Daniel King Hung Tong

Current Management of Cervical Esophageal Cancer

BackgroundPharyngo-laryngo-esophagectomy (PLE) has been regarded as a standard treatment for cervical esophageal cancer, but the morbidity and mortality rates associated with PLE are substantial. Chemoradiation (CTRT) is widely used to treat esophageal cancer; however, its role in managing cervical esophageal cancer has not been fully elucidated. It was hypothesized that up-front CTRT could be an effective alternative treatment option to PLE. The purpose of this study was to compare the outcomes of patients with cervical esophageal cancer treated with these two methods.MethodsPatients with cervical esophageal cancer from 1995 to 2008 were studied. Three main groups were identified: those treated with PLE, those managed with up-front concurrent chemoradiation, and those not suitable for either PLE or chemoradiation but to whom palliative treatment was offered. The demographics, management strategies, and outcomes of these patients were studied and analyzed.ResultsA total of 107 patients were studied: 87 (81.3%) were men, and the median age was 64xa0years (range 17–92xa0years). There were 62 patients who underwent PLE as the primary treatment, 21 had up-front chemoradiation, and the others had palliative treatment. In the PLE group, curative resection was achieved in 37 (59.7%) patients, 20 of whom had either adjuvant chemoradiation or radiotherapy. The hospital mortality rate was 7.1%. In the chemoradiation group, 10 (47.6%) had tumor down-staging, 6 of whom achieved a clinically complete response. Among the 11 patients with poor response, 5 required salvage PLE for palliation. Chemoradiation-associated morbidities included oral mucositis, bilateral vocal cord palsy, esophageal stricture, carotid artery blowout, and permanent hypothyroidism and hypoparathyroidism. The median survival durations of patients in the PLE and chemoradiation groups were 20 and 25xa0months respectively (Pxa0=xa00.39).ConclusionsUp-front chemoradiation can be an alternative therapeutic strategy to PLE. However, this method is not without drawbacks. A significant proportion also requires salvage surgery. Both PLE and chemoradiation have significant curative as well as palliative role in the management of cervical esophageal cancer and treatment should be individualized.

Histological Regression of Squamous Esophageal Carcinoma Assessed by Percentage of Residual Viable Cells after Neoadjuvant Chemoradiation is an Important Prognostic Factor

BackgroundWhether the TNM staging system is applicable after neoadjuvant chemoradiation in esophageal cancer is controversial. The aim of this study was to evaluate the prognostic value of histopathological regression of the primary tumor in postchemoradiated patients.Materials and MethodsThe pretherapeutic and pathological ypTNM stages of patients who have had neoadjuvant chemoradiation followed by esophagectomy were analyzed. The percentage of residual viable cells of the primary tumor (ypV) and other clinicopathological factors were tested for their prognostic value.ResultsOf 175 recruited patients, 55 (31.4%) achieved pathological complete response. The median survival of these 55 patients was significantly longer than those with other disease stages (124.8 vs 21.1xa0months) (Pxa0<xa0.001). Gender, ypT, ypN, ypTNM, and ypV stage were significant prognostic factors in univariate analysis. In patients without nodal metastases, the median survival in patients with residual viable cells in the primary tumor (ypV+) was 24.6xa0months, compared with that of 124.8xa0months in those with no viable cells (ypV0) (Pxa0=xa0.043). In those who had nodal metastases, the median survival of patients with ypV0 and ypV+xa0were 21.2xa0months and 17.4xa0months respectively (Pxa0=xa0.37). Cox regression analysis showed that male gender, high percentage of residual viable cells (ypV), and positive nodal status (ypN1) were independent predictors of poor prognosis.ConclusionsIn patients who underwent neoadjuvant chemoradiation therapy, histopathological regression of the primary tumor indicated by percentage of residual viable cells is an important prognostic factor in addition to nodal status and gender.

Nuclear Localization of DNAJB6 Is Associated With Survival of Patients With Esophageal Cancer and Reduces AKT Signaling and Proliferation of Cancer Cells

BACKGROUND & AIMSnThe DnaJ (Hsp40) homolog, subfamily B, member 6 (DNAJB6) is part of a family of proteins that regulates chaperone activities. One of its isoforms, DNAJB6a, contains a nuclear localization signal and regulates β-catenin signaling during breast cancer development. We investigated the role of DNAJB6 in the pathogenesis of esophageal squamous cell carcinoma (ESCC).nnnMETHODSnWe performed immunohistochemical analyses of primary ESCC samples and lymph node metastases from a cohort of 160 patients who underwent esophagectomy with no preoperative chemoradiotherapy at Hong Kong Queen Mary Hospital. Data were collected on patient outcomes over a median time of 12.1 ± 2.9 months. Retrospective survival association analyses were performed. Wild-type and mutant forms of DNAJB6a were overexpressed in cancer cell lines (KYSE510, KYSE 30TSI, KYSE140, and KYSE70TS), which were analyzed in proliferation and immunoblot assays, or injected subcutaneously into nude mice. Levels of DNAJB6 were knocked down in ESCC cell lines (KYSE450 and T.Tn), immortalized normal esophageal epithelial cell lines (NE3 and NE083), and other cells with short hairpin RNAs, or by genome engineering. Bimolecular fluorescence complementation was used to study interactions between proteins in living cells.nnnRESULTSnIn primary ESCC samples, patients whose tumors had high nuclear levels of DNAJB6 had longer overall survival times (19.2 ± 1.8 months; 95% confidence interval [CI], 15.6-22.8 mo) than patients whose tumors had low nuclear levels of DNAJB6 (12.6 ± 1.4 mo; 95% CI, 9.8-15.4 mo; Pxa0= .004, log-rank test). Based on Cox regression analysis, patients whose tumors had high nuclear levels of DNAJB6 had a lower risk of death than patients with low levels (hazard ratio, 0.562; 95% CI, 0.379-0.834; Pxa0= .004). Based on log-rank analysis and Cox regression analysis, the combination of the nuclear level of DNAJB6 and the presence of lymph node metastases at diagnosis could be used to stratify patients into groups with good or bad outcomes (P < .0005 for both analyses). There was a negative association between the nuclear level of DNAJB6 and the presence of lymph node metastases (Pxa0= .022; Pearson χ(2) test). Cancer cell lines that overexpressed DNAJB6a formed tumors more slowly in nude mice than control cells or cells that expressed a mutant form of DNAJB6a that did not localize to the nucleus. DNAJB6 knockdown in cancer cell lines promoted their growth as xenograft tumors in mice. A motif of histidine, proline, and aspartic acid in the J domain of DNAJB6a was required for its tumor-suppressive effects and signaling via AKT1. Loss of DNAJB6a resulted in up-regulation of AKT signaling in cancer cell lines and immortalized esophageal epithelial cells. Expression of a constitutively active form of AKT1 restored proliferation to tumor cells that overexpressed DNAJB6a, and DNAJB6a formed a complex with AKT1 in living cells. The expression of DNAJB6a reduced the sensitivity of ESCC to AKT inhibitors; the expression level of DNAJB6a affected AKT signaling in multiple cancer cell lines.nnnCONCLUSIONSnNuclear localization of DNAJB6 is associated with longer survival times of patients with ESCC. DNAJB6a reduces AKT signaling, and DNAJB6 expression in cancer cells reduces their proliferation and growth of xenograft tumors in mice. DNAJB6a might be developed as a biomarker for progression of ESCC.

Overexpression of microRNA-1288 in oesophageal squamous cell carcinoma

PURPOSEnThis study aims to examine the expression profiles miR-1288 in oesophageal squamous cell carcinoma (ESCC). The cellular implications and target interactions of ESCC cells following miR-1288 overexpression was also examined.nnnMETHODSnIn total, 120 oesophageal tissues (90 primary ESCCs and 30 non-neoplastic tissues) were recruited for miR-1288 expression analysis using qRT-PCR. An exogenous miR-1288 mimic and its inhibitor were used to explore the in-vitro effects of miR-1288 on ESCC cells by performing cell proliferation, colony formation, cell invasion and migration assays. Localisation and modulatory changes of various miR-1288 regulated proteins such as FOXO1, p53, TAB3, BCL2 and kRAS was examined using immunofluorescence and western blot.nnnRESULTSnOverexpression of miR-1288 was more often noted in ESCC tissues when compared to non-neoplastic oesophageal tissues. High expression was often noted in high grade carcinomas and with metastases. Patients with high levels of miR-1288 expression showed a slightly better survival compared to patients with low miR-1288 levels. Furthermore, overexpression of miR-1288 showed increased cell proliferation and colony formation, improved cell migration and enhanced cell invasion properties in ESCC cells. In addition, miR-1288 overexpression in ESCC cells showed repression of cytoplasmic tumour suppressor FOXO1 protein expression. Inversely, inhibition of miR-1288 expression exhibited remarkable upregulation of FOXO1 protein, while expressions of other tested proteins remain unchanged.nnnCONCLUSIONSnUp regulation of miR-1288 expression in ESCC tissues and miR-1288 induced oncogenic features of ESCC cells in-vitro indicates the oncogenic roles of miR-1288 in ESCCs. Overexpression of miR-1288 play a key role in the pathogenesis of ESCCs and its modulation may have potential therapeutic value in patients with ESCC.

A Versatile Orthotopic Nude Mouse Model for Study of Esophageal Squamous Cell Carcinoma

Increasing evidence indicates tumor-stromal interactions play a crucial role in cancer. An in vivo esophageal squamous cell carcinoma (ESCC) orthotopic animal model was developed with bioluminescence imaging established with a real-time monitoring platform for functional and signaling investigation of tumor-stromal interactions. The model was produced by injection of luciferase-labelled ESCC cells into the intraesophageal wall of nude mice. Histological examination indicates this orthotopic model is highly reproducible with 100% tumorigenesis among the four ESCC cell lines tested. This new model recapitulates many clinical and pathological properties of human ESCC, including esophageal luminal stricture by squamous cell carcinoma with nodular tumor growth, adventitia invasion, lymphovascular invasion, and perineural infiltration. It was tested using an AKT shRNA knockdown of ESCC cell lines and the in vivo tumor suppressive effects of AKT knockdown were observed. In conclusion, this ESCC orthotopic mouse model allows investigation of gene functions of cancer cells in a more natural tumor microenvironment and has advantages over previous established models. It provides a versatile platform with potential application for metastasis and therapeutic regimen testing.

Corrigendum to "A Versatile Orthotopic Nude Mouse Model for Study of Esophageal Squamous Cell Carcinoma".

[This corrects the article DOI: 10.1155/2015/910715.].