Developing Sustainable Cancer Education Programs: Training Public Health Students to Deliver Cancer 101 in Puerto Rico.

The use of promotores to educate Hispanic communities about different health topics has been proven successful, albeit with limitations in program sustainability. The goal of this study was to develop a sustainable train-the-trainer model to train graduate public health (PH) students to disseminate cancer education among communities in Puerto Rico (PR). Graduate students (n = 32) from Ponce Health Sciences University's (PHSU) PH program participated in a 2-day Cáncer 101 training, where they learned how to deliver nine cancer modules to the community. Cancer knowledge was assessed before and after the training via 54 items measuring discussed concepts. Participants also assessed the training's effectiveness by completing a training evaluation informed by social cognitive theory (SCT) constructs of self-efficacy, outcome expectations, facilitation, and observational learning. Participants were mainly female (78.1 %), 26.7 ± 3.9 years old, and enrolled in a Masters-level program (81.3 %). Participants reported an average 11.38-point increase in cancer knowledge after attending the training [t(31) = 14.88, p < .001]. Participants also evaluated the training favorably upon completion, reporting satisfactory comments in the open-ended responses and high scores on measured SCT constructs. The Cáncer 101 training program effectively prepared students to deliver cancer education to local communities. Training graduate PH students to educate communities about health issues is an innovative, and potentially sustainable, way to reach underserved populations.

When a Common Language Is Not Enough: Transcreating Cancer 101 for Communities in Puerto Rico.

In Puerto Rico (PR), cancer is the leading cause of death. Previous research has identified the need for cancer education in PR. Using culturally adapted cancer curricula to train local health educators may effectively increase cancer education and reduce health disparities. This article describes the three-phase process used to transcreate the Cancer 101 curriculum to train Master of Public Health (MPH) students to educate PR communities. First, an expert panel collaboratively reviewed the curriculum for content, legibility, utility, and colloquialisms. Recommendations included incorporating local references and resources, replacing words and examples with culturally relevant topics, and updating objectives and evaluation items. Subsequent focus groups with 10 MPH students assessed the adaptation's strengths, weaknesses, and utility for future trainees. Participants were satisfied with the curriculum's overall adaptation, ease of use, and listed resources; further improvements were suggested for all modules. Final expert panel revisions highlighted minor feedback, with the final curriculum containing nine transcreated modules. The transcreation process identified the need for changes to content and cultural translation. Changes were culturally and literacy-level appropriate, represented PR's social context, and were tailored for future trainees to successfully deliver cancer education. Findings highlight the importance of adapting Spanish educational materials across Hispanic sub-groups.

Regulation of the human transforming growth factor beta type II receptor gene promoter by novel Sp1 sites.

The transforming growth factor-beta (TGF beta) type II receptor (T beta R-II) is responsible for transducing the growth inhibitory signals of TGF beta. The T beta R-II gene promoter lacks both a TATA box and a CAAT box near the transcription initiation site, and has been shown to contain binding sequences for several transcription factors (Sp1, AP1, NF-Y, Cut and ERT) which are important for T beta R-II gene promoter activity in vitro. However, it is still not clear which interactions are important for the regulation of T beta R-II gene promoter activity in vivo. Using in vivo genomic DNA footprinting of normal human epithelial cells (HaCaT), we have identified two novel identical and strongly protected sites (ggggctgg) at positions -59 and -102 of the T beta R-II gene promoter. Mutation of either site significantly reduced promoter activity in transient transfections. Protein binding to these sites, as determined by electrophoretic mobility shift assays (EMSA), was specifically competed with consensus Sp1 oligonucleotides. Furthermore, anti-Sp1/3 antibodies produced band shifts when incubated with the T beta R-II -59 and -102 DNA probes. Importantly, Sp1 protein binding was influenced by the presence of an intact NF-Y binding site at position -83. Our data suggests that both Sp1 and NF-Y may play an important role in regulating T beta R-II gene promoter basal activity in vivo.

Identification of genetic alterations in the TGFbeta type II receptor gene promoter.

Modifications in the control sequences of tumor suppressor genes have been found to play a role in the activation or inactivation of these genes and may play an important role in tumorigenesis. For example, hypermethylation of CpG islands and promoter polymorphisms have been found to be involved in transcriptional repression. A decrease in the levels of expression of one such tumor suppressor gene, the TGFbeta type II receptor (TbetaR-II), has been associated with increased tumorigenicity in a number of human tumors. Genetic alterations have been described in several tumor types in the coding region of this gene. However, no comprehensive search for genetic alterations in the TbetaR-II promoter has been reported. Genetic alterations in the promoter of the TbetaR-II gene could inhibit binding of putative regulatory factors. For example, we have reported a A-364-G alteration in the TbetaR-II promoter, which results in decreased transcriptional activity. In this study, we analyzed the 1.0kb region upstream of the TbetaR-II transcriptional start site and found genetic alterations in 46% of the head and neck squamous cell carcinoma (SqCC) samples examined. The most frequent alteration was a G-875-A alteration, present in 41.6% of the samples. Analysis of normal healthy individuals showed a similar frequency of this alteration, suggesting that alterations within the TbetaR-II promoter are unlikely to account for the decreased expression of TbetaR-II in head and neck SqCC.

Defective transforming growth factor beta signaling pathway in head and neck squamous cell carcinoma as evidenced by the lack of expression of activated Smad2.

PURPOSE: Transforming growth factor beta (TGF-beta) regulates cell growth and differentiation, in normal squamous epithelium, via specific TGF-beta receptors and intracellular signaling molecules (Smads). We have previously observed that TGF-beta type II receptor (TbetaR-II) expression decreases in squamous cell carcinomas as tumors become less differentiated and more biologically aggressive. However, a small fraction of tumors remain TbetaR-II positive. In this article, we examine the integrity of the other members of the TGF-beta-signaling machinery, the Smad proteins. EXPERIMENTAL DESIGN: Thirteen archived head and neck squamous cell carcinomas were selected from the files of the Pathology Department of the H. Lee Moffitt Cancer Center. Protein immunoexpression was quantitated by image analysis in the context of histopathological parameters. Mutation analysis of the MADR2/Smad2 gene was also performed. RESULTS: In both TbetaR-II-positive and TbetaR-II-negative tumors, expression of the non-TGF-beta-specific Smads (4, 6, and 7) was variable, whereas expression of the pathway-specific Smad2 was lost in 38% of the tumors. Expression of the activated, phosphorylated form of this molecule, Smad2-P, was lost in approximately 70% of the tumors. No abnormal mRNA expression and no mutations in the MADR2/Smad2 gene were observed. CONCLUSIONS: These results suggest that multiple defects in TGF-beta signaling, both at the receptor and postreceptor level, may play a role in the oncogenesis of head and neck squamous cell carcinoma.

Inhibition of farnesyltransferase increases TGFbeta type II receptor expression and enhances the responsiveness of human cancer cells to TGFbeta.

Several small GTPases of the Ras superfamily have been shown to antagonize TGFbeta signaling in human tumor cell lines. Some of these GTPases are post-translationally modified by farnesylation, a lipid modification catalyzed by farnesyltransferase and required for the proteins to attach to membranes and to function. In this study, we investigated the effect of the farnesyltransferase inhibitor FTI-277 on TGFbeta-regulated cell growth and transcription. Treatment of the human pancreatic tumor cell line, Panc-1, with FTI-277 enhanced the ability of TGFbeta to inhibit both anchorage-dependent and -independent tumor cell growth. FTI-277 also enhanced the ability of TGFbeta to induce transcription, as measured by p3TP-lux reporter activity and collagen synthesis. The enhancement of TGFbeta responses by FTI-277 correlated with the stimulation of transcription and protein expression of type II TGFbeta receptor (TbetaRII). Consequently, FTI-277-treated cells exhibited a higher level of TGFbeta binding to its receptor. Thus, inhibition of protein farnesylation stimulates TbetaRII expression, which leads to increased TGFbeta receptor binding and signaling as well as inhibition of tumor cell growth and transformation.

Radiation effects on osteoblasts in vitro: a potential role in osteoradionecrosis.

OBJECTIVE: To evaluate the factors involved in bone remodeling and wound healing that may be altered by radiation therapy. DESIGN: A prospective, controlled study of biochemical activity in vitro. SUBJECTS: MC3T3-E1 mouse osteoblasts. INTERVENTIONS: Cells were irradiated at 0, 2, 4, or 6 Gy. Specimens were harvested at 1, 7, 14, 28, and 42 days following irradiation for immunohistochemical analysis of transforming growth factor beta(1) expression and transforming growth factor beta(1) type I and II receptor expression. Collagen production was measured at 1, 7, 28, 35, and 49 days after irradiation. The effects of dexamethasone on collagen production and cell proliferation were also examined. RESULTS: Irradiated cells demonstrated decreased cell proliferation and a dose-dependent, sustained reduction in collagen production when compared with control cells. An increase in transforming growth factor beta(1) type I and II receptor expression was noted in irradiated cells when compared with controls. CONCLUSION: Radiation-induced alterations of factors related to bone remodeling and wound healing have a potential role in the pathogenesis of osteoradionecrosis.

Transforming growth factor-beta type II receptors and smad proteins in follicular thyroid tumors.

OBJECTIVE: Resistance to transforming growth factor (TGF)-beta-mediated cell growth inhibition is a well-known pathogenic mechanism in epithelial neoplasia. TGF-beta signaling requires normal function of downstream mediators such as TGF-beta receptors (TbetaRs) and Smad proteins. The goal of this study is to investigate the expression of components of the TGF-beta signaling pathway in follicular tumors of the thyroid. STUDY DESIGN: Twenty follicular thyroid neoplasms were classified as adenomas (11) or minimally invasive follicular carcinomas (9) according to current pathological criteria. Protein expression was evaluated to identify differences between benign and malignant tumors that could be used as an adjunct to histopathological analysis. METHODS: Paraffin-embedded tissue sections containing tumor and adjacent nonneoplastic parenchyma were analyzed by immunohistochemistry for the expression of TbetaR type II (TbetaR-II) and Smad2, Smad4, Smad6, and Smad7. Expression of each protein in the tumor was compared with that of the corresponding adjacent nonneoplastic thyroid parenchyma. RESULTS: TbetaR-II expression was lost in 78% of the carcinomas. In the remaining 22%, TbetaR-II was preserved but Smad2 expression was lost. In all conventional adenomas, however, TbetaR-II expression was maintained. Furthermore, all tumors with normal expression of all proteins were adenomas. CONCLUSIONS: Downregulation of TbetaR-II is a consistent abnormality in follicular carcinomas and can be used to differentiate minimally invasive carcinomas from adenomas. Also, downregulation of Smad proteins is another mechanism by which carcinomas can become independent from TGF-beta-mediated growth inhibition.

Requirement of SHP2 binding to Grb2-associated binder-1 for mitogen-activated protein kinase activation in response to lysophosphatidic acid and epidermal growth factor.

Grb2-associated binder-1 (Gab1) is a multisite docking protein containing a pleckstrin homology (PH) domain, multiple potential tyrosine phosphorylation sites, and several proline-rich sequences. Gab1 becomes tyrosine-phosphorylated in cells stimulated with growth factors, cytokines, and ligands for G protein-coupled receptors. A major Gab1-binding protein detected in cells treated with extracellular stimuli is the tyrosine phosphatase, SHP2. Although the role of SHP2-Gab1 interaction in cell signaling has not yet been characterized, SHP2 is known to mediate mitogen-activated protein (MAP) kinase activation induced by the epidermal growth factor (EGF). However, the mechanism by which the SHP2 phosphatase exerts a positive signaling role remains obscure. In this study, we prepared Gab1 mutants lacking the SHP2 binding site (Gab1Y627F), the phosphatidylinositol 3-kinase (PI3K) binding sites (Gab1DeltaPI3K), and the PH domain (Gab1DeltaPH). Expression of Gab1Y627F blocked the extracellular signal-regulated kinase-2 (ERK2) activation by lysophosphatidic acid (LPA) and EGF. Conversely, expression of the wild-type Gab1 in HEK293 cells augmented the LPA receptor Edg2-mediated ERK2 activation. Whereas the PH domain was required for Gab1 mediation of ERK2 activation by LPA, it was not essential for EGF-induced ERK2 activation. Expression of Gab1DeltaPI3K had no apparent effect on ERK2 activation by LPA and EGF in the cells that we have examined. These results establish a role for Gab1 in the LPA-induced MAP kinase pathway and clearly demonstrate that Gab1-SHP2 interaction is essential for ERK2 activation by LPA and EGF. These findings also suggest that the positive role of SHP2 in the MAP kinase pathway depends on its interaction with Gab1.

Human cut-like repressor protein binds TGFbeta type II receptor gene promoter.

Resistance to the growth inhibitory effects of transforming growth factor beta (TGFbeta) has been associated with decreased levels of the TGFbeta type II receptor (TbetaR-II) and has been correlated with tumorigenicity. Previously, we reported an A --> G mutation at position -364 in the TbetaR-II promoter in A431 tumor cells which results in reduced TbetaR-II promoter activity. In this study, we show that the CDP/Cut (CCAAT displacement protein) transcription factor, a transcriptional repressor, binds both the wild type and the mutant TbetaR-II promoter. We also demonstrate that the A --> G mutation increases CDP/Cut binding affinity, and that overexpression of CDP/Cut reduces transcription from TbetaR-II promoter reporter constructs. Increased binding of the CDP/Cut repressor protein, as a result of a mutation at position -364, represents a novel mechanism of regulation in a neoplastic cell of the promoter of a tumor suppressor gene, TbetaR-II.

Transforming growth factor beta receptors in verrucous and squamous cell carcinoma.

OBJECTIVES: To study the intracellular location of transforming growth factor beta type II receptors (TbetaR-II) in verrucous carcinoma (VC) and squamous cell carcinoma (SqCC), and to evaluate their role in the biological behavior of both neoplasias. DESIGN: Ten VC and 10 well-differentiated SqCC specimens were analyzed by immunohistochemistry and in situ hybridization for the expression and intracellular location of TbetaR-II. Receptor expression was evaluated in areas of invasion and in areas of transformation of VC into SqCC. TbetaR-II expression was compared with expression of the type I receptor (TbetaR-I). SUBJECTS: Formalin-fixed, paraffin-embedded tissue sections from VCs and well-differentiated SqCCs, operated on at the H. L. Moffitt Cancer Center and Research Institute from May 1987 to January 1998, were selected for the study. INTERVENTIONS: None. RESULTS: While in all VCs TbetaR-II was found to be located along the membrane of the neoplastic keratinocytes, TbetaR-II expression in SqCC was observed predominantly in a cytoplasmic location. This cytoplasmic location of TbetaR-II was also seen in areas of transition from VC to SqCC. Expression of TbetaR-I was found in a cytoplasmic location in both tumor types. CONCLUSIONS: The membranous location of TbetaR-II in VC exposes the receptor to the growth inhibitory control of TGF-beta and may explain why VC tumors are less aggressive clinically. The marked reduction of membranous TbetaR-II and their predominant cytoplasmic location diminishes TGF-beta growth inhibition and may contribute to the transformation of VC into the more aggressive SqCC.

Expression of transforming growth factor beta type II receptors in head and neck squamous cell carcinoma.

Transforming growth factor (TGF)-beta is a potent regulator of growth and differentiation in normal squamous epithelium. TGF-beta exerts its antiproliferative effect via the TGF-beta type II receptor (TbetaR-II). A decrease in TbetaR-II expression is believed to be responsible, in part, for the resistance of squamous cell carcinoma (SqCC) to the anti-proliferative effects of TGF-beta. In the present study, we used immunohistochemistry and in situ hybridization to analyze the expression of TbetaR-II along the successive oncogenic stages of head and neck squamous neoplasia, from normal epithelium to dysplasia to carcinoma. Quantitation of TbetaR-II expression in 38 SqCCs was assessed on a visual scale ranging from negative (absence of staining) to 3+ (strong staining). Normal squamous epithelium and squamous epithelium in the vicinity of the tumors showed homogenous receptor expression with moderate intensity. Dysplastic epithelium and carcinoma in situ showed a mild decrease in receptor expression intensity. Well-differentiated to moderately differentiated carcinomas showed heterogeneous expression of variable intensity, and poorly differentiated carcinomas were completely devoid of TbetaR-II. In every tumor, the superficial component showed more intense receptor expression than the invasive component. These results indicate that TbetaR-II expression inversely correlates with disease aggressiveness and suggest that aberrant TbetaR-II expression is a contributing factor to the pathogenesis of SqCC.

Transforming growth factor beta receptors and p27kip in thyroid carcinoma.

OBJECTIVE: To investigate the role of cell cycle regulators in the pathogenesis of papillary carcinoma of the thyroid. DESIGN: Resistance to transforming growth factor beta-mediated inhibition is a well-known pathogenic mechanism in epithelial neoplasias. In a retrospective study, the expression of transforming growth factor beta receptors types I and II, cyclin D1, and the cyclin-dependent inhibitor p27kip, was analyzed by immunohistochemistry. Results were interpreted in the context of clinicopathological data. Patient follow-up ranged from 1 to 18 years, with a mean of 4 years. MATERIALS: Twenty conventional primary papillary carcinomas and their metastases were selected according to current pathologic criteria. Nonconventional papillary carcinomas (eg, tall-cell, columnar) were excluded from the analysis. RESULTS: Cyclin D1 was expressed more intensely in the tumor than in adjacent nonneoplastic parenchyma. Within a given tumor, however, there was significant heterogeneity in expression intensity and percentage of positive cells, particularly in metastases. Type I receptors were strongly expressed in 90% of tumors, while 80% of the tumors revealed low to no expression of type II receptors. In 10% of tumors, type I receptors were absent and type II receptors expressed. Simultaneous absence of both receptors was not observed. While p27kip was strongly expressed in nonneoplastic thyroid, it was not detected in any of the primary tumors or their metastases. CONCLUSIONS: The results strongly suggest that functional abnormalities in type II receptors result in increased levels of cyclin D1 and down-regulation of p27kip. This would maintain cells in a proliferative state and would promote tumor progression.

A mutation in the transforming growth factor beta type II receptor gene promoter associated with loss of gene expression.

Expression of transforming growth factor beta type II receptors (TbetaR-IIs) is either greatly decreased or absent in many tumors, implying that the loss of TbetaR-II function is one of the mechanisms leading to tumor development. In this report, we examine the expression of the TbetaR-II receptor in a squamous carcinoma cell line that expressed reduced levels of TbetaR-II mRNA. We found an A --> G mutation at position -364 of the 5' untranslated region of the TbetaR-II gene. This mutation results in significantly decreased transcriptional activity by the TbetaR-II gene promoter, suggesting that it is a primary mechanism of loss of TbetaR-II expression in this tumor cell line.

Missense mutations of the transforming growth factor beta type II receptor in human head and neck squamous carcinoma cells.

In this study, we report the occurrence of missense mutations of the transforming growth factor beta (TGF beta) type II receptor gene in two human squamous head and neck carcinoma cell lines. Both mutations are G:C-->C:G transversions, which result in the replacement of a glutamic acid by a glutamine, and of an arginine by a proline residue, respectively. Moreover, both are located at highly conserved sites within the serine-threonine kinase domain. One of the mutants appears to be defective in its autophosphorylation as well as in the transphosphorylation of the TGF beta type 1 receptor protein, whereas the second mutant appears to be constitutively activated. These are the first reported naturally occurring nucleotide substitution mutations in the T beta R-11 gene in human head and neck cancer cells, which may explain their resistance to TGF beta 1-mediated cell cycle arrest.

B7-1 expression by a non-antigen presenting cell-derived tumor.

The existence of a naturally occurring immunosurveillance against neoplastic cells is controversial. A difficulty with this concept is that tumor-specific antigen-reactive T cells would not be expected to become activated after encountering tumor cells, since T cells that bind to antigen in the absence of the costimulation provided by antigen-presenting cells may be inactivated. We studied a transgenic model of tumorigenesis where T cells reactive to a particular tumor-specific antigen are lost prior to the development of non-antigen-presenting cell-derived tumors; therefore, the tumors that develop are not subjected to immunosurveillance. We found that a tumor cell line derived from one such tumor expresses the T-cell costimulatory molecule B7-1, the expression of which is normally restricted to antigen-presenting cells. In addition, we found that several immortalized cell lines, which are nontumorigenic and thus have suffered only early genetic events in the tumorigenesis process, express B7. This suggests that a host cell can be induced to express surface B7-1 molecules after suffering an oncogenic insult, which might possibly be a primary mechanism of immunosurveillance against tumors.

Wild-type p53 tumor suppressor gene restores differentiation of human squamous carcinoma cells but not the response to transforming growth factor beta.

In order to clarify the role of the p53 tumor suppressor gene in controlling growth and differentiation of human epithelial cells, we transfected a wild-type p53 complementary DNA, driven by a dexamethasone-inducible mouse mammary tumor virus promoter, into SqCC/Y1 human head-and-neck squamous carcinoma cells. When treated with dexamethasone, 2 of 8 independent clones that contained integrated vector sequences expressed wild-type p53-specific mRNA as well as nuclear p53 protein. The highest p53 expressor (SqCC/Y1.53.5) was as resistant to inhibition of cell growth by transforming growth factor beta as control transfectants. Furthermore, these cells continued to proliferate in medium containing the combination of 2 mM Ca2+ and 10% (v/v) fetal bovine serum, which normally induces terminal differentiation in primary keratinocytes. However, under these same conditions, two of the essential proteins required for the formation of the cornified cell envelope were induced. First, in SqCC/Y1.53.1 and -.5 cells, the activity of membrane-associated keratinocyte-specific transglutaminase I increased to 3- to 5-fold higher levels than in control transfectants. Second, in SqCC/Y1.53.1 and -.5 cells, the envelope precursor, involucrin, increased to 5 to 8 times the levels attained in control transfectants. Thus, reexpression of wild-type p53 does not restore responsiveness of SqCC/Y1 carcinoma cells to growth inhibition but allows cells to reexpress the proteins required for the assembly of the cornified cell envelope.

Resistance of human squamous carcinoma cells to transforming growth factor beta 1 is a recessive trait.

Because most human squamous carcinoma cell lines of the aerodigestive and genital tracts are refractory to the antiproliferative action of transforming growth factor beta 1 (TGF beta 1) in vitro, we have begun to identify the causes for resistance of squamous carcinoma cell lines to TGF beta 1 by using somatic cell genetics. Two stable hybrid cell lines (FaDu-HKc.1 and FaDu-HKc.2) were obtained by fusing a TGF beta 1-resistant human squamous carcinoma cell line, FaDu-HygR, with a human papilloma virus 16-immortalized, TGF beta 1-sensitive, human foreskin keratinocyte cell line, HKc-neoR. Whereas TGF beta 1 did not inhibit DNA synthesis in parental FaDu-HygR cells, it reduced DNA synthetic activity of HKc-neoR, FaDu-HKc.1, and FaDu-HKc.2 cells by 75-85% (IC50, 2-5 pM). Although squamous carcinoma cells express lower than normal levels of TGF beta 1 type II receptors on their cell surface, TGF beta 1 type II receptor mRNA was detected in all four cell lines. Recessive genes involved in TGF beta 1 signaling may be localized to the distal portion of chromosome 18q, as this was the sole chromosomal region of homozygous deletion in parental FaDu-HygR cells. Furthermore, our previous observation that mutant p53 decreases sensitivity of keratinocytes to TGF beta 1 was supported by the finding that the level of the mutant p53 protein expressed by the hybrid cell lines was greatly reduced. In summary, TGF beta 1 resistance of FaDu cells appears to be recessive and is presumably due to the loss of one or more post-receptor elements of the signaling pathway.