Zinc finger protein 367 exerts a cancer-promoting role in small cell lung cancer by influencing the CIT/LATS2/YAP signaling cascade.

A remarkable cancer-related role of zinc finger protein 367 (ZNF367) has been demonstrated in multiple malignancies. However, whether ZNF367 has a role in small-cell lung cancer (SCLC) remains unexplored. The purpose of this work was to explore the potential role and mechanism of ZNF367 in SCLC. In silico analysis using the Gene Expression Omnibus (GEO) dataset revealed high levels of the ZNF367 transcript in SCLC. Examination of clinical tissues confirmed the significant abundance of ZNF367 in SCLC tissues compared with adjacent non-malignant tissues. The genetic depletion of ZNF367 in SCLC cells led to remarkable alterations in cell proliferation, the cell cycle, colony formation and chemosensitivity. Mechanistically, ZNF367 was shown to regulate the activation of yes-associated protein (YAP) associated with the up-regulation of phosphorylated large tumour suppressor kinase 2 (LATS2). Further investigation revealed that ZNF367 affected the LATS2-YAP cascade by regulating the expression of citron kinase (CIT). Re-expression of constitutively active YAP diminished the tumour-inhibiting function of ZNF367 depletion. Xenograft experiments confirmed the tumour-inhibiting effect of ZNF367 depletion in vivo. In summary, our results demonstrate that the inhibition of ZNF367 displays anticancer effects in SCLC by inhibiting YAP activation, suggesting it as a potential druggable oncogenic target.

NDRG2 acts as a negative regulator of the progression of small-cell lung cancer through the modulation of the PTEN-AKT-mTOR signalling cascade.

N-myc downstream-regulated gene 2 (NDRG2) has been recognised as a negative regulator of the progression of numerous tumours, yet its specific role in small-cell lung carcinoma (SCLC) is not fully understood. The purpose of the current study was to investigate the biological role and mechanism of NDRG2 in SCLC. Initial investigation using the Gene Expression Omnibus (GEO) dataset revealed marked downregulation of NDRG2 transcripts in SCLC. The decreased abundance of NDRG2 in SCLC was verified by examining clinical specimens. Increasing NDRG2 expression in SCLC cell lines caused significant changes in cell proliferation, cell cycle progression, colony formation, and chemosensitivity. NDRG2 overexpression decreased the levels of phosphorylated PTEN, AKT and mTOR. In PTEN-depleted SCLC cells, the upregulation of NDRG2 did not result in any noticeable impact on AKT or mTOR activation. Additionally, the reactivation of AKT reversed the antitumour effects of NDRG2 in SCLC cells. Notably, increasing NDRG2 expression retarded the growth of SCLC cell-derived xenografts in vivo. In conclusion, NDRG2 serves as an inhibitor of SCLC, and its cancer-inhibiting effects are achieved through the suppression of AKT/mTOR via the activation of PTEN. This work suggests that NDRG2 is a potential druggable target for SCLC treatment.

Lipopolysaccharide induces skin scarring through the TLR4/Myd88 inflammatory signaling pathway in dermal fibroblasts.

Skin scarring is a frequent complication of the wound healing process. Bacterial contamination and prolonged inflammation in wounds are thought to play significant roles during scar formation, but little is known about their specific mechanisms of action. In this study, hypertrophic scar derived fibroblasts (HSFs) and paired normal skin derived fibroblasts (NSFs) were used to evaluate the effects of lipopolysaccharide (LPS) on inflammation-induced skin scarring and explore the inflammation-mediated mechanism of activity of LPS on dermal fibroblasts. LPS was found to significantly upregulate the expression of the proinflammatory molecules TLR4, Myd88, TRAF6, and p65, and the fibrosis-related proteins Col I, Col III, and α-SMA, in NSFs. Blocking Myd88 expression with T6167923 downregulated the expression of Col I, Col III, and α-SMA, whereas activating Myd88 expression with CL075 significantly upregulated their expression in LPS-treated NSFs. LPS was found to delay wound healing and increase skin scarring in cell and mouse models. These results showed that LPS could induce scar formation through the TLR4/Myd88 signaling pathway in dermal fibroblasts, suggesting that the downregulation of excessive inflammation in wound tissues inhibits skin scarring and improves scar appearance.

Hsa-miR-1269a up-regulation fosters the malignant progression of esophageal squamous cell carcinoma via targeting FAM46C.

Esophageal squamous cell carcinoma (ESCC) is a malignancy of the alimentary tract resulting in death worldwide. The role and underlying mechanism of hsa-miR-1269a in the progression of ESCC remain unclear. In this study, hsa-miR-1269a was screened by differential expression analysis in TCGA, and its target gene FAM46C was predicted. qRT-PCR was conducted to assay the expression of hsa-miR-1269a and FAM46C in ESCC cells. The results showed that hsa-miR-1269a was upregulated in ESCC tissues and cell lines. Hsa-miR-1269a overexpression stimulated the proliferation, migration, and invasion capacities of ESCC cells, and FAM46C overexpression inhibited these phenotypes. Dual-luciferase assay verified that hsa-miR-1269a could target FAM46C. Next, qRT-PCR and western blot demonstrated that hsa-miR-1269a overexpression downregulated FAM46C. Rescue experiments revealed that hsa-miR-1269a accelerated the malignant progression of ESCC through FAM46C down-regulation. These results indicate that the interaction between hsa-miR-1269a and FAM46C plays a regulatory role in driving the malignant progression of ESCC cells, thereby providing a novel molecular mechanism for understanding ESCC.

Plasma levels of D-dimer and fibrin degradation products correlate with bullous pemphigoid severity: a cross-sectional study.

Bullous pemphigoid (BP), the most frequent blistering dermatosis in the elderly, is associated with increased mortality. The severity of BP can be assessed by detecting the anti-BP180 immunoglobulin G (IgG) concentration, but the lab test is not available in many community clinics. BP patients are usually in a hypercoagulable state with increased levels of D-dimer and fibrin degradation products (FDPs). We aimed to evaluate the use of D-dimer and FDPs in assessing BP severity. We compared the levels of plasma D-dimer, plasma FDPs, eosinophil counts, eosinophil cationic protein, and serum anti-BP180 IgG concentration between 48 typical BP patients and 33 Herpes zoster (HZ) patients (control group). Correlational analyses were conducted to determine the relationships between the lab values and common BP severity markers. The plasma D-dimer and FDP levels were higher in BP patients than in HZ controls (D-dimer: 3297 ± 2517 µg/L vs. 569.70 ± 412.40 µg/L; FDP: 9.74 ± 5.88 mg/L vs. 2.02 ± 1.69 mg/L, respectively, P < 0.0001). Significant positive correlations were found between D-dimer/FDP levels and BP severity markers (i.e. anti-BP180 IgG concentration [D-dimer: r = 0.3928, P = 0.0058; FDP: r = 0.4379, P = 0.0019] and eosinophil counts [D-dimer: r = 0.3625, P = 0.0013; FDP: r = 0.2880, P = 0.0472]) in BP patients. We also found an association between FDP and urticaria/erythema lesions (r = 0.3016, P = 0.0372), but no other BPDAI components. In 19 BP patients with complete remission after systemic glucocorticoid treatment, D-dimer and FDP levels decreased post-therapy (D-dimer: 5559 ± 7492 µg/L vs. 1738 ± 1478 µg/L; P < 0.0001; FDP: 11.20 ± 5.88 mg/L vs. 5.13 ± 3.44 mg/L; P = 0.0003), whereas they did not in BP patients with treatment resistant. Plasma D-dimer and FDP are convenient markers to evaluate BP severity assistant on BPDAI and eosinophil counts. FDP is also helpful for inflammatory lesions in BP patients.

S100A8 and S100A9, both transcriptionally regulated by PU.1, promote epithelial-mesenchymal transformation (EMT) and invasive growth of dermal keratinocytes during scar formation post burn.

S100 calcium-binding protein A8 (S100A8) and S100A9 are small molecular weight calcium-binding regulatory proteins that have been involved in multiple chronic inflammatory diseases. However, the role of S100A8 and S100A9 in keratinocytes in wounded skin and how they are regulated during this process are still unclear. Here, we found that S100A8 and S100A9 were both upregulated in burn-wounded skins in vivo and thermal-stimulated epidermal keratinocytes in vitro, accompanied by increased levels of epithelial-mesenchymal transition (EMT). Then, we demonstrated that upregulation of S100A8 and S100A9 alone or together enhanced characteristics of EMT in normal keratinocytes, manifested by excessive proliferation rate, abnormal ability of cell invasion, and high expression levels of EMT marker proteins. The transcription factor PU box-binding protein (PU.1) bound to the promoter regions and transcriptionally promoted the expression of S100A8 and S100A9 both in the human and mice, and it had strong positive correlations with both S100A8 and S100A9 protein levels in burned skin in vivo. Moreover, PU.1 positively regulated expression of S100A8 and S100A9 in a dose-dependent manner, and enhanced EMT of keratinocytes in vitro. Finally, through the burn mouse model, we found that PU.1-/- mice displayed a lower ability of scar formation, manifested by smaller scar volume, thickness, and collagen content, which could be enhanced by S100A8 and S100A9. In conclusion, PU.1 transcriptionally promotes expression of S100A8 and S100A9, thus positively regulating epithelial-mesenchymal transformation (EMT) and invasive growth of dermal keratinocytes during scar formation post burn.

SphK1 promotes development of non­small cell lung cancer through activation of STAT3.

Sphingosine kinase1 (SphK1) is an oncogenic enzyme that regulates tumor cell apoptosis, proliferation and survival. SphK1 has been reported to promote the development of non­small cell lung cancer (NSCLC), although the underlying mechanism remains to be determined. The aim of the present study was to examine the expression and function of SphK1 in NSCLC and to explore the underlying molecular mechanism. The results of the present study demonstrated that SphK1 expression was upregulated in NSCLC tissues and cell lines. Overexpression of SphK1 increased the proliferation and migration of NSCLC cells. Additionally, overexpression of SphK1 induced expression of antiapoptotic and migration­associated genes, such as Bcl­2, matrix metallopeptidase 2 and cyclin D1. Of note, signal transducer and activator of transcription 3 (STAT3) was also activated in the SphK1­overexpressing cells. By treatment with a STAT3 inhibitor, it was demonstrated that the SphK1­induced changes in expression of target genes, as well as the increase in proliferation and migration of NSCLC cells were mediated by STAT3. In conclusion, the effects of SphK1 overexpression on the development of NSCLC were demonstrated to be mediated by the activation of STAT3. These results suggested that inhibition of the SphK1­STAT3 axis may be a potential strategy for the treatment of NSCLC.

TWEAK Promotes the Proliferation of Squamous Cell Carcinoma Cells Through Activating cIAP1 Signals.

Recent studies showed that tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) induces the proliferation of squamous cell carcinoma (SCC) cells. However, the precise mechanism underlying such effect of TWEAK remains unclear. This study was designed to elucidate the role of cellular inhibitor of apoptosis 1 (cIAP1) in TWEAK-induced proliferation of SCC cells. Human SCC cells (SCC-13, A431, and SCC-9) were cultured in vitro, receiving the stimulation of TWEAK or TNF-related apoptosis-inducing ligand (TRAIL). We found that TWEAK induced cytoplasmic cIAP1 importation and RIP1 ubiquitination in cells, followed by the activation of canonical nuclear factor kappa B signals. MV1, a cIAP1 inhibitor, abrogated TWEAK-induced proliferation of these cells. Moreover, the interaction between TWEAK and its receptor, fibroblast growth factor-inducible 14 (Fn14), enhanced the expression of TRAIL receptor types 3 and 4 (TRAIL-R3/4). Furthermore, the transfection of TRAIL-R3/4 siRNA abrogated the promotion effect of TWEAK on SCC-13 cell proliferation and cIAP1 expression. Therefore, TWEAK/Fn14 interaction promotes the proliferation of SCC cells through activating cIAP1 signals. Targeting the downstream cIAP1 signals might attenuate the effect of TWEAK on SCC cells.

Evaluation of genetic susceptibility between systemic lupus erythematosus and GRB2 gene.

Multiple lines of evidence have shown that systemic lupus erythematosus (SLE) is attributable to both genetic and environmental factors. The product of GRB2 is a key factor in the activation of B cells and has been reported to be significantly associated with SLE in European populations. In the study, we aimed to investigate the relationship between GRB2 and SLE. A total of 1,710 Han Chinese women comprising 567 SLE patients and 1,143 controls were recruited to genotype 20 selected tagging SNPs. We tested the potential association between 13 clinical variables of SLE and the significant polymorphisms related to SLE. The eQTL data were extracted from the GTEx database to examine the functional consequences of the targeted SNPs. A significant association signal was identified between rs36023980 and SLE in both genotypic and allelic analyses (OR = 0.61, P = 0.0003). Complement inhibition was shown to be significantly associated with the genotypes of SNP rs36023980 in SLE patients (Pgenotype = 0.003). Further stratification analyses showed that the genetic association signal of SNP rs36023980 on SLE could only be identified in cases with complement inhibition. SNP rs36023980 was also identified to be significantly associated with the expression of GRB2 in whole blood and sun-exposed skin. In conclusion, our findings confirm the results from the previous GWAS and are the first to report the association of GRB2 with SLE in Han Chinese population.

Knockdown of FOXM1 inhibits activation of keloid fibroblasts and extracellular matrix production via inhibition of TGF-ß1/Smad pathway.

Keloid is characterized by overactive fibroblasts. Forkhead box M1 (FOXM1) is transcription factor that plays important roles in the progression of fibrosis. However, the role of FOXM1 in keloid has not been elucidated. In the present study, we examined the expression levels of FOXM1 in clinical keloid tissue specimens and primary keloid fibroblasts (KFs). The results showed that FOXM1 levels were significantly increased in both keloid tissues and KFs. To further investigate the biological functions of FOXM1, FOXM1 was knocked down in KFs by transfection with small interfering RNA targeting FOXM1 (si-FOXM1). Knockdown of FOXM1 inhibited transforming growth factor-ß1 (TGF-ß1)-induced cell proliferation and migration of KFs. Besides, the increased expressions of collagen (coll I), connective tissue growth factor (CTGF), and α-smooth muscle actin (α-SMA) in TGF-ß1-induced KFs were suppressed by si-FOXM1 transfection. Furthermore, TGF-ß1-induced increase in p-Smad2 and p-Smad3 expressions was attenuated by FOXM1 knockdown. These data indicated that knockdown of FOXM1 inhibited TGF-ß1-induced KFs activation and extracellular matrix (ECM) accumulation, which was attributed to the inhibition of TGF-ß1/Smad pathway.

Loss of Beclin1 Expression and Nrf2 Overexpression are Associated with Poor Survival of Patients with Non-Small Cell Lung Cancer.

BACKGROUND: Nrf2 pathway and autophagy are abnormally activated in response to cellular stress in various types of human cancers. In this study, we selected Beclin1 as an enter point to discuss the relationship between Nrf2 pathway and autophagy, and defined their associations with clinic pathological features and survival of the patients. METHOD: NSCLC specimens were processed for immunohistochemical and qRT-PCR to analyses the expression of Beclin1 and Nrf2. Kaplan-Meier method and log-rank test were used in the survival data. RESULTS: Beclin1 protein level was found to be significantly associated with more advanced TNM stage (P = 0.035), lymph node metastasis (P = 0.017) and distant metastasis (P = 0.005). The expression of Nrf2 protein was associated with larger tumor size (P = 0.032), more advanced TNM stage (P = 0.011), lymph node metastasis (P = 0.045) and distant metastasis (P = 0.013). Beside there was a strong inverse relationship between Beclin1 and Nrf2 expression in the NSCLC tissues. Distant metastasis, Beclin1, Nrf2, and Beclin1-/Nrf2+ expression was conformed to be independent prognostic factors of patients. CONCLUSION: Both Nrf2 overexpression and Beclin1 lower-expression are independent indicators of a poor prognosis in NSCLC patients.

Potential of siRNA-albumin complex against cancer.

RNA interference is a highly specific as well as efficient technology for gene therapy application in molecular oncology. The present study was planned to develop an efficient and stable tumor selective delivery mechanism for siRNA gene therapy for the purpose of both diagnosis as well as therapy. We have used 20 Male wistar rats for the formation of colon cancer model and utilized albumin as carrier molecule for the delivery of siRNA against vascular endothelial growth factor receptor 2 (VEGF R2). The study results confirmed efficient delivery of siRNA at tumor site as confirmed by tagging of siRNA-albumin complex with 99mTC. Moreover, the expression of VEGF also showed decline after efficient delivery of siRNA at tumor site. The study concluded that albumin is an efficient molecule for the efficient delivery of siRNA at tumor sites.

Combined Evaluation of Expression of CXCR4 and Nrf2 as Prognostic Factor for Patients with Gastric Carcinoma.

BACKGROUND: CXC Chemokine Receptor 4 (CXCR4) and NFE-related factor 2 (Nrf2) have been observed implicated with cell malignant behavior of human cancers. AIMS: In this study, we detected their expression in gastric carcinoma (GC) tissue specimens and related the result with clinicopathological data and patient survival. METHODS: 120 GC and compared normal tissue specimens were processed to analyse the expression of CXCR4 and Nrf2. We found that the expression of CXCR4 and Nrf2 was dramatically increased in GC tissues when compared to the distant non-cancer tissues (P<0.05). CXCR4 overexpression was associated with the depth of invasion (P= 0.006), Histological grade (P=0.018), TNMstage (P= 0.021), lymph node metastasis (P < 0.001) and distant metastasis (P=0.026), whereas overexpression of Nrf2 protein was significantly associated with tumor size (P=0.045), Histological grade (P=0.026), TNMstage (P= 0.020), lymph node metastases (P < 0.001) and distant metastasis (P=0.008). Furthermore, we observed a significant co-expression of CXCR4 and Nrf2 expression in GC specimens. RESULTS: In the survival part, we found that GC patients with CXCR4+ and Nrf2+ had worse outcomes. The significant prognostic indicators are age, tumor size, histological grade, TNMstage, CXCR4, Nrf2, and coexpression of CXCR4 and Nrf2 in GC patients. Multivariate analysis showed that TNMstage and CXCR4+/Nrf2+ expression were risk factors. Above all we come to the conclusion that the expression of CXCR4 might partly be regulated by the level of Nrf2 and both positive expressions suggest poor prognosis of GC patients.

MicroRNA-384 represses the growth and invasion of non-small-cell lung cancer by targeting astrocyte elevated gene-1/Wnt signaling.

Dysregulation of microRNA (miRNA) expression is a critical event in the development and progression of non-small-cell lung cancer (NSCLC). miR-384 has been identified as a novel cancer-related miRNA in numerous cancers, but little is known about its role and functional mechanism in NSCLC. In this study, we found that miR-384 was significantly downregulated in NSCLC tissues and cell lines. The overexpression of miR-384 repressed the growth and invasion of NSCLC cells, whereas its suppression showed the opposite effect. Moreover, astrocyte elevated gene-1 (AEG-1) was identified as a target gene of miR-384. The overexpression of miR-384 significantly decreased AEG-1 expression and Wnt signaling, whereas its suppression promoted this pathway. Furthermore, miR-384 was inversely correlated with AEG-1 expression in NSCLC tissues. Additionally, restoration of AEG-1 expression in miR-384-overexpressing cells significantly reversed the antitumor effects of miR-384. Taken together, these results reveal that miR-384 represses the growth and invasion of NSCLC cells by targeting AEG-1. Our study suggest that miR-384 and AEG-1 may serve as potential targets for the diagnosis and treatment of NSCLC.

Inhibition of NOB1 by microRNA-330-5p overexpression represses cell growth of non-small cell lung cancer.

MicroRNAs (miRNAs) play critical roles in the development and progression of various cancers, including non-small-cell lung cancer (NSCLC). Studies have suggested that miR-330-5p is involved in the progression of several cancers. However, the role of miR-330-5p in NSCLC remains unclear. We investigated the effect on and mechanism of miR-330-5p in the progression of NSCLC. We found that miR-330-5p was significantly downregulated in NSCLC tissues and cell lines as detected by real-time quantitative polymerase chain reaction (RT-qPCR). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), bromodeoxyuridine (BrdU), colony formation and cell cycle assays showed that overexpression of miR-330-5p markedly inhibited cell growth. Annexin V-FITC/PI and caspase-3 activity assays showed that overexpression of miR-330-5p significantly promoted cell apoptosis of NSCLC cells. Bioinformatics analysis and dual-luciferase reporter assays confirmed NIN/RPN12 binding protein 1 (NOB1) as a target gene of miR-330-5p. RT-qPCR and Western blot analysis showed that overexpression of miR-330-5p inhibited the expression of NOB1 as well as cyclin D1 and cyclin-dependent kinase 4 in NSCLC cells. Moreover, overexpression of NOB1 markedly reversed the miR­330-5p-mediated inhibitory effect on NSCLC cell growth. Correlation analysis showed that miR­330-5p expression was inversely correlated with NOB1 mRNA expression in NSCLC tissues. Taken together, our results indicate that miR-330-5p inhibits NSCLC cell growth through downregulation of NOB1 expression. Our study suggests that miR-330-5p may serve as a potential therapeutic target for the treatment of NSCLC.

CTRP3 attenuates hepatic stellate cell activation through transforming growth factor-ß/Smad signaling pathway.

Activation of hepatic stellate cells (HSCs) plays a pivotal role in the development of liver fibrosis. C1q/tumor necrosis factor-related protein 3 (CTRP3), a member of CTRPs, was involved in fibrosis. However, little is known about the role of CTRP3 in liver fibrosis. This study aimed to determine its role in liver fibrosis and explore the possible mechanism. Our results demonstrated that CTRP3 was lowly expressed in liver fibrosis tissues and activated HSCs. Overexpression of CTRP3 inhibited the proliferation and migration of HSCs, as well as suppressed the expression of extracellular matrix (ECM) in transforming growth factor-ß1 (TGF-ß1)-stimulated HSC-T6 cells. Furthermore, CTRP3 overexpression greatly inhibited the expression level of phosphorylation of Smad3 in TGF-ß1-stimulated HSC-T6 cells. In conclusion, the present study demonstrated that CTRP3 inhibited the proliferation and migration of TGF-ß1-induced HSC-T6 cells and attenuated liver fibrosis, at least in part, through inhibiting the Smad signaling pathway. These findings suggest that CTRP3 may be a promising therapeutic target for the treatment of liver fibrosis.

[Role of prostate stem cell antigen in human pancreatic carcinoma: a tissue microarray-based study].

OBJECTIVE: To investigate the expression of prostate stem cell antigen (PSCA) in human pancreatic carcinoma and explore its role in the oncogenesis of pancreatic cancer. METHODS: A pancreatic carcinoma tissue microarray was constructed, which contained 10 normal adult pancreas tissues, 12 chronic pancreatitis tissues and 78 pancreatic carcinomas. Immunohistochemistry was employed to detect the expression of PSCA, and the relation between PSCA expression and the clinicopathological factors of pancreatic carcinoma was analyzed. RESULTS: The positivity rate of PSCA in pancreatic carcinoma was 79.5% (62/78), and PSCA staining was more intense in the malignant cells than in the benign cells (chi2=15.81, P<0.005) and chronic pancreatitis tissues (chi2=11.33, P<0.005). No obvious association was found between PSCA expression and the other variables of pancreatic carcinoma (including gender, age at surgery, tumor grade, and TNM stages). CONCLUSION: The expression of PSCA can be related to the development of pancreatic cancer, but not to the clinicopathological factors of the tumor.

[Expression of prostate stem cell antigen and Claudin-4 in human pancreatic carcinoma].

OBJECTIVE: To investigate the expressions of prostate stem cell antigen (PSCA) and Claudin-4 in human pancreatic carcinoma and to discuss its role in the ontogenesis of pancreatic cancer. METHODS: Pancreatic carcinoma tissue microarray was constructed, containing 100 cores of 10 normal adult pancreas tissues, 12 chronic pancreatitis tissues, and 78 pancreatic carcinomas. The expressions of PSCA and Claudin-4 were detected using immunohistochemical method and the relationship between PSCA and Claudin-4 and the pancreatic carcinoma was analyzed. RESULTS: The positive expression rates of PSCA and Claudin-4 protein in pancreatic carcinoma were 79. % and 88. % respectively. PSCA and Claudin-4 staining were more intense in malignant cells than in chronic pancreatic tissues and normal adult pancreas tissues. No evidence was found for an association between expressions of PSCA and Claudin-4 and other variables, including gender, age at surgery, and tumor grade. CONCLUSIONS: The expressions of PSCA and Claudin-4 are related to the pancreatic carcinomas. PSCA and Claudin-4 play a role in the development of pancreatic cancer, but PSCA and Claudin-4 are not correlated with the clinical pathology of tumor.