Recent updates in perioperative chemotherapy and recurrence pattern of gastric cancer

Development and validation of a preoperative CT-based risk scoring system for predicting recurrence-free survival in patients undergoing curative surgery for gastric cancer

PURPOSE

The objective of this study was to establish and validate a preoperative risk scoring system that incorporated both clinical and computed tomography(CT) variables to predict recurrence-free survival (RFS) in gastric cancer(GC) patients who underwent curative resection.

METHOD

We retrospectively included consecutive patients with surgically confirmed GC who underwent preoperative CT scans between October 2017 and January 2022. Multivariate Cox regression analysis was employed in the derivation set to identify clinical and CT variables associated with RFS and to construct a risk score. This risk score was subsequently validated in an independent test set.

RESULTS

A total of 346 patients were included in the study, with 213 in the derivation set and 133 in the test set. Five variables, namely ctEMVI, ctBorrmann, visceral obesity, sarcopenia, and NLR, were independently associated with RFS. In the test set, the preoperative risk score exhibited a c-index of 0.741, which outperformed the predictive accuracy of pathological tumor staging (c-index of 0.673, p = 0.021) at various time points. The preoperative risk score effectively stratified patients into low and high-risk groups.

CONCLUSION

The developed preoperative risk scoring system demonstrated the ability to predict RFS following curative resection in GC patients.

Autophagy induced by Helicobacter Pylori infection can lead to gastric cancer dormancy, metastasis, and recurrence: new insights

According to the findings of recent research, Helicobacter Pylori (H. pylori) infection is not only the primary cause of gastric cancer (GC), but it is also linked to the spread and invasion of GC through a number of processes and factors that contribute to virulence. In this study, we discussed that H. pylori infection can increase autophagy in GC tumor cells, leading to poor prognosis in such patients. Until now, the main concerns have been focused on H. pylori's role in GC development. According to our hypothesis, however, H. pylori infection may also lead to GC dormancy, metastasis, and recurrence by stimulating autophagy. Therefore, understanding how H. pylori possess these processes through its virulence factors and various microRNAs can open new windows for providing new prevention and/or therapeutic approaches to combat GC dormancy, metastasis, and recurrence which can occur in GC patients with H. pylori infection with targeting autophagy and eradicating H. pylori infection.

Albumin hydrogels for repeated capture of drugs from the bloodstream and release into the tumor

Despite the efficacy of hydrogels for consistently delivering drugs to targeted areas (primarily tumors), these systems face challenges such as initial burst release, non-refillable drugs, and a lack of dosage control. To address these issues, a novel strategy has been developed to capture and release drugs from the bloodstream, thereby overcoming the limitations of traditional hydrogels. In this study, an innovative albumin hydrogel system was developed through a bioorthogonal reaction using azide-modified albumin and 4-arm PEG-DBCO. This system can repeatedly capture and release drugs over prolonged periods. Inspired by albumin-drug binding in vivo, this hydrogel can be injected intratumorally and acts as a reservoir for capturing drugs circulating in the bloodstream. Drugs captured in hydrogels are released slowly and effectively delivered to tumors through a "capture and release process." Both the in vitro and in vivo results indicated that the hydrogel effectively captured and released drugs, such as indocyanine green and doxorubicin, over repeated cycles without compromising the activity of the drugs. Moreover, implanting the hydrogel at surgical sites successfully inhibited tumor recurrence through its drug capture-release capability. These findings establish the albumin hydrogel system as a promising capture-release platform that leverages drug-binding affinity to effectively deliver drugs to tumors, offering potential advancements in cancer treatment and post-surgery recurrence prevention.

Implication of KDR Polymorphism rs2071559 on Therapeutic Outcomes and Safety of Postoperative Patients with Gastric Cancer Who Received S-1-Based Adjuvant Chemotherapy: A Real-World Exploratory Study

Objective

Regimens of S-1-based adjuvant chemotherapy are of great significance in attenuating recurrence risk in postoperative patients with gastric cancer (GC). Kinase insert-domain receptor (KDR) gene plays an essential role in tumor growth and metastasis. This study aimed to investigate the implication of KDR genotyping on the therapeutic outcomes of patients with gastric cancer (GC) who received S-1-based adjuvant chemotherapy.

Methods

A total of 169 postoperative GC with pathological staging of II and III and no metastasis who received S-1-based adjuvant chemotherapy were included retrospectively. Peripheral blood specimens were collected and prepared for KDR genotyping and KDR mRNA expression. Correlation between KDR genotype status and prognosis was performed using Kaplan-Meier survival analysis, and multivariate analysis was ultimately adopted using Cox regression analysis.

Results

Median disease-free survival (DFS) of the 169 patients with GC was 5.1 years [95% confidence interval (CI): 4.25-5.95] and median overall survival (OS) was 6.7 years (95% CI: 5.44-7.96). Rs2071559 was located at the upstream region, and the prevalence among 169 patients with GC was as follows: AA genotype in 104 cases (61.5%), AG genotype in 57 cases (33.7%), and GG genotype in 8 cases (4.7%), yielding a minor allele frequency of 0.22, which was consistent with Hardy-Weinberg equilibrium (P=0.958). Median DFS of patients with AA and AG/GG genotypes was 6.0 years and 4.0 years, respectively (P=0.002). Additionally, patients with the AA genotype had longer OS than those with the AG/GG genotype [median OS: not reached (NR) vs 5.5 years, P=0.011]. Additionally, KDR mRNA expression was significantly higher in patients with the AG/GG genotype than that in those with the AA genotype (P<0.001).

Conclusion

Rs2071559 in KDR gene might be a promising biomarker for evaluating the recurrence risk and OS of patients with GC who received S-1-based adjuvant chemotherapy. This conclusion should be confirmed in randomized clinical trials.

Recent Advances in Sentinel Node Navigation Surgery for Early Gastric Cancer

Maintaining the postoperative quality of life (QOL) while ensuring curability without overtreatment is important in the treatment of early gastric cancer. Postoperative QOL is anticipated to be maintained through minimally invasive function-preserving gastrectomy in early gastric cancer. The concept of the sentinel lymph node (SN) basin is essential to maintain the curability of early gastric cancer using minimally invasive function-preserving gastrectomy. However, additional resection after surgery is difficult to perform in gastric cancer. Thus, the SN basin theory is important. Recently, a multicenter randomized phase III trial in South Korea (SENORITA trial) proved that laparoscopic sentinel node navigation surgery (LSNNS) for stomach preservation results in better postoperative QOL compared with standard gastrectomy in patients with early gastric cancer. LSNNS contributes to patients' QOL based on the concept that curability is not impaired. A multicenter nonrandomized phase III trial is ongoing in Japan, and oncologic safety is expected to be demonstrated. LSNNS has been established as a treatment option for selected patients with early gastric cancer, and its application will become widespread in the future.

CircRNA circ-MYBL2 absorbs precursor miR-92b in the nucleus to suppress its role in enhancing gastric cancer cell proliferation

BACKGROUND

MM-associated circular RNA (Circ-MYBL2), a circular RNA (circRNA), participates in cancer biology. However, its role in gastric cancer (GC) is unclear. In this study, circ-MYBL2 was predicted to interact with precursor microRNA-92b (miR-92b). We then analyzed the role of circ-MYBL2 in GC and explored its crosstalk with miR-92b.

METHODS

In this research Circ-MYBL2 and miR-92b (mature and precursor) accumulation was determined using reverse transcription polymerase chain reaction (RT-qPCR). The involvement of circ-MYBL2 in the maturation of miR-92b was analyzed using overexpression assays. The subcellular location of circ-MYBL2 was determined using nuclear fractionation assay. The binding of precursor miR-92b to circ-MYBL2 was analyzed through RNA-RNA pulldown assay. The role of circ-MYBL2 and miR-92b in GC cell proliferation was studied with BrdU assay.

RESULTS

We found that GC tissues exhibited increased mature miR-92b levels but decreased precursor miR-92b and circ-MYBL2 levels. Circ-MYBL2 was detected in both the nucleus and cytoplasm in GC cells, and it directly interacted with precursor miR-92b. Moreover, circ-MYBL2 overexpression increased precursor miR-92b expression and decreased mature miR-92b level. Furthermore, miR-92b (mature) increased GC cell proliferation, and circ-MYBL2 decreased GC cell proliferation and suppressed the effect of miR-92b on GC cell proliferation.

CONCLUSIONS

Circ-MYBL2 may absorb precursor miR-92b in the nucleus to suppress its role in promoting gastric cancer cell proliferation.

LRRC8A influences the growth of gastric cancer cells via the p53 signaling pathway

BACKGROUND

Leucin-rich repeat containing protein A (LRRC8A), a component of the volume-regulated anion channel (VRAC), is activated by cell swelling and mediates regulatory volume decrease. We previously reported the expression of and important roles for several ion transporters in various gastrointestinal cancers, which have potential as novel targets for cancer treatment; however, the significance of LRRC8A in gastric cancer (GC) remains unclear.

MATERIALS AND METHODS

Knockdown experiments were performed by transfecting human GC cell lines with LRRC8A siRNA. Gene expression was then assessed using microarray analysis. Samples from 132 patients with GC were subjected to immunohistochemistry (IHC) for LRRC8A, and its relationships with clinicopathological factors and prognosis were examined.

RESULTS

The knockdown of LRRC8A suppressed the proliferation and movement of cells and enhanced apoptosis. The results of the microarray analysis showed the up- or down-regulated expression of genes related to the p53 signaling pathway (JNK, p53, p21, Bcl-2, and FAS) in LRRC8A-knockdown cells. IHC revealed a correlation between the expression of LRRC8A and the pT status (p = 0.015), and multivariate analysis identified the strong expression of LRRC8A as an independent prognostic factor for 5-year survival in GC patients (p = 0.0231).

CONCLUSIONS

The present results indicate that LRRC8A functions as a mediator of and/or biomarker for GC.

Taxane-based versus platinum-based chemotherapy in early recurrent gastric cancer after radical surgery with S-1 adjuvant chemotherapy: A multi-institutional retrospective analysis

AIM

This study aimed to compare the efficacy of taxane-based and platinum-based regimens in patients with early recurrent gastric cancer after radical surgery with S-1 adjuvant chemotherapy.

METHODS

The medical records of 118 patients from six institutes with early recurrent stage II/III gastric cancer, who developed recurrence during adjuvant S-1 or within 6 months after completion of adjuvant therapy between January 2006 and December 2017, were retrospectively analyzed. Patients treated with second line chemotherapy were enrolled and followed to the end of December 2019. The impact of two regimens, taxane-based (n = 46) versus platinum-based (n = 31), on treatment outcome were evaluated using multivariate analysis.

RESULTS

Median overall survival was 9.0 months and median progression-free survival was 4.1 months. No difference was observed in overall survival between taxane-based and platinum-based regimens (P = 0.64). Although not significant, the response rate of platinum-based regimens was better than that of taxane-based regimens (16% vs. 6.5%, P = 0.26). Multivariate analysis identified performance status (P = 0.040), multiorgan metastases (P = 0.029), and undifferentiated histological type (P = 0.018) as independent poor prognostic factors. In undifferentiated histological type, multiorgan metastases (P = 0.013) and taxane-based regimens (P = 0.018) were independent prognosis factors characterized by multivariate analysis. Conversion rate to third-line chemotherapy or more was 51% in undifferentiated histological type and 65% in differentiated histological type (P = 0.26).

CONCLUSION

Platinum-based regimens may be recommended for undifferentiated early recurrent gastric cancer after S-1 adjuvant chemotherapy.

Clinical TNM staging for esophageal, gastric, and colorectal cancers in the era of neoadjuvant therapy: A systematic review of the literature

AIM

Clinical staging is vital for selecting appropriate candidates and designing neoadjuvant treatment strategies for advanced tumors. The aim of this review was to evaluate diagnostic abilities of clinical TNM staging for gastrointestinal, gastrointestinal cancers.

METHODS

We conducted a systematic review of recent publications to evaluate the accuracy of diagnostic modalities on gastrointestinal cancers. A systematic literature search was performed in PubMed/MEDLINE using the keywords "TNM staging," "T4 staging," "distant metastases," "esophageal cancer," "gastric cancer," and "colorectal cancer," and the search terms used in Cochrane Reviews between January 2005 to July 2020. Articles focusing on preoperative diagnosis of: (a) depth of invasion; (b) lymph node metastases; and (c) distant metastases were selected.

RESULTS

After a full-text search, a final set of 55 studies (17 esophageal cancer studies, 26 gastric cancer studies, and 12 colorectal cancer studies) were used to evaluate the accuracy of clinical TNM staging. Positron emission tomography-computed tomography (PET-CT) and/or magnetic resonance imaging (MRI) were the best modalities to assess distant metastases. Fat and fiber mode of CT may be useful for T4 staging of esophageal cancer, CT was a partially reliable modality for lymph node staging in gastric cancer, and CT combined with MRI was the most reliable modality for liver metastases from colorectal cancer.

CONCLUSION

The most reliable diagnostic modality differed among gastrointestinal cancers depending on the type of cancer. Therefore, we propose diagnostic algorithms for clinical staging for each type of cancer.

Comparison of neoadjuvant chemotherapy followed by surgery vs. surgery alone for locally advanced gastric cancer: a meta-analysis

BACKGROUND

The neoadjuvant chemotherapy is increasingly used in advanced gastric cancer, but the effects on safety and survival are still controversial. The objective of this meta-analysis was to compare the overall survival and short-term surgical outcomes between neoadjuvant chemotherapy followed by surgery (NACS) and surgery alone (SA) for locally advanced gastric cancer.

METHODS

Databases (PubMed, Embase, Web of Science, Cochrane Library, and Google Scholar) were explored for relative studies from January 2000 to January 2021. The quality of randomized controlled trials and cohort studies was evaluated using the modified Jadad scoring system and the Newcastle-Ottawa scale, respectively. The Review Manager software (version 5.3) was used to perform this meta-analysis. The overall survival was evaluated as the primary outcome, while perioperative indicators and post-operative complications were evaluated as the secondary outcomes.

RESULTS

Twenty studies, including 1420 NACS cases and 1942 SA cases, were enrolled. The results showed that there were no significant differences in overall survival (P = 0.240), harvested lymph nodes (P = 0.200), total complications (P = 0.080), and 30-day post-operative mortality (P = 0.490) between the NACS and SA groups. However, the NACS group was associated with a longer operation time (P < 0.0001), a higher R0 resection rate (P = 0.003), less reoperation (P = 0.030), and less anastomotic leakage (P = 0.007) compared with SA group.

CONCLUSIONS

Compared with SA, NACS was considered safe and feasible for improved R0 resection rate as well as decreased reoperation and anastomotic leakage. While unbenefited overall survival indicated a less important effect of NACS on long-term oncological outcomes.

Long-Term Outcomes of Neoadjuvant Chemotherapy in Locally Advanced Gastric Cancer/Esophagogastric Junction Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Neoadjuvant chemotherapy (NAC) has been defined as any preoperative chemotherapy scheme aiming to reduce tumor staging and to control preoperative micrometastasis, which has been extensively used as a treatment for resectable gastric cancer. However, its effect on the long-term survival of patients with locally advanced gastric cancer (AGC) or esophagogastric junction cancer (EGC) remains unknown.

OBJECTIVE

This study aimed at investigating the long-term efficacy of NAC in locally AGC/EGC.

METHODS

The following databases were searched for articles published from their inception up to April 2020: PubMed, Web of Science, EBSCO, and Cochrane library. The primary outcomes were overall survival (OS) and progression-free survival (PFS).

RESULTS

A total of 19 articles were included in this meta-analysis, with a total of 4,446 patients. The results showed that NAC increased the patients' 3-year OS (HR, 0.56; 95%CI, 0.21-0.91; P<0.001), 3-year PFS (HR, 0.76; 95%CI, 0.66-0.87; P<0.001), 5-year OS (HR, 0.71; 95% CI, 0.64-0.78; P<0.001), and 5-year PFS (HR, 0.70; 95% CI, 0.61-0.79; P<0.001) respectively. Besides, subgroup analysis showed that Asian countries have benefited significantly from NAC (HR, 0.65; 95%CI, 0.55-0.74; P<0.001), and other countries have also benefited (HR, 0.79; 95%CI, 0.68-0.89; P<0.001).

CONCLUSIONS

Compared with adjuvant chemotherapy and surgery alone, NAC can improve the long-term survival outcomes (OS and PFS) of patients with resectable AGC or EGC.

DHA Abolishes the Detrimental Effect of Docetaxel on Downregulation of the MICA via Decreasing the Expression Level of MicroRNA-20a in Gastric Cancer

BACKGROUND

MHC class I chain-related protein A (MICA) is a membrane glycoprotein expressed abnormally on some malignant cells including gastric cancer (GC) cell and elicits anti-tumor immune responses. Downregulation of MICA expression could lead to immune-evasion of cancer cells.

OBJECTIVE(S)

In this study, we aimed to investigate the effect of docosahexaenoic acid (DHA) and docetaxel alone or in combination on the expression level of MICA and its regulating microRNA (miRNA), miR-20a in MKN45 GC cell line.

METHOD(S)

MKN45 GC cell line was cultured and MTT assay was performed to determine IC50 of docetaxel. Cells were treated by 18.5 μM docetaxel and 100 μM DHA. After that, RNA extraction and cDNA synthesis were done and the expression level of MICA and miR-20a were determined by quantitative real-time PCR for both treated and untreated cell lines.

RESULTS

Our findings showed less downregulation of the expression level of MICA by the combination of docetaxel/DHA (5.34-fold) compared with docetaxel (45.45-fold) and DHA (55.55-fold). Consistently, combination therapy led to the more downregulation of the expression level of the miR-20a (5.20-fold) in comparison to docetaxel (2.38-fold) and DHA (1.60-fold).

CONCLUSION(S)

As an unwanted effect of docetaxel therapy in GC, downregulation of MICA expression could lead to weak anti-tumor immune responses. By increasing the expression level of MICA, combination therapy of docetaxel with DHA would be useful to overcome this side effect.

Oxidative stress activates NORAD expression by H3K27ac and promotes oxaliplatin resistance in gastric cancer by enhancing autophagy flux via targeting the miR-433-3p

Oxaliplatin resistance undermines its curative effects on cancer and usually leads to local recurrence. The oxidative stress induced DNA damage repair response is an important mechanism for inducing oxaliplatin resistance by activating autophagy. ELISA is used to detect target genes expression. TMT-based quantitative proteomic analysis was used to investigate the potential mechanisms involved in NORAD interactions based on GO analysis. Transwell assays and apoptosis flow cytometry were used for biological function analysis. CCK-8 was used to calculate IC50 and resistance index (RI) values. Dual-luciferase reporter gene assay, RIP and ChIP assays, and RNA pull-down were used to detect the interaction. Autophagy flux was evaluated using electron microscope and western blotting. Oxidative stress was enhanced by oxaliplatin; and oxaliplatin resistance gastric cancer cell showed lower oxidative stress. TMT labeling showed that NORAD may regulate autophagy flux. NORAD was highly expressed in oxaliplatin-resistant tissues. In vitro experiments indicate that NORAD knockdown decreases the RI (Resistance Index). Oxaliplatin induces oxidative stress and upregulates the expression of NORAD. SGC-7901 shows enhanced oxidative stress than oxaliplatin-resistant cells (SGC-7901-R). NORAD, activated by H3K27ac and CREBBP, enhanced the autophagy flux in SGC-7901-R to suppress the oxidative stress. NORAD binds to miR-433-3p and thereby stabilize the ATG5- ATG12 complex. Our findings illustrate that NORAD, activated by the oxidative stress, can positively regulate ATG5 and ATG12 and enhance the autophagy flux by sponging miR-433-3p. NORAD may be a potential biomarker for predicting oxaliplatin resistance and mediating oxidative stress, and provides therapeutic targets for reversing oxaliplatin resistance.

Prognostic value of CEA/CA72-4 immunohistochemistry in combination with cytology for detecting tumor cells in peritoneal lavage in gastric cancer

Aim: To study the value and efficiency of CEA/CA72-4 immunohistochemistry in detecting free tumor cells from peritoneal lavage, in order to provide reliable lab information for subsequent intraperitoneal chemotherapy. Methods: A total of 112 progressive gastric cancer patients were enrolled from Oct. 2016 to Oct 2017, who were pathologically diagnosed as gastric cancer after surgery. Peritoneal lavage was respectively collected during operation. Cytology and CEA/CA72-4 immunohistochemistry of peritoneal lavage samples was performed. Overall survival and recurrence free survival was analyzed. Results: Cytology showed 16 positive cases (14.29%), CEA immunohistochemistry showed 29 positive cases (25.89%), CA72-4 immunohistochemistry showed 33 positive cases (29.46%). McNemar's test showed significant difference in positivity between cytology (CY+) and CEA/CA72-4 immunohistochemistry (IHC+). Kappa test showed consistency between immunohistochemistry of CEA and CA72-4 with cytology. Patients with CY+/IHC+ had the poorest overall survival (OS) as well as recurrence free survival (RFS), followed by those with CY+ or IHC+, while those with CY-/IHC- had higher OS and RFS. The differences of OS and RFS in IHC+ group were worse than that in IHC- group. Kaplan-Meier analysis showed that positive CEA/CA72-4 IHC revealed poorer prognosis than the negative cases. Conclusions: Due to the limitation of cytology, combination of cytology and immunohistochemistry appears to be more efficient for predicting prognosis of progressive gastric cancer.

Perioperative chemotherapy for advanced gastric cancer - results from a tertiary-care hospital in Germany

BACKGROUND

Neoadjuvant/perioperative chemotherapy is the recommended treatment for advanced stages of gastric cancer (> T2, N+) before tumour resection in many European guidelines. However, there is no consensus as to whether perioperative chemotherapy is as effective in distal as in proximal tumours, in addition to a relevant uncertainty concerning appropriate treatment modalities for elderly patients.

AIM

To investigate the role of perioperative chemotherapy in advanced gastric cancer in patients from a German tertiary clinic with respect to efficacy, localisation, and age.

METHODS

We performed a retrospective analysis of 158 patients from our clinic with adenocarcinoma of the stomach or the gastroesophageal junction who underwent resection between 2008 and 2016. The data were evaluated particularly in relation to patient age, tumour site, and perioperative therapy.

RESULTS

Administration of perioperative chemotherapy did not lead to a significant survival advantage in our study population. The 5-year survival rates were 40% for patients who received perioperative chemotherapy and 29% for the group without perioperative chemotherapy (P = 0.125). Our patients were on average distinctly older than patients in most of the published randomised controlled trials. Patients elder than 75 years received perioperative chemotherapy far less frequently. Patients with a proximal tumour received perioperative chemotherapy much more often.

CONCLUSION

This analysis reconfirms our previous data concerning the effectiveness of perioperative chemotherapy for advanced gastric cancer. There is reasonable doubt that the quality of the existing randomized controlled trials is sufficient to generally justify perioperative chemotherapy in patients with advanced gastric cancer independent of tumour localization or age.

Establishment of Peritoneal and Hepatic Metastasis Mouse Xenograft Models Using Gastric Cancer Cell Lines

BACKGROUND/AIM

Establishment of mouse xenograft models is necessary for oncological research and depends on the characteristics of the cell lines and the immune system of the host. In this study, we describe the development of mouse xenograft models using human gastric cancer (GC) cell lines.

MATERIALS AND METHODS

MKN1 stably-expressing luciferase (MKN1-Luc), N87, KATO III, MKN45 stably-expressing luciferase (MKN45-Luc), NUGC4, and OCUM-1 human GC cell lines were injected intraperitoneally into mice to establish peritoneal metastasis models. MKN45-Luc were injected into subcutaneously implanted spleen, and MKN1-Luc and MKN45-Luc were injected directly into the portal veins of mice for the establishment of hepatic metastasis models.

RESULTS

Peritoneal metastasis was formed after implantation of MKN1-Luc, N87, KATO III, MKN45-Luc, and NUGC4 in nude mice, but not formed in OCUM-1 even in NOD/SCID mice. After intrasplenic injection of MKN45-Luc, we found no hepatic metastasis formation. We identified hepatic metastasis formation after direct injection of MKN45-Luc and MKN1-Luc into the portal veins of NOD/SCID mice.

CONCLUSION

Peritoneal and hepatic metastasis mouse xenograft models were successfully established using several human GC cell lines.

Evaluation of Systemic Inflammatory Response and Nutritional Biomarkers as Predictive Factors in Patients with Recurrent Gastric Cancer

BACKGROUND

The present study sought to evaluate host-related factors as predictors in patients receiving chemotherapy for recurrent advanced gastric cancer.

METHODS

Sixty-three patients were enrolled in the study and received chemotherapy for recurrent gastric cancer at the Kochi Medical School from 2008 to 2015. Clinicopathological information and systemic inflammatory response data were obtained retrospectively to investigate associations between baseline cancer-related prognostic variables and survival outcomes.

RESULTS

The median survival time was significantly higher for patients with a Glasgow prognostic score (GPS) of 0 compared to a GPS of 1 or 2 (18.2 vs. 7.1 months; p = 0.006), and for patients in the normal range for carbohydrate antigen-125 (CA125) compared to higher levels (17.9 vs. 4.1 months; p = 0.003). There was no significant influence on overall survival by age, gender, disease status, metastatic site, time to recurrence, carcinoembryonic antigen level, CA19-9 level, prognostic nutrition index, or neutrophil to lymphocyte ratio according to the results of the univariate log-rank tests. Multivariate survival analysis identified a GPS of 1 or 2 (hazard ratio, 3.520; 95% confidence interval, 1.343-9.227; p = 0.010) and a high CA125 level (hazard ratio, 3.135; 95% confidence interval, 1.276-7.697; p = 0.013) as significant independent predictors associated with a poorer prognosis in the studied group of cancer patients.

CONCLUSIONS

A GPS of 1 or 2 and a high level of CA125 are independent predictors of a poorer prognosis in patients receiving chemotherapy for recurrent gastric cancer.

Optimization of perioperative approaches for advanced and late stages of gastric cancer: clinical proposal based on literature evidence, personal experience, and ongoing trials and research

BACKGROUND

The high incidence of gastric cancer (GC) and paradoxical high prevalence of advanced stage GC, amounting to around 2/3 at time of diagnosis, have urged doctors and researchers around the world not only to ameliorate the detection rate of GC at early stages but also to optimize the clinical management of GC at advanced stages.

CONTENT

We hereby recommend a more goal-oriented multimodality approach with objectives to increase survival rate and improve survival status. Based on precision and accurate clinical staging at diagnosis, we suggest that advanced stage GC (AGC) patients should be channeled into different treatment plans according to their disease status where they can be subjected to comprehensive measures involving chemo, radio, immunological, or target therapies depending on the pathophysiological behavior of their tumor. Patients assessed as potentially resectable cT4N + M0 can undergo neoadjuvant chemotherapy with intent of tumor downsizing and downgrading followed by surgery with intraoperative hyperthermic intraperitoneal chemotherapy (HIPEC) to decrease the incidence of peritoneal dissemination due to surgical trauma and adjuvant chemotherapy and radiation in cases of bulky nodal metastasis. In cases with distal metastasis, conversion therapy is recommended with the possibility of surgery of curative intent in case of favorable response. The options of alternate treatment options such as trans-catheter arterial chemoembolization (TACE) for limited liver lesions or neoadjuvant intraperitoneal plus systemic chemotherapy (NIPS) for peritoneal carcinomatosis have to be negotiated. With surgery as the cornerstone for cancer treatment, there is acknowledgment of the significance of perioperative comprehensive approaches but there has not been some consensus guiding clinical application. Henceforth, in this review, based on past literature, current guidelines and ongoing clinical trials, we have shared a proposal of the current treatment modalities in practice for the advanced stages of gastric cancer.

CONCLUSION

Even though surgery is the golden standard of radical cancer treatment, clinical reality shows that without proper perioperative management, patients undergoing radical resections manifest high rates of recurrence and metastasis. Hence, in this review, we have outlined a clinical agenda to optimize the management of advanced stage GC with objective to improve survival outcome and quality of life of patients.

Circular RNA circMAN2B2 promotes growth and migration of gastric cancer cells by down-regulation of miR-145

Background

CircMAN2B2 is a newly discovered circRNA that has been found to be an oncogene in lung cancer and glioma. The present study was designed to reveal the role of circMAN2B2 in gastric carcinoma (GC).

Methods

qRT‐PCR method was utilized to examine circMAN2B2 expression in GC tissues and paracancerous tissues. Next, circMAN2B2 expression in SNU‐16 and AGS cells was silenced by transfection. CCK‐8 assay, colony formation assay, flow cytometer, Transwell assay, and Western blot were conducted for testing cell phenotype changes. Further, the downstream genes and signaling were uncovered by qRT‐PCR and Western blot.

Results

As relative to paracancerous tissues, circMAN2B2 was high‐expressed in GC tissues. Silence of circMAN2B2 clearly declined SNU‐16 and AGS cells viability, survival, migration but enhanced apoptosis. Meanwhile, silence of circMAN2B2 induced the cleavage of caspases (−3 and −9), down‐regulation of MMPs (−2 and −9), and up‐regulation of miR‐145. The impacts of circMAN2B2 silence toward SNU‐16 and AGS cells were attenuated by miR‐145 silence. Moreover, circMAN2B2 silence deactivated PI3K, AKT while activated JNK through regulating miR‐145.

Conclusion

This work presented the oncogenic function of circMAN2B2 in GC cells growth and migration. CircMAN2B2 exerted its function possibly through regulating miR‐145 as well as PI3K/AKT and JNK pathways.

Abacavir induces the transcriptional activity of YY1 and other oncogenic transcription factors in gastric cancer cells

Yin Yang 1 (YY1) is a ubiquitous transcription factor with both transcriptional activating and repressing functions. Targeting YY1 is considered as a potential therapeutic strategy for several malignancies. Telomerase Reverse Transcriptase (TERT) is also considered as a potential target for cancer therapeutics. To enable the large-scale screening and identification of potential YY1 targeting drugs, a gastric cancer cell line-based drug screening assay was developed. In a YY1 targeted drug repurpose screen, abacavir sulfate, a nucleoside analog reverse transcriptase inhibitor, known to target TERT was identified to show the feature of activating YY1 mediated transcription. We further explored i) the molecular targets of abacavir, ii) activation pattern of pathways regulated by abacavir in gastric tumors, and iii) therapeutic potential of abacavir for gastric cancer cells. Oncogenic signaling pathways like MYC, HIF1-α, ERK, WNT, E2F, NFκB and NRF1/2 were also found to be highly activated by abacavir. Abacavir was found to have less impact on the viability of gastric cancer cells. Across gastric tumors, we observed the co-activation of TERT, alternative lengthening of telomere (ALT), DNA repair, and the oncogenic pathways MYC, E2F/DP1, ERK, YY1, HIF1α, and NFκB specific gene-sets, in a subset of gastric tumors. The observed connectivity among TERT, DNA repair, and multiple oncogenic pathways indicate the need for the development of combinatorial therapeutics for the gastric tumors with the activated TERT.

Essential updates 2017/2018: Recent topics in the treatment and research of gastric cancer in Japan

Recent developments in diagnostic technology, accumulated clinical effort and established evidence have boosted early detection and drastically improved early and long-term outcomes of gastric cancer. However, gastric cancer continues to be one of the most aggressive and life-threatening malignancies among all cancers and is a global health problem. Between January 2017 and December 2018, various fascinating reports of managements and research were published, including the new 15th Japanese Classification of Gastric Carcinoma reflecting the 8th American Joint Committee on Cancer/Union for International Cancer Control (AJCC/UICC) tumor, node and metastasis (TNM) classification (October 2017) and the new Gastric Cancer Treatment Guidelines version 5 (January 2018). Moreover, pivotal molecular features of gastric cancer were clarified by the worldwide cancer genome project, and various treatment targets and biomarkers such as circulating DNAs and microRNAs were detected. Novel treatment options using programmed cell death protein 1 immune checkpoint inhibitors have been started. In this review, we summarize the recent topics of classification, guidelines, and clinical and basic research in order to bring new insights to gastric cancer treatment.

Combination of apatinib mesylate and second-line chemotherapy for treating gastroesophageal junction adenocarcinoma

Objective

To investigate the safety and efficacy of acitinib mesylate combined with chemotherapy in the treatment of patients with gastroesophageal junction adenocarcinoma.

Methods

A total of 119 patients with gastroesophageal junction adenocarcinoma were enrolled and randomized into an experimental group (n = 60) and a control group (n = 59). Both groups were treated with a combination of taxane, irinotecan and fluorouracil, while the experimental group also received acitinib mesylate. The clinical efficacy, survival time and adverse reactions of patients in two groups were recorded and analyzed.

Results

The total remission rate in the experimental group and the control group was 15.79% and 3.23%, respectively; the disease control rate was 73.68% and 54.84%, respectively; and progression-free survival was 3.72 months (1–13.5 months) and 3.04 months (1–6 months), respectively. Overall survival was 13.66 months (5–24 months) and 10.08 months (6.5–19.5 months), in the experimental group and the control group, respectively. In addition, the incidence of adverse events in the experimental group was significantly lower than that in the control group.

Conclusion

Apatinib mesylate combined with chemotherapy for the treatment of patients with gastroesophageal junction adenocarcinoma was safe and effective, with improved survival benefit compared with control.

Cancer-associated fibroblasts-derived IL-8 mediates resistance to cisplatin in human gastric cancer

Chemoresistance remains the major obstacle to achieve optimal prognosis in gastric cancer patients, and the underlying molecular mechanisms of cancer-associated fibroblasts (CAFs) in gastric cancer chemoresistance remain poorly understood. We identified the high pretherapeutical serum IL-8 level in gastric cancer patients was associated with poor response to platinum-based therapy, and it increased gradually during neoadjuvant chemotherapy and it decreased after radical surgery. Immunohistochemistry assays showed that IL-8 was highly expressed in gastric cancer tissues in chemoresistant patients, and located in CAFs. Primary CAFs produced more IL-8 than the corresponding normal fibroblasts, and human stomach fibroblast line Hs738 secreted more IL-8 after co-cultured with conditioned media from AGS or MGC-803 cells. IL-8 increased the IC50 of cisplatin (CDDP) in AGS or MGC-803 in vitro. Simultaneously, IL-8 treatment enhanced the expression of PI3K, phosphorylated-AKT (p-AKT), phosphorylated-IKb (p-IKb), phosphorylated-p65 (p-p65) and ABCB1, and ABCB1 and p-p65 were overexpressed in tumor tissues of chemoresistant patients. Collectively, CAFs derived IL-8 promotes chemoresistance in human gastric cancer via NF-κB activation and ABCB1 up-regulation. Our study provides a novel strategy to improve the chemotherapeutical efficacy and the prognosis of gastric cancer.

Overexpression of YEATS4 contributes to malignant outcomes in gastric carcinoma

YEATS domain containing 4 (YEATS4) has functions of chromatin modification and transcriptional regulation and is in a gene-amplified region (12q13) in various human cancers. In this study, we tested whether YEATS4 acts as a cancer-promoting gene through its activation/overexpression in gastric cancer (GC). We analyzed 5 GC cell lines and 135 primary tumor samples of GC, which were curatively resected in our hospital. Overexpression of the YEATS4 protein was frequently detected in GC cell lines (5/5 cell lines, 100%) and primary GC tumor tissues (32/135 cases, 23.7%). Knockdown of YEATS4 inhibited proliferation, migration and invasion of GC cells through NOTCH2 down-regulation in a TP53 mutation-independent manner, and induced apoptosis in wild-type TP53 GC cells. Moreover, knockdown of YEATS4 improved chemosensitivity for CDDP and L-OHP. Overexpression of YEATS4 protein significantly correlated with more aggressive lymphatic invasion, larger tumor size, deeper tumor depth, positive lymph node metastasis and recurrence. Patients with YEATS4-overexpressing tumors had a lower overall survival rate than those with non-expressing tumors. Multivariate analysis demonstrated that YEATS4 was independently associated with poor outcomes. These findings suggest that YEATS4 plays a pivotal role in tumor malignant potential through its overexpression and highlight its usefulness as a prognostic factor and potential therapeutic target in GC.

Recent updates in perioperative chemotherapy and recurrence pattern of gastric cancer

Gastrectomy with D2 lymph node dissection has become the global standard procedure for locally advanced gastric cancer to maximally reduce locoregional recurrence. In East Asia, based on the evidence of the ACTS‐GC and the CLASSIC trials, postadjuvant chemotherapy with S‐1 monotherapy or capecitabine and oxaliplatin after curative D2 gastrectomy is the current standard strategy. However, approximately 20% to 30% of patients still develop distant recurrence even after these postadjuvant chemotherapies, especially in those with pathological stage III disease. This review summarizes recent (2008‐2018) evidence on the benefits of adjuvant therapy for locally advanced gastric cancer. JACRO GC‐07, a Phase III trial, recently showed a superior 3‐year recurrence‐free survival of the S‐1 plus docetaxel regimen in comparison to S‐1 monotherapy for patients with pathological stage III gastric cancer after curative D2 gastrectomy. With regard to recent new evidence on neoadjuvant strategy, JCOG0501, a Phase III trial, did not show any superiority in 3‐year overall survival (OS) of additional neoadjuvant chemotherapy with S‐1/cisplatin over postadjuvant S‐1 monotherapy in scirrhous type gastric cancer. Further clinical trials of neoadjuvant chemotherapy are ongoing to improve the poor prognosis for gastric cancer with extensive lymph node metastases. These trials could lead to new evidence for improved treatment of gastric cancer in the near future.