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Dive into the research topics where Kent A. Griffith is active.

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Featured researches published by Kent A. Griffith.


Cancer Research | 2011

Aldehyde Dehydrogenase in Combination with CD133 Defines Angiogenic Ovarian Cancer Stem Cells That Portend Poor Patient Survival

Ines Silva; Shoumei Bai; Karen McLean; Kun Yang; Kent A. Griffith; Dafydd G. Thomas; Christophe Ginestier; Carolyn Johnston; Angela Kueck; R. Kevin Reynolds; Max S. Wicha; Ronald J. Buckanovich

Markers that reliably identify cancer stem cells (CSC) in ovarian cancer could assist prognosis and improve strategies for therapy. CD133 is a reported marker of ovarian CSC. Aldehyde dehydrogenase (ALDH) activity is a reported CSC marker in several solid tumors, but it has not been studied in ovarian CSC. Here we report that dual positivity of CD133 and ALDH defines a compelling marker set in ovarian CSC. All human ovarian tumors and cell lines displayed ALDH activity. ALDH(+) cells isolated from ovarian cancer cell lines were chemoresistant and preferentially grew tumors, compared with ALDH(-) cells, validating ALDH as a marker of ovarian CSC in cell lines. Notably, as few as 1,000 ALDH(+) cells isolated directly from CD133(-) human ovarian tumors were sufficient to generate tumors in immunocompromised mice, whereas 50,000 ALDH(-) cells were unable to initiate tumors. Using ALDH in combination with CD133 to analyze ovarian cancer cell lines, we observed even greater growth in the ALDH(+)CD133(+) cells compared with ALDH(+)CD133(-) cells, suggesting a further enrichment of ovarian CSC in ALDH(+)CD133(+) cells. Strikingly, as few as 11 ALDH(+)CD133(+) cells isolated directly from human tumors were sufficient to initiate tumors in mice. Like other CSC, ovarian CSC exhibited increased angiogenic capacity compared with bulk tumor cells. Finally, the presence of ALDH(+)CD133(+) cells in debulked primary tumor specimens correlated with reduced disease-free and overall survival in ovarian cancer patients. Taken together, our findings define ALDH and CD133 as a functionally significant set of markers to identify ovarian CSCs.


Blood | 2012

A phase 1/2 study of carfilzomib in combination with lenalidomide and low-dose dexamethasone as a frontline treatment for multiple myeloma.

Andrzej J. Jakubowiak; Dominik Dytfeld; Kent A. Griffith; Daniel Lebovic; David H. Vesole; Sundar Jagannath; Ammar Al-Zoubi; Tara Anderson; Brian K. Nordgren; Kristen Detweiler-Short; Keith Stockerl-Goldstein; Asra Ahmed; Terri L. Jobkar; Diane E. Durecki; Kathryn McDonnell; Melissa Mietzel; Daniel R. Couriel; Mark S. Kaminski; Ravi Vij

This phase 1/2 study in patients with newly diagnosed multiple myeloma (N = 53) assessed CRd--carfilzomib (20, 27, or 36 mg/m2, days 1, 2, 8, 9, 15, 16 and 1, 2, 15, 16 after cycle 8), lenalidomide (25 mg/d, days 1-21), and weekly dexamethasone (40/20 mg cycles 1-4/5+)--in 28-day cycles. After cycle 4, transplantation-eligible candidates underwent stem cell collection (SCC) then continued CRd with the option of transplantation. The maximum planned dose level (carfilzomib 36 mg/m2) was expanded in phase 2 (n = 36). Thirty-five patients underwent SCC, 7 proceeded to transplantation, and the remainder resumed CRd. Grade 3/4 toxicities included hypophosphatemia (25%), hyperglycemia (23%), anemia (21%), thrombocytopenia (17%), and neutropenia (17%); peripheral neuropathy was limited to grade 1/2 (23%). Most patients did not require dose modifications. After a median of 12 cycles (range, 1-25), 62% (N = 53) achieved at least near-complete response (CR) and 42% stringent CR. Responses were rapid and improved during treatment. In 36 patients completing 8 or more cycles, 78% reached at least near CR and 61% stringent CR. With median follow-up of 13 months (range, 4-25 months), 24-month progression-free survival estimate was 92%. CRd was well tolerated with exceptional response rates. This study is registered at http://www.clinicaltrials.gov as NCT01029054.


Journal of Clinical Oncology | 2006

Meta-Analysis of Survival in African American and White American Patients With Breast Cancer: Ethnicity Compared With Socioeconomic Status

Lisa A. Newman; Kent A. Griffith; Ismail Jatoi; Michael S. Simon; Joseph P. Crowe; Graham A. Colditz

PURPOSE The extent to which socioeconomic disadvantages and inadequate health care access account for the disproportionately elevated mortality hazard observed in African American compared with white American patients with breast cancer is poorly defined. METHODS We identified 20 studies reported between January 1980 and June 2005 that provided survival analyses in patients with breast cancer after adjusting for ethnicity and some measurement of socioeconomic status. These studies also adjusted for age and stage of disease at time of diagnosis. RESULTS The pooled outcome data yielded estimates for the mortality hazard in 14,013 African American and 76,111 white American patients with breast cancer. Studies varied in their methods for assigning socioeconomic status, with most relying on area-wide measures such as census tract and census block data. The combined analysis (adjusted for age, stage, and socioeconomic status) revealed that African American ethnicity was associated with a statistically significant excess mortality risk in overall survival (mortality hazard, 1.27; 95% CI, 1.18 to 1.38) and in breast cancer-specific survival (mortality hazard, 1.19; 95% CI, 1.10 to 1.29). CONCLUSION Our pooled analysis demonstrated that African American ethnicity is a significant and independent predictor of poor outcome from breast cancer, even after accounting for socioeconomic status by conventional measures. These findings support the need for further investigation of the biologic, genetic, and sociocultural factors that may influence survival in African American patients with breast cancer.


International Journal of Radiation Oncology Biology Physics | 2010

Unacceptable Cosmesis in a Protocol Investigating Intensity-Modulated Radiotherapy With Active Breathing Control for Accelerated Partial-Breast Irradiation

Reshma Jagsi; Merav Ben-David; Jean M. Moran; Robin Marsh; Kent A. Griffith; James A. Hayman; Lori J. Pierce

PURPOSE To report interim cosmetic results and toxicity from a prospective study evaluating accelerated partial-breast irradiation (APBI) administered using a highly conformal external beam approach. METHODS AND MATERIALS We enrolled breast cancer patients in an institutional review board-approved prospective study of APBI using beamlet intensity-modulated radiotherapy (IMRT) at deep-inspiration breath-hold. Patients received 38.5 Gy in 3.85 Gy fractions twice daily. Dosimetric parameters in patients who maintained acceptable cosmesis were compared with those in patients developing unacceptable cosmesis in follow-up, using t-tests. RESULTS Thirty-four patients were enrolled; 2 were excluded from analysis because of fair baseline cosmesis. With a median follow-up of 2.5 years, new unacceptable cosmesis developed in 7 patients, leading to early study closure. We compared patients with new unacceptable cosmesis with those with consistently acceptable cosmesis. Retrospective analysis demonstrated that all but one plan adhered to the dosimetric requirements of the national APBI trial. The mean proportion of a whole-breast reference volume receiving 19.25 Gy (V50) was lower in patients with acceptable cosmesis than in those with unacceptable cosmesis (34.6% vs. 46.1%; p = 0.02). The mean percentage of this reference volume receiving 38.5 Gy (V100) was also lower in patients with acceptable cosmesis (15.5% vs. 23.0%; p = 0.02). CONCLUSIONS The hypofractionated schedule and parameters commonly used for external beam APBI and prescribed by the ongoing national trial may be suboptimal, at least when highly conformal techniques such as IMRT with management of breathing motion are used. The V50 and V100 of the breast reference volume seem correlated with cosmetic outcome, and stricter limits may be appropriate in this setting.


Cancer | 2003

Clinicopathologic features of metastasis in nonsentinel lymph nodes of breast carcinoma patients: A metaanalysis

Amy C. Degnim; Kent A. Griffith; Michael S. Sabel; Daniel F. Hayes; Vincent M. Cimmino; Kathleen M. Diehl; Peter C. Lucas; Matthew Snyder; Alfred E. Chang; Lisa A. Newman

In breast carcinoma patients with a positive sentinel lymph node (SN), the value of complete axillary lymph node dissection has been questioned. Multiple published reports have attempted to identify clinicopathologic characteristics of the primary tumor and SN that are associated with an increased likelihood of positive nonsentinel lymph nodes (NSN). Because of differences in lymph node evaluation techniques and limited patient numbers in each study, the authors performed a meta‐analysis to assess the regularity and relative strength of association between various characteristics and the risk of NSN metastasis.


Cancer | 2007

The impact of factors beyond breslow depth on predicting sentinel lymph node positivity in melanoma

Sandra C. Paek; Kent A. Griffith; Timothy M. Johnson; Vernon K. Sondak; Sandra L. Wong; Alfred E. Chang; Vincent M. Cimmino; Lori Lowe; Carol R. Bradford; Riley S. Rees; Michael S. Sabel

In addition to Breslow depth, the authors previously described how increasing mitotic rate and decreasing age predicted sentinel lymph node (SLN) metastases in patients with melanoma. The objectives of the current study were to verify those previous results and to create a prediction model for the better selection of which patients with melanoma should undergo SLN biopsy.


Neurosurgery | 2004

The role of radiation therapy after surgical resection of nonfunctional pituitary macroadenomas.

Paul Park; William F. Chandler; Ariel L. Barkan; John J. Orrego; John A. Cowan; Kent A. Griffith; Christina Tsien

OBJECTIVE:Radiotherapy after aggressive surgical resection of nonfunctional macroadenoma (NFA) of the pituitary remains controversial. Historically, immediate postoperative radiotherapy has been recommended to decrease risk of recurrence. With the availability of high-resolution imaging, most neurosurgeons now withhold radiation until recurrence. There is relatively little evidence to support this practice, however. This study reviews postoperative results in a large number of patients with NFA, the majority of whom did not undergo prophylactic radiation. METHODS:Of the 258 patients who underwent surgery from 1979 to 1999 for NFA, medical records were available for 176. Forty-four patients were treated with immediate postoperative radiotherapy after tumor resection, and the remaining 132 patients were followed up with serial imaging studies and treated with radiotherapy only when a recurrence was documented by follow-up imaging. RESULTS:Patients in the group that received immediate postoperative radiotherapy at time of initial diagnosis and surgery did not differ significantly with respect to age or sex from those in the group that was observed. Five- and 10-year recurrence rates were 2.3 and 2.3%, respectively, for patients who received immediate postoperative radiotherapy, as compared with 15.2 and 50.5%, respectively, for patients who were followed up and did not receive radiotherapy unless there was evidence of recurrence or progression. No patient had symptomatic recurrence in the group that was observed if consistent follow-up was performed. Of the 26 patients who received radiotherapy at time of tumor recurrence or progression, 18 had adequate follow-up, and in all cases, the tumors either remained stable or regressed. CONCLUSION:Withholding radiotherapy after a high-percentage resection of NFA leads to a higher recurrence rate, but it avoids exposing all patients to the risks of radiation. Deferring radiotherapy for patients with complete or near-complete resection seems to be a safe and prudent approach, as our data suggest that recurrences may be detected early with high-resolution imaging and treated effectively with radiation at time of recurrence. Therefore, immediate postoperative radiotherapy may be eliminated for patients with complete or near complete resection of NFA and who agree to undergo close follow-up for a long period.


BMC Complementary and Alternative Medicine | 2007

Ginger inhibits cell growth and modulates angiogenic factors in ovarian cancer cells

Jennifer M. Rhode; Sarah Fogoros; Suzanna M. Zick; Heather Wahl; Kent A. Griffith; Jennifer Huang; J. Rebecca Liu

BackgroundGinger (Zingiber officinale Rosc) is a natural dietary component with antioxidant and anticarcinogenic properties. The ginger component [6]-gingerol has been shown to exert anti-inflammatory effects through mediation of NF-κB. NF-κB can be constitutively activated in epithelial ovarian cancer cells and may contribute towards increased transcription and translation of angiogenic factors. In the present study, we investigated the effect of ginger on tumor cell growth and modulation of angiogenic factors in ovarian cancer cells in vitro.MethodsThe effect of ginger and the major ginger components on cell growth was determined in a panel of epithelial ovarian cancer cell lines. Activation of NF-κB and and production of VEGF and IL-8 was determined in the presence or absence of ginger.ResultsGinger treatment of cultured ovarian cancer cells induced profound growth inhibition in all cell lines tested. We found that in vitro, 6-shogaol is the most active of the individual ginger components tested. Ginger treatment resulted in inhibition of NF-kB activation as well as diminished secretion of VEGF and IL-8.ConclusionGinger inhibits growth and modulates secretion of angiogenic factors in ovarian cancer cells. The use of dietary agents such as ginger may have potential in the treatment and prevention of ovarian cancer.


Cancer Research | 2005

Protein Kinase Cε Is a Predictive Biomarker of Aggressive Breast Cancer and a Validated Target for RNA Interference Anticancer Therapy

Quintin Pan; Li Wei Bao; Celina G. Kleer; Michael S. Sabel; Kent A. Griffith; Theodoros N. Teknos; Sofia D. Merajver

Tumor metastasis is the major cause of morbidity and mortality in patients with breast cancer. It is critical to identify metastasis enabling genes and understand how they are responsible for inducing specific aspects of the metastatic phenotype to allow for improved clinical detection and management. Protein kinase C epsilon (PKC epsilon), a member of a family of serine/threonine protein kinases, is a transforming oncogene that has been reported to be involved in cell invasion and motility. In this study, we investigated the role of PKC epsilon in breast cancer development and progression. High-density tissue microarray analysis showed that PKC epsilon protein was detected in 73.6% (106 of 144) of primary tumors from invasive ductal breast cancer patients. Increasing PKC epsilon staining intensity was associated with high histologic grade (P = 0.0206), positive Her2/neu receptor status (P = 0.0419), and negative estrogen (P = 0.0026) and progesterone receptor status (P = 0.0008). Kaplan-Meier analyses showed that PKC epsilon was significantly associated with poorer disease-free and overall survival (log-rank, P = 0.0478 and P = 0.0414, respectively). RNA interference of PKC epsilon in MDA-MB231 cells, an aggressive breast cancer cell line with elevated PKC epsilon levels, resulted in a cell phenotype that was significantly less proliferative, invasive, and motile than the parental or the control RNA interference transfectants. Moreover, in vivo tumor growth of small interfering RNA-PKC epsilon MDA-MB231 clones was retarded by a striking 87% (P < 0.05) and incidence of lung metastases was inhibited by 83% (P < 0.02). PKC epsilon-deficient clones were found to have lower RhoC GTPase protein levels and activation. Taken together, these results revealed that PKC epsilon plays a critical and causative role in promoting an aggressive metastatic breast cancer phenotype and as a target for anticancer therapy.


Journal of Clinical Oncology | 2011

Features Predicting Sentinel Lymph Node Positivity in Merkel Cell Carcinoma

Jennifer L. Schwartz; Kent A. Griffith; Lori Lowe; Sandra L. Wong; Scott A. McLean; Douglas R. Fullen; Christopher D. Lao; James A. Hayman; Carol R. Bradford; Riley S. Rees; Timothy M. Johnson; Christopher K. Bichakjian

PURPOSE Merkel cell carcinoma (MCC) is a relatively rare, potentially aggressive cutaneous malignancy. We examined the clinical and histologic features of primary MCC that may correlate with the probability of a positive sentinel lymph node (SLN). METHODS Ninety-five patients with MCC who underwent SLN biopsy at the University of Michigan were identified. SLN biopsy was performed on 97 primary tumors, and an SLN was identified in 93 instances. These were reviewed for clinical and histologic features and associated SLN positivity. Univariate associations between these characteristics and a positive SLN were tested for by using either the χ(2) or the Fishers exact test. A backward elimination algorithm was used to help create a best multiple variable model to explain a positive SLN. RESULTS SLN positivity was significantly associated with the clinical size of the lesion, greatest horizontal histologic dimension, tumor thickness, mitotic rate, and histologic growth pattern. Two competing multivariate models were generated to predict a positive SLN. The histologic growth pattern was present in both models and combined with either tumor thickness or mitotic rate. CONCLUSION Increasing clinical size, increasing tumor thickness, increasing mitotic rate, and infiltrative tumor growth pattern were significantly associated with a greater likelihood of a positive SLN. By using the growth pattern and tumor thickness model, no subgroup of patients was predicted to have a lower than 15% to 20% likelihood of a positive SLN. This suggests that all patients presenting with MCC without clinical evidence of regional lymph node disease should be considered for SLN biopsy.

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Robin Marsh

University of Michigan

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