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1.
Oncologist ; 23(7): 782-790, 2018 07.
Article in English | MEDLINE | ID: mdl-29572245

ABSTRACT

PURPOSE: This study evaluated the maximum tolerated dose or recommended phase II dose (RPTD) and safety and tolerability of the ganitumab and everolimus doublet regimen followed by the ganitumab, everolimus, and panitumumab triplet regimen. MATERIALS AND METHODS: This was a standard 3 + 3 dose escalation trial. Doublet therapy consisted of ganitumab at 12 mg/kg every 2 weeks; doses of everolimus were adjusted according to dose-limiting toxicities (DLTs). Panitumumab at 4.8 mg/kg every 2 weeks was added to the RPTD of ganitumab and everolimus. DLTs were assessed in cycle 1; toxicity evaluation was closely monitored throughout treatment. Treatment continued until disease progression or undesirable toxicity. Pretreatment and on-treatment skin biopsies were collected to assess insulin-like growth factor 1 receptor and mammalian target of rapamycin (mTOR) target modulation. RESULTS: Forty-three subjects were enrolled. In the doublet regimen, two DLTs were observed in cohort 1, no DLTs in cohort -1, and one in cohort -1B. The triplet combination was discontinued because of unacceptable toxicity. Common adverse events were thrombocytopenia/neutropenia, skin rash, mucositis, fatigue, and hyperglycemia. In the doublet regimen, two patients with refractory non-small cell lung cancer (NSCLC) achieved prolonged complete responses ranging from 18 to >60 months; one treatment-naïve patient with chondrosarcoma achieved prolonged stable disease >24 months. In dermal granulation tissue, the insulin-like growth factor receptor and mTOR pathways were potently and specifically inhibited by ganitumab and everolimus, respectively. CONCLUSION: The triplet regimen of ganitumab, everolimus, and panitumumab was associated with unacceptable toxicity. However, the doublet of ganitumab at 12 mg/kg every 2 weeks and everolimus five times weekly had an acceptable safety profile and demonstrated notable clinical activity in patients with refractory NSCLC and sarcoma. IMPLICATIONS FOR PRACTICE: This trial evaluated the maximum tolerated dose or recommended phase II dose and safety and tolerability of the ganitumab and everolimus doublet regimen followed by the ganitumab, everolimus, and panitumumab triplet regimen. Although the triplet regimen of ganitumab, everolimus, and panitumumab was associated with unacceptable toxicity, the doublet of ganitumab at 12 mg/kg every 2 weeks and everolimus at five times weekly had an acceptable safety profile and demonstrated notable clinical activity in patients with refractory non-small cell lung cancer and sarcoma.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Neoplasms/drug therapy , Adult , Aged , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal, Humanized , Biomarkers, Tumor/metabolism , Dose-Response Relationship, Drug , Everolimus/administration & dosage , Female , Humans , Male , Middle Aged , Neoplasms/genetics , Neoplasms/metabolism , Neoplasms/pathology , Panitumumab/administration & dosage , Receptor, IGF Type 1 , Receptors, Somatomedin/immunology
2.
Support Care Cancer ; 23(5): 1311-9, 2015 May.
Article in English | MEDLINE | ID: mdl-25341548

ABSTRACT

PURPOSE: Palmar-plantar erythrodysesthesia (PPE) is a common chemotherapy and anti-VEGF multi-kinase inhibitor class-related toxicity that often results in debilitating skin changes and often limits the use of active anti-cancer regimens. Mechanistic and anecdotal clinical evidence suggested that topical application of sildenafil cream may help reduce the severity of PPE. Therefore, we conducted a randomized, double-blind, placebo-controlled pilot study to evaluate the feasibility, safety and efficacy of topical sildenafil cream for the treatment of PPE. METHODS: Eligible subjects were required to have grade 1-3 PPE associated with either capecitabine or sunitinib. Subjects were randomized to receive 1 % topical sildenafil cream to the left extremities or right extremities and placebo cream on the opposite extremity. Two times per day, 0.5 mL of cream was applied to each affected hand/foot. The primary endpoint was improvement in PPE grading at any point on study. Clinical assessments were evaluated by NCI-CTC 4.0 grading and patient self-reported pain. RESULTS: Ten subjects were enrolled, nine were evaluable for safety and efficacy. Five of nine subjects reported some improvement in foot pain and three of eight subjects for hand pain improvement. One of these subjects noted specific improvement in tactile function. No treatment-related toxicities were observed. CONCLUSIONS: In this limited, single-center study, topical cream containing 1 % sildenafil is feasible to administer, is well-tolerated, and may mitigate PPE-related symptoms due to anti-cancer therapeutic agents. Further validation is necessary.


Subject(s)
Antineoplastic Agents/adverse effects , Hand-Foot Syndrome/drug therapy , Neoplasms/drug therapy , Piperazines/therapeutic use , Protein Kinase Inhibitors/therapeutic use , Sulfonamides/therapeutic use , Adult , Aged , Antineoplastic Agents/therapeutic use , Capecitabine , Deoxycytidine/adverse effects , Deoxycytidine/analogs & derivatives , Deoxycytidine/therapeutic use , Double-Blind Method , Female , Fluorouracil/adverse effects , Fluorouracil/analogs & derivatives , Fluorouracil/therapeutic use , Hand-Foot Syndrome/etiology , Humans , Indoles/adverse effects , Indoles/therapeutic use , Male , Middle Aged , Pilot Projects , Piperazines/administration & dosage , Piperazines/adverse effects , Placebos/administration & dosage , Protein Kinase Inhibitors/administration & dosage , Protein Kinase Inhibitors/adverse effects , Purines/administration & dosage , Purines/adverse effects , Purines/therapeutic use , Pyrroles/adverse effects , Pyrroles/therapeutic use , Sildenafil Citrate , Sulfonamides/administration & dosage , Sulfonamides/adverse effects , Sunitinib , Vascular Endothelial Growth Factor A/antagonists & inhibitors
3.
Invest New Drugs ; 32(2): 330-9, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24173967

ABSTRACT

PURPOSE: Dasatinib inhibits src family kinases and has anti-angiogenic properties. We conducted a phase I study of dasatinib, capecitabine, oxaliplatin, and bevacizumab (CapeOx/bevacizumab), with an expansion cohort in metastatic colorectal cancer (CRC). METHODS: Patients were enrolled in a dose escalation cohort to establish the maximum tolerated dose (MTD) and the recommended phase II dose (RP2D). Using a "3 + 3" design, twelve patients with advanced solid tumors received dasatinib (50 mg twice daily or 70 mg daily), capecitabine (850 mg/m(2) twice daily, days 1-14), oxaliplatin (130 mg/m(2) on day 1) and bevacizumab (7.5 mg/kg on day1), every 3 weeks. Ten patients with previously untreated metastatic CRC were then enrolled in an expansion cohort. Activated src (src(act)) expression was measured by immunohistochemistry, using an antibody that selectively recognizes the active conformation of src (clone 28). RESULTS: Twenty-two patients were enrolled between June 2009 and May 2011. Two DLTs were observed in the 50 mg bid dasatinib cohort, and one DLT was observed in the 70 mg daily dasatinib cohort. The MTD and RP2D for dasatinib was 70 mg daily. The most common treatment-related adverse events were fatigue (20; 91 %) and diarrhea (18; 82 %). Biomarker analysis of src(act) expression demonstrated that the overall response rate (ORR) was 75 % (6/8) for patients with high src(act) expression (IHC ≥ 2), compared to 0 % (0/8) for patients with low srcact expression (IHC 0 or 1); (p = 0.007). CONCLUSIONS: The RP2D of dasatinib is 70 mg daily in combination with CapeOx/bevacizumab. High levels of srcact expression may predict those patients most likely to benefit from dasatinib.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Colorectal Neoplasms/drug therapy , Adult , Aged , Angiogenesis Inhibitors/administration & dosage , Angiogenesis Inhibitors/adverse effects , Antibodies, Monoclonal, Humanized/administration & dosage , Antibodies, Monoclonal, Humanized/adverse effects , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Bevacizumab , Biomarkers, Tumor/blood , Capecitabine , Colorectal Neoplasms/metabolism , Dasatinib , Deoxycytidine/administration & dosage , Deoxycytidine/adverse effects , Deoxycytidine/analogs & derivatives , Female , Fluorouracil/administration & dosage , Fluorouracil/adverse effects , Fluorouracil/analogs & derivatives , Humans , Male , Maximum Tolerated Dose , Middle Aged , Organoplatinum Compounds/administration & dosage , Organoplatinum Compounds/adverse effects , Oxaliplatin , Protein Kinase Inhibitors/administration & dosage , Protein Kinase Inhibitors/adverse effects , Pyrimidines/administration & dosage , Pyrimidines/adverse effects , Thiazoles/administration & dosage , Thiazoles/adverse effects , Vascular Endothelial Growth Factor A/immunology , src-Family Kinases/metabolism
4.
Invest New Drugs ; 32(4): 700-9, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24711126

ABSTRACT

PURPOSE: To define maximum tolerated dose (MTD), toxicities, and pharmacodynamics of capecitabine, oxaliplatin, bevacizumab, and everolimus in advanced solid tumor patients. DESIGN: This was a standard "3 + 3" dose-escalation trial. All subjects received bevacizumab 7.5 mg/kg on day 1 of each cycle. Doses for capecitabine, oxaliplatin and everolimus were modified per dose limiting toxicity (DLT). Baseline and on-treatment plasma biomarkers were analyzed. Archived tumor mRNA levels were evaluated for NRP1, NRP2 and VEGF-A isoforms. RESULTS: Twenty-nine patients were evaluable for toxicity and 30 for efficacy. Two DLTs were observed in cohort 1 and one DLT each was observed in cohort -1 and -1b. Grade ≥3 toxicities included neutropenia, hypertension, perforation/fistula/hemorrhage, hypertriglyceridemia, diarrhea, and thromboembolism. Twelve subjects experienced partial response (PR); 12 had stable disease as best response. Three of seven chemorefractory metastatic colorectal cancer (mCRC) subjects experienced PR; 8 of 15 chemonaive mCRC subjects experienced PR. Plasma TßRIII and IL-6 increased on treatment but without correlation to outcome. Increased VEGF165 levels significantly correlated with longer progression free survival. CONCLUSIONS: Everolimus with full dose capecitabine, oxaliplatin, and bevacizumab had unacceptable toxicity. MTD was: everolimus 5 mg daily; capecitabine 680 mg/m(2) BID days 1-14; oxaliplatin 100 mg/m(2) and bevacizumab 7.5 mg/kg, day 1. Activity was noted in mCRC.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Neoplasms/drug therapy , Angiogenesis Inhibitors/administration & dosage , Angiogenesis Inhibitors/adverse effects , Antibodies, Monoclonal, Humanized/administration & dosage , Antibodies, Monoclonal, Humanized/adverse effects , Antimetabolites, Antineoplastic/administration & dosage , Antimetabolites, Antineoplastic/adverse effects , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/adverse effects , Bevacizumab , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Capecitabine , Deoxycytidine/administration & dosage , Deoxycytidine/adverse effects , Deoxycytidine/analogs & derivatives , Everolimus , Female , Fluorouracil/administration & dosage , Fluorouracil/adverse effects , Fluorouracil/analogs & derivatives , Humans , Immunosuppressive Agents/administration & dosage , Immunosuppressive Agents/adverse effects , Male , Maximum Tolerated Dose , Middle Aged , Neuropilin-1/genetics , Neuropilin-1/metabolism , Neuropilin-2/genetics , Neuropilin-2/metabolism , Organoplatinum Compounds/administration & dosage , Organoplatinum Compounds/adverse effects , Oxaliplatin , RNA, Messenger/genetics , RNA, Messenger/metabolism , Sirolimus/administration & dosage , Sirolimus/adverse effects , Sirolimus/analogs & derivatives , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor A/metabolism
5.
Oncologist ; 18(3): 271-2, 2013.
Article in English | MEDLINE | ID: mdl-23485624

ABSTRACT

BACKGROUND: Esophageal and gastric cancers often present at an advanced stage. Systemic chemotherapy is the mainstay of treatment, but survival with current regimens remains poor. We evaluated the safety, tolerability, and efficacy of the combination capecitabine, oxaliplatin, and bevacizumab in the treatment of metastatic esophagogastric adenocarcinomas. METHODS: Thirty-seven patients with metastatic or unresectable gastric/gastroesophageal junction tumors were enrolled and treated with capecitabine 850 mg/m(2) BID on days 1-14, and oxaliplatin 130 mg/m(2) with bevacizumab 15 mg/kg on day 1 of a 21-day cycle. The primary endpoint was progression-free survival (PFS). Secondary endpoints included response rate (RR) and overall survival (OS). Neuropilin-1 (NRP1) and -2 (NRP2) mRNA expression was evaluated in archived tumor. RESULTS: Thirty-five patients were evaluable for efficacy. Median PFS was 7.2 months; median OS was 10.8 months. RR was estimated at 51.4%. The regimen was tolerable with expected drug class-related toxicities. NRP2 mRNA levels significantly correlated with PFS (p = 0.042) and showed a trend toward significance with OS (p = 0.051). Nonsignificant trends for NRP1 were noted for higher expression levels and worse outcome. CONCLUSIONS: Bevacizumab can be given safely with chemotherapy in patients with metastatic esophagogastric adenocarcinomas. The combination of capecitabine, oxaliplatin, plus bevacizumab has activity comparable to other bevacizumab-containing regimens in metastatic gastroesophageal cancer.


Subject(s)
Adenocarcinoma/drug therapy , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Esophageal Neoplasms/drug therapy , Esophagogastric Junction/pathology , Stomach Neoplasms/drug therapy , Adenocarcinoma/pathology , Antibodies, Monoclonal, Humanized/administration & dosage , Antibodies, Monoclonal, Humanized/adverse effects , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Bevacizumab , Capecitabine , Deoxycytidine/administration & dosage , Deoxycytidine/adverse effects , Deoxycytidine/analogs & derivatives , Disease-Free Survival , Drug Administration Schedule , Esophageal Neoplasms/pathology , Fluorouracil/administration & dosage , Fluorouracil/adverse effects , Fluorouracil/analogs & derivatives , Humans , Organoplatinum Compounds/administration & dosage , Organoplatinum Compounds/adverse effects , Oxaliplatin , Stomach Neoplasms/pathology , Survival Analysis
6.
Cancer Invest ; 29(9): 617-25, 2011 Nov.
Article in English | MEDLINE | ID: mdl-22011284

ABSTRACT

We conducted a phase I study to assess safety, pharmacokinetics, pharmacodynamics, and activity of lonafarnib plus gemcitabine. Subjects received oral lonafarnib twice daily and gemcitabine on days 1, 8, and 15 every 28 days; multiple dose levels were explored. Lonafarnib had no apparent effect on gemcitabine PK. Mean lonafarnib half-life ranged from 4 to 7 hr; median T(max) values ranged from 4 to 8 hr. Two patients had partial response; seven patients had stable disease at least 6 months. Oral lonafarnib at 150 mg a.m./100 mg p.m. plus gemcitabine at 1,000 mg/m(2) is the maximum tolerated dose with acceptable safety and tolerability.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Neoplasms/drug therapy , Administration, Oral , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Deoxycytidine/administration & dosage , Deoxycytidine/adverse effects , Deoxycytidine/analogs & derivatives , Deoxycytidine/pharmacokinetics , Dose-Response Relationship, Drug , Female , Humans , Infusions, Intravenous , Male , Middle Aged , Neoplasms/metabolism , Piperidines/administration & dosage , Piperidines/adverse effects , Piperidines/pharmacokinetics , Pyridines/administration & dosage , Pyridines/adverse effects , Pyridines/pharmacokinetics , Gemcitabine
7.
Exp Mol Pathol ; 91(1): 434-9, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21497600

ABSTRACT

PURPOSE: Uterine leiomyomas (fibroids) are benign smooth muscle tumors commonly found among reproductive-aged women. Though benign, these tumors are the leading indication for hysterectomies in the United States and cause significant morbidity. Despite the importance of this tumor in women's health, relatively little is known about the molecular etiology. METHODS: In this study, we used the Affymetrix 100K single nucleotide polymorphism (SNP) chip to assess whether the pattern and frequency of genome-wide loss of heterozygosity (LOH) and copy number amplifications is associated with clinical heterogeneity. RESULTS: Thirty-seven tumors with varying sizes and histology from eleven patients were analyzed. LOH was observed in 4/37 tumors (10.8%) and significantly associated with large-sized tumors (p<0.0014). Two tumors revealed hemizygosity on chromosome 7q, a region that has been consistently reported to have LOH. Additionally, we detected one novel region of LOH, 16p13.11 in one tumor (2.7%). Copy number amplifications were observed on all chromosomes; however, most were low-level amplifications and only detected in a single tumor. One region of amplification at 3p26.3 was detected in four tumors. CONCLUSIONS: Despite the use of a high-density SNP platform, our results suggest that genome-wide LOH and copy number amplifications are infrequent events and generally do not determine clinical and histologic characteristics of this disease.


Subject(s)
DNA Copy Number Variations , Gene Dosage , Leiomyoma/genetics , Loss of Heterozygosity , Polymorphism, Single Nucleotide , Uterine Neoplasms/genetics , Chromosomes, Human, Pair 16 , Chromosomes, Human, Pair 3 , Chromosomes, Human, Pair 7 , Female , Gene Amplification , Genomics , Humans , Leiomyoma/pathology , Oligonucleotide Array Sequence Analysis , Uterine Neoplasms/pathology
8.
Proc Natl Acad Sci U S A ; 105(48): 18877-82, 2008 Dec 02.
Article in English | MEDLINE | ID: mdl-19020090

ABSTRACT

8-Oxoguanine (8OG) is efficiently bypassed by RNA polymerases in vitro and in bacterial cells in vivo, leading to mutant transcripts by directing incorporation of an incorrect nucleotide during transcription. Such transcriptional mutagenesis (TM) may produce a pool of mutant proteins. In contrast, transcription-coupled repair safeguards against DNA damage, contingent upon the ability of lesions to arrest elongating RNA polymerase. In mammalian cells, the Cockayne syndrome B protein (Csb) mediates transcription-coupled repair, and its involvement in the repair of 8OG is controversial. The DNA glycosylase Ogg1 initiates base excision repair of 8OG, but its influence on TM is unknown. We have developed a mammalian system for TM in congenic mouse embryonic fibroblasts (MEFs), either WT or deficient in Ogg1 (ogg(-/-)), Csb (csb(-/-)), or both. This system uses expression of the Ras oncogene in which an 8OG replaces guanine in codon 61. Repair of 8OG restores the WT sequence; however, bypass and misinsertion opposite this lesion during transcription leads to a constitutively active mutant Ras protein and activation of downstream signaling events, including increased phosphorylation of ERK kinase. Upon transfection of MEFs with replication-incompetent 8OG constructs, we observed a marked increase in phospho-ERK in ogg(-/-) and csb(-/-)ogg(-/-) cells at 6 h, indicating persistence of the lesion and the occurrence of TM. This effect is absent in WT and csb(-/-) cells, suggesting rapid repair. These studies provide evidence that 8OG causes TM in mammalian cells, leading to a phenotypic change with important implications for the role of TM in tumorigenesis.


Subject(s)
Guanine/analogs & derivatives , Mutagenesis , Transcription, Genetic , ras Proteins/metabolism , Animals , Cells, Cultured , DNA Damage , DNA Glycosylases/genetics , DNA Glycosylases/metabolism , DNA Repair , DNA Repair Enzymes/genetics , DNA Repair Enzymes/metabolism , Enzyme Activation , Fibroblasts/cytology , Fibroblasts/physiology , Guanine/pharmacology , Humans , Mice , Mice, Knockout , Poly-ADP-Ribose Binding Proteins , ras Proteins/genetics
9.
Cancer Chemother Pharmacol ; 79(3): 611-619, 2017 03.
Article in English | MEDLINE | ID: mdl-28238078

ABSTRACT

PURPOSE: To define the maximum tolerated dose (MTD), recommended phase II dose (RPTD), and assess safety and tolerability for the combination of pazopanib plus TH-302, an investigational hypoxia-activated prodrug (HAP), in adult patients with advanced solid tumors. METHODS: This was an open-label, non-randomized, single-center, phase I trial consisting 2 stages. Stage 1 was a standard "3 + 3" dose escalation design to determine safety and the RPTD for TH-302 plus pazopanib combination. Stage 2 was an expanded cohort to better describe the tolerability and toxicity profile at the MTD. Pazopanib was orally dosed at 800 mg daily on days 1-28 for all cohorts. TH-302 was administered intravenously on days 1, 8 and 15 of a 28-day cycle at doses of 340 mg/m2 (cohort 1) or 480 mg/m2 (cohort 2). Dose limiting toxicity (DLT) was assessed in the first 28-day cycle. Efficacy was assessed every 2 cycles. RESULTS: Thirty patients were enrolled between December 2011 and September 2013. In the dose escalation stage, 7 patients were enrolled in the 340 mg/m2 TH-302 cohort and 6 patients in the 480 mg/m2 TH-302 cohort. Ten patients were evaluable for DLT. DLTs included grade 2 intolerable esophagitis (n = 1) in the 340 mg/m2 TH-302 cohort, and grade 3 vaginal inflammation (n = 1) and grade 3 neutropenia with grade 3 thrombocytopenia (n = 1, same patient) in the 480 mg/m2 TH-302 cohort. The 340 mg/m2 TH-302 cohort was determined to be MTD and RPTD. The most common treatment-related adverse events were hematologic (anemia, neutropenia, and thrombocytopenia), nausea/vomiting, palmar-plantar erythrodysesthesia syndrome, constipation, fatigue, mucositis, anorexia, pain, and hypertension. Partial response (PR) was observed in 10% (n = 3) of patients, stable disease (SD) in 57% (n = 17), and progressive disease (PD) in 23% (n = 7). Due to toxicity, 3 patients were discontinued from study drug prior to first radiographic assessment but were included in these calculations. Disease control ≥6 months was observed in 37% of patients (n = 11). CONCLUSIONS: The RPTD for this novel combination is pazopanib 800 mg daily on days 1-28 plus TH-302 340 mg/m2 on days 1, 8 and 15 of each 28-day cycle. Preliminary activity was seen in treatment-refractory cancers and supports potential value of co-targeting tumor angiogenesis and tumor hypoxia.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Neoplasms/drug therapy , Adult , Aged , Aged, 80 and over , Angiogenesis Inhibitors/administration & dosage , Antineoplastic Agents/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Cohort Studies , Disease-Free Survival , Dose-Response Relationship, Drug , Drug Resistance, Neoplasm , Female , Humans , Indazoles , Karnofsky Performance Status , Male , Maximum Tolerated Dose , Middle Aged , Nitroimidazoles/administration & dosage , Phosphoramide Mustards/administration & dosage , Pyrimidines/administration & dosage , Sulfonamides/administration & dosage , Young Adult
10.
Nucleic Acids Res ; 31(19): 5560-7, 2003 Oct 01.
Article in English | MEDLINE | ID: mdl-14500818

ABSTRACT

Saccharomyces cerevisiae possesses two Escherichia coli endonuclease III homologs, NTG1 and NTG2, whose gene products function in the base excision repair pathway and initiate removal of a variety of oxidized pyrimidines from DNA. Although the glycosylase activity of these proteins has been well studied, the in vivo importance of the AP lyase activity has not been determined. Previous genetic studies have suggested that the AP lyase activities of Ntg1p and Ntg2p may be major contributors in the initial processing of abasic sites. We conducted a biochemical characterization of the AP lyase activities of Ntg1p and Ntg2p via a series of kinetic experiments. Such studies were designed to determine if Ntg1p and Ntg2p prefer specific bases located opposite abasic sites and whether these lesions are processed with a catalytic efficiency similar to Apn1p, the major hydrolytic AP endonuclease of yeast. Our results indicate that Ntg1p and Ntg2p are equally effective in processing four types of abasic site-containing substrates. Certain abasic site substrates were processed with greater catalytic efficiency than others, a situation similar to Apn1p processing of such substrates. These biochemical studies strongly support an important biological role for Ntg1p and Ntg2p in the initial processing of abasic sites and maintenance of genomic stability.


Subject(s)
Carbon-Oxygen Lyases/metabolism , N-Glycosyl Hydrolases/metabolism , Saccharomyces cerevisiae/enzymology , Catalysis , DNA/chemistry , DNA/metabolism , DNA Repair Enzymes , DNA-(Apurinic or Apyrimidinic Site) Lyase , Endodeoxyribonucleases/metabolism , Kinetics , Models, Chemical , N-Glycosyl Hydrolases/physiology , Saccharomyces cerevisiae Proteins/metabolism , Substrate Specificity
11.
Am J Med Genet ; 110(3): 226-33, 2002 Jul 01.
Article in English | MEDLINE | ID: mdl-12116230

ABSTRACT

Since the development of a molecular diagnosis for the fragile X syndrome in the early 1990s, several population-based studies in Caucasians of mostly northern European descent have established that the prevalence is probably between one in 6,000 to one in 4,000 males in the general population. Reports of increased or decreased prevalence of the fragile X syndrome exist for a few other world populations; however, many of these are small and not population-based. We present here the final results of a 4-year study in the metropolitan area of Atlanta, Georgia, establishing the prevalence of the fragile X syndrome and the frequency of CGG repeat variants in a large Caucasian and African-American population. Results demonstrate that one-quarter to one-third of the children identified with the fragile X syndrome attending Atlanta public schools are not diagnosed before the age of 10 years. Also, a revised prevalence for the syndrome revealed a higher point estimate for African-American males (1/2,545; 95% CI: 1/5,208-1/1,289) than reported previously, although confidence intervals include the prevalence estimated for Caucasians from this (1/3,717; 95% CI: 1/7,692-1/1,869) and other studies. Further population-based studies in diverse populations are necessary to explore the possibility that the prevalence of the fragile X syndrome differs among world populations.


Subject(s)
Black People/genetics , Fragile X Syndrome/genetics , RNA-Binding Proteins , Alleles , Child , Female , Fragile X Mental Retardation Protein , Fragile X Syndrome/epidemiology , Gene Frequency , Humans , Male , Mutation , Nerve Tissue Proteins/genetics , Prevalence , Trinucleotide Repeats/genetics , United States/epidemiology
12.
Article in English | MEDLINE | ID: mdl-23028128

ABSTRACT

The development and use of antiangiogenesis agents, particularly those targeting vascular endothelial growth factor (VEGF), has become an integral component of anticancer regimens for many tumor types. This review is intended to highlight some of the most important clinical successes and failures of anti-VEGF therapies, and where possible, to suggest important lessons that have been learned. This review emphasizes data from agents that have been FDA approved and/or have completed phase III studies.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Neoplasms/blood supply , Neovascularization, Pathologic/drug therapy , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Angiogenesis Inhibitors/adverse effects , Biomarkers, Tumor/metabolism , Drug Approval , Humans , Neoplasms/drug therapy , Neoplasms/pathology , Treatment Outcome
13.
Cancer Chemother Pharmacol ; 70(2): 251-8, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22744359

ABSTRACT

PURPOSE: To define the maximum tolerated dose, clinical toxicities, and pharmacodynamics of bevacizumab, everolimus, and panobinostat (LBH-589) when administered in combination to patients with advanced solid tumor malignancies. EXPERIMENT DESIGN: Subjects received 10 mg of panobinostat three times weekly, 5 or 10 mg everolimus daily, and bevacizumab at 10 mg/kg every 2 weeks. Dose-limiting toxicities (DLTs) were assessed in cycle 1; toxicity evaluation was closely monitored throughout treatment. Treatment continued until disease progression or undesirable toxicity. Protein acetylation was assessed in peripheral blood mononuclear cells (PBMC) both at baseline and on treatment. RESULTS: Twelve subjects were evaluable for toxicity and nine subjects for response. DLTs in cohort 1 included grade 2 esophagitis and grade 3 oral mucositis; DLTs in cohort -1 were grade 2 ventricular arrhythmia and grade 2 intolerable skin rash. Common adverse events were diarrhea (50 %), headache (33 %), mucositis/stomatitis (25 %), hyperlipidemia (25 %), and thrombocytopenia (25 %). There was 1 partial response; an additional 2 subjects had stable disease as best response. No consistent changes in protein acetylation in PBMC were observed in samples available from eight patients on treatment compared with baseline. CONCLUSIONS: Bevacizumab, everolimus, and panobinostat in combination at the lowest proposed doses did not have an acceptable safety and tolerability profile and did not consistently inhibit HDAC activity; therefore, we do not recommend further evaluation.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Neoplasms/drug therapy , Administration, Oral , Adult , Aged , Antibodies, Monoclonal, Humanized/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Bevacizumab , Dose-Response Relationship, Drug , Drug Administration Schedule , Everolimus , Female , Humans , Hydroxamic Acids/administration & dosage , Indoles , Injections, Intravenous , Leukocytes, Mononuclear/drug effects , Male , Maximum Tolerated Dose , Middle Aged , Neoplasms/blood , Neoplasms/pathology , Panobinostat , Sirolimus/administration & dosage , Sirolimus/analogs & derivatives , Treatment Outcome
14.
Cancer Chemother Pharmacol ; 70(1): 95-102, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22638798

ABSTRACT

PURPOSE: Preclinical data suggest concurrent inhibition of VEGF, mTOR and EGFR pathways may augment antitumor and antiangiogenic effects compared to inhibition of each pathway alone. This study evaluated the maximum tolerated dose/recommended phase II dose and safety and tolerability of bevacizumab, everolimus and panitumumab drug combination. METHODS: Subjects with advanced solid tumors received escalating doses of everolimus and flat dosing of panitumumab at 4.8 mg/kg and bevacizumab at 10 mg/kg every 2 weeks. Dose-limiting toxicities (DLTs) were assessed in cycle 1; toxicity evaluation was closely monitored throughout treatment. Treatment continued until disease progression or undesirable toxicity. RESULTS: Thirty-two subjects were evaluable for toxicity; 31 subjects were evaluable for tumor response. DLTs were observed in cohorts with everolimus at 10 and 5 mg daily and included grade 3 mucositis, skin rash and thrombocytopenia. Therefore, everolimus was dose-reduced to 5 mg three times weekly, which improved the tolerability of the treatment regimen. Common adverse events were skin rash/pruritus (91 %), mucositis/stomatitis (75 %), hypomagnesemia (72 %), hypocalcemia (56 %) and hypokalemia (50 %). There were 3 partial responses; an additional 10 subjects had stable disease ≥6 months. Three subjects with ovarian cancer and one with endometrial cancer achieved prolonged disease control ranging from 11 to >40 months. CONCLUSIONS: The recommended phase II dose is everolimus at 5 mg three times weekly plus panitumumab at 4.8 mg/kg and bevacizumab at 10 mg/kg every 2 weeks. This dosing regimen has an acceptable safety and tolerability profile and appears to have moderate the clinical activity in refractory tumors.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Neoplasms/drug therapy , Adult , Aged , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal, Humanized/administration & dosage , Antibodies, Monoclonal, Humanized/adverse effects , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Bevacizumab , Dose-Response Relationship, Drug , Drug Administration Schedule , Everolimus , Exanthema/chemically induced , Female , Humans , Hypocalcemia/chemically induced , Hypokalemia/chemically induced , Male , Middle Aged , Mucositis/chemically induced , Panitumumab , Sirolimus/administration & dosage , Sirolimus/adverse effects , Sirolimus/analogs & derivatives , Treatment Outcome , Young Adult
15.
Cancer Chemother Pharmacol ; 67(2): 455-63, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20972873

ABSTRACT

PURPOSE: This phase I study was performed to determine the safety profile, maximum tolerated dose (MTD) and biological activity of lonafarnib (SCH 66336). Single-dose and multi-dose pharmacokinetics were conducted. METHODS: Twenty-one patients with advanced solid tumors were enrolled. Each patient received single-dose administration on day 1, cycle 1 then switched to a twice daily (BID) dosing regimen on days 2-14 of a 28-day cycle; subsequent cycles continued BID dosing on days 1-14. Dose-limiting toxicity (DLT) was assessed during the cycle one; toxicity evaluation was closely monitored throughout the treatment. Radiographic scans were completed to assess tumor response. Blood and urine pharmacokinetics were evaluated on days 1 and 14 in cycle 1. SCH 66336- induced farnesylation inhibition was assessed via conversion of prelamin A to lamin in buccal mucosa. RESULTS: DLT and most common adverse events were diarrhea, fatigue, nausea and anorexia. No grade 3 or 4 hematological toxicities were observed. Nineteen of 21 patients were evaluable for response; short-term stable disease was observed in 5 patients. SCH 66336 systemic exposure increased with dose; however, drug accumulation was higher than projected. Renal excretion of parent drug was negligible. Farnesyl transferase inhibition was detected at the 200 and 300 mg BID doses. CONCLUSION: The MTD and recommended phase II dose is 200 mg BID on days 1-14 of a 28-day dosing regimen. The plasma concentration profile suggests the pharmacokinetics of SCH 66336 is dose and time dependent. Farnesyl transferase target inhibition was observed at doses of lonafarnib recommended for further study.


Subject(s)
Neoplasms/drug therapy , Piperidines/pharmacokinetics , Piperidines/therapeutic use , Pyridines/pharmacokinetics , Pyridines/therapeutic use , Adult , Aged , Alkyl and Aryl Transferases/antagonists & inhibitors , Alkyl and Aryl Transferases/metabolism , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Area Under Curve , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/therapeutic use , Female , Humans , Lamin Type A , Male , Maximum Tolerated Dose , Middle Aged , Mouth Mucosa/drug effects , Mouth Mucosa/metabolism , Neoplasms/mortality , Nuclear Proteins/metabolism , Piperidines/administration & dosage , Piperidines/adverse effects , Piperidines/pharmacology , Protein Precursors/metabolism , Pyridines/administration & dosage , Pyridines/adverse effects , Pyridines/pharmacology , Treatment Outcome
16.
Cancer Chemother Pharmacol ; 67(2): 465-74, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21079958

ABSTRACT

PURPOSE: VEGF, mTOR, and EGFR inhibitors have demonstrated anti-tumor and anti-angiogenic effects alone and in combination with each other. This study evaluated the safety, tolerability, and pharmacokinetics of bevacizumab, everolimus, and erlotinib combination. METHODS: Doublet therapy consisted of bevacizumab at 10 mg/kg every 14 days and everolimus 5 mg daily which escalated to 10 mg daily. Erlotinib 75 mg daily was added to the phase II dose recommended phase II dose (RPTD) of bevacizumab and everolimus. Dose-limiting toxicity (DLT) was assessed in cycle 1. RESULTS: Forty-eight patients with advanced solid malignancies were evaluable for DLT and efficacy. No DLTs were observed in the doublet dose escalation. Two DLTs (grade 3 mucositis and grade 3 rash) were observed with the addition of erlotinib 75 mg daily. Consequently, triplet doses were adjusted and were better tolerated. Four patients had a partial response. Median progression-free survival (PFS) for the doublet therapy was 6.0 months (0.5 to 32+ months) and 5.5 months (0.8 to 27+ months) for the triplet therapy. Systemic exposure of everolimus was significantly higher in combination with erlotinib (476 ± 161 ng h/mL) compared to when given alone (393 ± 156 ng h/mL; P = 0.020). CONCLUSIONS: The RPTD for the doublet therapy is bevacizumab 10 mg/kg every 14 days and everolimus 10 mg daily, and the RPTD for the triplet therapy is bevacizumab 5 mg/kg every 14 days, everolimus 5 mg and erlotinib 75 mg daily. Prolonged disease stability was demonstrated in tumors known to respond to mTOR inhibition and potentially resistant to VEGF blockade.


Subject(s)
Antibodies, Monoclonal/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Neoplasms/drug therapy , Neoplasms/pathology , Quinazolines/administration & dosage , Sirolimus/analogs & derivatives , Adult , Aged , Angiogenesis Inhibitors/administration & dosage , Angiogenesis Inhibitors/therapeutic use , Antibodies, Monoclonal/pharmacokinetics , Antibodies, Monoclonal, Humanized , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Bevacizumab , Disease-Free Survival , Erlotinib Hydrochloride , Everolimus , Female , Humans , Male , Maximum Tolerated Dose , Middle Aged , Protein Kinase Inhibitors/administration & dosage , Protein Kinase Inhibitors/pharmacokinetics , Protein Kinase Inhibitors/therapeutic use , Quinazolines/pharmacokinetics , Sirolimus/administration & dosage , Sirolimus/pharmacokinetics , Treatment Outcome
17.
Anticancer Res ; 30(4): 1251-6, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20530436

ABSTRACT

UNLABELLED: The aim of this study was to determine the maximally tolerated dose, recommended phase II dose and toxicity profile of capecitabine plus imatinib mesylate combination. PATIENTS AND METHODS: Twenty-four patients with advanced solid tumors were treated with capecitabine twice daily on days 1-14 and imatinib mesylate once daily on a 21-day cycle. Dose-limiting toxicity was assessed during the first cycle. Treatment continued until disease progression or undesirable toxicity. RESULTS: Six patients were treated with capecitabine at 1000 mg/m(2) and imatinib mesylate 300 mg; unacceptable toxicity due to grade 2 intolerable hand-foot syndrome and/or grade > or = 2 diarrhea was observed. Doses were subsequently reduced to capecitabine at 750 mg/m(2) and imatinib mesylate at 300 mg; toxicities were better tolerated at the lower dose. Dose-limiting toxicities consisted of grade 3 diarrhea, anorexia and fatigue lasting > or = 4 days. Treatment-related adverse events greater than or equal to grade 3 included anemia, diarrhea, dysuria, hypophosphatemia and vertigo. Minor responses were observed in two patients: stable disease > or = 6 months was observed in two out of twenty-one evaluable patients. CONCLUSION: Full doses of capecitabine and imatinib mesylate were not tolerable. The maximum tolerated dose and the recommended phase II dose for this drug combination is capecitabine at 750 mg/m(2) twice daily for 1-14 days and imatinib at 300 mg once daily on a 21-day cycle.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Neoplasms/drug therapy , Adult , Aged , Becaplermin , Benzamides , Capecitabine , Cohort Studies , Deoxycytidine/administration & dosage , Deoxycytidine/adverse effects , Deoxycytidine/analogs & derivatives , Drug Administration Schedule , Female , Fluorouracil/administration & dosage , Fluorouracil/adverse effects , Fluorouracil/analogs & derivatives , Humans , Imatinib Mesylate , Male , Middle Aged , Neoplasms/blood , Neoplasms/urine , Neovascularization, Physiologic/drug effects , Piperazines/administration & dosage , Piperazines/adverse effects , Platelet-Derived Growth Factor/metabolism , Proto-Oncogene Proteins c-sis , Pyrimidines/administration & dosage , Pyrimidines/adverse effects , Skin/blood supply
18.
Mol Cell Biol ; 29(3): 794-807, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19029246

ABSTRACT

DNAs harbored in both nuclei and mitochondria of eukaryotic cells are subject to continuous oxidative damage resulting from normal metabolic activities or environmental insults. Oxidative DNA damage is primarily reversed by the base excision repair (BER) pathway, initiated by N-glycosylase apurinic/apyrimidinic (AP) lyase proteins. To execute an appropriate repair response, BER components must be distributed to accommodate levels of genotoxic stress that may vary considerably between nuclei and mitochondria, depending on the growth state and stress environment of the cell. Numerous examples exist where cells respond to signals, resulting in relocalization of proteins involved in key biological transactions. To address whether such dynamic localization contributes to efficient organelle-specific DNA repair, we determined the intracellular localization of the Saccharomyces cerevisiae N-glycosylase/AP lyases, Ntg1 and Ntg2, in response to nuclear and mitochondrial oxidative stress. Fluorescence microscopy revealed that Ntg1 is differentially localized to nuclei and mitochondria, likely in response to the oxidative DNA damage status of the organelle. Sumoylation is associated with targeting of Ntg1 to nuclei containing oxidative DNA damage. These studies demonstrate that trafficking of DNA repair proteins to organelles containing high levels of oxidative DNA damage may be a central point for regulating BER in response to oxidative stress.


Subject(s)
Cell Nucleus/enzymology , DNA Repair , DNA-(Apurinic or Apyrimidinic Site) Lyase/metabolism , Mitochondria/enzymology , Oxidative Stress , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae/enzymology , Amino Acid Sequence , Antimycin A/analogs & derivatives , Antimycin A/pharmacology , Cell Compartmentation/drug effects , Cell Nucleus/drug effects , DNA Damage , DNA Repair/drug effects , DNA-(Apurinic or Apyrimidinic Site) Lyase/chemistry , Hydrogen Peroxide/pharmacology , Methyl Methanesulfonate/pharmacology , Mitochondria/drug effects , Models, Biological , Molecular Sequence Data , Mutant Proteins/metabolism , Oxygen/pharmacology , Protein Processing, Post-Translational/drug effects , Protein Transport/drug effects , Saccharomyces cerevisiae/cytology , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae/growth & development , Saccharomyces cerevisiae Proteins/chemistry , Small Ubiquitin-Related Modifier Proteins/metabolism , Subcellular Fractions/drug effects , Subcellular Fractions/enzymology
19.
Anticancer Res ; 29(12): 5149-53, 2009 Dec.
Article in English | MEDLINE | ID: mdl-20044630

ABSTRACT

AIM: To determine the maximally tolerated dose (MTD), recommended phase II dose (RPTD) and toxicity profile of gemcitabine plus irinotecan combination. PATIENTS AND METHODS: Thirty-nine evaluable patients with advanced solid tumors were treated with gemcitabine (Gem) and irinotecan (Iri) on days 1, 8 and 15 of a 28-day cycle. Dose levels included Gem/Iri 700/50, 900/50, 900/75, 500/50 mg/m(2) respectively. Dose-limiting toxicity (DLT) was assessed during cycle one; toxicity evaluation was closely monitored throughout the course of treatment. Treatment continued until disease progression or unacceptable toxicity. RESULTS: DLTs primarily consisted of grade > or = 3 thrombocytopenia lasting > or = 4 days often accompanied by grade > or = 3 neutropenia. Other grade > or = 3 toxicities included vomiting, diarrhea, fatigue and elevated alkaline phosphatase. Three patients had a partial response. Stable disease as best response was seen in 16 patients, ranging from 2-18 months. CONCLUSION: The MTD/RPTD is gemcitabine 500 mg/m(2) plus irinotecan 50 mg/m(2) on days 1, 8 and 15 of a 28-day cycle. Given the toxicity profile and negative results of phase III studies, no further testing of this treatment combination is recommended.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Neoplasms/drug therapy , Adult , Aged , Camptothecin/administration & dosage , Camptothecin/analogs & derivatives , Case-Control Studies , Deoxycytidine/administration & dosage , Deoxycytidine/analogs & derivatives , Dose-Response Relationship, Drug , Female , Humans , Irinotecan , Male , Maximum Tolerated Dose , Middle Aged , Neoplasm Staging , Neoplasms/pathology , Prognosis , Survival Rate , Gemcitabine
20.
Toxicol Pathol ; 35(1): 65-74, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17325974

ABSTRACT

Lung cancer is the leading cause of cancer deaths in both men and women in the United States. The LIFE (Light Induced Fluorescence Endoscopy) Project was initiated at the University of North Carolina Medical Center in November, 1999, for the dual purposes of (1) detecting pre-invasive lung cancer in high-risk patients and (2) studying the molecular biology of pre-invasive lesions of the bronchus for possible development of molecular biomarkers. Of the 47 patients enrolled, all were current or former tobacco smokers, except for 1. Fluorescence endoscopy was utilized, in addition to white light bronchoscopy, to increase the detection of intraepithelial lesions. Adjacent biopsies were submitted for permanent and frozen sections, respectively, from four predetermined sites as well as from any abnormal areas. The snap-frozen specimens were cryostat sectioned, and the mucosal epithelial cells laser capture microdissected for DNA analysis. The great majority of specimens yielded sufficiently abundant and intact DNA to accomplish the molecular objectives. Histologic concordance of adjacent permanent and frozen sections was equivalent to the concordance of adjacent permanent sections, suggesting that frozen section diagnosis was adequate for the research purpose of correlating histology with molecular analysis.


Subject(s)
Bronchoscopy/methods , Carcinoma in Situ/diagnosis , Fluorescence , Lasers , Lung Neoplasms/diagnosis , DNA, Neoplasm/analysis , Frozen Sections , Humans , Microdissection , Precancerous Conditions/diagnosis
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