Long-Term Survival and Recurrence Patterns in Locally Advanced Esophageal Squamous Cell Carcinoma Patients with Pathologic Complete Response After Neoadjuvant Chemotherapy Followed by Surgery.

BACKGROUND: The higher pathologic complete response (pCR) after neoadjuvant chemoradiotherapy compared with neoadjuvant chemotherapy for locally advanced esophageal squamous cell carcinoma (ESCC) has not translated into significant gains in overall survival. Data on the long-term survival of patients who obtained a pCR after neoadjuvant chemotherapy are scarce. Therefore, this study aimed to evaluate the long-term prognosis and recurrence patterns in these patients. METHODS: The study enrolled patients with locally advanced ESCC after neoadjuvant chemotherapy followed by surgery in the authors' hospital between January 2007 and December 2020. The factors predictive of pCR were analyzed. Furthermore, propensity score-matching was performed for those who did and those who did not have a pCR using 1:5 ratio for a long-term survival analysis. Finally, the survival and recurrence patterns of patients obtaining pCR after neoadjuvant chemotherapy were analyzed. RESULTS: A pCR was achieved for 61 (8.70%) of the 701 patients in the study. Univariate analysis showed that the patients without alcohol drinking had a higher possibility of obtaining a pCR, although multivariate analysis failed to confirm the difference as significant. After propensity score-matching, the 5-year overall survival was 84.50% for the patients who had a pCR and 52.90% for those who did not (p < 0.001). Among the 61 patients with a pCR, 9 patients (14.80%) experienced recurrence, including 6 patients with locoregional recurrence and 3 patients with distant metastasis. CONCLUSION: Advanced ESCC patients with pCR after neoadjuvant chemotherapy had a favorable prognosis, yet some still experienced recurrence, particularly locoregional recurrence. Therefore, for this group of patients, regular follow-up evaluation also is needed.

Hydrogen peroxide is a critical regulator of the hypoxia-induced alterations of store-operated Ca2+ entry into rat pulmonary arterial smooth muscle cells.

To investigate the association between store-operated Ca2+ entry (SOCE) and reactive oxygen species (ROS) during hypoxia, this study determined the changes of transient receptor potential canonical 1 (TRPC1) and Orai1, two candidate proteins for store-operated Ca2+ (SOC) channels and their gate regulator, stromal interaction molecule 1 (STIM1), in a hypoxic environment and their relationship with ROS in pulmonary arterial smooth muscle cells (PASMCs). Exposure to hypoxia caused a transient Ca2+ spike and subsequent Ca2+ plateau of SOCE to be intensified in PASMCs when TRPC1, STIM1, and Orai1 were upregulated. SOCE in cells transfected with specific short hairpin RNA (shRNA) constructs was almost completely eliminated by the knockdown of TRPC1, STIM1, or Orai1 alone and was no longer affected by hypoxia exposure. Hypoxia-induced SOCE enhancement was further strengthened by PEG-SOD but was attenuated by PEG-catalase, with correlated changes to intracellular hydrogen peroxide (H2O2) levels and protein levels of TRPC1, STIM1, and Orai1. Exogenous H2O2 could mimic alterations of the interactions of STIM1 with TRPC1 and Orai1 in hypoxic cells. These findings suggest that TRPC1, STIM1, and Orai1 are essential for the initiation of SOCE in PASMCs. Hypoxia-induced ROS promoted the expression and interaction of the SOC channel molecules and their gate regulator via their converted product, H2O2.