Response evaluation with endoscopic ultrasound and computed tomography in esophageal squamous cell carcinoma treated by definitive chemoradiotherapy

Dysregulation of SOX17/NRF2 axis confers chemoradiotherapy resistance and emerges as a novel therapeutic target in esophageal squamous cell carcinoma

Background

Esophageal squamous cell carcinoma (ESCC) is the sixth leading cause of cancer-associated death worldwide with a dismal overall 5-year survival rate of less than 20%. The standard first-line therapy for advanced ESCC is concomitant chemo-radiation therapy (CCRT); however, patients usually develop resistance, resulting in unfavorable outcomes. Therefore, it is urgent to identify the mechanisms underlying CCRT resistance and develop effective treatment strategies.

Methods

Patients’ endoscopic biopsy tumor tissues obtained before CCRT treatment were used to perform RNA-seq and GSEA analysis. Immunohistochemical (IHC) staining, chromatin immunoprecipitation (ChIP), and promoter reporter analyses were conducted to investigate the relationship between SOX17 and NRF2. Xenograft mouse models were used to study the role of SOX17/NRF2 axis in tumor growth and the efficacy of carboxymethyl cellulose-coated zero-valent-iron (ZVI@CMC).

Results

In this study, a notable gene expression signature associated with NRF2 activation was observed in the poor CCRT responders. Further, IHC staining of endoscopic biopsy of 164 ESCC patients revealed an inverse correlation between NRF2 and SOX17, a tumor-suppressive transcription factor with low expression in ESCC due to promoter hypermethylation. Using ChIP and promoter reporter analyses, we demonstrated that SOX17 was a novel upstream transcriptional suppressor of NRF2. In particular, SOX17^low/NRF2^high nuclear level significantly correlated with poor CCRT response and poor survival, indicating that the dysregulation of SOX17/NRF2 axis played a pivotal role in CCRT resistance and tumor progression. Notably, the in-house developed nanoparticle ZVI@CMC functioned as an inhibitor of DNA methyltransferases to restore expression of SOX17 that downregulated NRF2, thereby overcoming the resistance in ESCC. Additionally, the combination of ZVI@CMC with radiation treatment significantly augmented anticancer efficacy to inhibit tumor growth in CCRT resistant cancer.

Conclusion

This study identifies a novel SOX17^low/NRF2^high signature in ESCC patients with poor prognosis, recognizes SOX17 as a transcriptional repressor of NRF2, and provides a promising strategy targeting SOX17/NRF2 axis to overcome resistance.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12929-022-00873-4.

Radiation dose escalation can improve local disease control and survival among esophageal cancer patients with large primary tumor volume receiving definitive chemoradiotherapy

BACKGROUND

This study aimed to investigate the correlation between primary tumor volume and cancer failure patterns in esophageal squamous cell carcinoma (ESCC) treated with definitive concurrent chemoradiotherapy (CCRT) and examine whether increasing radiation dose can improve the outcome.

METHODS

We retrospectively reviewed 124 patients with stage III ESCC treated by definitive CCRT. The primary tumor volume calculated from the radiotherapy planning computed tomography scans was correlated to treatment response, time to disease progression, and overall survival. We further analyzed whether a higher radiation dose correlated with better disease control and patient survival.

RESULTS

Patients with poor CCRT response had a larger primary tumor volume than those with good response (97.9 vs 64.3 cm3, P = 0.032). The optimal cutoff value to predict CCRT response was 55.3 cm3. Large primary tumor volume (≥ 55.3 cm3) correlated with shorter time to tumor progression in the esophagus (13.6 vs 48.6 months, P = 0.033) compared with small tumor volume (< 55.3 cm3). For the large esophageal tumors (≥ 55.3 cm3), radiation dose > 60 gray significantly prolonged the time to tumor progression in esophagus (20.3 vs 10.1 months, P = 0.036) and overall survival (12.2 vs 8.0 months, P = 0.030), compared with dose ≤ 60 gray. In contrast, higher radiation dose did not benefit local disease control or overall survival in the small esophageal tumors (< 55.3 cm3).

CONCLUSION

Large primary tumor volume correlates with poor local control and overall survival in ESCC treated with definitive CCRT. Radiation dose > 60 gray can improve the outcomes in patients with large primary tumor. Further prospective dose escalation trials are warranted.

SOX17 overexpression sensitizes chemoradiation response in esophageal cancer by transcriptional down-regulation of DNA repair and damage response genes

Background

Prognosis of esophageal squamous cell carcinoma (ESCC) patients is poor and the concurrent chemoradiation therapy (CCRT) provided to ESCC patients often failed due to resistance. Therefore, development of biomarkers for predicting CCRT response is immensely important. In this study, we evaluated the predicting value of SRY (sex determining region Y)-box 17 (SOX17) protein during CCRT and its dysregulation of transcriptional targets in CCRT resistance in ESCC.

Methods

Pyrosequencing methylation, RT-qPCR and immunohistochemistry assays were performed to examine the DNA methylation, mRNA expression and protein expression levels of SOX17 in endoscopic biopsy from a total of 70 ESCC patients received CCRT. Cell proliferation, clonogenic survival and xenograft growth were used to confirm the sensitization of ESCC cell line KYSE510 in response to cisplatin, radiation or CCRT treatment by SOX17 overexpression in vitro and in vivo. Luciferase activity, RT-qPCR and ChIP-qPCR assays were conducted to examine transcription regulation of SOX17 in KYSE510 parental, KYSE510 radio-resistant cells and their derived xenografts.

Results

High DNA methylation coincided with low mRNA and protein expression levels of SOX17 in pre-treatment endoscopic biopsy from ESCC patients with poor CCRT response. SOX17 protein expression exhibited a good prediction performance in discriminating poor CCRT responders from good responder. Overexpression of SOX17 sensitized KYSE510 radio-resistant cells to cisplatin, radiation or CCRT treatment in cell and xenograft models. Importantly, SOX17 transcriptionally down-regulated DNA repair and damage response-related genes including BRCA1, BRCA2, RAD51, KU80 DNAPK, p21, SIRT1, NFAT5 and REV3L in KYSE510 radio-resistant cells to achieve the sensitization effect to anti-cancer treatment. Low expression of BRCA1, DNAPK, p21, RAD51 and SIRT1 was confirmed in SOX17 sensitized xenograft tissues derived from radio-resistant ESCC cells.

Conclusions

Our study reveals a novel mechanism by which SOX17 transcriptionally inactivates DNA repair and damage response-related genes to sensitize ESCC cell or xenograft to CCRT treatment. In addition, we establish a proof-of-concept CCRT prediction biomarker using SOX17 immunohistochemical staining in pre-treatment endoscopic biopsies to identify ESCC patients who are at high risk of CCRT failure and need intensive care.

Electronic supplementary material

The online version of this article (10.1186/s12929-019-0510-4) contains supplementary material, which is available to authorized users.

The in vivo tissue effect of endoscopic balloon-based radiofrequency ablation in treating esophageal squamous cell neoplasia

Background

Endoscopic radiofrequency ablation (RFA) is a rapidly evolving therapeutic modality for early flat esophageal squamous cell neoplasms (ESCNs). However, the in vivo tissue effects of RFA on the esophageal wall are uncertain.

Methods

We prospectively enrolled eight patients with flat-type early ESCNs who were treated with balloon-based RFA. We evaluated the in vivo tissue effect on the esophagus using endoscopic ultrasound (EUS) and the histology of retrieved coagulum.

Results

The mean tumor length was 6.1 cm, and six of the eight patients achieved a complete response after primary RFA. Real-time evaluation of the tissue effect showed that the mucosa and submucosal layer were more edematous and thicker after RFA than before the procedure (mean 4.89 vs. 2.04 mm, p<.001), suggesting that the thermal effect of RFA may injure the submucosa. Histological evaluation of retrieved coagulum showed a severe cauterization (burning) effect with extensive cell necrosis; however, four cases had some residual viable neoplastic cells. Even though there were viable cells in the sloughed coagulum, half of the patients still achieved complete remission after RFA.

Conclusions

Our findings suggest that the thermal effect of RFA may injure the submucosal layer and enable neoplastic epithelium to slough off without "burning."

MiR-193a-5p/ERBB2 act as concurrent chemoradiation therapy response indicator of esophageal squamous cell carcinoma

Concurrent chemoradiation therapy (CCRT) is the predominant treatment in esophageal cancer, however resistance to therapy and tumor recurrence are exceedingly common. Elevated ERBB2/Her2 may be at least partially responsible for both the high rates of recurrence and resistance to CCRT. This receptor tyrosine kinase is upregulated in 10–20% of esophageal squamous cell carcinoma (ESCC) tissues, and amplification of ERBB2 has been correlated with poor prognosis in esophageal cancer. Tissues from 131 ESCC patients, along with cell and animal models of the disease were used to probe the underlying mechanisms by which ERBB2 upregulation occurs and causes negative outcomes in ESCC. We found that overexpression of ERBB2 inhibited radiosensitivity in vitro. Furthermore, miR-193a-5p reduced ERBB2 expression by directly targeting the 3′UTR. Increased miR-193a-5p enhanced radiosensitivity and inhibited tumorigenesis in vitro and in vivo. Additionally, low miR-193a-5p expression correlated with poor prognosis in ESCC patients, and ESCC patients with good CCRT response exhibited higher miR-193a-5p expression. Our data suggest that patients with high miR-193a-5p will likely benefit from CCRT treatment alone, however a combination of CCRT with Herceptin may be beneficial for patients with low miR-193a-5p expression.

A six-CpG panel with DNA methylation biomarkers predicting treatment response of chemoradiation in esophageal squamous cell carcinoma

BACKGROUND

Prognosis of esophageal squamous cell carcinoma (ESCC) patients remains poor, and the chemoradiotherapy (CRT) applied to ESCC patients often failed. Therefore, development of biomarkers to predict CRT response is immensely important for choosing the best treatment strategy of an individual patient.

METHODS

The methylation array and pyrosequencing methylation assay were performed in pre-treatment endoscopic biopsies to identify probes with differential CpG methylation levels between good and poor CRT responders in a cohort of 12 ESCC patients. Receiver operating characteristic curves and multivariate logistic regressions were conducted to build the risk score equation of selected CpG probes in another cohort of 91 ESCC patients to predict CRT response. Kaplan-Meier analysis was used to estimate progression-free survival or time-to-progression of patients predicted with good and poor CRT responses.

RESULTS

Nine differentially methylated CpG probes were identified to be associated with CRT response. A risk score equation comprising six CpG probes located in IFNGR2, KCNK4, NOTCH4, NPY, PAX6, and SOX17 genes were built. The risk score was derived from the sum of each probe multiplied by its corresponding coefficient. Such a risk score has a good prediction performance in discriminating poor CRT responders from good responders (AUC: 0.930). Moreover, poor CRT responders predicted by risk score significantly had poorer prognosis in terms of shorter progression-free survival and time-to-progression (p = 0.004-0.008).

CONCLUSION

We established a proof-of-concept CRT response prediction panel consisting of six-CpG methylation biomarkers in identifying ESCC patients who are at high risk of CRT failure and need intensive care.

Comparison of cisplatinum/paclitaxel with cisplatinum/5-fluorouracil as first-line therapy for nonsurgical locally advanced esophageal squamous cell carcinoma patients

Background

To retrospectively evaluate the efficacy and toxicity of definitive concurrent chemoradiotherapy (dCRT) with cisplatinum/paclitaxel versus cisplatinum/5-fluorouracil in patients with locally advanced esophageal squamous cell carcinoma (ESCC) who received nonsurgical treatment.

Methods

This study retrospectively evaluated 202 patients with locally advanced ESCC treated at Shandong Cancer Hospital between January 2009 and December 2013. All the patients initially received dCRT, including platinum and paclitaxel or 5-fluorouracil, with concurrent 1.8 or 2 Gy/fraction radiation (total dose, 54–60 Gy). The patient population was divided into two treatment groups: 105 patients who received the cisplatinum/paclitaxel regimen were allocated to group A, and 97 patients who received the cisplatinum/5-fluorouracil regimen were allocated to group B. We compared the progression-free survival (PFS) and overall survival (OS) by various clinical variables, including prior treatment characteristics, major toxicities (mainly in grade 3 and 4 hematological), and response to dCRT. We used the receiver operating curve analysis to determine the optimal cutoff value of clinical stage and radiation dose. The Kaplan–Meier method was used for survival comparison and Cox regression for multivariate analysis.

Results

Median PFS and OS in group A were significantly better compared with group B (median PFS, 15.9 versus 13.0 months, P=0.016 and median OS, 33.9 versus 23.1 months, P=0.014, respectively). The 1- and 2-year survival rates of the two groups were 82.9% versus 76.3%, and 61.9% versus 47.6%, respectively. The complete response and response rate were 17.1% versus 7.2% (P=0.032) and 52.4% versus 30.9% (P=0.042) in group A and B, respectively. Meanwhile, group B was associated with a significantly lower rate of grade 3/4 overall toxicity than group A (P=0.039).

Conclusion

Our data showed that patients with locally advanced ESCC in group A had longer PFS and OS compared with group B. Cisplatinum/paclitaxel can be considered a good candidate chemotherapy regimen for patients with locally advanced ESCC who are being treated with nonsurgical therapy.