Role of Mc1r in UV-induced melanoma in animal models

The role of UV and pigmentation are very difficult to control for in human studies, and mechanisms difficult to infer based on statistical association with melanoma. The animal models are not representative of the human situation. But on the other hand, animal studies can be useful for basic studies that will ultimately help in building up a picture of the overall network of in vivo cellular behavior and intra and inter cellular pathways contributing to melanoma progression and the effects (or not) of UV radiation in individuals with MC1R variants. This review describes that, although the Mc1r is a determinant of coat color phenotype as the MC1R is a determinant of hair and skin color in humans, deficiency of the Mc1r in mice is associated with a paradoxical lower incidence of melanoma

Neurofibromatosis type 1 with interstitial pulmonary lesions diagnosed in adult patient. A case study and literature review

Chory, lat 43 u którego na podstawie kryteriów klinicznych rozpoznano nerwiakowłókniakowatość typu 1 (NF1, choroba van Recklinghausena), został skierowany na oddział chorób płuc w celu przeprowadzenia diagnostyki przyczyn pogorszenia tolerancji wysiłku fizycznego oraz etiologii torbielowatych zmian w płucach uwidocznionych w tomografii komputerowej wysokiej rozdzielczości (HRCT). Od dzieciństwa pacjent był leczony z powodu padaczki, rozpoznano także niedomykalność zastawki trójdzielnej III stopnia, nie stwierdzając nadciśnienia płucnego w trakcie cewnikowania prawego serca. Ostatecznie przyjęto, że w omawianym przypadku zmiany śródmiąższowe w płucach są związane z chorobą zasadniczą i wymagają dalszej obserwacji klinicznej. Obserwowane pogorszenie tolerancji wysiłku fizycznego było związane z towarzyszącym zakażeniem układu oddechowego bakteriami Klebsiella oxytoca i Staphylococcus auresus u chorego za zmianami torbielkowatymi w płucach i niedomykalnością zastawki trójdzielnej bez współistnienia nadciśnienia w tętnicy płucnej. W doniesieniu omówiono kryteria rozpoznania NF1, a także kontrowersje dotyczące współistnienia śródmiąższowych zmian płucnych w obrazie choroby.A case of a 43-year-old man with clinically diagnosed neurofibromatosis type I (NF-1, von Recklinghausen disease), was referred to a lung disease unit in order to diagnosis of worsening tolerance to physical effort, and aetiology of radiological cystic lesions in the lungs, seen in the high-resolution computed tomography (HRCT). Since childhood the patient has been treated for epilepsy, and a 3rd degree tricuspid valve incompetence, without pulmonary hypertension was detected during right heart catheterization. Finally, the interstitial pulmonary lesions were attributed to the primary disease, and it was said they need further clinical observation in order to determine their dynamics. The observed deterioration in patient’s tolerance to physical effort was connected to the accompanying infection of the respiratory system with Klebsiella oxytoca and Staphylococcus aureus, with cystic lesions in lungs and tricuspid valve incompetence. The report describes the criteria for NF-1 diagnosis, as well as points out the controversies of coexistence of interstitial pulmonary lesions in the clinical picture of the disease

RIPK4 downregulation impairs Wnt3A-stimulated invasiveness via Wnt/β\beta-catenin signaling in melanoma cells and tumor growth in vivo

Purpose The role of Wnt signaling in oncogenesis and drug resistance is well known. Receptor-interacting protein kinase (RIPK4) contributing to the increased activity of many signaling pathways, including Wnt/$\beta$-catenin, may be an important target for designing new drugs for metastatic melanoma, but its role in melanoma is not fully understood. Methods We tested the effect of genetic manipulation of RIPK4 (CRISPR/Cas9) on xenograft growth. In addition, immunohistochemistry was used to detect active $\beta$-catenin, Ki67 and necrosis in xenografts. Wnt signaling pathway activity was examined using Western blot and Top-Flash. The effect of RIPK4 knockout on melanoma cells in vitro stimulated Wnt3A on wound overgrowth, migration and invasion ability was then evaluated. Results Our study showed that CRISPR/Cas9-mediated RIPK4 knockout (KO) significantly reduced tumor growth in a mouse model of melanoma, particularly of WM266.4 cells. RIPK4 KO tumors exhibited lower percentages of $Ki67^{+}$ cells as well as reduced necrotic area and decreased levels of active $\beta$-catenin. In addition, we observed that RIPK4 knockout impaired Wnt3A-induced activation of LRP6 and $\beta$-catenin, as manifested by a decrease in the transcriptional activity of $\beta$-catenin in Top-Flash in both tested melanoma cell lines, A375 and WM266.4. Prolonged incubation (48 h) with Wnt3A showed reduced level of MMP9, C-myc, and increased SOX10, proteins whose transcription is also dependent on $\beta$-catenin activity. Moreover, RIPK4 knockout led to the inhibition of scratch overgrowth, migration and invasion of these cells compared to their controls. Conclusion RIPK4 knockdown inhibits melanoma tumor growth and Wnt3A stimulated migration and invasion indicating that RIPK4 might be a potential target for melanoma therapy

Deciphering the functional role of RIPK4 in melanoma

The receptor-interacting protein kinase 4 (RIPK4) plays an important role in the development and maintenance of various tissues including skin, but its role in melanoma has not been reported. Using patient-derived cell lines and clinical samples, we show that RIPK4 is expressed in melanomas at different levels. This heterogenous expression, together with very low level of RIPK4 in melanocytes, indicates that the role of this kinase in melanoma is context-dependent. While the analysis of microarray data has revealed no straightforward correlation between the stage of melanoma progression and RIPK4 expression in vivo, relatively high levels of RIPK4 are in metastatic melanoma cell lines. RIPK4 down-regulation by siRNA resulted in the attenuation of invasive potential as assessed by time-lapse video microscopy, wound-healing and transmigration assays. These effects were accompanied by reduced level of pro-invasive proteins such as MMP9, MMP2, and N-cadherin. Incubation of melanoma cells with phorbol ester (PMA) increased PKC-$1\beta$ level and hyperphosphorylation of RIPK4 resulting in degradation of RIPK4. Interestingly, incubation of cells with PMA for short and long durations revealed that cell migration is controlled by the NF-$\kappa$ signaling in a RIPK4-dependent ($RIPK4^{high}$) or independent ($RIPK4^{low}$) manner depending on cell origin (distant or lymph node metastasis) or phenotype (mesenchymal or epithelial)

Prevalence of overweight, obesity and underweight among 3rd grade students of primary schools taking into account regional differences

WSTĘP. Zarówno nadmiar, jak i niedobór masy ciała wpływa negatywnie nie tylko na zdrowie i rozwój dzieci i młodzieży, ale również na zdrowie w życiu dorosłym, zwiększając ryzyko wystąpienia przewlekłych chorób niezakaźnych i niesprawności. Na stan odżywienia wpływa wiele czynników, a częstość występowania zaburzeń stanu odżywienia u dzieci i młodzieży narasta w wielu krajach na świecie i w Europie, w tym także w Polsce. MATERIAŁ I METODY. Badaniem przeprowadzonym w 2010 roku objęto łącznie 1255 uczniów w wieku 9 lat (627 dziewcząt i 628 chłopców) z terenu pięciu województw: mazowieckiego, podkarpackiego, opolskiego, pomorskiego i wielkopolskiego. Na podstawie pomiarów wysokości i masy ciała dzieci obliczono wskaźnik masy ciała (BMI). Stan odżywienia oceniono według kryteriów Cole’a i wsp. WYNIKI. Niedobór masy ciała stwierdzono u 11,5% dziewcząt i 8% chłopców, nadwagę u 18,7% dziewcząt i 17,2% chłopców, zaś otyłość u 4,1% dziewcząt i 6,5% chłopców. Największy odsetek otyłych dzieci występował w województwach mazowieckim i pomorskim, zaś dzieci z nadwagą — w województwach mazowieckim i opolskim. Najniższy odsetek dzieci z nadwagą i otyłością odnotowano w województwie podkarpackim. Nie zaobserwowano znaczących różnic w występowaniu niedoboru masy ciała między województwami. WNIOSKI. Stopień występowania nadwagi i otyłości u dzieci w poszczególnych regionach kraju był zróżnicowany. Największą częstotliwość występowania nadwagi i otyłości stwierdzono w województwie mazowieckim, a najniższą — w podkarpackim. We wszystkich objętych badaniem województwach częstość występowania nadmiernej masy ciała była wyższa niż występowania niedoboru masy ciała. Analiza regionalnych różnic w zakresie częstości występowania otyłości, nadwagi i niedoboru masy ciała u dzieci i młodzieży może wskazać kierunek ogólnopolskich i lokalnych działań mających na celu zmniejszenie rozbieżności wynikających ze stanu odżywienia.INTRODUCTION. Obesity, overweight and underweight affects not only health and development of children and adolescents, but also affects health in adulthood by increasing the risk of chronic noncommunicable diseases and disability. The nutritional status is affected by many factors and the incidence of nutritional disorders in children and adolescents is growing in many countries around the world and Europe, including Poland. Material and methods. The study conducted in 2010 covered a total of 1255 students aged 9 years (627 girls and 628 boys) from the area of five provinces of Poland: Masovian, Subcarpathian, Opole, Pomeranian and Greater Poland. Based on measurements of high and weight of children the body mass index was calculated. Nutritional status was assessed according to criteria of Cole et al. RESULTS. Underweight was found in 11.5% of girls and 8% of boys, overweight in 18.7% of girls and 17.2% of boys, obesity in 4.1% of girls and 6.5% of boys. The highest percentage of obese children has appeared in Masovian and Pomeranian provinces, while overweight children in Masovian and Opole provinces. The lowest percentage of children with overweight and obesity was observed in Subcarpathian province. There were no significant differences in the prevalence of weight deficiency among regions. CONCLUSIONS. The degree of overweight and obesity among children in different regions of Poland was varied. The highest incidence of overweight and obesity were found in Masovian province and the lowest in the Subcarpathian province. In all provinces surveyed, the incidence of excessive body weight was higher than the prevalence of underweight. Analysis of regional differences in the prevalence of obesity, overweight and underweight in children and adolescents may indicate the direction of national and local actions to reduce inequalities resulting from nutritional status

Prolonged idasanutlin (RG7388) treatment leads to the generation of p53-mutated cells

The protein p53 protects the organism against carcinogenic events by the induction of cell cycle arrest and DNA repair program upon DNA damage. Virtually all cancers inactivate p53 either by mutations/deletions of the TP53 gene or by boosting negative regulation of p53 activity. The overexpression of MDM2 protein is one of the most common mechanisms utilized by p53wt cancers to keep p53 inactive. Inhibition of MDM2 action by its antagonists has proved its anticancer potential in vitro and is now tested in clinical trials. However, the prolonged treatment of p53wt cells with MDM2 antagonists leads to the development of secondary resistance, as shown first for Nutlin-3a, and later for three other small molecules. In the present study, we show that secondary resistance occurs also after treatment of p53wt cells with idasanutlin (RG7388, RO5503781), which is the only MDM2 antagonist that has passed phase II and entered phase III clinical trials, so far. Idasanutlin strongly activates p53, as evidenced by the induction of p21 expression and potent cell cycle arrest in all the three cell lines tested, i.e., MCF-7, U-2 OS, and SJSA-1. Notably, apoptosis was induced only in SJSA-1 cells, while MCF-7 and U-2 OS cells were able to restore the proliferation upon the removal of idasanutlin. Moreover, idasanutlin-treated U-2 OS cells could be cultured for long time periods in the presence of the drug. This prolonged treatment led to the generation of p53-mutated resistant cell populations. This resistance was generated de novo, as evidenced by the utilization of monoclonal U-2 OS subpopulations. Thus, although idasanutlin presents much improved activities compared to its precursor, it displays the similar weaknesses, which are limited elimination of cancer cells and the generation of p53-mutated drug-resistant subpopulations

A melanin-independent interaction between Mc1r and Met signalling pathways is required for HGF-dependent melanoma

Melanocortin 1 receptor (MC1R) signaling stimulates black eumelanin production through a cAMP-dependent pathway. MC1R polymorphisms can impair this process, resulting in a predominance of red phaeomelanin. The red hair, fair skin and UV sensitive phenotype is a well-described melanoma risk factor. MC1R polymorphisms also confer melanoma risk independent of pigment. We investigated the effect of Mc1r deficiency in a mouse model of UV-induced melanoma. C57BL/6-Mc1r+/+-HGF transgenic mice have a characteristic hyperpigmented black phenotype with extra-follicular dermal melanocytes located at the dermal/epidermal junction. UVB induces melanoma, independent of melanin pigmentation, but UVA-induced and spontaneous melanomas are dependent on black eumelanin. We crossed these mice with yellow C57BL/6-Mc1re/e animals which have a non-functional Mc1r and produce predominantly yellow phaeomelanin. Yellow C57BL/6-Mc1re/e-HGF mice produced no melanoma in response to UVR or spontaneously even though the HGF transgene and its receptor Met were expressed. Total melanin was less than in C57BL/6-Mc1r+/+-HGF mice, hyperpigmentation was not observed and there were few extra-follicular melanocytes. Thus, functional Mc1r was required for expression of the transgenic HGF phenotype. Heterozygous C57BL/6-Mc1re/+-HGF mice were black and hyperpigmented and, although extra-follicular melanocytes and skin melanin content were similar to C57BL/6-Mc1r+/+-HGF animals, they developed UV-induced and spontaneous melanomas with significantly less efficiency by all criteria. Thus, heterozygosity for Mc1r was sufficient to restore the transgenic HGF phenotype but insufficient to fully restore melanoma. We conclude that a previously unsuspected melanin-independent interaction between Mc1r and Met signaling pathways is required for HGF-dependent melanoma and postulate that this pathway is involved in human melanoma