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Query: UMLS:C0009402 (colorectal cancer)
 53,228 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Regarding the evolution of the treatments of colorectal cancer during the last five years, it appears that numerous questions have to be considered with a strategic point of view. In order to avoid inclusion of a lot of patients in clinical patients, we urgently need the help of biology to give us arguments to choose one treatment or another. The fact that ten years after their approval, we are not able to select responders to oxaliplatin or irinotecan, confirm that this is difficult problem to solve. The contribution of biology to the prescription of drugs commonly used in colorectal cancer is discussed in this paper. There are already situations where the contribution of biology to clinical practice and prescription is not debatable : this is the case for the use of UGT1A1 status determination when using irinotecan and the determination of KRAS status for the prescription of panitumumab (and cetuximab in a few months). This individual adaptation is a dream that becomes reasonable when we look on the recent results concerning EGFR inhibitors, but a lot of work has to be done and it is not sure that biological assessment of the tumour will be able to solve all the problems. For instance, to determine predictive factors of response to angiogenesis inhibitors, it is likely that solutions will come from new techniques of imaging rather than from biology. However, new tools such as proteomics or metabolomics, as well as a better dialogue between clinician and biologist, will allow fast improvements. It must be emphasised that, for the first time in 2008, it is possible to prescribe targeted therapies to a specific "targeted" group of patients with metastatic colorectal cancer.
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PMID:[Is it possible to individualize prescription of medical treatment in colorectal cancer? The clinician point of view]. 1900 22

Several drugs have been developed and demonstrated similar efficacy in colorectal cancer treatment therefore with choice, time comes for decision. The biologist will have to provide the tools allowing to clarify this choice. Among the tools available, those of pharmacogenetics and pharmacogenomics appear most promising and recent examples allow to illustrate their clinical interest. The pharmacogenetics of anti-cancer agents presents a clinical characteristic, which requires to hold into account the genetic variations not only of host cells but also of those of the tumor cells. Among the most conclusive examples one is that of the prediction of severe neutropenia induced by the irinotecan among patients homozygous for * 28 allele of UGT1A1 enzyme which conjugates SN38 active compound of irinotecan, the other one is the presence of a KRAS mutated allele in tumor cell to predict resistance to anti EGFR antibodies in the treatment of colorectal metastatic cancer.
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PMID:[The biological point of view on pharmacogenetics of anticancer agents in colorectal cancer]. 1900 23

The majority of current major advances in the management of main human malignancies including breast, colorectum and head and neck result from the introduction of targeted therapies. An optimal application of targeted therapy needs a knowledge for the tumoral status of the target itself. It is also interesting to dispose of biological informations resulting from the interactions between treatment and target (biological proof of the concept). These informations are at the basis of the conception of new clinical protocols in oncology. In this context the role of molecular biology units is determinant. Examples of concrete applications of this strategy will be detailled particularly for the MINDACT Trial in breast cancer and for the KRAS status in the setting of EGFR targeting therapies in advanced colorectal cancer.
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PMID:[Design of new protocols. Role of molecular biology units?]. 1900 33

It is becoming increasingly evident that cancer stem cells play a vital role in development and progression of cancers and relapse following chemotherapy. The present study examines the presence of cancer stem-like cells (CSC) in adenomatous polyps and in normal appearing colonic mucosa in humans during aging. The number of polyps was found to increase linearly with advancing age (r(2)=0.92, p<0.02). Immunohistochemical analysis revealed co-localization of CSC markers CD44 and CD166 in colonic polyps. Real-time RT-PCR analysis of normal appearing mucosa from subjects with adenomatous polyps showed an age-related rise in CSC as evidenced by the increased expression of CD44, CD166 and ESA. A similar phenomenon was also observed for EGFR. In addition, the expression each CSC marker was found to be about 2-fold higher in subjects with 3-4 polyps than those with 1-2 polyps. In conclusion, our results show that colon cancer stem-like cells are present in the premalignant adenomatous polyps as well in normal appearing colonic mucosa. Moreover, our observation of the age-related rise in CSC in macroscopically normal colonic mucosa suggests a predisposition of the organ to developing colorectal cancer.
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PMID:Age-related increase in colorectal cancer stem cells in macroscopically normal mucosa of patients with adenomas: a risk factor for colon cancer. 1901 Mar 7

The incidence of colorectal carcinoma has increased among patients <40 years of age for unclear reasons. In this study, we describe the clinical, pathologic, and molecular features of colorectal carcinomas that developed in young patients. We compiled a study group of 24 patients <40 years of age with colorectal carcinoma, and 45 patients > or =40 years of age served as controls. Cases were evaluated for clinical risk factors of malignancy and pathologic features predictive of outcome. The tumors were immunohistochemically stained for O6-methylguanine methyltransferase, MLH-1, MSH-2, MSH-6, beta-catenin, chemokine (C-X-C motif) receptor 4, epidermal growth factor receptor, TP53, p16, survivin, and alpha-methylacyl-CoA racemase; assessed for microsatellite instability and mutations in beta-catenin, APC, EGFR, PIK3CA, KRAS, and BRAF; evaluated for micro-RNA expression (miR-21, miR-20a, miR-183, miR-192, miR-145, miR-106a, miR-181b, and miR-203); and examined for evidence of human papillomavirus infection. One study patient each had ulcerative colitis and hereditary nonpolyposis colorectal cancer. Ninety-two percent of tumors from young patients occurred in the distal colon (P=0.006), particularly the rectum (58%, P=0.02), and 75% were stage III or IV. Tumors from young patients showed more frequent lymphovascular (81%, P=0.03) and/or venous (48%, P=0.003) invasion, an infiltrative growth pattern (81%, P=0.03), and alpha-methylacyl-CoA racemase expression (83%, P=0.02) compared with controls. Carcinomas in this group showed significantly increased expression of miR-21, miR-20a, miR-145, miR-181b, and miR-203 (P< or =0.005 for all comparisons with controls). These results indicate that early-onset carcinomas commonly show pathologic features associated with aggressive behavior. Posttranslational regulation of mRNA and subsequent protein expression may be particularly important to the development of colorectal carcinomas in young patients.
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PMID:Clinical, pathologic, and molecular features of early-onset colorectal carcinoma. 1904 96

ErbBs signalling is always associated with the development of the majority of solid cancers via both the MAPK pathway leading to cell cycle progression and the PI3K pathway causing cell survival. As a consequence, many ErbB antagonists have been developed and patented for cancer treatment purposes. These antagonists belong to two drug classes: monoclonal antibodies (mAbs) and small molecules competing with ATP and inhibiting the tyrosine kinase domain (TKIs). Three patented mAbs are currently approved in clinical cancer treatment: Trastuzumab (Herceptin) directed against HER2 and used to treat breast cancer, Cetuximab and Panitumumab which are anti-EGFR antibodies approved for colorectal cancer treatment. Unfortunately, these mAbs are facing cancer resistance mediated by paracrine activation of other ErbB members or compensatory ErbB signalling factors. In parallel, three TKIs have been approved to treat cancer: Gefitinib (Iressa), Erlotinib (Tarceva) inhibiting specifically EGFR and approved to treat non small cell lung cancer and Lapatinib (Tykerb) which has the dual specificity EGFR/HER2 and recently approved to treat metastatic breast cancer. These TKIs are also facing resistance mutations within the TK domain which increase its affinity to ATP. Resistance problems are leading to the adoption of a new strategy based on the combination of different therapies and this is likely to be the most promising future of cancer treatments.
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PMID:ErbB antagonists patenting: "playing chess with cancer". 1907 65

Colorectal cancer remains one of the major causes of cancer death. Recent identification of new molecular targets led to the development of novel agents directed against growth factor receptors or key factors of angiogenesis. Recent phase III trials demonstrated a significant clinical benefit with bevacizumab, a VEGF inhibitor, and with EGFR-inhibitors, namely cetuximab and panitumumab. In this article we review the diverse treatment options combining cytotoxic and targeted therapies available for patients with metastatic colorectal cancer.
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PMID:[What are the new therapeutic strategies in metastatic colorectal cancer including biotherapies?]. 1923 Oct 39

Cancers in the gastrointestinal system account for a large proportion of malignancies and cancer-related deaths with gastric cancer and colorectal cancer being the most common ones. For those patients in whom surgical resection is not possible, other therapeutic approaches are necessary. Disordered apoptosis has been linked to cancer development and treatment resistance. Apoptosis occurs via extrinsic or intrinsic signaling each triggered and regulated by many different molecular pathways. In recent years, the selective induction of apoptosis in tumor cells has been increasingly recognized as a promising approach for cancer therapy. A detailed understanding of the molecular pathways involved in the regulation of apoptosis is essential for developing novel effective therapeutic approaches. Apoptosis can be induced by many different approaches including activating cell surface death receptors (for example, Fas, TRAIL and TNF receptors), inhibiting cell survival signaling (such as EGFR, MAPK and PI3K), altering apoptosis threshold by modulating pro-apoptotic and anti-apoptotic members of the Bcl-2 family, down-regulating anti-apoptosis proteins (such as XIAP, survivin and c-IAP2), and using other pro-apoptotic agents. In this review, the authors reviewed the currently reported apoptosis-targeting approaches in gastrointestinal cancers.
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PMID:Targeting apoptosis as an approach for gastrointestinal cancer therapy. 1927 96

Cetuximab and panitumumab efficacy in metastatic colorectal cancer (mCRC) may be influenced by EGFR gene status and/or deregulation of its downstream signalling proteins detected in primary tumour. However, metastasis might have different molecular patterns with respect to primary tumour, possibly affecting the prediction of EGFR-targeted therapy efficacy. We analysed primary tumour and metastasis in 38 mCRC patients. Twelve cases were cetuximab/panitumumab treated. EGFR gene status and protein expression were investigated through fluorescent in situ hybridisation and immunohistochemistry (IHC), K-Ras/BRAF mutations by sequencing and PTEN expression by IHC. We observed EGFR gene deregulation in 25 out of 36 primary tumours and 29 out of 36 metastases, K-Ras mutations in 16 out of 37 cancers and in 15 out of 37 metastases, BRAF mutations in 2 out of 36 cancers and 2 out of 36 metastases and PTEN loss in 8 out of 38 cancers and 12 out of 38 metastases. For the first time in literature, we show that primary colorectal cancer and paired metastasis may exhibit difference with respect to EGFR pathway deregulation mechanisms possibly implying a different response to cetuximab or panitumumab treatment. The investigation of treated patients confirms this hypothesis. We therefore suggest that the analysis of metastatic lesion should be considered in patient management as well as in designing future clinical trials aimed to investigate the effect of anti-EGFR monoclonal antibodies in the treatment of mCRC.
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PMID:Differing deregulation of EGFR and downstream proteins in primary colorectal cancer and related metastatic sites may be clinically relevant. 1958 70

Among the many chemotherapeutic options for metastatic colorectal cancer, none has shown clear superiority in efficacy. All pharmacologic agents in current use have been associated with adverse events. Frequently reported adverse events associated with the chemotherapeutic agents oxaliplatin, irinotecan, 5-fluorouracil, and capecitabine include acute and chronic neuropathy, hypersensitivity reactions, diarrhea, neutropenia, and hand-foot syndrome. Although biologic agents are seemingly less toxic, toxic effects can also arise with their use; antiangiogenic agents result in hypertension, and EGFR inhibitors can cause severe hypersensitivity, paronychial infections, and more commonly, dermatologic rash. Furthermore, a correlation has been reported for the efficacy of anti-EGFR agents and development of rash. Data indicate that elderly patients with colorectal cancer who have adequate function and performance status, who may previously have been dissuaded from pursuing active therapy solely on the basis of age, should receive the same treatment as younger patients. To enhance the survival of patients with metastatic colorectal cancer, many therapies are administered. Recognition of treatment-emergent toxic effects will, therefore, aid the design and implementation of management strategies that minimize treatment interruption and/or discontinuation, and enhance quality of life for patients.
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PMID:Toxic effects and their management: daily clinical challenges in the treatment of colorectal cancer. 1933 27


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