Adaptation of STIM1 structure-function relationships for optogenetic control of calcium signaling.

In cellular contexts, the oscillation of calcium ions (Ca2+) is intricately linked to various physiological processes, such as cell proliferation, metabolism, and survival. Stromal interaction molecule 1 (STIM1) proteins form a crucial regulatory component in the store-operated calcium entry process. The structural attributes of STIM1 are vital for its functionality, encompassing distinct domains situated in the endoplasmic reticulum lumen and the cytoplasm. The intraluminal domain enables the timely detection of diminishing Ca2+ concentrations, prompting structural modifications that activate the cytoplasmic domain. This activated cytoplasmic domain undergoes conformational alterations and engages with membrane components, opening a channel that facilitates the influx of Ca2+ from the extracellular environment. Given its multiple domains and interaction mechanisms, STIM1 plays a foundational role in cellular biology. This review focuses on the design of optogenetic tools inspired by the structure and function of STIM1. These tools offer a groundbreaking approach for studying and manipulating intracellular Ca2+ signaling with precise spatiotemporal control. We further explore the practical applications of these tools, spanning fundamental scientific research, clinical studies, and their potential for translational research.

Atlas of Metastatic Gastric Cancer Links Ferroptosis to Disease Progression and Immunotherapy Response.

BACKGROUND & AIMS: Metastases from gastric adenocarcinoma (GAC) lead to high morbidity and mortality. Developing innovative and effective therapies requires a comprehensive understanding of the tumor and immune biology of advanced GAC. Yet, collecting matched specimens from advanced, treatment-naïve patients with GAC poses a significant challenge, limiting the scope of current research, which has focused predominantly on localized tumors. This gap hinders deeper insight into the metastatic dynamics of GAC. METHODS: We performed in-depth single-cell transcriptome and immune profiling on 68 paired, treatment-naïve, primary metastatic tumors to delineate alterations in cancer cells and their tumor microenvironment during metastatic progression. To validate our observations, we conducted comprehensive functional studies both in vitro and in vivo, using cell lines and multiple patient-derived xenograft and novel mouse models of GAC. RESULTS: Liver and peritoneal metastases exhibited distinct properties in cancer cells and dynamics of tumor microenvironment phenotypes, supporting the notion that cancer cells and their local tumor microenvironments co-evolve at metastatic sites. Our study also revealed differential activation of cancer meta-programs across metastases. We observed evasion of cancer cell ferroptosis via GPX4 up-regulation during GAC progression. Conditional depletion of Gpx4 or pharmacologic inhibition of ferroptosis resistance significantly attenuated tumor growth and metastatic progression. In addition, ferroptosis-resensitizing treatments augmented the efficacy of chimeric antigen receptor T-cell therapy. CONCLUSIONS: This study represents the largest single-cell dataset of metastatic GACs to date. High-resolution mapping of the molecular and cellular dynamics of GAC metastasis has revealed a rationale for targeting ferroptosis defense in combination with chimeric antigen receptor T-cell therapy as a novel therapeutic strategy with potential immense clinical implications.

Pretreatment Pan-Immune-Inflammation Value (PIV) in Predicting Therapeutic Response and Clinical Outcomes of Neoadjuvant Immunochemotherapy for Esophageal Squamous Cell Carcinoma.

PURPOSE: The pan-immune-inflammation value (PIV), which reflects the balance between the host immune and inflammatory status, is a readily available index for evaluating cancer outcomes. Until now, however, no study has demonstrated the clinical response of PIV to neoadjuvant immunochemotherapy (NICT) in esophageal squamous cell carcinoma (ESCC). METHODS: This retrospective study included 218 patients with ESCC who underwent NICT. The relationship between PIV and therapeutic response (pathological complete response [PCR]) and clinical outcomes (overall survival [OS] and disease-free survival [DFS]) was examined. Cox proportional, hazard-regression analyses and the Kaplan-Meier method were used for survival analyses. Recursive partitioning analysis (RPA) was used to establish a novel risk stratification model. RESULTS: Sixty-six patients (30.3%) achieved PCR after NICT. Using PCR as the endpoint of interest, patients were compared in groups based on the optimal threshold. PIV was closely related to PCR (odds ratio [OR] 0.311, 95% confidence interval [CI] 0.140-0.690, P = 0.004). Compared with patients in the low PIV cohort, patients with high PIV had worse 3-year OS (58.7% vs. 83.6%, P < 0.001) and DFS (51.9% vs. 79.1%, P < 0.001). PIV was an independent predictor of OS (hazard ratio [HR] 2.364, 95% CI 1.183-4.724, P = 0.015) and DFS (HR 1.729, 95% CI 1.026-2.913, P = 0.040). Three risk groups with varied DFS and OS were staged by using an RPA method, and the prognostication accuracy was considerably improved. CONCLUSIONS: Pretreatment PIV can predict the therapeutic efficacy of NICT for ESCC. Because of better prognostic stratification, pretreatment PIV is a novel, sensitive, and effective indicator in ESCC receiving NICT. The prognostic results of PIV need to be verified in additional prospective studies.

Development and validation of nomogram for predicting early recurrence after radical gastrectomy of gastric cancer.

BACKGROUND: After radical surgery, early detection of recurrence and metastasis is a crucial factor in enhancing the prognosis and survival of patients with gastric cancer (GC). Therefore, assessing the risk of recurrence in gastric cancer patients and determining the timing for postoperative recurrence is crucial. METHODS: The clinicopathological data of 521 patients with recurrent gastric cancer, who underwent radical gastrectomy at Zhejiang Cancer Hospital between January 2010 and January 2017, were retrospectively analyzed. These patients were randomly divided into two groups: a training group (n = 365) and a validation group (n = 156). In the training set, patients were further categorized into early recurrence (n = 263) and late recurrence (n = 102) groups based on a 2-year boundary. Comparative analyses of clinicopathological features and prognoses were conducted between these two groups. Subsequently, a nomogram for predicting early recurrence was developed and validated. RESULTS: In this study, the developed nomogram incorporated age, serous infiltration, lymph node metastasis, recurrence mode, and the tumour marker CA19-9. In the training cohort, the area under the curve (AUC value) was 0.739 (95% CI, 0.682-0.798), with a corresponding C-index of 0.739. This nomogram was subsequently validated in an independent validation cohort, yielding an AUC of 0.743 (95% CI, 0.652-0.833) and a C-index of 0.743. Furthermore, independent risk factors for prognosis were identified, including age, absence of postoperative chemotherapy, early recurrence, lymph node metastasis, abdominal metastasis, and vascular cancer embolus. CONCLUSION: Independent risk factors for gastric cancer recurrence following radical surgery were utilized to construct a nomogram for predicting early relapse. This nomogram effectively assesses the risk of recurrence, aids in treatment decision-making and follow-up planning in clinical settings, and demonstrated strong performance in the validation cohort.

Efficient plasma metabolic fingerprinting as a novel tool for diagnosis and prognosis of gastric cancer: a large-scale, multicentre study.

OBJECTIVE: Metabolic biomarkers are expected to decode the phenotype of gastric cancer (GC) and lead to high-performance blood tests towards GC diagnosis and prognosis. We attempted to develop diagnostic and prognostic models for GC based on plasma metabolic information. DESIGN: We conducted a large-scale, multicentre study comprising 1944 participants from 7 centres in retrospective cohort and 264 participants in prospective cohort. Discovery and verification phases of diagnostic and prognostic models were conducted in retrospective cohort through machine learning and Cox regression of plasma metabolic fingerprints (PMFs) obtained by nanoparticle-enhanced laser desorption/ionisation-mass spectrometry (NPELDI-MS). Furthermore, the developed diagnostic model was validated in prospective cohort by both NPELDI-MS and ultra-performance liquid chromatography-MS (UPLC-MS). RESULTS: We demonstrated the high throughput, desirable reproducibility and limited centre-specific effects of PMFs obtained through NPELDI-MS. In retrospective cohort, we achieved diagnostic performance with areas under curves (AUCs) of 0.862-0.988 in the discovery (n=1157 from 5 centres) and independent external verification dataset (n=787 from another 2 centres), through 5 different machine learning of PMFs, including neural network, ridge regression, lasso regression, support vector machine and random forest. Further, a metabolic panel consisting of 21 metabolites was constructed and identified for GC diagnosis with AUCs of 0.921-0.971 and 0.907-0.940 in the discovery and verification dataset, respectively. In the prospective study (n=264 from lead centre), both NPELDI-MS and UPLC-MS were applied to detect and validate the metabolic panel, and the diagnostic AUCs were 0.855-0.918 and 0.856-0.916, respectively. Moreover, we constructed a prognosis scoring system for GC in retrospective cohort, which can effectively predict the survival of GC patients. CONCLUSION: We developed and validated diagnostic and prognostic models for GC, which also contribute to advanced metabolic analysis towards diseases, including but not limited to GC.

Prognostic significance of inflammatory and nutritional markers in perioperative period for patients with advanced gastric cancer.

BACKGROUND: It has been reported that inflammatory and nutritional markers are related to prognosis in numerous malignancies. The present study analyzed the significance of these markers' alterations during neoadjuvant chemotherapy in the long-term outcomes in patients with advanced gastric cancer. METHODS: A retrospective review was performed of 437 advanced gastric cancer patients who underwent a neoadjuvant chemotherapy (NACT) regimen followed by surgical treatment. Inflammatory and nutritional markers measured from the blood samples collected from the patients before the first neoadjuvant chemotherapy and after the last neoadjuvant chemotherapy were used for analysis. Statistical analysis, including Mann-Whitney U or chi-square tests, the Kaplan-Meier method and Cox multivariate analysis, were performed to analyze the predictive value of these markers for overall survival outcomes (OS). RESULTS: Most biomarkers, including lymphocyte, leucocyte, neutrophil, monocyte, platelet, LMR, PLR, SII, CRP, CAR, hemoglobulin and albumin levels, changed during NACT (P <  0.05). After separately grouping the patients based on the normal range of hematologic indexes and the change rate (α) of systemic inflammatory and nutritional markers by the cutoff value derived from X-tile (P <  0.05), we found that differentiation, TRG, pre-NACT BMI, pre-NACT platelet counts, post-NACT lymphocyte counts, the change in lymphocyte counts, change in platelet counts and LMR(α), PLR(α), SII(α), and CAR(α) were associated with OS. Multivariate analysis revealed that PLR (α) > - 19% was correlated with a 3.193-fold (95% CI: 2.194-4.649) higher risk of death (P <  0.001) than others. CONCLUSION: NACT could significantly change several inflammatory and nutritional markers in the perioperative period; the platelet counts before NACT, and the change in lymphocytes during NACT truly correlated with long-term outcomes among patients with advanced gastric cancer. The systemic inflammatory marker PLR may be a reliable marker for the prediction of prognosis.

Dual inhibition of MYC and SLC39A10 by a novel natural product STAT3 inhibitor derived from Chaetomium globosum suppresses tumor growth and metastasis in gastric cancer.

Gastric cancer remains one of the most common deadly diseases and lacks effective targeted therapies. In the present study, we confirmed that the signal transducer and activator of transcription 3 (STAT3) is highly expressed and associated with a poor prognosis in gastric cancer. We further identified a novel natural product inhibitor of STAT3, termed XYA-2, which interacts specifically with the SH2 domain of STAT3 (Kd= 3.29 µM) and inhibits IL-6-induced STAT3 phosphorylation at Tyr705 and nuclear translocation. XYA-2 inhibited the viability of seven human gastric cancer cell lines with 72-h IC50 values ranging from 0.5 to 0.7 µΜ. XYA-2 at 1 µΜ inhibited the colony formation and migration ability of MGC803 (72.6% and 67.6%, respectively) and MKN28 (78.5% and 96.6%, respectively) cells. In the in vivo studies, intraperitoneal administration of XYA-2 (10 mg/kg/day, 7 days/week) significantly suppressed 59.8% and 88.8% tumor growth in the MKN28-derived xenograft mouse model and MGC803-derived orthotopic mouse model, respectively. Similar results were obtained in a patient-derived xenograft (PDX) mouse model. Moreover, XYA-2 treatment extended the survival of mice bearing PDX tumors. The molecular mechanism studies based on transcriptomics and proteomics analyses indicated that XYA-2 might exert its anticancer activity by synergistically inhibiting the expression of MYC and SLC39A10, two downstream genes of STAT3 in vitro and in vivo. Together, these findings suggested that XYA-2 may be a potent STAT3 inhibitor for treating gastric cancer, and dual inhibition of MYC and SLC39A10 may be an effective therapeutic strategy for STAT3-activated cancer.

Targeting KRAS mutant cancers: from druggable therapy to drug resistance.

Kirsten Rat Sarcoma Viral Oncogene Homolog (KRAS) is the most frequently mutated oncogene, occurring in a variety of tumor types. Targeting KRAS mutations with drugs is challenging because KRAS is considered undruggable due to the lack of classic drug binding sites. Over the past 40 years, great efforts have been made to explore routes for indirect targeting of KRAS mutant cancers, including KRAS expression, processing, upstream regulators, or downstream effectors. With the advent of KRAS (G12C) inhibitors, KRAS mutations are now druggable. Despite such inhibitors showing remarkable clinical responses, resistance to monotherapy of KRAS inhibitors is eventually developed. Significant progress has been made in understanding the mechanisms of drug resistance to KRAS-mutant inhibitors. Here we review the most recent advances in therapeutic approaches and resistance mechanisms targeting KRAS mutations and discuss opportunities for combination therapy.

Targeting E2 ubiquitin-conjugating enzyme UbcH5c by small molecule inhibitor suppresses pancreatic cancer growth and metastasis.

BACKGROUND: Pancreatic cancer is one of the most lethal cancers worldwide. The IAPs function as E3 ubiquitin ligases and contribute to pancreatic cancer initiation, progression, and metastasis. Although IAP-targeted therapies have been developed and shown anticancer efficacy in preclinical settings, none of them has been approved yet. METHODS: Transcriptome data from public datasets were used to analyze the correlation of IAPs and E2s, and the biological function of E2 UbcH5c in pancreatic cancer. A structure-based virtual screen was used to identify UbcH5c inhibitor, and surface plasmon resonance analysis and cellular thermal shift assays were employed to evaluate the binding affinity. The anticancer activities were demonstrated through in vitro and in vivo assays, while the related mechanisms were explored through transcriptomic and proteomic analyses and confirmed by western blot, immunofluorescence, and qRT-PCR. RESULTS: UbcH5c is positively correlated with the expression of IAPs in pancreatic cancer. We further found that UbcH5c is overexpressed and associated with a poor prognosis in pancreatic cancer. We identified a small-molecule UbcH5c inhibitor, termed DHPO, which directly bound to UbcH5c protein. DHPO inhibited cell viability and colony formation, induced apoptosis, and suppressed migration and invasion of pancreatic cancer cells in vitro. The compound inhibited UbcH5c-mediated IκBα degradation and NF-κB activation, which is critical for its anticancer activity. Furthermore, DHPO suppressed the tumor growth and metastasis in two orthotopic pancreatic tumor mouse models. CONCLUSIONS: These results indicated that inhibiting UbcH5c is a novel and effective strategy for treating pancreatic cancer and DHPO represents a new class of UbcH5c inhibitor and may be further developed as an anti-pancreatic cancer therapeutic agent.

Discovery of benzochalcone derivative as a potential antigastric cancer agent targeting signal transducer and activator of transcription 3 (STAT3).

Gastric cancer remains a significant health burden worldwide. In continuation of our previous study and development of effective small molecules against gastric cancer, a series of benzochalcone analogues involving heterocyclic molecules were synthesised and biologically evaluated in vitro and in vivo. Among them, the quinolin-6-yl substituted derivative KL-6 inhibited the growth of gastric cancer cells (HGC27, MKN28, AZ521, AGS, and MKN1) with a submicromolar to micromolar range of IC50, being the most potent one in this series. Additionally, KL-6 significantly inhibited the colony formation, migration and invasion, and effectively induced apoptosis of MKN1 cells in a concentration-dependent manner. The mechanistic study revealed that KL-6 could concentration-dependently suppress STAT3 phosphorylation, which may partly contribute to its anticancer activity. Furthermore, in vivo antitumour study on the MKN1 orthotopic tumour model showed that KL-6 effectively inhibited tumour growth (TGI of 78%) and metastasis without obvious toxicity. Collectively, compound KL-6 may support the further development of candidates for gastric cancer treatment.

Preoperative chemotherapy combined with para-aortic lymph node dissection has clinical value in the treatment of gastric cancer with para-aortic lymph node metastases.

BACKGROUND: Lymph node metastases often occur in advanced gastric cancer, with some patients presenting with metastases in the para-aortic lymph nodes. There are persistent Controversies about the benefit of para-aortic lymph node dissection (PAND). Our purpose is to probe whether PAND following preoperative chemotherapy had any clinical significance in individuals with PALNs in gastric cancer. MATERIAL AND METHODS: To retrospectively analyze the clinical data of 86 gastric cancer patients (40 in the D2 + PAND group and 46 in the D2 group) who attended the abdominal surgery department of Zhejiang Cancer Hospital between September 1, 2008, and July 30, 2018. RESULTS: In the D2 + PAND group (40 cases), the average number of lymph nodes cleared per case was 4.3 in group 16 (16a2, 16b1), and the postoperative pathology confirmed lymph node positivity in 16 cases, with a metastasis rate of 40%. The median overall survival times were 63 and 34 months for the patients in the D2 + PAND group and D2 group, respectively. The 3-year overall survival (OS) compared to the D2 group (D2 + PAND 69.1% vs. D2 50%, P = 0.012) and a statistically significant difference in 3-year disease-free survival (DFS) (D2 + PAND 69.6% vs. D2 38.3%, P = 0.007). Lymph node dissection extent and recurrence of para-aortic lymph nodes were independent prognostic variables for the patients. The recurrence rate was reduced in the D2 + PAND group compared to the D2 group (D2 + PAND 7.5% vs. D2 26.1%, p = 0.023). CONCLUSIONS: For patients with gastric cancer whose imaging suggests metastasis in the para-aortic lymph nodes, preoperative chemotherapy combined with PAND is an effective and safe treatment that may benefit patient survival.

Efficacy analysis of Cheng's GIRAFFE reconstruction after proximal gastrectomy for adenocarcinoma of esophagogastric junction.

Objective: Reconstruction of the digestive tract for adenocarcinoma of esophagogastric junction (AEG) is in dispute. This study evaluated Cheng's gastric tube interposition esophagogastrostomy with reconstruction of His angle and fundus (Cheng's GIRAFFE anastomosis) in laparoscopic/open proximal gastrectomy for Siewert type II AEG, which was performed at Zhejiang Cancer Hospital and the First Affiliated Hospital of Zhejiang Chinese Medical University. Here, we discuss the preliminary results of gastric emptying and anti-reflux. Methods: From a retrospective database, 74 patients with advanced Siewert type II AEG underwent curative proximal gastrectomy with GIRAFFE anastomosis, and their gastric emptying and anti-reflux outcomes were evaluated by the Reflux Disease Questionnaire (RDQ) score, nuclide gastric emptying, 24-h impedance-pH monitoring and gastroscopy. Results: Seventy-four patients successfully completed proximal partial gastrectomy with Cheng's GIRAFFE esophagogastric anastomosis. RDQ score six months after the operation was 2.2±2.5. Results of nuclide gastric emptying examinations showed that the gastric half-emptying time was 67.0±21.5 min, the 1-h residual rate was (52.2±7.7)%, the 2-h residual rate was (36.4±5.1)%, and the 3-h residual rate was (28.8±3.6)%; 24-h impedance-pH monitoring revealed that the mean DeMeester score was 5.8±2.9. Reflux esophagitis was observed by gastroscopy in 7 patients six months after surgery. Conclusions: Cheng's GIRAFFE anastomosis is safe and feasible for Siewert type II AEG.

Deep Targeted Sequencing and Its Potential Implication for Cancer Therapy in Chinese Patients with Gastric Adenocarcinoma.

INTRODUCTION: Gastric cancer (GC) has a high incidence and mortality rate, especially in East Asians, and about 90% of GCs are adenocarcinomas. Histological and etiological heterogeneity and ethnic diversity make molecular subtyping of GC complicated, thus making it difficult to determine molecular division systems and standard treatment modalities. Limited cohorts from South Korea, Singapore, Australia, and Japan have been studied; however, the mutational landscape of gastric adenocarcinomas in Chinese patients is still unknown. METHODS: We performed a targeted sequencing panel focusing on cancer-related genes and tumor-associated microorganisms of 529 gastric adenocarcinoma samples with matched blood controls. We identified 449 clinically relevant gene mutations. RESULTS: Approximately 47.1% of Chinese patients with GC harbored at least one actionable mutation. The top somatic mutations were TP53, ARID1A, LRP1B, PIK3CA, ERBB2, CDH1, KRAS, FAT4, CCNE1, and KMT2D. Truncation mutations of ARID1A, KMT2D, RNF43, TGFBR2, and CIC occurred in patients with high tumor mutational burden. Gene amplifications of ERBB2, CCNE1, CDK12, and CCND1 were detected in patients with low tumor mutational burden. Pathway analysis revealed common gene alterations in the Wnt and PI3K/Akt signaling pathways. The ratio of patients with high microsatellite instability was significantly lower than other cohorts, and high microsatellite instability and Epstein-Barr virus (EBV)-positive features seemed mutually inclusive in Chinese patients with GC. In 44 (8.3%) patients, 45 germline mutations were identified, among which SPINK1 mutations, all SPINK1 c.194 + 2T > C, were present in 15.9% (7/44) of patients. Microorganisms found in Chinese patients with GC included Helicobacter pylori, EBV, hepatitis B virus, and human papillomavirus types 16 and 18. CONCLUSION: Identification of varied molecular features by targeted next-generation sequencing provides more insight into patient stratification and offers more possibilities for both targeted therapies and immunotherapies of Chinese patients with GC. IMPLICATIONS FOR PRACTICE: This study investigated the genomic alteration profile of 529 Chinese patients with gastric adenocarcinoma by deep targeting sequencing, which might be the largest Chinese cohort on the genomic research of gastric adenocarcinoma up to now.

Adjuvant albumin-bound paclitaxel combined with S-1 vs. oxaliplatin combined with capecitabine after D2 gastrectomy in patients with stage III gastric adenocarcinoma: a phase III multicenter, open-label, randomized controlled clinical trial protocol.

BACKGROUND: Surgery is the only treatment option for operable gastric cancer. The CLASSIC and ACTS-GC studies showed that the 5-year overall survival (OS) of patients with stage III gastric cancer undergoing D2 gastrectomy is still very low. Whether adjuvant nanoparticle albumin-bound paclitaxel (nab-paclitaxel) combined chemotherapy is more effective than the XELOX standard adjuvant chemotherapy in patients with stage III gastric cancer has not been confirmed. METHODS: This is a multicenter, open-label, phase III clinical study. In this trial, 616 patients with locally advanced stage III gastric cancer that underwent curative D2 radical surgery and achieved R0 are planned to be included. Patients will be randomized 1:1 to nab-paclitaxel combined with S-1 (AS) vs. oxaliplatin combined with capecitabine (XELOX). XELOX group: Patients assigned to the XELOX group received eight 3-week cycles of oral capecitabine (1000 mg/m2) twice daily on days 1-14 of each cycle plus intravenous oxaliplatin 130 mg/m2 on day 1 of each cycle. AS group: AS group received eight 3-week cycles of oral S-1 (80-120 mg) (< 1.25 m2, 40 mg; 1.25 to < 1.5 m2, 50 mg; and > 1.5 m2, 60 mg) twice daily on days 1-14 plus intravenous nab-paclitaxel 120 mg/m2 on days 1 and 8 of each cycle. The primary endpoint was the 3-year disease-free survival (3-year-DFS) defined as the time from randomisation to the time of recurrence of the original gastric cancer, development of a new gastric cancer, or death from any cause. The secondary endpoints were the overall survival, (defined as the time from the date of randomisation to date of death from any cause) and safety (any adverse event). DISCUSSION: Compared with previous studies, this study includes nab-paclitaxel based on S-1 adjuvant chemotherapy, which is expected to achieve better efficacy and lower toxicity than the standard treatment. This study is the first clinical study to evaluate the safety and efficacy of nab-paclitaxel combined with S-1 in patients with stage III gastric cancer after D2 radical resection. TRIAL REGISTRATION: This clinical trial has been registered with ClinicalTrials.gov, registration number: NCT04135781 , on October 20th, 2019.

p-MEK expression predicts prognosis of patients with adenocarcinoma of esophagogastric junction (AEG) and plays a role in anti-AEG efficacy of Huaier.

The incidence rate of adenocarcinoma of the esophagogastric junction (AEG) is increasing worldwide with poor prognosis and unclear pathogenesis. Trametes robiniophila Murr. (Huaier), a traditional Chinese medicine has been used in the clinical treatment of a variety of solid tumors, including AEG. However, its anticancer components and molecular mechanisms are still unclear. In our previous studies, we have found that Huaier n-butanol extract (HBE) shows the most potent anticancer activity among different extracts. In the present study, we aimed to investigate the clinical relevance of p-MEK expression in AEG patients and the role of the MEK/ERK signaling pathway in the anti-AEG efficacy of HBE in vitro and in vivo. We herein demonstrate that p-MEK expression in AEG tissues was significantly higher than that in paracancerous tissues and correlated with a poor prognosis in AEG patients. We further found that HBE inhibited the colony formation, migration, and invasion in AEG cell lines in a concentration-dependent manner in vitro. HBE also suppressed the growth of AEG xenograft tumors without causing any host toxicity in vivo. Mechanistically, HBE caused the inactivation of the MEK/ERK signaling pathway by dephosphorylating MEK1 at S298, ERK1 at T202, and ERK2 at T185 and modulating the expression of EMT-related proteins. In summary, our results demonstrate that the high expression of p-MEK may be an independent factor of poor prognosis in patients with AEG. The clinically used anticancer drug Huaier may exert its anti-AEG efficacy by inhibiting the MEK/ERK signaling pathway.

Medicinal chemistry strategies to discover P-glycoprotein inhibitors: An update.

The presence of multidrug resistance (MDR) in malignant tumors is one of the primary causes of treatment failure in cancer chemotherapy. The overexpression of the ATP binding cassette (ABC) transporter, P-glycoprotein (P-gp), which significantly increases the efflux of certain anticancer drugs from tumor cells, produces MDR. Therefore, inhibition of P-gp may represent a viable therapeutic strategy to overcome cancer MDR. Over the past 4 decades, many compounds with P-gp inhibitory efficacy (referred to as first- and second-generation P-gp inhibitors) have been identified or synthesized. However, these compounds were not successful in clinical trials due to a lack of efficacy and/or untoward toxicity. Subsequently, third- and fourth-generation P-gp inhibitors were developed but dedicated clinical trials did not indicate a significant therapeutic effect. In recent years, an extraordinary array of highly potent, selective, and low-toxicity P-gp inhibitors have been reported. Herein, we provide a comprehensive review of the synthetic and natural products that have specific inhibitory activity on P-gp drug efflux as well as promising chemosensitizing efficacy in MDR cancer cells. The present review focuses primarily on the structural features, design strategies, and structure-activity relationships (SAR) of these compounds.

Cisplatin resistance in gastric cancer cells is involved with GPR30-mediated epithelial-mesenchymal transition.

Cisplatin is the major chemotherapeutic drug in gastric cancer, particularly in treating advanced gastric cancer. Tumour cells often develop resistance to chemotherapeutic drugs, which seriously affects the efficacy of chemotherapy. GPR30 is a novel oestrogen receptor that is involved in the invasion, metastasis and drug resistance of many tumours. Targeting GPR30 has been shown to increase the drug sensitivity of breast cancer cells. However, few studies have investigated the role of GPR30 in gastric cancer. Epithelial-mesenchymal transition (EMT) has been shown to be associated with the development of chemotherapeutic drug resistance. In this study, we demonstrated that GPR30 is involved in cisplatin resistance by promoting EMT in gastric cancer. GPR30 knockdown resulted in increased sensitivity of different gastric cancer (GC) cells to cisplatin and alterations in the epithelial/mesenchymal markers. Furthermore, G15 significantly enhanced the cisplatin sensitivity of GC cells while G1 inhibited this phenomenon. In addition, EMT occurred when AGS and BGC-823 were treated with cisplatin. Down-regulation of GPR30 with G15 inhibited this transformation, while G1 promoted it. Taken together, these results revealed the role of GPR30 in the formation of cisplatin resistance, suggesting that targeting GPR30 signalling may be a potential strategy for improving the efficacy of chemotherapy in gastric cancer.

Overexpression of B7H5/CD28H is associated with worse survival in human gastric cancer.

Gastric cancer (GC) is a common malignancy with low 5-year overall survival (OS). Recently, immune therapy has been used to treat cancer. B7H5 and CD28H are novel immune checkpoint molecules. However, the prognostic value of B7H5/CD28H expression in patients with GC remains unclear. In this study, seventy-one patients diagnosed with GC were included in this study. Patients' GC tissues and matched adjacent tissue constructed a tissue microarray. The expression levels of B7H5 and CD28H were examined using immunohistochemistry. Correlations between the expression of B7H5 and CD28H and the clinical data were evaluated. We found that the expression of B7H5 and CD28H (both P = .001) were higher in GC tumour tissues than in adjacent noncancerous tissues. B7H5/CD28H expression acted as an independent predictive factor in the OS of patients with GC. High expression of B7H5 and CD28H predicted poor outcome. Patients in the B7H5+CD28H+ group had a lower 5-year OS compared with patients in the B7H5-CD28- group (4.5% vs 55.6%, P = .001). A significant difference was found in the 5-year OS between patients in the B7H5+CD28H- and B7H5+CD28H+ groups (33.5% vs 4.5%, P = .006). However, there was no correlation between B7H5 and CD28H expression (P = .844). Therefore, B7H5 and CD28H expression are up-regulated in GC and are independent prognostic factors for overall survival in patients with GC. Although there was no correlation between B7H5 and CD28H expression, high expression of B7H5 and CD28H predicts poor prognosis, especially when both are highly expressed.

Long non-coding RNAs towards precision medicine in gastric cancer: early diagnosis, treatment, and drug resistance.

Gastric cancer is a deadly disease and remains the third leading cause of cancer-related death worldwide. The 5-year overall survival rate of patients with early-stage localized gastric cancer is more than 60%, whereas that of patients with distant metastasis is less than 5%. Surgical resection is the best option for early-stage gastric cancer, while chemotherapy is mainly used in the middle and advanced stages of this disease, despite the frequently reported treatment failure due to chemotherapy resistance. Therefore, there is an unmet medical need for identifying new biomarkers for the early diagnosis and proper management of patients, to achieve the best response to treatment. Long non-coding RNAs (lncRNAs) in body fluids have attracted widespread attention as biomarkers for early screening, diagnosis, treatment, prognosis, and responses to drugs due to the high specificity and sensitivity. In the present review, we focus on the clinical potential of lncRNAs as biomarkers in liquid biopsies in the diagnosis and prognosis of gastric cancer. We also comprehensively discuss the roles of lncRNAs and their molecular mechanisms in gastric cancer chemoresistance as well as their potential as therapeutic targets for gastric cancer precision medicine.

Neoadjuvant systemic and hyperthermic intraperitoneal chemotherapy combined with cytoreductive surgery for gastric cancer patients with limited peritoneal metastasis: a prospective cohort study.

BACKGROUND: There is no currently available treatment for peritoneal metastasis of gastric cancer. This phase II study aimed to evaluate the efficacy and safety of neoadjuvant systemic chemotherapy and hyperthermic intraperitoneal chemotherapy (HIPEC) combined with cytoreductive surgery (CRS) for the treatment of these patients. METHODS: Neoadjuvant chemotherapy comprised two cycles of HIPEC and four cycles of S-1 plus paclitaxel. HIPEC was administered intraperitoneally with paclitaxel (75 mg/m2). For systemic chemotherapy, paclitaxel was administered intravenously(150 mg/m2) on day 1, and S-1 was administered orally(80 mg/m2/day)on days 1-14 of a 3-week cycle. Another two cycles of HIPEC and four cycles of S-1 plus paclitaxel were administered after second diagnostic staging laparoscopy or CRS. The primary endpoints were treatment efficiency and safety; the secondary endpoint was 3-year overall survival (OS). RESULTS: A total of 40 patients were enrolled and 38 patients have been analyzed. Of these, 18 (47.4%) patients received neoadjuvant systemic chemotherapy, HIPEC and CRS (conversion therapy group), while 20 patients received only chemotherapy and HIPEC (palliative chemotherapy group). Median OS was markedly improved in the conversion therapy group (21.1 months, 95% confidence interval [CI] 16.7-25.6 months) in comparison with the palliative chemotherapy group(10.8 months, 95%CI 7.3-14.2 months, p = 0.002). After neoadjuvant systemic chemotherapy and HIPEC, a second laparoscopic exploration was performed, and the prognosis of patients with low peritoneal cancer index (PCI) (PCI < 6) was significantly better than that of patients with high PCI (PCI ≥ 6)(20.1 vs.11.3 months, p = 0.006). CONCLUSION: Neoadjuvant systemic chemotherapy and HIPEC combined with CRS is safe and feasible, and could potentially improve the prognosis of gastric cancer patients with limited peritoneal metastasis. However, further clinical trials are still warranted. TRIAL REGISTRATION: This study has been registered with ClinicalTrials.gov as NCT02549911 . Trial registration date: 15/09/2015.