, peritoneal LMP implants, and LMP inclusions within lymph nodes were obtained. Genomic DNA was extracted from the samples, and polymerase chain reaction and X-chromosome inactivation (human androgen receptor assay) analysis were performed. The pattern of X-chromosome inactivation could be determined in 15 of the 17 cases, and nonrandom X-chromosome inactivation was observed in 13 of these cases. Twelve of these cases included both ovarian and extraovarian LMP tumors. In 9 of these 12 cases, the extraovarian LMP tumor shared a similar pattern of nonrandom X-chromosome inactivation with the ovarian tumor. In these cases, the shared inactivation pattern was seen at 1 extraovarian site (3 cases), 2 extraovarian sites (4 cases), 5 extraovarian sites (1 case), and 7 of 8 extraovarian sites (1 case). In the remaining 3 cases, opposite patterns of nonrandom X-chromosome inactivation were seen. These data suggest that, in most cases, serous LMP tumor implants and lymph node inclusions share a common clonal origin with the associated ovarian tumors. However, in at least some cases, the implants and inclusions seem to arise independently from the associated ovarian serous LMP tumors.
International Journal of Gynecological Pathology | 2004
Ibrahim Khalifeh; Adnan R. Munkarah; Fulvio Lonardo; John M. Malone; Robert T. Morris; W. Dwayne Lawrence; Rouba Ali-Fehmi
Summary:The objective of this study was to compare the immunohistochemical profile and clinical course of primary peritoneal serous carcinoma (PPC) and primary ovarian serous carcinoma (OSC). These entities are virtually indistinguishable morphologically, but their differential molecular and clinical features are incompletely characterized. Twenty-nine cases of high-grade, high-stage PPC and 96 cases of stage matched OSCs were compared. PPC was identified based on the criteria proposed by the Gynecologic Oncology Group. The tumors were staged according to International Federation of Gynecology and Obstetrics criteria for ovarian cancer and graded according to World Health Organization criteria. Expression of Cox-2, CD-34, bcl-2, and p53 was compared in the two tumors and correlated with clinical data including stage, age, race, and overall survival. Although the median survival, using Kaplan-Meier test, of patients with OSC (1060 days, 35.3 months) was longer than those with PPC (708 days, 23.6 months) the difference was not statistically significant. However, Cox-2 expression was correlated with microvessel density in PPC (p=0.026) and OSC cases (p=0.005), and high expression of Cox-2 correlated with lower survival rate in OSC cases (p=0.045) but not in PPC cases (p=0.12). These findings, coupled with the morphologic overlap existing between OSC and PPC, support the view that they represent related pathologic entities.
International Journal of Gynecological Pathology | 2005
Ibrahim Khalifeh; Adnan R. Munkarah; Veronica Schimp; Robert T. Morris; W. Dwayne Lawrence; Rouba Ali-Fehmi
The transmembrane-tyrosine-kinase receptor, c-kit, is involved in cell differentiation and has been found to be expressed in normal human cell types and solid tumors. This study was designed to investigate the effects of c-kit expression on: 1) tumor proliferation and apoptosis, and 2) survival in patients with high-grade advanced stage ovarian serous carcinoma (OSC). We identified 118 patients with high-grade advanced stage OSC from our files. Clinical data, including demographics and overall survival, were collected. Immunohistochemical panel consisting of c-kit, ki-67, p53, and bcl-2 was performed. C-kit was categorized as positive if any cytoplasmic or membranous staining pattern was identified. Correlation between c-kit expression and the other markers was performed. Survival analysis was performed using COX proportional hazards regression and Kaplan-Meier test. Of 118 cases, 25 (21.2%) expressed c-kit. Of 93 c-kit-negative tumors, 87.1% had a high proliferation index. High p53 and bcl-2 expression was identified in 96 (81.4%) and 59 (50%) cases respectively. No significant statistical correlation was identified between c-kit and apoptosis markers. Tumors lacking c-kit expression showed a trend toward having high proliferation index, but this did not achieve statistical significance (p = 0.07). Of the seven variables included in the multivariate survival analysis, only c-kit (odds ratio, 2.12; 95% confidence interval, 08-4.17; p = 0.02) and ki-67 (odds ratio, 1.9; 95% confidence interval, 1.1-3.1; p = 0.03) showed an independent statistically significant impact on survival. High-grade advanced stage OSC lacking c-kit expression correlates with poor outcome. Interestingly, cases lacking c-kit expression also showed a trend to have high proliferation index.
International Journal of Gynecological Pathology | 2004
Rouba Ali-Fehmi; Faisal Qureshi; W. Dwayne Lawrence; Suzanne M. Jacques
We evaluated apoptosis, proliferation, and p53 and bcl-2 expression in a spectrum of intraepithelial and invasive endocervical glandular lesions currently recognized by the World Health Organization as adenocarcinoma in situ, lesions with atypia “less than adenocarcinoma in situ ” (endocervical glandular dysplasia and endocervical glandular atypia), and invasive adenocarcinoma. Aside from nuclear atypia, increased mitotic activity and apoptosis are consistent and closely correlated morphologic features of endocervical adenocarcinoma in situ. Apoptotic bodies and mitotic figures were counted in 32 examples of normal endocervical glands, 35 of endocervical glandular atypia, 30 of endocervical glandular dysplasia, 34 of adenocarcinoma in situ, and 30 of invasive adenocarcinoma. These results were correlated with immunohistochemical staining for MIB1, bcl-2, and p53 performed on 20 examples of each. Mitotic counts, p53 expression, and bcl-2 expression all increased significantly and in proportion to the degree of atypia in the spectrum of endocervical lesions. Apoptotic body counts and MIB1 expression also increased significantly with increasing atypia, but showed higher levels in adenocarcinoma in situ than in invasive adenocarcinoma. Apoptosis correlates with proliferation as measured by mitotic counts and MIB1, and also with p53 and bcl-2 expression. Apoptosis appears to be an important mechanism in the pathogenesis of endocervical glandular lesions and may be useful as an aid in their evaluation and diagnosis.