Estrogen receptors as the novel therapeutic biomarker in non-small cell lung cancer

Although a wide range of studies have addressed the relationship between estrogen receptor(ER) expression and prognosis in non-small cell lung cancer(NSCLC), that relationship remains controversial. This is in large part because there is no consensus on the rate of ER expression in NSCLC or on the intracellular distribution of ER expression. This suggests that establishing the relationship between ER expression and prognosis will require standardization of the antibodies used as well as the definition of a positive response. For example, it is supposed from previous studies that ERs in the cytoplasm and nucleus have different relationships to prognosis than ERs in the cytoplasm. Moreover, ER signaling in NSCLC is known to be affected by aromatase, progesterone receptor and epidermal growth factor receptor mutation. However, there has been little functional analysis these mutants and subtypes. This review will focus on what is known about the role of ERs in NSCLC and whether ER can be a useful prognostic marker or therapeutic target in NSCLC.

Stage-specific localization of transforming growth factor β1 and β3 and their receptors during spermatogenesis in men

Aim: To investigate the stage-specific localization of transforming growth factor (TGF) β1 and β3 during spermatogenesis in adult human testis. Methods: The localization of TGFβ1 and β3 was investigated by immunohis tochemical staining method employing specific polyclonal antibodies. Results: Both TGFβ1 and β3 and their recep tors were preponderant in the Leydig celis. TGFβ1 could not be detected in the seminiferous tubules. TGFβ3 and TGFβ-Receptor (R) I were mainly seen in the elongated spermatids, while TGFβ-RⅡ in the pachytene spermatocytes and weak in the spermatogonia, spermatids and Sertoli celis. Only TGFβ-RⅡ was detected in the Sertoli celis. TGFβ3, TGFβ-RⅠ and TGFβ-RⅡ showed a staining pattern dependent upon the stages of the seminiferous epithelium cycle. Conclusion: TGFβ isoforms and their receptors are present in the somatic and germ celis of the adult human testis, suggesting their involvement in the regulation of spermatogenesis.

Expression of vascular endothelial growth factor and its receptors VEGFR-1 and 2 in gastrointestinal stromal tumors,leiomyomas and schwannomas

AIM： To investigate the role of vascular endothelial growth factor （VEGF/and its receptors VEGFR-1 and 2 in the growth and differentiation of gastrointestinal strornal tumors （GISTs）. METHODS： Thirty-three GISTs, 15 leiomyomas and 6 schwannomas were examined by immunohistochemistry in this study. RESULTS： VEGF protein was expressed in the cytoplasm of tumor cells, and VEGFRol and 2 were expressed both in the cytoplasm and on the membrane of all tumors. Irnrnunohistochernical staining revealed that 26 GISTs （78.8%）, 9 leiornyornas （60.0%） and 3 schwannornas （50.0%/were positive for VEGF; 24 GISTs （72.7%/, 12 leiornyornas （80.0%） and 4 schwannornas （66.7%） were positive for VEGFR-1; 30 GISTs （90.9%/, 5 leiornyornas （33.3%/and 4 schwannornas （66.7%） were positive for VEGFR-2. VEGFR-2 expression was statistically different between GISTs and leiomyomas （P 〈 0.0001）. However, there was no correlation between the expression of VEGF pathway componenets and the clinical risk categories. CONCLUSION： Our results suggest that the VEGF pathway may play an important role in the differentiation of GISTs, leiomyomas and schwannomas.

Expression of transforming growth factor β receptors in CCI_4, -induced cirrhotic liver in rats

Objective: To investigate the expression and the role of transforming growth factor 6 (TGF-β) receptors in CCI4 --Induced cirrhotic liver. Methods: In situ hybridization was used. Results: The TGF--β type I receptors mRNA was mainly expressed in Ito cells, endothelial cells and myofibroblasts. Only a few hepatocytes expressed it. However. the TGF-β type Ⅱ receptors was mostly localized in endothelial cells and Ito cells but few hepatocytes. The expression of mRNA of both the 2 types of receptors were significantly increased in the cirrhotic liver than in the control. Conclusion: The autocrine and paracrine effects of TGF-β on matrix production and activation of Ito cells might be an important factor of fibrogenesis in CCI4 cirrhotic ever.

Ontogeny of expression of transforming growth factor-βand its receptors and their possible relationship with scarless or scar-forming healing in human fetal and postnatal skins

Fetal eutaneous wounds that oeeur in earlygestation heal without sear formation.Althoughmueh work has been done to eharaeterize the roleof transforming growth

Growth factor receptors and related signalling pathways as targets for novel treatment strategies of hepatocellular cancer

Growth factors and their corresponding receptors are commonly overexpressed and/or dysregulated in many cancers including hepatocellular cancer （HCC）. Clinical trials indicate that growth factor receptors and their related signalling pathways play important roles in HCC cancer etiology and progression, thus providing rational targets for innovative cancer therapies. A number of strategies including monoclonal antibodies, tyrosine kinase inhibitors （＂small molecule inhibitors＂） and antisense oligonucleotides have already been evaluated for their potency to inhibit the activity and downstream signalling cascades of these receptors in HCC. First clinical trials have also shown that multi-kinase inhibition is an effective novel treatment strategy in HCC. In this respect sorafenib, an inhibitor of Raf-, VEGF- and PDGF-signalling, is the first multi-kinase inhibitor that has been approved by the FDA for the treatment of advanced HCC. Moreover, the serine-threonine kinase of mammalian target of rapamycin （mTOR） upon which the signalling of several growth factor receptors converge plays a central role in cancer cell proliferation, roTOR inhibition of HCC is currently also being studied in preclinical trials. As HCCs represent hypervascularized neoplasms, inhibition of tumour vessel formation via interfering with the VEGF/VEGFR system is another promising approach in HCC treatment. This review will summarize the current status of the various growth factor receptor-based treatment strategies and in view of the multitude of novel targeted approaches, the rationale for combination therapies for advanced HCC treatment will also be taken into account.

Expression of nerve growth factor precursor, mature nerve growth factor and their receptors during cerebral ischemia-reperfusion injury

We investigated nerve growth factor precursor （proNGF） and mature NGF expression in ischemic and non-ischemic cortices after cerebral ischemia-reperfusion injury. In both ischemic and non-ischemic cortices, proNGF was found to be present in the extracellular space and cytoplasm. In addition, mature NGF was expressed in extracellular space, but with a very low signal. In ischemic cortex only, proNGF was significantly decreased, reaching a minimal level at 1 day. Mature NGF was increased at 4 hours, then reached a minimal level at 3 days. The p75 neurotrophin receptor （p75NTR） was significantly decreased after ischemia, and increased at 3 days after ischemia. These results confirmed that proNGF was the predominant form of NGF during the pathological process of cerebral ischemia-repeffusion injury. In addition, our findings suggest that ischemic injury may influence the conversion of proNGF to mature NGF, and that proNGF/p75NTR may be involved in reperfusion injury.

Treatment of gastrointestinal neuroendocrine tumors with inhibitors of growth factor receptors and their signaling pathways: Recent advances and future perspectives

The limited efficacy of conventional cytotoxic treatment regimes for advanced gastrointestinal neuroendocrine cancers emphasizes the need for novel and more effective medical treatment options. Recent findings on the specific biological features of this family of neoplasms has led to the development of new targeted therapies, which take into account the high vascularization and abundant expression of specific growth factors and cognate tyrosine kinase receptors. This review will briefly summarize the status and future perspectives of antiangiogenic, mTOR- or growth factor receptor-based pharmacological approaches for the innovative treatment of gastrointestinal neuroendocrine tumors. In view of the multitude of novel targeted approaches, the rationale for innovative combination therapies, i.e. combining growth factor (receptor)-targeting agents with chemo- or biotherapeutics or with other novel anticancer drugs such as HDAC or proteasome inhibitors will be taken into account.

Expression of vascular endothelial growth factor and its two receptors in normal human endometrium

Objectives: We try to demonstrate the expression of vascular endothelial growthfactor (VEGF) and its receptors, flt-1 and KDR, in normal human emdometrium duringthe menstrual cycle.Methods: Immunohistochemical method was used to observe the expression ofVEGF and its two receptors in emdometrium throughout the normal menstrual cyclemeanwhile the isoforms of VEGF were also detected by Western blot analysis. The en-dothelial cells of micro-vessels were marked with Ⅷ factor antibody.Results: VEGF and its receptors existed in endometrial glandular, stromal and vas-cular endothelial cells of human endometrium. Their expressions were higher in the mid-secretory phase of menstrual cycle and highest at menstruation. VEGF121 and VEGF165were the predominant isoforms in normal human endometrium.Conclusion: The expression of VEGF and its two receptors showed cycle-dependentin human endometrium, probably involved in embryonic implantation and endometrialproliferation and differentiation.

Basic fibroblast growth factor increases the numbe of endogenous neural stem cells and inhibits the expression of amino methyl isoxazole propionic acid receptors in amyotrophic lateral sclerosis mice

This study aimed to investigate the number of amino methyl isoxazole propionic acid （AMPA） receptors and production of endogenous neural stem cells in the SOD1 G93AG1H transgenic mouse model of amyotrophic lateral sclerosis, at postnatal day 60 following administration of basic fibroblast growth factor （FGF-2）. A radioligand binding assay and immunohistochemistry were used to estimate the number of AMPA receptors and endogenous neural stem cells respectively. Results showed that the number of AMPA receptors and endogenous neural stem cells in the brain stem and sensorimotor cortex were significantly increased, while motor function was significantly decreased at postnatal days 90 and 120. After administration of FGF-2 into mice, numbers of endogenous neural stem cells increased, while expression of AMPA receptors decreased, whilst motor functions were recovered. At postnatal day 120, the number of AMPA receptors was negatively correlated with the number of endogenous neural stem cells in model mice and FGF-2-treated mice. Our experimental findings indicate that FGF-2 can inhibit AMPA receptors and increase the number of endogenous neural stem cells, thus repairing neural injury in amyotrophic lateral sclerosis mice.

Grade Dependent Expression of Growth Factor Receptors and Signaling Molecules in Breast Cancer

Growth factor signaling plays a key role in the growth and development of breast. Aberrant expression and activation of growth factors like insulin like growth factor-I (IGF-I) and epidermal growth factor (EGF) and their downstream signaling has been implicated in breast cancer. The deregulation of growth factor signaling is associated with increased proliferation and cell survival, decreased apoptosis, invasion, angiogenesis and metastasis. The aim of the present study is to survey the different signaling molecules involved in the IGF and EGF signaling pathways, and to find if there are any relationship between breast cancer and their levels and activation. Thirty-nine samples of breast cancer tissues (24 Grade II and 15 Grade III tumours) and sixteen normal breast tissue samples were collected. The expression of the receptors and signaling molecules were investigated using Western blot. IGF-IRβ, AR, pAkt, IKK-α and p38 are upregulated in cancer tissues in a grade depended manner. Further, Akt and β-catenin were also upregulated in cancer samples. Correlation analysis of signaling molecules revealed a disruption in their expression in cancer tissues. The present study shows that various signaling molecules are upregulated or activated in cancer tissues involving IGF-IR and Akt pathway. The expression of signaling molecules in the cancer tissues were deregulated when compared to the control samples. Thus, flawed expression and over activation of Akt pathway is seen in the breast cancer tissues.

Correlation between expression of two transforming growth factor-beta 1 receptors and microvascular density in a rat model of cerebral ischemia and reperfusion injury

The effects of transforming growth factor-β1 （TGF-β1） are currently controversial. Whether TGF-β1 promotes or inhibits revascularization under different conditions remains poorly understood. Based on previous studies, the current experiment established rat models of cerebral ischemia and reperfusion injury （IRI）, and demonstrated that pathological and functional damage was also increased after IRI. The most serious damage was observed at 3 days after reperfusion, at which time microvascular density fell to its lowest level. Soon afterwards, microvascular density increased, new collateral circulation was gradually established at 4 to 7 days after reperfusion, and pathological damage and neurological deficits were improved. TGF-β1, activin receptor-like kinase 5 （ALK5） mRNA and protein expression levels increased gradually over time. In contrast, ALK1 mRNA and protein expression decreased over the same period. A significant negative correlation was detected between microvascular density and expression of the ALK5 gene transcript. There was no correlation between microvascular density and ALK1 gene transcriptional expression following cerebral IRI in a rat model. These findings suggest that ALK5, rather than ALK1, is the critical receptor in the TGF-β1 signal pathways after cerebral IRI.

Angiogenic and FLT3 Receptors Expression in Acute Lymphoblastic Leukemia in Pediatric Age Group

Angiogenesis has an important role in pathophysiology of cancer. FMS-like tyrosine kinase 3 (FLT3) is implicated in hematopoietic malignancies. Their role in childhood acute lymphoblastic leukemia (ALL) pathogenesis needs more enlightenment. Expression of vascular endothelial growth factor receptor-1 and -2 (VEGFR-1 and -2), as well as FLT3 were assessed by flow cytometry in bone marrow (BM) blasts of 55 newly diagnosed children with ALL. Patients included B cell ALL (B-ALL) group (n = 41) and T cell ALL (T-ALL) group (n = 14). Comparison between groups revealed a significant increase in blasts percent (%) expressing FLT3 and FLT3 intensity detected in B-ALL group (p = 0.004 and p = 0.02, respectively). In B-ALL patients, a significant positive correlation was seen between blasts % expressing FLT3 and blasts percentage infiltrating BM (r = 0.405;p = 0.009), also positive correlation was seen between % of blasts expressing VEGFR-1 and VEGFR-2 (r = 0.704;p 0.001). In T-ALL group, blast % expressing FLT3 revealed significant positive correlations with blast % expressing VEGFR-1, and those expressing VEGFR-2 (r = 0.627;p = 0.016, and r = 0.654;p = 0.011, respectively). In addition, significant correlation was seen in blasts % expressing all;FLT3, VEGFR-1 and -2, with blasts % expressing stem cell marker CD34 (r = 0.826;p = 0.001, r = 0.596;p = 0.041, and r = 0.798;p = 0.002, respectively). Conclusion: Expression of VEGFR-1, VEGFR-2 and FLT3 were demonstrated and linked on leukemic blasts of ALL which highlights their role in pathogenesis. FLT3 expression plays a role in facilitating blasts proliferation in BM in B-ALL. FLT3, VEGFR-1 and -2 could be used in future profiling of CD34+ leukemic stem cell pool in T-ALL.

The expression of the products of IGF-Ⅱ,IGF-Ⅱ receptors and CSF-Ⅰ receptors in human primary hepatocellular carcinoma and juxtacancerous liver tissue

The expression of the products of IGF-Ⅱ,IGF-Ⅱ receptors(IGF-Ⅱ-R)and CSF-Ⅰ re-ceptors(CSF-Ⅰ-R)was observed in 17 cases of human primary hepatocellular carcinoma(PHC)and the juxtacancerous liver tissue with immunohistochemistry(ABC),Western blot and North-ern blot technique,It was found that the expression of IGF-Ⅱ,IGF-Ⅱ-R and CSF-Ⅰ-R was signif-icantly higher in PHC than in normal liver tissue and the expression of IGF-Ⅱ and IGF-Ⅱ-R wasremarkably higher in the juxtacancerous liver tissue from PHC patients than in PHC proper.Itwas noteworthy that the expression of IGF-Ⅱ in both the cancer proper and the juxtacancerousliver tissue was characterized by its fetal type.Besides,the expression of CSF-Ⅰ-R was signifi-cantly higher in PHC than in the juxtacancerous liver tissue.It is believed that the abnormal ex-pression of IGF-Ⅱ,IGF-Ⅱ-R and CSF-I-R in PHC and the juxtacaneerous liver tissue might berelated to the autocrine mechanism of human PHC.

PRaG 3.0 therapy for human epidermal growth factor receptor 2-positive metastatic pancreatic ductal adenocarcinoma:A case report

BACKGROUND Pancreatic ductal adenocarcinoma(PDAC)is a highly fatal disease with limited effective treatment especially after first-line chemotherapy.The human epidermal growth factor receptor 2(HER-2)immunohistochemistry(IHC)positive is associated with more aggressive clinical behavior and shorter overall survival in PDAC.CASE SUMMARY We present a case of multiple metastatic PDAC with IHC mismatch repair proficient but HER-2 IHC weakly positive at diagnosis that didn’t have tumor regression after first-line nab-paclitaxel plus gemcitabine and PD-1 inhibitor treatment.A novel combination therapy PRaG 3.0 of RC48(HER2-antibody-drug conjugate),radio-therapy,PD-1 inhibitor,granulocyte-macrophage colony-stimulating factor and interleukin-2 was then applied as second-line therapy and the patient had confirmed good partial response with progress-free-survival of 6.5 months and overall survival of 14.2 month.She had not developed any grade 2 or above treatment-related adverse events at any point.Percentage of peripheral CD8^(+) Temra and CD4^(+) Temra were increased during first two activation cycles of PRaG 3.0 treatment containing radiotherapy but deceased to the baseline during the maintenance cycles containing no radiotherapy.CONCLUSION PRaG 3.0 might be a novel strategy for HER2-positive metastatic PDAC patients who failed from previous first-line approach and even PD-1 immunotherapy but needs more data in prospective trials.

Efficacy and safety of dacomitinib as first-line treatment for advanced non-small cell lung cancer patients with epidermal growth factor receptor 21L858R mutation:A multicenter,case-series study in China

Objective:To provide real-world evidence for the application of first-line dacomitinib treatment for epidermal growth factor receptor(EGFR)21L858R mutant non-small cell lung cancer(NSCLC)patients in China and to explore the factors influencing the efficacy and safety.Methods:A longitudinal,consecutive case-series,multicenter study with mixed prospective and retrospective data was conducted.The primary endpoint was progression-free survival(PFS),and the secondary endpoints included duration of treatment(DOT),overall survival(OS),objective response rate(ORR),disease control rate(DCR)and safety.Results:A total of 155 EGFR 21L858R mutant patients treated with first-line dacomitinib were included.The median follow-up time for these patients was 20.4 months.Among 134 patients with evaluable lesions,the ORR was 70.9%and the DCR was 96.3%.The median PFS was 16.3[95%confidence interval(95%CI),13.7−18.9]months.Multivariate Cox regression analysis suggested that the baseline brain metastasis(BM)status[with vs.without BM:hazard ratio(HR),1.331;95%CI,0.720−2.458;P=0.361]and initial doses(45 mg vs.30 mg:HR,0.837;95%CI,0.427−1.641;P=0.604)did not significantly affect the median PFS.The median DOT was 21.0(95%CI,17.5−24.6)months and the median OS was not reached.Genetic tests were performed in 64 patients after progression,among whom 29(45.3%)patients developed the EGFR 20T790M mutation.In addition,among the 46 patients who discontinued dacomitinib treatment after progression,31(67.4%)patients received subsequent third-generation EGFR-tyrosine kinase inhibitors.The most common grade 3−4 adverse events were rash(10.4%),diarrhea(9.1%),stomatitis(7.1%)and paronychia(4.5%).The incidence of grade 3−4 rash was significantly higher in the 45 mg group than that in the 30 mg group(21.9%vs.7.5%,P=0.042).Conclusions:First-line dacomitinib treatment demonstrated promising efficacy and tolerable adverse events among EGFR 21L858R mutant NSCLC patients in China.

Inetetamab combined with S-1 and oxaliplatin as first-line treatment for human epidermal growth factor receptor 2-positive gastric cancer

BACKGROUND Patients with human epidermal growth factor receptor 2(HER2)-positive advanced gastric cancer have poor outcomes.Trastuzumab combined with chemotherapy is the first-line standard treatment for HER2-positive advanced gastric cancer.Inetetamab is a novel anti-HER2 drug,and its efficacy and safety in gastric cancer have not yet been reported.AIM To evaluate the efficacy and safety of the S-1 plus oxaliplatin(SOX)regimen combined with inetetamab as a first-line treatment for HER2-positive advanced gastric cancer.METHODS Thirty-eight patients with HER2-positive advanced gastric cancer or gastroeso-phageal junction adenocarcinoma were randomly divided into two groups:One group received inetetamab combined with the SOX regimen,and the other group received trastuzumab combined with the SOX regimen.After 4-6 cycles,patients with stable disease received maintenance therapy.The primary endpoints were progression-free survival(PFS)and overall survival(OS),and the secondary endpoints were the objective response rate,disease control rate,and adverse events(AEs).RESULTS Thirty-seven patients completed the trial,with 18 patients in the inetetamab group and 19 patients in the trastuzumab group.In the inetetamab group,the median PFS was 8.5 months,whereas it was 7.3 months in the trastuzumab group(P=0.046);this difference was significant.The median OS in the inetetamab group vs the trastuzumab group was 15.4 months vs 14.3 months(P=0.33),and the objective response rate was 50%vs 42%(P=0.63),respectively;these differences were not significant.Common AEs included leukopenia,thrombocytopenia,nausea,and vomiting.The incidence rates of grade≥3 AEs were 56%in the inetetamab group and 47%in the trastuzumab group(P=0.63),with no significant difference.CONCLUSION In the first-line treatment of HER2-positive advanced gastric cancer,inetetamab and trastuzumab showed comparable efficacy.The inetetamab group showed superior PFS,and both groups had good safety.

BIRC3 induces the phosphoinositide 3-kinase-Akt pathway activation to promote trastuzumab resistance in human epidermal growth factor receptor 2-positive gastric cancer

BACKGROUND Trastuzumab-targeted therapy is currently the standard of care for advanced human epidermal growth factor receptor 2(HER2)-positive gastric cancer.However,the emergence of resistance to trastuzumab poses significant challenges.AIM To identify the key genes associated with trastuzumab resistance.These results provide a basis for the development of interventions to address drug resistance and improve patient outcomes.METHODS High-throughput sequencing and bioinformatics were used to identify the differentially expressed pivotal gene BIRC3 and delineate its potential function and pathway regulation.Tumor samples were collected from patients with HER2-positive gastric cancer to evaluate the correlation between BIRC3 expression and trastuzumab resistance.We established gastric cancer cell lines with both highly expressed and suppressed levels of BIRC3,followed by comprehensive in vitro and in vivo experiments to confirm the involvement of BIRC3 in trastuzumab resistance and to elucidate its underlying mechanisms.RESULTS In patients with HER2-positive gastric cancer,there is a significant correlation between elevated BIRC3 expression in tumor tissues and higher T stage,tumor node metastasis stage,as well as poor overall survival and progressionfree survival.BIRC3 is highly expressed in trastuzumab-resistant gastric cancer cell lines,where it inhibits tumor cell apoptosis and enhances trastuzumab resistance by promoting the phosphorylation and activation of the phosphoinositide 3-kinase-Akt(PI3K-AKT)pathway in HER2-positive gastric cancer cells,both in vivo and in vitro.CONCLUSION This study revealed a robust association between high BIRC3 expression and an unfavorable prognosis in patients with HER2-positive gastric cancer.Thus,the high expression of BIRC3 stimulated PI3K-AKT phosphorylation and activation,stimulating the proliferation of HER2-positive tumor cells and suppressing apoptosis,ultimately leading to trastuzumab resistance.

Therapeutic strategies targeting the epidermal growth factor receptor signaling pathway in metastatic colorectal cancer

More than 1.9 million new colorectal cancer(CRC)cases and 935000 deaths were estimated to occur worldwide in 2020,representing about one in ten cancer cases and deaths.Overall,colorectal ranks third in incidence,but second in mortality.More than half of the patients are in advanced stages at diagnosis.Treatment options are complex because of the heterogeneity of the patient population,including different molecular subtypes.Treatments have included conventional fluorouracil-based chemotherapy,targeted therapy,immunotherapy,etc.In recent years,with the development of genetic testing technology,more and more targeted drugs have been applied to the treatment of CRC,which has further prolonged the survival of metastatic CRC patients.

Advances in targeted therapy for human epidermal growth factor receptor 2 positive in advanced gastric cancer

Emerging therapeutic methods represented by targeted therapy are effective supplements to traditional first-line chemoradiotherapy resistance.Human epidermal growth factor receptor 2(HER2)is one of the most important targets in targeted therapy for gastric cancer.Trastuzumab combined with chemotherapy has been used as the first-line treatment for advanced gastric cancer.The safety and efficacy of pertuzumab and margetuximab in the treatment of gastric cancer have been verified.However,monoclonal antibodies,due to their large molecular weight,inability to penetrate the blood-brain barrier,and drug resistance,lead to decreased therapeutic efficacy,so it is necessary to explore the efficacy of other HER2-targeting therapies in gastric cancer.Small-molecule tyrosine kinase inhibitors,such as lapatinib and pyrrotinib,have the advantages of small molecular weight,penetrating the blood-brain barrier and high oral bioavailability,and are expected to become the drugs of choice for perioperative treatment and neoadjuvant therapy of gastric cancer after validation by large-scale clinical trials in the future.Antibo-drug conjugate,such as T-DM1 and T-DXd,can overcome the resistance of monoclonal antibodies despite their different mechanisms of tumor killing,and are a supplement for the treatment of patients who have failed the treatment of monoclonal antibodies such as trastuzumab.Therefore,after more detailed stratification of gastric cancer patients,various gastric cancer drugs targeting HER2 are expected to play a more significant role.