Clinical and molecular characteristics of Jordanian oropharyngeal cancer patients according to P16 expression: a retrospective study and a report of a novel biomarker.

The purpose of this study was to assess the clinicopathological features of oropharyngeal cancer patients in Jordan based on their HPV status. Sixty-nine biopsies from two hospitals were included. Tissue microarrays were prepared from formalin-fixed paraffin-embedded (FFPE) specimens and stained with antibodies for CDKN2A/P16, EGFR, PI3K, PTEN, AKT, pS473AKT, PS2mTOR, and TIMAP. The cohort was divided according to P16 expression. Chi-square test and survival analyses were employed to evaluate the variations among the study variables and determine the prognostic factors, respectively. P16 expression was found in 55.1% of patients; however, there was no significant association between P16 expression and the patients' clinicopathological features. The Kaplan-Meier test revealed that smoking in P16-positive group and younger age (< 58 years) negatively impacted disease-free survival (DFS) (P = 0.04 and P = 0.003, respectively). Multivariate Cox regression test indicated that smoking, age, PI3K, and AKT were negative predictors of DFS (P = 0.021, P = 0.002, P = 0.021, and P = 0.009, respectively), while TIMAP was a positive predictor (P = 0.045). Elevated P16 expression is found in more than half of the patients' specimens. DFS is negatively affected by younger age and the combined effect of smoking and P16 overexpression. TIMAP is overexpressed in P16-positive oropharyngeal cancer, and it is a favorable predictor of DFS.

Elevated interleukin 31 serum levels in hemodialysis patients are associated with uremic pruritus.

INTRODUCTION: Uremic pruritus is a multifactorial devastating complication of renal failure, which has a significant negative impact on patients' quality of life including medical, psychological, as well as social aspects. It is also associated with an increased mortality in dialysis patients. METHODS: A cross sectional study evaluating the traditional risk factors for uremic pruritus (UP) - using pruritus grading system (PGS) and visual analogue scale (VAS) - as well as measuring the serum levels of different inflammatory cytokines (ILs 13, 31 and 33) in chronic hemodialysis and healthy controls, in a tertiary referral hospital. RESULTS: 65 hemodialysis (HD) patients and 49 heathy controls were enrolled in the study. The mean age for the HD patients was 43.4 years (SD ± 21.3), and 31.5 years (SD ± 11.1) for the control group. The most common cause for End Stage Renal Disease (ESRD) was diabetes mellitus (DM) 27.7%. The mean PGS score in HD patients was 5.92 (SD ± 2.9); 50% had mild itch, 43.8% moderate itch and 6.2% had severe itch. The mean serum levels for IL-13 was 8674.3 pg/ml (SD ± 4353.9), serum levels of IL-31 were 150.7 pg/ml (SD ± 178.2) and for IL-33 it was 42850.5 pg/ml (SD ± 11370.7) in hemodialysis patients; in comparison to serum levels of 7913.4 pg/ml (SD ± 3454.1), 67.1 pg/ml (SD ± 71.9) and 44875.9 pg/ml (SD ± 12114.6), respectively in the control group. IL-31 level was significantly higher in HD patients than in the control group (P = 0.0001), while the difference in the levels of IL-13 and IL-33 between the two groups were not statistically significant (P = 0.41 and 0.18, respectively). IL-13 had a statistically significant relationship with the itch score (P = 0.014) and the severity of itch (P = 0.03), while IL-31 and IL-33 were not statistically significant. CONCLUSION: UP is a complex and multifactorial problem. In patients with UP the high levels of IL-31 indicates a possible role in pathogenesis. IL-13 serum level on the other hand may be related to the severity of itch in these patients. Optimizing dialysis and targeting these cytokines may provide a potential therapeutic option especially in refractory UP. Further studies addressing these cytokines and their levels in response to various treatments may provide additional information on UP.

Metallothionein isoforms as double agents - Their roles in carcinogenesis, cancer progression and chemoresistance.

Metallothioneins (MTs) are small cysteine-rich intracellular proteins with four major isoforms identified in mammals, designated MT-1 through MT-4. The best known biological functions of MTs are their ability to bind and sequester metal ions as well as their active role in redox homeostasis. Despite these protective roles, numerous studies have demonstrated that changes in MT expression could be associated with the process of carcinogenesis and participation in cell differentiation, proliferation, migration, and angiogenesis. Hence, MTs have the role of double agents, i.e., working with and against cancer. In view of their rich biochemical properties, it is not surprising that MTs participate in the emergence of chemoresistance in tumor cells. Many studies have demonstrated that MT overexpression is involved in the acquisition of resistance to anticancer drugs including cisplatin, anthracyclines, tyrosine kinase inhibitors and mitomycin. The evidence is gradually increasing for a cellular switch in MT functions, showing that they indeed have two faces: protector and saboteur. Initially, MTs display anti-oncogenic and protective roles; however, once the oncogenic process was launched, MTs are utilized by cancer cells for progression, survival, and contribution to chemoresistance. The duality of MTs can serve as a potential prognostic/diagnostic biomarker and can therefore pave the way towards the development of new cancer treatment strategies. Herein, we review and discuss MTs as tumor disease markers and describe their role in chemoresistance to distinct anticancer drugs.

Homologous G776G Variant of Transcobalamin-II Gene is Linked to Vitamin B12 Deficiency.

Vitamin B12 (Cobalamin) deficiency, due to improper internalization of cobalamin, is a metabolic disorder prevalent in impoverished and elderly populations and is associated with megaloblastic anemia and dementia. It has been suggested that mutations in transcobalamin II (TCN2) or gastric intrinsic factor (GIF) proteins can alter their binding efficiency to cobalamin or reduce the ability of their receptors to internalize them. In this case-control study, the correlation between vitamin B12 deficiency and alternative alleles of TCN2 and GIF was investigated in a Jordanian population. One hundred individuals with vitamin B12 deficiency (B12 < 200 mg/mL) were enrolled in our study to evaluate the TCN2 and GIF polymorphisms. The control group (B12 > 200 mg/mL) included 100 individuals. Our results indicated a significant association between the homologous variant of the TCN2 gene (G776G) and vitamin B12 deficiency, and an intermediate phenotype in heterozygous individuals (p < 0.001, OR = 5.6, 95% CI = 2.95 to 10.63). The GIF gene, however, showed no correlation between the A68G variant and vitamin B12 deficiency (p = 0.2). This study expounds the association of TCN2 polymorphism with cobalamin levels in a Jordanian population and highlights the necessity of further studies to elucidate the molecular basis and impact of TCN2 and GIF genes polymorphisms on vitamin B12 deficiency and associated disorders.

Pregnancy and Smoothelin-like Protein 1 (SMTNL1) Deletion Promote the Switching of Skeletal Muscle to a Glycolytic Phenotype in Human and Mice.

Pregnancy promotes physiological adaptations throughout the body, mediated by the female sex hormones progesterone and estrogen. Changes in the metabolic properties of skeletal muscle enable the female body to cope with the physiological challenges of pregnancy and may also be linked to the development of insulin resistance. We conducted global microarray, proteomic, and metabolic analyses to study the role of the progesterone receptor and its transcriptional regulator, smoothelin-like protein 1 (SMTNL1) in the adaptation of skeletal muscle to pregnancy. We demonstrate that pregnancy promotes fiber-type changes from an oxidative to glycolytic isoform in skeletal muscle. This phenomenon is regulated through an interaction between SMTNL1 and progesterone receptor, which alters the expression of contractile and metabolic proteins. smtnl1(-/-) mice are metabolically less efficient and show impaired glucose tolerance. Pregnancy antagonizes these effects by inducing metabolic activity and increasing glucose tolerance. Our results suggest that SMTNL1 has a role in mediating the actions of steroid hormones to promote fiber switching in skeletal muscle during pregnancy. Our findings also bear on the management of gestational diabetes that develops as a complication of pregnancy in ~4% of women.

Targeting Borrelia burgdorferi HtpG with a berserker molecule, a strategy for anti-microbial development.

Conventional antimicrobial discovery relies on targeting essential enzymes in pathogenic organisms, contributing to a paucity of new antibiotics to address resistant strains. Here, by targeting a non-essential enzyme, Borrelia burgdorferi HtpG, to deliver lethal payloads, we expand what can be considered druggable within any pathogen. We synthesized HS-291, an HtpG inhibitor tethered to the photoactive toxin verteporfin. Reactive oxygen species, generated by light, enables HS-291 to sterilize Borrelia cultures by causing oxidation of HtpG, and a discrete subset of proteins in proximity to the chaperone. This caused irreversible nucleoid collapse and membrane blebbing. Tethering verteporfin to the HtpG inhibitor was essential, since free verteporfin was not retained by Borrelia in contrast to HS-291. For this reason, we liken HS-291 to a berserker, wreaking havoc upon the pathogen's biology once selectively absorbed and activated. This strategy expands the druggable pathogenic genome and offsets antibiotic resistance by targeting non-essential proteins.

Smoothelin-like 1 protein is a bifunctional regulator of the progesterone receptor during pregnancy.

During pregnancy, uterine smooth muscle (USM) coordinately adapts its contractile phenotype in order to accommodate the developing fetus and then prepare for delivery. Herein we show that SMTNL1 plays a major role in pregnancy to promote adaptive responses in USM and that this process is specifically mediated through interactions of SMTNL1 with the steroid hormone receptor PR-B. In vitro and in vivo SMTNL1 selectively binds PR and not other steroid hormone receptors. The physiological relationship between the two proteins was also established in global gene expression and transcriptional reporter studies in pregnant smtnl1(-/-) mice and by RNA interference in progesterone-sensitive cell lines. We show that the contraction-associated and progestin-sensitive genes (oxytocin receptor, connexin 43, and cyclooxygenase-2) and prolactins are down-regulated in pregnant smtnl1(-/-) mice. We suggest that SMTNL1 is a bifunctional co-regulator of PR-B signaling and thus provides a molecular mechanism whereby PR-B is targeted to alter gene expression patterns within USM cells to coordinately promote alterations in USM function during pregnancy.

A highly selective Hsp90 affinity chromatography resin with a cleavable linker.

Over 200 proteins have been identified that interact with the protein chaperone Hsp90, a recognized therapeutic target thought to participate in non-oncogene addiction in a variety of human cancers. However, defining Hsp90 clients is challenging because interactions between Hsp90 and its physiologically relevant targets involve low affinity binding and are thought to be transient. Using a chemo-proteomic strategy, we have developed a novel orthogonally cleavable Hsp90 affinity resin that allows purification of the native protein and is quite selective for Hsp90 over its immediate family members, GRP94 and TRAP 1. We show that the resin can be used under low stringency conditions for the rapid, unambiguous capture of native Hsp90 in complex with a native client. We also show that the choice of linker used to tether the ligand to the insoluble support can have a dramatic effect on the selectivity of the affinity media.

Pharmacogenetic Study of the Dihydropyridine Dehydrogenase Gene in Jordanian Patients with Colorectal Cancer.

INTRODUCTION: Several studies have shown an association between 5-fluorouracil toxicity and variations in the dihydropyrimidine dehydrogenase (DPYD) gene. OBJECTIVES: This cross-sectional study aims to elucidate the association between genetic variations in the DPYD gene and 5-fluorouracil toxicity among Jordanians with colorectal cancer (CRC). METHODS: 80 CRC Patients were recruited to screen for mutations in the DPYD  gene using the Sanger sequencing technique. Sequencing results were analyzed using Mutation Surveyor software, and mutational effects were predicted by the Mutation Tester bioinformatics tool. RESULTS: Three reported variants (c.85T>C, c.1740+40A>G, c.1740+39C>T) and one novel (g.97515583_97515584insA) variant were identified in this study. Results showed a significant association between these variants and toxicity to 5-Fluorouracil with P-values 0.002, 0.005, 0.019, 0.017, respectively. However, there was no significant association between variants and cancer free survival. CONCLUSION: The present study identified several variants in the DPYD gene among Jordanians with colorectal cancer, which are associated with toxicity to 5-Fluorouracil treatment.

Smoothelin-like 1 protein regulates myosin phosphatase-targeting subunit 1 expression during sexual development and pregnancy.

Pregnancy coordinately alters the contractile properties of both vascular and uterine smooth muscles reducing systemic blood pressure and maintaining uterine relaxation. The precise molecular mechanisms underlying these pregnancy-induced adaptations have yet to be fully defined but are likely to involve changes in the expression of proteins regulating myosin phosphorylation. Here we show that smoothelin like protein 1 (SMTNL1) is a key factor governing sexual development and pregnancy induced adaptations in smooth and striated muscle. A primary target gene of SMTNL1 in these muscles is myosin phosphatase-targeting subunit 1 (MYPT1). Deletion of SMTNL1 increases expression of MYPT1 30-40-fold in neonates and during development expression of both SMTNL1 and MYPT1 increases over 20-fold. Pregnancy also regulates SMTNL1 and MYPT1 expression, and deletion SMTNL1 greatly exaggerates expression of MYPT1 in vascular smooth muscle, producing a profound reduction in force development in response to phenylephrine as well as sensitizing the muscle to acetylcholine. We also show that MYPT1 is expressed in Type2a muscle fibers in mice and humans and its expression is regulated during pregnancy, suggesting unrecognized roles in mediating skeletal muscle plasticity in both species. Our findings define a new conserved pathway in which sexual development and pregnancy mediate smooth and striated muscle adaptations through SMTNL1 and MYPT1.

TIMAP Upregulation Correlates Negatively with Survival in HER2- Negative Subtypes of Breast Cancer.

OBJECTIVE: TIMAP expression is regulated by transforming growth factor beta 1 (TGFß1); known for its role in breast cancer development and metastasis. Nevertheless, data on TIMAP protein expression and its association with breast cancer development are lacking. In this study, we aimed to investigate the variation in TIMAP protein expression in breast cancer tissue and its correlation with various clinicopathological characteristics of breast cancer patients and overall survival rate. METHODS: A total of 159 paraffin-embedded tissue blocks from women diagnosed with four breast cancer subtypes (49 HER2-only, 33 Luminal A, 39 Luminal B, and 38 triple negative) were used to construct tissue microarray (TMA), followed by TIMAP immunohistochemistry (IHC). TIMAP expression was scored by two pathologists and categorized as weak (1-33% expression), moderate (34-66%), and strong (67-100%). Chi-square test and Kaplan Meier survival test were performed to determine the association between TIMAP expression and clinicopathological features and overall survival rate, respectively. RESULTS: TIMAP protein was strongly expressed in 46 (93.9%) HER2-only, 32 (97%) luminal A, 37 (94.9%) luminal B, and 29 (76.3%) triple negative. TIMAP expression negatively associated with ER/PR expression (P=0.03), and it negatively impacted the overall survival in HER2 negative group (P=0.02). CONCLUSION: Our findings suggest that TIMAP protein expression is upregulated in all breast cancer subtypes. However, its prognostic role is exclusively observed in HER2- negative group, suggesting a potential of targeting TIMAP in future therapeutic strategies in this group.

Post-acne hyperpigmentation: Evaluation of risk factors and the use of artificial neural network as a predictive classifier.

Acne is common among young individuals. People with dark skin have a higher risk for developing pigmentary complications. Inflammation is an important factor in post-acne hyperpigmentation however other factors are also involved in developing this complication however these factors are not well studied. The aim of this study is to identify risk factors involved in post-acne hyperpigmentation. Clinical data related to acne, acne- related hyperpigmentation were collected. Data was analyzed for risk factors associated with acne pigmentation. Artificial neural network was used as predictive disease classifier for the outcome of pigmentation. Majority of patients in this study (339 patients) had dark skin phototypes (3 and 4). Post- acne hyperpigmentation was seen in more than 80% of patients. Females, darker skin color, severe acne, facial sites, and excessive sunlight exposure, squeezing or scratching lesions are important risk factors for post-acne hyperpigmentation. Post-acne hyperpigmentation is multifactorial. Several factors implicated in PAH are modifiable by adequate patient education (lesion trauma, excessive sunlight exposure). The use of ANN was helpful in predicting appearance of post-acne hyperpigmentation based on identified risk factors.

Hereditary multiple osteochondromas in Jordanian patients: Mutational and immunohistochemical analysis of EXT1 and EXT2 genes.

The aim of the present study was to investigate the molecular characteristics of hereditary multiple osteochondromas (HMO) in a subset of Jordanian patients with a focus on the genetic variants of exostosin (EXT1)/(EXT2) and their protein expression. Patients with HMO and their family members were included. Recorded clinical characteristics included age, sex, tumors number and location, joint deformities and associated functional limitations. Mutational analysis of EXT1 and EXT2 exonic regions was performed. Immunohistochemical staining for EXT1 and EXT2 was performed manually using two different commercially available rabbit anti-human EXT1 and EXT2 antibodies. A total of 16 patients with HMO from nine unrelated families were included, with a mean age of 13.9 years. A total of 75% (12/16) of the patients were male and (69%) (11/16) had a mild disease (class I). EXT mutation analysis revealed only EXT1 gene mutations in 13 patients. Seven variants were detected, among which three were novel: c.1019G>A, p. (Arg340His), c.962+1G>A and c.1469del, p. (Leu490Argfs*9). Of the 16 patients, 3 did not harbor any mutations for either EXT1 or EXT2. Immunohistochemical examination revealed decreased expression of EXT1 protein in all patients with EXT1 mutation. Surprisingly, EXT2 protein was not detected in these patients, although none had EXT2 mutations. The majority of Jordanian patients with HMO, who may represent an ethnic group that is infrequently investigated, were males and had a mild clinical disease course; whereas most patients with EXT1 gene mutations were not necessarily associated with a severe clinical disease course. The role of EXT2 gene remains a subject of debate, since patients with EXT1 mutations alone did not express the non-mutated EXT2 gene.

LAT1 (SLC7A5) Overexpression in Negative Her2 Group of Breast Cancer: A Potential Therapy Target.

OBJECTIVE: HER2 negative carcinomas of the breast pose a challenge for treatment due to redundancies in potential drug targets and poor patient outcomes. Our aim was to investigate the role of L-type amino acid transporter - LAT1 as a potential prognosticator and a drug target. METHODS: In this retrospective work, we have studied the expression of LAT1 in 145 breast cancer tissues via immunohistochemistry. Overall survival analysis was used to evaluate patient outcome in various groups of our cohort. RESULTS: Positive LAT1 expression was found in 27 (84.4%) luminal A subtype, 27 (64.3%) luminal B/triple positive subtype, 29 (82.9%) triple negative subtype, and 24 (66.7%) HER2-only positive subtype (p=0.1). Interestingly, negative correlation was found between LAT1 and HER2; where positive expression of LAT1 was found in 56 (83.6%) cases in negative HER2 group and 51 (65.4%) cases from positive HER2 group (p=0.01). Unfortunately, we were unable to report significant survival differences when LAT1 expression was studied in the negative HER2 group. Nevertheless, five incidents of mortality (out of 55) were reported in LAT1+/HER2- group compared to none in the LAT1-/HER2- group (N=11). CONCLUSION: Our findings of overexpression of LAT1 in negative HER2 group suggest a role of this protein as prognosticator and drug target in a challenging therapeutic cohort.
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IL-33/13 Axis and IL-4/31 Axis Play Distinct Roles in Inflammatory Process and Itch in Psoriasis and Atopic Dermatitis.

BACKGROUND: Pruritus is the most common symptom in patients with skin disease. Psoriasis and atopic dermatitis are clinically distinct inflammatory diseases. Interleukins are cytokines which play key roles in inflammatory signaling pathways. MATERIALS AND METHODS: Cross-sectional study was conducted among patients with psoriasis and atopic dermatitis: 59 psoriatic patients, 56 AD patients, and 49 matched healthy controls. Interleukins 4, 13, 31, 33 serum levels were assayed by ELISA and results were compared using SPSS. Itch severity and disease severity were measured and correlation with interleukin levels was determined using SPSS. RESULTS: The serum levels of IL-4, -13, -31, -33 were elevated in atopic dermatitis patients compared to controls. Itch and disease severity were not correlated with elevated serum levels of these interleukins. In psoriasis, the levels of IL-4 and -31 were elevated compared to controls, whereas the levels of IL-13 and -33 were lower than controls. The levels of measured interleukins in psoriasis did not correlate with itch and disease severity. CONCLUSION: IL-31 is the key mediator for pruritus in both AD and Ps patients. IL-4/31 axis and IL-33/13 axis play distinct roles in the pathogenesis of Atopic dermatitis and Psoriasis. Interleukin serum levels were not correlated with itch and disease severity in both conditions.

Awareness about proper use of sunscreen in people of color: A Jordanian-based survey.

INTRODUCTION: The use of sunscreen is an important preventive measure against skin cancer and treatment for other skin conditions. There is evidence pointing to lack awareness and misconceptions regarding use of Sunscreen. This is especially evident in populations with skin of color (POC). METHODS: This is a cross-sectional study of 2000 individuals. A structured questionnaire was designed to collect data on general knowledge and use of sunscreen as well as reasons for stopping use of sunscreen. RESULTS: The results of this study indicate a clear deficiency in the use and knowledge about sunscreen among Jordanians. Females are using sunscreen more than males. However, the use of sunscreen is inadequate in many aspects including timing of application, frequency of use, and amount used among other things. There is an obvious lack of knowledge about sunscreen as shown by lack of awareness about benefits of use in various times of the year, use in children, use for all skin types, and several misconceptions among other knowledge gaps. Main reasons for stopping sunscreen include side effects, cost, and being not suitable for skin. Awareness about sunscreen can be improved by proper counseling by healthcare professionals and utilization of various media platforms. CONCLUSIONS: The use of sunscreen is inadequate in this population of color (POC). Lack of proper counseling, failure to read use instructions can contibute to inadequate use of sunscreen. Risks and benefits of sunscreen should be explained by medical professionals. The media should be more utilized to disseminate such knowledge.

Heat shock protein 90-targeted photodynamic therapy enables treatment of subcutaneous and visceral tumors.

Photodynamic therapy (PDT) ablates malignancies by applying focused near-infrared (nIR) light onto a lesion of interest after systemic administration of a photosensitizer (PS); however, the accumulation of existing PS is not tumor-exclusive. We developed a tumor-localizing strategy for PDT, exploiting the high expression of heat shock protein 90 (Hsp90) in cancer cells to retain high concentrations of PS by tethering a small molecule Hsp90 inhibitor to a PS (verteporfin, VP) to create an Hsp90-targeted PS (HS201). HS201 accumulates to a greater extent than VP in breast cancer cells both in vitro and in vivo, resulting in increased treatment efficacy of HS201-PDT in various human breast cancer xenografts regardless of molecular and clinical subtypes. The therapeutic index achieved with Hsp90-targeted PDT would permit treatment not only of localized tumors, but also more diffusely infiltrating processes such as inflammatory breast cancer.

Genetics of Female Infertility: Molecular Study of Newborn Ovary Homeobox Gene in Poor Ovarian Responders.

BACKGROUND: Newborn ovary homeobox (NOBOX) gene plays a critical role in the transcriptional regulation of oocyte-specific genes. Previous studies have demonstrated a pathogenic effect of NOBOX variants on premature ovarian insufficiency (POI) patients. Poor ovarian response (POR) is a risk factor for POI. Therefore, genetic variants in the NOBOX gene may also be studied as risk factors for POR development. AIMS: The aim of the study is to investigate the association between seven known NOBOX single-nucleotide polymorphisms (SNPs) and POR in Jordanian females. SETTINGS AND DESIGN: This was a case-control study of 60 females with POR for controlled ovarian hyperstimulation and 59 healthy females with no history of reproductive problems. Blood samples were collected from the participants and seven SNPs of NOBOX gene were screened. SUBJECTS AND METHODS: DNA was extracted from blood samples. Polymerase chain reaction with primers specific for seven known SNPs in NOBOX gene was used to amplify the specified region within the gene followed by Sanger sequencing. RESULTS: The seven SNPs investigated in this study, namely, rs77587352 (c.271G>T, p. Gly91Trp), rs7800847 (c.349C>T, p. Arg117Trp), rs193303102 (c.907C>T, p. Arg303X), rs193303103 (c.1025G>C, p. Ser342Thr), rs193303104 (c.1048G>T, p. Val350Leu), rs201947677 (c.1064G>A, p. Arg355His), and rs146227301 (c.1856C>T, p. Pro619Leu), only represent the wild-type allele in both females with POR and healthy participants. CONCLUSIONS: The results show that only monomorphic genotype of the NOBOX variants was found in Jordanian females studied.

LPS protects macrophages from AIF-independent parthanatos by downregulation of PARP1 expression, induction of SOD2 expression, and a metabolic shift to aerobic glycolysis.

In inflamed tissues or during ischemia-reperfusion episodes, activated macrophages produce large amounts of reactive species and are, thus, exposed to the damaging effects of reactive species. Here, our goal was to investigate the mechanism whereby activated macrophages protect themselves from oxidant stress-induced cell death. Hydrogen peroxide-treated mouse bone marrow-derived macrophages (BMDM) and THP-1 human monocyte-derived cells were chosen as models. We found a gradual development of resistance: first in monocyte-to-macrophage differentiation, and subsequently after lipopolysaccharide (LPS) exposure. Investigating the mechanism of the latter, we found that exposure to intense hydrogen peroxide stress causes poly(ADP-ribose) polymerase-1 (PARP-1) dependent programmed necrotic cell death, also known as parthanatos, as indicated by the protected status of PARP-1 knockout BMDMs and the protective effect of the PARP inhibitor PJ-34. In hydrogen peroxide-treated macrophages, however, apoptosis inducing factor (AIF) proved dispensable for parthanatos; nuclear translocation of AIF was not observed. A key event in LPS-mediated protection against the hydrogen peroxide-induced AIF independent parthanatos was downregulation of PARP1 mRNA and protein. The importance of this event was confirmed by overexpression of PARP1 in THP1 cells using a viral promoter, which lead to stable PARP1 levels even after LPS treatment and unresponsiveness to LPS-induced cytoprotection. In BMDMs, LPS-induced PARP1 suppression lead to prevention of NAD+ depletion. Moreover, LPS also induced expression of antioxidant proteins (superoxide dismutase-2, thioredoxin reductase 1 and peroxiredoxin) and triggered a metabolic shift to aerobic glycolysis, also known as the Warburg effect. In summary, we provide evidence that in macrophages intense hydrogen peroxide stress causes AIF-independent parthanatos from which LPS provides protection. The mechanism of LPS-mediated cytoprotection involves downregulation of PARP1, spared NAD+ and ATP pools, upregulation of antioxidant proteins, and a metabolic shift from mitochondrial respiration to aerobic glycolysis.

Evaluation of Patched-1 Protein Expression Level in Low Risk and High Risk Basal Cell Carcinoma Subtypes.

Objective: Basal cell carcinoma (BCC) is the most common malignancy in humans and represents a growing public health care problem. The major etiological factors contributing to BCC development are exposure to ultraviolet radiation and genetic alterations. BCC is primarily caused by dysregulation of sonic Hedgehog (HH) signaling pathway in basal cells of the skin. BCC can be classified into low risk non-aggressive and high risk aggressive subtypes. BCC subtypes differentiation is essential for prognosis and for better disease management and treatment strategies. The aim of this study was to assess the correlation between PTCH1 protein expression level and the aggressiveness of BCC histopathology. Methods: Archival paraffin embedded blocks containing BCC were retrieved from a cohort of 101 patients. Immunohistochemistry staining was performed to assess the expression level of PTCH1 which is a key component of Hedgehog pathway. Results: 101 paraffin embedded samples were evaluated and classified as high risk and low risk BCC subtypes by histopathological finding. High risk BCC subtypes were found in 40 samples (39.6%) and low risk subtypes were identified in 61 samples (60.4%). Nodular was the most frequent subtype which was found in (56/ 101), followed by infiltrative (22/101) and micronodular (14/ 101) subtypes. Positive PTCH1 expression was found highest in nodular subtypes (46.5%). Conclusion: In this study, the correlation between low risk or high risk BCC subtypes and PTCH1 expression level was not statistically significant (p>0.05), but the frequency of positive PTCH1 expression was found to be higher in low risk subtypes than high risk BCC subtypes.