1. |
- Bettegowda, Chetan, et al.
(author)
-
Detection of circulating tumor DNA in early- and late-stage human malignancies
- 2014
-
In: Science Translational Medicine. - : American Association for the Advancement of Science (AAAS). - 1946-6234 .- 1946-6242. ; 6:224, s. 224ra24-
-
Journal article (peer-reviewed)abstract
- The development of noninvasive methods to detect and monitor tumors continues to be a major challenge in oncology. We used digital polymerase chain reaction-based technologies to evaluate the ability of circulating tumor DNA (ctDNA) to detect tumors in 640 patients with various cancer types. We found that ctDNA was detectable in >75% of patients with advanced pancreatic, ovarian, colorectal, bladder, gastroesophageal, breast, melanoma, hepatocellular, and head and neck cancers, but in less than 50% of primary brain, renal, prostate, or thyroid cancers. In patients with localized tumors, ctDNA was detected in 73, 57, 48, and 50% of patients with colorectal cancer, gastroesophageal cancer, pancreatic cancer, and breast adenocarcinoma, respectively. ctDNA was often present in patients without detectable circulating tumor cells, suggesting that these two biomarkers are distinct entities. In a separate panel of 206 patients with metastatic colorectal cancers, we showed that the sensitivity of ctDNA for detection of clinically relevant KRAS gene mutations was 87.2% and its specificity was 99.2%. Finally, we assessed whether ctDNA could provide clues into the mechanisms underlying resistance to epidermal growth factor receptor blockade in 24 patients who objectively responded to therapy but subsequently relapsed. Twenty-three (96%) of these patients developed one or more mutations in genes involved in the mitogen-activated protein kinase pathway. Together, these data suggest that ctDNA is a broadly applicable, sensitive, and specific biomarker that can be used for a variety of clinical and research purposes in patients with multiple different types of cancer.
|
|
2. |
- De Fazio, Salvatore, et al.
(author)
-
Role of CYP3AS in abnormal clearance of methadone
- 2008
-
In: The Annals of Pharmacotherapy. - 1060-0280 .- 1542-6270. ; 42:6, s. 893-897
-
Journal article (peer-reviewed)abstract
- OBJECTIVE: To report a case of unusually low concentrations of methadone in a polydrug abuser during maintenance treatment with methadone. CASE SUMMARY: A 25-year-old man (weight 55 kg, height 165 cm) with a 12-year history of polydrug abuse was admitted to an opiates withdrawal methadone program. At the time of our observation, he was using both cannabinoids and heroin; no other medical conditions were discovered. Within the opiates withdrawal methadone program, under medical supervision, the patient started methadone therapy (20 mg/day). Two weeks later, an Abuscreen assay for methadone screening in the urine was negative and, to prevent the development of withdrawal symptoms, the dose of methadone was increased to 60 mg/day. One day later, the patient was asked to collect another urine sample in the presence of a nurse. The Abuscreen for methadone in urine remained negative. Evaluation of urinary samples collected over 24 hours documented low concentrations of methadone and high levels of 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (the primary metabolite of methadone). Evaluation for the presence of the most common polymorphisms in the cytochrome P450 and P-glycoprotein genes showed that the patient was heterozygous for the CYP3A5*1 allele and for 2 single nucleotide polymorphisms in the P-glyooprotein gene (1236C/T and 3435C/T). DISCUSSION: In this patient, poor methadone adherence was ruled out because of the presence of physicians and nurses during both methadone maintenance treatment and Abuscreen screening. Moreover, because the patient reported only heroin and cannabis at the time of evaluation, drug interactions were ruled out as possible causes for the rapid clearance of methadone. CONCLUSIONS: In this case, CYP3A5 polymorphism may have played a role in the rapid methadone metabolism.
|
|
3. |
- Zwierzina, Heinz, et al.
(author)
-
Molecularly targeted therapies for colorectal cancer: Strategies for implementing translational research in clinical trials
- 2010
-
In: CURRENT OPINION IN MOLECULAR THERAPEUTICS. - : Thomson Scientific. - 1464-8431. ; 12:6, s. 703-711
-
Research review (peer-reviewed)abstract
- Few breakthroughs in preclinical research have translated into meaningful benefits, either in clinical terms or quality of life, for patients with advanced colorectal cancer, despite important preclinical discoveries regarding aberrant biological pathways associated with disease development and progression. The many reasons for the slow progress are diverse, ranging from the failure to codevelop biomarkers and targeted therapies, the regulatory burdens imposed on academic investigators, and the failure to collect serial tumor biopsies during clinical trials. This review discusses promising translational research that could help reduce the disparity between preclinical discovery and patient benefit, and advocate the concentration of efforts and resources on the most promising therapeutic targets in colorectal cancer, such as EGFR, VEGF and Fc gamma receptor.
|
|