Emodin inhibits HDAC6 mediated NLRP3 signaling and relieves chronic inflammatory pain in mice.

Chronic pain reduces the quality of life and ability to function of individuals suffering from it, making it a common public health problem. Neuroinflammation which is mediated by the Nod-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome activation in the spinal cord participates and modulates chronic pain. A chronic inflammatory pain mouse model was created in the current study by intraplantar injection of complete Freund's adjuvant (CFA) into C57BL/6J left foot of mice. Following CFA injection, the mice had enhanced pain sensitivities, decreased motor function, increased spinal inflammation and activated spinal astrocytes. Emodin (10 mg/kg) was administered intraperitoneally into the mice for 3 days. As a result, there were fewer spontaneous flinches, higher mechanical threshold values and greater latency to fall. Additionally, in the spinal cord, emodin administration reduced leukocyte infiltration level, downregulated protein level of IL-1ß, lowered histone deacetylase (HDAC)6 and NLRP3 inflammasome activity and suppressed astrocytic activation. Emodin also binds to HDAC6 via four electrovalent bonds. In summary, emodin treatment blocked the HDAC6/NLRP3 inflammasome signaling, suppresses spinal inflammation and alleviates chronic inflammatory pain.

Synthesis of Imidazo[1,2-a]pyridine-Fused 1,3-Benzodiazepine Derivatives with Anticancer Activity via a One-Pot Cascade GBB-3CR/Pd(II)-Catalyzed Azide-Isocyanide Coupling/Cyclization Process.

A new one-pot synthesis of imidazo[1,2-a]pyridine-fused 1,3-benzodiazepine derivatives via a sequential GBB-3CR/Pd(II)-catalyzed azide-isocyanide coupling/cyclization process was developed. The Groebke-Blackburn-Bienaymé three-component reactions (GBB-3CR) of 2-aminopyridine, 2-azidobenzaldehydes, and isocyanides in the presence of a catalytic amount of p-toluenesulfonic acid gave azide intermediates without separation. The reaction was followed by using another molecule of isocyanides to produce imidazo[1,2-a]pyridine-fused 1,3-benzodiazepine derivatives in good yields by the Pd(II)-catalyzed azide-isocyanide coupling/cyclization reaction. The synthetic approach produces novel nitrogen-fused polycyclic heterocycles under mild reaction conditions. The preliminary biological evaluation demonstrated that compound 6a inhibited glioma cells efficiently, suggesting potentially broad applications of the approach for synthesis and medicinal chemistry.

Alleviating effect of lycorine on CFA­induced arthritic pain via inhibition of spinal inflammation and oxidative stress.

Chronic pain is the primary symptom of osteoarthritis affecting a patient's quality of life. Neuroinflammation and oxidative stress in the spinal cord contribute to arthritic pain and represent ideal targets for pain management. In the present study, a model of arthritis was established by intra-articular injection of complete Freund's adjuvant (CFA) into the left knee joint in mice. After CFA inducement, knee width and pain hypersensitivity in the mice were increased, motor disability was impaired, spinal inflammatory reaction was induced, spinal astrocytes were activated, antioxidant responses were decreased, and glycogen synthase kinase 3ß (GSK-3ß) activity was inhibited. To explore the potential therapeutic options for arthritic pain, lycorine was intraperitoneally injected for 3 days in the CFA mice. Lycorine treatment significantly reduced mechanical pain sensitivity, suppressed spontaneous pain, and recovered motor coordination in the CFA-induced mice. Additionally, in the spinal cord, lycorine treatment decreased the inflammatory score, reduced NOD-like receptor protein 3 inflammasome (NLRP3) activity and IL-1ß expression, suppressed astrocytic activation, downregulated NF-κB levels, increased nuclear factor erythroid 2-related factor 2 expression and superoxide dismutase activity. Furthermore, lycorine was shown to bind to GSK-3ß through three electrovalent bonds, to inhibit GSK-3ß activity. In summary, lycorine treatment inhibited GSK-3ß activity, suppressed NLRP3 inflammasome activation, increased the antioxidant response, reduced spinal inflammation, and relieved arthritic pain.

GSK-3ß inhibition alleviates arthritis pain via reducing spinal mitochondrial reactive oxygen species level and inflammation.

Pain is the main symptom of osteoarthritis, which severely reduces the patients' quality of life. Stimulated neuroinflammation and elevated mitochondrial oxidative stress are associated arthritis pain. In the present study, arthritis model was established by intra-articular injection of complete Freund's adjuvant (CFA) on mice. Knee swelling, pain hypersensitivity and motor disability were observed in CFA-induced mice. In spinal cord, neuroinflammation was triggered and presented as severe infiltration of inflammatory cells and up-regulated expressions of glial fibrillary acidic protein (GFAP), nuclear factor-kappaB (NF-κB), PYD domains-containing protein 3 (NLRP3), cysteinyl aspartate specific proteinase (caspase-1) and interleukin-1 beta (IL-1ß). Mitochondrial function was disrupted and characterized as elevated expressions of B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax), dihydroorotate dehydrogenase (DHODH) and cytochrome C (Cyto C), and reduced expressions of Bcl-2 and Mn-superoxide dismutase (Mn-SOD) activity. Meanwhile, as a potential target for pain management, glycogen synthase kinase-3 beta (GSK-3ß) activity was up-regulated in CFA induced mice. To explore potential therapeutic options for arthritis pain, GSK-3ß inhibitor TDZD-8 was intraperitoneally injected for three days on CFA mice. Animal behavioral tests found that TDZD-8 treatment elevated mechanical pain sensitivity, suppressed spontaneous pain and recovered motor coordination. Morphological and protein expression analysis indicated that TDZD-8 treatment decreased spinal inflammation score and inflammatory related protein levels, recovered mitochondrial related protein levels, and increased Mn-SOD activity. In summary, TDZD-8 treatment inhibits GSK-3ß activity, reduces mitochondrial mediated oxidative stress, suppresses spinal inflammasome response, and alleviates arthritis pain.

Emodin suppresses oxaliplatin-induced neuropathic pain by inhibiting COX2/NF-κB mediated spinal inflammation.

Oxaliplatin (OXA) is a common chemotherapy drug for colorectal, gastric, and pancreatic cancers. The anticancer effect of OXA is often accompanied by neurotoxicity and acute and chronic neuropathy. The symptoms present as paresthesia and pain which adversely affect patients' quality of life. Herein, five consecutive intraperitoneal injections of OXA at a dose of 4 mg/kg were used to mimic chemotherapy. OXA administration induced mechanical allodynia, activated spinal astrocytes, and increased inflammatory response. To develop an effective therapeutic measure for OXA-induced neuropathic pain, emodin was intrathecally injected into OXA rats. Emodin developed an analgesic effect, as demonstrated by a significant increase in the paw withdrawal threshold of OXA rats. Moreover, emodin treatment reduced the pro-inflammatory cytokines (tumor necrosis factor-α and interleukin-1ß) which upregulated in OXA rats. Furthermore, autodock data showed four hydrogen bonds were formed between emodin and cyclooxygenase-2 (COX2), and emodin treatment decreased COX2 expression in OXA rats. Cell research further proved that emodin suppressed nuclear factor κB (NF-κB)-mediated inflammatory signal and reactive oxygen species level. Taken together, emodin reduced spinal COX2/NF-κB mediated inflammatory signal and oxidative stress in the spinal cord of OXA rats which consequently relieved OXA-induced neuropathic pain.

Emodin alleviates arthritis pain through reducing spinal inflammation and oxidative stress.

Chronic pain is the predominant problem for rheumatoid arthritis patients, and negatively affects quality of life. Arthritis pain management remains largely inadequate, and developing new treatment strategies are urgently needed. Spinal inflammation and oxidative stress contribute to arthritis pain and represent ideal targets for the treatment of arthritis pain. In the present study, collagen-induced arthritis (CIA) mouse model was established by intradermally injection of type II collagen (CII) in complete Freund's adjuvant (CFA) solution, and exhibited as paw and ankle swelling, pain hypersensitivity and motor disability. In spinal cord, CIA inducement triggered spinal inflammatory reaction presenting with inflammatory cells infiltration, increased Interleukin-1ß (IL-1ß) expression, and up-regulated NOD-like receptor thermal protein domain associated protein 3 (NLRP3) and cleaved caspase-1 levels, elevated spinal oxidative level presenting as decreased nuclear factor E2-related factor 2 (Nrf2) expression and Superoxide dismutase (SOD) activity. To explore potential therapeutic options for arthritis pain, emodin was intraperitoneally injected for 3 days on CIA mice. Emodin treatment statistically elevated mechanical pain sensitivity, suppressed spontaneous pain, recovered motor coordination, decreased spinal inflammation score and IL-1ß expression, increased spinal Nrf2 expression and SOD activity. Further, AutoDock data showed that emodin bind to Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) through two electrovalent bonds. And emodin treatment increased the phosphorylated AMPK at threonine 172. In summary, emodin treatment activates AMPK, suppresses NLRP3 inflammasome response, elevates antioxidant response, inhibits spinal inflammatory reaction and alleviates arthritis pain.

2-Bromopalmitate decreases spinal inflammation and attenuates oxaliplatin-induced neuropathic pain via reducing Drp1-mediated mitochondrial dysfunction.

Oxaliplatin (OXA) is a third-generation platinum compound with clinical activity in multiple solid tumors. Due to the repetition of chemotherapy cycle, OXA-induced chronic neuropathy presenting as paresthesia and pain. This study explored the neuropathy of chemotherapy pain and investigated the analgesic effect of 2-bromopalmitate (2-BP) on the pain behavior of OXA-induced rats. The chemotherapy pain rat model was established by the five consecutive administration of OXA (intraperitoneal, 4 mg/kg). After the establishment of OXA-induced rats, the pain behavior test, inflammatory signal analysis and mitochondrial function measurement were conducted. OXA-induced rats exhibited mechanical allodynia and spinal inflammatory infiltration. Our fluorescence and western blot analysis revealed spinal astrocytes were activated in OXA rats with up-regulation of astrocytic markers. In addition, NOD-, LRR- and pyrin domain-containing 3 (NLRP3) inflammasome mediated inflammatory signal cascade was also activated. Inflammation was triggered by dysfunctional mitochondria which represented by increase in cyclooxygenase-2 (COX-2) level and manganese superoxide dismutase (Mn-SOD) activity. Intrathecally injection of 2-BP significantly attenuated dynamin-related protein 1 (Drp1) mediated mitochondrial fission, recovered mitochondrial function, suppressed NLRP3 inflammasome cascade, and consequently decreased mechanical pain sensitivity. For cell research, 2-BP treatment significantly reversed tumor necrosis factor-α (TNF-α) induced mitochondria membrane potential deficiency and high reactive oxygen species (ROS) level. These findings indicate 2-BP decreases spinal inflammation and relieves OXA-induced neuropathic pain via reducing Drp1-mediated mitochondrial dysfunction.

Resveratrol ameliorates oxaliplatin-induced neuropathic pain via anti-inflammatory effects in rats.

Oxaliplatin (OXA) is a common chemotherapy drug and exhibits clinical activity in several cancer types. Its anticancer clinical effect is frequently accompanied by neurotoxicity. The symptoms include paresthesia and pain, which adversely affect the quality of life of patients. In the present study, five consecutive intraperitoneal injections of 4 mg/kg OXA were used to mimic chemotherapy in rats. OXA administration induced mechanical allodynia, activated spinal astrocytes and triggered the inflammatory response. To explore potential therapeutic options for OXA-induced neuropathic pain, resveratrol (Res) was intrathecally injected into the spinal cord of OXA-treated rats. Paw withdrawal threshold values of OXA-treated rats were increased, indicating an antinociception effect of Res on OXA-induced pain. Additionally, Res treatment reduced the levels of glial fibrillary acidic protein, TNF-α, IL-1ß and NF-κB, which were upregulated in OXA-treated rats (compared with control). Furthermore, Auto Dock data showed that Res binds to cyclooxygenase-2 (COX-2) through six hydrogen bonds. Western blot analysis and reactive oxygen species (ROS) assays indicated that Res treatment decreased COX-2 expression and suppressed ROS production. In summary, intrathecal injection of Res reduced the spinal COX-2-mediated ROS generation and inflammatory reaction, suppressed astrocytic activation, and alleviated OXA-induced neuropathic pain.

Synthesis of 4-Tetrazolyl-Substituted 3,4-Dihydroquinazoline Derivatives with Anticancer Activity via a One-Pot Sequential Ugi-Azide/Palladium-Catalyzed Azide-Isocyanide Cross-Coupling/Cyclization Reaction.

A new one-pot preparation of 4-tetrazolyl-3,4-dihydroquinazolines has been reported. The Ugi-azide reactions of 2-azidobenzaldehydes, amines, trimethylsilyl azide, and isocyanides produced azide intermediates without separation, which were treated with isocyanides to give 4-tetrazolyl-3,4-dihydroquinazoline derivatives through a sequential Palladium-catalyzed azide-isocyanide cross-coupling/cyclization reaction in moderate to good yields. The biological evaluation demonstrated that compound 6c inhibited breast cancer cells well and displayed broad applications for synthesis and medicinal chemistry.

Glycogen synthase kinase-3ß inhibition decreases inflammation and relieves cancer induced bone pain via reducing Drp1-mediated mitochondrial damage.

Bone is the preferential site of metastasis for breast cancer. Invasion of cancer cells induces the destruction of bone tissue and damnification of peripheral nerves and consequently induced central sensitization which contributes to severe pain. Herein, cancer induced bone pain (CIBP) rats exhibited destruction of tibia, mechanical allodynia and spinal inflammation. Inflammatory response mainly mediated by astrocyte and microglia in central nervous system. Our immunofluorescence analysis revealed activation of spinal astrocytes and microglia in CIBP rats. Transmission electron microscopy (TEM) observations of mitochondrial outer membrane disruption and cristae damage in spinal mitochondria of CIBP rats. Proteomics analysis identified abnormal expression of proteins related to mitochondrial organization and function. Intrathecally, injection of GSK-3ß activity inhibitor TDZD-8 significantly attenuated Drp1-mediated mitochondrial fission and recovered mitochondrial function. Inhibition of GSK-3ß activity also suppressed NLRP3 inflammasome cascade and consequently decreased mechanical pain sensitivity of CIBP rats. For cell research, TDZD-8 treatment significantly reversed TNF-α induced mitochondrial membrane potential (MMP) deficiency and high mitochondrial reactive oxygen species level. Taken together, GSK-3ß inhibition by TDZD-8 decreases spinal inflammation and relieves cancer induced bone pain via reducing Drp1-mediated mitochondrial damage.

A SIRPα-Fc fusion protein enhances the antitumor effect of oncolytic adenovirus against ovarian cancer.

Oncolytic viruses armed with therapeutic transgenes of interest show great potential in cancer immunotherapy. Here, a novel oncolytic adenovirus carrying a signal regulatory protein-α (SIRPα)-IgG1 Fc fusion gene (termed SG635-SF) was constructed, which could block the CD47 'don't eat me' signal of cancer cells. A strong promoter sequence (CCAU) was chosen to control the expression of the SF fusion protein, and a 5/35 chimeric fiber was utilized to enhance the efficiency of infection. As a result, SG635-SF was found to specifically proliferate in hTERT-positive cancer cells and largely increased the abundance of the SF gene. The SF fusion protein was effectively detected, and CD47 was successfully blocked in SK-OV3 and HO8910 ovarian cancer cells expressing high levels of CD47. Although the ability to induce cell cycle arrest and cell death was comparable to that of the control empty SG635 oncolytic adenovirus in vitro, the antitumor effect of SG635-SF was significantly superior to that of SG635 in vivo. Furthermore, CD47 was largely blocked and macrophage infiltration distinctly increased in xenograft tissues of SK-OV3 cells but not in those of CD47-negative HepG2 cells, indicating that the enhanced antitumor effect of SG635-SF was CD47-dependent. Collectively, these findings highlight a potent antitumor effect of SG635-SF in the treatment of CD47-positive cancers.

No significant association between immunosuppression in solid organ transplantation and prostate cancer risk: a meta-analysis of cohort studies.

BACKGROUND: It is known that organ transplant recipients have a significantly higher risk for developing cancers, but the association between immunosuppression in organ transplantation and the risk for prostate cancer (PCa) remains unclear. We aimed to assess the evidence regarding the association of solid organ transplantation with PCa risk. METHODS: A literature search of the PubMed, Embase, and Web of Science databases was performed up to March 2019. Combined relative risks (RRs) and 95% confidence intervals (CIs) were calculated by using a fixed-effect or random-effect model. RESULTS: In total, 26 articles including 33 independent population-based cohort studies with 556,812 recipients and 2,438 PCa cases were identified and included in this meta-analysis. PCa risk in the solid organ transplant recipients did not increase compared with the general population (RR=1.04; 95% CI: 0.90-1.18). Independent analysis of different kinds of organ replacements further indicated immune inhibition in the transplantation of kidney, liver, heart, and lung, and was not associated with elevated PCa risk (RR=0.89; 95% CI: 0.83-0.95; RR=0.61, 95% CI: 0.21-1.02; RR=1.70, 95% CI: 0.88-2.52; RR=0.87, 95% CI: 0.57-1.16, respectively). CONCLUSIONS: This study demonstrated that immunosuppression in solid organ transplant recipients was not associated with higher PCa risk.

SIRT1 activation by SRT1720 attenuates bone cancer pain via preventing Drp1-mediated mitochondrial fission.

Bone cancer pain (BCP) is the pain induced by primary bone cancer or tumor metastasis. Increasing evidence and our previous studies have shown that mammalian silent information regulator 2 homolog (SIRT1) is involved in periphery sensitization and central sensitization of BCP, and the underlying mechanism of SIRT1 in bone cancer pain may provide clues for pain treatment. Dynamin-related protein 1 (Drp1) is an essential regulator for mitochondrial fission. In this research, BCP model rats were established by injecting MRMT-1 rat mammary gland carcinoma cells into the left tibia of female Sprague-Dawley rats and validated by tibia radiographs, histological examination and mechanical pain test. As a result BCP rats exhibited bone destruction and sensitivity mechanical pain. BCP increased inflammatory cells infiltration and apoptosis, reduced SIRT1 protein expression and phosphorylation, and elevated Drp1 expression in spinal cord. An agonist of SIRT1 named SRT1720 intrathecal treatment in BCP rats increased SIRT1 phosphorylation, reduced the up-regulated Drp1 expression, and reversed pain behavior. SRT1720 also regulated Bcl-2/BAX and cleaved caspase-3 expressions, and inhibited mitochondrial apoptosis in spinal cord of BCP rats. For in vitro research, SRT1720 treatment decreased Drp1 expression in a dose-dependent manner, blocked CCCP-induced mitochondrial membrane potential change, consequently reduced apoptosis and promoted proliferation. These data suggest that SIRT1 activation by SRT1720 attenuated bone cancer pain via preventing Drp1-mediated mitochondrial fission. Our results provide new targets for therapeutics of bone cancer pain.

Antitumor activity of EGFR-specific CAR T cells against non-small-cell lung cancer cells in vitro and in mice.

Effective control of non-small-cell lung cancer (NSCLC) remains clinically challenging, especially during advanced stages of the disease. This study developed an adoptive T-cell treatment through expression of a chimeric antigen receptor (CAR) to target human epidermal growth factor receptor (EGFR) in NSCLC. We optimized the non-viral piggyBac transposon system to engineer human T cells for the expression of EGFR-CAR, consisting of EGFR scFv, transmembrane domain, and intracellular 4-1BB-CD3ζ signaling domains. The modified CAR T cells exhibited expansion capability and anticancer efficacy in a time- and antigen-dependent manner in vitro as well as regression of EGFR-positive human lung cancer xenografts in vivo. EGFR-CAR T therapy is a promising strategy to improve the efficacy and potency of the adoptive immunotherapy in NSCLC. Moreover, EGFR-CAR T therapy could become a clinical application for NSCLC patients in the future.

11R-P53 and GM-CSF Expressing Oncolytic Adenovirus Target Cancer Stem Cells with Enhanced Synergistic Activity.

Targeting cancer stem cells with oncolytic virus (OV) holds great potential for thorough elimination of cancer cells. Based on our previous studies, we here established 11R-P53 and mGM-CSF carrying oncolytic adenovirus (OAV) SG655-mGMP and investigated its therapeutic effect on hepatocellular carcinoma stem cells Hep3B-C and teratoma stem cells ECCG5. Firstly, the augmenting effect of 11R in our construct was tested and confirmed by examining the expression of EGFP with Fluorescence and FCM assays after transfecting Hep3B-C and ECCG5 cells with OVA SG7605-EGFP and SG7605-11R-EGFP. Secondly, the expressions of 11R-P53 and GM-CSF in Hep3B-C and ECCG5 cells after transfection with OAV SG655-mGMP were detected by Western blot and Elisa assays, respectively. Thirdly, the enhanced growth inhibitory and augmented apoptosis inducing effects of OAV SG655-mGMP on Hep3B-C and ECCG5 cells were tested with FCM assays by comparing with the control, wild type 5 adenovirus, 11R-P53 carrying OVA in vitro. Lastly, the in vivo therapeutic effect of OAV SG655-mGMP toward ECCG5 cell-formed xenografts was studied by measuring tumor volumes post different treatments with PBS, OAV SG655-11R-P53, OAV SG655-mGM-CSF and OAV SG655-mGMP. Treatment with OAV SG655-mGMP induced significant xenograft growth inhibition, inflammation factor AIF1 expression and immune cells infiltration. Therefore, our OAV SG655-mGMP provides a novel platform to arm OVs to target cancer stem cells.

Argonaute 2 promotes angiogenesis via the PTEN/VEGF signaling pathway in human hepatocellular carcinoma.

AIM: Argonaute2 (AGO2) protein is the active part of RNA-induced silencing complex, cleaving the target mRNA strand complementary to their bound siRNA. An increasing number of miRNAs has been identified as essential to angiogenesis of hepatocellular carcinoma (HCC). In this study we investigated how AGO2 affected HCC angiogenesis. METHODS: Human HCC cell lines HepG2, Hep3B, Huh7, SMMC-7721, Bel-7404, MHCC97-H and LM-3, and human umbilical vein endothelial cells (HUVEC) were tested. The expression of AGO2 in HCC cells was knocked down with siRNA and restored using recombinant adenovirus expressing Ago2. The levels of relevant mRNAs and proteins were examined using RT-PCR, Western blot and EILSA. Nude mice were implanted with Huh7 or SMMC-7721 cells, and tumor volumes were measured. After the mice were euthanized, the xenograft tumors were used for immunohistological analysis. RESULTS: In 6 HCC cell lines, AGO2 protein expression was significantly correlated with VEGF expression (r=+0.79), and with VEGF secretion (r=+0.852). Knockdown of Ago2 in Huh7 cells and SMMC-7721 cells substantially decreased VEGF expression, whereas the restoration of AGO2 reversed both VEGF expression and secretion. Furthermore, knockdown of Ago2 significantly up-regulated the expression of PTEN (a tumor suppressor involved in the inhibition of HCC angiogenesis), and vice versa. Moreover, the specific PTEN inhibitor bisperoxovanadate (7, 14, 28 nmol/L) dose-dependently restored the expression of VEGF and the capacity of HCC cells to induce HUVECs to form capillary tubule structures. In the xenograft nude mice, knockdown of Ago2 markedly suppressed the tumor growth and decreased PTEN expression and CD31-positive microvascular in the xenograft tumors. CONCLUSION: A direct relationship exists between the miRNA processing machinery AGO2 and HCC angiogenesis that is mediated by the AGO2/PTEN/VEGF signaling pathway. The results suggest the high value of Ago2 knockdown in anti-angiogenesis therapy for HCC.

Malignant transformation rate and p53, and p16 expression in teratomatous skin of ovarian mature cystic teratoma.

OBJECTIVE: To investigate the incidence of malignant transformation and P53 and P16 expression in teratomatous skin of ovarian mature cystic teratoma. MATERIALS AND METHODS: Data on ovarian teratoma specimens in nearly 10 years were reviewed. P53 and P16 expression were detected by immunohistochemistry in 25 cases of teratomatous skin of ovarian mature cystic teratoma, 20 cases of squamous cell carcinoma and 2 cases of squamous cell carcinoma originated from teratomatous skin. RESULTS: Of 1913 cases of ovarian mature cystic teratoma in nearly 10 years, only two cases of squamous cell carcinoma were found in teratomatous skin, with malignant transformation rate of 0.1045%. P53 expression was detected in 2 cases squamous cell carcinoma originated from teratomatous skin and P16 overexpression in one. There were no expressions of P53 and P16 in 25 cases of teratomatous skin of ovarian mature cystic teratoma. Of 20 cases of squamous cell carcinoma P53 overexpression (positive rate of 55%) was detected in 11 cases, P16 overexpression (positive rate of 35%) in 7 cases. The positive rates of P53 and P16 expression in squamous cell carcinomas were significantly higher than that in the teratomatous skins (p< 0.001, p= 0.002). CONCLUSIONS: There was low risk of malignant transformation in teratomatous skin of ovarian mature cystic teratoma which can be explained by lower P53 and P16 expressionin teratomas than that in squamous cell carcinoma.

XPD Lys751Gln and Asp312Asn polymorphisms and susceptibility to skin cancer: a meta-analysis of 17 case-control studies.

BACKGROUND: Numerous studies have explored the influence of XPD Lys751Gln and/or Asp312Asn polymorphisms on skin cancer susceptibility. However, the results remain inconclusive. To derive a more precise estimation, we conducted a comprehensive search to identify all available published studies and performed a meta-analysis. MATERIALS AND METHODS: Electronic literature searches of the PubMed, CBM and CNKI databases were performed up to March 2014. Odds ratios (ORs) with 95% confidence intervals (CIs) were applied to assess the strength of associations. RESULTS: Seventeen case-control studies were included with a total sample size of 6, 113 cases and 11, 074 controls for the XPD Lys751Gln polymorphism, and 10 studies (3, 840cases and 7, 637 controls) for the XPD Asp312Asn polymorphism were pooled for analysis. Overall, no significant associations were found between the XPD Lys751Gln polymorphism and skin cancer risk in any genetic model. On stratified analysis by tumor type, XPD Lys751Gln polymorphism was not associated with increased risk of non-melanoma skin cancer, but was significantly related with increased risk of cutaneous melanoma (Gln/Gln vs Lys/Lys: OR=1.15, 95%CI=1.02-1.29, p=0.023; dominant model: OR=1.09, 95%CI=1.01-1.18, p=0.036). For the XPD Asp312Asn polymorphism, no significant association with skin cancer risk was observed in overall or subgroup analyses. CONCLUSIONS: The present meta-analysis suggests that the XPD Lys751Gln polymorphism may contribute to the risk of cutaneous melanoma from currently available evidence. Further investigations are needed to obtain more insight into possible roles of these two polymorphisms in skin carcinogenesis.