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Dive into the research topics where Theodoros N. Teknos is active.

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Featured researches published by Theodoros N. Teknos.


Journal of Clinical Oncology | 2008

EGFR, p16, HPV Titer, Bcl-xL and p53, Sex, and Smoking As Indicators of Response to Therapy and Survival in Oropharyngeal Cancer

Bhavna Kumar; Kitrina G. Cordell; Julia S. Lee; Francis P. Worden; Mark E. Prince; Huong H. Tran; Gregory T. Wolf; Susan G. Urba; Douglas B. Chepeha; Theodoros N. Teknos; Avraham Eisbruch; Christina Tsien; Jeremy M. G. Taylor; Nisha J. D'Silva; Kun Yang; David M. Kurnit; Joshua A. Bauer; Carol R. Bradford; Thomas E. Carey

PURPOSE To prospectively identify markers of response to therapy and outcome in an organ-sparing trial for advanced oropharyngeal cancer. PATIENTS AND METHODS Pretreatment biopsies were examined for expression of epidermal growth factor receptor (EGFR), p16, Bcl-xL, and p53 as well as for p53 mutation. These markers were assessed for association with high-risk human papillomavirus (HPV), response to therapy, and survival. Patient variables included smoking history, sex, age, primary site, tumor stage, and nodal status. RESULTS EGFR expression was inversely associated with response to induction chemotherapy (IC) (P = .01), chemotherapy/radiotherapy (CRT; P = .055), overall survival (OS; P = .001), and disease-specific survival (DSS; P = .002) and was directly associated with current smoking (P = .04), female sex (P = .053), and lower HPV titer (P = .03). HPV titer was significantly associated with p16 expression (P < .0001); p16 was significantly associated with response to IC (P = .008), CRT (P = .009), OS (P = .001), and DSS (P = .003). As combined markers, lower HPV titer and high EGFR expression were associated with worse OS (rho(EGFR) = 0.008; rho(HPV) = 0.03) and DSS (rho(EGFR) = 0.01; rho(HPV) = 0.016). In 36 of 42 biopsies, p53 was wild-type, and only one HPV-positive tumor had mutant p53. The combination of low p53 and high Bcl-xL expression was associated with poor OS (P = .005) and DSS (P = .002). CONCLUSION Low EGFR and high p16 (or higher HPV titer) expression are markers of good response to organ-sparing therapy and outcome, whereas high EGFR expression, combined low p53/high Bcl-xL expression, female sex, and smoking are associated with a poor outcome. Smoking cessation and strategies to target EGFR and Bcl-xL are important adjuncts to the treatment of oropharyngeal cancer.


Journal of Clinical Oncology | 2008

Chemoselection As a Strategy for Organ Preservation in Advanced Oropharynx Cancer: Response and Survival Positively Associated With HPV16 Copy Number

Francis P. Worden; Bhavna Kumar; Julia S. Lee; Gregory T. Wolf; Kitrina G. Cordell; Jeremy M. G. Taylor; Susan G. Urba; Avraham Eisbruch; Theodoros N. Teknos; Douglas B. Chepeha; Mark E. Prince; Christina Tsien; Nisha J. D'Silva; Kun Yang; David M. Kurnit; Heidi L. Mason; Tamara H. Miller; Nancy E. Wallace; Carol R. Bradford; Thomas E. Carey

PURPOSE To test induction chemotherapy (IC) followed by concurrent chemoradiotherapy (CRT) or surgery/radiotherapy (RT) for advanced oropharyngeal cancer and to assess the effect of human papilloma virus (HPV) on response and outcome. PATIENTS AND METHODS Sixty-six patients (51 male; 15 female) with stage III to IV squamous cell carcinoma of the oropharynx (SCCOP) were treated with one cycle of cisplatin (100 mg/m(2)) or carboplatin (AUC 6) and with fluorouracil (1,000 mg/m(2)/d for 5 days) to select candidates for CRT. Those achieving a greater than 50% response at the primary tumor received CRT (70 Gy; 35 fractions with concurrent cisplatin 100 mg/m(2) or carboplatin (AUC 6) every 21 days for three cycles). Adjuvant paclitaxel was given to patients who were complete histologic responders. Patients with a response of 50% or less underwent definitive surgery and postoperative radiation. Pretreatment biopsies from 42 patients were tested for high-risk HPV. RESULTS Fifty-four of 66 patients (81%) had a greater than 50% response after IC. Of these, 53 (98%) received CRT, and 49 (92%) obtained complete histologic response with a 73.4% (47 of 64) rate of organ preservation. The 4-year overall survival (OS) was 70.4%, and the disease-specific survival (DSS) was 75.8% (median follow-up, 64.1 months). HPV16, found in 27 of 42 (64.3%) biopsies, was associated with younger age (median, 55 v 63 years; P = .016), sex (22 of 30 males [73.3%] and five of 12 females [41.7%]; P = .08), and nonsmoking status (P = .037). HPV titer was significantly associated with IC response (P = .001), CRT response (P = .005), OS (P = .007), and DSS (P = .008). CONCLUSION Although the numbers in this study are small, IC followed by CRT is an effective treatment for SCCOP, especially in patients with HPV-positive tumors; however, for patients who do not respond to treatment, alternative treatments must be developed.


Molecular Cancer Research | 2011

IL-6 Promotes Head and Neck Tumor Metastasis by Inducing Epithelial–Mesenchymal Transition via the JAK-STAT3-SNAIL Signaling Pathway

Arti Yadav; Bhavna Kumar; Jharna Datta; Theodoros N. Teknos; Pawan Kumar

Epithelial–mesenchymal transition (EMT) is a key process in tumor metastatic cascade that is characterized by the loss of cell–cell junctions and cell polarity, resulting in the acquisition of migratory and invasive properties. However, the precise molecular events that initiate this complex EMT process in head and neck cancers are poorly understood. Increasing evidence suggests that tumor microenvironment plays an important role in promoting EMT in tumor cells. We have previously shown that head and neck tumors exhibit significantly higher Bcl-2 expression in tumor-associated endothelial cells and overexpression of Bcl-2 alone in tumor-associated endothelial cells was sufficient to enhance tumor metastasis of oral squamous cell carcinoma in a severe combined immunodeficient (SCID) mouse model. In this study, we show that endothelial cells expressing Bcl-2 (EC-Bcl-2), when cocultured with head and neck tumor cells (CAL27), significantly enhance EMT-related changes in tumor cells predominantly by the secretion of IL-6. Treatment with recombinant IL-6 or stable IL-6 overexpression in CAL27 cells or immortalized oral epithelial cells (IOE) significantly induced the expression of mesenchymal marker, vimentin, while repressing E-cadherin expression via the JAK/STAT3/Snail signaling pathway. These EMT-related changes were further associated with enhanced tumor and IOE cell scattering and motility. STAT3 knockdown significantly reversed IL-6–mediated tumor and IOE cell motility by inhibiting FAK activation. Furthermore, tumor cells overexpressing IL-6 showed marked increase in lymph node and lung metastasis in a SCID mouse xenograft model. Taken together, these results show a novel function for IL-6 in mediating EMT in head and neck tumor cells and increasing their metastatic potential. Mol Cancer Res; 9(12); 1658–67. ©2011 AACR.


Clinical Cancer Research | 2010

Tobacco Use in Human Papillomavirus–Positive Advanced Oropharynx Cancer Patients Related to Increased Risk of Distant Metastases and Tumor Recurrence

Jessica H. Maxwell; Bhavna Kumar; Felix Y. Feng; Francis P. Worden; Julia S. Lee; Avraham Eisbruch; Gregory T. Wolf; Mark E. Prince; Jeffrey S. Moyer; Theodoros N. Teknos; Douglas B. Chepeha; Jonathan B. McHugh; Susan G. Urba; Jay Stoerker; Heather M. Walline; David M. Kurnit; Kitrina G. Cordell; Samantha J. Davis; Preston D. Ward; Carol R. Bradford; Thomas E. Carey

Purpose: The goal of this study was to examine the effect of tobacco use on disease recurrence (local/regional recurrence, distant metastasis, or second primary) among patients with human papillomavirus (HPV)–positive squamous cell carcinoma of the oropharynx (SCCOP) following a complete response to chemoradiation therapy. Experimental Design: Between 1999 and 2007, 124 patients with advanced SCCOP (86% with stage IV) and adequate tumor tissue for HPV analysis who were enrolled in one of two consecutive University of Michigan treatment protocols were prospectively included in this study. Patients were categorized as never-, former, or current tobacco users. The primary end points were risk of disease recurrence and time to recurrence; secondary end points were disease-specific survival and overall survival. Results: One hundred and two patients (82.3%) had HPV-positive tumors. Over two thirds (68%) of patients with HPV-positive tumors were tobacco users. Among HPV-positive patients, current tobacco users were at significantly higher risk of disease recurrence than never-tobacco users (hazard ratio, 5.2; confidence interval, 1.1-24.4; P = 0.038). Thirty-five percent of HPV-positive ever tobacco users recurred compared with only 6% of HPV-positive never users and 50% of HPV-negative patients. All HPV-negative patients were tobacco users and had significantly shorter times to recurrence (P = 0.002), and had reduced disease-specific survival (P = 0.004) and overall survival (P < 0.001) compared with HPV-positive patients. Compared with HPV-positive never-tobacco users, those with a tobacco history showed a trend for reduced disease-specific survival (P = 0.064) but not overall survival (P = 0.221). Conclusions: Current tobacco users with advanced, HPV-positive SCCOP are at higher risk of disease recurrence compared with never-tobacco users. Clin Cancer Res; 16(4); 1226–35


Cancer | 2008

Interleukin‐6 predicts recurrence and survival among head and neck cancer patients

Sonia A. Duffy; Jeremy M. G. Taylor; Jeffrey E. Terrell; Mozaffarul Islam; Yun Li; Karen E. Fowler; Gregory T. Wolf; Theodoros N. Teknos

Increased pretreatment serum interleukin (IL)‐6 levels among patients with head and neck squamous cell carcinoma (HNSCC) have been shown to correlate with poor prognosis, but sample sizes in prior studies have been small and thus unable to control for other known prognostic variables.


Journal of Clinical Oncology | 2006

Single-Cycle Induction Chemotherapy Selects Patients With Advanced Laryngeal Cancer for Combined Chemoradiation: A New Treatment Paradigm

Susan G. Urba; Gregory T. Wolf; Avraham Eisbruch; Francis P. Worden; Julia Lee; Carol R. Bradford; Theodoros N. Teknos; Douglas B. Chepeha; Mark E. Prince; Norman D. Hogikyan; Jeremy M. G. Taylor

PURPOSE Primary chemoradiotherapy in patients with advanced laryngeal cancer can achieve high rates of organ preservation without sacrificing survival compared with radiation alone or conventional laryngectomy. Appropriate selection of patients for organ preservation approaches could enhance overall treatment outcome and quality of life. We conducted a phase II organ preservation trial for patients with stage III and IV larynx cancer to determine whether late salvage surgery rates could be decreased and survival improved by selecting patients for organ preservation based on response to a single cycle of induction chemotherapy. PATIENTS AND METHODS The chemotherapy was cisplatin 100 mg/m2 on day 1 and fluorouracil 1,000 mg/m(2)/d for 5 days. Patients who achieved less than 50% response had immediate laryngectomy. Patients who achieved more than 50% response went on to concurrent chemoradiotherapy. Histologic complete responders after chemoradiotherapy received two more cycles of chemotherapy. Patients with residual disease after chemoradiotherapy had planned salvage surgery. RESULTS Of 97 eligible patients, 73 (75%) achieved more than 50% response and received chemoradiotherapy. A total of 29 patients (30%) had salvage surgery; 19 patients (20%) had early salvage surgery after the single cycle of induction chemotherapy, three patients (3%) had late salvage surgery after chemoradiotherapy, six patients (6%) eventually had salvage surgery for recurrence, and one patient had laryngectomy for chondroradionecrosis. The median follow-up time was 41.9 months. The overall survival rate at 3 years is 85%. The cause-specific survival rate was 87%. Larynx preservation was achieved in 69 patients (70%). CONCLUSION These results confirm excellent larynx preservation and improved overall survival rates compared with historical results.


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.


Laryngoscope | 2002

Paranasal sinus malignancies: An 18-year single institution experience

Larry L. Myers; Brian Nussenbaum; Carol R. Bradford; Theodoros N. Teknos; Ramon M. Esclamado; Gregory T. Wolf

Objectives To characterize a single institution experience with management of paranasal sinus malignancies during an 18‐year time period, report long‐term survival rates, and identify prognostic factors.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2002

Functional assessment using Constant's Shoulder Scale after modified radical and selective neck dissection.

Douglas B. Chepeha; Rodney J. Taylor; Judith C. Chepeha; Theodoros N. Teknos; Carol R. Bradford; Pramod K. Sharma; Jeffrey E. Terrell; Gregory T. Wolf

Constants Shoulder Scale is a validated and widely applied instrument for assessment of shoulder function. We used this instrument to assess which treatment and demographic variables contribute to shoulder dysfunction after neck dissection in head and neck cancer patients.


Archives of Otolaryngology-head & Neck Surgery | 2013

Transoral robotic surgery for oropharyngeal cancer: long-term quality of life and functional outcomes.

Peter T. Dziegielewski; Theodoros N. Teknos; Kasim Durmus; Matthew Old; Amit Agrawal; Kiran Kakarala; Anna M. Marcinow; Enver Ozer

IMPORTANCE Because treatment for oropharyngeal squamous cell carcinoma (OPSCC), especially in patients of older age, is associated with decreased patient quality of life (QOL) after surgery, demonstration of a less QOL-impairing treatment technique would improve patient satisfaction substantially. OBJECTIVE To determine swallowing, speech, and QOL outcomes following transoral robotic surgery (TORS) for OPSCC. DESIGN, PARTICIPANTS, AND SETTING This prospective cohort study of 81 patients with previously untreated OPSCC was conducted at a tertiary care academic comprehensive cancer center. INTERVENTIONS Primary surgical resection via TORS and neck dissection as indicated. MAIN OUTCOMES AND MEASURES Patients were asked to complete the Head and Neck Cancer Inventory (HNCI) preoperatively and at 3 weeks as well as 3, 6, and 12 months postoperatively. Swallowing ability was assessed by independence from a gastrostomy tube (G-tube). Clinicopathologic and follow-up data were also collected. RESULTS Mean follow-up time was 22.7 months. The HNCI response rates at 3 weeks and 3, 6, and 12 months were 79%, 60%, 63%, and 67% respectively. There were overall declines in speech, eating, aesthetic, social, and overall QOL domains in the early postoperative periods. However, at 1 year post TORS, scores for aesthetic, social, and overall QOL remained high. Radiation therapy was negatively correlated with multiple QOL domains (P < .05 for all comparisons), while age older than 55 years correlated with lower speech and aesthetic scores (P < .05 for both). Human papillomavirus status did not correlate with any QOL domain. G-tube rates at 6 and 12 months were 24% and 9%, respectively. Greater extent of TORS (>1 oropharyngeal site resected) and age older than 55 years predicted the need for a G-tube at any point after TORS (P < .05 for both). CONCLUSIONS AND RELEVANCE Patients with OPSCC treated with TORS maintain a high QOL at 1 year after surgery. Adjuvant treatment and older age tend to decrease QOL. Patients meeting these criteria should be counseled appropriately.

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Enver Ozer

The Ohio State University Wexner Medical Center

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Pawan Kumar

University of Michigan

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Quintin Pan

The Ohio State University Wexner Medical Center

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