High TLR4 expression predicts a poor prognosis after esophagectomy for advanced thoracic esophageal squamous cell carcinoma

Sex differences in survival following surgery for esophageal cancer: A systematic review and meta-analysis

The impact of sex on the prognosis of patients with esophageal cancer remains unclear. Evidence supports that sex- based disparities in esophageal cancer survival could be attributed to sex- specific risk exposures, such as age at diagnosis, race, socioeconomic status, smoking, drinking, and histological type. The aim of our study is to investigate the role of sex disparities in survival of patients who underwent surgery for esophageal cancer. A systematic review and meta-analysis of the existing literature in PubMed, EMBASE, and CENTRAL from December 1966 to February 2023, was held. Studies that reported sex-related differences in survival outcomes of patients who underwent esophagectomy for esophageal cancer were identified. A total of 314 studies were included in the quantitative analysis. Statistically significant results derived from 1-year and 2-year overall survival pooled analysis with Relative Risk (RR) 0.93 (95% Confidence Interval (CI): 0.90-0.97, I2 = 52.00) and 0.90 (95% CI: 0.85-0.95, I2 = 0.00), respectively (RR < 1 = favorable for men). In the postoperative complications analysis, statistically significant results concerned anastomotic leak and heart complications, RR: 1.08 (95% CI: 1.01-1.16) and 0.62 (95% CI: 0.52-0.75), respectively. Subgroup analysis was performed among studies with <200 and > 200 patients, histology types, study continent and publication year. Overall, sex tends to be an independent prognostic factor for esophageal carcinoma. However, unanimous results seem rather obscure when multivariable analysis and subgroup analysis occurred. More prospective studies and gender-specific protocols should be conducted to better understand the modifying role of sex in esophageal cancer prognosis.

Development of a TLR-Based Model That Can Predict Prognosis, Tumor Microenvironment, and Drug Response for Esophageal Squamous Cell Carcinoma

The toll-like receptor (TLR) family is an important class of proteins involved in the immune response. However, little is known about the association between TLRs and Esophageal squamous cell cancer (ESCC). We explored differentially expressed genes (DEGs) between ESCC and esophagus tissues in TCGA and GTEx database. By taking the intersection with TLR gene set and using univariate Cox analysis and multivariate Cox regression analysis to discriminate the hub genes, we created a TLR-prognostic model. Our model separated patients with ESCC into high- and low-risk score (RS) groups. Prognostic analysis was performed with Kaplan-Meier curves. The two groups were also compared regarding tumor immune microenvironment and drug sensitivity. Six hub genes (including CD36, LGR4, MAP2K3, NINJ1, PIK3R1, and TRAF3) were screened to construct a TLR-prognostic model. High-RS group had a worse survival (p < 0.01), lower immune checkpoint expression (p < 0.05), immune cell abundance (p < 0.05) and decreased sensitivity to Epirubicin (p < 0.001), 5-fluorouracil (p < 0.0001), Sorafenib (p < 0.01) and Oxaliplatin (p < 0.05). We constructed a TLR-based model, which could be used to assess the prognosis of patients with ESCC, provide new insights into drug treatment for ESCC patients and investigate the TME and drug response.

Lipopolysaccharide induces CCL2 through TLR4 signaling and promotes esophageal squamous cell carcinoma cell proliferation

Poor oral health is an independent risk factor for upper-aerodigestive tract cancers, including esophageal squamous cell carcinoma (ESCC). Our previous findings suggest that high expression of toll-like receptor (TLR) 4, which recognizes lipopolysaccharide (LPS) released from periodontal pathogens, correlates with a poor prognosis after esophagectomy for ESCC. We therefore hypothesized that LPS influences cancer cell proliferation and disease progression in ESCC. We used 8 ESCC cell lines to investigate how LPS affects ESCC cell proliferation and migration activity. We also assessed mRNA and protein expression to determine how LPS affects cytokine production and whether blocking TLR4 signaling attenuates that effect. We also used a mouse xenograft model to investigate whether LPS upregulates ESCC tumor progression in vivo. We then determined whether C-C motif chemokine ligand 2 (CCL2) expression in clinical samples correlates with 5-year overall survival (OS) and disease-specific survival (DSS) in ESCC patients after esophagectomy. LPS significantly upregulated cell proliferation and migration in all ESCC lines. It also upregulated CCL2 production. In vivo, subcutaneous LPS administration significantly increased ESCC tumor volume in mice. In clinical samples, high CCL2 expression significantly correlated with 5-year OS and DSS. There was also a significant correlation between CCL2 and TLR4 expression status, suggesting the involvement of an LPS-TLR4-CCL2 cascade in clinical settings. LPS significantly upregulates cell proliferation and tumor progression through an LPS-TLR4-CCL2 cascade and influences prognosis after esophagectomy for ESCC. This suggests improving the oral environment has the potential to improve the prognosis of ESCC patients after esophagectomy.

Bacteroidetes promotes esophageal squamous carcinoma invasion and metastasis through LPS-mediated TLR4/Myd88/NF-κB pathway and inflammatory changes

Gut microbiota plays a crucial role in gastrointestinal tumors. Additionally, gut microbes influence the progression of esophageal cancer. However, the major bacterial genera that affect the invasion and metastasis of esophageal cancer remain unknown, and the underlying mechanisms remain unclear. Here, we investigated the gut flora and metabolites of patients with esophageal squamous cell carcinoma and found abundant Bacteroides and increased secretion and entry of the surface antigen lipopolysaccharide (LPS) into the blood, causing inflammatory changes in the body. We confirmed these results in a mouse model of 4NQO-induced esophageal carcinoma in situ and further identified epithelial-mesenchymal transition (EMT) occurrence and TLR4/Myd88/NF-κB pathway activation in mouse esophageal tumors. Additionally, in vitro experiments revealed that LPS from Bacteroides fragile promoted esophageal cancer cell proliferation, migration, and invasion, and induced EMT by activating the TLR4/Myd88/NF-κB pathway. These results reveal that Bacteroides are closely associated with esophageal cancer progression through a higher inflammatory response level and signaling pathway activation that are both common to inflammation and tumors induced by LPS, providing a new biological target for esophageal cancer prevention or treatment.

Fusobacterium nucleatum: An Overview of Evidence, Demi-Decadal Trends, and Its Role in Adverse Pregnancy Outcomes and Various Gynecological Diseases, including Cancers

Gynecological and obstetric infectious diseases are crucial to women's health. There is growing evidence that links the presence of Fusobacterium nucleatum (F. nucleatum), an anaerobic oral commensal and potential periodontal pathogen, to the development and progression of various human diseases, including cancers. While the role of this opportunistic oral pathogen has been extensively studied in colorectal cancer in recent years, research on its epidemiological evidence and mechanistic link to gynecological diseases (GDs) is still ongoing. Thus, the present review, which is the first of its kind, aims to undertake a comprehensive and critical reappraisal of F. nucleatum, including the genetics and mechanistic role in promoting adverse pregnancy outcomes (APOs) and various GDs, including cancers. Additionally, this review discusses new conceptual advances that link the immunomodulatory role of F. nucleatum to the development and progression of breast, ovarian, endometrial, and cervical carcinomas through the activation of various direct and indirect signaling pathways. However, further studies are needed to explore and elucidate the highly dynamic process of host-F. nucleatum interactions and discover new pathways, which will pave the way for the development of better preventive and therapeutic strategies against this pathobiont.

Pretreatment periodontitis is predictive of a poorer prognosis after esophagectomy for esophageal cancer

BACKGROUND

Poor oral health is an independent risk factor for upper-aerodigestive tract cancers, including esophageal cancer. Several studies have investigated short-term outcomes after esophagectomy and the impact of periodontal disease, but few have examined the impact of periodontal disease on long-term outcomes. The purpose of this study was to investigate the rate of periodontitis among esophagectomy patients and the prognostic value of periodontitis and its effect on prognosis after esophagectomy.

METHODS

A total of 508 patients who underwent esophagectomy received oral health care from a dentist before cancer treatment at Akita University Hospital between January 2009 and December 2021. We assessed the presence and severity of the patients' periodontitis and divided them into no-periodontitis, mild periodontitis, severe periodontitis and edentulous jaw groups. We then assessed 10-year overall survival (OS) and disease-specific survival (DSS) and determined whether periodontitis was an independent prognostic factor affecting OS and DSS.

RESULTS

We found that 101 (19.9%) patients had no periodontitis, 207 (40.8%) had mild periodontitis, 176 (34.6%) had severe periodontitis requiring tooth extraction, and 24 (4.7%) had edentulous jaw. Both OS and DSS were significantly poorer in the periodontitis than no-periodontitis group (p < 0.001). In detail, the edentulous jaw group had the poorest prognosis (p < 0.001). Multivariate analysis showed that periodontitis was an independent risk factor affecting OS and DSS.

CONCLUSION

Esophageal cancer patients had a high prevalence of periodontitis. Moreover, the presence of periodontitis and severity of periodontitis are independent risk factors contributing to a poorer prognosis after esophagectomy.

Preoperative inspiratory muscle weakness as a risk factor of postoperative pulmonary complications in patients with esophageal cancer

OBJECTIVE

We examined whether preoperative inspiratory muscle weakness (IMW) is a risk factor for postoperative pulmonary complications (PPCs) in patients with esophageal cancer who underwent subtotal esophagectomy.

METHODS

This single-center retrospective cohort study enrolled patients with esophageal cancer who underwent a scheduled subtotal esophagectomy between June 2020 and May 2022. Maximal inspiratory pressure (MIP) was measured as inspiratory muscle strength using a respiratory dynamometer, and we defined IMW as MIP < 80% of the predicted value. Our primary outcome comprised overall PPCs. We investigated the relationship between IMW and PPCs using the Bayesian logistic regression model.

RESULTS

After exclusion, 72 patients were included in this study. IMW was identified in 26 patients (36%), and PPCs developed in 28 patients (39%). Among patients with IMW, 15 (58%) developed PPCs. Preoperative IMW was associated with PPCs (mean odds ratio [OR]: 3.58; 95% credible interval [95% CrI]: 1.29, 9.73) in the unweighted model. A similar association was observed in the weighted model adjusted for preoperative and intraoperative contributing factors (mean OR: 4.15; 95% CrI: 2.04, 8.45).

CONCLUSIONS

Preoperative IMW was associated with PPCs in patients with esophageal cancer who underwent subtotal esophagectomy. This association remained after adjusting for preoperative and intraoperative contributing factors.

High TLR6 Expression Status Predicts a More Favorable Prognosis after Esophagectomy for Locally Advanced Thoracic Esophageal Squamous Cell Carcinoma

Most so-called "beneficial bacteria" in gut microbiota are Gram-positive, and TLR6 recognizes the peptidoglycan (PGN) present in their cell walls. We hypothesized that a high TLR6 expression status predicts a more favorable prognosis after esophagectomy. We used an ESCC tissue microarray (TMA) to examine TLR6 expression status in ESCC patients and to determine whether TLR6 expression status correlates with prognosis after curative esophagectomy. We also examined whether PGN influences the cell proliferation activity of ESCC lines. Clinical ESCC samples from 177 patients tested for the expression of TLR6 were categorized as 3+ (n = 17), 2+ (n = 48), 1+ (n = 68), or 0 (n = 44). High TLR6 expression (3+ and 2+) correlated with significantly more favorable 5-year overall survival (OS) and disease-specific survival (DSS) after esophagectomy than a lower TLR6 expression (1+ and 0). Univariate and multivariate analyses showed that TLR6 expression status is an independent prognostic factor that affects 5-year OS. PGN significantly inhibited the cell proliferation activity of ESCC lines. This is the first study to show that high TLR6 expression status predicts a more favorable prognosis in locally advanced thoracic ESCC patients after curative esophagectomy. PGN released from "beneficial bacteria" seems to have potential to inhibit the cell proliferation activity of ESCC.

Preoperative evaluation of oral hygiene may predict the overall survival of patients with esophageal cancer

BACKGROUND

Previously, the association between tooth loss and prognosis after esophagectomy was reported; however, the presence of periodontal disease has not been assessed. This study investigated the association between the degree of oral hygiene, as evaluated by tooth loss and periodontal disease, and the prognosis of patients with esophageal cancer.

METHODS

A total of 163 esophageal cancer patients who underwent surgery with perioperative oral care and examination were enrolled. We assessed the periodontal pocket depth for the presence of periodontal disease and established a periodontal pocket index, defined as the sum of the periodontal pocket depth of the remaining tooth divided by the total count of the remaining teeth. Patients were divided into three groups: Group A (tooth loss < 13 and periodontal pocket index < 3.67); Group B (tooth loss < 13 and periodontal pocket index ≥ 3.67); and Group C (tooth loss ≥ 13). Overall survival and cancer-specific survival were analyzed, and a multivariate analysis was performed.

RESULTS

There was a significant difference in the 5-year overall survival rates between the groups (A:B:C = 74.8%:62.8%:50.5%; p = 0.0098), but not in the 5-year cancer-specific survival rates (A:B:C = 80.2%:64.2%:62.2%; p = 0.0849). In multivariate analysis, oral hygiene (tooth loss < 13 and periodontal pocket index ≥ 3.67 + tooth loss ≥ 13; p = 0.041) was a significant independent poor prognostic factor for overall survival.

CONCLUSIONS

Oral evaluation, focusing on tooth loss and periodontal disease, is meaningful in predicting the long-term prognosis of postoperative esophageal cancer patients.

Oral Microbiota Variation: A Risk Factor for Development and Poor Prognosis of Esophageal Cancer

Recent studies have shown that oral microbiota play an important role in the esophageal cancer (EC) initiation and progression, suggesting that oral microbiota is a new risk factor for EC. The composition of the microbes inhabiting the oral cavity could be perturbed with continuous factors such as smoking, alcohol consumption, and inflammation. The microbial alteration involves the decrease of beneficial species and the increase of pathogenic species. Experimental evidences suggest a significant role of oral commensal organisms in protecting hosts against EC. By contrast, oral pathogens, especially Porphyromonas gingivalis and Fusobacterium nucleatum, give rise to the risk for developing EC through their pro-inflammatory and pro-tumorigenic activities. The presences of oral dysbiosis, microbial biofilm, and periodontitis in EC patients are found to be associated with invasive cancer phenotypes and poor prognosis. The mechanism of oral bacteria in EC progression is complex, which involves a combination of cytokines, chemokines, oncogenic signaling pathways, cell surface receptors, the degradation of extracellular matrix, and cell apoptosis. From a clinical perspective, good oral hygiene, professional oral care, and rational use of antibiotics bring positive impacts on oral microbial balance, thus helping individuals reduce the risk of EC, inhibiting postoperative complications among EC patients, and improving the efficiency of chemoradiotherapy. However, current oral hygiene practices mainly focus on the oral bacteria-based predictive and preventive purposes. It is still far from implementing microbiota-dependent regulation as a therapy for EC. Further explorations are needed to render oral microbiota a potential target for treating EC.

Bacterial Translocation in Gastrointestinal Cancers and Cancer Treatment

In recent years, there has been increasing evidence that gut microbiota is associated with the onset and exacerbation of various diseases, such as gastrointestinal cancer. For instance, it is well known that local inflammation of the intestinal tract in colorectal cancer that is caused by the increased number of Fusobacterium, due to changes in the intestinal bacterial flora, is involved in carcinogenesis. In contrast, gut bacteria or their products, pathogen-associated molecular patterns, not only cause intestinal inflammation but also invade the bloodstream through dysbiosis and gut barrier dysfunction, thereby leading to systemic inflammation, namely bacterial translocation. The involvement of bacterial translocation in the carcinogenesis of gastrointestinal cancers and their prognosis is increasingly being recognized. The Toll-like receptor signaling pathways plays an important role in the carcinogenesis of such cancers. In addition, bacterial translocation influences the treatment of cancers such as surgery and chemotherapy. In this review, we outline the concept of bacterial translocation, summarize the current knowledge on the relationship between gut bacteria and gastrointestinal cancer, and provide future perspectives of this field.

6-Shogaol Suppresses the Progression of Liver Cancer via the Inactivation of Wnt/[Formula: see text]-Catenin Signaling by Regulating TLR4

Liver cancer is a gastrointestinal malignant tumor with high lethality. The prognosis of liver cancer remains poor. Compounds derived from natural products have been confirmed to alleviate the progression of various diseases, including cancers. Additionally, 6-Shogaol has been reported to induce apoptosis in liver cancer cells. However, the mechanism by which 6-shogaol regulates apoptosis in liver cancer cells remains unclear. To investigate the function of 6-shogaol in liver cancer, RT-qPCR and western blotting were used to detect the expression of TLR4 and FOXO3a in liver cancer cells, respectively. The OD value of liver cancer cells was measured using the MTT assay. Flow cytometry was used to measure cell apoptosis. 6-Shogaol inhibited the growth of liver cancer cells. TLR4 and Wnt/[Formula: see text]-catenin were upregulated in liver cancer cells, and FOXO3a was inactivated, but 6-Shogaol reversed the expression of TLR4, Wnt/[Formula: see text]-catenin and FOXO3a in liver cancer cells. Additionally, TLR4 overexpression partially reversed the inhibitory effect of 6-shogaol on the progression of liver cancer cells via Wnt/[Formula: see text]-catenin signaling. Furthermore, the 6-shogaol-induced increase in FOXO3a expression in liver cancer was notably suppressed by TLR4 or Wnt/[Formula: see text]-catenin upregulation. Thus, 6-Shogaol suppresses the progression of liver cancer by mediating Wnt/[Formula: see text]-catenin signaling and is a potential agent for the treatment of liver cancer.

Prognostic impact of LY6K and CDCA1 expression for patients with esophageal squamous cell carcinoma

AIM

In the present study, we investigated the relationship between the expressions of two cancer testis antigens (CTA), LY6K (lymphocyte antigen 6 complex locus K) and CDCA1 (cell division cycle associated 1), in esophageal squamous cell carcinoma (ESCC) tumors and the long-term outcomes of patients with ESCC to clarify the clinical significance of LY6K and CDCA1 expression in ESCC tumors.

METHODS

A total of 175 patients with thoracic ESCC who had undergone a thoracic esophagectomy with three-field lymphadenectomy without neoadjuvant therapy were retrospectively reviewed in this study. LY6K and CDCA1 expressions were evaluated in tumor tissues using immunohistochemical (IH) staining.

RESULTS

Median patient age was 63 years; 159 patients (90.9%) were men. Ninety-four patients (55.3%) were LY6K-positive, and 85 patients (48.6%) were CDCA1-positive. The LY6K-positive group had a significantly worse overall survival (OS) than the LY6K-negative group (P = 0.012), and the CDCA1-positive group had a significantly worse OS than the CDCA1-negative group (P = 0.010). A multivariate analysis suggested that pathological N stage, venous invasion, LK6Y-positive and CDCA1-positive were independent prognostic factors. The patients were classified into four groups according to the staining pattern combinations of the two CTA. The LY6K-positive and CDCA1-positive group was found to have a significantly poorer outcome than the other groups.

CONCLUSION

ESCC patients with a combination of LY6K and CDCA1 expression in their tumor tissues had a worse prognosis than all the other ESCC patients and it was an independent factor associated with prognosis for patients with ESCC.

Neoadjuvant Chemoradiotherapy Followed by Esophagectomy with Three-Field Lymph Node Dissection for Thoracic Esophageal Squamous Cell Carcinoma Patients with Clinical Stage III and with Supraclavicular Lymph Node Metastasis

Simple Summary

This study aimed to clarify the efficacy of neoadjuvant chemoradiotherapy (NACRT) followed by esophagectomy with three-field lymph node (LN) dissection for clinical Stage III patients and for clinical Stage IVB patients with supraclavicular LN metastasis as the only distant metastatic factor. We observed that NACRT followed by esophagectomy with three-field lymph node dissection is feasible and offers the potential for long-term survival of these patients. It is also suggested that supraclavicular LNs should be treated as regional LNs at least in patients with upper and middle thoracic esophageal squamous cell carcinoma (ESCC).

Abstract

Background: Neoadjuvant chemoradiotherapy (NACRT) followed by esophagectomy is now the standard treatment for patients with resectable advanced thoracic esophageal squamous cell carcinoma (ESCC) worldwide. However, the efficacy of NACRT followed by esophagectomy with three-field lymph node dissection for clinical Stage III patients and for clinical Stage IVB patients with supraclavicular LN metastasis has not yet been determined. Methods: Between 2008 and 2018, 94 ESCC patients diagnosed as clinical Stage III and 18 patients diagnosed as clinical Stage IVB with supraclavicular LN metastasis as the only distant metastatic factor were treated with NACRT followed by esophagectomy with extended lymph node dissection at Akita University Hospital. Long-term survival and the patterns of recurrence in these 112 patients were analyzed. Results: The median follow-up period of censored cases was 60 months. The five-year OS and DSS rates among the clinical Stage III patients were 57.6% and 66.6%, respectively. The five-year OS and DSS rates among the clinical Stage IVB patients were 41.3% and 51.6%, respectively. The most frequent recurrence pattern was distant metastasis (69.2%) in the Stage III patients and LN metastasis (75.0%) in the Stage IVB patients. Conclusion: NACRT followed by esophagectomy with three-field LN dissection is feasible and offers the potential for long-term survival of clinical Stage III ESCC patients and even clinical Stage IVB patients with supraclavicular LN metastasis as the only distant metastatic factor. At least in patients with upper and middle thoracic ESCC, treating supraclavicular LNs as regional LNs seems to be appropriate.

TLR4 promoter rs1927914 variant contributes to the susceptibility of esophageal squamous cell carcinoma in the Chinese population

Background

Toll-like receptor 4 (TLR4), as a key regulator of both innate and acquired immunity, has been linked with the development of various cancers, including esophageal cancer. This study aims to analyze the association of potential functional genetic polymorphisms in TLR4 with the risk of esophageal cancer.

Methods

This case-control study involved in 480 ESCC patients and 480 health controls. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to genotype TLR4 rs1927914 polymorphism. Taqman probe method was used to determine the genotypes of TLR4 rs11536891 and rs7873784 variants. The relationship between TLR4 genetic variation and ESCC risk was analyzed by Logistic regression model by calculating the odds ratio (OR) and 95% confidence interval (95% CI).

Results

Compared with TLR4 rs1927914 AA genotype carriers, GG carriers had a lower ESCC risk (OR = 0.59, 95% CI [0.38–0.93], P = 0.023). Stratification analysis by age showed that TLR4 rs1927914 GG could affect the risk of ESCC in elderly people (OR = 0.59, 95% CI [0.36–0.97]). Smoking stratification analysis indicated that rs1927914 GG carriers were related to ESCC susceptibility among non-smokers (OR = 0.36, 95% CI [0.18–0.73]). Dual luciferase reporter assay suggested that rs1927914 G-containing TLR4 promoter displayed a 1.76-fold higher luciferase activity than rs1927914 A-containing counterpart in KYSE30 cells. Electrophoretic mobility shift assay (EMSA) showed the KYSE30 cell nuclear extract was able to bind the probe with rs1927914 G allele and this DNA-protein interaction could be eliminated by competition assays with unlabeled rs1927914 G probe, which indicating that the binding is sequence-specific. Our results also showed that TLR4 rs7873784 (G>C) and rs11536891 (T>C) conformed to complete genetic linkage. The genotype distributions of TLR4 rs11536891 variant among ESCC patients and normal controls have no statistical significance.

Conclusion

The TLR4 rs1927914 variant contributes to the ESCC risk by effecting the promoter activity.

Chromobox 2 Expression Predicts Prognosis After Curative Resection of Oesophageal Squamous Cell Carcinoma

BACKGROUND/AIM

To investigate the function of chromobox 2 (CBX2) in oesophageal squamous cell carcinoma (OSCC).

MATERIALS AND METHODS

We used real-time quantitative reverse transcription PCR (qRT-PCR) and immunohistochemistry to determine CBX2 expression levels in 13 human OSCC cell lines and clinical specimens of two independent cohorts of patients with OSCC.

RESULTS

PCR array analysis revealed that CBX2 was co-ordinately expressed with WNT5B in OSCC cell lines. RT-qPCR analysis of clinical samples revealed a high tumour-specific CBX2 expression compared with normal oesophageal tissues. High CBX2 expression was significantly associated with shorter disease-specific survival, hematogenous recurrence, and overall recurrence. Analysis of tissue microarrays of one cohort revealed that patients with higher CBX2 levels tended to have a shorter disease-specific survival.

CONCLUSION

CBX2 overexpression in OSCC tissues may serve as a novel biomarker for predicting survival and hematogenous recurrence.

Potential mechanisms of tumor progression associated with postoperative infectious complications

There is increasing evidence that postoperative infectious complications (PICs) are associated with poor prognosis after potentially curative surgery. However, the role that PICs play in tumor development remains unclear. In this article, we reviewed the literature for novel insights on the mechanisms of cancer progression associated with PICs. The Medline and EMBASE databases were searched for publications regarding the role of suppression of antitumor immunity by PIC in tumor progression and selected 916 manuscripts were selected for this review. In addition, a summary of the authors' own experimental data from this field was set in the context of current knowledge regarding cancer progression under septic conditions. Initially, sepsis/microbial infection dramatically activates the systemic immune system with increases in pro-inflammatory mediators, which results in the development of systemic inflammatory response syndrome; however, when sepsis persists in septic patients, a shift toward an anti-inflammatory immunosuppressive state, characterized by macrophage deactivation, reduced antigen presentation, T cell anergy, and a shift in the T helper cell pattern to a predominantly TH2-type response, occurs. Thus, various cytokine reactions and the immune status dynamically change during microbial infection, including PIC. We proposed three possible mechanisms for the tumor progression associated with PIC: first, a mechanism in which microbes and/or microbial PAMPs may be directly involved in cancer growth; second, a mechanism in which factors released from immunocompetent cells during infections may affect tumor progression; and third, a mechanism in which factors suppress host tumor immunity during infections, which may result in tumor progression. A more detailed understanding by surgeons of the immunological features in cancer patients with PIC can subsequently open new avenues for improving unfavorable long-term oncological outcomes associated with PICs.

Comparison of the incidences of anastomotic leakage when PDSII or LACLON are used in esophago-gastric conduit handsewn anastomosis after esophagectomy

The incidence of anastomotic leakage after esophagectomy remains around 10%. It was previously reported that PDSII rapidly loses tensile strength at pH 1.0 and pH 8.5. By contrast, LACLON degradation is reportedly insensitive to pH. We therefore compared LACLON with PDSII for esophago-gastric conduit, layer-to-layer, handsewn anastomosis. Between January 2016 and January 2020, 90 patients who received posterior mediastinal gastric conduit reconstruction with layer-to-layer handsewn anastomosis (51 using PDSII and 39 using LACLON) at Akita University Hospital were enrolled. The incidence of anastomotic leakage was significantly lower in the LACLON (2.6%, 1/39 patients) than PDSII group (15.7%, 8/51 patients) (p = 0.0268). Multivariable logistic analysis showed the risk of anastomotic leakage was significantly greater with PDSII than LACLON (odds ratio 11.01; 95% CI 1.326–277.64; p = 0.024). The percentages of time the pH was higher than 8 on the gastric conduit side of the anastomosis were 3.1%, 5.7%, 20.9% and 80.5%, respectively, in the four most recent patients. The present study showed that pH at the anastomosis soon after esophagectomy tends to be alkaline rather than acidic, which raises the possibility that this alkalinity facilitates the deterioration of surgical sutures including PDSII.