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1.
Cell ; 146(2): 290-302, 2011 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-21784249

RESUMEN

Macroautophagy mediates the degradation of long-lived proteins and organelles via the de novo formation of double-membrane autophagosomes that sequester cytoplasm and deliver it to the vacuole/lysosome; however, relatively little is known about autophagosome biogenesis. Atg8, a phosphatidylethanolamine-conjugated protein, was previously proposed to function in autophagosome membrane expansion, based on the observation that it mediates liposome tethering and hemifusion in vitro. We show here that with physiological concentrations of phosphatidylethanolamine, Atg8 does not act as a fusogen. Rather, we provide evidence for the involvement of exocytic Q/t-SNAREs in autophagosome formation, acting in the recruitment of key autophagy components to the site of autophagosome formation, and in regulating the organization of Atg9 into tubulovesicular clusters. Additionally, we found that the endosomal Q/t-SNARE Tlg2 and the R/v-SNAREs Sec22 and Ykt6 interact with Sso1-Sec9, and are required for normal Atg9 transport. Thus, multiple SNARE-mediated fusion events are likely to be involved in autophagosome biogenesis.


Asunto(s)
Autofagia , Fagosomas/metabolismo , Proteínas SNARE/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/citología , Familia de las Proteínas 8 Relacionadas con la Autofagia , Proteínas Relacionadas con la Autofagia , Liposomas/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Fosfatidiletanolaminas/metabolismo , Proteínas Qa-SNARE/metabolismo , Saccharomyces cerevisiae/metabolismo
2.
Artículo en Inglés | MEDLINE | ID: mdl-38514907

RESUMEN

BACKGROUND: The 10th revision of the International Classification of Diseases, Clinical Modification (ICD-10) includes diagnosis codes for placenta accreta spectrum for the first time. These codes could enable valuable research and surveillance of placenta accreta spectrum, a life-threatening pregnancy complication that is increasing in incidence. OBJECTIVE: We sought to evaluate the validity of placenta accreta spectrum diagnosis codes that were introduced in ICD-10 and assess contributing factors to incorrect code assignments. METHODS: We calculated sensitivity, specificity, positive predictive value and negative predictive value of the ICD-10 placenta accreta spectrum code assignments after reviewing medical records from October 2015 to March 2020 at a quaternary obstetric centre. Histopathologic diagnosis was considered the gold standard. RESULTS: Among 22,345 patients, 104 (0.46%) had an ICD-10 code for placenta accreta spectrum and 51 (0.23%) had a histopathologic diagnosis. ICD-10 codes had a sensitivity of 0.71 (95% CI 0.56, 0.83), specificity of 0.98 (95% CI 0.93, 1.00), positive predictive value of 0.61 (95% CI 0.48, 0.72) and negative predictive value of 1.00 (95% CI 0.96, 1.00). The sensitivities of the ICD-10 codes for placenta accreta spectrum subtypes- accreta, increta and percreta-were 0.55 (95% CI 0.31, 0.78), 0.33 (95% CI 0.12, 0.62) and 0.56 (95% CI 0.31, 0.78), respectively. Cases with incorrect code assignment were less morbid than cases with correct code assignment, with a lower incidence of hysterectomy at delivery (17% vs 100%), blood transfusion (26% vs 75%) and admission to the intensive care unit (0% vs 53%). Primary reasons for code misassignment included code assigned to cases of occult placenta accreta (35%) or to cases with clinical evidence of placental adherence without histopatholic diagnostic (35%) features. CONCLUSION: These findings from a quaternary obstetric centre suggest that ICD-10 codes may be useful for research and surveillance of placenta accreta spectrum, but researchers should be aware of likely substantial false positive cases.

3.
Histopathology ; 72(5): 766-776, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29197096

RESUMEN

AIMS: Evidence suggests that up to 70% of high-grade serous ovarian carcinomas (HGSCs) arise potentially from fallopian tube fimbriae, and that many of the remaining cases arise from within the ovary in cortical inclusion cysts (CICs) with a Müllerian phenotype (Müllerian-CICs). It has been proposed that Müllerian-CICs arise either from metaplasia of mesothelial ovarian surface epithelium (OSE) entrapped within the ovary after ovulation or from normal tubal cells entrapped postovulation. However, this proposal is controversial. We therefore conducted a study of CICs in women, most of them BRCA1/2 mutation carriers, undergoing risk-reducing salpingo-oophorectomy at our institution from 2000 to 2014. METHODS AND RESULTS: We used immunohistochemistry for PAX8, a Müllerian marker, and calretinin, a mesothelial marker to classify CIC cells. In 499 CICs from 59 women, 72.3% were positive for PAX8 (PAX8+ ): ≥10% of CIC cells positive; 43.5% positive for calretinin (calretinin+ ). The proportion of PAX8+ CICs increased from 62.9% in premenopausal to 80.5% in postmenopausal patients. The proportion of calretinin+ CICs decreased from 52.6% to 35.6%, respectively. There was significant overlap of PAX8 and calretinin positivity: 82 (16.4%) CICs were PAX8+ /calretinin+ ; 43 (40.2%) of these 82 demonstrated PAX8+ /calretinin+ in the same cells. CONCLUSIONS: These results, and the increased ratio of PAX8+ to calretinin+ CICs from premenopausal to postmenopausal, show that many PAX8+ CICs probably arise from metaplasia of OSE-derived CICs. The proportion of PAX+ /calretinin- CICs arising from OSE-derived CICs is unclear, but our results strongly support the proposal that many Müllerian-CICs arise from OSE via metaplasia.


Asunto(s)
Quistes Ováricos/patología , Ovario/patología , Lesiones Precancerosas/patología , Adulto , Anciano , Biomarcadores/análisis , Calbindina 2/análisis , Calbindina 2/biosíntesis , Femenino , Humanos , Metaplasia/patología , Persona de Mediana Edad , Factor de Transcripción PAX8/análisis , Factor de Transcripción PAX8/biosíntesis , Salpingooforectomía
4.
Int J Cancer ; 141(12): 2392-2399, 2017 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-28748634

RESUMEN

Increasing parity and duration of combined oral contraceptive (COC) use provide substantial protection against ovarian carcinoma (cancer). There are limited data on the impact of the age of the births or age of COC use on reducing ovarian cancer risk. Here, we examined the effects of age at first and last births and age at use of COCs using data from studies conducted in Los Angeles County, California, USA (1,632 cases, 2,340 controls). After adjusting for the number of births, every 5 years that a first birth was delayed reduced the risk of ovarian cancer by 13% (95% CI 5-21%; p = 0.003); a first birth after age 35 was associated with a 47% lower risk than a first birth before age 25. COC use before age 35 was associated with greater protection per year of use than COC use at older ages. Considering previously published results as well as the results presented here, increasing parity and a later age at births are both important protective factors against ovarian cancer and the protection extends over 30 or more years from last birth. Current models of the etiology of ovarian cancer do not encompass an effect of late age at births. Our result of an attenuation of the protective effect with COC use after around age 35 needs further investigation as it has not been seen in all studies.


Asunto(s)
Anticonceptivos Orales/administración & dosificación , Edad Materna , Neoplasias Ováricas/epidemiología , Paridad , Adulto , Edad de Inicio , California/epidemiología , Femenino , Humanos , Embarazo , Factores de Riesgo , Encuestas y Cuestionarios , Adulto Joven
5.
Gynecol Oncol ; 139(2): 236-41, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26404183

RESUMEN

OBJECTIVE: Ovarian clear cell carcinomas (OCCCs) are rare, and uncertainty exists as to the optimal treatment paradigm and validity of the FIGO staging system, especially in early-stage disease. METHODS: We performed a retrospective cohort study of all OCCC patients diagnosed and treated at Memorial Sloan Kettering Cancer Center between January 1996 and December 2013. Progression-free survival (PFS) and overall survival (OS) were calculated by stage and race, and comparisons were made using the log-rank test. Statistical significance was set at p<0.05. Type and duration of treatment were also recorded. RESULTS: There were 177 evaluable patients. The majority of patients were stage I at diagnosis (110/177, 62.2%). Of these, 60/110 (54.6%) were stage IA, 31/110 (28.2%) were stage IC on the basis of rupture-only, and 19/110 (17.3%) were stage IC on the basis of surface involvement and/or positive cytology of ascites or washings. Patients with stage IA and IC based on rupture-only had similar PFS/OS outcomes. Patients with stage IC based on surface involvement and/or positive cytology had a statistically significant decrement in PFS/OS. Stage was an important indicator of PFS/OS, while race was not. CONCLUSIONS: OCCC often presents in early stage. Women with stage IA OCCC have excellent prognosis, and future studies should explore whether they benefit from adjuvant chemotherapy. Women with IC OCCC need further staging clarification, as surgical rupture alone affords better prognosis than surface involvement and/or positive cytology. Women with advanced OCCC have poor survival and are often chemotherapy resistant/refractory. New treatment paradigms are needed.


Asunto(s)
Adenocarcinoma de Células Claras/patología , Neoplasias Ováricas/patología , Ovario/lesiones , Adenocarcinoma de Células Claras/mortalidad , Adenocarcinoma de Células Claras/terapia , Adulto , Anciano , Anciano de 80 o más Años , Quimioterapia Adyuvante , Estudios de Cohortes , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Persona de Mediana Edad , Terapia Neoadyuvante , Estadificación de Neoplasias , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/terapia , Ovariectomía/efectos adversos , Pronóstico , Estudios Retrospectivos , Rotura/etiología , Tasa de Supervivencia
6.
Gynecol Oncol ; 136(3): 505-11, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25546114

RESUMEN

OBJECTIVE: Granulosa cell tumors (GCTs) are rare, and the role of chemotherapy in their management is not clearly defined. METHODS: We performed a retrospective cohort study of GCT patients diagnosed from January 1996 through June 2013 at the Memorial Sloan Kettering Cancer Center, comparing those who received adjuvant chemotherapy to those who did not. Differences between groups were assessed using the log-rank test. Statistical significance was set at p<0.05. RESULTS: Of 118 patients, 10 (8%) received adjuvant chemotherapy (1 [1%] of 103 stage I and 9 [60%] of 15 stage II-IV patients). Thirty-two patients (27%) experienced disease recurrence. Four patients had residual disease after initial surgery, and all received adjuvant chemotherapy; each recurred within 24.3 months (median PFS, 8.2 months). The time to first recurrence was longer in patients who did not receive adjuvant chemotherapy. For patients with recurrent disease, receiving chemotherapy after surgery for first recurrence did not seem to improve time to second recurrence versus surgery alone (HR 0.98; p=0.965). Additionally, 12 patients (10%) had a previous diagnosis of breast cancer-an incidence rate 3.22 times higher than Surveillance, Epidemiology, and End Results (SEER) data predicts (p<0.001). CONCLUSIONS: Although the numbers were small, in this analysis chemotherapy was not found to improve the recurrence-free interval of patients with GCTs, a finding that requires prospective validation. Residual disease after surgery was associated with poor prognosis. Finally, there was a significantly higher than expected incidence of antecedent breast cancer in this population, an association that deserves further exploration.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Tumor de Células de la Granulosa/tratamiento farmacológico , Recurrencia Local de Neoplasia/prevención & control , Neoplasias Ováricas/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/administración & dosificación , Quimioterapia Adyuvante , Estudios de Cohortes , Supervivencia sin Enfermedad , Femenino , Tumor de Células de la Granulosa/mortalidad , Tumor de Células de la Granulosa/patología , Tumor de Células de la Granulosa/cirugía , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Estadificación de Neoplasias , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/patología , Neoplasias Ováricas/cirugía , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento
7.
Cancer Epidemiol Biomarkers Prev ; 31(9): 1823-1829, 2022 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-35700017

RESUMEN

BACKGROUND: The objectives of this study were (i) to explore whether differences in cell proliferation may help explain why most high-grade serous ovarian cancers (HGSOC) arise in the fallopian tube fimbriae (FTF) rather than in ovarian cortical inclusion cysts (CIC); (ii) to compare premenopausal and postmenopausal FTF proliferation as a reason why the age incidence of HGSOC increases at a slower rate after menopause; and (iii) to compare FTF proliferation in cycling women and women using the levonorgestrel intrauterine contraceptive system (Lng-IUS) to see whether proliferation on the Lng-IUS was lower. METHODS: We studied 60 women undergoing a salpingo-oophorectomy. We used Ki67, paired-box gene 8 (PAX8, Müllerian marker), and calretinin (mesothelial marker) to study FTF and CIC proliferation. RESULTS: FTF Ki67%+ was greater in the follicular than in the luteal phase (4.9% vs. 1.5%; P = 0.003); postmenopausal Ki67%+ was 1.7%. Ki67%+ in PAX8 negative (PAX8-) CICs was extremely low. Proliferation in PAX8+ CICs did not vary by menstrual phase or menopausal status. Follicular Ki67%+ was 2.6-fold higher in FTF than PAX8+ CICs. FTF Ki67%+ from 10 women using the Lng-IUS was not lower than in cycling women. CONCLUSIONS: Overall FTF Ki67%+ is greater than overall CIC Ki67%+. Overall FTF Ki67%+ in postmenopausal women is lower than in premenopausal women. The Lng-IUS is not associated with lower FTF Ki67%+. IMPACT: Ki67%+ provides an explanation of the preponderance of FTF-derived HGSOCs, and of the slower increase of HGSOCs after menopause. The Lng-IUS may not be associated with a protective effect against HGSOCs.


Asunto(s)
Quistes , Dispositivos Intrauterinos Medicados , Proliferación Celular , Anticonceptivos , Trompas Uterinas , Femenino , Humanos , Antígeno Ki-67 , Levonorgestrel/farmacología , Ciclo Menstrual
8.
JAMA Oncol ; 2(11): 1434-1440, 2016 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-27367496

RESUMEN

IMPORTANCE: The link between BRCA mutations and uterine cancer is unclear. Therefore, although risk-reducing salpingo-oophorectomy (RRSO) is standard treatment among women with BRCA mutations (BRCA+ women), the role of concomitant hysterectomy is controversial. OBJECTIVE: To determine the risk for uterine cancer and distribution of specific histologic subtypes in BRCA+ women after RRSO without hysterectomy. DESIGN, SETTING, AND PARTICIPANTS: This multicenter prospective cohort study included 1083 women with a deleterious BRCA1 or BRCA2 mutation identified from January 1, 1995, to December 31, 2011, at 9 academic medical centers in the United States and the United Kingdom who underwent RRSO without a prior or concomitant hysterectomy. Of these, 627 participants were BRCA1+; 453, BRCA2+; and 3, both. Participants were prospectively followed up for a median 5.1 (interquartile range [IQR], 3.0-8.4) years after ascertainment, BRCA testing, or RRSO (whichever occurred last). Follow up data available through October 14, 2014, were included in the analyses. Censoring occurred at uterine cancer diagnosis, hysterectomy, last follow-up, or death. New cancers were categorized by histologic subtype, and available tumors were analyzed for loss of the wild-type BRCA gene and/or protein expression. MAIN OUTCOMES AND MEASURES: Incidence of uterine corpus cancer in BRCA+ women who underwent RRSO without hysterectomy compared with rates expected from the Surveillance, Epidemiology, and End Results database. RESULTS: Among the 1083 women women who underwent RRSO without hysterectomy at a median age 45.6 (IQR: 40.9 - 52.5), 8 incident uterine cancers were observed (4.3 expected; observed to expected [O:E] ratio, 1.9; 95% CI, 0.8-3.7; P = .09). No increased risk for endometrioid endometrial carcinoma or sarcoma was found after stratifying by subtype. Five serous and/or serous-like (serous/serous-like) endometrial carcinomas were observed (4 BRCA1+ and 1 BRCA2+) 7.2 to 12.9 years after RRSO (BRCA1: 0.18 expected [O:E ratio, 22.2; 95% CI, 6.1-56.9; P < .001]; BRCA2: 0.16 expected [O:E ratio, 6.4; 95% CI, 0.2-35.5; P = .15]). Tumor analyses confirmed loss of the wild-type BRCA1 gene and/or protein expression in all 3 available serous/serous-like BRCA1+ tumors. CONCLUSIONS AND RELEVANCE: Although the overall risk for uterine cancer after RRSO was not increased, the risk for serous/serous-like endometrial carcinoma was increased in BRCA1+ women. This risk should be considered when discussing the advantages and risks of hysterectomy at the time of RRSO in BRCA1+ women.


Asunto(s)
Genes BRCA1 , Genes BRCA2 , Salpingectomía , Neoplasias Uterinas/genética , Neoplasias Uterinas/prevención & control , Adulto , Femenino , Estudios de Seguimiento , Humanos , Histerectomía , Pérdida de Heterocigocidad , Persona de Mediana Edad , Mutación , Ovariectomía , Estudios Prospectivos , Riesgo , Neoplasias Uterinas/epidemiología
9.
Am J Surg Pathol ; 39(11): 1449-57, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26457350

RESUMEN

Gastric-type adenocarcinoma of the uterine cervix (GAS) is a rare variant of mucinous endocervical adenocarcinoma not etiologically associated with human papillomavirus (HPV) infection, with minimal deviation adenocarcinoma (MDA) at the well-differentiated end of the morphologic spectrum. These tumors are reported to have worse prognosis than usual HPV associated endocervical adenocarcinoma (UEA). A retrospective review of GAS was performed from the pathology databases of 3 institutions spanning 20 years. Stage, metastatic patterns, and overall survival were documented. Forty GAS cases were identified, with clinical follow-up data available for 38. The tumors were subclassified as MDA (n=13) and non-MDA GAS (n=27). Two patients were syndromic (1 Li-Fraumeni, 1 Peutz-Jeghers). At presentation, 59% were advanced stage (FIGO II to IV), 50% had lymph node metastases, 35% had ovarian involvement, 20% had abdominal disease, 39% had at least 1 site of metastasis at the time of initial surgery, and 12% of patients experienced distant recurrence. The metastatic sites included lymph nodes, adnexa, omentum, bowel, peritoneum, diaphragm, abdominal wall, bladder, vagina, appendix, and brain. Follow-up ranged from 1.4 to 136.0 months (mean, 33.9 mo); 20/38 (52.6%) had no evidence of disease, 3/38 (7.9%) were alive with disease, and 15/38 (39.5%) died of disease. Disease-specific survival at 5 years was 42% for GAS versus 91% for UEA. There were no survival differences between MDA and non-MDA GAS. GAS represents a distinct, biologically aggressive type of endocervical adenocarcinoma. The majority of patients present at advanced stage and pelvic, abdominal, and distant metastases are not uncommon.


Asunto(s)
Adenocarcinoma Mucinoso/secundario , Neoplasias del Cuello Uterino/patología , Adenocarcinoma Mucinoso/clasificación , Adenocarcinoma Mucinoso/mortalidad , Adenocarcinoma Mucinoso/terapia , Adulto , Anciano , Diferenciación Celular , Connecticut , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Humanos , Japón , Estimación de Kaplan-Meier , Metástasis Linfática , Persona de Mediana Edad , Estadificación de Neoplasias , Ciudad de Nueva York , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Neoplasias del Cuello Uterino/clasificación , Neoplasias del Cuello Uterino/mortalidad , Neoplasias del Cuello Uterino/terapia
10.
Methods Cell Biol ; 108: 93-116, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22325599

RESUMEN

Macro-autophagy is the intracellular stress-response pathway by which the cell packages portions of the cytosol for delivery into the lysosome. This "packaging" is carried out by the de novo formation of a new organelle called the autophagosome that grows and encapsulates cytosolic material for eventual lysosomal degradation. How autophagosomes form, including especially how the membrane expands and eventually closes upon itself is an area of intense study. One factor implicated in both membrane expansion and membrane fusion is the ubiquitin-like protein, Atg8. During autophagy, Atg8 becomes covalently bound to phosphatidylethanolamine (PE) on the pre-autophagosomal membrane and remains bound through the maturation process of the autophagosome. In this chapter, we discuss two approaches to the in vitro reconstitution of this lipidation reaction. We then describe methods to study Atg8-PE mediated membrane tethering and fusion, two functions implicated in Atg8's role in autophagosome maturation.


Asunto(s)
Membrana Celular/química , Proteínas Asociadas a Microtúbulos/química , Proteínas de Saccharomyces cerevisiae/química , Animales , Autofagia , Proteína 7 Relacionada con la Autofagia , Familia de las Proteínas 8 Relacionadas con la Autofagia , Proteínas Relacionadas con la Autofagia , Biocatálisis , Reactivos de Enlaces Cruzados/química , Microscopía por Crioelectrón , Humanos , Cinética , Luz , Liposomas/química , Maleimidas/química , Fusión de Membrana , Lípidos de la Membrana/química , Proteínas Asociadas a Microtúbulos/biosíntesis , Proteínas Asociadas a Microtúbulos/aislamiento & purificación , Modelos Biológicos , Nefelometría y Turbidimetría , Tamaño de la Partícula , Fagosomas/química , Fosfatidiletanolaminas/química , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Proteínas de Saccharomyces cerevisiae/biosíntesis , Proteínas de Saccharomyces cerevisiae/aislamiento & purificación , Dispersión de Radiación , Enzimas Ubiquitina-Conjugadoras/química
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