Human umbilical cord mesenchymal stromal cell small extracellular vesicle transfer of microRNA-223-3p to lung epithelial cells attenuates inflammation in acute lung injury in mice.

BACKGROUND: Acute lung injury (ALI), manifested as strong pulmonary inflammation and alveolar epithelial damage, is a life-threatening disease with high morbidity and mortality. Small extracellular vesicles (sEVs), secreted by multiple types of cells, are critical cellular communication mediators and can inhibit inflammation by transferring bioactive molecules, such as microRNAs (miRNAs). Thus, we hypothesized that sEVs derived from mesenchymal stromal cells (MSC sEVs) could transfer miRNAs to attenuate inflammation of lung epithelial cells during ALI. METHODS: C57BL/6 male mice were intratracheally administered LPS (10 mg/kg). Six hours later, the mice were randomly administered with MSC sEVs (40 µg per mouse in 150 µl of saline), which were collected by ultracentrifugation. Control group received saline administration. After 48 h, the mice were sacrificed to evaluate pulmonary microvascular permeability and inflammatory responses. In vitro, A549 cells and primary human small airway epithelial cells (SAECs) were stimulated with LPS with or without MSC sEVs treatment. RESULTS: In vitro, MSC sEVs could also inhibit the inflammation induced by LPS in A549 cells and SAECs (reducing TNF-α, IL-1ß, IL-6 and MCP-1). Moreover, MSC sEV treatment improved the survival rate, alleviated pulmonary microvascular permeability, and inhibited proinflammatory responses (reducing TNF-α, IL-1ß, IL-6 and JE-1) in ALI mice. Notably, miR-223-3p was found to be served as a critical mediator in MSC sEV-induced regulatory effects through inhibition of poly (adenosine diphosphate-ribose) polymerase-1 (PARP-1) in lung epithelial cells. CONCLUSIONS: Overall, these findings suggest that MSC sEVs may offer a novel promising strategy for ALI.

[Corrigendum] CXCR1 promotes malignant behavior of gastric cancer cells in vitro and in vivo in AKT and ERK1/2 phosphorylation.

Subsequently to the publication of the above article, the authors contacted the Editorial Office to explain that they had inadvertently included data from the same original source in the first row of data panels in Fig. 4B on p. 2191 (showing the results of cell migration assay experiments) to represent two differently performed experiments. Specifically, these images (second and third data panels) containing partially overlapping data corresponded to the 'Vacant­BGC823' in the empty plasmid transfection group and the background 'BGC823 cell' groups, respectively. However, the authors had retained their original data, which they presented to the office for our inspection, and were able to reassemble the data correctly in the figure. The revised version of Fig. 4, showing the replacement data for the 'Vacant­BGC823' and 'BGC823' Migration panels in Fig. 4B, is shown on the next page. The authors are grateful to the Editor of International Journal of Oncology for allowing them this opportunity to publish a Corrigendum, and all the authors agree with its publication. Furthermore, the authors apologize to the readership for any inconvenience caused. [International Journal of Oncology 48: 2184­2196, 2016; DOI: 10.3892/ijo.2016.3428].

Bone mesenchymal stromal cell-derived small extracellular vesicles inhibit inflammation and ameliorate sepsis via delivery of microRNA-21a-5p.

BACKGROUND AIMS: Sepsis is a potentially life-threatening disease that results from a severe systemic inflammatory response due to infection. Mesenchymal stromal cell-derived small extracellular vesicles (MSC sEVs) are able to transfer bioactive molecules and have been demonstrated to play an important role in the pathophysiological process of sepsis. Herein the authors aimed to investigate the potential role and downstream molecular mechanism of MSC sEVs in sepsis. METHODS: MSC sEVs were acquired by ultracentrifugation and then injected into a cecal ligation and puncture mouse model. The efficacy of MSC sEVs in both in vitro and in vivo models of sepsis was evaluated. RESULTS: MSC sEV therapy improved survival, reduced sepsis-induced inflammation, attenuated pulmonary capillary permeability and improved liver and kidney function in septic mice. In addition, the authors found that microRNA-21a-5p (miR-21a-5p) was highly enriched in MSC sEVs, could be transferred to recipient cells, inhibited inflammation and increased survival in septic mice. Furthermore, the authors demonstrated that MSC sEV miR-21a-5p suppressed inflammation by targeting toll-like receptor 4 and programmed cell death 4. The therapeutic efficacy of MSC sEVs was partially abrogated by transfection with miR-21a-5p inhibitors. CONCLUSIONS: Collectively, the authors' data suggest that miR-21a-5p-bearing MSC sEVs may be a prospective and effective sepsis therapeutic strategy.

CAFs-derived small extracellular vesicles circN4BP2L2 promotes proliferation and metastasis of colorectal cancer via miR-664b-3p/HMGB3 pathway.

Our previous research has demonstrated that colorectal cancer (CRC) progression was promoted by circN4BP2L2. This study aimed to further explore the mechanism of circN4BP2L2 in the development of CRC from the perspective of small extracellular vesicles (sEVs). Cancer-associated fibroblasts cell (CAFs) and normal fibroblasts cell (NFs) were isolated from CRC tissues and adjacent tissues, respectively. The ultra-centrifugation was used for extraction of their related sEVs. Cell proliferation and apoptosis were analyzed using CCK-8 and flow cytometry, respectively. Transwell assay was conducted to measure cell migration. The tube formation ability was assessed by tube formation assay. The target relationships between circN4BP2L2 and miR-664b-3p, and miR-664b-3p and HMGB3 were validated by dual-luciferase reporter detection. The effect of CAFs-derived sEV (CAFs-sEVs) circN4BP2L2 on CRC was further studied in nude mice. CAFs-exo promoted cell proliferation, migration, tube formation ability, and inhibited apoptosis of CRC cells. CAFs-sEV circN4BP2L2 knockdown reversed the above results. CircN4BP2L2 directly targeted miR-664b-3p, and HMGB3 was targeted by miR-664b-3p. Moreover, subcutaneous tumorigenesis and liver metastasis of nude mice with CRC were repressed by CAFs-sEV circN4BP2L2 knockdown. CAFs-sEV circN4BP2L2 knockdown restrained CRC cell proliferation and migration by regulating miR-664b-3p/HMGB3 pathway.

CAFs-secreted exosomal cricN4BP2L2 promoted colorectal cancer stemness and chemoresistance by interacting with EIF4A3.

Cancer-associated fibroblasts secreted exosomes (CAFs-exo) are important for tumor carcinogenesis and chemoresistance, but its underlying mechanism in colorectal cancer (CRC) has not yet been clarified. In this study, we investigated the regulatory mechanism of CAFs-exo cricN4BP2L2 on the proliferation, apoptosis, stemness and chemoresistance of LoVo cells. We found that CAFs-exo promoted the oxaliplatin resistance and stemness of LoVo cells, while inhibited the LoVo cell apoptosis. Moreover, knockdown of cricN4BP2L2 in CAFs-exo inhibited the oxaliplatin resistance and stemness characteristics of LoVo cells. Mechanistically, cricN4BP2L2 regulated PI3K/AKT/mTOR axis by binding to EIF4A3. Rescue experiments proved that CAFs-derived exosomal cricN4BP2L2 promoted CRC cells stemness and oxaliplatin resistance by upregulating EIF4A3. Moreover, in vivo experiments showed that depletion of cricN4BP2L2 suppressed CRC tumorigenesis growth. In conclusion, CAFs-exo cricN4BP2L2 promoted the CRC cells stemness and oxaliplatin resistance through EIF4A3/PI3K/AKT/mTOR pathway.

CAF-derived midkine promotes EMT and cisplatin resistance by upregulating lncRNA ST7-AS1 in gastric cancer.

This study aimed to investigate the role of cancer-associated fibroblast (CAF)-derived midkine (MK) in cisplatin (DDP) resistance. The primary cultures of CAFs and non-cancer fibroblasts (NFs) were isolated and purified. The DDP-resistant gastric cancer (GC) cells were cultured with CAF-conditioned medium. QRT-PCR and Elisa assays were employed to determine MK expression. The expression of ST7-AS1 was measured by qRT-PCR. The impact of CAFs, MK, and ST7-AS1 silencing on DDP resistance was determined by MTT and Annexin V/PI staining assay. Expression of EMT markers and PI3K/AKT was determined by Western blot and qRT-PCR. The role of MK in DDP resistance was confirmed in a xenograft model. Incubation with CAF-conditioned medium increased the IC50 to DDP. Also, incubation with CAF-conditioned medium increased cell viability, reduced cell apoptosis, and promoted EMT in DDP-resistant GC cells, which were all blocked with MK neutralization antibody treatment. MK increased the DDP resistance and upregulated the expression of ST7-AS1 in DDP-resistant GC cells. Additionally, ST7-AS1 knockdown increased the sensitivity to DDP by inhibiting EMT. Moreover, ST7-AS1 knockdown significantly decreased the phosphorylation of PI3K and AKT, and suppressed EMT, which were restored by MK addition. Finally, MK promoted tumor growth and DDP resistance in a mice model bearing the SGC-7901/DDP xenografts. CAF-derived MK promotes EMT-mediated DDP resistance via upregulation of ST7-AS1 and activation of PI3K/AKT pathway.

LncRNA HCG18 upregulates TRAF4/TRAF5 to facilitate proliferation, migration and EMT of epithelial ovarian cancer by targeting miR-29a/b.

BACKGROUND: Although long noncoding RNA HLA complex group 18 (lncRNA HCG18) has been suggested to regulate cell growth in several tumours, the function of HCG18 in epithelial ovarian cancer (EOC) and its mechanism are still unclear. METHODS: shRNAs were applied to reduce HCG18 and related genes. For overexpression of miRNA, a miRNA mimic was transfected into cells. Quantitative real-time PCR (qRT-PCR) was used to detect levels of HCG18, miR-29a/b, and mRNAs. MTT, colony formation, wound healing and Transwell assays were used to evaluate cell proliferation, migration and invasion, respectively. A luciferase reporter assay was utilized to evaluate NF-κB activity and the binding of miRNAs with HCG18 or TRAF4/5. BALB nude mice injected with cells stably expressing shHCG18 or shNC were used for in vivo modelling. Subcutaneous tumour growth was monitored in nude mice, and immunohistochemistry (IHC) was used to determine expression of the proliferation marker Ki67. RESULTS: Abnormal expression of HCG18 and miR-29a/b was observed in EOC tissues. Knockdown of HCG18 using shRNA inhibited proliferation, migration, EMT and the proinflammatory pathway in EOC cells. miR-29a/b mimics and TRAF4/5 knockdown exhibited effects similar to HCG18 knockdown. Further experiments suggested that HCG18 directly targets miR-29a/b and upregulates TRAF4/5 expression, which are inhibited by targeting miR-29a/b. Moreover, overexpression of TRAF4/5 antagonized the inhibitory effect of HCG18 knockdown, suggesting that they are involved in HCG18-mediated oncogenic effects. Silencing HCG18 reduced tumour size and levels of Ki67 and TRAF4/5 while increasing miR-29a/b levels in vivo. CONCLUSIONS: Taken together, our data revealed an oncogenic signalling pathway mediated by HCG18 in ovarian cell lines, which functions as a ceRNA of miR-29a/b and thus derepresses expression levels of TRAF4/5, facilitating NF-κB pathway-mediated promotion of EOC cell proliferation and migration.

Primary desmoplastic small round cell tumor of the submandibular gland: a case report and literature review.

BACKGROUND: Desmoplastic small round cell tumor (DSRCT) is a sporadic, highly malignant tumor with a poor prognosis. The abdomen and pelvis have been reported as the primary localization sites. However, to the best of our knowledge, there are few reports on primary DSRCT in the submandibular gland. CASE PRESENTATION: We report a case of a 26-year-old Chinese man with a mass in the right submandibular gland. Imaging studies showed a hypoechoic mass in the right submandibular region. Intraoperative pathology revealed that the tumor tissue was composed of small round tumor cells and a dense desmoplastic stroma. On immunostaining, the tumor cells showed markers of epithelial, mesenchymal, myogenic, and neural differentiation. The EWSR1 gene rearrangement was detected by fluorescence in situ hybridization. Based on the overall morphological features and immunohistochemical findings, a final diagnosis of DSRCT was made. The patient was treated with comprehensive anti-tumor therapy mainly based on radiotherapy and chemotherapy. CONCLUSIONS: DSRCT is an uncommon malignant neoplasm with rare submandibular gland involvement. In this report, we have described a case of DSRCT in the submandibular gland and reviewed the literature on DSRCT over the past 5 years. Considering the importance of differential diagnosis between DSRCT, especially with rare extra-peritoneal involvement, and small round blue cell tumors, a full recognition of the clinicopathological features will help to better diagnose this neoplasm.

CircN4BP2L2 promotes colorectal cancer growth and metastasis through regulation of the miR-340-5p/CXCR4 axis.

Colorectal cancer (CRC) is the third leading cause of cancer-related death worldwide. Dysregulation of circular RNAs (circRNAs) appears to be a critical factor in CRC progression. However, mechanistic studies delineating the role of circRNAs in CRC remain limited. In this study, qRT-PCR and western blot assays were used to measure the expression of genes and proteins. Migration, invasion, proliferation, and apoptosis were examined by wound-healing, transwell, CCK-8, colony formation, and flow cytometry assays, respectively. Molecular interactions were validated by a dual-luciferase report system. A xenograft animal model was established to examine in vivo tumor growth and lung metastasis. Our data indicated that circN4BP2L2 expression was increased in CRC tissues and cell lines. Notably, inhibition of circN4BP2L2 effectively inhibited proliferation, migration, and invasion of LoVo cells, and inhibited tumor growth and metastasis in vivo, whereas the forced expression of circN4BP2L2 facilitated the proliferation, migration, and invasion of HT-29 cells. Mechanistic studies revealed that circN4BP2L2 acted as a molecular sponge of miR-340-5p to competitively promote CXCR4 expression. Furthermore, inhibition of miR-340-5p reversed the anti-cancer effects of circN4BP2L2 or CXCR4 silencing. Our data indicated an oncogenic role of circN4BP2L2 in CRC via regulation of the miR-340-5p/CXCR4 axis, which may be a promising biomarker and target for CRC treatment.

CXCR1 promotes malignant behavior of gastric cancer cells in vitro and in vivo in AKT and ERK1/2 phosphorylation.

CXCR1 is a member of the chemokine receptor family, which was reported to play an important role in several cancers. The present study investigated the influence of CXCR1 stable knockdown or overexpression on the malignant behavior of gastric cancer cells in vitro and in vivo and the potential mechanisms. MKN45 and BGC823 cells were stably transfected with plasmid pYr-1.1-CXCR1-shRNA (knockdown) and pIRES2-ZsGreen1-CXCR1 (overexpression), respectively. Malignant behavior was evaluated in vitro for changes in proliferation by MTT and colony forming assays; cell cycle and apoptosis by flow cytometry; and migration and invasion using transwell and wound-healing assays. Proliferation, cell cycle, apoptosis, migration and invasion-related signaling molecule expression were measured by real-time RT-PCR and western blot analysis. CXCR1 knockdown and overexpressing xenografts were monitored for in vivo tumor growth. Stable knockdown of CXCR1 inhibited MKN45 cell proliferation, migration and invasion, but were reversed in BGC823 cells stably overexpressing CXCR1. In addition, MKN45 cells stably transfected with CXCR1 shRNA inhibited AKT and ERK1/2 phosphorylation, protein expression of cyclin D1, EGFR, VEGF, MMP-9, MMP-2 and Bcl-2, and increased protein expression of Bax and E-cadherin (all P<0.05). In vivo CXCR1-shRNA-MKN45 cells transplanted into nude mice formed smaller tumors than non-transfected or scrambled-shRNA cells (both P<0.05). In contrast BGC823 cells overexpressing CXCR1 formed larger tumors in mice than cells carrying an empty expression plasmid or non-transfected cells (both P<0.05). CXCR1 promoted gastric cancer cell proliferation, migration and invasion. The present study provides preclinical data to support CXCR1 as a novel therapeutic target for gastric cancer.

Repertaxin, an inhibitor of the chemokine receptors CXCR1 and CXCR2, inhibits malignant behavior of human gastric cancer MKN45 cells in vitro and in vivo and enhances efficacy of 5-fluorouracil.

Chemokine-mediated activation of G protein-coupled receptors CXCR1/2 promotes tumor growth, invasion, inflammation and metastasis. Repertaxin, a CXCR1/2 small-molecule inhibitor, has been shown to attenuate many of these tumor-associated processes. The present study aimed to investigate the effects of repertaxin alone and in combination with 5-fluorouracil (5-FU) on the malignant behavior of gastric cancer and the potential mechanisms. Gastric cancer MKN45 cells were treated in vitro with repertaxin and 5-FU, either alone or in combination. MTT and colony formation assay were performed to assess proliferation. Cell cycle progression and apoptosis was completed by flow cytometry. Migration and invasion were also assessed by transwell and wound-healing assay. Western blot analysis and quantitative RT-PCR were performed to determine expression of signaling molecules. MKN45 cells were also grown as xenografts in nude mice. Mice were treated with repertaxin and 5-FU, and tumor volume and weight, angiogenesis, proliferation and apoptosis were monitored. Combination of repertaxin and 5-FU inhibited MKN45 cell proliferation and increased apoptosis better than either agent alone. Similarly, enhanced effect of the combination was also observed in migration and invasion assays. The improved effect of repertaxin and 5-FU was also observed in vivo, as xenograft models treated with both compounds exhibited significantly decreased tumor volume and increased apoptosis. In conclusion, repertaxin inhibited malignant behavior of human gastric cancer MKN45 cells in vitro and in vivo and enhances efficacy of 5-fluorouracil. These data provide rationale that targeting CXCR1/2 with small molecule inhibitors may enhance chemotherapeutic efficacy for the treatment of gastric cancer.

The complete mitochondrial genome of the flesh fly, Boettcherisca peregrine (Diptera: Sarcophagidae).

The complete mitochondrial genome of Boettcherisca peregrine (B. peregrina), an important forensic entomology, was sequenced for the first time. The 14,922 bp circular genome contains 37 genes that were found in a typical Metazoan genome: 13 protein-coding genes, 22 transfer RNA genes and 2 ribosomal RNA genes. It also contains one non-coding A + T-rich region. The arrangement of the genes was the same as that found in the other insect. The overall base composition on heavy strand was as follows: A, 38.86%; G, 15.10%; C, 9.93%; T, 36.11%; and the A + T content 74.97%. The mitochondrial genome of Sarcophaga presented could be valuable for resolving phylogenetic relationships within the order Diptera and especially for the family Sarcophagidae. The molecular data presented may also be used to screen favorable molecular markers for species identifications for forensic entomology purposes.

The complete mitochondrial genome of the scuttle fly, Megaselia scalaris (Diptera: Phoridae).

More than 1400 scuttle flies species in worldwide comprise the Megaselia genus, the largest genus in the family Phoridae. The complete mitochondrial genome of Megaselia scalaris, a medically important entomology was sequenced for the first time. The 15,599 bp circular genome contains the 37 genes found in a typical Metazoan genome: 13 protein-coding genes, 22 transfer RNA genes and 2 ribosomal RNA genes. The mitochondrial genome also contains one non-coding A + T-rich region. The arrangement of the genes was identical with other insect. Each of the base composition on heavy strand was as follows A: 38.87%, G: 13.74%, C: 9.46%, T: 37.93% and the A + T content 76.80%. The mitochondrial genome of M. scalaris presented may be valuable for determining phylogenetic relationships within the order Diptera and especially for the family Phoridae. These sequences could also be used to select reliable molecular markers for species identification in forensic entomology.

MicroRNA-153 functions as a tumor suppressor by targeting SET7 and ZEB2 in ovarian cancer cells.

The overall goal of the present study was to find and validate unidentified miRNAs that regulate epithelial-mesenchymal transition (EMT) and proliferation in ovarian cancer. Furthermore, we demonstrate that the high expression of miR-153 in human epithelial ovarian cancer (EOC) is associated with better survival. The mean expression level of miR-153 in ovarian cancer was significantly lower than in the adjacent carcinoma tissue. In the present study, we report that miR-153 are negative regulators of SET7 and ZEB2, miR-153 regulates SET7/ZEB2 expression and promotes SET7/ZEB2 mRNA degradation. Further, confirmed by reporter assays, SET7/ZEB2 are downstream targets of miR-153 directly bound to the 3' untranslated region (3'-UTR). Clone formation and wound-healing assay as well as Transwell assay proved that silencing of SET7 or ZEB2 partially abolished the enhancement of cell proliferation and invasion induced by downregulated miR-153. SET7 and ZEB2 are negatively correlated with miR-153 expression in human ovarian cancer and indicated a worse survival. Considering the role of SET7 and ZEB2 in EOC, it is important to clarify how the expression of SET7 and ZEB2 are regulated. Based on our results miR-153 inhibits proliferation and suppresses EMT and the invasive potential of ovarian cancer cells through downregulation of SET7 and ZEB2, supporting the pursuit of miR-153 as a potential target for ovarian cancer intervention.

Increases urinary HMGA1 in serous epithelial ovarian cancer patients.

BACKGROUND: Serous epithelial ovarian cancer is the most common variety of ovarian cancer and is currently diagnosed using serum CA-125 levels. HMGA1 a small 10.6-12 kDa protein, has been implicated as a potentially important tumor biomarker and may enter the urinary trace, thus potentially able to serve as a disease biomarker. OBJECTIVE: To determine if urine HMGA1 can be detected and potentially serve as a clinical diagnostic biomarkers. METHOD: Urine was collected from 20 healthy normal control patients, 20 patients with benign gynecological disease and 55 epithelial ovarian specimens of which 20 exhibited G1/2 ovarian cancer and 35 G3 ovarian cancers. Serum was also collected from 20 healthy normal control patients and 55 serous epithelial ovarian cancers patients. HMGA1 levels were examined via enzyme-linked immunosorbent assay (ELISA) and were reported independently and normalized to urine creatinine levels. Serum CA-125 levels were examined via enzyme assay and the data was analyzed via box and ROC analysis. RESULTS: Urine HMGA1 was significantly elevated in serous epithelial ovarian cancer specimen relative to healthy control specimens with G3 specimens exhibiting higher levels than G1-G2 specimens. ROC analysis revealed a high degree of sensitivity and specificity for urine HMGA1 detection in ovarian cancer, with a higher AUC value noted for urine HMGA1 than serum CA-125. Furthermore, urine HMGA1 and serum CA-125 combined AUC indicated that urine HMGA1 is an excellent diagnostic biomarker for serous epithelial ovarian cancer. CONCLUSION: Our data indicates that measuring urine HMGA1 may serve as a useful diagnostic tool.

Epidermal growth factor-like domain-containing protein 7 (EGFL7) enhances EGF receptor-AKT signaling, epithelial-mesenchymal transition, and metastasis of gastric cancer cells.

Epidermal growth factor-like domain-containing protein 7 (EGFL7) is upregulated in human epithelial tumors and so is a potential biomarker for malignancy. Indeed, previous studies have shown that high EGFL7 expression promotes infiltration and metastasis of gastric carcinoma. The epithelial-mesenchymal transition (EMT) initiates the metastatic cascade and endows cancer cells with invasive and migratory capacity; however, it is not known if EGFL7 promotes metastasis by triggering EMT. We found that EGFL7 was overexpressed in multiple human gastric cancer (GC) cell lines and that overexpression promoted cell invasion and migration as revealed by scratch wound and transwell migration assays. Conversely, shRNA-mediated EGFL7 knockdown reduced invasion and migration. Furthermore, EGFL7-overexpressing cells grew into larger tumors and were more likely to metastasize to the liver compared to underexpressing CG cells following subcutaneous injection in mice. EGFL7 overexpression protected GC cell lines against anoikis, providing a plausible mechanism for this enhanced metastatic capacity. In excised human gastric tumors, expression of EGFL7 was positively correlated with expression levels of the mesenchymal marker vimentin and the EMT-associated transcription repressor Snail, and negatively correlated with expression of the epithelial cell marker E-cadherin. In GC cell lines, EGFL7 knockdown reversed morphological signs of EMT and decreased both vimentin and Snail expression. In addition, EGFL7 overexpression promoted EGF receptor (EGFR) and protein kinase B (AKT) phospho-activation, effects markedly suppressed by the EGFR tyrosine kinase inhibitor AG1478. Moreover, AG1478 also reduced the elevated invasive and migratory capacity of GC cell lines overexpressing EGFL7. Collectively, these results strongly suggest that EGFL7 promotes metastasis by activating EMT through an EGFR-AKT-Snail signaling pathway. Disruption of EGFL7-EGFR-AKT-Snail signaling may a promising therapeutic strategy for gastric cancer.

Proteomics-based analysis of differentially expressed proteins in the CXCR1-knockdown gastric carcinoma MKN45 cell line and its parental cell.

C-X-C chemokine receptor types 1 (CXCR1), a cell-surface G-protein-coupled receptor has been found to be associated with tumorigenesis, development, and progression of some tumors. Previously, we have found that CXCR1 overexpression is associated with late-stage gastric adenocarcinoma. We also have demonstrated that knockdown of CXCR1 could inhibit cell proliferation in vitro and in vivo. In this study, we compared the changes of protein expression profile between gastric carcinoma MKN45 cell line and CXCR1-knockdown MKN45 cell line by 2D electrophoresis. Among the 101 quantified proteins, 29 spots were significantly different, among which 13 were down-regulated and 16 were up-regulated after CXCR1 knockdown. These proteins were further identified by mass spectrometry analysis. Among them, several up-regulated proteins such as hCG2020155, Keratin8, heterogeneous nuclear ribonucleoprotein C (C1/C2), and several down-regulated proteins such as Sorcin, heat shock protein 27, serpin B6 isoform b, and heterogeneous nuclear ribonucleoprotein K were confirmed. These proteins are related to cell cycle, the transcription regulation, cell adherence, cellular metabolism, drug resistance, and so on. These results provide an additional support to the hypothesis that CXCR1 might play an important role in proliferation, invasion, metastasis, and prognosis, and drug resistance of gastric carcinoma.