Publications by authors named "Jansina Y Fok"

Many studies have supported a role for inflammation in prostate tumour growth. However, the contribution of inflammation to the development of castration-resistant prostate cancer remains largely unknown. Based on observations that aberrant expression of the proinflammatory protein tissue transglutaminase (TG2) is associated with development of drug resistance and metastatic phenotype in multiple cancer types, we determined TG2 expression in prostate cancer cells.

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Preclinical data suggest that combined EGF receptor (EGFR) targeting with an EGFR tyrosine kinase inhibitor and an anti-EGFR monoclonal antibody may be superior over single-agent targeting. Therefore, as part of a phase I study, we analyzed the outcome of 20 patients with non-small cell lung cancer treated with the combination of erlotinib and cetuximab. EGFR mutation status was ascertained in a Clinical Laboratory Improvement Amendment-approved laboratory.

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Purpose: Single-agent EGFR inhibitor therapy is effective mainly in patients with lung cancer and EGFR mutations. Treating patients who develop resistance, or who are insensitive from the outset, often because of resistant mutations, other aberrations or the lack of an EGFR mutation, probably requires rational combinations. We therefore investigated the outcome of EGFR inhibitor-based combination regimens in patients with heavily-pretreated non-small cell lung cancer (NSCLC) referred to a Phase I Clinic.

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Tissue type transglutaminase (TG2) is a unique multifunctional protein that plays a role in many steps in the cancer metastatic cascade. Here, we examined the clinical (n = 93 epithelial ovarian cancers) and biological (in vitro adhesion, invasion, and survival and in vivo therapeutic targeting) significance of TG2 in ovarian cancer. The overexpression of TG2 was associated with significantly worse overall patient survival in both univariate and multivariate analyses.

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Purpose: Pancreatic ductal adenocarcinoma (PDAC) progresses rapidly and exhibits profound resistance to treatment. We recently reported that a great majority of PDAC tumors and tumor cell lines express elevated levels of tissue transglutaminase (TG2). Here, we provide first evidence that TG2 expression in PDAC cells results in constitutive activation of focal adhesion kinase/AKT by modulating the expression of the tumor suppressor phosphatase PTEN.

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Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignant disease with poor long-term survival rates. Major reason for poor disease outcome is the profound intrinsic resistance of PDAC cells to currently available treatment regimens. We recently found that a great majority of PDAC tumors and tumor cell lines express high basal level of tissue transglutaminase (TG2), a multifunctional protein implicated in apoptosis, cell attachment, cell survival, and cell motility functions.

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Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive neoplastic diseases and is virtually incurable. The molecular mechanisms that contribute to the intrinsic resistance of PDAC to various anticancer therapies are not well understood. Recently, we have observed that several drug-resistant and metastatic tumors and tumor cell lines expressed elevated levels of tissue transglutaminase (TG2).

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The transcription factor nuclear factor-kappaB (NF-kappaB) plays an important role in regulating cell growth, apoptosis, and metastatic functions. Constitutive activation of NF-kappaB has been observed in various cancers; however, molecular mechanisms resulting in such activation remain elusive. Based on our previous results showing that drug-resistant and metastatic cancer cells have high levels of tissue transglutaminase (TG2) expression and that this expression can confer chemoresistance to certain types of cancer cells, we hypothesized that TG2 contributes to constitutive activation of NF-kappaB.

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Human malignant melanoma is a highly aggressive form of cancer; the 5-year survival rate in patients with stage III or IV disease is <5%. In patients with metastatic melanoma, systemic therapy becomes ineffective because of the high resistance of melanoma cells to various anticancer therapies. We have found previously that development of the drug resistance and metastatic phenotypes in breast cancer cells is associated with increased tissue transglutaminase (TG2) expression.

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