Peri-operative therapy for operable gastroesophageal adenocarcinoma: past, present and future

Perioperative outcomes in patients who undergo neoadjuvant chemoradiotherapy versus chemotherapy versus up-front surgery in patients with oesophageal cancer

BACKGROUND

Oesophagectomy is the mainstay of curative treatment for oesophageal cancer. The role of neoadjuvant therapy has evolved over time as evidence for its survival benefit comes to hand. Clinician reluctance to offer patients neoadjuvant therapy may be based on the perception that patients receiving treatment before surgery may be exposed to a greater risk of perioperative complications. The aim of this study was to examine short-term outcomes in patients who undergo neoadjuvant therapy versus up-front surgery in patients with oesophageal cancer.

METHODS

This was a retrospective cohort study of prospectively collated data from 2001 to 2020 of patients undergoing resection for oesophageal cancer. Patients who had neoadjuvant chemoradiotherapy, chemotherapy and up-front surgery were compared for perioperative morbidity (via the Clavien-Dindo classification), length of stay, unplanned readmission, and 30- and 90-day mortality. Logistic regression was performed to predict perioperative morbidity following surgery.

RESULTS

In total, 284 patients underwent an oesophagectomy. Most patients received neoadjuvant treatment (41% received chemoradiotherapy (117/284), 33% received chemotherapy (93/284)), and 26% of patients received up-front surgery (74/284). Patients who received neoadjuvant chemoradiotherapy or up-front surgery were more likely to have a complication (57%, 67/117 and 57%, 43/74) than patients who received neoadjuvant chemotherapy only (38%, 35/93, P = 0.009). The 30- and 90-day mortality rates were 1.4% (n = 4) and 2.8% (n = 8), respectively, with no difference between the use of neoadjuvant therapy.

CONCLUSION

In this series, we found that patients who received neoadjuvant treatment could undergo oesophagectomy with curative intent with acceptable postoperative morbidity and mortality.

Efficacy and safety of neoadjuvant sintilimab in combination with FLOT chemotherapy in patients with HER2-negative locally advanced gastric or gastroesophageal junction adenocarcinoma: an investigator-initiated, single-arm, open-label, phase II study

BACKGROUND

The addition of immune checkpoint inhibitors to neoadjuvant chemotherapy in operable advanced gastric or gastroesophageal junction (G/GEJ) cancer aroused wide interest. This study was designed to assess the efficacy and safety of neoadjuvant sintilimab, a programmed cell death protein-1 (PD-1) inhibitor, in combination with fluorouracil, leucovorin, oxaliplatin, and docetaxel (FLOT) chemotherapy for HER2-negative locally advanced G/GEJ cancer.

METHODS

Eligible patients with clinical stage cT4 and/or cN+M0 G/GEJ cancer were enroled in this phase II study. Patients received neoadjuvant sintilimab (200 mg every 3 weeks) for three cycles plus FLOT (50 mg/m 2 docetaxel, 80 mg/m 2 oxaliplatin, 200 mg/m 2 calcium levofolinate, 2600 mg/m 2 5-fluorouracil every 2 weeks) for four cycles before surgery, followed by four cycles of adjuvant FLOT with same dosages after resection. The primary endpoint was the pathological complete response (pCR) rate.

RESULTS

Thirty-two patients were enroled between August 2019 and September 2021, with a median follow-up of 34.8 (95% CI, 32.8-42.9) months. Thirty-two (100%) patients received neoadjuvant therapy, and 29 underwent surgery with an R0 resection rate of 93.1%. The pCR (TRG0) was achieved in 5 (17.2%; 95% CI, 5.8-35.8%) patients, and the major pathological response was 55.2%. Twenty-three (79.3%) patients had T downstaging, 21 (72.4%) had N downstaging, and 19 (65.5%) had overall TNM downstaging. Six (20.7%) patients experienced recurrence. Patients achieving pCR showed better event-free survival (EFS), disease-free survival (DFS), and overall survival (OS) than non-pCR. The estimated 3-year EFS rate, 3-year DFS rate, and 3-year OS rate were 71.4% (95% CI, 57.2-89.2%), 78.8% (95% CI, 65.1-95.5%), and 70.9% (95% CI, 54.8-91.6%), respectively. The objective response rate and disease control rate were 84.4% (95% CI, 68.3-93.1%) and 96.9% (95% CI, 84.3-99.5%), respectively. Twenty-five (86.2%) received adjuvant therapy. The main grade ≥3 treatment-related adverse events (TRAEs) were lymphopenia (34.4%), neutropenia (28.1%), and leukopenia (15.6%). no patients died from TRAE. The LDH level exhibited a better predictive value to pathological responses than PD-L1 and MSI status.

CONCLUSIONS

The study demonstrated an encouraging efficacy and manageable safety profile of neoadjuvant sintilimab plus FLOT in HER2-negative locally advanced G/GEJ cancer, which suggested a potential therapeutic option for this population.

Clinical significance of CD166 and HER-2 in different types of gastric cancer

INTRODUCTION

Cluster of differentiation 166 (CD166), a cancer stem cell (CSC) marker, and human epidermal growth factor receptor 2 (HER-2) are expressed in a diversity of malignancies and is associated with tumor progression. Although studies regarding the importance of CSC markers and HER-2 in gastric cancer (GC) have rapidly developed, their clinicopathological, prognosis, and diagnosis value still remain unsatisfying in GC. Therefore, the present study aims to investigate the clinical, prognostic, and diagnostic significance of CD166 and HER-2 in different histological types of GC.

MATERIALS AND METHODS

Bioinformatic analysis was applied to determine the clinical importance of CD166 and HER-2 expression based on their tissue localization in primary GC tumors and the normal adjacent samples. The expression patterns, clinical significance, prognosis, and diagnosis value of CD166 and HER-2 proteins in tissue microarrays (TMAs) of 206 GC samples, including Signet Ring Cell (SRC) and intestinal types and also 28 adjacent normal tissues were evaluated using immunohistochemistry (IHC).

RESULTS

The results indicated that the expression of CD166 (membranous and cytoplasmic) and HER-2 were significantly up-regulated in tumor cells compared to adjacent normal tissues (P = 0.010, P < 0.001, and P = 0.011, respectively). A statistically significant association was detected between a high level of membranous expression of CD166 and lymphovascular invasion (P = 0.006); We also observed a statistically significant association between high cytoplasmic expression of CD166 protein and more invasion of the subserosa (P = 0.040) in the SRC type. In contrast, there was no correlation between the expression of HER-2 and clinicopathologic characteristics. Both CD166 and HER-2 showed reasonable accuracy and high specificity as diagnostic markers.

CONCLUSION

Our results confirmed that increased membranous and cytoplasmic expression of CD166 showed clinical significance in the SRC type and is associated with the progression of the disease and more aggressive tumor behaviors. These findings can be used to assist in designating subgroups of patients that require different follow-up strategies, and also, they might be utilized as the prognostic or diagnostic biomarkers in these types of GC for prospective clinical application.

Gastric cancer mesenchymal stem cells promote tumor glycolysis and chemoresistance by regulating B7H3 in gastric cancer cells

Despite surgical treatment combined with multidrug therapy having made some progress, chemotherapy resistance is the main cause of recurrence and death of gastric cancer (GC). Gastric cancer mesenchymal stem cells (GCMSCs) have been reported to be correlated with the limited efficacy of chemotherapy in GC, but the mechanism of GCMSCs regulating GC resistance needs to be further studied. The gene set enrichment analysis (GSEA) was performed to explore the glycolysis-related pathways heterogeneity across different cell subpopulations. Glucose uptake and lactate production assays were used to evaluate the importance of B7H3 expression in GCMSCs-treated GC cells. The therapeutic efficacy of oxaliplatin (OXA) and paclitaxel (PTX) was determined using CCK-8 and colony formation assays. Signaling pathways altered by GCMSCs-CM were revealed by immunoblotting. The expression of TNF-α in GCMSCs and bone marrow mesenchymal stem cells (BMMSCs) was detected by western blot analysis and qPCR. Our results showed that the OXA and PTX resistance of GC cells were significantly enhanced in the GCMSCs-CM treated GC cells. Acquired OXA and PTX resistance was characterized by increased cell viability for OXA and PTX, the formation of cell colonies, and decreased levels of cell apoptosis, which were accompanied by reduced levels of cleaved caspase-3 and Bax expression, and increased levels of Bcl-2, HK2, MDR1, and B7H3 expression. Blocking TNF-α in GCMSCs-CM, B7H3 knockdown or the use of 2-DG, a key enzyme inhibitor of glycolysis in GC cells suppressed the OXA and PTX resistance of GC cells that had been treated with GCMSCs-CM. This study shows that GCMSCs-CM derived TNF-α could upregulate the expression of B7H3 of GC cells to promote tumor chemoresistance. Our results provide a new basis for the treatment of GC.

Upregulation of LINC00501 by H3K27 acetylation facilitates gastric cancer metastasis through activating epithelial-mesenchymal transition and angiogenesis

BACKGROUND

The molecular mechanism of the significant role of long noncoding RNAs (lncRNAs) in the progression and metastasis of gastric cancer (GC) remains largely elusive. Our objective is to detect overexpressed lncRNA in GC and investigate its role in promoting epithelial-mesenchymal transition and tumour microenvironment remodel.

METHODS

LncRNA differential expression profile in GC was analysed using RNA microarrays. The level of LINC00501 was evaluated in both GC patient tissues and GC cell lines by quantitative reverse transcription PCR and large-scale (n = 304) tissue microarray. To explore the biological role and regulatory driver of LINC00501 in GC, various experimental techniques including Chromatin isolation by RNA purification (ChIRP), RNA immunoprecipitation (RIP), chromatin immunoprecipitation (ChIP) assay, dual luciferase assays were performed.

RESULTS

Clinically, it was observed that LINC00501 level was abnormal overexpression in GC tissue and was associated with GC progression and distant metastasis. Gain and loss molecular biological experiments suggested that LINC00501, promoted EMT process and angiogenesis of GC. Mechanically, the enrichment of H3K27 acetylation in LINC00501 promoter region contributed to the increase of LINC00501 in GC. LINC00501 transactivated transcription of SLUG, by recruiting hnRNPR to its promoter. The growth of GC was inhibited both in vitro and in vivo by suppressing the level of LINC00501 using pharmacological intervention from the histone acetyltransferase (HAT) inhibitor -C646.

CONCLUSIONS

This study suggests that LINC00501 promotes GC progression via hnRNPR/SLUG pathway, which indicates a promising biomarker and target for GC.

Effect of Microsatellite Status and Pan-Immune-Inflammation Score on Pathological Response in Patients with Clinical Stage III Stomach Cancer Treated with Perioperative Chemotherapy

Background and Objective: This study evaluated the relationship between microsatellite status (MSI) and pan-immune-inflammation score (PIV) in tumor response to neoadjuvant chemotherapy (NAC) in patients with clinical stage III gastric cancer (cStage III GC). Materials and Methods: Microsatellite instability (MSI) status was evaluated based on pathology preparations. Pan-immune-inflammation score (PIV) was obtained from pre-treatment blood tests. The relationship of both parameters with pathological complete response (pCR) was evaluated. Results: A total of 104 patients were included in this study. All the patients were stage III GC patients receiving perioperative treatment. There were 13 patients in total who achieved a pCR response. While CNS was detected in 11 of the patients who achieved a pCR, the MSI status of the other two patients was unknown. No pCR was observed in any patient with MSI-H. According to the cut-off value for PIV, 25 (24%) patients were in the PIV-low (≤53.9) group, while 79 (76%) were in the PIV-high (>53.9) group. Based on univariate analysis, a higher PIV was associated with worse outcomes for pathological response, disease recurrence, and survival (p < 0.05). Conclusions: In patients with clinically stage III GC, the presence of MSI-H may predict no benefit from perioperative treatment. Conversely, a pre-treatment PIV score using specific cut-off values may provide a positive prediction of pathological response and survival.

Expression of CDK6 in Stomach Cancer and the Effect of CDK4/6 Inhibitor PD-0332991 on the Function of Stomach Cancer Cells

Objective

To study the expression and prognostic value of CDK6 in stomach cancer and the function of CDK4/6 inhibitor PD-0332991 on the proliferation of stomach cancer cells.

Methods

Immunohistochemistry was used to detect the expression of CDK6 in stomach cancer tissues and adjacent normal tissues and to analyze the effect of CDK6 on clinicopathological parameters of stomach cancer patients. Kaplan-Meier plotter was employed to study the relationship between CDK6 and overall survival in stomach cancer. Western blot and RT-PCR were used to detect protein and gene expression of CDK6 in different cells. The effects of CDK4/6 inhibitor PD-0332991 on apoptosis and aging of stomach cancer cells were detected by flow cytometry and β-galactosidase aging staining assay. The effects of CDK4/6 inhibitor PD-0332991 on the invasion and migration of stomach cancer cells were explored by the wound healing experiment and the Transwell experiment. The supernatant of stomach cancer cells was collected, and the effect of CDK4/6 inhibitor PD-0332991 on tumor markers of stomach cancer cells was detected by biochemical immunoassay.

Results

(1) CDK6 was highly expressed in stomach cancer tissues and cells. (2) Abnormally elevated CDK6 expression results in shorter survival in stomach cancer patients. (3) CDK4/6 inhibitor PD-0332991 could block the proliferation of stomach cancer cells, but not stomach epithelial proliferation. PD-0332991 could inhibit the secretion of pro-GRP by MGC 823. (4) PD-0332991 could advance the development of the apoptosis and senescence of stomach cancer cells and suppressed the invasion and migration of stomach cancer cells.

Conclusion

CDK6 expression is elevated in gastric cancer, and the CDK4/6 inhibitor PD-0332991 can remarkably promote apoptosis and senescence of stomach cancer cells and effectively inhibit the migration and invasion of stomach cancer cells.

Identification of Tumor Mutation Burden, Microsatellite Instability, and Somatic Copy Number Alteration Derived Nine Gene Signatures to Predict Clinical Outcomes in STAD

Genomic features, including tumor mutation burden (TMB), microsatellite instability (MSI), and somatic copy number alteration (SCNA), had been demonstrated to be involved with the tumor microenvironment (TME) and outcome of gastric cancer (GC). We obtained profiles of TMB, MSI, and SCNA by processing 405 GC data from The Cancer Genome Atlas (TCGA) and then conducted a comprehensive analysis though “iClusterPlus.” A total of two subgroups were generated, with distinguished prognosis, somatic mutation burden, copy number changes, and immune landscape. We revealed that Cluster1 was marked by a better prognosis, accompanied by higher TMB, MSIsensor score, TMEscore, and lower SCNA burden. Based on these clusters, we screened 196 differentially expressed genes (DEGs), which were subsequently projected into univariate Cox survival analysis. We constructed a 9-gene immune risk score (IRS) model using LASSO-penalized logistic regression. Moreover, the prognostic prediction of IRS was verified by receiver operating characteristic (ROC) curve analysis and nomogram plot. Another independent Gene Expression Omnibus (GEO) contained specimens from 109 GC patients was designed as an external validation. Our works suggested that the 9‐gene‐signature prediction model, which was derived from TMB, MSI, and SCNA, was a promising predictive tool for clinical outcomes in GC patients. This novel methodology may help clinicians uncover the underlying mechanisms and guide future treatment strategies.

Preoperative Chemoradiotherapy for Gastroesophageal Junction Adenocarcinoma Modified by PET/CT: Results of Virtual Planning Study

Background and Objectives: The treatment of gastroesophageal junction (GEJ) adenocarcinoma consists of either perioperative chemotherapy or preoperative chemoradiotherapy. Radiotherapy (RT) in the neoadjuvant setting is associated with a higher probability of resections with negative margins (R0) and better tumor regression rate, which might be enhanced by incrementing RT dose with potential impact on treatment results. This virtual planning study demonstrates the feasibility of increasing the dose to GEJ tumor and involved nodes using PET/CT imaging. Materials and Methods: 16 patients from the chemoradiotherapy arm of the phase II GastroPET study were treated by a prescribed dose of 45.0 Gray (Gy) in 25 fractions. PET/CT was performed before treatment. The prescribed dose was virtually boosted on PET/CT-positive areas to 54.0 Gy by 9 Gy in 5 fractions. Dose-volume histograms (DVH) were compared, and normal tissue complication (NTCP) modeling was performed for both dose schedules. Results: DVHs were exceeded in mean heart dose in one case for 45.0 Gy and two cases for 54.0 Gy, peritoneal space volume criterion V_45Gy < 195 ccm in three cases for 54.0 Gy and V_15Gy < 825 ccm in one case for both dose schedules. The left lung volume of 25 Gy isodose exceeded 10% in most cases for both schedules. The NTCP values for the heart, spine, liver, kidneys and intestines were zero for both schemes. An increase in NTCP value was for lungs (median 3.15% vs. 4.05% for 25 × 1.8 Gy and 25 + 5 × 1.8 Gy, respectively, p = 0.013) and peritoneal space (median values for 25 × 1.8 Gy and 25 + 5 × 1.8 Gy were 3.3% and 14.25%, respectively, p < 0.001). Conclusion: Boosting PET/CT-positive areas in RT of GEJ tumors is feasible, but prospective trials are needed.

Induction versus no induction chemotherapy before neoadjuvant chemoradiotherapy and surgery in oesophageal adenocarcinoma: a multicentre randomised phase II trial (NCCTG N0849 [Alliance])

AIM

report primary results from the first multicentre randomised trial evaluating induction chemotherapy prior to trimodality therapy in patients with oesophageal or gastro-oesophageal junction adenocarcinoma. Notably, recent data from a single-institution randomised trial reported that induction chemotherapy prolonged overall survival (OS) in patients with well/moderately differentiated tumours.

METHODS

In this phase 2 trial (28 centres in the U.S. NCI-sponsored North Central Cancer Treatment Group [Alliance]), trimodality-eligible patients (T3-4N0, TanyN+) were randomised to receive induction (docetaxel, oxaliplatin, capecitabine; Arm A) or no induction chemotherapy (Arm B) followed by oxaliplatin/5-fluorouracil/radiation and subsequent surgery. The primary endpoint was the rate of pathologic complete response (pathCR). Secondary/exploratory endpoints were OS and disease-free survival (DFS).

RESULTS

Of 55 patients evaluable for the primary endpoint, the pathCR rate was 28.6% (8/28) in A versus 40.7% (11/27) in B (P = .34). Given interim results indicating futility, accrual was terminated, but patients were followed. After a median follow-up of 60.4 months, a longer median OS in Arm A versus B was unexpectedly observed (3-year rates 57.1% versus 41.7%, respectively) driven by longer DFS after margin-free surgery. In posthoc analysis, induction (versus no induction) chemotherapy was associated with significantly longer OS and DFS among patients with well/moderately differentiated tumours, but not among patients with poorly/undifferentiated tumours (Pinteraction = 0.037).

CONCLUSIONS

Adding induction chemotherapy prior to trimodality therapy did not improve the primary endpoint, pathCR. However, induction chemotherapy was associated with longer median OS, particularly among patients with well/moderately differentiated tumours. These findings may inform further development of curative-intent trials in this disease.

Microsatellite Status Affects Tumor Response and Survival in Patients Undergoing Neoadjuvant Chemotherapy for Clinical Stage III Gastric Cancer

Background

We assessed the association between microsatellite instability-high (MSI-H) and tumor response to neoadjuvant chemotherapy (NAC) as well as its prognostic relevance in patients with clinical stage III gastric cancer (cStage III GC).

Materials and Methods

The NAC + surgery and the control cohorts consisted of 177 and 513 cStage III GC patients, respectively. The clinical and pathological features were compared between patients with MSI-H [n=57 (8.3%)] and microsatellite stability or microsatellite instability-low (MSS/MSI-L) [n=633 (91.7%)]. Radiological and histological response to NAC were evaluated based on response evaluation criteria in solid tumors (RECIST) and tumor regression grade (TRG) systems, respectively. The log-rank test and Cox analysis were used to determine the survival associated with MSI status as well as tumor regression between the two groups in both NAC + surgery and the control cohorts.

Results

A statistically significant association was found between MSI-H and poor histological response to NAC (p=0.038). Significant survival priority of responders over poor-responders could only be observed in MSS/MSI-L but not in MSI-H tumors. However, patients with MSI-H had statistically significantly better survival compared to patients with MSS/MSI-L in both the NAC + surgery (hazard ratio=0.125, 95% CI, 0.017–0.897, p=0.037 ) and the control cohort (hazard ratio=0.479, 95% CI, 0.268–0.856, p=0.013).

Conclusion

MSI-H was associated with poorer regression and better survival after NAC for cStage III GC. TRG evaluation had prognostic significance in MSS/MSI-L but not in MSI-H. Further studies are needed to assess the value of NAC for cStage III GC patients with MSI-H phenotype.

The importance of Epstein-Barr virus infection in the systemic treatment of patients with gastric cancer

The Epstein-Barr virus (EBV) may directly cause the development of EBV-associated gastric cancer (EBVaGC). The prevalence of EBVaGC ranges from 4% to 18%, with a 2-fold higher frequency in males, and in tumors arising in the gastric cardia or corpus and 4 times higher frequency in gastric stump carcinoma. The vast majority of EBVaGC are lymphoepithelioma-like carcinomas. Despite extensive nodal involvement and distant metastases at initial diagnosis, EBVaGC seems to be a distinct etiologic entity with a favorable prognosis. However, the lymphoepithelioma-like carcinomas subtype in EBVaGC cannot be recognized in the current molecular classifications. Neither is there an association between EBV positivity and survival of patients after curative gastrectomy if they received standard adjuvant chemotherapy, nor EBV positivity and prediction of response to neoadjuvant platinum/5-FU-based chemotherapy. Alterations in chemokines and PD-L1 provide theoretical justification for clinical evaluation of immune checkpoint therapy in EBVaGC. Moreover, a higher degree of host immune response was demonstrated in EBVaGC. The current histologic and molecular GC classification does not influence clinical practice. Further research is expected to find convenient methods to assess gastric subtypes in day-to-day practice and to tailor therapy to improve overall survival.