Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0178874 (tumor progression)
 40,807 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Barrett's esophagus develops as a complication of regurgitant esophagitis and predisposes patients to the development of dysplasia and esophageal adenocarcinoma. Prior ultrastructural studies have suggested that Barrett's epithelium is a mucous secretory epithelium that shares some morphologic features with the intestine. The origin and development of Barrett's epithelium and the cellular abnormalities accompanying its neoplastic progression are poorly understood. In an attempt to better understand the histogenesis of the mucus-producing cells that predominate in Barrett's epithelium, these cells were studied by transmission electron microscopy and compared with other upper gastrointestinal epithelia: esophageal glands, normal gastric surface, pit, and cardiac gland regions, gastric intestinal metaplasia, and normal jejunal villous tip and crypt regions. A total of 134 mucosal biopsies from the stomach and esophagus of 28 patients with Barrett's esophagus and 37 biopsies from 14 other control patients were studied. Barrett's specialized metaplastic surface cells display a spectrum of ultrastructural features among three main surface columnar epithelial cell types: mucous cells resembling those seen in the normal gastric surface epithelium or resembling mucous neck cells normally seen in the gastric pits; goblet cells similar to those seen in the jejunum; and "pseudoabsorptive" cells with features of both gastric mucous secretory cells and jejunal absorptive cells. Cytoplasmic organelles of Barrett's specialized metaplastic, normal gastric mucous neck, and normal gastric surface mucous epithelial cells, including rough endoplasmic reticulum, glycogen aggregates, Golgi apparatus, and mucous secretory granules, have common ultrastructural features associated with mucus synthesis. The morphologic heterogeneity of Barrett's specialized metaplastic cells and common ultrastructural features associated with normal mucus biosynthesis suggest that they develop from a gastrointestinal stem cell that retains the capacity for a wide range of normal and abnormal differentiation in the esophagus. The identity of this undifferentiated cell, which may reside in normal proximal gastric or esophageal mucosa, remains unknown. However, the gastric mucous neck cell has properties that suggest it could be the progenitor cell for Barrett's esophagus because it is a stem cell that has ultrastructural similarities to Barrett's specialized metaplastic epithelial cells and it is located in intact gastric mucosa adjacent to where Barrett's esophagus forms.
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PMID:Specialized metaplastic columnar epithelium in Barrett's esophagus. A comparative transmission electron microscopic study. 292 81

Diagnosis of the neoplastic progression in Barrett's esophagus using the histologic classification of dysplasia is frequently difficult. The tumor suppressor protein p53, when mutated, confers a promoter effect on cell growth. The purpose of this study was to evaluate the applicability of p53 as an intermediate biomarker of malignancy in Barrett's esophagus. Archival analysis of 100 biopsy specimens of Barrett's esophagus and 10 esophageal adenocarcinomas were compared with 35 chronic esophagitis biopsy specimens. Immunocytochemistry using an anti-p53 monoclonal antibody was performed and elevated immunoreactivity quantitated microscopically. Data were analyzed using a logistic regression model. Significant p53 immunoreactivity occurred as follows: chronic esophagitis (0%), Barrett's esophagus without dysplasia (10%), with low-grade dysplasia (60%), with high-grade dysplasia (100%), and adenocarcinoma (70%). All cases of Barrett's esophagus were significantly immunoreactive when compared with the chronic esophagitis cases (p = 0.001). There was an increase in p53 immunoreactivity as the histologic classification progressed toward adenocarcinoma (p = 0.001). Progression to high-grade dysplasia may be predicted based on p53 immunoreactivity. These findings suggest a role for p53 as an intermediate biomarker in Barrett's esophagus.
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PMID:Potential application of p53 as an intermediate biomarker in Barrett's esophagus. 814 27

Barrett's oesophagus is a change in the lining of the distal oesophagus recognised at endoscopy and documented to have intestinal metaplasia by biopsy. It is thought that it is an acquired condition resulting from chronic gastro-oesophageal reflux disease (GORD). Barrett's oesophagus has the potential to progress to adenocarcinoma of the oesophagus. Evidence to support the association between Barrett's oesophagus and GORD appears to be strong but circumstantial. The intermediate steps that lead from GORD to Barrett's oesophagus are speculative and the timeline for the development of this condition remains obscure. It has yet to be demonstrated that erosive oesophagitis is a necessary intermediate step for the development of Barrett's oesophagus. In spite of effective therapy, documentation that medical or surgical therapy prevents Barrett's oesophagus is lacking. The goal of screening for Barrett's oesophagus is ultimately to improve the survival of patients with adenocarcinoma of the oesophagus. This goal has not been achieved and the evidence-based criteria for screening remain to be defined. Medical and surgical therapy of Barrett's oesophagus is effective in controlling reflux, although not proven to prevent neoplastic progression of the at risk mucosa. Endoscopic techniques of mucosal injury have been applied as alternatives to oesophagectomy in efforts to prevent progression to cancer. Surveillance endoscopy and biopsy is the currently accepted method aimed at early intervention and improved survival for oesophageal adenocarcinoma. A working surveillance protocol to accomplish this is proposed based on dysplasia grade. If no dysplasia is found and confirmed with subsequent endoscopy and biopsy, a 3-year interval is recommended. If only low grade dysplasia is confirmed, then annual endoscopy until no dysplasia is recognised is recommended. On the basis of defined risk factors, high grade dysplasia can lead to intense surveillance every 3 months or an intervention. Future developments in understanding the biology of Barrett's oesophagus and in therapeutic interventions will provide an opportunity for more effective screening, surveillance and prevention of neoplastic progression.
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PMID:Barrett's oesophagus: optimal strategies for prevention and treatment. 1265 53

Recent research advances in cancer and molecular biology have furthered our understanding of the etiology and natural history of lung cancer. Through translational research, a growing understanding of the molecular changes that underlie cancer progression has contributed to the development of novel molecular approaches for early detection, further defining prognosis, refining treatment schedules, identifying new therapeutic targets, and identifying patients at risk for treatment-related toxicity from aggressive therapy, such as pneumonitis and esophagitis. In this article, we review progress in molecular/gene screening and prognosis, and we present a clinical study, based on preclinical research, in which we apply low-dose radiosensitizing paclitaxel for locally advanced non-small-cell lung cancer (NSCLC); this resulted in superior local tumor control while keeping treatment toxicity low. We also review progress made in identifying cytokines: interleukin [IL]-1alpha, IL-6, and transforming growth factor [TGF] beta as markers for lung cancer treatment-related radiation pneumonitis. Finally, we summarize different targeted therapy approaches and discuss their application to clinical trials. Irrespective of the slow progress toward clinical improvements, we have gained much knowledge through translational research using new molecular and biologic technology. We believe that knowledge of lung cancer biology will continue to provide the foundation for future improvements in lung cancer treatment.
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PMID:Translational research in lung cancer. 1450 54

GEM 231 is a second-generation antisense oligonucleotide targeted against the RIalpha regulatory subunit of cAMP-dependent protein kinase type I (PKA-I). Excessive expression of PKA-I is associated with cell proliferation and transformation, and increased levels of secreted extracellular PKA (ECPKA) are found in the serum of cancer patients. Preclinical studies have demonstrated single-agent antitumor activity of GEM 231 in a variety of human cancer xenograft models, and additive or synergistic antitumor activity has been observed with taxane and/or camptothecin-based combinations. Based on prior safety (MTD) data demonstrating dose-dependent, reversible, and cumulative transaminitis, and high peak plasma concentration (Cmax)-dependent changes in activated partial thromboplastin time (aPTT) with GEM 231 2-h twice-weekly infusions, an alternative schedule of GEM 231 given as a single agent was evaluated in patients with advanced solid tumors. Fourteen patients (median age approximately 60 yrs) with advanced solid malignancies received a total of 78 weeks of therapy. GEM 231 was infused via a CADD pump at 80 mg/m2/day (d) for 3 d/wk (n = 1), then for 5 d/wk at 80 (n = 3), 120 (n = 8), and 180 mg/m2/d (n = 2). One cycle was defined as 4 weeks of therapy. Apparent dose dependency for the occurrence of transaminitis was readily reversible. At 180 mg/m2/d, 2 of 2 patients had cycle 1 dose-limiting toxicity (DLT) transaminitis. One patient treated at 120 mg/m2/d experienced grade 3 transaminase elevations after 8 weeks of therapy, but when serum transaminase values rapidly improved he resumed treatment at 80 mg/m2/d for 6 weeks until tumor progression was documented. Another patient at 120 mg/m2/d developed grade 3 esophagitis after 3 weeks, limiting further dosing. One patient (lung cancer) demonstrated stable disease for 9 weeks. Overall, plasma aPTT was minimally prolonged and changes were transient, peaked at the end of each infusion, and were not associated with spontaneous bleeding. A constitutive symptom (e.g., low-grade fatigue) was common, cumulative, and reversible following discontinuation of therapy. Serum ECPKA was measured by enzymatic assay and Western blotting from blood drawn at the beginning and end of each infusion. Serum ECPKA levels demonstrated a trend to decline with the treatment. In addition to single agent schedules, combination trials were undertaken to assess safety and possible interaction of GEM 231 with taxanes (paclitaxel, docetaxel), given once every 3 weeks (one cycle). While trials using the 2-h twice-weekly GEM 231 infusions are ongoing, preliminary results from both studies show that it is safe to combine paclitaxel or docetaxel with GEM 231. Overall, it is also feasible to administer GEM 231 in combination with taxane or nontaxane chemotherapy (e.g., camptothecins). Phase I combination studies are currently underway to further explore the clinical, pharmacokinetic, and biologic profile of GEM 231 with chemotherapy.
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PMID:Clinical studies in patients with solid tumors using a second-generation antisense oligonucleotide (GEM 231) targeted against protein kinase A type I. 1475 40

SUMMARY. Esophageal cancer is one of the most deadly forms of gastrointestinal cancer with a mortality rate exceeding 90%. The major risk factors for esophageal adenocarcinoma are gastroesophageal reflux disease (GERD) and its sequela, Barrett's esophagus. GERD commonly leads to esophagitis. In a minority of patients however, ongoing GERD leads to replacement of esophageal squamous mucosa with metaplastic, intestinal-type Barrett's mucosa. In the setting of continued peptic injury, Barrett's mucosa can give rise to esophageal adenocarcinoma. Despite the widespread use of potent acid suppressive therapies for patients with GERD, the incidence of esophageal adenocarcinoma, among white men in the USA, the UK and Europe has continued to rise. Cancers in Barrett's esophagus arise through a sequence of genetic events that endow the cells with six essential physiologic hallmarks of cancer as described by Hanahan and Weinberg in 2000. These cancer hallmarks include the ability to proliferate without exogenous stimulation, to resist growth-inhibitory signals, to avoid triggering the programmed death mechanism (apoptosis), to resist cell senescence, to develop new vascular supplies (angiogenesis), and to invade and metastasize. While the acquisition of these essential attributes is not specific to the neoplastic progression of Barrett's esophagus, this review will focus on the genetic alterations that occur in Barrett's cells that contribute to the acquisition of each of the hallmarks. Moreover, potential diagnostic and therapeutic strategies for Barrett's patients aimed at each of these cancer hallmarks will be reviewed.
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PMID:Molecular targets for treatment of Barrett's esophagus. 1605 81

The purpose of the investigation was to study a role of tight junction (TJ) claudins (CL) in the morphogenesis of adenocarcinoma (AC) in the presence of Barrett's esophagus (BE). The investigation was performed on the specimens obtained from patients, including 41 males and 29 females, aged 16 to 81 years, with gastroesophageal reflux disease (GERD) at endoscopic biopsies and surgery. An immunohistological study was carried out using monoclonal antibodies to Cl 1, 2, 3, 4, 5, and 7 ("Zymed"). The location of a reaction product was defined in the epithelial membranes and cytoplasm (diffuse staining). The patients were divided into 6 groups: 1) GERD-esophagitis (a control group, n = 10); 2) GERD-esophagitis with gastric metaplasia (n = 15); 3) BE with enteric metaplasia (EM) without dysplasia (n = 9); 4) BE with colonic metaplasia (CM) without dysplasia (n = 9); 5) BE with varying dysplasia (the latter being detected in the presence of CM (n = 10); 6) AC in the presence of BE (n = 7). Transition of low- to high-grade dysplasia and to AC into BE was established to be accompanied by TJ loss, as appeared as disappearance of apical staining of Cl 1, 2, 3, 4, 5, and 7; moreover, their cytoplasmic staining increased in parallel. The lost capacity of accumulating Cl in the area of TJ in AC to BE led to the elimination of BE and promoted tumor progression (proliferation, invasion, and metastatic spread). The markers of cell differentiation of Cl 1, 2, 3, 4, 5, and 7 may be recommended for determination of the malignant potential of dysplasia to BE.
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PMID:[Role of tight junction claudins in the morphogenesis of adenocarcinoma in the presence of Barrett's esophagus]. 1913 78

Limited disease small cell lung cancer (LD-SCLC) is a heterogeneous disease, not only for its clinical behavior, but also for is anatomical extension. In very rare, early cases, LD-SCLC might be treated with surgery and chemotherapy, but as the overwhelming majority of patients present with locally advanced disease, the standard of care is concurrent chest radiotherapy with cisplatin and etoposide chemotherapy followed by prophylactic cranial irradiation (PCI). Newer chemotherapeutic drugs as well as targeted agents have not improved the outcome thus far. Given concurrently with chest irradiation, cisplatin combined with etoposide, administered every 21 days for 4-5 cycles have frequently been used. Thoracic radiotherapy should begin as early as possible during the first chemotherapy cycle. A total radiation dose of 45 Gy is recommended, delivered in a short overall treatment time (less than 4 weeks). Accelerated therapy increased absolute 5-year survival rates by 10% compared to longer treatment times, at the expense of an incidence of severe esophagitis of approximately 30%, which is reversible within a few weeks. Hematological complications and late pulmonary damage may occur, but is not more frequent than with less intensive schedules that impair long-term survival. Obviously, patient selection is crucial. Because after combined chemotherapy and thoracic radiotherapy, the remission status of the tumor is difficult to assess because of radiation-induced radiographic changes, patients that show no tumor progression are suitable for PCI. With this treatment, 5-year survival rates of 25% can be achieved in patients with LD-SCLC.
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PMID:Treatment of limited disease small cell lung cancer. 1995 4

Barrett's esophagus metaplasia is a pre-cancerous condition caused by chronic esophagitis. Chromosomal instability (CIN) is common in Barrett's cells: therefore, we investigated the possible presence of centrosomal aberrations (a main cause of CIN) by centrosomal protein immunostaining in paraffined esophageal samples of patients who developed a Barrett's adenocarcinoma. In most (55%) patients, alterations of the pericentriolar material (PCM) signals were evident and consistently marked the transition between normal epithelium to metaplasia. The alterations could even be found in adjacent native squamous epithelium, Barrett's mucosa and submucosal gland cells, as well as in the basal/epibasal layers of the mucosa and submucosal gland duct, which are the regions hosting esophageal stem and progenitor cells. These findings strongly support the hypothesis that the three esophageal histotypes (one being pathological) can have a common progenitor. Surprisingly, PCM defective signal eventually decreased with neoplastic progression, possibly to enhance the genome stability of advanced cancer cells. Importantly, PCM altered signals in Barrett's mucosa and their apparent evolution in successive histopathological steps were correlated to adenocarcinoma aggressiveness, suggesting PCM as a possible prognostic marker for tumor relapse. Extending our observations in a prospective study might help in the development of new prevention protocols for adenocarcinoma patients.
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PMID:Pericentriolar material analyses in normal esophageal mucosa, Barrett's metaplasia and adenocarcinoma. 2023 94

The normal squamous esophageal epithelium reacts as a chronic inflammation to the severe gastro-esophageal reflux. Esophagitis will progress to Barrett metaplasia in 10% of patients who would be of minor clinical interest if it then did not advance to low, high grade dysplasia and invasive carcinoma. The rise of esophageal adenocarcinoma (EAC) incidence surpasses any other cancer, including melanoma, lymphoma and small cell lung cancer. There is no clear proof that medical therapy could prevent the neoplastic progression. It seems that this population has a variable answer to proton pump inhibitors therapy. A multimodal approach of Barrett's esophagus with high grade dysplasia is required, including endoscopic mucosal resection, photodynamic therapy and thermal ablation. Photodynamic therapy could be used for the management of patients with high grade dysplasia, early EAC, local recurrence post radical therapy, microscopic involvement of tumor borders post radical resection, patient unfit / unwilling to undergo surgery. The palliation of non-resectable EAC by stenting represents the first choice. The correction of the malignant esophageal obstruction improves the symptomatology and life quality, but not survival. Because of the dismal prognosis and the frequent treatment failure of conventional treatment strategies, it seems reasonable to look for new palliative strategies.
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PMID:Endoscopic therapy of Barrett's esophagus and esophageal adenocarcinoma. 2059 60


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