| 1. |
- Farnebo, Lovisa, et al.
(författare)
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Number of negative points : a novel method for predicting radiosensitivity in head and neck tumor cell lines.
- 2008
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Ingår i: Oncology Reports. - : Spandidos Publications. - 1021-335X .- 1791-2431. ; 20:2, s. 453-461
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Tidskriftsartikel (refereegranskat)abstract
- The present study was aimed at establishing a method that combines multiple factors of protein and genetic changes that enables prediction of radiosensitivity in the head and neck squamous cell carcinoma (HNSCC) cell lines. In nine HNSCC cell lines, the quantity of protein expression and the type of genetic alterations were translated into a point system, called the Number of Negative Points. The expression of 14 proteins involved in growth control and/or apoptosis was quantified using a densitometric assessment of Western blots. The blots were adjusted to actin and standardised to normal oral keratinocytes classifying them into four groups depending on the amount of protein expressed (0-3 points). Mutations of the p53 gene were classified into three groups and each mutation was given one point. Since the cell lines each had a known intrinsic radiosensitivity, a multivariate statistical calculation could then be performed to select for the combination of factors having the strongest correlation to radiosensitivity. The strongest correlation of the investigated factors was the combination of epidermal growth factor receptor, survivin and splice site/missense p53 mutations (R=0.990 and P<0.0001). No single factor had a significant correlation to the intrinsic radiosensitivity. Since a significant correlation to the intrinsic radiosensitivity was achieved only when two or more factors were combined, we conclude that a method such as the Number of Negative Points is necessary for prediction of treatment response. We present a novel method to combine factors which enables the prediction of radiosensitivity of HNSCC cell lines.
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| 2. |
- Johansson, Ann-Charlotte, et al.
(författare)
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Role of lysosomal cathepsins in naphthazarin- and Fas-induced apoptosis in oral squamous cell carcinoma cells
- 2006
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Ingår i: Acta Oto-Laryngologica. - : Informa UK Limited. - 0001-6489 .- 1651-2251. ; 126:1, s. 70-81
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Tidskriftsartikel (refereegranskat)abstract
- Conclusion. Intracellular cysteine cathepsins are pro-apoptotic factors involved in activation of caspases in two oral squamous cell carcinoma (SCC) cell lines. Objective. To study the possible involvement of lysosomal cathepsins in oral SCC cell apoptosis. Material and methods. Apoptosis was induced in the two human oral SCC cell lines UT-SCC-20A and UT-SCC-24A using naphthazarin or anti-Fas antibodies, and was studied by analysis of caspase activity and nuclear morphology. Involvement of lysosomal cathepsins was investigated using the cysteine cathepsin inhibitor z-FA-FMK and the cathepsin D inhibitor pepstatin A. The amounts of cellular and soluble Fas death receptor were determined by ELISA. Results. Release of cathepsins from the lysosomes to the cytosol was observed early in apoptosis. Cysteine cathepsins were found to be involved in activation of caspases in response to treatment with naphthazarin or anti-Fas antibodies, but inhibition of cysteine cathepsin activity was not sufficient to prevent cell death. Moreover, inhibition of cysteine cathepsin activity resulted in increased expression of the Fas death receptor, suggesting involvement of extracellular cysteine cathepsins in death receptor shedding.
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| 3. |
- Roberg, Karin, 1957-, et al.
(författare)
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Multiple genotypic aberrances associate to terminal differentiation-deficiency of an oral squamous cell carcinoma in serum-free culture
- 2008
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Ingår i: Differentiation. - : Elsevier BV. - 0301-4681 .- 1432-0436. ; 76:8, s. 868-880
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Tidskriftsartikel (refereegranskat)abstract
- Oral squamous cell carcinoma (OSCC) lines proliferative in the serum-free conditions devised for normal oral keratinocytes (NOK) are virtually absent, complicating studies of carcinogenesis. A tongue squamous cell carcinoma generated under conditions for normal cell culture an apparently immortal line (termed LK0412) that has undergone ≥200 population doublings from over a year in culture. LK0412 exhibited epithelial morphology, intermediate filaments, desmosomes, and cytokeratin. Soft agar growth and tumorigenicity in athymic nude mice indicated the malignant phenotype. Compared with NOK, LK0412 exhibited increased indices for proliferation and apoptosis, and a decreased terminal differentiation index. Fetal bovine serum inhibited growth and increased apoptosis but failed to induce terminal differentiation of LK0412; the latter outcome differed clearly from that in NOK. Gene ontology assessment of transcript profiles implicated multiple alterations in biological processes, molecular functions, and cellular components in LK0412. Genetic changes, some that were confirmed to the protein level, included previously proposed OSCC markers, i.e., BAX, CDC2, and TP53, as well as multiple cancer-associated genes not considered for OSCC, e.g., BST2, CRIP1, ISG15, KLRC1, NEDD9, NNMT, and TWIST1. Elevation of p53 protein agreed with a missense mutation detectable in both the LK0412 line and the original tumor specimen. Moderate differentiation characterized the original tumor as well as tumors generated from inoculation of LK0412 in mice. Overall, the results suggest that the LK0412 cell line represent a subgroup of OSCC with unique genomic and phenotypic profiles. LK0412 should be useful to exploration of OSCC development, particularly the deregulated growth and differentiation responsiveness to serum factors.
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| 4. |
- Roberg, Karin, 1957-, et al.
(författare)
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Radiotherapy response in oral squamous carcinoma cell lines : Evaluation of apoptotic proteins as prognostic factors
- 2007
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Ingår i: Head and Neck. - : Wiley. - 1043-3074 .- 1097-0347. ; 29:4, s. 325-334
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Tidskriftsartikel (refereegranskat)abstract
- Background. In this study, we investigated the importance of apoptosis for cell death after radiotherapy, and whether the expression of pro- and anti-apoptotic proteins has any correlation to the radiosensitivity.Methods. Three oral squamous cell carcinoma cell lines, UT-SCC-2, UT-SCC-9 and UT-SCC-24A, were subjected to radiotherapy. After irradiation, viable and dead cells were counted to determine radiation sensitivity and apoptosis was analyzed by measurement of caspase-3 activity. The expressions of pro- and anti-apoptotic proteins were assessed using western blot analyses.Results and Conclusion. After irradiation, apoptotic morphology and caspase-3 activity were only detected in cell lines exhibiting high or moderate radiosensitivity. Western blot analysis indicates that survivin, epidermal growth factor receptor, cyclooxygenase-2, and Bcl-xL are critical components in irradiation resistance of the investigated cell lines. Moreover, our results suggest that apoptotic cell death and the balance between pro- and anti-apoptotic proteins are of importance for the outcome of radiotherapy.
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