Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0006826 (cancer)
 1,092,456 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Renal cell carcinoma accounts for approximately 3% of adult malignancies and 90%-95% of neoplasms arising from the kidney. It is characterized by a lack of early warning signs, diverse clinical manifestations, resistance to radiation and chemotherapy, and infrequent but reproducible responses to immunotherapy with agents such as interferon alpha (IFNa) and interleukin 2 (IL-2). International studies have shown objective response rates of < 15% in patients with advanced and metastatic disease, with 5-year disease-specific survival ranging between 0-20%. Considering these poor outcomes, renal cancers' very vascular nature and overexpression of receptors for vascular endothelial growth factor (VEGF), various biologic and angio-suppressive therapies are being evaluated in clinical trials. Promising results in terms of overall response rate and median time to progression have been reported especially as second-line therapy following cytokine failure, a setting where no effective systemic therapy has been recognized (SU011248, Bay 43-9006, Bevacizumab and Erlotinib). While confirmatory studies are ongoing, other novel treatments in first line trials (CCI-779, Infliximab, PTK-787, and Thalidomide) have drawn international attention. This review, analyzing basic translational research principles, will summarize the available data on the use of these new therapeutic approaches in RCC.
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PMID:New treatments for metastatic kidney cancer. 1578 Jan 70

Erlotinib (Tarceva) is an orally available HER1 (epidermal growth factor receptor, EGFR) tyrosine kinase inhibitor advancing through clinical trials for the treatment of a range of human malignancies. In this study, we examine the capacity of erlotinib to modulate radiation response and investigate specific mechanisms underlying these interactions in human tumor cell lines and xenografts. The impact of erlotinib on cell cycle kinetics was analyzed using flow cytometry, and the impact on apoptosis was evaluated via fluorescein-labeled pan-caspase inhibition and poly(ADP-ribose) polymerase cleavage. Radiation-induced EGFR autophosphorylation and Rad51 expression were examined by Western blot analysis. Radiation survival was analyzed using a clonogenic assay and assessment of in vivo tumor growth was done using a mouse xenograft model system. Microarray studies were carried out using 20 K human cDNA microarray and select genes were validated using quantitative reverse transcription-PCR (RT-PCR). Independently, erlotinib and radiation induce accumulation of tumor cells in G(1) and G(2)-M phase, respectively, with a reduction of cells in S phase. When combined with radiation, erlotinib promotes a further reduction in S-phase fraction. Erlotinib enhances the induction of apoptosis, inhibits EGFR autophosphorylation and Rad51 expression following radiation exposure, and promotes an increase in radiosensitivity. Tumor xenograft studies confirm that systemic administration of erlotinib results in profound tumor growth inhibition when combined with radiation. cDNA microarray analysis assessing genes differentially regulated by erlotinib following radiation exposure identifies a diverse set of genes deriving from several functional classes. Validation is confirmed for several specific genes that may influence radiosensitization by erlotinib including Egr-1, CXCL1, and IL-1beta. These results identify the capacity of erlotinib to enhance radiation response at several levels, including cell cycle arrest, apoptosis induction, accelerated cellular repopulation, and DNA damage repair. Preliminary microarray data suggests additional mechanisms underlying the complex interaction between EGFR signaling and radiation response. These data suggest that the erlotinib/radiation combination represents a strategy worthy of further examination in clinical trials.
Cancer Res 2005 Apr 15
PMID:Mechanisms of enhanced radiation response following epidermal growth factor receptor signaling inhibition by erlotinib (Tarceva). 1583 66

Specific and reversible EGFR tyrosine kinase inhibitors (TKI) such as gefitinib and erlotinib are clinically active in advanced or metastatic NSCLC and both are approved in various countries for the treatment of patients that failed prior chemotherapy. Erlotinib has also prolonged survival in pancreatic cancer patients when added to gemcitabine and regulatory approval in this disease is being sought. Additional promising activity has been seen in other tumor types, such as ovarian cancer or head and neck malignancies, and phase III trials in these malignancies are ongoing or planned. Despite these successes, these agents have exhibited anecdotal or modest activity when used as single agents in unselected patients with various other tumor types. We have learned that the clinical development of these agents is far from simple and we need to better understand biological and clinical criteria for patient selection and how to best use the different available agents. The recent discovery of EGFR mutations and the potential identification of other markers that might predict patient response could help to optimize the use of these agents in the future. Irreversible EGFR inhibitors, dual EGF/HER2 and pan-ErbB receptor inhibitors may have greater antitumor activity although the tolerance of these compounds compared to specific EGFR TKIs needs further characterization. HER2 specific TKIs are also in development. Lapatinib, a dual EGFR/HER2 TK inhibitors, is particularly promising in breast cancer. Newer agents, such as BMS-599626, have recently entered into the clinic. In addition to the use of these agents as single agents, many clinical studies are addressing the role of combining them with hormonal agents, biological agents or chemotherapy.
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PMID:Small molecules with EGFR-TK inhibitor activity. 1585 87

Angiogenesis is a strongly regulated process, which is dependent upon a complex interplay between inhibitory and stimulatory angiogenic factors. It is essential for tumor growth and metastasis: increased angiogenesis is correlated with poor prognosis in cancer patients. Many novel compounds that potently inhibit formation of neoplastic blood vessels have been recently developed. Major categories of angiogenesis antagonists include protease inhibitors, direct inhibitors of endothelial cell proliferation and migration, angiogenic growth factor suppressors, inhibitors of endothelial-specific integrin/survival signalling, copper chelators, and inhibitors with other specific mechanisms. There is increasing interest in developing angio-suppressive agents for colorectal cancer treatment. Some 20 direct and indirect antiangiogenesis drugs are currently being evaluated in clinical trials in colorectal cancer (CRC). Promising results have been reported. These include an increase in overall survival and reduction in the risk of death (Bevacizumab), reversal of cellular resistance (Cetuximab) and activity as second-line therapy in patients who have exhausted other available treatment options (Cetuximab, ABX-EGF, PTK-787, Gefitinib, Erlotinib). This review will outline the mechanisms of action of the principal antiangiogenic drugs, summarize the available data on the use of these new drugs in colorectal cancer, discuss their impact in clinical practice and offer a glimpse into how antiangiogenetic therapy will be integrated into the future care of patients with gastrointestinal cancers.
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PMID:Colorectal cancer and antiangiogenic therapy: what can be expected in clinical practice? 1589 May 25

Receptor and non-receptor tyrosine kinases (TKs) have emerged as clinically useful drug target molecules for treating gastrointestinal cancer. Imatinib mesilate (STI-571, Gleevec(TM)), an inhibitior of bcr-abl TK, which was primarily designed to treat chronic myeloid leukemia is also an inhibitor of c-kit receptor TK, and is currently the drug of choice for the therapy of metastatic gastrointestinal stromal tumors (GISTs), which frequently express constitutively activated forms of the c-kit-receptor. The epidermal growth factor receptor (EGFR), which is involved in cell proliferation, metastasis and angiogenesis, is another important target. The two main classes of EGFR inhibitors are the TK inhibitors and monoclonal antibodies. Gefitinib (ZD1839, Iressa(TM)) has been on trial for esophageal and colorectal cancer (CRC) and erlotinib (OSI-774, Tarceva(TM)) on trial for esophageal, colorectal, hepatocellular, and biliary carcinoma. In addition, erlotinib has been evaluated in a Phase III study for the treatment of pancreatic cancer. Cetuximab (IMC-C225, Erbitux(TM)), a monoclonal EGFR antibody, has been FDA approved for the therapy of irinotecan resistant colorectal cancer and has been tested for pancreatic cancer. Vascular endothelial growth factor (VEGF) and its receptor (VEGFR) are critical regulators of tumor angiogenesis. Bevacizumab (Avastin(TM)), a monoclonal antibody against VEGF, was efficient in two randomized clinical trials investigating the treatment of metastatic colorectal cancer. It is also currently investigated for the therapy of pancreatic cancer in combination with gemcitabine. Other promising new drugs currently under preclinical and clinical evaluation, are VEGFR2 inhibitor PTK787/ZK 222584, thalidomide, farnesyl transferase inhibitor R115777 (tipifarnib, Zarnestra(TM)), matrix metalloproteinase inhibitors, proteasome inhibitor bortezomib (Velcade(TM)), mammalian target of rapamycin (mTOR) inhibitors, cyclooxygenase-2 (COX-2) inhibitors, platelet derived growth factor receptor (PDGF-R) inhibitors, protein kinase C (PKC) inhibitors, mitogen-activated protein kinase kinase (MEK) 1/2 inhibitors, Rous sarcoma virus transforming oncogene (SRC) kinase inhibitors, histondeacetylase (HDAC) inhibitors, small hypoxia-inducible factor (HIF) inhibitors, aurora kinase inhibitors, hedgehog inhibitors, and TGF-beta signalling inhibitors.
Curr Cancer Drug Targets 2005 May
PMID:Molecularly targeted therapy for gastrointestinal cancer. 1589 18

Interferon-alpha (IFNalpha) treatment is associated with up-regulation of epidermal growth factor receptor (HER1/EGFR) expression and marked growth inhibition while maintaining the sensitivity of the target colon cancer cells to epidermal growth factor (Gut 2004;53:123). We aimed to determine the effect of combining IFNalpha and Erlotinib (an HER1/EGFR inhibitor) on colon cancer cell line growth. Crystal-violet staining and flow cytometry were used to assess cell proliferation and expression of HER1/EGFR. IFNalpha pre-treatment followed by a combination of IFNalpha plus Erlotinib significantly enhanced the sensitivity of 7/9 of colon cancer cell lines by 7-43%. This approach may have clinical implications for improving treatment based on targeting of HER1/EGFR.
Cancer Lett 2005 Jul 08
PMID:Interferon-alpha promotes the anti-proliferative effect of Erlotinib (OSI-774) on human colon cancer cell lines. 1592 58

Erlotinib (Tarceva, OSI-774; Pfizer, Inc.) is an orally-active, targeted inhibitor of the epidermal growth factor receptor (EGFR/HER1), which is part of a key regulatory pathway in cancer. Patients with advanced, incurable non-small cell lung cancer (NSCLC) may derive a clinical benefit from first- and second-line chemotherapy, but third-line treatment with available cytotoxic agents is not effective. Remarkably, EGFR/HER1 antagonists have demonstrated activity as second- and even third-line treatment for this disease. Erlotinib is the first of this novel class of drug to demonstrate a statistically significant and clinically relevant difference in overall survival, progression free survival and time to disease related symptoms (cough, pain, shortness of breath) compared with treatment with best supportive care in patients who have failed standard first- or second-line chemotherapy. This paper reviews the pharmacology, preclinical and clinical data to support the use of erlotinib in NSCLC.
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PMID:Erlotinib in non-small cell lung cancer: a review. 1595 27

Cancer chemotherapy has been one of the major medical advances in the last few decades. However, the drugs used for this therapy have a narrow therapeutic index, and often the responses produced are only just palliative as well as unpredictable. In contrast, targeted therapy that has been introduced in recent years is directed against cancer-specific molecules and signaling pathways and thus has more limited nonspecific toxicities. Tyrosine kinases are an especially important target because they play an important role in the modulation of growth factor signaling. This review focuses on small molecule inhibitors of tyrosine kinase. They compete with the ATP binding site of the catalytic domain of several oncogenic tyrosine kinases. They are orally active, small molecules that have a favorable safety profile and can be easily combined with other forms of chemotherapy or radiation therapy. Several tyrosine kinase inhibitors (TKIs) have been found to have effective antitumor activity and have been approved or are in clinical trials. The inhibitors discussed in this manuscript are imatinib mesylate (STI571; Gleevec), gefitinib (Iressa), erlotinib (OSI-1774; Tarceva), lapatinib (GW-572016), canertinib (CI-1033), semaxinib (SU5416), vatalanib (PTK787/ZK222584), sorafenib (BAY 43-9006), sutent (SU11248), and leflunomide (SU101). TKIs are thus an important new class of targeted therapy that interfere with specific cell signaling pathways and thus allow target-specific therapy for selected malignancies. The pharmacological properties and anticancer activities of these inhibitors are discussed in this review. Use of these targeted therapies is not without limitations such as the development of resistance and the lack of tumor response in the general population. The availability of newer inhibitors and improved patient selection will help overcome these problems in the future.
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PMID:Role of tyrosine kinase inhibitors in cancer therapy. 1600 63

In many solid tumors, overexpression of human epidermal growth factor receptors (e.g., HER1/EGFR and HER2) correlates with poor prognosis. Erlotinib (Tarceva) is a potent HER1/EGFR tyrosine kinase inhibitor. Pertuzumab (Omnitarg), a novel HER2-specific, recombinant, humanized monoclonal antibody, prevents heterodimerization of HER2 with other HERs. Both mechanisms disrupt signaling pathways, resulting in tumor growth inhibition. We evaluated whether inhibition of both mechanisms is superior to monotherapy in tumor cell lines expressing different HER levels. Human non-small cell lung cancer (NSCLC) cells (Calu-3: HER1/EGFR 0+, HER2 3+; QG56: HER1/EGFR 2-3+, HER2 0+) and breast cancer cells (KPL-4: HER1/EGFR 2-3+, HER2 3+) were implanted into BALB/c nu/nu mice and severe combined immunodeficient beige mice, respectively. Tumor-bearing mice (n = 12 or 15 per group) were treated with vehicle (Captisol or buffer), erlotinib (orally, 50 mg/kg/d), pertuzumab (i.p. 6 mg/kg/wk with a 2-fold loading dose), or erlotinib and pertuzumab for 20 (QG56), 27 (KPL-4), or 49 (Calu-3) days. Drug monotherapy had antitumor activity in all models. Tumor volume treatment-to-control ratios (TCR) with erlotinib were 0.36 (Calu-3), 0.79 (QG56), and 0.51 (KPL-4). Pertuzumab TCR values were 0.42, 0.51, and 0.64 in Calu-3, QG56, and KPL-4 models, respectively. Combination treatment resulted in additive (QG56: TCR 0.39; KPL-4: TCR 0.38) or greater than additive (Calu-3: TCR 0.12) antitumor activity. Serum tumor markers for NSCLC (Cyfra 21.1) and breast cancer (soluble HER2) were markedly inhibited by combination treatment (80-97% in Calu-3 and QG56; 92% in KPL-4), correlating with decreased tumor volume. Overall, erlotinib and pertuzumab are active against various human xenograft models, independently of HER1/EGFR or HER2 expression. A combination of these HER-targeted agents resulted in additive or greater than additive antitumor activity.
Clin Cancer Res 2005 Jul 15
PMID:Combination treatment with erlotinib and pertuzumab against human tumor xenografts is superior to monotherapy. 1603 49

Over the past few years, two epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), gefitinib (Iressa) and erlotinib (Tarceva), have been developed for the treatment of patients with cancer. In patients with non-small cell lung cancer (NSCLC), these therapies occasionally demonstrate remarkable and durable activity. However, EGFR TKIs are active in only a small subset of patients. Responders are more often nonsmokers, of East Asian descent, and female, and have tumors with adenocarcinoma histology. In April 2004, two groups reported that a cluster of somatic mutations in the kinase domain of the EGFR are observed in the majority of NSCLCs that demonstrate remarkable responses to EGFR TKIs. These findings have been validated by other investigators and have revolutionized the manner in which clinicians are thinking about their utilization for the treatment of NSCLC. This review focuses on the clinical experience with EGFR TKIs, the present knowledge regarding the biology of EGFR mutations, the limitations of using EGFR mutational status to predict who will respond to EGFR TKIs, and the implications of this information on the use of these agents for the treatment of advanced NSCLC.
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PMID:Factors predicting response to EGFR tyrosine kinase inhibitors. 1605 33


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