Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Strong expression of aldehyde dehydrogenase is a prominent feature of both normal and cancer stem cells, including the stem cell sub-population of glioblastoma. Aldehyde dehydrogenase function is used by cancer stem cells to repopulate a tumor mass after chemotherapy cytoreduction. Cancer stem cells tend to be chemotherapy compared to the non-stem cell majority cell population in several common human cancers. Such has been demonstrated specifically in glioblastoma. In normal hematopoietic stem cells with unimpaired high levels of aldehyde dehydrogenase, stem cells divide rarely and then asymmetrically to a daughter stem cell and a daughter cell on a path of differentiation or symmetrically with both daughter cells on a differentiated path. If a parallel situation obtains in glioblastoma stem cells, the migrating, far flung paucicellular extensions will be stem cell rich and use aldehyde dehydrogenase to generate the characteristic multiple metastases made up of mostly non-stem cells. With inhibition of aldehyde dehydrogenase, stem cell division to non-stem daughter cells tends to become blocked. We have three old yet potent aldehyde dehydrogenase inhibitors on the market- chloral hydrate, chloramphenicol, and disulfiram- they should be investigated as adjuncts in glioblastoma chemotherapy. If GBM stem cell function can be thwarted by potent aldehyde dehydrogenase inhibition, they will be less able to regenerate a stem cell derived tumor mass after primary resection or chemotherapy.
 ...
PMID:Suppressing glioblastoma stem cell function by aldehyde dehydrogenase inhibition with chloramphenicol or disulfiram as a new treatment adjunct: an hypothesis. 1950 61

Cyclophosphamide remains one of the most successful and widely utilized antineoplastic drugs. Moreover, it is also a potent immunosuppressive agent and the most commonly used drug in blood and marrow transplantation (BMT). It was initially synthesized to selectively target cancer cells, although the hypothesized mechanism of tumor specificity (activation by cancer cell phosphamidases) transpired to be irrelevant to its activity. Nevertheless, cyclophosphamide's unique metabolism and inactivation by aldehyde dehydrogenase is responsible for its distinct cytotoxic properties. Differential cellular expression of aldehyde dehydrogenase has an effect on the anticancer therapeutic index and immunosuppressive properties of cyclophosphamide. This Review highlights the chemistry, pharmacology, clinical toxic effects and current clinical applications of cyclophosphamide in cancer and autoimmune disorders. We also discuss the development of high-dose cyclophosphamide for BMT and the treatment of autoimmune diseases.
 ...
PMID:Cyclophosphamide and cancer: golden anniversary. 1978 84

Patients with chronic ulcerative colitis are at increased risk of developing colorectal cancer. Although current hypotheses suggest that sporadic colorectal cancer is due to inability to control cancer stem cells, the cancer stem cell hypothesis has not yet been validated in colitis-associated cancer. Furthermore, the identification of the colitis to cancer transition is challenging. We recently showed that epithelial cells with the increased expression of aldehyde dehydrogenase in sporadic colon cancer correlate closely with tumor-initiating ability. We sought to determine whether ALDH can be used as a marker to isolate tumor-initiating populations from patients with chronic ulcerative colitis. We used fluorescence-activated cell sorting to identify precursor colon cancer stem cells from colitis patients and report both their transition to cancerous stem cells in xenografting studies as well as their ability to generate spheres in vitro. Similar to sporadic colon cancer, these colitis-derived tumors were capable of propagation as sphere cultures. However, unlike the origins of sporadic colon cancer, the primary colitic tissues did not express any histologic evidence of dysplasia. To elucidate a potential mechanism for our findings, we compared the stroma of these different environments and determined that at least one paracrine factor is up-regulated in the inflammatory and malignant stroma compared with resting, normal stroma. These data link colitis and cancer identifying potential tumor-initiating cells from colitic patients, suggesting that sphere and/or xenograft formation will be useful to survey colitic patients at risk of developing cancer.
 ...
PMID:Aldehyde dehydrogenase-expressing colon stem cells contribute to tumorigenesis in the transition from colitis to cancer. 1980 66

Hepatocellular carcinoma (HCC) is associated with a high morbidity and mortality due to its high rate of recurrence. However, little is known about the biological characteristics of recurrent HCC cells. A single patient's primary and recurrent HCC-derived cell lines, Hep-11 and Hep-12, respectively, were established by primary culture. These two cell lines have the same hepatitis B virus integration site and share many common amplifications and deletions, which suggest that they have the same clonal origin. While Hep-11 cells were non-tumorigenic at 16 weeks following injection of up to 10 000 cells, injection of only 100 Hep-12 cells was sufficient to initiate tumor growth, and all single Hep-12 clones were tumorigenic in immunodeficient mice. Compared with Hep-11, Hep-12 cells expressed the oval cell markers AFP, NCAM/CD56, c-kit/CD117, as well as multiple stem cell markers such as Nanog, OCT4 and SOX2. In addition, >90% of Hep-12 cells were aldehyde dehydrogenase positive. They were also less resistant to paclitaxel, but more resistant to doxorubicin, cisplatin and hydroxycamptothecin (HCPT), which had been administrated to the patient. Furthermore, Hep-12 cells expressed higher levels of poly (adenosine diphosphate-ribose) polymerase-1 (PARP-1) than Hep-11, and PARP-1 inhibition potentiated the sensitivity to HCPT in Hep-12 cells but not in Hep-11 cells. These results indicate that a large population of the recurrent HCC-derived Hep-12 cells were tumor-initiating cells and that elevated expression of PARP-1 was related to their resistance to HCPT.
 ...
PMID:The properties of tumor-initiating cells from a hepatocellular carcinoma patient's primary and recurrent tumor. 1989 2

Tumor stem cells or cancer initiating cells (CICs) are single tumor cells that can regenerate a tumor or a metastasis. The identification and isolation of CICs remain challenging, and a variety of putative CIC markers have been described. We hypothesized that cell lines of the NCI60 panel contain CICs and express putative CIC markers. We investigated expression of putative CIC surface markers (CD15, CD24, CD44, CD133, CD166, CD326, PgP) and the activity of aldehyde dehydrogenase in the NCI60 panel singly and in combination by six-color fluorescence-activated cell sorting analysis. All investigated markers were expressed in cell lines of the NCI60 panel. Expression levels of individual markers varied widely across the 60 cell lines, and neither single marker expression nor simple combinations nor co-expression patterns correlated with the colony-formation capacity of cell lines. Rather, marker expression patterns correlated with tumor types in multidimensional analysis. Whereas some expression patterns correlated with tumor entities such as basal breast cancer, other expression patterns occurred across different tumor types and largely related to expression of a more mesenchymal phenotype in individual breast, lung, renal, and melanoma cell lines. Our data for the first time demonstrate that tumor cell lines display CIC markers in a complex pattern that relates to the tumor type. The complexity and tumor type specificity of marker display creates challenges for the application of cell sorting and other approaches to isolation of putative tumor stem cell populations and suggests that therapeutic targeting strategies will need to take this into account.
 ...
PMID:Complex display of putative tumor stem cell markers in the NCI60 tumor cell line panel. 2017 9

To investigate the tumor fraction with cancer stem/tumor initiating cell (CSC/TIC) characteristics, we tested the human cervical carcinoma cell lines A431, Caski and SiHa, by growth as non-adherent spheres in specific media and aldehyde dehydrogenase (ALDH) enzymatic activity. A good correlation between the two parameters was observed and the highest levels were observed in A431 cell line that was selected for characterization of the CSC/TIC fraction. A431 parental cells already displayed characteristics common to CSC/TIC, such as sphere forming efficiency, adherent holoclone formation and high ALDH activity. Non-adherent spheres maintained or increased these properties, and, in particular, ALDH-positive fraction increased from 46 to 65% and a transient induction of stem cell markers such as Nanog, Nestin and Oct4 was observed. Furthermore, a significant increase of paraclone forming cells was observed, suggesting that differentiation took place inside sphere cell populations. As compared to parental cells, spheres were characterized by: (1) a ten-fold higher verapamil-sensitive side population fraction; (2) the appearance of a podoplanin-positive subpopulation characterized by a small cell size; (3) the ability to propagate tumors in nude mice at a lower cell dose. The global gene expression analysis demonstrated a strong and reversible modulation of 'sphere' phenotype in comparison to parental and sphere cells re-induced to adherent conditions. All together our results indicated that the growth of A431 cells as a non-adherent sphere was not sufficient by itself to define a stem-like population, but it was essential for the emergence of a small population of tumor cells with CSC properties.
 ...
PMID:Tumor initiating cells: development and critical characterization of a model derived from the A431 carcinoma cell line forming spheres in suspension. 2023 14

High aldehyde dehydrogenase (ALDH) activity has recently been used to identify tumorigenic cell fractions in many cancer types. Herein we hypothesized that a subpopulation of cells with cancer stem cells (CSCs) properties could be identified in established human osteosarcoma cell lines based on high ALDH activity. We previously showed that a subpopulation of cells with high ALDH activity were present in 4 selected human osteosarcoma cell lines, of which a significantly higher ALDH activity was present in the OS99-1 cell line that was originally derived from a highly aggressive primary human osteosarcoma. Using a xenograft model in which OS99-1 cells were grown in NOD/SCID mice, we identified a highly tumorigenic subpopulation of osteosarcoma cells based on their high ALDH activity. Cells with high ALDH activity (ALDH(br) cells) from the OS99-1 xenografts were much less frequent, averaging 3% of the entire tumor population, compared to those isolated directly from the OS99-1 cell line. ALDH(br) cells from the xenograft were enriched with greater tumorigenicity compared to their counterparts with low ALDH activity (ALDH(lo) cells), generating new tumors with as few as 100 cells in vivo. The highly tumorigenic ALDH(br) cells illustrated the stem cell characteristics of self-renewal, the ability to produce differentiated progeny and increased expression of stem cell marker genes OCT3/4A, Nanog and Sox-2. The isolation of osteosarcoma CSCs by their high ALDH activity may provide new insight into the study of osteosarcoma-initiating cells and may potentially have therapeutic implications for human osteosarcoma.
 ...
PMID:Prospective identification of tumorigenic osteosarcoma cancer stem cells in OS99-1 cells based on high aldehyde dehydrogenase activity. 2030 79

The cancer stem cell (CSC) theory has been proposed to explain the tumor heterogeneity and carcinogenesis process. Recent studies indicate that aldehyde dehydrogenase (ALDH) activity represents a promising CSC marker. Here, we aimed to determine whether human adenoid cystic carcinoma (AdCC) also follows CSC model by exploring the CSC properties of AdCC cells expressing high level of ALDH activity. Utilizing in-vivo series transplantation assays, we found ALDH(high) AdCC cells were capable of self-renewal and of generating tumors that recapitulate the heterogeneity of the parental tumor. Utilizing in-vitro assay, we found only ALDH(high) AdCC cells have tumorsphere-forming ability in anchorage-independent cultures. Finally, we showed ALDH(high) AdCC cells possess highly invasive capability and are responsible for mediating metastasis. These findings suggest the existence of a developmental hierarchy within human AdCC and further elucidation of the unique survival mechanism of AdCC derived CSC population may provide novel therapeutic strategies to treat AdCC.
 ...
PMID:ALDH high adenoid cystic carcinoma cells display cancer stem cell properties and are responsible for mediating metastasis. 2045 Aug 87

Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) are present in gastric cancer cells (GC). Moreover, the activity of total ADH and class IV isoenzymes is significantly higher in cancer tissue than in healthy mucosa. The activity of these enzymes in cancer cells is probably reflected in the sera and could thus be helpful for diagnostics of gastric cancer. The aim of this study was to investigate a potential role of ADH and ALDH as tumor markers for gastric cancer. We defined diagnostic sensitivity, specificity, predictive value for positive and negative results, and receiver-operating characteristics (ROC) curve for tested enzymes. Serum samples were taken from 168 patients with gastric cancer before treatment and from 168 control subjects. Total ADH activity and class III and IV isoenzymes were measured by photometric but ALDH activity and ADH I and II by the fluorometric method, with class-specific fluorogenic substrates. There was significant increase in the activity of ADH IV isoenzyme and ADH total in the sera of gastric cancer patients compared to the control. The diagnostic sensitivity for ADH IV was 73%, specificity 79%, positive and negative predictive values were 81 and 72% respectively. Area under ROC curve for ADH IV was 0.67. The results suggest a potential role for ADH IV as marker of gastric cancer.
 ...
PMID:The diagnostic value of alcohol dehydrogenase (ADH) isoenzymes and aldehyde dehydrogenase (ALDH) measurement in the sera of gastric cancer patients. 2045 95

Metastatic progression of advanced prostate cancer is a major clinical problem. Identifying the cell(s) of origin in prostate cancer and its distant metastases may permit the development of more effective treatment and preventive therapies. In this study, aldehyde dehydrogenase (ALDH) activity was used as a basis to isolate and compare subpopulations of primary human prostate cancer cells and cell lines. ALDH-high prostate cancer cells displayed strongly elevated clonogenicity and migratory behavior in vitro. More strikingly, ALDH-high cells readily formed distant metastases with strongly enhanced tumor progression at both orthotopic and metastatic sites in preclinical models. Several ALDH isoforms were expressed in human prostate cancer cells and clinical specimens of primary prostate tumors with matched bone metastases. Our findings suggest that ALDH-based viable cell sorting can be used to identify and characterize tumor-initiating and, more importantly perhaps, metastasis-initiating cells in human prostate cancer.
 ...
PMID:High aldehyde dehydrogenase activity identifies tumor-initiating and metastasis-initiating cells in human prostate cancer. 2051 16


<< Previous 1 2 3 4 5 6 7 8 9 10