Sequential mTOR inhibitor treatment with temsirolimus in metastatic renal cell carcinoma following failure of VEGF receptor tyrosine kinase inhibitors.

PURPOSE: Agents targeting the mammalian target of rapamycin (mTOR) pathway, e. g. everolimus, can provide clinical benefit in pretreated patients with metastatic renal cell carcinoma (mRCC), but data from randomized trials on the sequential use of temsirolimus are lacking. We retrospectively studied the efficacy and safety of temsirolimus therapy following failure of rTKI therapy. METHODS: Twenty-nine patients treated with temsirolimus (25 mg/week) following progression on rTKI therapy were studied at four institutions. All patients had failed at least one prior rTKI therapy (sunitinib, n = 6; sorafenib, n = 1; both, n = 22). Over 80% had two or more prior therapies. Data on efficacy (response assessment, progression-free survival [PFS], overall survival [OS]) and safety (NCI-CTC) were analyzed. RESULTS: Adverse events occurred in 90% of patients with the majority being grade 1 (n = 4, 14%) or grade 2 (n = 12, 41%). Most grade 3/4 toxicities (n = 10, 34%) were manageable and included anemia (n = 4, 14%), leukopenia/neutropenia (n = 2, 7%), hyperglycemia (n = 1, 3%), acidosis/alkalosis (n = 2, 7%), and infection (n = 1, 3%). One patient discontinued temsirolimus for grade 3 pneumonitis. Median (range) PFS and OS were 5.1 months (1-10.4) and 18.0 months (12.6-23.3), respectively. Best response included partial response (n = 1) and stable disease (n = 15) for a disease control rate of 55%, and disease progression of 45% (n = 13). CONCLUSIONS: Temsirolimus after rTKI failure appears to provide promising safety and efficacy comparable to other treatment options in pretreated patients with mRCC.

Sunitinib treatment for patients with advanced clear-cell renal-cell carcinoma after progression on sorafenib.

BACKGROUND: Sorafenib and sunitinib are tyrosine kinase inhibitors with largely overlapping specificities, approved for the treatment of metastatic renal-cell carcinoma (RCC). It was unclear whether the similarities of the two drugs would lead to complete cross-resistance, or whether sequential application would be efficacious. METHODS: Patients with metastatic RCC and progression on sorafenib treatment were treated with repeated cycles of sunitinib, 50 mg for 4 weeks, followed by a 2-week break. Response (Response Evaluation Criteria in Solid Tumors, RECIST) was assessed every second cycle. RESULTS: A total of 22 patients with progression on sorafenib were accrued. Initially, sorafenib treatment was efficacious in all patients, with 7 showing partial response (PR) and 15 stable disease (SD), and subsequent disease progression. With 4 PRs (18%) and 12 SD (55%) a disease control rate of 73% was achieved. The median progression-free survival (PFS) on sunitinib was 21.5 weeks; median overall survival (OS) was not reached. Estimated 1-year PFS and OS were 31 and 60%, respectively. There was no apparent relationship between response to sorafenib and outcome on sunitinib. CONCLUSION: In our cohort of patients with RCC and progression after initial efficacy of sorafenib, the efficacy data of second-line sunitinib were close to published results of first-line treatment, suggesting limited clinically relevant cross-resistance.

Proteomic analysis of protein expression in human tonsillar cancer: differentially expressed proteins characterize human tonsillar cancer.

BACKGROUND: Head and neck cancer continues to be one of the most common tumor entities worldwide. Within this group of malignancies, tonsillar squamous cell carcinoma represent approximately 15-20% of all intraoral and oropharyngeal carcinomas in the United States. Accurate and early stage diagnosis still remains a major challenge, as patients are often presented at an advanced stage of disease, causing a low overall survival rate. Thus, new diagnostic markers are highly desirable and could allow for a more reliable diagnosis, with further insights into carcinogenesis and tumor biology. Furthermore, these markers could be the basis for new therapeutic targets and early disease detection. To address these issues, we decided to use a global proteomic approach to characterize tonsillar squamous cell carcinoma. MATERIALS AND METHODS: A total of 19 tonsillar carcinoma samples and 12 benign controls acquired from the corresponding normal epithelium were analyzed by 2-D gel electrophoresis. 2-DE gels were silver stained and analyzed using the PDQuest analysis software (BioRad). Tumor specific spots were detected and identified by consecutive MALDI-TOF-MS or MS/MS polypeptide identification. RESULTS: In total, 70 proteins showed significant quantitative differences in protein expression, with 50 polypeptides accessible for identification. Of those 50 polypeptides, we were able to identify a total of 27 proteins and protein isoforms, significantly up- or down-regulated in tonsillar cancer samples. In addition to previously reported polypeptides in head and neck cancers, we were able to identify several new potential marker proteins in this study. CONCLUSION: Our results show that a combination of tonsillar cancer specific proteins can be used for histopathological diagnosis and may serve as a basis for discovering further biomarkers for early detection and prediction of response to treatment in the future.

From the genome to the proteome--biomarkers in colorectal cancer.

BACKGROUND AND AIMS: Colorectal cancer is the second leading cause of cancer-related death. Current clinical practice in colorectal cancer screening (fecal occult blood test, FOBT; colonoscopy) has contributed to a reduction of mortality. However, despite these screening programs, about 70% of carcinomas are detected at advanced tumor stages (UICC III/IV) presenting poor patient prognosis. Thus, innovative tools and methodologies for early cancer detection can directly result in improving patient survival rates. PATIENTS/METHODS: Biomedical research has advanced rapidly in recent years with the availability of technologies such as global gene and protein expression profiling. Comprehensive tumor profiling has become a field of intensive research aiming at identifying biomarkers relevant for improved diagnostics and therapeutics. RESULTS: In this paper, we report a comprehensive review of genomic, transcriptomic, and proteomic approaches for biomarker identification in tissue and blood with a main emphasis on two-dimensional gel-electrophoresis (2-DE) and mass spectrometry analyses. CONCLUSION: Proteomics-based technologies enable to distinguish the healthy patient from the tumor patient with high sensitivity and specificity and could greatly improve common classification systems and diagnostics. However, this progress has not yet been transferred from bench to bedside but could open the door to a more accurate and target specific personalized medicine with improved patient survival.