Decreased Expression of PDHE1α Predicts Worse Clinical Outcome in Esophageal Squamous Cell Carcinoma

BACKGROUND

Aerobic glycolysis is an important hallmark of cancer cells. Deficiency of pyruvate dehydrogenase component α subunit (PDHE1α) leads to mitochondrial dysfunction and promotes glycolysis. Therefore, studies on the expression of PDHE1α in cancer are warranted.

PATIENTS AND METHODS

The PDHE1α protein was immunohistochemically investigated and analyzed in 157 samples of surgically dissected esophageal squamous cell carcinoma (ESCC) and 21 'normal' esophageal epithelia tissues.

RESULTS

PDHE1α protein expression was lower in ESCC. Absence of PDHE1α protein expression in tumor cells was found in 77.1% of cases. Negativity for PDHE1α protein in tumor cells was correlated with poor tumor differentiation (p<0.05) and shorter overall survival (p<0.05).

CONCLUSION

Lack of PDHE1α protein expression in ESCC is associated with poor prognosis. Our findings also verify the existence of aerobic glycolysis switch in ESCC, and strongly advocate novel therapeutic strategies in reversing the Warburg effect in tumors.

[The effect of catalase on smoking related laryngeal squamous cell carcinoma]

OBJECTIVE

Investigate the effect of oxidative stress on the occurrence and development of laryngeal squamous cell carcinoma associated with smoking, and the clinical diagnostic value of catalase on smoking related laryngeal squamous cell carcinoma.

METHOD

Collecting 119 smokers(including the smoking related laryngeal cancer group 68 cases, the control group 51 cases), the indexes of catalase (CAT), malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione (GSH), nitric oxide (NO) in blood plasma and cancerous tissue in two groups were compared. The association between these oxidative stress indicators and the occurrence and severity of smoking related laryngeal squamous cell carcinoma was analysised by SPSS 17.0.

RESULT

(1) Compared with control group, the smoke frequency and amount, CAT, MDA, GSH increased significantly in the smoking related laryngeal cancer group (P = 0.000; 0.000; 0.000; 0.000; 0.000); whereas SOD, NO decreased (P = 0.000; 0.000). (2) The lower the differentiation degree, the higher the serum CAT (P = 0.000) and the higher CAT, MDA, GSH of larynx tissue (P = 0.000; 0.000; 0.000), but the lower the serum NO (P = 0.000) and the lower SOD, NO of larynx tissue (P = 0.000; 0.000); The higher the clinical stage, the higher CAT of serum and larynx tissue and the higher GSH of larynx tissue (P = 0.000; 0.001), the lower NO of larynx tissue (P = 0.009). (3) The serum CAT, MDA were independent risk factors of smoking related laryngeal squamous cell carcinoma (OR = 1.060, 2.475; P < 0.01, P < 0.05).

CONCLUSION

Oxidative stress is the key factor of the occurrence of smoking related laryngeal squamous cell carcinoma, and the CAT can be used as the indicator of clinical diagnosis of smoking related laryngeal squamous cell carcinoma.

Aberrant expression of CDK5 infers poor outcomes for nasopharyngeal carcinoma patients

PURPOSE

Aberrant expression of CDK5 involved in epithelial-to-mesenchymal transition had been reported in various types of cancers, but its functions in nasopharyngeal carcinoma have not been fully clarified yet. The principal purpose of this research was to investigate the clinicopathological significance of CDK5 and its potential effect on NPC carcinogenesis.

METHODS

Pre-treated formalin-fixed paraffin-embedded biopsy samples of 393 patients between January 2011 and December 2013 were collected for tissue microarrays (TMAs). Immunohistochemistry was performed on sequential TMA sections stained with antibodies against CDK5, EGFR and P53.

RESULTS

The expression of CDK5 in NPC tissues was significantly higher than that in normal nasopharyngeal tissues. Among squamous carcinomas, the expression of CDK5 in undifferentiated tissues was noticeably increased compared with that in differentiated tissues. NPC patients in advanced T category showed a perceptibly higher level of CDK5 than those in early T category. The relative level of CDK5 in NPC sufferers with lymph node metastasis was obviously higher than that of patients without. Compared with patients in early TNM stages, the relative expression level of CDK5 of those in advanced TNM stages was notably up-regulated. Moreover, the CDK5 expression was positively correlated with EGFR and P53 expression. Nevertheless, no significant association was observed between CDK5 and gender, age or histological type.

CONCLUSION

Overexpression of CDK5 might be considered as a warning signal for NPC. Consequently, CDK5 could serve as a potential target for diagnosis and gene therapy for NPC patients.

[Significance of serum neuron-specific enolase before treatment in predicting brain metastases and prognosis of advanced non-small cell lung cancer]

OBJECTIVE

To explore the value of serum neuron-specific enolase (NSE) before treatment in predicting brain metastases and prognosis of advanced non-small cell lung cancer (NSCLC).

METHODS

A total of 128 hospitalized patients with advanced NSCLC from Jan 2012 to Mar 2012 were followed up, and their clinicopathological data, serum NSE, carcinoembryonic antigen, cytokeratin 21-1 (cyfra21-1) levels, albumin (ALB), white blood cell (WBC) before treatment were analyzed retrospectively to determine the factors affecting brain metastasis and prognosis of advanced NSCLC.

RESULTS

Among the 128 NSCLC patients, 90 cases were of adenocarcinoma, 30 cases were of squamous cell carcinoma, and 8 cases were of large cell carcinoma. The median levels of pre-treatment NSE, CEA and cyfra21-1 were 13.6 ng/ml, 7.8 ng/ml and 6.1 ng/ml, respectively. The average levels of ALB and WBC were (35.41 ± 5.60) g/L and (8.16 ± 2.53) × 10⁹/ml, respectively. Multi-variate logistic regression analysis showed that serum NSE before treatment was associated with brain metastasis of advanced NSCLC (P = 0.030). Pre-treatment NSE levels were (34.18 ± 28.48) ng/ml in 28 patients with brain metastasis and (13.87 ± 4.49) ng/ml in 98 patients without brain metastasis (P < 0.05). The median survival time were 3.5 months in patients with normal levels of NSE, and 10.7 months in patients with elevated levels of NSE pre-treatment (P < 0.05).

CONCLUSIONS

A higher pre-treatment level of NSE is closely correlated with brain metastasis of advanced NSCLC, and can be used as a predictor of brain metastases in advanced NSCLC. High pre-treatment levels of NSE indicate a poor prognosis in advanced NSCLC patients.

Increased expression of carbonic anhydrase IX in oral submucous fibrosis and oral squamous cell carcinoma

BACKGROUND

Cumulative evidence has demonstrated that carbonic anhydrase IX (CAIX) is upregulated in many types of human cancers. We attempted to evaluate plasma levels of CAIX in patients with oral cancer and investigated whether plasma CAIX is correlated with the progression of this disease.

METHOD

In total, 191 patients with oral cancer, 30 patients with oral submucous fibrosis and 100 controls were recruited in this study. The plasma samples were collected and the levels of soluble CAIX in plasma were determined by the enzyme-linked immunosorbent assay (ELISA). Furthermore, the normal buccal mucosa fibroblast was challenged by arecoline, the major areca nut alkaloid, to assess the relationship between the levels of CAIX and areca nut chewing in oral cancer patients.

RESULTS

Results showed that patients with oral cancer exhibited significantly higher levels of soluble CAIX compared to controls (p<0.001). Plasma levels of CAIX in oral cancer patients were associated with clinical stages after adjusting for age and areca nut chewing (p<0.05). In addition, patients with areca nuts chewing had higher CAIX levels than those who have not chewed areca nuts. Total carbonic anhydrase activity and CAIX mRNA levels were significantly higher in oral submucous fibrosis fibroblasts than in normal buccal mucosa fibroblasts. Moreover, arecoline elevated CAIX expression in a dose-dependent manner in normal buccal mucosa fibroblasts.

CONCLUSIONS

Our results suggest that determining plasma levels of CAIX may be used as a non-invasive method for monitoring oral cancer progression and the involvement of areca quid chewing in oral carcinogenesis may be related to a higher expression of CAIX.

DATS suppresses growth of esophageal squamous cell carcinoma by regulation of ERK1/2

BACKGROUND

It is well known that garlics contain a large number of organosulfur compounds including diallyl trisulfide (DATS), which possess anticancer properties. However, the effects of DATS on esophageal squamous cell carcinoma (ESCC) growth are still poorly understood. In this study, we investigated the effects of DATS on ESCC cell growth in vivo and in vitro, as well as the associated signaling pathways.

METHODS

Cell proliferation was measured using the crystal violet assay. The transwell method was used to evaluate the effect of DATS on ESCC cell migration. Also, Western blot was performed to detect the activation of ERK1/2 and AKT1 responds to DATS. Finally, the effect of DATS on ESCC xenografts in nude mice was also investigated.

RESULTS

Our results showed that DATS significantly inhibited ESCC cell proliferation in a time- and dose-dependent manner. DATS time-dependently (p < 0.05) increased phosphorylation of ERK1/2, but not AKT1. Suppression of ERK1/2 activation with PD9805 also completely blocked DATS-inhibited ESCC cell proliferation. Meanwhile, DATS also robustly suppressed ESCC xenograft growth and increased ERK1/2 activation in nude mice.

CONCLUSIONS

Our finding demonstrated that DATS inhibits the proliferation of ESCC cells by activation of ERK1/2 in vitro and in vivo. These findings revealed that DATS could be used for therapeutic intervention for human ESCC.

Impact of alcohol dehydrogenase gene 4 polymorphisms on esophageal squamous cell carcinoma risk in a Chinese population

Background

Esophageal squamous cell carcinoma (ESCC) is very common in China and is also one of the most common cancers worldwide. The purpose of this study was to examine the associations between genetic variants of various cancer-related genes and the risk of ESCC.

Methods

In this study, we first examined the association between 18 potentially disruptive genetic variants of 17 genes, including alcohol dehydrogenase 4 (ADH4) and checkpoint kinase 2 (CHEK2), and ESCC risk in a Hangzhou population of 617 patients matched with 534 controls. Among the 18 single nucleotide polymorphisms (SNPs), two were validated in a Jinan population of 540 patients matched with 550 controls.

Results

Sixteen SNPs in 15 genes, including CHEK2, did not have significantly different allele frequency distributions between ESCC patients and control subjects. A significantly increased risk of developing ESCC was revealed in subjects with the AA genotype of rs3805322 (ADH4) compared with those with the AG or GG genotype by unconditional univariate logistic regression analysis. Using a dominant model, the CC genotype of rs4822983 (CHEK2) had a marginally significant protective effect compared to the CT and TT genotypes. The association of ESCC risk with these two SNPs (rs3805322 and rs4822983) was further validated in a Jinan case-control set. Individuals with the ADH4 rs3805322 AA or AG genotype had ORs of 1.10 (95% CI = 0.81–1.49, P < 0.001) or 1.86 (95% CI = 1.33–2.59, P = 0.559), respectively, for developing ESCC compared with individuals with the GG genotype. CHEK2 rs4822983 CC carriers showed a marginally significantly decreased ESCC risk compared with those carrying the CT and TT genotypes in the validation set (95% CI = 0.61–1.01, P = 0.064). However, no evidence of interaction existed between the two SNPs and smoking or drinking in the Jinan case-control set.

Conclusions

In conclusion, this current study provides substantial evidence that genetic polymorphisms of rs3805322 in the ADH4 gene may be associated with an increased risk of developing ESCC in two Chinese Han populations. Future studies to address the biological function of this polymorphism in the development of ESCC are warranted.

[Expression and clinical significance of MMP9 in sinonasal squamous cell carcinoma]

OBJECTIVE

We detected expression of MMP9 to discuss its role in the occurrence and development of sinonasal squamous cell carcinoma.

METHOD

The immunohistochemical staining, real-time PCR and Western blot were used to measure the expression of MMP9 in sinonasal squamous cell carcinoma tissues (Experimental group) and corresponding normal mucosa tissues (Control group). Relationship between MMP9 and the main clinical features of patients with sinonasal squamous cell carcinoma was analysed.

RESULT

Positive expression rates of MMP9 in sinonasal squamous cell carcinoma tissues and corresponding normal mucosa tissues were 81. 25% and 18. 52% respectively. Positive expression rate of MMP9 was not significantly correlated with patient's age and gender (P>0. 05), but correlated with pathological type (P<0. 05). The expression of MMP9 mRNA in sinonasal squamous carcinoma tissues was 30. 66 times of tissues adjacent to carcinoma (P<0. 05). Western blot analysis also showed that the expression of MMP9 protein in squamous carcinoma tissues was significantly higher than tissues adjacent to carcinoma (P<. 05).

CONCLUSION

The expression of MMP9 was significantly higher in the sinonasal squamous cell carcinoma and correlated with the degree of differentiation. The results suggest that MMP9 may play a role in the occurrence and development of sinonasal squamous cell carcinoma and degree of malignancy from the protein and cellular and molecular level. The higher degree of malignancy, the stronger expression.

Expression of Wnt11 and Rock2 protein with clinical characteristics of esophageal squamous cell carcinoma in Kazakh and Han patients

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is one of the most malignancies with a very poor outcome in China. Wnt11 and Rock2, new identified proteins highly associated with metastasis of many cancers, which were never reported in esophageal squamous cell carcinoma (ESCC). Here we measured the expression levels of Wnt11 and Rock2 in tissues from 265 patients with ESCC. Immunohistochemical staining was employed to detect the correlation of Wnt11 and Rock2 expression with clinicopathological features.

METHODS

The expression of Wnt11 and Rock2 was detected by immunohistochemistry in esophageal squamous cell carcinomas and normal esophageal tissues. A chi-square test was used to assess the statistical significance of the correlations between Wnt11, Rock2 expression and different clinicopathological parameters, respectively.

RESULTS

The high-expression of Wnt11 and Rock2 was observed in ESCCs. Seventy-five cases of ESCC (51.7%) showed a positive expression of Wnt11, which indicated a significant association with the AJCC stage (P=0.007). Ninety-eight cases of ESCC (65.5%) showed a positive expression of Rock2, which indicated a significant association with ethnic background. There were no close correlations between Rock2 expression and gender, tumor location, AJCC stage, lymph node metastasis. Specifically, the expression of Rock2 was significantly different between Hans and Kazaks ethnicities (P=0.000). In Kaplan-Meier curve analysis, no significant correlation was observed between the expression of Wnt11, Rock-2 and the poor prognosis of ESCCs.

CONCLUSION

Our finding suggests that the over-expression of Rock2 may play an important role in the carcinogenesis and progression, and may become a new underlying molecular marker in the diagnosis and treatment in ESCC.

MiR-451 inhibits proliferation of esophageal carcinoma cell line EC9706 by targeting CDKN2D and MAP3K1

AIM: To investigate the underlying molecular mechanisms of miR-451 to inhibit proliferation of esophageal carcinoma cell line EC9706.

METHODS: Assays for cell growth, apoptosis and invasion were used to evaluate the effects of miR-451 expression on EC cells. Luciferase reporter and Western blot assays were used to test whether cyclin-dependent kinase inhibitor 2D (CDKN2D) and MAP3K1 act as major targets of miR-451.

RESULTS: The results showed that CDKN2D and MAP3K1 are direct targets of miR-451. CDKN2D and MAP3K1 overexpression reversed the effect of miR-451. MiR-451 inhibited the proliferation of EC9706 by targeting CDKN2D and MAP3K1.

CONCLUSION: These findings suggest that miR-451 might be a novel prognostic biomarker and a potential target for the treatment of esophageal squamous cell carcinoma in the future.

Anticancer Effect of Ursodeoxycholic Acid in Human Oral Squamous Carcinoma HSC-3 Cells through the Caspases

Bear bile was used as a traditional medicine or tonic in East Asia, and ursodeoxycholic acid (UDCA) is the most important compound in bear bile. Further, synthetic UDCA is also used in modern medicine and nutrition; therefore, its further functional effects warrant research, in vitro methods could be used for the fundamental research of its anticancer effects. In this study, the apoptotic effects of UDCA in human oral squamous carcinoma HSC-3 cells through the activation of caspases were observed by the experimental methods of MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide) assay, DAPI (4’,6-diamidino-2-phenylindole) staining, flow cytometry analysis, RT-PCR (reverse transcription-polymerase chain reaction) assay and Western blot assay after HSC-3 cells were treated by different concentrations of UDCA. With 0 to 400 μg/mL UDCA treatment, UDCA had strong growth inhibitory effects in HSC-3 cells, but had almost no effect in HOK normal oral cells. At concentrations of 100, 200 and 400 μg/mL, UDCA could induce apoptosis compared to untreated control HSC-3 cells. Treatment of 400 μg/mL UDCA could induce more apoptotic cancer cells than 100 and 200 μg/mL treatment; the sub-G1 DNA content of 400 μg/mL UDCA treated cancer cells was 41.3% versus 10.6% (100 μg/mL) and 22.4% (200 μg/mL). After different concentrations of UDCA treatment, the mRNA and protein expressions of caspase-3, caspase-8, caspase-9, Bax, Fas/FasL (Fas ligand), TRAIL (TNF-related apoptosis-inducing ligand), DR4 (death receptor 4) and DR5 (death receptor 5) were increased in HSC-3 cells, and mRNA and protein expressions of Bcl-2 (B-cell lymphoma 2), Bcl-xL (B-cell lymphoma-extra large), XIAP (X-linked inhibitor of apoptosis protein), cIAP-1 (cellular inhibitor of apoptosis 1), cIAP-2 (cellular inhibitor of apoptosis 2) and survival were decreased. Meanwhile, at the highest concentration of 400 μg/mL, caspase-3, caspase-8, caspase-9, Bax, Fas/FasL, TRAIL, DR4, DR5, and IκB-α expression levels were the highest, and Bcl-2, Bcl-xL, XIAP, cIAP-1, cIAP-2, survival, and NF-κB expression levels were the lowest. These results proved that UDCA could induce apoptosis of HSC-3 cancer cells through caspase activation, and the higher concentration of UDCA had stronger effects in vitro. UDCA might be a good nutrient for oral cancer prevention.

Expression of apoptosis signal-regulating kinase 1 is associated with tight junction protein claudin-6 in cervical carcinoma

In our previous work, apoptosis signal-regulating kinase 1 (ASK1), a member of the mitogen-activated protein kinase (MAPK) kinase family has been proved to be associated with the pro-apoptosis effect of tight junction protein claudin-6 in breast cancer. However, its expression in cervical carcinoma has not been reported. The ASK1 and claudin-6 expression in cervical carcinoma tissues and adjacent non-neoplastic tissues was examined by immunohistochemistry. The mRNA and protein expression of ASK1 and claudin-6 in cervical cancer carcinoma cells was detected by reverse transcription (RT)-PCR and western blot. The expression level of ASK1 was down-regulated in cervical carcinoma tissues compared with the adjacent non-neoplastic tissues and positively correlated with the level of claudin-6 in cervical carcinoma cells and tissues. Our present study reveals that ASK1 protein expression altered between human cervical carcinoma and adjacent non-neoplastic tissues. The expression of ASK1 is correlated with the level of claudin-6 in cervical carcinoma cells and tissues.

Combined TP53 mutation/3p loss correlates with decreased radiosensitivity and increased matrix-metalloproteinase activity in head and neck carcinoma

OBJECTIVE

Patients with head and neck squamous cell carcinoma (HNSCC) containing TP53 mutation and 3p deletion ("double-hit") have poorer prognosis compared to patients with either event alone ("single-hit"). The etiology for worse clinical outcomes in patients with "double-hit" cancers is unclear. We compared radiosensitivity of cell lines containing both TP53 mutations and deletion of Fragile Histidine Triad (FHIT, the gene most commonly associated with 3p deletion) to "single-hit" lines with only TP53 mutation. We compared radiosensitivity in a "single-hit" cell line with TP53 mutation converted to "double-hit" using RNA interference targeting FHIT. Finally, we compared matrixmetalloproteinase-2/9 (MMP-2/9) activity, a previously-established biomarker for tumor aggressiveness, in xenograft tumors derived from these cell lines.

MATERIALS/METHODS

TP53 mutation and FHIT deletion profiles of HNSCC lines were established using Cancer Cell Line Encyclopedia (CCLE). We used RNA-interference to convert a "single-hit" cell line (SCC4) to "double-hit". Cultured cells were examined for radiosensitivity and cisplatin sensitivity. MMP-2/9 activity was evaluated in "double-hit" versus "single-hit" tumors using ratiometric activatable cell-penetrating peptide (RACPP) in tongue (n=17) and flank xenografts (n=4).

RESULTS

Radiotherapy caused greater double-stranded DNA breaks in "single-hit" vs naturally occurring and engineered "double-hit" cells. In-vivo, "double-hit" xenografts demonstrated higher MMP-2/9 activity compared to "single-hit" xenografts (p<0.01). There was no difference in cisplatin sensitivity between the cell lines.

CONCLUSIONS

TP53 mutation combined with FHIT deletion correlates with decreased radiosensitivity in HNC cell lines. Xenograft from "double-hit" cells exhibit increased MMP-2/9 activity. These findings may in part account for the worse clinical outcome seen in patients with HNSCC "double-hit" tumors.

Elevated DNA polymerase iota (Poli) is involved in the acquisition of aggressive phenotypes of human esophageal squamous cell cancer

DNA polymerase iota (Polι) can repair several types of DNA damage but has extremely low fidelity. Previous studies have shown an aberrantly elevated Polι expression in human esophageal squamous cell cancer tissues. However, there were few reports describing the role of Polι in esophageal cancer progression. Based on Real-time PCR assay, we found Polι expression was up-regulated in esophageal cancer tissues compared to adjacent normal tissues and overexpression of Polι was correlated to lymph node metastasis. Clonogenic assay and transwell chamber assay showed that overexpression of Polι had higher clongenic capability and invasive tendency in human esophageal squamous cell cancer cells. Expression of cyclin D1, an important cell cycle regulator, was found to be associated with that of Polι in tissue samples and cancer cells as analyzed by real-time PCR, immunohistochemistry, Western blotting and immunofluorescence assay. Flow cytometry analysis further showed that cell cycle distribution was altered in Polι overexpressing cells. These results indicated that expression of Polι correlates significantly with tumor proliferation and invasion. We conclude that Polι is involved in the degree of aggressiveness of human esophageal squamous cell cancer.

Association of GSTP1 and XRCC1 gene polymorphisms with clinical outcome of advanced non-small cell lung cancer patients with cisplatin-based chemotherapy

We investigated the association between the clinical outcome and GSTP1 and XRCC1 gene polymorphisms in advanced NSCLC patients with cisplatin-based chemotherapy. We prospectively recruited 325 NSCLC patients between January 2010 and January 2014. Genotypes of GSTP1 A313G, XRCC1 Arg194Trp, Arg280His and Arg399Gln were conducted using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) assay. AG and GG genotypes of GSTP1 A313G were correlated with a higher CR + PR when compared with AA genotype. Furthermore, GA and AA genotypes of XRCC1 Arg399Gln were associated with more CR + PR when compared with GG genotype. In the Cox proportional hazards model, GG genotype of GSTP1 A313G was significantly correlated with a longer median survival time when compared with AA genotype, and it is associated with a heavy decreased risk of death from NSCLC. Moreover, GA and AA genotypes of XRCC1 Arg399Gln had a significantly longer median survival time, and GA and AA genotypes were significantly associated with a moderate reduced risk of death from NSCLC. GSTP1 A313G and XRCC1 Arg399Gln gene polymorphisms might influence the response to cisplatin-based chemotherapy and affect the clinical outcome of advanced NSCLC.

HK2 is a radiation resistant and independent negative prognostic factor for patients with locally advanced cervical squamous cell carcinoma

The mechanism by which overexpression of hexokinase 2 (HK2) indicates locally advanced cervical squamous cell carcinoma (LACSCC) with radio-resistance is still unknown despite being an independent biomarker of poor prognosis. Here, we retrospectively analyzed 132 female patients receiving radiotherapy for cervical squamous cell carcinoma including 85 radiation-sensitive cases and 47 radiation-resistant cases. The expression of HK2 was examined by immunohistochemistry. The percentage of high HK2 expression in the radiation-resistant group differed from the radiation-sensitive group with statistical significance (P < 0.001) even if divided into three subgroups including a lower 5-year progression free survival group (PFS) for comparison (P < 0.001). The Kaplan Meier curve analysis showed that there were differences between the two groups (P < 0.001). Therefore, this study proves a close relationship between HK2 expression and radio-resistance. Multivariate Cox regression analysis implied that HK2 was an independent prognostic indicator of cervical squamous carcinoma (HR (95% CI), 2.940 (1.609, 1.609); P = 0.002).

Coexpression of COX-2 and iNOS in Angiogenesis of Superficial Esophageal Squamous Cell Carcinoma

Using immunohistochemical staining, the present study was conducted to examine whether cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS) affect angiogenesis in early-stage esophageal squamous cell carcinoma (ESCC). We also analyzed the correlation between these two factors. Cyclooxygenase 2, iNOS, and angiogenesis in early-stage ESCC are unclear. Using 10 samples of normal squamous epithelium, 7 samples of low-grade intraepithelial neoplasia (LGIN), and 45 samples of superficial esophageal cancer, we observed the expression of COX-2 and iNOS. We then investigated the COX-2 and iNOS immunoreactivity scores and the correlation between COX-2 or iNOS scores and microvessel density (MVD) using CD34 or CD105. The intensity of COX-2 or iNOS expression differed significantly according to histological type (P < 0.001). The scores of COX-2 and iNOS were lowest for normal squamous epithelium, followed in ascending order by LGIN, carcinoma in situ and tumor invading the lamina propria mucosae (M1-M2 cancer); and tumor invading the muscularis mucosa (M3) or deeper cancer. The differences were significant (P < 0.001). Cancers classified M1-M2 (P < 0.01 and P < 0.05, respectively); M3; or deeper cancer (P < 0.01) had significantly higher COX-2 and iNOS scores than normal squamous epithelium. There was a significant correlation between COX-2 and iNOS scores (P < 0.001, rs = 0.51). Correlations between COX-2 score and CD34-positive MVD or CD105-positive MVD were significant (rs = 0.53, P < 0.001; rs = 0.62, P < 0.001, respectively). Inducible nitric oxide synthase score was also significantly correlated with CD34 MVD and CD105 MVD (rs = 0.45, P < 0.001; rs = 0.60, P < 0.001, respectively). Chemoprevention of COX-2 or iNOS activity may blunt the development of ESCC from precancerous lesions.

[Tripartite-motif protein 25 and pyruvate kinase M2 protein expression in non-small cell lung cancer]

OBJECTIVE

To investigate the expression of tripartite-motif protein 25 (TRIM25) and pyruvate kinase M2 (PKM2) protein in non-small cell lung cancer (NSCLC) and explore their role in the occurrence and progression of NSCLC.

METHODS

The expressions of TRIM25 and PKM2 protein were detected in 60 NSCLC specimens and 20 adjacent normal lung tissue (>5 cm from the lesions) with immunofluorescence histochemical method and in 10 fresh specimens of NSCLC with Western blotting. The results were analyzed in relation with the clinicopathological features of the patients.

RESULTS

The positivity rates of TRIM25 expression was 45% in the 60 lung carcinoma specimens, significantly higher than that in the 20 normal lung tissues (10%, P=0.005). TRIM25 protein was expressed in 28.6% of lung adenocarcinoma tissues and in 59.4% of squamous carcinoma tissues (P=0.017). TRIM25 protein expression was positively correlated with the TNM stages and lymph node metastasis of NSCLC (P<0.05). The expressions of PKM2 protein in 60 cases of lung carcinoma was 73.3%,while in 20 cases of normal lung tissues the expressions was 30%(P=0.001). The positivity rates of PKM2 expression differed significantly between lung adenocarcinoma and squamous carcinoma (57.1% vs 87.5%, P=0.008). An inverse correlation was noted between TRIM25 and PKM2 expressions (P=0.026).

CONCLUSION

TRIM25 and PKM2 protein may participate in the occurrence and progression of NSCLC, and their expressions are inversely correlated.

Ectopic expression of protein kinase C-β sensitizes head and neck squamous cell carcinoma to diterpene esters

BACKGROUND

The objective of this study was to examine the effect of specific Protein kinase C (PKC) isoform re-expression in solid malignancies, particularly head and neck squamous cell carcinoma cell lines, and the impact this may have on treatment with known activators of PKC.

MATERIALS AND METHODS

The constitutive expression of PKC isoforms were determined in six head and neck squamous cell carcinoma (SCC) cell lines. Cytotoxicity of the prototypic phorbol ester, 12-O-tetradecanoylphorbol-13-acetate (TPA) and the novel diterpene ester PEP005 was established. Viral transduction to re-express PKCβ isoforms in two of these cell lines was performed, and its effect on the sensitivity to the compounds was quantified.

RESULTS

Tongue and hypopharyngeal SCC cell lines were resistant to both TPA and PEP005, with the concentration required to inhibit growth by 50% (IC50) being >1,000 ng/ml. CAL-27 (tongue SCC) and FaDu (hypopharyngeal SCC) cell lines re-expressing PKCβI and -βII isoforms demonstrated IC50 of 1-5 ng/ml with TPA or PEP005.

CONCLUSION

Re-expression of PKCβ in head and neck SCC cell lines leads to cells one thousand-times more sensitive to the cytotoxic effects of phorbol or diterpene esters in culture. This highlights the importance of the isoform in tumor progression and presents the potential benefit of these compounds in malignancies expressing the protein, and in combination therapy.

Lysyl hydroxylase 2 induces a collagen cross-link switch in tumor stroma

Epithelial tumor metastasis is preceded by an accumulation of collagen cross-links that heighten stromal stiffness and stimulate the invasive properties of tumor cells. However, the biochemical nature of collagen cross-links in cancer is still unclear. Here, we postulated that epithelial tumorigenesis is accompanied by changes in the biochemical type of collagen cross-links. Utilizing resected human lung cancer tissues and a p21CIP1/WAF1-deficient, K-rasG12D-expressing murine metastatic lung cancer model, we showed that, relative to normal lung tissues, tumor stroma contains higher levels of hydroxylysine aldehyde-derived collagen cross-links (HLCCs) and lower levels of lysine aldehyde-derived cross-links (LCCs), which are the predominant types of collagen cross-links in skeletal tissues and soft tissues, respectively. Gain- and loss-of-function studies in tumor cells showed that lysyl hydroxylase 2 (LH2), which hydroxylates telopeptidyl lysine residues on collagen, shifted the tumor stroma toward a high-HLCC, low-LCC state, increased tumor stiffness, and enhanced tumor cell invasion and metastasis. Together, our data indicate that LH2 enhances the metastatic properties of tumor cells and functions as a regulatory switch that controls the relative abundance of biochemically distinct types of collagen cross-links in the tumor stroma.

Serum and Saliva MMP-3 in Patients with OLP and Oral SCC

BACKGROUND

Matrix metalloproteinase-3 (MMP-3) plays a key role in development of cancer. The purpose of this study was to assess MMP-3 in the serum and saliva of patients with oral lichen planus (OLP) and oral squamous cell carcinoma (OSCC).

MATERIALS AND METHODS

Thirty patients with OLP (8 reticular and 22 erosive forms), and 20 patients with OSCC (6 in low stage and 14 in advanced stage), were enrolled in this study, conducted at the Cancer Department, Clinic of Oral Medicine, Tehran University of Medical Sciences. The serum and saliva MMP-3 was assayed by ELISA method. Statistical analysis of the Student's t-test, ANOVA and Pearson correlation coefficient was performed. The mean saliva and serum levels of MMP-3 were significantly higher in patients with OSCC compared with OLP.

RESULTS

The serum and saliva MMP-3 concentrations increased from reticular form of OLP to erosive form of OLP, and increased further to low stage of OSCC and advanced stage of OSCC. Serum MMP-3 correlated significantly with unstimulated (r = 0.310, p = 0.038) and stimulated (r = 0.365, p < 0.026) saliva MMP-3.

CONCLUSION

Serum and saliva MMP-3 levels appear associated with OLP and OSCC.

Association between PLCE1 rs2274223 A > G polymorphism and cancer risk: proof from a meta-analysis

Phospholipase C epsilon 1 (PLCE1) plays an important role in cell growth, differentiation and oncogenesis. An increasing number of individual studies have investigated the association between PLCE1 rs2274223 polymorphism and cancer risk, but the conclusions are inconclusive. To obtain a comprehensive conclusion, we performed a meta-analysis of 22 studies with 13188 cases and 14666 controls. The pooled results indicated that PLCE1 rs2274223 A > G polymorphism was associated with an increased risk of overall cancer (G vs. A: OR = 1.15, 95% CI = 1.06-1.25; GG vs. AA: OR = 1.30, 95% CI = 1.10-1.55; GA vs. AA: OR = 1.18, 95% CI = 1.08-1.30; GG/GA vs. AA: OR = 1.20, 95% CI = 1.08-1.32; GG vs.

GA/AA

OR = 1.22, 95% CI = 1.04-1.42). The stratification analysis showed the polymorphism was significantly associated with an increased risk of esophageal squamous cell carcinoma (ESCC) other than gastric cancer (GC), especially among the subgroups of Asian, high quality score, sample size > 1000 and the studies consistent with Hardy-Weinberg equilibrium (HWE). This meta-analysis demonstrated that PLCE1 rs2274223 A > G polymorphism may be associated with increased susceptibility to cancer, especially for ESCC. However, due to the substantial heterogeneities across the studies, the conclusion might be not conclusive that need more studies to confirm.

RhoC, vascular endothelial growth factor and microvascular density in esophageal squamous cell carcinoma

AIM: To investigate the expression of Ras homolog (Rho)C, vascular endothelial growth factor (VEGF) and CD105 in esophageal squamous cell carcinoma.

METHODS: Semi-quantitative reverse transcriptase polymerase chain reaction, in situ hybridization and immunohistochemical streptavidin-biotin- peroxidase methods were used to detect expression of RhoC mRNA and protein, and VEGF protein in 62 cases with esophageal squamous cell carcinoma, 31 cases with adjacent atypical hyperplastic tissues, and 62 cases with normal esophageal mucosa. CD105 antibody labeling was used to measure microvascular density. Expression levels were compared according to clinicopathologic and patient parameters.

RESULTS: Expression of RhoC mRNA showed a positive correlation with the protein level in esophageal squamous cell carcinoma, as well as with VEGF protein levels. RhoC mRNA expression was mainly located within the cytoplasm of the tumor cells, appearing as blue to purple particles by in situ hybridization. The differences in RhoC mRNA expression in esophageal squamous cell carcinoma, adjacent atypical hyperplasia and normal esophageal mucosa were significant (P < 0.05). The relative expression of RhoC mRNA in cancer tissues with lymph node metastasis was significantly higher than in the tissues without lymph node metastasis (P < 0.05). VEGF protein expression was consistent with microvascular density (t = 25.52, P < 0.05). Positive expression of VEGF protein in esophageal squamous cell carcinoma of different histologic gradings did not differ significantly. Positive expression of VEGF protein in carcinoma tissues with deep infiltration was significantly higher than in tissues with only superficial infiltration (P < 0.05). The positive expression of VEGF protein in cancer tissues with lymph node metastasis was significantly higher than in the tissues without lymph node metastasis (P < 0.05).

CONCLUSION: RhoC protein may upregulate VEGF expression, thereby promoting tumor angiogenesis. RhoC mRNA and protein expression was correlated with metastasis.

MMP-7, MMP-8, and MMP-9 in oral and cutaneous squamous cell carcinomas

OBJECTIVES

Oral squamous cell carcinoma (OSCC) and cutaneous squamous cell carcinoma (CSCC) are epithelial neoplasms, of which OSCC has a worse prognosis. Matrix metalloproteinases (MMPs) are involved in the initiation, invasion, metastasis, and defense of cancer. This study aimed to compare differences in MMP expression in these cancers.

STUDY DESIGN

Sixty-one patients with early-stage (T1-T2 N0 M0) cancers, of which 36 were OSCC and 25 CSCC, were enrolled into this study. Immunohistochemical staining was performed with MMP-7, MMP-8, and MMP-9 antibodies.

RESULTS

MMP-7 expression was stronger in OSCC than in CSCC, mainly in the invasive front. MMP-8 was absent and MMP-9 was mildly expressed in OSCC and CSCC cells. However, MMP-8 and MMP-9 were positive in peritumoral inflammatory cells in both cancers. In addition, MMP-7, MMP-8, and MMP-9 were not associated with the overall survival of patients with OSCC and CSCC patients.

CONCLUSIONS

The increased expression of MMP-7 in the invasive front may partly explain the aggressiveness of OSCC.