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1.
Chem Soc Rev ; 53(17): 8546-8562, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39091219

RESUMEN

Silicon-stereogenic chiral organosilanes have found increasing applications in synthetic chemistry, medicinal chemistry, and materials science. In this context, various asymmetric catalytic methods have been established for the diverse synthesis of silicon-stereogenic silanes. In particular, asymmetric organocatalysis is emerging as an important and complementary synthetic tool for the enantioselective construction of silicon-stereocenters, along with the rapid development of chiral-metal catalyzed protocols. Its advent provides a powerful platform to achieve functionalized silicon-stereogenic organosilanes with structural diversity, and should lead to great development in chiral organosilicon chemistry. In this Tutorial Review, we highlight these latest achievements from two aspects: desymmetrizations of prochiral tetraorganosilanes and dynamic kinetic asymmetric transformations of racemic organosilanes by employing five organocatalytic activation modes. The advantages, limitations and synthetic value of each protocol, as well as the synthetic opportunities still open for further exploration, are also discussed.

2.
Int Arch Allergy Immunol ; 185(2): 182-189, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37980884

RESUMEN

INTRODUCTION: Comorbidities, such as gastroesophageal reflux disease (GERD), are common in patients with rhinosinusitis (RS). However, the link between RS and GERD has not been fully understood. This study aimed to investigate the causal relationship between GERD and acute (ARS) or chronic RS (CRS), providing references for the pathogenesis and management of RS. METHODS: The data were obtained from the Integrative Epidemiology Unit Open GWAS project and FinnGen. A total of 972,838 individuals were included. The inverse variance-weighted (IVW) method was applied to obtain the primary results of the study. Weighted median, MR-Egger, and mode-based methods were used to determine the robustness of the results. Cochran's Q statistic and MR-Egger method were applied to detect heterogeneity and pleiotrophy in instrumental variables (IVs). Other sensitivity analyses included MR-PRESSO and leave-one-out analysis. RESULTS: The MR study showed that GERD was associated with an increased risk of CRS (OR: 1.36, 95% CI: 1.18-1.57, p < 0.001). The results of other analysis methods were broadly consistent with the IVW estimate. No heterogeneity was detected by Cochran's Q test (p = 0.061) and MR-PRESSO (p = 0.074). No horizontal pleiotropy was shown in IVs (p = 0.700). GERD was also associated with an increased risk of ARS (OR: 1.31, 95% CI: 1.17-1.48, p < 0.001). Some analytical results were inconsistent with the IVW estimate. No heterogeneity and pleiotropy were observed. There was no sufficient evidence for a reverse causal effect of RS on GERD. CONCLUSION: Our study supported that GERD promoted the risk of CRS and may be a potential risk factor for ARS. This provides additional support for further investigation into the mechanisms of GERD on RS.


Asunto(s)
Reflujo Gastroesofágico , Rinosinusitis , Humanos , Análisis de la Aleatorización Mendeliana , Reflujo Gastroesofágico/complicaciones , Reflujo Gastroesofágico/epidemiología , Factores de Riesgo , Estudio de Asociación del Genoma Completo
3.
Ann Surg ; 277(4): 557-564, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36538627

RESUMEN

OBJECTIVE: To compare neoadjuvant chemotherapy (nCT) with CAPOX alone versus neoadjuvant chemoradiotherapy (nCRT) with capecitabine in locally advanced rectal cancer (LARC) with uninvolved mesorectal fascia (MRF). BACKGROUND DATA: nCRT is associated with higher surgical complications, worse long-term functional outcomes, and questionable survival benefits. Comparatively, nCT alone seems a promising alternative treatment in lower-risk LARC patients with uninvolved MRF. METHODS: Patients between June 2014 and October 2020 with LARC within 12 cm from the anal verge and uninvolved MRF were randomly assigned to nCT group with 4 cycles of CAPOX (Oxaliplatin 130 mg/m2 IV day 1 and Capecitabine 1000 mg/m2 twice daily for 14 d. Repeat every 3 wk) or nCRT group with Capecitabine 825 mg/m² twice daily administered orally and concurrently with radiation therapy (50 Gy/25 fractions) for 5 days per week. The primary end point is local-regional recurrence-free survival. Here we reported the results of secondary end points: histopathologic response, surgical events, and toxicity. RESULTS: Of the 663 initially enrolled patients, 589 received the allocated treatment (nCT, n=300; nCRT, n=289). Pathologic complete response rate was 11.0% (95% CI, 7.8-15.3%) in the nCT arm and 13.8% (95% CI, 10.1-18.5%) in the nCRT arm ( P =0.33). The downstaging (ypStage 0 to 1) rate was 40.8% (95% CI, 35.1-46.7%) in the nCT arm and 45.6% (95% CI, 39.7-51.7%) in the nCRT arm ( P =0.27). nCT was associated with lower perioperative distant metastases rate (0.7% vs. 3.1%, P =0.03) and preventive ileostomy rate (52.2% vs. 63.6%, P =0.008) compared with nCRT. Four patients in the nCT arm received salvage nCRT because of local disease progression after nCT. Two patients in the nCT arm and 5 in the nCRT arm achieved complete clinical response and were treated with a nonsurgical approach. Similar results were observed in subgroup analysis. CONCLUSIONS: nCT achieved similar pCR and downstaging rates with lower incidence of perioperative distant metastasis and preventive ileostomy compared with nCRT. CAPOX could be an effective alternative to neoadjuvant therapy in LARC with uninvolved MRF. Long-term follow-up is needed to confirm these results.


Asunto(s)
Terapia Neoadyuvante , Neoplasias del Recto , Humanos , Terapia Neoadyuvante/métodos , Resultado del Tratamiento , Capecitabina/uso terapéutico , Neoplasias del Recto/patología , Quimioradioterapia/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Estadificación de Neoplasias
4.
Oecologia ; 203(1-2): 193-204, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37823959

RESUMEN

Pollinators mediate interspecific and intraspecific plant-plant indirect interactions (competition vs. facilitation) via density-dependent processes, potentially shaping the dynamics of plant communities. However, it is still unclear which ecological drivers regulate density-dependent patterns, including scale, pollination niches (i.e., the main pollinator functional group) and floral attractiveness to pollinators. In this study, we conducted three-year field observations in Hengduan Mountains of southwest China. By gathering data for more than 100 animal-pollinated plant species, we quantified the effect (positive vs. negative) of conspecific and heterospecific flower density on pollination at two scales: plot-level (4 m2) and site-level (100-5000 m2). Then, we investigated how pollination niches and floral attractiveness to pollinators (estimated here as average per-flower visitation rates) modulated density-dependent pollination interactions. Pollinator visitation depended on conspecific and heterospecific flower density, with rare plants subjected to interspecific competition at the plot-level and interspecific facilitation at the site-level. Such interspecific competition at the plot-level was stronger for plants pollinated by diverse insects, while interspecific facilitation at the site-level was stronger for bee-pollinated plants. Moreover, we also found stronger positive conspecific density-dependence for plants with lower floral attractiveness at the site-level, meaning that they become more frequently visited when abundant. Our study indicates that the role of pollination in maintaining rare plants and plant diversity depends on the balance of density-dependent processes in species-rich communities. We show here that such balance is modulated by scale, pollination niches and floral attractiveness to pollinators, indicating the context-dependency of diversity maintenance mechanisms.


Asunto(s)
Plantas , Polinización , Abejas , Animales , Polinización/fisiología , Flores/fisiología , Insectos , China
5.
Breast Cancer Res Treat ; 181(3): 679-689, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32367460

RESUMEN

PURPOSE: Discordance between HER2 expression in tumor tissue (tHER2) and HER2 status on circulating tumor cells (cHER2) has been reported. It remains largely underexplored whether patients with tHER2-/cHER2+ can benefit from anti-HER2 targeted therapies. METHODS: cHER2 status was determined in 105 advanced-stage patients with tHER2- breast tumors. Association between cHER2 status and progression-free survival (PFS) was analyzed by univariate and multivariate Cox models and survival differences were compared by Kaplan-Meier method. RESULTS: Compared to the patients with low-risk cHER2 (cHER2+ < 2), those with high-risk cHER2 (cHER2+ ≥ 2) had shorter survival time and an increased risk for disease progression (hazard ratio [HR] 2.16, 95% confidence interval [CI] 1.20-3.88, P = 0.010). Among the patients with high-risk cHER2, those who received anti-HER2 targeted therapies had improved PFS compared with those who did not (HR 0.30, 95% CI 0.10-0.92, P = 0.035). In comparison, anti-HER2 targeted therapy did not affect PFS among those with low-risk cHER2 (HR 0.70, 95% CI 0.36-1.38, P = 0.306). Similar results were obtained after adjusting covariates. A longitudinal analysis of 67 patients with cHER2 detected during follow-ups found that those whose cHER2 status changed from high-risk at baseline to low-risk at first follow-up exhibited a significantly improved survival compared to those whose cHER2 remained high-risk (median PFS: 11.7 weeks vs. 2.0 weeks, log-rank P = 0.001). CONCLUSION: In advanced-stage breast cancer patients with tHER2- tumors, cHER2 status has the potential to guide the use of anti-HER2 targeted therapy in patients with high-risk cHER2.


Asunto(s)
Biomarcadores de Tumor/sangre , Neoplasias de la Mama/patología , Células Neoplásicas Circulantes/patología , Receptor ErbB-2/metabolismo , Neoplasias de la Mama/sangre , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Femenino , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , Células Neoplásicas Circulantes/metabolismo , Receptor ErbB-2/genética , Tasa de Supervivencia
6.
J Natl Compr Canc Netw ; 16(10): 1183-1192, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30323088

RESUMEN

Background: Use of chemotherapy in stage II colorectal cancer (CRC) is controversial because it improves survival only in some patients. We aimed to develop a statistical model using routine and readily available blood tests to predict the prognosis of patients with stage II CRC and to identify which patients are likely to benefit from chemotherapy. Methods: We divided 422 patients with stage II CRC into a training and a testing set. The association of routine laboratory variables and disease-free survival (DFS) was analyzed. A prognostic model was developed incorporating clinically relevant laboratory variables with demographic and tumor characteristics. A prognostic score was derived by calculating the sum of each variable weighted by its regression coefficient in the model. Model performance was evaluated by constructing receiver operating characteristic curves and calculating the area under the curve (AUC). Results: Significant associations were seen between 5 laboratory variables and patient DFS in univariate analyses. After stepwise selection, 3 variables (carcinoembryonic antigen, hemoglobin, creatinine) were retained in the multivariate model with an AUC of 0.75. Compared with patients with a low prognostic score, those with a medium and high prognostic score had a 1.99- and 4.78-fold increased risk of recurrence, respectively. The results from the training set were validated in the testing set. Moreover, chemotherapy significantly improved DFS in high-risk patients, but not in low- and medium-risk patients. Conclusions: A routine laboratory variable-based model may help predict DFS of patients with stage II CRC and identify high-risk patients more likely to benefit from chemotherapy.


Asunto(s)
Biomarcadores de Tumor/sangre , Neoplasias Colorrectales/terapia , Modelos Biológicos , Recurrencia Local de Neoplasia/diagnóstico , Factores de Edad , Anciano , Quimioterapia Adyuvante/métodos , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Recurrencia Local de Neoplasia/sangre , Recurrencia Local de Neoplasia/prevención & control , Estadificación de Neoplasias , Selección de Paciente , Valor Predictivo de las Pruebas , Pronóstico , Curva ROC , Estudios Retrospectivos , Medición de Riesgo/métodos
7.
Carcinogenesis ; 38(4): 439-446, 2017 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-28334112

RESUMEN

Prospective and longitudinal epidemiological evidence is needed to assess the association between telomere length and risk of hepatocellular carcinoma (HCC). In 323 cancer-free Korean-American HBV patients with 1-year exclusion window (followed for >1 year and did not develop HCC within 1 year), we measured the relative telomere length (RTL) in baseline serum DNAs and conducted extensive prospective and longitudinal analyses to assess RTL-HCC relationship. We found that long baseline RTL conferred an increased HCC risk compared to short RTL [hazard ratio (HR) = 4.93, P = 0.0005). The association remained prominent when the analysis was restricted to patients with a more stringent 5-year exclusion window (HR = 7.51, P = 0.012), indicating that the association was unlikely due to including undetected HCC patients in the cohort, thus minimizing the reverse-causation limitation in most retrospective studies. Adding baseline RTL to demographic variables increased the discrimination accuracy of the time-dependent receiver operating characteristic analysis from 0.769 to 0.868 (P = 1.0 × 10-5). In a nested longitudinal subcohort of 16 matched cases-control pairs, using a mixed effects model, we observed a trend of increased RTL in cases and decreased RTL in controls along 5 years of follow-up, with a significant interaction of case/control status with time (P for interaction=0.002) and confirmed the association between long RTL and HCC risk [odds ratio [OR] = 3.63, P = 0.016]. In summary, serum DNA RTL may be a novel non-invasive prospective marker of HBV-related HCC. Independent studies are necessary to validate and generalize this finding in diverse populations and assess the clinical applicability of RTL in HCC prediction.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma Hepatocelular/genética , ADN/genética , Hepatitis B Crónica/genética , Neoplasias Hepáticas/genética , Telómero/genética , Carcinoma Hepatocelular/virología , Estudios de Casos y Controles , Femenino , Virus de la Hepatitis B , Humanos , Neoplasias Hepáticas/virología , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Curva ROC , Estudios Retrospectivos , Factores de Riesgo
8.
Gastroenterology ; 150(5): 1135-1146, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26836586

RESUMEN

BACKGROUND & AIMS: We evaluated differences in treatment of black vs white patients with colon cancer and assessed their effects on survival, based on cancer stage. METHODS: We collected data from the Surveillance, Epidemiology, and End Results-Medicare database and identified 6190 black and 61,951 white patients with colon cancer diagnosed from 1998 through 2009 and followed up through 2011. Three sets of 6190 white patients were matched sequentially, using a minimum distance strategy, to the same set of 6190 black patients based on demographic (age; sex; diagnosis year; and Surveillance, Epidemiology, and End Results registry), tumor presentation (demographic plus comorbidities, tumor stage, grade, and size), and treatment (presentation plus therapies) variables. We conducted sensitivity analyses to explore the effects of socioeconomic status in a subcohort that included 2000 randomly selected black patients. Racial differences in treatment were assessed using a logistic regression model; their effects on racial survival disparity were evaluated using the Kaplan-Meier method and the Cox proportional hazards model. RESULTS: After patients were matched for demographic variables, the absolute 5-year difference in survival between black and white patients was 8.3% (white, 59.2% 5-y survival; blacks, 50.9% 5-y survival) (P < .0001); this value decreased significantly, to 5.0% (P < .0001), after patients were matched for tumor presentation, and decreased to 4.9% (P < .0001) when patients were matched for treatment. Differences in treatment therefore accounted for 0.1% of the 8.3% difference in survival between black and white patients. After patients were matched for tumor presentation, racial disparities were observed in almost all types of treatment; the disparities were most prominent for patients with advanced-stage cancer (stages III or IV, up to an 11.1% difference) vs early stage cancer (stages I or II, up to a 4.3% difference). After patients were matched for treatment, there was a greater reduction in disparity for black vs white patients with advanced-stage compared with early-stage cancer. In sensitivity analyses, the 5-year racial survival disparity was 7.7% after demographic match, which was less than the 8.3% observed in the complete cohort. This reduction likely was owing to the differences between the subcohort and the complete cohort in those variables that were not included in the demographic match. This value was reduced to 6.5% (P = .0001) after socioeconomic status was included in the demographic match. The difference decreased significantly to 2.8% (P = .090) after tumor presentation match, but was not reduced further after treatment match. CONCLUSIONS: We observed significant disparities in treatment and survival of black vs white patients with colon cancer. The disparity in survival appears to have been affected more strongly by tumor presentation at diagnosis than treatment. The effects of treatment differences on disparities in survival were greater for patients with advanced-stage vs early-stage cancer.


Asunto(s)
Negro o Afroamericano , Neoplasias del Colon/etnología , Neoplasias del Colon/terapia , Disparidades en el Estado de Salud , Disparidades en Atención de Salud/etnología , Población Blanca , Anciano , Neoplasias del Colon/mortalidad , Neoplasias del Colon/patología , Comorbilidad , Femenino , Humanos , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Clasificación del Tumor , Estadificación de Neoplasias , Modelos de Riesgos Proporcionales , Factores de Riesgo , Programa de VERF , Factores Socioeconómicos , Factores de Tiempo , Resultado del Tratamiento , Carga Tumoral , Estados Unidos/epidemiología
9.
Breast Cancer Res Treat ; 165(3): 733-741, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28687903

RESUMEN

PURPOSE: Circulating cancer associated macrophage-like cells (CAMLs) have been detected in the peripheral blood of patients with solid tumors including breast cancer. However, the prognostic relevance of CAMLs in metastatic breast cancer (MBC) has not been evaluated. In the present study, we aimed to measure CAMLs and circulating tumor cells (CTCs) at baseline and examine their prognostic value in patients with MBC. METHODS: Peripheral blood samples from 127 MBC patients were collected at baseline before starting a new treatment. The detection and enumeration of CAMLs and CTCs in 7.5 ml whole blood were performed using the CellSearch™ system. The associations of CAMLs and CTCs with the progression-free survival (PFS) and overall survival (OS) in the patients were evaluated using Kaplan-Meier curves and Cox proportional hazards modeling. RESULTS: Among 127 MBC patients, 21 (16.5%) were detected with CAMLs and 38 (29.9%) had elevated CTCs (≥5 CTCs/7.5 ml). Patients with CAMLs at baseline had worse PFS and OS with an adjusted hazard ratio (HR) of 1.75 (95% CI 1.03-2.98, P = 0.0374) and 3.75 (95% CI 1.52-9.26, P = 0.0042), compared to patients without CAMLs. Compared with patients with <5 CTCs and without CAMLs, patients with <5 CTCs and with CAMLs, with ≥5 CTCs but without CAMLs, or with ≥5 CTCs and with CAMLs, had an increasing trend of risk of disease progression (HR = 0.84, 3.42 and 4.04 respectively, P for trend <0.0001) and death (HR = 2.66, 6.14, and 9.13, respectively, P for trend <0.0001). CONCLUSION: Baseline enumeration of individual CAMLs is an independent indicator for MBC patients' survival. Evaluation of CAMLs in peripheral blood might provide a potential biomarker with additional prognostic values over CTC enumeration alone in MBC patients.


Asunto(s)
Biomarcadores de Tumor , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Macrófagos/patología , Adulto , Anciano , Neoplasias de la Mama/terapia , Recuento de Células , Femenino , Humanos , Estimación de Kaplan-Meier , Macrófagos/metabolismo , Persona de Mediana Edad , Metástasis de la Neoplasia , Estadificación de Neoplasias , Células Neoplásicas Circulantes/patología , Evaluación del Resultado de la Atención al Paciente , Pronóstico , Modelos de Riesgos Proporcionales
10.
Breast Cancer Res Treat ; 161(1): 83-94, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27771841

RESUMEN

PURPOSE: Circulating tumor cell (CTC) is a well-established prognosis predictor for metastatic breast cancer (MBC), and CTC-cluster exhibits significantly higher metastasis-promoting capability than individual CTCs. Because measurement of CTCs and CTC-clusters at a single time point may underestimate their prognostic values, we aimed to analyze longitudinally collected CTCs and CTC-clusters in MBC prognostication. METHODS: CTCs and CTC-clusters were enumerated in 370 longitudinally collected blood samples from 128 MBC patients. The associations between baseline, first follow-up, and longitudinal enumerations of CTCs and CTC-clusters with patient progression-free survival (PFS) and overall survival (OS) were analyzed using Cox proportional hazards models. RESULTS: CTC and CTC-cluster counts at both baseline and first follow-up were significantly associated with patient PFS and OS. Time-dependent analysis of longitudinally collected samples confirmed the significantly unfavorable PFS and OS in patients with ≥5 CTCs, and further demonstrated the independent prognostic values by CTC-clusters compared to CTC-enumeration alone. Longitudinal analyses also identified a link between the size of CTC-clusters and patient OS: compared to the patients without any CTC, those with 2-cell CTC-clusters and ≥3-cell CTC-clusters had a hazard ratio (HR) of 7.96 [95 % confidence level (CI) 2.00-31.61, P = 0.003] and 14.50 (3.98-52.80, P < 0.001), respectively. CONCLUSIONS: In this novel time-dependent analysis of longitudinally collected CTCs and CTC-clusters, we showed that CTC-clusters added additional prognostic values to CTC enumeration alone, and a larger-size CTC-cluster conferred a higher risk of death in MBC patients.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/mortalidad , Células Neoplásicas Circulantes/patología , Adulto , Anciano , Neoplasias de la Mama/terapia , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Pronóstico , Análisis de Supervivencia
11.
Ann Bot ; 119(6): 1053-1059, 2017 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-28158409

RESUMEN

Background and Aims: It has been suggested that the dynamics of nectar replenishment could differ for flowers after being nectar robbed or visited legitimately, but further experimental work is needed to investigate this hypothesis. This study aimed to assess the role of nectar replenishment in mediating the effects of nectar robbing on pollinator behaviour and plant reproduction. Methods: Plant-robber-pollinator interactions in an alpine plant, Salvia przewalskii , were studied. It is pollinated by long-tongued Bombus religiosus and short-tongued B. friseanus , but robbed by B. friseanus . Nectar production rates for flowers after they were either robbed or legitimately visited were compared, and three levels of nectar robbing were created to detect the effects of nectar robbing on pollinator behaviour and plant reproduction. Key Results: Nectar replenishment did not differ between flowers that had been robbed or legitimately visited. Neither fruit set nor seed set was significantly affected by nectar robbing. In addition, nectar robbing did not significantly affect visitation rate, flowers visited within a plant per foraging bout, or flower handling time of the legitimate pollinators. However, a tendency for a decrease in relative abundance of the pollinator B. religiosus with an increase of nectar robbing was found. Conclusions: Nectar robbing did not affect female reproductive success because nectar replenishment ensures that pollinators maintain their visiting activity to nectar-robbed flowers. Nectar replenishment might be a defence mechanism against nectar robbing to enhance reproductive fitness by maintaining attractiveness to pollinators. Further studies are needed to reveal the potential for interference competition among bumble bees foraging as robbers and legitimate visitors, and to investigate variation of nectar robbing in communities with different bumble bee species composition.


Asunto(s)
Abejas/fisiología , Conducta Alimentaria , Néctar de las Plantas/metabolismo , Polinización , Salvia/fisiología , Animales , China , Cadena Alimentaria , Reproducción
12.
Yi Chuan ; 39(5): 368-376, 2017 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-28487269

RESUMEN

The retrotransposon LINE-1 is the largest transposon family of humans with an estimated 500 000 copies representing 17% of the human genome. Meanwhile, it is also the sole autonomous transposon in humans. The reverse transcriptase encoded by LINE-1 is the key component required for its transposition process. Recent evidence suggests that the LINE-1-encoded reverse transcriptase is involved in many important physiological and pathological processes including tumorigenesis. The inhibition of LINE-1-encoded reverse transcriptase inhibits tumor progression, restores cancer cell differentiation and reprograms global transcription profiles. In this review, we summarize newly emerged evidence, and conclude that the LINE-1-encoded reverse transcriptase influences tumorigenesis by shaping the non-coding RNA transcriptomic profile. We hope that this review may shed light on clinical diagnosis and drug development against cancer.


Asunto(s)
Carcinogénesis/genética , Elementos de Nucleótido Esparcido Largo/genética , ADN Polimerasa Dirigida por ARN/genética , Humanos , Neoplasias/genética , ARN no Traducido/genética , Transcriptoma/genética
13.
Oncologist ; 21(11): 1296-1297e, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-28178640

RESUMEN

LESSONS LEARNED: Patients with metastatic castration-resistant prostate cancer did not tolerate the combination of alisertib with abiraterone and prednisone.There was no clear signal indicating that adding alisertib might be beneficial for those patients progressing on abiraterone. BACKGROUND: We hypothesized that Aurora A kinase (AK) contributes to castrate resistance in prostate cancer (PCa) and that inhibiting AK with alisertib can resensitize PCa cells to androgen receptor (AR) inhibitor abiraterone. METHODS: This was a phase I/II trial to determine the safety and efficacy of alisertib when given in combination with abiraterone plus prednisone (AP). Metastatic castration-resistant prostate cancer (mCRPC) patients were treated with dose escalation (alisertib at 30, 40, and 50 mg orally b.i.d., days 1-7 every 21 days) per standard 3+3 design. RESULTS: Nine of 43 planned subjects were enrolled. The maximum tolerated dose (MTD) was not reached, and the dose-limiting toxicities (DLTs) included neutropenic fever (1 of 9), neutropenia (1 of 9), fatigue with memory impairment (1 of 9), and diarrhea/mucositis (1 of 9). No prostate-specific antigen (PSA) decrease or circulating tumor cell (CTC) changes were observed during the study. Pharmacodynamically, adding alisertib did not affect total testosterone or dehydroepiandrosterone (DHEA) levels. There was some change in neuroendocrine markers after therapy. Mean duration on study was 2.5 months. The trial was terminated early. CONCLUSION: A tolerable dose of alisertib in combination with AP in mCRPC was not established in this study. There was no clear signal indicating that alisertib might be beneficial for patients with mCRPC progressing on abiraterone.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Aurora Quinasa A/antagonistas & inhibidores , Azepinas/administración & dosificación , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Pirimidinas/administración & dosificación , Anciano , Anciano de 80 o más Años , Androstenos/administración & dosificación , Androstenos/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Azepinas/efectos adversos , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Metástasis de la Neoplasia , Prednisona/administración & dosificación , Prednisona/efectos adversos , Pirimidinas/efectos adversos , Testosterona/sangre
14.
Int J Mol Sci ; 17(10)2016 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-27706044

RESUMEN

The availability of blood-based diagnostic testing using a non-invasive technique holds promise for real-time monitoring of disease progression and treatment selection. Circulating tumor cells (CTCs) have been used as a prognostic biomarker for the metastatic breast cancer (MBC). The molecular characterization of CTCs is fundamental to the phenotypic identification of malignant cells and description of the relevant genetic alterations that may change according to disease progression and therapy resistance. However, the molecular characterization of CTCs remains a challenge because of the rarity and heterogeneity of CTCs and technological difficulties in the enrichment, isolation and molecular characterization of CTCs. In this pilot study, we evaluated circulating tumor associated cells in one blood draw by size exclusion technology and cytological analysis. Among 30 prospectively enrolled MBC patients, CTCs, circulating tumor cell clusters (CTC clusters), CTCs of epithelial-mesenchymal transition (EMT) and cancer associated macrophage-like cells (CAMLs) were detected and analyzed. For molecular characterization of CTCs, size-exclusion method for CTC enrichment was tested in combination with DEPArray™ technology, which allows the recovery of single CTCs or pools of CTCs as a pure CTC sample for mutation analysis. Genomic mutations of TP53 and ESR1 were analyzed by targeted sequencing on isolated 7 CTCs from a patient with MBC. The results of genomic analysis showed heterozygous TP53 R248W mutation from one single CTC and pools of three CTCs, and homozygous TP53 R248W mutation from one single CTC and pools of two CTCs. Wild-type ESR1 was detected in the same isolated CTCs. The results of this study reveal that size-exclusion method can be used to enrich and identify circulating tumor associated cells, and enriched CTCs were characterized for genetic alterations in MBC patients, respectively.


Asunto(s)
Neoplasias de la Mama/patología , Células Neoplásicas Circulantes/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/metabolismo , Análisis Mutacional de ADN , Transición Epitelial-Mesenquimal , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismo , Femenino , Humanos , Microscopía Fluorescente , Mutación , Metástasis de la Neoplasia , Estadificación de Neoplasias , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
15.
Int J Cancer ; 136(2): 382-91, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-24866905

RESUMEN

Cancer patients undergo routine clinical monitoring with an array of blood tests that may carry long-term prognostic information. We aimed to develop a new prognostic model predicting survival for patients with advanced non-small cell lung cancer (NSCLC), based on laboratory tests commonly performed in clinical practice. A cohort of 1,161 stage IIIB or IV NSCLC patients was divided into training (n = 773) and testing (n = 388) cohorts. We analyzed the associations of 32 commonly tested laboratory variables with patient survival in the training cohort. We developed a model based on those significant laboratory variables, together with important clinical variables. The model was then evaluated in the testing cohort. Five variables, including albumin, total protein, alkaline phosphatase, blood urea nitrogen and international normalized ratio, were significantly associated with patient survival after stepwise selection. A model incorporating these variables classified patients into low-, medium- and high-risk groups with median survival of 16.9, 7.2 and 2.1 months, respectively (p < 0.0001). Compared with low-risk group, patients in the medium- and high-risk groups had a significantly higher risk of death at 1 year, with hazard ratio (HR) of 1.95 (95% CI 1.62-2.36) and 5.22 (4.30-6.34), respectively. These results were validated in the testing cohort. Overall, we developed a prognostic model relying entirely on readily available variables, with similar predictive power to those which depend on more specialized and expensive molecular assays. Further study is necessary to validate and further refine this model, and compare its performance to models based on more specialized and expensive testing.


Asunto(s)
Adenocarcinoma/mortalidad , Carcinoma de Células Grandes/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Células Escamosas/mortalidad , Pruebas Diagnósticas de Rutina , Neoplasias Pulmonares/mortalidad , Modelos Estadísticos , Adenocarcinoma/patología , Adenocarcinoma/terapia , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Grandes/patología , Carcinoma de Células Grandes/terapia , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/terapia , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/terapia , Estudios de Cohortes , Interpretación Estadística de Datos , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/terapia , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , Tasa de Supervivencia
16.
Breast Cancer Res Treat ; 153(2): 407-16, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26264468

RESUMEN

Current clinical guidelines state that the use of erythropoiesis-stimulating agents (ESAs) may be considered to treat chemotherapy-induced anemia in the non-curative setting to alleviate anemia-related symptoms. However, no convincing survival benefit has been demonstrated to support the use of ESAs in these patients. Using the comprehensive data collected in the National Cancer Institute (NCI)-surveillance epidemiology and end results (SEER) and Medicare-linked database, we analyzed the effect of ESA use on the short-term (18-month) and long-term (60-month) survival rates of chemotherapy-treated metastatic breast cancer patients. Confounding variables were adjusted using a propensity score approach. We also analyzed the effects of ESA on the survival of patients receiving trastuzumab, a commonly prescribed targeted therapy agent in treating HER2-positive tumors. Metastatic breast cancer patients who received ESA treatment exhibited similar 60-month survival rate to those without ESA treatment (22.8 vs. 24.9%, p = 0.8). ESA-treated patients had a trend toward better 18-month survival [crude hazard ratio (HR) 0.86, 95% confidence intervals (CI) 0.68-1.09, p = 0.21]. This protective effect during the first 18 months of chemotherapy became marginally significant after adjusting for the propensity of receiving ESAs (HR 0.80, 95% CI 0.63-1.01, p = 0.070). An interaction effect between ESA and trastuzumab on patient survival was noticeable but not statistically significant. ESAs did not negatively affect the long-term survival of metastatic breast cancer patients. Moreover, ESAs improved patients' survival during the first 18 months of chemotherapy treatment. These findings endorse the current clinical guideline. Given the short survival of these patients, the potential short-term beneficial effects of ESAs are clinically meaningful.


Asunto(s)
Anemia/tratamiento farmacológico , Anemia/etiología , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/mortalidad , Hematínicos/uso terapéutico , Anciano , Anciano de 80 o más Años , Anemia/mortalidad , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Comorbilidad , Interacciones Farmacológicas , Femenino , Humanos , Persona de Mediana Edad , Clasificación del Tumor , Metástasis de la Neoplasia , Oportunidad Relativa , Vigilancia de la Población , Factores de Riesgo , Programa de VERF , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos/epidemiología
17.
Breast Cancer Res Treat ; 154(3): 563-71, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26573830

RESUMEN

The enumeration of circulating tumor cells (CTCs) provides important prognostic values in patients with metastatic breast cancer. Recent studies indicate that individual CTCs form clusters and these CTC-clusters play an important role in tumor metastasis. We aimed to assess whether quantification of CTC-clusters provides additional prognostic value over quantification of individual CTCs alone. In 115 prospectively enrolled advanced-stage (III and IV) breast cancer patients, CTCs and CTC-clusters were counted in 7.5 ml whole blood using the CellSearch system at baseline before first-line therapy. The individual and joint effects of CTC and CTC cluster counts on patients' progression-free survival (PFS) were analyzed using Cox proportional hazards modeling. Of the 115 patients, 36 (31.3 %) had elevated baseline CTCs (≥5 CTCs/7.5 ml) and 20 (17.4 %) had CTC-clusters (≥2 CTCs/7.5 ml). Patients with elevated CTCs and CTC-clusters both had worse PFS with a hazard ratio (HR) of 2.76 [95 % confidence interval (CI) 1.57-4.86, P log-rank = 0.0005] and 2.83 (1.48-5.39, P log-rank = 0.001), respectively. In joint analysis, compared with patients with <5 CTCs and without CTC-clusters, patients with elevated CTCs but without clusters, and patients with elevated CTCs and with clusters, had an increasing trend of progression risk, with an HR of 2.21 (1.02-4.78) and 3.32 (1.68-6.55), respectively (P log-rank = 0.0006, P trend = 0.0002). The additional prognostic value of CTC-clusters appeared to be more pronounced in patients with inflammatory breast cancer (IBC), the most aggressive form of breast cancer with the poorest survival. Baseline counts of both individual CTCs and CTC-clusters were associated with PFS in advanced-stage breast cancer patients. CTC-clusters might provide additional prognostic value compared with CTC enumeration alone, in patients with elevated CTCs.


Asunto(s)
Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Células Neoplásicas Circulantes/patología , Anciano , Biomarcadores de Tumor/sangre , Supervivencia sin Enfermedad , Femenino , Humanos , Neoplasias Inflamatorias de la Mama/mortalidad , Neoplasias Inflamatorias de la Mama/patología , Estimación de Kaplan-Meier , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos
18.
J Membr Biol ; 248(1): 39-46, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25249020

RESUMEN

Herein, the biological effects of heavy rare earth ion Er(III) on rice mitochondria were comprehensively investigated mainly by spectroscopic methods. The experimental results demonstrated that Er(III) could lead to the swelling of rice mitochondria, collapse of mitochondrial transmembrane potential, decrease of membrane fluidity, promotion of H(+) permeability and suppression of K(+) permeability. These further indicated that Er(III) could induce the mitochondrial permeability transition (MPT) and the dysfunction of rice mitochondria. The ultra-structure change of mitochondria observed by transmission electron microscopy (TEM) also proved that Er(III) induced MPT. Moreover, the testing results of the protective effect of four different agents on mitochondrial swelling implied that the thiol chelation on the mitochondrial inner membrane was the main reason that caused the MPT.


Asunto(s)
Erbio/farmacología , Mitocondrias/metabolismo , Oryza/metabolismo , Permeabilidad de la Membrana Celular/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Microscopía Electrónica de Transmisión , Mitocondrias/efectos de los fármacos , Oryza/efectos de los fármacos
19.
J Membr Biol ; 248(6): 1159-65, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26305923

RESUMEN

Ytterbium (Yb), a widely used rare earth element, is treated as highly toxic to human being and adverseness to plant. Mitochondria play a significant role in plant growth and development, and are proposed as a potential target for ytterbium toxicity. In this paper, the biological effect of Yb(3+) on isolated rice mitochondria was investigated. We found that Yb(3+) with high concentrations (200 ~ 600 µM) not only induced mitochondrial membrane permeability transition (mtMPT), but also disturbed the mitochondrial ultrastructure. Moreover, Yb(3+) caused the respiratory chain damage, ROS formation, membrane potential decrease, and mitochondrial complex II activity reverse. The results above suggested that Yb(3+) with high concentrations could induce mitochondrial membrane dysfunction. These findings will support some valuable information to the safe application of Yb-based agents.


Asunto(s)
Membranas Mitocondriales/metabolismo , Oryza/efectos de los fármacos , Oryza/metabolismo , Iterbio/toxicidad , Transporte de Electrón/efectos de los fármacos , Complejo II de Transporte de Electrones/metabolismo , Fluidez de la Membrana/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/ultraestructura , Especies Reactivas de Oxígeno/metabolismo , Ácido Succínico/metabolismo
20.
Cancer Causes Control ; 26(1): 45-56, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25359303

RESUMEN

PURPOSE: A survival disparity of black versus white breast cancer patients has been extensively documented but not adequately explained. Blacks and whites also have significant differences in hematologic traits including hemoglobin (HGB). However, a link between survival disparity and hematologic differences has not been reported. We aimed to explore the effect of pre-treatment hematologic variables on this survival disparity. METHODS: We sequentially matched 443 black patients, using a minimum distance approach, to four different sets of 443 whites on demographics (age, year of diagnosis, smoking, and drinking status), tumor presentation (all demographic variables plus tumor stage, grade, and hormone receptor status), treatment (all presentation variables plus surgery, chemotherapy, radiation therapy, and hormone therapy), and presentation plus pre-treatment hematologic variables. Racial survival for each matched dataset was analyzed by Cox proportional hazards model. RESULTS: We found that white patients matched on demographic characteristics had more favorable survival than blacks [hazard ratio (HR) 0.57, 95 % confidence interval (CI) 0.42-0.77, p log-rank = 0.0002]. Presentation match diminished this disparity [HR 0.72 (0.54-0.95), p log-rank = 0.0199], which was not further reduced in treatment match [HR 0.73 (0.55-0.96), p log-rank = 0.0249]. However, the survival disparity was largely reduced when pre-treatment level of HGB or red blood cell distribution width was further matched in addition to presentation match [HR 0.83 (0.64-1.09), p log-rank = 0.1819 and HR 0.83 (0.64-1.09), p log-rank = 0.1760, respectively]. CONCLUSIONS: We found that in our patient population, differences in tumor presentation and certain pre-treatment hematologic traits, but not treatment, were associated with the survival disparity between black and white breast cancer patients.


Asunto(s)
Neoplasias de la Mama/mortalidad , Disparidades en el Estado de Salud , Anciano , Neoplasias de la Mama/etnología , Neoplasias de la Mama/patología , Etnicidad , Femenino , Humanos , Incidencia , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Análisis de Supervivencia , Estados Unidos/epidemiología
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