Positive Programmed Cell Death-Ligand 1 Expression Predicts Poor Treatment Outcomes in Esophageal Squamous Cell Carcinoma Patients Receiving Neoadjuvant Chemoradiotherapy.

BACKGROUND: Programmed cell death-ligand 1 (PD-L1) is present in a subgroup of cancer patients who may be favorable targets for immune checkpoint inhibitor therapies. However, the significance of the PD-L1 expression in esophageal squamous cell carcinoma (ESCC) patients receiving neoadjuvant chemoradiotherapy remains unclear. METHODS: By means of PD-L1 immunohistochemistry 22C3 pharmDx assay, we evaluate the PD-L1 expression and its association with clinical outcome in 107 ESCC patients receiving neoadjuvant chemoradiotherapy. RESULTS: Patients with positive PD-L1 expression have significantly lower pathological complete response rates (13% versus 32%; P = 0.036) than those with negative PD-L1 expression. Univariate survival analysis found that positive PD-L1 expression were correlated with poor overall survival (P = 0.004) and inferior disease-free survival (P < 0.001). In a multivariate analysis, positive PD-L1 expression was independently associated with the absence of a pathologically complete response (P = 0.044, hazard ratio: 3.542), worse overall survival (P = 0.006, hazard ratio: 2.017), and inferior disease-free survival (P < 0.001, hazard ratio: 2.516). CONCLUSIONS: For patients with ESCC receiving neoadjuvant chemoradiotherapy, positive PD-L1 expression independently predicts the poor chemoradiotherapy response and worse treatment outcome. Thus, our data suggests that PD-L1 may be an influential biomarker for prognostic classification and for immune checkpoint inhibitor therapies in ESCC patients receiving neoadjuvant chemoradiotherapy.

JMJD3 expression is an independent prognosticator in patients with esophageal squamous cell carcinoma.

BACKGROUND: The Jumonji-domain containing 3 has diverse roles in multiple cancers. Here, we investigated its prognostic significance in esophageal squamous cell carcinoma. METHODS: By using immunohistochemistry, the Jumonji-domain containing 3 expression was examined in 109 surgically resected esophageal squamous cell carcinomas and correlated with treatment outcome. The functional role of Jumonji-domain containing 3 in esophageal squamous cell carcinoma cells was determined by Jumonji-domain containing 3-mediated small interfering ribonucleic acid. RESULTS: Univariate analysis showed that Jumonji-domain containing 3 overexpression was associated with inferior overall survival (P = .004) and disease-free survival (P = .002). In a multivariate comparison, Jumonji-domain containing 3 overexpression remained independently associated with worse overall survival (P = .017, hazard ratio = 1.898) and disease-free survival (P = .011, hazard ratio = 1.901). The 5-year overall and disease-free survival rates were 66% and 58% in patients with a low expression of Jumonji-domain containing 3 and 34% and 27% in patients with overexpression of Jumonji-domain containing 3. Silencing Jumonji-domain containing 3 in esophageal squamous cell carcinoma cells inhibited cell growth rate and bromodeoxyuridine incorporation ability. In contrast, a gain of function of Jumonji-domain containing 3 promoted esophageal squamous cell carcinoma cell proliferation. Furthermore, Jumonji-domain containing 3 expression contributes to Ras/MEK pathway. CONCLUSION: Jumonji-domain containing 3 overexpression was independently associated with poor prognosis in patients with esophageal squamous cell carcinoma. In vitro, Jumonji-domain containing 3 expression regulated esophageal squamous cell carcinoma cell growth. These results may further elucidate the role of Jumonji-domain containing 3 in esophageal squamous cell carcinoma and provide a potential new therapeutic approach for patients with esophageal squamous cell carcinoma.

SIRT1 overexpression is an independent prognosticator for patients with esophageal squamous cell carcinoma.

BACKGROUND: Sirtuin 1 (SIRT1) regulates DNA repair and metabolism by deacetylating target proteins. SIRT1 may be oncogenic because its overexpression has been detected in many cancers. The aim of the present study was to clarify the prognostic role of SIRT1 in patients with esophageal squamous cell carcinoma (ESCC) and evaluate the effect of SIRT1 inhibitor in vitro. METHODS: The expression of SIRT1 was evaluated immunohistochemically in 155 surgically resected ESCC and the staining results were evaluated semiquantitatively by the Immunoreactive Scoring System. The clinical features and treatment outcome were analyzed. The effect of SIRT1 inhibitor, SIRT 1 inhibitor IV, (S)-35, was investigated in vitro on ESCC cell lines. RESULTS: The expression of SIRT1 on ESCC did not correlate with age, gender, tumor location, stage, T classification, N classification, surgical margin or histology. Univariate analysis showed that SIRT1 overexpression was associated with inferior overall survival (P = 0.004) and disease-free survival (P = 0.004). In multivariate comparison, SIRT1 overexpression remained independently associated with worse overall survival (P = 0.009, hazard ratio = 1.776) and disease-free survival (P = 0.017, hazard ratio = 1.642). In cell lines, SIRT1 inhibitor inhibited ESCC growth. CONCLUSIONS: Our study suggests that SIRT1 overexpression is an independent prognosticator for patients with ESCC and the SIRT1 inhibitor suppressed cell proliferation of ESCC cell lines. Our findings suggest that inhibition of SIRT1 signaling may be a promising novel target for ESCC.

The Prognostic Significance of Histone Demethylase UTX in Esophageal Squamous Cell Carcinoma.

The dysregulation of the ubiquitously transcribed TPR gene on the X chromosome (UTX) has been reported to be involved in the oncogenesis of several types of cancers. However, the expression and significance of UTX in esophageal squamous cell carcinoma (ESCC) remains largely undetermined. Immunohistochemistry was performed in 106 ESCC patients, and correlated with clinicopathological features and survival. The functional role of UTX in ESCC cells was determined by UTX-mediated siRNA. Univariate analyses showed that high UTX expression was associated with superior overall survival (OS, p = 0.011) and disease-free survival (DFS, p = 0.01). UTX overexpression was an independent prognosticator in multivariate analysis for OS (p = 0.013, hazard ratio = 1.996) and DFS (p = 0.009, hazard ratio = 1.972). The 5-year OS rates were 39% and 61% in patients with low expression and high expression of UTX, respectively. Inhibition of endogenous UTX in ESCC cells increased cell viability and BrdU incorporation, and decreased the expression of epithelial marker E-cadherin. Immunohistochemically, UTX expression was also positively correlated with E-cadherin expression. High UTX expression is independently associated with a better prognosis in patients with ESCC and downregulation of UTX increases ESCC cell growth and decreases E-cadherin expression. Our results suggest that UTX may be a novel therapeutic target for patients with ESCC.

An actin-binding protein ESPN is an independent prognosticator and regulates cell growth for esophageal squamous cell carcinoma.

BACKGROUND: ESPN (Espin), an actin filament-binding protein, plays an important role in regulating the organization, dimensions, dynamics, and signaling capacities of the actin filament-rich, microvillus-type specializations that mediate sensory transduction in various mechanosensory and chemosensory cells. Recent few studies show that ESPN regulates metastasis and cell proliferation in melanoma. However, the significance of ESPN in other cancers such as esophageal squamous cell carcinoma (ESCC) remains largely unknown. METHODS: Immunohistochemistry was performed in 169 patients with ESCC and correlated with clinicopathological features and survival. The functional role of ESPN in ESCC cells was determined by ESPN-mediated siRNA. RESULTS: Univariate analyses showed that high ESPN expression was associated with inferior overall survival (P = 0.005) and disease-free survival (P = 0.035). High ESPN expression was an independent prognosticator in multivariate analysis for overall survival (P = 0.009, hazard ratio = 1.688) and disease-free survival (P = 0.049, hazard ratio = 1.451). The 5-year overall survival rates were 30% and 54% in patients with high and low expression of ESPN, respectively. Inhibition of endogenous ESPN in ESCC cells decreased ESCC growth by reducing cell proliferating rates. CONCLUSIONS: High ESPN expression is independently associated with poor prognosis in patients with ESCC and downregulation of ESPN inhibits ESCC cell growth. Our results suggest that ESPN may be a novel therapeutic target for patients with ESCC.

Prognostic significance and function of mammalian target of rapamycin in tongue squamous cell carcinoma.

Despite improvement in preoperative imaging, surgical technique, and adjuvant therapy, the prognosis of patients with tongue squamous cell carcinoma (SCC) is still unsatisfactory. The mammalian target of rapamycin (mTOR) play a key role in the regulation of tumor cell proliferation and survival. However, the significance of mTOR on the prognosis of tongue SCC remains largely undefined. In the present study, immunohistochemistry was performed to evaluate the expression of phosphorylated mTOR (p-mTOR) in 160 surgically resected tongue SCC, and correlated with survival. Univariate analysis revealed that p-mTOR overexpression (P = 0.006) was associated with inferior overall survival. In multivariate comparison, p-mTOR overexpression (P = 0.002, hazard ratio = 2.082) remained independently associated with worse overall survival. In vitro study, tongue cancer cells treated with everolimus, the specific mTOR inhibitor, or transfected with mTOR-mediated siRNAs dramatically attenuated the abilities of cell proliferation by MTT and BrdU assays. In 4-NQO-induced tongue cancer murine model, mTOR inhibitors significantly decreased the incidence of tongue SCC. In conclusion, p-mTOR overexpression was independently associated with poor prognosis of patients with tongue SCC. In vitro and vivo, mTOR inhibition showed the promising activity in tongue SCC. Our results suggest that inhibition of mTOR signaling pathway may be a novel therapeutic target for tongue SCC.

Angiotensin II type I receptor (AT1R) is an independent prognosticator of esophageal squamous cell carcinoma and promotes cells proliferation via mTOR activation.

BACKGROUND: The aim of this study was to investigate the effects of the angiotensin II/ angiotensin II type I receptor (AT1R) and angiotensin II type II receptor (AT2R) signaling pathway in esophageal squamous cell carcinoma (ESCC). METHODS: Immunohistochemistry was performed to evaluate the expression levels of AT1R and AT2R in tissues from 152 surgically resected ESCC patients, and those expression levels were then correlated with treatment outcomes. The angiotensin II/AT1R/AT2R signaling pathway and its biological effects in the context of ESCC were investigated in vitro and in vivo. RESULTS: In human samples, AT1R overexpression was univariately associated with inferior overall survival and remained multivariately independent (hazard ratio=1.812). In vitro, angiotensin II stimulated the growth of ESCC cells in a dose-dependent manner. Treatment with irbesartan or AT1R-RNAi knockdown but not treatment with PD123319 significantly decreased the level of angiotensin II-induced ESCC cell proliferation. Angiotensin II also caused mTOR activation in a dose-dependent manner, and everolimus or mTOR-RNAi knockdown significantly suppressed the level of angiotensin II-induced ESCC cell proliferation. Furthermore, AT1R-RNAi knockdown suppressed the activation of mTOR. Clinically, AT1R expression was also correlated with phosphorylated mTOR expression. In a xenograft model, local angiotensin II injection enhanced tumor growth, and this effect could be decreased by treatment with irbesartan or everolimus. In a 4-NQO-induced-ESCC murine model, irbesartan significantly decreased the incidence of esophageal tumor. CONCLUSIONS: These findings suggest that AT1R overexpression is an independent adverse prognosticator for patients with ESCC and that angiotensin II/AT1R signaling stimulates ESCC growth, in part through mTOR activation.

Phosphorylated p70S6K expression is an independent prognosticator for patients with esophageal squamous cell carcinoma.

BACKGROUND: Although marked improvements have been made in surgical technique and chemoradiotherapy, the prognosis for patients with esophageal squamous cell carcinoma (ESCC) is still unsatisfactory. The mammalian target of rapamycin (mTOR) and its downstream signaling, p70 ribosomal S6 protein kinase (p70S6K) and eukaryotic translation initiation factor 4E (eIF4E)-binding protein 1 (4E-BP1), seem to play central roles in the regulation of cancer cell proliferation and survival. The significance of mTOR and its downstream targets, p70S6K and 4E-BP1, on the prognosis of ESCC remains uncertain, but this pathway is of particular concern because effective inhibitors are already available. METHODS: Immunohistochemistry performed to evaluate the expression of phosphorylated mTOR (p-mTOR), phosphorylated p70S6K (p-p70S6K), phosphorylated 4E-binding protein 1 (p-4E-BP1), and Ki-67 using 105 surgically resected ESCC correlated with treatment outcome. The effect of the mTOR signaling pathway inhibitor everolimus on ESCC cell lines were investigated in vitro by the 3-(4.5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and in vivo by a nude mouse xenograft model. RESULTS: Univariate analysis showed that p-mTOR overexpression (P = .022), p-p70S6K overexpression (P = .002), and Ki-67 labeling index >50% (P = .045) were associated with inferior overall survival (OS). In a multivariate comparison, p-p70S6K overexpression (P = .001; hazard ratio, 2.247) remained independently associated with worse OS. In cell lines and the xenograft model, everolimus significantly inhibited ESCC growth. CONCLUSION: Overexpression of p-p70S6K is associated independently with a poor prognosis among patients with ESCC. The mTOR signaling pathway inhibitor everolimus can inhibit ESCC growth in vitro and in vivo. Our findings suggest that inhibition of mTOR signaling pathway may be a promising novel target for ESCC.

Zoledronic acid-induced cytotoxicity through endoplasmic reticulum stress triggered REDD1-mTOR pathway in breast cancer cells.

BACKGROUND: Zoledronic acid (ZOL) used for the prevention/treatment of osteopathic complications has been reported to have antitumor effects in breast cancer treatment. However, little is known about the exact molecular mechanisms for antitumor actions of ZOL. In this study, two breast cancer cell lines were used to investigate the antitumor efficacy of ZOL and the underlying molecular mechanisms. RESULTS: The growth of two breast cancer cell lines was markedly decreased following treatment with ZOL. Compared with MCF-7 cells, MDA-MB-231 cells were more sensitive to ZOL treatment. Western blot analysis showed that the inhibitory effect of zoledronic acid on growth was related to the extent of inhibition of phosphorylated-protein kinase B (p-AKT), and phosphorylated-mammalian target of rapamycin (p-mTOR). Moreover, the expression of the stress-responsive protein regulated in development and DNA damage response 1 (REDD1), an inhibitor of mTOR, was induced markedly to various degrees in different breast cancer cell lines after ZOL treatment. Interestingly, by examining the upstream signaling pathway of REDD1, we found that ZOL can induce endoplasmic reticulum stress responses through activating the protein kinase R (PKR)-related ER kinase-eukaryotic initiation factor 2 alpha-CCAAT/enhancer binding protein homologous protein (PERK-eIF2α-CHOP) pathway. CONCLUSION: Taken together, these results indicated that ZOL-induced cell death was caused by endoplasmic reticulum stress activating PERK-eIF2α-CHOP pathway to induce REDD1 expression and inhibit the mTOR pathway.