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- Hedberg, Ylva, 1975-
(författare)
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Cell Cycle Regulation in Human Renal Cell Carcinoma
- 2003
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- ABSTRACTCell cycle regulation in human renal cell carcinomaYlva Hedberg, Departments of Medical Biosciences, Pathology, and Surgical andPerioperative Sciences, Urology Andrology, Umeå University, SwedenDeregulated growth control is a hallmark of neoplasia potentially caused by aberrant expression of cell cycle regulatory proteins. The importance of such aberrations in human renal cell carcinoma (RCC) has not been fully clarified. Therefore, the protein expressions of several G1/S regulatory proteins in human RCC were evaluated and their relation to clinico-pathological data was examined.Western blotting and immunohistochemistry were used to detect the proteinexpression of cyclin D1, D3, and E in 80 RCCs. Most tumors expressed higher levels of cyclin D1 (75%) and cyclin E (65%) compared to corresponding normal kidney cortex. In contrast, only 16 % of the tumors had high levels of cyclin D3. In conventional RCCs, low levels of cyclin D1 were associated with large tumor size, aneuploidy and a poor outcome for the patients. High expression of cyclin D3 and Ewere associated with aneuploidy, high proliferation, high TNM-stage, and high nuclear grade. Cyclin E was positively correlated to cyclin D3 but inversely associated with cyclin D1. Cyclin D3 and E were not associated with survival. The majority of RCCs had normal p27 levels, determined by immunohistochemistry, whereas the few tumors with low p27 levels were associated with large tumor size and poor survival.In order to confirm and extend our initial studies, a tissue microarray consisting of 218 RCCs was constructed and cyclin D1, D3, E, p27 were detected by immunohistochemistry. The tissue microarray results were validated by comparing the array data with western analyzes. Due to the large number of tumors analyzed we could evaluate potential differences in expression patterns of cell cycle regulators between conventional, papillary, and chromophobe RCCs. Interestingly, the protein expression differed between RCC types, showing that the conventional tumors generally had high cyclin D1 expression. In contrast, papillary and chromophobe RCCs had high cyclin E expression. Downregulation of p27 was found mostly in chromophobe RCCs. The retinoblastoma protein (pRb) was detected in all RCCs. Phosphorylation of pRb, detected by western blotting or immunohistochemistry and phospho-specific antibodies, was observed in approximately 50% of the tumors. The cdk-inhibitor p16 was not overexpressed suggesting that pRb was functional in the majority of RCCs.In summary, abnormal expression of G1-cyclins and the CDK-inhibitor p27 was common in RCC whereas the main G1/S-substrate, pRb, seemed to be functional. The aberrations further differed between the separate RCC subtypes and were linked to clinical behavior.
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| 2. |
- Adamo, Hanibal Hani, 1984-
(författare)
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TINT Tumor Indicating Normal Tissue : new field of diagnostic biomarkers for prostate cancer
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Prostate cancer is the most common cancer in Sweden. Due its highly variable behavior, multifocal nature, and insufficient diagnostic methods, prostate cancer is difficult to diagnose and prognosticate. Some patients have an aggressive lethal disease, but the majority of prostate cancer patients have slow-growing, non-lethal disease with long expected survival without treatment. Current diagnostic methods―serum levels of prostate-specific antigen (PSA) and histological grading of biopsied prostate tissue―often do not give the information required to be able to safely differentiate indolent tumors from potentially lethal ones. Many prostate cancers are difficult to detect by imaging, so tissue biopsy cannot be safely guided towards the tumor, and particularly not towards the most aggressive forms. To overcome this problem, multiple needle biopsies are taken from the organ, but biopsies are small and they sample less than 1% of the whole prostate. In this thesis, we explore the non-malignant prostate tissue adjacent to tumors, which is always sampled in biopsies, and we study adaptive changes in this tissue, which may provide new diagnostic and prognostic markers for prostate cancer. We have therefore proposed that this type of tissue should be termed TINT (Tumor Instructed/indicating Normal Tissue). Methods: In our studies, we used orthotopic rat prostate cancer models with tumors of different aggressiveness. We also used clinical materials from patients diagnosed with prostate cancer at transurethral resection (1975‒1990); the majority of these men were followed with watchful waiting. Analyses were performed with whole-genome expression array, quantitative real-time PCR, immunohistochemistry, and western blotting. Results: Using the animal model, we found that the presence of a tumor induces changes in gene expression in the surrounding tumor-bearing organ (TINT). The gene signature of TINT was linked to processes such as extracellular matrix organization, immune responses, and inflammation. We also showed that some of these adaptive TINT changes appear to be related to the aggressiveness and metastatic potential of the growing tumor, such as increases in macrophages, in mast cells, in vascular densities, and in vascular cell-proliferation. Some of these findings were confirmed by our observations in patient samples. We found that high staining of the extracellular matrix component hyaluronan in the stroma of the non-malignant prostate tissue was prognostic for short cancer-specific survival. We also found that an elevated proportion of C/EBP-beta positive epithelial cells in non-malignant (TINT) prostate tissue was associated with a good prognosis. Conclusions: Using animal experiments and patient samples, we showed that the presence of prostate cancer induces changes in the tumor-bearing organ, alterations associated with tumor aggressiveness, and that grading of these changes in TINT can be used to predict outcome in prostate cancer patients.
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| 3. |
- Ahlin, Cecilia, 1966-
(författare)
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Cyclin A and cyclin E as prognostic factors in early breast cancer
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Breast cancer is one of the most common malignancies in women. Due to early detection and the use of screening programs approximately 60% of all new cases lack lymph node involvement. Today, a substantial proportion of these women will be offered adjuvant systemic chemotherapy. However, better proliferation markers are needed to predict patient outcome and to avoid overtreatment. Cyclin A, cyclin E and Ki-67 are all markers for proliferation and involved in the regulation of the cell cycle. Overexpression has been associated with disease recurrence in several studies, but the results have not been consistent. However, none of these studies has investigated aberrant expression of cyclin E (the expression of cyclin E during phases of the cell cycle other than late G1 and early S-phase). Studies have shown that aberrant cyclin E might provide additional prognostic information compared to cyclin E alone.The aims of this thesis were 1.to investigate the prognostic value of cyclin A, cyclin E and aberrant cyclin E in early breast cancer. 2.to validate the tissue microarray (TMA) technique for cyclin A and 3.to define the most optimal cut-off values for cyclin A and Ki-67.We found that the agreement of TMA and large section results was good with kappa values 0.62-0.75 and that the reproducibility of the two readers’ results was good or even very good, with kappa values 0.71 – 0.87. The optimal cut-off value for cyclin A average was 8% and for cyclin A maximum value 11%. The corresponding values for Ki-67 were 15 and 22%. Neither cyclin E nor aberrant cyclin E was a prognostic factor in low-risk node negative breast cancer patients. Finally, we conclude that cyclin A is a prognostic factor in node negative breast cancer (univariate analysis average value OR=2.9 95% CI 1.8-4.6; maximum value OR=3.7 95% CI 2.3-5.9).
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| 4. |
- Ansell, Anna, 1983-
(författare)
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Identification of Tumor Cell- and Stroma Derived Biomarkers of Treatment Response in Head and Neck Cancer
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Head and neck squamous cell carcinoma (HNSCC) poses a major health problem in the world with approximately 600 000 new cases yearly. Treatment resistance is a major problem within this patient group and despite advances in treatment strategies the overall survival rate has unfortunately not increased.One of the major components of the tumor microenvironment is the cancer associated fibroblasts (CAFs) which can modulate the treatment sensitivity, tumor growth, and the invasive potential of tumor cells.The aim of this thesis was to identify predictive markers for treatment response in HNSCC and to study the crosstalk between tumor cells and CAFs that may underlie treatment resistance.In paper I, we identified gene expression differences between one cisplatin sensitive cell line and two cisplatin resistant cell lines, by microarray analysis, and found that a high expression of matrix metalloproteinase (MMP) -7 was associated with resistance to cisplatin. In paper II, the epidermal growth factor (EGF) receptor ligands EGF, amphiregulin, and epiregulin were evaluated regarding their potential use as predictive biomarkers for cetuximab treatment response in tongue cancer cell lines and it was shown that EGF may serve as a marker for poor cetuximab response. In paper III and IV, we investigated the influence of CAFs on the proliferation, migration, gene expression, and cetuximab response of tumor cells. It was found that CAFs induced resistance to cetuximab in a MMP-dependent manner. In addition, a microarray analysis, comparing tumor cells co-cultured with CAFs and tumor cells cultured alone, revealed that CAFs induced multiple gene expression changes in tumor cells some of which are related to epithelial to mesenchymal transition. Some of these changes were found to be dependent on cell-cell contact.Taken together, we here suggest MMP-7 and EGF to be predictive markers of cisplatin and cetuximab response, respectively. We also show that CAFs protect HNSCC cells from cetuximab treatment; however, the factor responsible for the protective effect is yet to be discovered.
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| 5. |
- Strömvall, Kerstin, 1980-
(författare)
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Extratumoral effects of highly aggressive prostate cancer
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Prostate cancer (PC) is the most common cancer in Sweden. Most patients have slow growing tumors that will not cause them any harm within their lifetime, but some have aggressive tumors and will die from their disease. The ability of current clinical practice to predict tumor behavior and disease outcome is limited leading to both over- and undertreatment of PC patients. The men who die from their disease are those that develop metastases. It is therefore of great value to find better and more sensitive prognostic techniques, so that metastatic spread can be detected (or predicted) at an early time point, and so that appropriate treatment can be offered to each subgroup of patients. The aim of this thesis was to investigate if, and by what means, highly aggressive prostate tumors influence extratumoral tissues such as the non-malignant parts of the prostate and regional lymph nodes (LN), and also if any of our findings could be of prognostic importance. Gene- and protein expression analysis were the main methods used to address these questions. Our research group has previously introduced the expression Tumor Instructed (Indicating) Normal Tissue (TINT), and we use the term TINT-changes when referring to alterations in non-malignant tissue due to the growth of a tumor nearby or elsewhere in the body. In the Dunning rat PC-model we found that MatLyLu (MLL)-tumors, having a high metastatic ability, caused pre-metastatic TINT-changes that differ from those caused by AT1-tumors who have low metastatic ability. Prostate-TINT surrounding MLL-tumors had elevated immune cell infiltration, and gene ontology enrichment analysis suggested that biological functions promoting tumor growth and metastasis were activated in MLL- while inhibited in AT1-prostate-TINT. In the regional LNs we found signs of impaired antigen presentation, and decreased quantity of T cells in the MLL-model. One of the downregulated genes in the MLL-LNs was Siglec1 (also known as Cd169), expressed by LN resident macrophages that are important for antigen presentation. When examining metastasis-free LN tissue from PC patients we found CD169 expression to be a prognostic factor for PC-specific survival, and reduced expression was linked to an increased risk of PC-specific death. Some of our findings in prostate- and LN-TINT could be seen already when the tumors were very small suggesting that differences in TINT-changes between tumors with different metastatic capability can be detected early in tumor progression. However, before coming of use in the clinic more research is needed to better define a suitable panel of prognostic TINT-factors as well as the right time window of when to use them.
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