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Featured researches published by Koen De Geest.


Journal of Clinical Oncology | 2009

Evaluation of New Platinum-Based Treatment Regimens in Advanced-Stage Ovarian Cancer: A Phase III Trial of the Gynecologic Cancer InterGroup

Michael A. Bookman; Mark F. Brady; William P. McGuire; Peter Harper; David S. Alberts; Michael Friedlander; Nicoletta Colombo; Jeffrey M. Fowler; Peter A. Argenta; Koen De Geest; David G. Mutch; Robert A. Burger; Ann Marie Swart; Edward L. Trimble; Chrisann Accario-Winslow; Lawrence M. Roth

PURPOSE To determine if incorporation of an additional cytotoxic agent improves overall survival (OS) and progression-free survival (PFS) for women with advanced-stage epithelial ovarian carcinoma (EOC) and primary peritoneal carcinoma who receive carboplatin and paclitaxel. PATIENTS AND METHODS Women with stages III to IV disease were stratified by coordinating center, maximal diameter of residual tumor, and intent for interval cytoreduction and were then randomly assigned among five arms that incorporated gemcitabine, methoxypolyethylene glycosylated liposomal doxorubicin, or topotecan compared with carboplatin and paclitaxel. The primary end point was OS and was determined by pairwise comparison to the reference arm, with a 90% chance of detecting a true hazard ratio of 1.33 that limited type I error to 5% (two-tail) for the four comparisons. RESULTS Accrual exceeded 1,200 patients per year. An event-triggered interim analysis occurred after 272 events on the reference arm, and the study closed with 4,312 women enrolled. Arms were well balanced for demographic and prognostic factors, and 79% of patients completed eight cycles of therapy. There were no improvements in either PFS or OS associated with any experimental regimen. Survival analyses of groups defined by size of residual disease also failed to show experimental benefit in any subgroup. CONCLUSION Compared with standard paclitaxel and carboplatin, addition of a third cytotoxic agent provided no benefit in PFS or OS after optimal or suboptimal cytoreduction. Dual-stage, multiarm, phase III trials can efficiently evaluate multiple experimental regimens against a single reference arm. The development of new interventions beyond surgery and conventional platinum-based chemotherapy is required to additionally improve outcomes for women with advanced EOC.


Journal of the National Cancer Institute | 2008

Effect of Interleukin-8 Gene Silencing With Liposome-Encapsulated Small Interfering RNA on Ovarian Cancer Cell Growth

William M. Merritt; Yvonne G. Lin; Whitney A. Spannuth; Mavis S. Fletcher; Aparna A. Kamat; Liz Y. Han; Charles N. Landen; Nicholas B. Jennings; Koen De Geest; Robert R. Langley; Gabriel J. Villares; Angela Sanguino; Susan K. Lutgendorf; Gabriel Lopez-Berestein; Menashe Bar-Eli; Anil K. Sood

BACKGROUND Interleukin-8 (IL-8) is a proangiogenic cytokine that is overexpressed in many human cancers. We investigated the clinical and biologic significance of IL-8 in ovarian carcinoma using human samples and orthotopic mouse models. METHODS Tumor expression of IL-8 was assessed by immunohistochemistry among ovarian cancer patients (n = 102) with available clinical and survival data. We examined the effect of IL-8 gene silencing with small interfering RNAs incorporated into neutral liposomes (siRNA-DOPCs), alone and in combination with docetaxel, on in vivo tumor growth, angiogenesis (microvessel density), and tumor cell proliferation in mice (n = 10 per treatment group) bearing orthotopic taxane-sensitive (HeyA8 and SKOV3ip1) and taxane-resistant (SKOV3ip2.TR) ovarian tumors. All statistical tests were two-sided. RESULTS Of the 102 cancer specimens, 43 (42%) had high IL-8 expression and 59 (58%) had low or no IL-8 expression; high IL-8 expression was associated with advanced tumor stage (P = .019), high tumor grade (P = .031), and worse survival (median survival for patients with high vs low IL-8 expression: 1.62 vs 3.79 years; P < .001). Compared with empty liposomes, IL-8 siRNA-DOPC reduced the mean tumor weight by 32% (95% confidence interval [CI] = 14% to 50%; P = .03) and 52% (95% CI = 27% to 78%; P = .03) in the HeyA8 and SKOV3ip1 mouse models, respectively. In all three mouse models, treatment with IL-8 siRNA-DOPC plus the taxane docetaxel reduced tumor growth the most compared with empty liposomes (77% to 98% reduction in tumor growth; P < .01 for all). In the HeyA8 and SKOV3ip1 models, tumors from mice treated with IL-8 siRNA-DOPC alone had lower microvessel density than tumors from mice treated with empty liposomes (HeyA8: 34% lower, 95% CI = 32% to 36% lower [P = .002]; SKOV3ip1: 39% lower, 95% CI = 34% to 44% lower [P = .007]). Compared with empty liposomes, IL-8 siRNA-DOPC plus docetaxel reduced tumor cell proliferation by 35% (95% CI = 25% to 44%; P < .001) and 38% (95% CI = 28% to 48%; P < .001) in the HeyA8 and SKOV3ip1 models, respectively. CONCLUSIONS Increased IL-8 expression is associated with poor clinical outcome in human ovarian carcinoma, and IL-8 gene silencing decreases tumor growth through antiangiogenic mechanisms.


Journal of Clinical Oncology | 2005

Social Support, Psychological Distress, and Natural Killer Cell Activity in Ovarian Cancer

Susan K. Lutgendorf; Anil K. Sood; Barrie Anderson; Stephanie McGinn; Heena Maiseri; Minh Dao; Joel I. Sorosky; Koen De Geest; Justine M. Ritchie; David M. Lubaroff

PURPOSE Psychosocial stress has been related to impaired immunity in cancer patients. However, the extent to which these relationships exist in immune cells in the tumor microenvironment in humans has not been explored. We examined relationships among distress, social support, and natural killer (NK) cell activity in ovarian cancer patients in peripheral-blood mononuclear cells (PBMC), ascitic fluid, and tumor-infiltrating lymphocytes (TIL). PATIENTS AND METHODS Patients awaiting surgery for a pelvic mass suspected of being ovarian cancer completed psychological questionnaires and gave a presurgical sample of peripheral blood. Samples of tumor and ascites were taken during surgery, lymphocytes were then isolated, and NK cytotoxicity and percentage were determined. The final sample, which was confirmed by surgical diagnosis, included 42 patients with epithelial ovarian cancer and 23 patients with benign masses. RESULTS Peripheral NK cell activity was significantly lower among ovarian cancer patients than in patients with benign masses. Among ovarian cancer patients, NK cytotoxicity in TIL was significantly lower than in PBMC or ascitic fluid. Social support was related to higher NK cytotoxicity in PBMC and TIL, adjusting for stage. Distress was related to lower NK cytotoxicity in TIL. A multivariate model indicated independent associations of both distress and social support with NK cell activity in TIL. CONCLUSION Psychosocial factors, such as social support and distress, are associated with changes in the cellular immune response, not only in peripheral blood, but also at the tumor level. These relationships were more robust in TIL. These findings support the presence of stress influences in the tumor microenvironment.


Journal of Clinical Oncology | 2012

Lymphatic Mapping and Sentinel Lymph Node Biopsy in Women With Squamous Cell Carcinoma of the Vulva: A Gynecologic Oncology Group Study

Charles Levenback; Shamshad Ali; Robert L. Coleman; Michael A. Gold; Jeffrey M. Fowler; Patricia L. Judson; Maria C. Bell; Koen De Geest; Nick M. Spirtos; Ronald K. Potkul; Mario M. Leitao; Jamie N. Bakkum-Gamez; E.C. Rossi; Samuel S. Lentz; James J. Burke; Linda Van Le; Cornelia L. Trimble

PURPOSE To determine the safety of sentinel lymph node biopsy as a replacement for inguinal femoral lymphadenectomy in selected women with vulvar cancer. PATIENTS AND METHODS Eligible women had squamous cell carcinoma, at least 1-mm invasion, and tumor size ≥ 2 cm and ≤ 6 cm. The primary tumor was limited to the vulva, and there were no groin lymph nodes that were clinically suggestive of cancer. All women underwent intraoperative lymphatic mapping, sentinel lymph node biopsy, and inguinal femoral lymphadenectomy. Histologic ultra staging of the sentinel lymph node was prescribed. RESULTS In all, 452 women underwent the planned procedures, and 418 had at least one sentinel lymph node identified. There were 132 node-positive women, including 11 (8.3%) with false-negative nodes. Twenty-three percent of the true-positive patients were detected by immunohistochemical analysis of the sentinel lymph node. The sensitivity was 91.7% (90% lower confidence bound, 86.7%) and the false-negative predictive value (1-negative predictive value) was 3.7% (90% upper confidence bound, 6.1%). In women with tumor less than 4 cm, the false-negative predictive value was 2.0% (90% upper confidence bound, 4.5%). CONCLUSION Sentinel lymph node biopsy is a reasonable alternative to inguinal femoral lymphadenectomy in selected women with squamous cell carcinoma of the vulva.


Gynecologic Oncology | 2010

Serum biomarker panels for the discrimination of benign from malignant cases in patients with an adnexal mass

Brian M. Nolen; Liudmila Velikokhatnaya; Adele Marrangoni; Koen De Geest; Aleksey Lomakin; Robert C. Bast; Anna Lokshin

OBJECTIVES The diagnosis of an adnexal mass is a prevalent issue among women in the United States, although current methods of identifying those at high risk of malignancy remain insufficient. Ineffective triage of women with malignant masses is associated with delayed or inappropriate treatment and a negative effect on disease outcome. METHODS We performed an evaluation of 65 ovarian cancer-related biomarkers in the circulation of women diagnosed with an adnexal mass. Our subject group consisted of women diagnosed with benign masses and early- and late-stage ovarian cancer. RESULTS More than half of the biomarkers tested were found to differ significantly between benign and malignant cases. As individual markers, HE4 and CA-125 provided the greatest level of discrimination between benign and malignant cases, and the combination of these two biomarkers provided a higher level of discriminatory power than either marker considered alone. Multivariate statistical analysis identified several multimarker panels that could discriminate early-stage, late-stage, and combined ovarian cancers from benign cases with similar or slightly improved SN/SP levels to the CA-125/HE4 combination; however, these larger panels could not outperform the 2-biomarker panel in an independent validation set. We also identified a 3-biomarker panel with particular utility in premenopausal women. CONCLUSIONS Our findings serve to advance the development of blood-based screening methods for the discrimination of benign and malignant ovarian masses by confirming and expanding upon the superior utility of the CA-125/HE4 combination.


Clinical Cancer Research | 2008

HLA class I antigen processing machinery component expression and intratumoral T-cell infiltrate as independent prognostic markers in ovarian carcinoma

Liz Y. Han; Mavis S. Fletcher; Diana L. Urbauer; Peter R. Mueller; Charles N. Landen; Aparna A. Kamat; Yvonne G. Lin; William M. Merritt; Whitney A. Spannuth; Michael T. Deavers; Koen De Geest; David M. Gershenson; Susan K. Lutgendorf; Soldano Ferrone; Anil K. Sood

Purpose: Defects in the antigen processing machinery (APM) may provide tumor cells with a mechanism to escape immune recognition. The purpose of this study is to determine the clinical significance of APM component down-regulation and tumor-infiltrating T cells in ovarian carcinoma. Experimental Design: After institutional review board approval, tumor samples from 150 patients with invasive epithelial ovarian cancers were examined for TAP1, TAP2, tapasin, HLA class I heavy chain (HLA-HC), β2 microglobulin, and T-cell (CD3+ and CD8+) tumor infiltration using immunohistochemistry. Results: The majority of tumors had either heterogeneous or positive expression of TAP1, TAP2, HLA-HC, and β2 microglobulin (66.7%, 73.3%, 70.7%, and 63.3%, respectively), except tapasin for which 58% of the tumors lacked expression. Furthermore, 67% and 88% of the lesions possessed intratumoral and peritumoral CD3+ or CD8+ cells, respectively. The majority of APM component expression examined was significantly associated with both intratumoral and peritumoral T-cell infiltration (P < 0.05). The expression of APM components and the presence of intratumoral T-cell infiltrates were significantly associated with improved survival (all P ≤ 0.01); however, peritumoral T-cell infiltrates did not significantly affect survival (P = 0.33). APM component down-regulation (P < 0.001), lack of intratumoral T-cell infiltrates (P = 0.03), and suboptimal cytoreduction (P < 0.001) were independent prognostic markers for death from ovarian carcinoma. Conclusion: The negative effect of APM component down-regulation by itself and in combination with absent intratumoral T-cell infiltration on the survival of patients with ovarian carcinoma implies a role for immune escape in addition to immunosurveillance in the clinical course of disease.


Nature Communications | 2013

Src activation by adrenoreceptors is a key switch for tumour metastasis

Guillermo N. Armaiz-Pena; Julie K. Allen; Anthony Cruz; Rebecca L. Stone; Alpa M. Nick; Yvonne G. Lin; Liz Y. Han; Lingegowda S. Mangala; Gabriel J. Villares; Pablo Vivas-Mejia; Cristian Rodriguez-Aguayo; Archana S. Nagaraja; Kshipra M. Gharpure; Zheng Wu; Robert D. English; Kizhake V. Soman; Mian M.K. Shahzad; Maya Zigler; Michael T. Deavers; Alexander Zien; Theodoros Soldatos; David B. Jackson; John E. Wiktorowicz; Madeline Torres-Lugo; Tom Young; Koen De Geest; Gary E. Gallick; Menashe Bar-Eli; Gabriel Lopez-Berestein; Steve W. Cole

Norepinephrine (NE) can modulate multiple cellular functions important for cancer progression; however, how this single extracellular signal regulates such a broad array of cellular processes is unknown. Here, we identify Src as a key regulator of phosphoproteomic signaling networks activated in response to beta-adrenergic signaling in cancer cells. These results also identify a new mechanism of Src phosphorylation that mediates beta-adrenergic/PKA regulation of downstream networks, thereby enhancing tumor cell migration, invasion and growth. In human ovarian cancer samples, high tumoral NE levels were correlated with high pSrcY419 levels. Moreover, among cancer patients, the use of beta blockers was significantly associated with reduced cancer-related mortality. Collectively, these data provide a pivotal molecular target for disrupting neural signaling in the tumor microenvironment.


Journal of Clinical Oncology | 2012

Social Influences on Clinical Outcomes of Patients With Ovarian Cancer

Susan K. Lutgendorf; Koen De Geest; David Bender; Amina Ahmed; Michael J. Goodheart; Laila Dahmoush; M. Bridget Zimmerman; Frank J. Penedo; Joseph A. Lucci; Parvin Ganjei-Azar; Premal H. Thaker; Luis Mendez; David M. Lubaroff; George M. Slavich; Steven W. Cole; Anil K. Sood

PURPOSE Previous research has demonstrated relationships of social support with disease-related biomarkers in patients with ovarian cancer. However, the clinical relevance of these findings to patient outcomes has not been established. This prospective study examined how social support relates to long-term survival among consecutive patients with ovarian cancer. We focused on two types of social support: social attachment, a type of emotional social support reflecting connections with others, and instrumental social support reflecting the availability of tangible assistance. PATIENTS AND METHODS Patients were prospectively recruited during a presurgical clinic visit and completed surveys before surgery. One hundred sixty-eight patients with histologically confirmed epithelial ovarian cancer were observed from the date of surgery until death or December 2010. Clinical information was obtained from medical records. RESULTS In a Cox regression model, adjusting for disease stage, grade, histology, residual disease, and age, greater social attachment was associated with a lower likelihood of death (hazard ratio [HR], 0.87; 95% CI, 0.77 to 0.98; P = .018). The median survival time for patients with low social attachment categorized on a median split of 15 was 3.35 years (95% CI, 2.56 to 4.15 years). In contrast, by study completion, 59% of patients with high social attachment were still alive after 4.70 years. No significant association was found between instrumental social support and survival, even after adjustment for covariates. CONCLUSION Social attachment is associated with a survival advantage for patients with ovarian cancer. Clinical implications include the importance of screening for deficits in the social environment and consideration of support activities during adjuvant treatment.


Journal of Clinical Oncology | 2010

Phase II Clinical Trial of Ixabepilone in Patients With Recurrent or Persistent Platinum- and Taxane-Resistant Ovarian or Primary Peritoneal Cancer: A Gynecologic Oncology Group Study

Koen De Geest; Robert T. Morris; S. Diane Yamada; Bradley J. Monk; Susan Zweizig; Daniela Matei; Carolyn Y. Muller; William E. Richards

PURPOSE Ixabepilone (BMS-247550) is a microtubule-stabilizing epothilone B analog with activity in taxane-resistant metastatic breast cancer. The Gynecologic Oncology Group conducted a phase II evaluation of the efficacy and safety of ixabepilone in patients with recurrent or persistent platinum- and taxane-resistant primary ovarian or peritoneal carcinoma. PATIENTS AND METHODS Patients with measurable platinum- and taxane-resistant ovarian or peritoneal carcinoma, defined as progression during or within 6 months of one prior course of treatment with each agent, received intravenous ixabepilone 20 mg/m(2) administered over 1 hour on days 1, 8, and 15 of a 28-day cycle. Results Of 51 patients entered, 49 were eligible. The objective response rate was 14.3% (95% CI, 5.9% to 27.2%), with three complete and four partial responses. Twenty patients (40.8%) had stable disease, whereas sixteen (32.7%) had increasing disease. The median time to progression was 4.4 months (95% CI, 0.8 to 32.6+ months); median survival was 14.8 months (95% CI, 0.8 to 50.0) months. Patients received a median of two treatment cycles (range, 1 to 29 cycles), and 18.4% of patients received > or = six cycles. Adverse effects included peripheral grade 2 (28.5%) and grade 3 (6.1%) neuropathy, grades 3 to 4 neutropenia (20.4%), grade 3 fatigue (14.3%), grade 3 nausea/emesis (22%), grade 3 diarrhea (10%), and grade 3 mucositis (4%). CONCLUSION Ixabepilone 20 mg/m(2) over 1 hour on days 1, 8, and 15 of a 28-day cycle demonstrates antitumor activity and acceptable safety in patients with platinum- and taxane-resistant recurrent or persistent ovarian or primary peritoneal carcinoma.


Gynecologic Oncology | 2011

A Gynecologic Oncology Group phase II trial of the protein kinase C-beta inhibitor, enzastaurin and evaluation of markers with potential predictive and prognostic value in persistent or recurrent epithelial ovarian and primary peritoneal malignancies

Lydia Usha; Michael W. Sill; Kathleen M. Darcy; Doris M. Benbrook; Jean A. Hurteau; David P. Michelin; Robert S. Mannel; Parviz Hanjani; Koen De Geest; Andrew K. Godwin

OBJECTIVES Protein kinase C (PKC) activation contributes to proliferation and angiogenesis in epithelial ovarian or primary peritoneal carcinoma (EOC/PPC). A multi-institutional phase II trial was conducted to evaluate the efficacy and safety of PKCβ inhibitor enzastaurin in persistent or recurrent EOC/PPC and to explore potential prognostic and predictive biomarkers. METHODS Eligible women with measurable platinum-sensitive and resistant EOC/PPC were treated with continuous administration of oral enzastaurin until disease progression or unacceptable toxicity. A two-stage sequential design was used to evaluate progression-free survival (PFS) ≥6-months, tumor response, and toxicity. Translational studies included sequencing of the TP53, PTEN, PIK3CA and PKCβII genes for somatic mutations, quantitative PCR assays for AKT2 and PTEN copy number alterations, and measurement of circulating VEGF-A plasma levels. RESULTS Among 27 eligible and evaluable patients, 3 women with PFS≥6-months (11%) and 2 women with partial responses (7%) were observed. One of them achieved a durable response and remains on the study. No grade 4 adverse events were observed. Most common grade 3 adverse events were constitutional (4) and gastrointestinal (3). Mutations in the TP53 gene and abnormal copy number in the PTEN gene were common (56% and 48% of cases, respectively). CONCLUSIONS Enzastaurin was tolerable but had insufficient activity to proceed with the second stage of accrual. However, 1 patient has been progression-free for 44 months. No association between a biomarker and response to enzastaurin has been found. Exploratory analysis suggested an association between survival and PTEN copy number losses.

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Alpa M. Nick

University of Texas MD Anderson Cancer Center

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Amina Ahmed

University of Iowa Hospitals and Clinics

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Anil K. Sood

University of Texas MD Anderson Cancer Center

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Gabriel J. Villares

University of Texas MD Anderson Cancer Center

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Gabriel Lopez-Berestein

University of Texas MD Anderson Cancer Center

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Liz Y. Han

University of Texas MD Anderson Cancer Center

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Menashe Bar-Eli

University of Texas MD Anderson Cancer Center

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Michael T. Deavers

University of Texas MD Anderson Cancer Center

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