La MMP2 est une protéinase stromale qui dégrade plusieurs éléments de la matrice extracellulaire et qui active d’autres MMPs dont la MMP9. La MMP14 active la MMP2 via l’inhibiteur de la pro-MMP2, le TIMP2. Cette étude avait pour buts de démontrer l’association entre la surexpression de la MMP2 et la récidive du CaP, d’évaluer l’influence de la MMP9, de la MMP14 et du TIMP2 sur cette association, puis de tester par un modèle murin l’influence de la MMP14 stromale sur la croissance tumorale. Nous avons analysé immunohistochimiquement 204 cas de CaP (T3NxM0) et avons étudié séparément les cellules cancéreuses, stromales et épithéliales bénignes (CEB), notamment selon le pourcentage d’expression des marqueurs (< 10% ou ≥ 10%). Le suivi médian est de 4,61 ans. La surexpression de la MMP9 dans les cellules cancéreuses est associée à un score de Gleason élevé (8-10) (p = 0,0009). Dans les CEB, la surexpression la MMP14 est associée au niveau de PSA sérique initial bas (≤ 20 ng/ml) (p = 0,0027). Le TIMP2 est protecteur (RR = 0,573, p = 0,0233) lorsque fortement exprimé dans les cellules stromales. La MMP2 augmente le risque de récidive lorsqu’exprimée par les cellules cancéreuses (RR = 1,549, p = 0,0027, test de tendance). L’étude de la croissance de tumeurs injectées à des souris nues/nues suggère que la MMP14 est associée à l’implantation tumorale. La MMP9 et la MMP14 seraient impliquées dans l’évolution du CaP alors que la MMP2 et le TIMP2 peuvent servir de marqueurs pronostiques pour les CaP T3NxM0. / Introduction: The matrix metalloproteinase 2 (MMP2) is associated with poor prognosis in many neoplasms. MMP14 activates MMP2 using pro-MMP2 specific inhibitor TIMP2 as a receptor. Activated MMP2 degrades extracellular matrix components such as collagen and gelatin, and activates other MMPs including MMP9 (gelatinase B). We therefore tested the influence of MMP9, MMP14 and TIMP2 expression on prostate cancer (Pca) disease-free survival and the association between MMP2, MMP9, MMP14 and TIMP2. Stromal MMP14 involvement in tumor growth was also tested. Material and methods: By immunohistochemistry, we analyzed 200 T3NxM0 Pca cases. We evaluated marker expression separately in cancer, stromal and benign epithelial (BE) cells according to a percentage scale (0, < 10, 10-50 and ≥ 50%) and to low (< 10%) or high (≥ 10%) expression of the markers. MCF7 cells were injected subcutaneously to nu/nu mice with MMP14 -/- fibroblasts and their growth was compared to MCF7 + MMP14 +/+ fibroblasts tumors. Results: Median follow-up was 4.61 years. MMP9 overexpression in cancer cells was associated with high Gleason score (8-10) (p = 0.0009). Low initial PSA serum levels (≤ 20ng/ml) were indirectly associated with MMP14 overexpression in BE cells (p = 0.0027) and with MMP9 overexpression in stromal (p = 0.0050) and BE cells (p = 0.0056). There was a decreased risk of Pca recurrence with high (≥ 10%) TIMP2 expression in stromal cells (hazard ratio (HR) = 0.573, p = 0.0233) and an increased risk of Pca recurrence with MMP2 expression by > 50% of BE cells (HR = 3.006, p = 0.0387). Increased risk of Pca recurrence was also observed with high MMP2 expression (HR = 1.549, p = 0.0027, trend test) and with the following combinations: low TIMP2 in stromal cells and high MMP2 in BE cells (HR = 4.121, p < 0.0001); high MMP2 in stromal cells and low TIMP2 in cancer cells (HR = 2.742, p = 0.0171). MCF7 studies suggest MMP14 stromal involvement in Pca implantation. Conclusions: MMP9 and MMP14 are involved mostly in Pca implantation. MMP2 and TIMP2 might be used as predictors of disease-free survival in T3NxM0 Pca.

Thesis (PhD)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: The "classic" prostate cell lines, DU145, PC-3 and LNCaP, have served as a valuable cell biological model for research into prostate cancer. However, their relevance may be limited because they derive from metastatic, and not from primary normal and tumour epithelium. The cell lines (1532T, 1535T, 1542T, 1542N and BPH-l) have been derived from primary benign and malignant human tumour prostate epithelium and may be more representative. Using these cell lines I have examined the role of basic cell damage responses (repair, checkpoint activation, apoptosis and associated signalling proteins, and the influence of androgen status) in cell inactivation, and its relevance to treatment. Numerous studies have suggested that loss of p53 function leads to resistance to chemotherapeutic agents and irradiation. It is shown here that the p53-inactive cell lines are, in fact, the most sensitive to chemotherapeutic agents such as etoposide, vinblastine and estramustine, whilst the p53 wild-type cell line, LNCaP, is the most radiosensitive. Notwithstanding the effects of p53 degradation by the HPV -16 E6 viral protein, the results on chemosensitivity raises the possibility that different chemotherapeutic agents may have different p53-dependent effects in different tumour cells. Androgen deprivation is demonstrated to sensitise prostate cancer cells to chemotherapeutic agents and it is shown that the hormone independent cell lines are the most chemosensitive. The LNCaP cell line displayed an increased resistance to apoptosis induced by etoposide and gamma irradiation, suggesting that androgens are capable of protection against both these DNA damaging agents. The major factors determining radiosensitivity in human tumour cell lines are known to be DNA double-strand break (dsb) induction and repair. In the prostate cell lines I find that cellular radiosensitivity correlates with the number of DNA double-strand breaks measured within 2 hours of irradiation, and that the more radioresistant cell lines show better repair competence. Conclusions as to the influence of androgen dependence on radiosensitivity and repair are not possible at this stage since only the LNCaP cell line was androgen sensitive. The fact that the 2 hour repair period can separate radiosensitive from radioresistant cells in 2 groups of human tumour cell lines highlights the role of non-homologous end-joining repair. This has implications for therapy, and is consistent with the clinical observation that prostate tumours can be successfully controlled by low dose rate-brachytherapy. To evaluate the role of apoptosis, cells were exposed to TD50 concentrations of chemotherapeutic drugs, and 60Co y-irradiation. Apoptosis was found to be low, overall, and ranged from 0.1% - 12.1%,3.0% - 6.0% and 0.1% - 8.5% for etoposide, estramustine and vinblastine, respectively. The percentage of cells undergoing druginduced apoptosis was, on average, higher in the tumour cell lines than in the normal cell lines. Gamma irradiation-induced apoptosis levels ranged from 1.3% - 7%. The LNCaP cell line yielded the lowest percentage of apoptotic cells after exposure. The l532T cell line yielded the highest percentage of apoptotic cells after exposure. Apoptotic propensity did not rank the cell lines according to their radiosensitivity. Immunoblotting demonstrated that the apoptosis-associated proteins, bax and bcl-2, are expressed at a basal level in all the cell lines tested, but no increase was detected after exposure to TD50 doses of etoposide, vinblastine and estramustine. The ratio of bax and bcl-2 also was not altered by DNA damage. No evidence was found that a correlation may exist between reproductive cell death and the expression of genes which control apoptosis. My results show that apoptosis is not a major mechanism of drug- or radiation-induced cell death in prostate cell lines. In conclusion, loss of p53 function and loss of androgen dependence was not found to be correlated with resistance of tumours to chemotherapeutic drugs. Cellular radiosensitivity was found to be correlated with the number of DNA double-strand breaks remaining after 2 hours of repair. The more radioresistant cell lines showed better repair competence. Apoptosis and genes affecting apoptosis, such as p53 and members of the bcl-2 family, do not seem to contribute significantly to the sensitivity of prostate cancer cells to anticancer drugs and irradiation. / AFRIKAANSE OPSOMMING: Die klassieke prostaat sellyne, DU145, PC-3 en LNCaP, het 'n waardevolle bydrae gemaak in die sel biologiese model in prostaat kanker. Die toepaslikheid daarvan mag egter beperk wees, aangesien hierdie sellyne afkomstig is van metastatiese, en nie van primêr normale en tumor epiteel nie. Die sellyne 1532T, 1535T, 1542T, 1542N en BPH-I is afkomstig van primêre benigne en maligne menslike prostaat tumor epiteel en mag moontlik meer verteenwoordigend wees. Deur van hierdie sellyne gebruik te maak, is die rolondersoek van die reaksie op basiese selskade (d.w.s. herstel, beheerpunt aktivering, apoptose en verwante sein proteïene, en die invloed van androgeen status) tydens die proses van sel inaktivering, asook die toepaslikheid ten opsigte van behandeling. Volgens verskeie studies lei die verlies aan p53 funksie tot weerstandigheid teen chemoterapeutiese middels en bestraling. Die resultate van hierdie studie toon dat die p53-onaktiewe sellyne egter die sensitiefste is vir chemoterapeutiese middels, soos etoposied, vinblastien en estramustien, terwyl die p53 natuurlike-tipe sellyn, LNCaP, die meeste radiosensitief is. Ten spyte van die invloed van p53 afbraak deur die HPV -16 E6 virale proteïen, dui die resultate van chemosensitiwiteit op die moontlikheid dat verskillende chemoterapeutiese middels verskillende p53-afhanklike effekte op verskillende tumorselle mag hê. Dit is bewys dat onttrekking van androgeen prostaat kankerselle sensitiseer teen chemoterapeutiese middels en dat hormoon-onafhanklike sellyne die hoogste chemosensitiwiteit vertoon. Die LNCaP sellyn vertoon 'n verhoogde weerstandigheid teen apoptose wat deur etoposied en y-bestraling geïnduseer is, wat 'n aanduiding is dat androgene beskerming kan bied teen beide hierdie DNA beskadigingsfaktore. Die belangrikste faktore wat die radiosensitiwiteit in menslike tumorselle bepaal, IS bekend dat dit die dubbelbande van DNA verbreek en herstel. Hierdie studie het aangetoon dat in prostaat sellyne die sellulêre radiosensitiwiteit korreleer met die aantal DNA dubbelband verbrekings binne 2 uur na bestraling, en dat die meer radioweerstandige sellyne beter herstelvermoë vertoon. Gevolgtrekkings oor die invloed van androgeen se afhanklikheid van radiosensitiwiteit en herstel kan egter nie op hierdie stadium gemaak word nie, aangesien slegs die LNCaP sellyn androgeenafhanklik was. Die feit dat die 2 uur herstelperiode 'n skeiding kan maak tussen radiosensitiewe en radioweerstandige selle in twee groepe menslike tumor sellyne, onderstreep die rol van herstel van nie-homoloë endverbindings. Dit hou implikasies in vir terapie, en stem ooreen met die kliniese waarnemings dat prostaat tumore suksesvol gekontroleer kan word deur lae intensiteit dosis bragiterapie. Ten einde die rol van apoptose te ondersoek, is selle blootgestel aan TD50 konsentrasies chemoterapeutiese middels, asook 60Co y-bestraling. Apoptose was oor die algemeen laag, en het gestrek van 0.1% tot 12.1%,3.0% tot 6.0% en 0.1% tot 8.5% vir etoposied, estramustien en vinblastien onderskeidelik. Die persentasie selle wat middel geïnduseerde apoptose ondergaan het, was gemiddeld hoër in tumor sellyne as in normale sellyne. Die waardes van apoptose geïnduseer deur y-bestraling het gewissel van 1.3% tot 7.0%. Die LNCaP sellyn het die laagste persentasie apoptotiese selle na bestraling gelewer, terwyl die 1532 r sellyn die hoogste persentasie gelewer het. Die volgorde van die radiosensitiwiteit van die sellyne was nie waarneembaar in hulle geneigdheid tot apoptose nie. Immunoblots het aangetoon dat die apoptose-geassosieerde proteïene, bax en bcl-2, uitgeskei word teen 'n basisvlak in al die sellyne wat getoets is, maar dat geen verhoogde uitskeiding waarneembaar was na blootstelling aan TD50 dosisse etoposied, vinblastien en estramustien nie. Die verhouding van bax en bcl-2 is ook nie beïnvloed deur DNA beskadiging nie. Dit blyk daarom dus onwaarskynlik dat daar 'n korrelasie bestaan tussen reproduktiewe seldood en die uitskeiding van gene wat apoptose beheer. Die resultate dui daarop dat apoptose me 'n belangrike meganisme vir middel- of bestralingsgeïnduseerde seldood in prostaat sellyne is nie.

Background: Prostate cancer is the most common type of cancer in Sweden. The three primary treatment types for prostate cancer are prostatectomy, radiotherapy and different types of endocrine therapy. With all treatments mentioned above comes adverse effects that may have big effects on the person treated. Aim: The aim of this study was to highlight men´s experiences of the adverse effects that comes with the treatment for prostate cancer. Method: The research method employed was a literature study based on eleven qualitative articles. The method of analysis was done according to Friberg five-step analysis of qualitative articles and through the analysis, six themes emerged. Results: The themes were A feeling of emotional imbalance, Not prepared enough, The experience of loosing control, Feeling of diminished masculinity, The experience of a feminized body and An altered identity. Conclusion: The result showed that men experience adverse effects of the prostate cancer treatment as difficult in many ways. The changes to the body and mental well-being tend to be difficult to deal with, and the men need relevant information prior to treatment to give them time to adjust to their new life.

Background Screening for prostate cancer is debated, there is conflicting data on the net benefit of screening. Men who consider screening need to be informed on the pros and cons. Rehospitalization after surgery can be used as an indicator of general quality of care. For radical prostatectomy, little is known on the readmission rate after surgery. Men diagnosed with low- and intermediate-risk prostate cancer have low prostate-cancer specific mortality. However, adverse effects after curative treatment can be severe and decrease quality of life. Curative treatments for prostate cancer differ mainly in the pattern of adverse effects but detailed analysis of long-term adverse effects is lacking. The aim of this thesis was to assess the perioperative quality of radical prostatectomy and the risk of adverse effects after curative treatment for prostate cancer. Material and Methods In this thesis, data from the National Prostate Cancer Register (NPCR) and other nationwide Swedish registers were used. By use of the Swedish personal identity number, NPCR was cross-linked to other registers creating Prostate Cancer data Base Sweden (PCBaSe), a large dataset for research. Results The proportion of men who had received information on the pros and cons of screening for prostate cancer with PSA testing was low (14%) indicating that the majority of men who were screened did not make an informed decision. The risk of rehospitalization within 90 days after radical prostatectomy was approximately 10% and similar after retropubic and robot-assisted radical prostatectomy. Compared to controls, there was an increased risk of adverse effects after both radiotherapy and radical prostatectomy up to twelve years after treatment and the overall risk was quite similar after retropubic and robot-assisted radical prostatectomy. Conclusion Improved information to men on the pros and cons of PSA screening is warranted. The risk of adverse effects was elevated up to 12 years after curative treatment for prostate cancer. The pattern of adverse effects was different after radiotherapy and radical prostatectomy but quite similar after retropubic and robot-assisted radical prostatectomy.

Le cancer de la prostate (CaP) est actuellement le cancer le plus fréquent en France et constitue l'une des principales causes de décès par cancer chez l'homme dans les pays industrialisés. Un tiers des patients avec un CaP à priori localisé auront déjà des micro-métastases au moment du traitement local. Ces patients qui répondent dans un premier temps à la castration (hormonothérapie) seront cependant en échappement hormonal dans les 2 ans qui suivent. Récemment, plusieurs essais cliniques de phase III ont rapporté un gain de survie avec la chimiothérapie à base de docétaxel dans les CaPs métastatiques résistants à la castration. Néanmoins, la survie n'est prolongée que de 2 ou 3 mois et de nouvelles approches thérapeutiques ciblant des voies de signalisation spécifiques sont donc nécessaires. Les travaux réalisés au cours de cette Thèse ont permis tout d'abord de montrer, grâce à l'utilisation de TMAs, que la surexpression de TP53INP1, une protéine de réponse au stress, était un facteur de mauvais pronostic dans le CaP, prédictif notamment du risque de rechute biologique. Nous avons ensuite pu montrer grâce à des xénogreffes de cellules tumorales (LNCaP) que les taux d'ARNm de TP53INP1 diminuaient durant l'hormonothérapie et que TP53INP1 était de nouveau significativement surexprimée dans les tumeurs résistantes à la castration. Nous avons développé et déposé un brevet pour un oligonucléotide antisens (ASO) inhibant TP53INP1. Le traitement in vitro des lignées cellulaires hormonosensibles LNcaP et hormono-résistantes C4-2 par l'ASO induit une diminution d'expression de la protéine TP53INP1, inhibe la prolifération cellulaire et induit une augmentation de l'apoptose. / Prostate cancer (PC) is the most common malignancy in France and one of the most frequent leading causes of cancer-related death in men in industrialized countries. Even with aggressive screening, approximately one-third of patients believed to have localized PC will already have micro-metastatic disease at the time of definitive local therapy. These patients initially respond to androgen ablative therapy, but with time, their tumors ultimately become unresponsive and recur within 2 years as castration-resistant prostate cancer (CRPC). Recently, docetaxel-based regimens have shown improved survival in men with CRPC in phase III studies. However, the median overall survival was prolonged for only 2-3 months, and thus development of new therapeutic approaches that target relevant signaling pathways are essential to restore the androgen-sensitivity of CRPC. We showed, using tissue micro-array (TMA) analysis, that over-expression of Tumor Protein 53-Induced Nuclear Protein 1 (TP53INP1), a cell stress response protein, is a worse prognostic factor in PC, particularly predictive of biological cancer relapse. We also we found that TP53INP1 protein expression decreases during castration therapy (CT) and significantly increases in human CRPC. TP53INP1 mRNA was also significantly increased in castration-resistant (CR) tumors of LNCaP xenograft compared to the castration-sensitive (CS) taken before CT. We developed and world-wide patented one antisense oligonucleotide (ASO) targeting TP53INP1 (PCT/IB2011/054555). Treatment of LNCaP and C4-2 cells in vitro with TP53INP1 ASO downregulates TP53INP1 protein level, inhibits proliferation and induces apoptosis.

Le cancer de la prostate (CaP) est le cancer le plus fréquent chez l'homme et représente la deuxième cause de mortalité par cancer. Cette pathologie est sensible aux androgènes des stades localisés aux stades métastatiques. Après le traitement des formes avancés de ce cIl est admit aujourd'hui que les androgènes seuls ne sont pas suffisants pour déclencher le cancer de la prostate. En effet, le rôle des œstrogènes dans la carcinogenèse prostatique est suggéré par plusieurs études. L'activation de la voie de signalisation Hedgehog (Hh) joue un rôle important dans le développement de plusieurs cancers, y compris le CaP. Une meilleure compréhension des mécanismes qui régulent l'activation de cette voie dans le CaP est nécessaire afin de définir de nouvelles stratégies thérapeutiques plus efficaces.Dans ce travail, nous mettons en évidence l'interaction entre la voie Hh et les hormones stéroïdiennes dans les cellules prostatiques. Nous avons observé : i) une activation de la voie Hh par l'œstrogène (sulfate d'œstrone (SE1)), atténuée par l'anti-œstrogène (ICI) et par l'inhibiteur de la voie Hh (KAAD-cyclopamine), ii) une régulation négative de la voie Hh par l'androgène (dihydrotestostérone (DHT)) et l'œstrogène (17β-œstradiol (E2)). Nous avons démontré que l'inhibition de la voie Hh induite par DHT et E2 est dépendante des récepteurs des androgènes (RA). Cependant, l'effet de SE1 sur la voie Hh pourrait être dépendante des récepteurs des œstrogènes (ER). Enfin, nous avons observé une inhibition de l'activité des RA par KAAD-cyclopamine. Les dérivés de cyclopamine pourraient donc représenter une nouvelle classe d'agents thérapeutiques ciblant le RA dans le cancer de la prostate. Une meilleure caractérisation des cibles potentielles de ces molécules semble être intéressante. / Prostate cancer (PCa) is the most frequent male malignancy and the second most common cause of cancer-related death in men. This cancer is androgen sensitive in its development and progression to metastatic disease. Despite this, increasing evidence suggest that androgens alone are not able to induce PCa and estrogen signaling has a key role in prostate cancer progression. Hedgehog (Hh) pathway activation is important in the growth and development of various carcinomas including PCa. A better understanding of Hh pathway regulating mechanisms in PCa is important in order to identify new therapeutic strategies for this pathology. In this study we investigate the interaction between Hh pathway and steroid hormones in prostate cells. We showed: i) Hh pathway activation by the estrogen (estrone sulfate E1S), attenuated by the anti-estrogen (ICI) and by the Hh pathway inhibitor (KAAD-cyclopamine) ii) Hh pathway negative regulation by the androgen (dihydrotestostérone (DHT)) and the estrogen (17β-estradiol (E2)). Moreover, we showed that Hh pathway inhibition is androgen receptor (AR) dependent. However, E1S effect on this pathway might be estrogen receptor (ER) dependent. Finally, our results suggest that targeting AR signaling by cyclopamine derivatives could be promising therapeutic alternative in prostate cancer, which needs a further investigation.

De nombreuses données expérimentales et cliniques ont montré l'importance des cellules Natural Killer (NK) dans l'immunosurveillance antitumorale. Les stratégies thérapeutiques basées sur les cellules NK pourraient donc être une alternative de choix dans le traitement de certains types de cancers. Nous avons focalisé notre étude sur deux types de cancer incurables malgré les récents progrès thérapeutiques : la leucémie lymphoïde chronique B (LLC-B) et le cancer de la prostate. Le but de notre étude est une meilleure compréhension des mécanismes mis en place par les cellules B leucémiques et les cellules tumorales prostatiques pour échapper à la réponse antitumorale des cellules NK. La connaissance de ces mécanismes d'échappement est un pré-requis indispensable à l'utilisation des cellules NK dans les thérapies antitumorales. Concernant la LLC-B, nos résultats suggèrent que les cellules NK de patients, fonctionnellement compétentes, ne peuvent pas initier une réaction immunitaire appropriée envers les cellules B leucémiques due au manque de reconnaissance de ces dernières. Concernant le cancer de la prostate, nos données préliminaires montrent que les cellules NK circulantes de patients sont également fonctionnellement compétentes, quelque soit le stade de la maladie, malgré la diminution significative de l'expression du récepteur NKp30. Ainsi, le degré d’immunogénicité des cellules B leucémiques et celui des cellules tumorales prostatiques devra être autant pris en compte que la fonctionnalité des cellules NK dans les stratégies visant à optimiser l'activité antitumorale de ces dernières. / Many experimental and clinical data have enlightened the importance of Natural Killer (NK) cells in tumor immunosurveillance. Therapeutic strategies based on NK cells could be an alternative in the treatment of certain cancers. We focused our study on two types of incurable cancers despite recent advances in treatment: B chronic lymphocytic leukemia (B-CLL) and prostate cancer. The aim of our study is a better understanding of the mechanisms set up by leukemic B cells and prostate cancer cells to escape from NK antitumor response. The knowledge of these escape mechanisms is an essential prerequisite to the use of NK cells in antitumor therapies. Regarding B-CLL, our results suggest that NK cells, although functionally competent, can not initiate an appropriate immune response against leukemic B cells due to a lack of recognition of the latter. Concerning the prostate cancer, our preliminary data show that circulating NK cells are functionally competent, whatever the stage of disease, despite the significant decrease in expression of the receptor NKp30. Thus, the degree of immunogenicity of leukemic B cells and of the prostate cancer cells must be taken into account as well as the functionality of NK cells in strategies aiming at improving NK antitumor activity.

Le tissu adipeux périprostatique (TAPP) est potentiellement impliqué dans l’agressivité du cancer de la prostate (CaP). Nous avons identifié une association négative entre un taux élevé d’acide linoléique (AL) et d’acide eicosapentaénoïque (EPA) dans le TAPP, l’agressivité de la maladie et la migration des cellules cancéreuses in vitro. La migration des cellules tumorales est liée au phénomène de transition épithélio-mésenchymateuse (TEM), induit par des facteurs du microenvironnement, dont le TGFb et l’hypoxie. Nous avons démontré dans le CaP la signification clinique de la TEM et son facteur de transcription clé Zeb1, dont l’expression augmente lors de la progression du cancer avec un impact sur la survie. Nous avons ensuite montré que l’incorporation de l’AL et de l’EPA dans la membrane plasmique des cellules cancéreuses prostatiques inhibe la migration cellulaire et l’expression de Zeb1 induite par le TGFb et l’hypoxie, in vitro et ex vivo. Nous avons également démontré que l’expression de Zeb1 est dépendante d’une entrée SOCE, impliquant le canal SK3, et régulée par l’AL et l’EPA. Cette régulation de l’entrée calcique par l’AL et l’EPA a également été observée ex vivo dans des explants de CaP humains. / Periprostatic adipose tissue (PPAT) has been suggested to be involved in the modulation of prostate cancer (PCa) progression. We demonstrated herein that low contents of linoleic acid (LA) and eicosapentaenoic acid (EPA) in PPAT are associated with PCa aggressiveness and cancer cell migration in vitro. Cell migration is linked to the process of epithelial-mesenchymal transition (EMT), induced by microenvironmental factors, such as TGFb and hypoxia. We demonstrated in PCa the clinical value of EMT and its key transcription factor Zeb1, which expression increases with the stages of PCa progression, with an impact on survival. Then we have shown, in vitro and ex vivo, that the incorporation of LA and EPA into the plasma membrane of PCa cells inhibits TGFb- and hypoxia-induced cell migration and Zeb1 expression. We also demonstrated that Zeb1 expression is dependent on SOCE influx, involving SK3 channel, and regulated by LA and EPA. This regulation of calcium entry by LA and EPA has also been observed ex vivo in human PCa slices.

INTRODUÇÃO: O diagnóstico do câncer de próstata em pacientes com níveis séricos do antígeno prostático específico persistentemente elevados após biópsia prostática negativa representa um grande desafio para urologistas e patologistas. A baixa especificidade do antígeno prostático específico e a baixa sensibilidade da biópsia prostática guiada por ultra-som são os maiores obstáculos observados na prática clínica. Apesar do uso de diversos métodos para prever a presença de câncer na glândula, nenhum deles tem precisão absoluta, obrigando os pacientes a realizar novas biópsias. Neste contexto, a descoberta de novos marcadores diagnósticos para o câncer da próstata tornase necessária. OBJETIVO: Avaliar o valor diagnóstico da expressão de seis genes no tecido prostático de pacientes com câncer de próstata clinicamente localizado. MÉTODOS: O estudo consistiu na análise de 50 pacientes com diagnóstico de câncer da próstata, submetidos à prostatectomia radical por doença localizada. A seleção dos genes foi baseada em um estudo prévio que utilizou a tecnologia de microarray (Agilent Technologies 44k whole human genome, two-color) em pacientes com câncer de próstata, divididos de acordo com as características clínico-patológicas. Entre os 4.147 genes com expressão diferenciada entre os casos de câncer de próstata, seis genes (PSMA, TMEFF2, GREB1, TH1L, IgH3 e PGC) foram selecionados. Estes genes foram então testados quanto a seu valor diagnóstico no câncer da próstata através da técnica de reação em cadeia da polimerase quantitativa com transcriptase reversa. Na primeira etapa do estudo, amostras de tecido maligno de 33 pacientes com câncer de próstata foram avaliadas. O grupo controle foi composto de nove pacientes com hiperplasia benigna da próstata. Na segunda etapa do estudo foram analisadas amostras de tecido benigno dos demais 17 pacientes com câncer da próstata. O mesmo grupo controle foi utilizado para comparação. RESULTADOS: A análise demonstrou que o PSMA estava super-expresso (em média nove vezes) e o PGC sub-expresso (em média de 1,3 x 10-4 vezes) no tecido neoplásico de todos os casos de câncer quando comparados com os casos de hiperplasia benigna. Os demais genes demonstraram um padrão de expressão variado, não permitindo a diferenciação entre os tecidos malignos e benignos. Quando estes resultados foram testados no tecido prostático benigno dos pacientes com câncer, o PGC manteve o mesmo padrão de expressão em todos os casos e o PSMA, apresentou-se super-expresso em 88% dos pacientes (média de 12 vezes), em relação aos casos de hiperplasia benigna. CONCLUSÃO: A combinação da super-expressão do PSMA e sub-expressão do PGC no tecido prostático pode representar uma evidência objetiva de presença de Cap. Análises clínicas prospectivas adicionais são necessárias para confirmar estes resultados / Introduction and objective: Prostate cancer (PCa) diagnosis in men with persistently increased PSA after a negative initial prostate biopsy has become a great challenge for urologists and pathologists. Despite the use of several methods to increase the sensitivity of prostate biopsy, the false-negative rates remain substantial, leading many patients to undergo repeated procedures. We analyzed the diagnostic value of six genes in the prostatic tissue of patients with clinically localized PCa, in order to predict the presence of cancer. Methods: The study was comprised by 50 patients with clinically localized PCa who underwent radical prostatectomy. Gene selection was based on a microarray analysis of patients with PCa. Among the 4,147 genes with different expressions between two groups, six genes (PSMA, TMEFF2, GREB1, TH1L, IgH3 and PGC) were selected. These genes were tested for its cancer diagnostic role using the quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) method. In the first part of the study, malignant tissue samples from 33 patients were analyzed, and in the second part we analyzed benign tissue samples of the other 17 patients with PCa. The control group was comprised of prostatic tissue samples of patients with benign prostatic hyperplasia (BPH). Results: The analysis of malignant prostatic tissue by qRTPCR showed that PSMA was over-expressed (mean nine times) and PGC was under-expressed (mean 1.3 x 10-4 times) in all cases when compared to BPH. The other four tested genes showed a variable expression pattern not allowing a differentiation between benign and malignant cases. When we tested these results in the benign prostate tissues from patients with PCa, PGC maintained the expression pattern, and PSMA, despite over-expression in most cases (mean 12 times), two cases (12%) presented under-expression. Conclusions: PGC under-expression and PSMA over-expression in the tissue may represent an objective evidence of prostate cancer and constitute a powerful adjunctive method in patients with negative prostate biopsy. Further prospective clinical analyses are necessary to confirm theses results

Notre étude a porté, d'une part sur l'effet du bicalutamide, un inhibiteur du récepteur aux androgènes, sur la réponse de trois lignées de cancer de prostate en association avec les rayonnements ionisants, d'autre part sur la recherche d'une corrélation entre l'expression des microARN miR-210 et miR-373 sur la tolérance à l'hypoxie et la réponse au rayonnement.Nous montrons que le bicalutamide induit un effet cytostatique et cytotoxique dans la lignée LNCaP, qui exprime le récepteur aux androgènes. Les lignées DU145 et PC3, qui n’expriment pas ou peu le récepteur, sont sensiblement plus résistantes mais sont cependant affectées par les concentrations élevées de bicalutamide. Cette sensibilité résiduelle suggère l'existence d'un mécanisme secondaire, indépendant de la voie de signalisation du récepteur aux androgènes. L'inhibition de la prolifération produite par le bicalutamide s'accompagne d'un blocage du cycle cellulaire en phase G1 avec une augmentation de l’expression de la protéine p27 et une diminution de l’expression de la protéine HER2. L'association concomitante au bicalutamide se traduit par un effet radioprotecteur dans la lignée LNCaP. Cette observation nous conduit à déconseiller l’association concomitante du bicalutamide avec la radiothérapie, notamment en cas d’irradiation hypofractionnée.Facteur bien connu de radiorésistance dans les tumeurs solides, l'hypoxie est associée à un mauvais pronostic dans les cancers de la prostate. Nos données montrent qu'en sus de l'induction de marqueurs classiques comme HIF-1α, CA9 et VEGF, l'hypoxie promeut l’expression du microARN miR-210, (mais non de miR-373) indépendamment de l’expression du récepteur aux androgènes. Les données suggèrent que miR-210, dont l'expression apparaît corrélée à la résistance à l'hypoxie, pourrait constituer un bon biomarqueur pronostique dans le cancer de la prostate. En revanche, l’inhibition de l’expression de miR-210 n'a aucun effet sur la radiosensibilité des cellules en condition d’hypoxie. / The first aim of our study was to evaluate the effect of the association between bicalutamide, an androgen receptor inhibitor, and ionizing radiation in three prostate cancer cell lines. The second aim was to examine a possible a correlation between the expression of miR-210 or miR-373, the tolerance to hypoxia tolerance and the responses to radiation.We found that bicalutamide produced cytostatic and cytotoxic effects in the androgen receptor- positive LNCaP cell line. The androgen receptor-negative DU145 and PC3 cell lines were more resistant to bicalutamide. However, these cell lines were affected by high bicalutamide concentration with the same endpoints as for LNCaP cells. The inhibition of proliferation by bicalutamide was associated with G1 cell cycle phase arrest, increased expression of p27KIP1 protein, and decreased expression of HER2 protein. Last but not least, bicalutamide elicited a marked radioprotective effect in LNCaP cells when associated with concomitant irradiation. This result suggests that bicalutamide and radiotherapy should not be delivered in close temporal proximity, especially in case of hypofractionated radiotherapy protocols.Hypoxia is a well known radioresistance factor in tumors and is associated with a bad prognosis in prostate cancer. In this study, we found that hypoxia promotes the expression of HIF-1α, CA9, VEGF and miR-210 but not miR-373 in prostate cancer cell lines irrespective of their androgen receptor status.Our findings suggest that miR-210 expression is correlated with resistance to hypoxia and could be used as a prognostic marker in prostate cancer. Conversely, miR-210 inhibition did not impact the radiation susceptibility of PC3 prostate cancer cell line under hypoxia.