Pseudomonas aeruginosa mannose-sensitive hemagglutinin promotes T-cell response via toll-like receptor 4-mediated dendritic cells to slow tumor progression in mice

Research progress and future directions of immune checkpoint inhibitor combination therapy in advanced gastric cancer

In recent years, with the continuous development of molecular immunology, immune checkpoint inhibitors (ICIs) have also been widely used in the treatment of gastric cancer, but they still face some challenges: The first is that only some people can benefit, the second is the treatment-related adverse events (TRAEs) that occur during treatment, and the third is the emergence of varying degrees of drug resistance with long-term use. How to overcome these challenges, combined therapy based on ICIs has become one of the important strategies. This article summarizes the clinical application of ICIs combined with chemotherapy, targeted therapy, radiotherapy, photodynamic therapy, thermotherapy, immune adjuvant, and dual immunotherapy and discusses the mechanism, and also summarizes the advantages and disadvantages of the current combination modalities and the potential research value. The aim of this study is to provide more and more optimized combination regimen for ICI combined therapy in patients with advanced gastric cancer and to provide reference for clinical and scientific research.

Trends in Anti-Tumor Effects of Pseudomonas aeruginosa Mannose-Sensitive-Hemagglutinin (PA-MSHA): An Overview of Positive and Negative Effects

Cancer is a leading cause of death worldwide, for which finding the optimal therapy remains an ongoing challenge. Drug resistance, toxic side effects, and a lack of specificity pose significant difficulties in traditional cancer treatments, leading to suboptimal clinical outcomes and high mortality rates among cancer patients. The need for alternative therapies is crucial, especially for those resistant to conventional methods like chemotherapy and radiotherapy or for patients where surgery is not possible. Over the past decade, a novel approach known as bacteria-mediated cancer therapy has emerged, offering potential solutions to the limitations of conventional treatments. An increasing number of in vitro and in vivo studies suggest that the subtype of highly virulent Pseudomonas aeruginosa bacterium called Pseudomonas aeruginosa mannose-sensitive-hemagglutinin (PA-MSHA) can successfully inhibit the progression of various cancer types, such as breast, lung, and bladder cancer, as well as hepatocellular carcinoma. PA-MSHA inhibits the growth and proliferation of tumor cells and induces their apoptosis. Proposed mechanisms of action include cell-cycle arrest and activation of pro-apoptotic pathways regulated by caspase-9 and caspase-3. Moreover, clinical studies have shown that PA-MSHA improved the effectiveness of chemotherapy and promoted the activation of the immune response in cancer patients without causing severe side effects. Reported adverse reactions were fever, skin irritation, and pain, attributed to the overactivation of the immune response. This review aims to summarize the current knowledge obtained from in vitro, in vivo, and clinical studies available at PubMed, Google Scholar, and ClinicalTrials.gov regarding the use of PA-MSHA in cancer treatment in order to further elucidate its pharmacological and toxicological properties.

Therapeutic potential of Pseudomonas aeruginosa-mannose sensitive hemagglutinin (PA-MSHA) in cancer treatment

Pseudomonas aeruginosa is a Gram-negative bacteria and it has been demonstrated that immunization with the outer membrane proteins of the microbe produces most of the relevant human antibodies. The peritrichous P. aeruginosa strain with MSHA fimbriae (PA-MSHA strain) has been found to be effective in the inhibition of growth and proliferation of different types of cancer cells. Furthermore, it has been revealed that PA-MSHA exhibits cytotoxicity because of the presence of MSHA and therefore it possesses anti-carcinogenic ability against different types of human cancer cell lines including, gastric, breast, hepatocarcinoma and nasopharyngeal cells. Studies have revealed that PA-MSHA exhibits therapeutic potential against cancer growth by induction of apoptosis, arrest of cell cycle, activating NF-κB/TLR5 pathway, etc. In China, PA-MSHA injections have been approved for the treatment of malignant tumor patients from very long back. The present review article demonstrates the therapeutic potential of PA-MSHA against various types of human cancers and explains the underlying mechanism.

Salidroside regulates tumor microenvironment of non-small cell lung cancer via Hsp70/Stub1/Foxp3 pathway in Tregs

BACKGROUND

The treatment of non-small cell lung cancer (NSCLC) is challenging due to immune tolerance and evasion. Salidroside (SAL) is an extract in traditional Chinese medicine and has a potential antitumor effect. However, the mechanism of SAL in regulating the immunological microenvironment of NSCLC is yet to be clarified.

METHODS

The mouse model with Lewis lung cancer cell line (3LL) in C57BL/6 mice was established. And then, the percentage of tumor-infiltrating T cell subsets including Treg was detected in tumor-bearing mice with or without SAL treatment. In vitro, the effect of SAL on the expression of IL-10, Foxp3 and Stub1 and the function of Treg were detected by flow cytometry. Network pharmacology prediction and molecular docking software were used to predict the target of SAL and intermolecular interaction. Furthermore, the effect of SAL on the expression of Hsp70 and the co-localization of Stub1-Foxp3 in Treg was confirmed by flow cytometry and confocal laser microscopy. Finally, Hsp70 inhibitor was used to verify the above molecular expression.

RESULTS

We discovered that SAL treatment inhibits the growth of tumor cells by decreasing the percentage of tumor-infiltrated CD4⁺Foxp3⁺T cells. SAL treatment downregulates the expression of Foxp3 in Tregs, but increases the expression of Stub1, an E3 ubiquitination ligase upstream of Foxp3, and the expression of Hsp70. Inhibiting the expression of Hsp70 reverses the inhibition of SAL on Foxp3 and disrupts the colocalization of Stub1 and Foxp3 in the nucleus of Tregs.

CONCLUSIONS

SAL inhibits tumor growth by regulating the Hsp70/stub1/Foxp3 pathway in Treg to suppress the function of Treg. It is a new mechanism of SAL for antitumor therapy.

PA-MSHA Regulates PD-L1 Expression in Hepatoma Cells

BACKGROUND

Programmed death ligand 1 (PD-L1) is expressed in hepatocellular carcinoma (HCC) cells. PD-L1 function and structure are regulated through glycosylation and various signaling pathways. However, the relationship between Pseudomonas aeruginosa mannose sensitive hemagglutinin (PA-MSHA), glycosylation and PD-L1 warrants further study. In this study, we investigated the effects of PA-MSHA on the regulation of mannosyl and N-glycosylation to identify the mechanisms underlying its function.

METHODS

PD-L1, β-catenin, c-Myc, mannosyl, MGAT1 and mannosidase II in HCC were identified by postoperative specimens from the HCC cohort with immunohistochemistry and immunofluorescence. PA-MSHA was used to suppress tumor progression. Alterations to the expression of PD-L1, β-catenin, c-Myc, MGAT1, and mannosidase II at the gene and protein levels were detected by qRT-PCR and Western blot analysis. Soluble PD-L1 (sPD-L1) were detected using enzyme-linked immunosorbent assay.

RESULTS

Mannosyl and mannosidase II expression levels increased, whereas those of MGAT1 decreased in the HCC cells. The glycosylation-related pathway proteins, namely, β-catenin, c-Myc and PD-L1, had increased expression levels. Moreover, proliferation in the HCC cells was inhibited after PA-MSHA treatment, PD-L1 function was significantly inhibited. Transmission electron microscopy showed that PA-MSHA penetrated into the HCC cytoplasm through the cytomembrane, resulting in apoptosis. Here, PA-MSHA significantly reduced sPD-L1 expression levels in the tumor cells.

CONCLUSIONS

PA-MSHA plays the role of a lectin, affecting receptors on the cytomembrane. This strain inhibits mannosyl by suppressing β-catenin signaling. We hypothesized that PA-MSHA suppresses PD-L1 by: 1. Inhibiting the glycosylation process; and 2. Suppressing β-catenin and c-Myc, thereby reducing the transcription of this protein.

Pseudomonas aeruginosa in Cancer Therapy: Current Knowledge, Challenges and Future Perspectives

Drug resistance, undesirable toxicity and lack of selectivity are the major challenges of conventional cancer therapies, which cause poor clinical outcomes and high mortality in many cancer patients. Development of alternative cancer therapeutics are highly required for the patients who are resistant to the conventional cancer therapies, including radiotherapy and chemotherapy. The success of a new cancer therapy depends on its high specificity to cancer cells and low toxicity to normal cells. Utilization of bacteria has emerged as a promising strategy for cancer treatment. Attenuated or genetically modified bacteria were used to inhibit tumor growth, modulate host immunity, or deliver anti-tumor agents. The bacteria-derived immunotoxins were capable of destructing tumors with high specificity. These bacteria-based strategies for cancer treatment have shown potent anti-tumor effects both in vivo and in vitro, and some of them have proceeded to clinical trials. Pseudomonas aeruginosa, a Gram-negative bacterial pathogen, is one of the common bacteria used in development of bacteria-based cancer therapy, particularly known for the Pseudomonas exotoxin A-based immunotoxins, which have shown remarkable anti-tumor efficacy and specificity. This review concisely summarizes the current knowledge regarding the utilization of P. aeruginosa in cancer treatment, and discusses the challenges and future perspectives of the P. aeruginosa-based therapeutic strategies.

Analysis of factors influencing postoperative drainage time in breast cancer

BACKGROUND

To investigate the related factors affecting the postoperative indwelling time of drainage tubes (hereinafter referred to as drainage time) in breast cancer (BC) and evaluate the effect of Pseudomonas aeruginosa-mannose-sensitive hemagglutinin (PA-MSHA) preparation on reducing postoperative drainage time.

METHODS

The clinical data of 165 BC patients in our hospital, including the postoperative drainage time and occurrence of seroma and related complications (such as fever, incision infection, and flap necrosis) after extubation, were retrospectively analyzed. Univariate, multivariate, and stratified analyses were used to determine the correlations between 15 factors including age, body weight, body mass index (BMI), and PA-MSHA preparation, and the postoperative total drainage volume and drainage time.

RESULTS

Age, BMI, and PA-MSHA preparation were independent factors affecting the postoperative drainage volume and drainage time of BC patients. Age and BMI were positively correlated with postoperative drainage volume and drainage time (P≤0.004, P≤0.037). PA-MSHA preparation significantly reduced the postoperative total drainage volume and drainage time (P<0.001), decreased the incidence of seroma after extubation (P=0.024), and did not increase complications (P>0.05).

CONCLUSIONS

Obese and elderly patients were at a significantly high risk of a high drainage volume and long drainage time. Local treatment with PA-MSHA preparation had the advantages of reducing postoperative drainage volume, reducing drainage time, preventing seroma, and not increasing complications, and was a safe and effective treatment. For BC patients aged over 60 years and with a BMI ≥25, the intraoperative local spraying of wounds with PA-MSHA preparation to reduce postoperative drainage times is a valuable option.

Intravesical Pseudomonas aeruginosa mannose-sensitive Hemagglutinin vaccine triggers a tumor-preventing immune environment in an orthotopic mouse bladder cancer model

Bacillus Calmette-Guerin (BCG) immunotherapy can prevent recurrence and progression in selected patients with non-muscle-invasive bladder cancer (NMIBC); however, significant adverse events and treatment failure suggest the need for alternative agents. A commercial anti-infection vaccine comprises a genetically engineered heat-killed Pseudomonas aeruginosa (PA) expressing many mannose-sensitive hemagglutination (MSHA) fimbriae, termed PA-MSHA, which could be a candidate for bladder cancer intravesical therapy. In an immunocompetent orthotopic MB49 bladder cancer model, we characterized the antitumor effects and mechanisms of PA-MSHA compared with those of BCG. Three weekly intravesical PA-MSHA or BCG treatments reduced tumor involvement; however, only PA-MSHA prolonged survival against MB49 implantation significantly. In non-tumor-bearing mice after treatment, flow-cytometry analysis showed PA-MSHA and BCG induced an increased CD4/CD8 ratio, the levels of effector memory T cell phenotypes (CD44, CXCR-3, and IFN-γ), and the proportion of CD11b⁺Ly6G^-Ly6C^-IA/IE⁺ mature macrophages, but a decrease in the proportion of CD11b⁺Ly6G^-Ly6C⁺IA/IE^- monocytic myeloid-derived suppressor cells (Mo-MDSCs) and the expression of suppressive molecules on immune cells (PD-L1, PD-1, TIM-3, and LAG-3). Notably, PA-MSHA, but not BCG, significantly reduced PD-1 and TIM-3 expression on CD4⁺ T cells, which might account for the better effects of PA-MSHA than BCG. However, in tumor-bearing mice after treatment, the increased proportion of Mo-MDSCs and high expression of PD-L1 might be involved in treatment failure. Thus, modulating the balance among adaptive and innate immune responses was identified as a key process underlying PA-MSHA-mediated treatment efficacy. The results demonstrated mechanisms underlying intravesical PA-MSHA therapy, pointing at its potential as an alternative effective treatment for NMIBC.

Exosomal miR-92b-3p Promotes Chemoresistance of Small Cell Lung Cancer Through the PTEN/AKT Pathway

Resistance to first-line chemotherapy drugs has become an obstacle to improving the clinical prognosis of patients with small cell lung cancer (SCLC). Exosomal microRNAs have been shown to play pro- and anti-chemoresistant roles in various cancers, but their role in SCLC chemoresistance has never been explored. In this study, we observed that the expression of exosomal miR-92b-3p was significantly increased in patients who developed chemoresistance. Luciferase reporter analysis confirmed that PTEN was a target gene of miR-92b-3p. The PTEN/AKT regulatory network was related to miR-92b-3p-mediated cell migration and chemoresistance in vitro and in vivo in SCLC. Importantly, exosomes isolated from the conditioned medium of SBC-3 cells overexpressing miR-92b-3p could promote SCLC chemoresistance and cell migration. Furthermore, we found that plasma miR-92b-3p levels were significantly higher in patients with chemoresistant SCLC than in those with chemosensitive SCLC, but the levels were down-regulated in patients who achieved remission. Kaplan–Meier analysis showed that SCLC patients with high miR-92b-3p expression were associated with shorter progression-free survival. Overall, our results suggested that exosomal miR-92b-3p is a potential dynamic biomarker to monitor chemoresistance in SCLC and represents a promising therapeutic target for chemoresistant SCLC.

P. aeruginosa Mediated Necroptosis in Mouse Tumor Cells Induces Long-Lasting Systemic Antitumor Immunity

Necroptosis is a form of programmed cell death (PCD) characterized by RIP3 mediated MLKL activation and increased membrane permeability via MLKL oligomerization. Tumor cell immunogenic cell death (ICD) has been considered to be essential for the anti-tumor response, which is associated with DC recruitment, activation, and maturation. In this study, we found that P. aeruginosa showed its potential to suppress tumor growth and enable long-lasting anti-tumor immunity in vivo. What's more, phosphorylation- RIP3 and MLKL activation induced by P. aeruginosa infection resulted in tumor cell necrotic cell death and HMGB1 production, indicating that P. aeruginosa can cause immunogenic cell death. The necrotic cell death can further drive a robust anti-tumor response via promoting tumor cell death, inhibiting tumor cell proliferation, and modulating systemic immune responses and local immune microenvironment in tumor. Moreover, dying tumor cells killed by P. aeruginosa can catalyze DC maturation, which enhanced the antigen-presenting ability of DC cells. These findings demonstrate that P. aeruginosa can induce immunogenic cell death and trigger a robust long-lasting anti-tumor response along with reshaping tumor microenvironment.

Pseudomonas aeruginosa injection decreases drainage in lateral neck dissection for metastatic thyroid cancer

Background

Pseudomonas aeruginosa injection (PAI) has been proven effective against chylous fistula but not in decreasing drainage after lateral neck dissection (LND). To verify the safety of spraying PAI onto the surface of the traumatic cavity after total thyroidectomy with LND and to evaluate whether its application can reduce the drainage volume.

Methods

A total of 85 patients with metastatic papillary thyroid cancer (PTC) who agreed to total thyroidectomy with unilateral LND were recruited from March 2016 to September 2017. During the operation, PAI was applied in 44 patients, while 41 remaining patients served as the control group. The thyroid function and parathyroid function, drainage volume, hospital stay, and incidence of complications were compared between the two groups.

Results

The groups had few differences in age, gender, BMI, thyroid function, parathyroid function, diameter of tumor, and the number of the harvested lymph nodes. The median total drainage volume was significantly smaller and the mean hospital stay was obviously shorter in the PAI group compared to the non-PAI group. But the median volumes of peak 24-hour drainage which appeared during the first day after operation had few differences in the two groups. Postoperative fever in the PAI group was higher than in the non-PAI group. None of the patients had permanent recurrent laryngeal nerve paralysis and tumor recurrence on the 12^th month after operation.

Conclusions

The application of PAI to the wound cavity after LND is safe and effective for reducing the drainage volume and hospital stay.

MicroRNA-138-5p Suppresses Non-small Cell Lung Cancer Cells by Targeting PD-L1/PD-1 to Regulate Tumor Microenvironment

Non-small cell lung cancer (NSCLC) is still challenging for treatment owing to immune tolerance and evasion. MicroRNA-138 (miR-138) not only acts as a tumor suppressor to inhibit tumor cell proliferation and migration but also regulates immune response. The regulatory mechanism of miR-138 in NSCLC remains not very clear. Herein, we demonstrated that miR-138-5p treatment decreased the growth of tumor cells and increased the number of tumor-infiltrated DCs. miR-138-5p not only down-regulated the expression of cyclin D3 (CCND3), CCD20, Ki67, and MCM in A549/3LL cells, but also regulated the maturation of DCs in A549-bearing nude mice and the 3LL-bearing C57BL/6 mouse model, and DCs’ capability to enhance T cells to kill tumor cells. Furthermore, miR-138-5p was found to target PD-L1 to down-regulate PD-L1 on tumor cells to reduce the expression of Ki67 and MCM in tumor cells and decrease the tolerance effect on DCs. miR-138-5p also directly down-regulates the expression of PD-L1 and PD-1 on DCs and T cells. Similar results were obtained from isolated human non-small cell lung cancer (NSCLC) cells and DCs. Thus, miR-138-5p inhibits tumor growth and activates the immune system by down-regulating PD-1/PD-L1 and it is a promising therapeutic target for NSCLC.

Pseudomonas aeruginosa-mannose-sensitive hemagglutinin inhibits chemical-induced skin cancer through suppressing hedgehog signaling

Pseudomonas aeruginosa-mannose-sensitive hemagglutinin (PAM) is an inactivate P. aeruginosa with mannose-sensitive hemagglutinin. Recently, the anticancer properties of PAM against many cancers have been reported across a range of studies. However, the exact mechanism through which PAM prevents skin cancer remains unclear. The aim of this study is to show to what extent PAM could inhibit the dimethylbenzanthracene (DMBA)/12-O-tetradecanoylphorbol-13-acetate (TPA)-induced skin cancer. JB6 cells were treated by TPA so as to establish an in vitro model. The effects of PAM on proliferation of the cells were analyzed using cell counting kit-8 assays. Effects on epithelial–mesenchymal transition (EMT) were assayed by real-time PCR and Western blotting. A DMBA/TPA-induced skin cancer mouse model was also established. The results showed that TPA promoted EMT changes through the activation of the hedgehog (Hh) pathway, which was reversed by PAM. Moreover, PAM inhibited the cancer growth and Hh pathway in vivo. These data indicate that PAM may serve as a potential anticancer agent for the treatment of skin cancer.

Impact statement

Pseudomonas aeruginosa-mannose-sensitive hemagglutinin (PAM) restrained the chemical-induced skin cancer cells in vitro and in vivo partly through suppressing the Hh signaling pathway, indicating that PAM may be a promising anticancer agent for treating skin cancer.

Ultrasound-guided percutaneous injection of Pseudomonas aeruginosa-mannose sensitive hemagglutinin for treatment of chyle fistula following neck dissection: Two case reports

RATIONALE

Chyle fistula is a rare but troublesome complication of neck dissection. Topical application of Pseudomonas aeruginosa-mannose sensitive hemagglutinin (PA-MSHA) injection has been reported as a novel, viable, and effective approach in the treatment of chyle fistula following neck dissection. However, there have been no reports regarding the treatment of chyle fistula using ultrasound (US)-guided percutaneous injection of PA-MSHA.

PATIENT CONCERNS

We describe 2 patients with thyroid cancer who developed chyle fistula following neck dissection, which remained unresolved despite the use of conservative treatment.

DIAGNOSES

Both the patients were diagnosed with chyle fistula by laboratory testing, which showed that drainage fluid triglyceride concentration was >100 mg/dL.

INTERVENTIONS

When conservative treatment failed, a 2 mL undiluted PA-MSHA preparation was percutaneously injected at the effusion site of the left supraclavicular area under US guidance with aseptic technique. Concomitantly, the drainage tube was clamped for at least 30 minutes.

OUTCOMES

Chyle fistula in both patients were successfully resolved with this technique within 2 or 4 days, without notable side effects.

LESSONS

US-guided percutaneous injection of PA-MSHA is a simple and effective method to treat chyle fistula following neck dissection, which may serve as a useful addition to the medical treatment for cervical chyle fistula.

Pseudomonas aeruginosa-mannose sensitive hemagglutinin injection therapy for the treatment of chyle fistula following neck dissection

BACKGROUND

The efficacy of Pseudomonas aeruginosa-mannose sensitive hemagglutinin (PA-MSHA) injection therapy in the treatment of chyle fistula following neck dissection is unclear.

METHODS

This prospective study enrolled 26 patients who developed chyle fistula after neck dissection. Patients were divided into high-output (>500 mL) and low-output groups (≤500 mL) and were initially treated conservatively for 5 days in the high-output group or 7 days in the low-output group. When conservative treatment failed, topical PA-MSHA therapy was applied.

RESULTS

Twelve of 26 patients were cured with conservative treatment, and the remaining 14 patients were all successfully resolved by PA-MSHA therapy. Chyle fistula got resolved in the low-output and high-output groups after the initiation of therapy were at a median 1 days and 6 days, respectively. Among them, 12 (85.7%) patients experienced fever and 11 (78.6%) patients experienced neck pain.

CONCLUSIONS

Topical PA-MSHA injection therapy could effectively manage chyle fistula following neck dissection.

Effect of PA-MSAH preprocessing on the expression of TLR-4-NF-κB pathway and inflammatory factors in the intestinal tract of rats with septic shock

Effects of Pseudomona blank s aeruginosa-mannose sensitive hemagglutini (PA-MSHA) preprocessing on toll like receptor (TLR)-4-NF-κB pathway and inflammatory factors expression in the intestinal tract of rats with septic shock were investigated. A total of 30 rats were randomly divided into 3 groups (n=10): Blank control, septic shock, and PA-septic shock group. After the model was successfully established, the average arterial pressure in rats was monitored. The concentration of cytokine interleukin-l (IL-1), IL-6 and tumor necrosis factor-α (TNF-α) were determined by ELISA method. Flow cytometry was performed to detect TLR-4 expression. Number of in vitro chemotaxised neutrophils was detected by Transwell chamber. The expression of TLR-4, NF-κB and ICAM-1 and VCAM-1 was detected by western blot analysis. The concentration of cytokine IL-1, IL-6, TNF-α in the peritoneal lavage fluid and the intestinal tissue significantly increased in the septic shock group and the PA-septic shock group (P<0.05), and the concentration in the PA-septic shock group was significantly lower than that of the septic shock group (P<0.05). Compared to the control group, the expression of TLR-4, NF-κB and ICAM-1 and VCAM-1 increased in the septic shock and PA-septic shock group (P<0.05), and the expression level of PA-septic shock group was lower than the septic shock group (P<0.05). The expression of TLR-4 in the PA-septic shock group was lower than the septic shock group (P<0.05). PA-MSHA pretreatment reduced inflammation, thus preventing the intestinal injury caused by septic shock.

Pseudomonas aeruginosa-mannose sensitive hemagglutinin injection treated cytokine-induced killer cells combined with chemotherapy in the treatment of malignancies

Pseudomonas aeruginosa-mannose sensitive hemagglutinin (PA-MSHA) injection serves as immunological adjuvant in clinical treatment of cancer patients. In present study, we investigated whether PA-MSHA injection enhanced the anti-tumor efficacy of CIK cells. Twenty patients with malignancies were enrolled in this retrospective clinical trial. They were divided into two groups: 10 patients received PA-MSHA treated CIK cells transfusion combined with chemotherapy, and other patients accepted CIK cells and chemotherapy. The efficacy of PA-MSHA treated CIK cells was also observed in vitro and in vivo. With PA-MSHA treatment CIK cells exhibited enhanced proliferation but decreased expression of inhibitory cell surface markers such as Tim-3 and PD-1. Particularly in CIK cells, PA-MSHA promoted the extrusion of pro-inflammatory cytokines like IFN-γ. Of 10 patients with PA-MSHA treated CIK cells and chemotherapy, two patients reached partial remissions, 7 patients had stable disease and the other one had progressive disease. Some of these patients experienced fever after cell infusion. 8 patients with CIK cells showed stable disease and 2 patients had progressive disease. Moreover, the side effects were small in patients with CIK treatment. Our data indicated that PA-MSHA improves the functions of CIK cells and shed new light on developing more potent therapeutic approaches for malignancies.

Pseudomonas aeruginosa injection enhanced antitumor cytotoxicity of cytokine-induced killer cells derived from cord blood

Cord blood (CB) is becoming an extensive source of cytokine-induced killer cells. It had been used in several clinical settings and proven to be efficacious and safe. Therefore, we investigated the possibility of combining CIK cells derived from cord blood (CB-CIK) and Pseudomonas aeruginosa injection (PA-MSHA) in order to enhance the cytotoxicity of CB-CIK cells against tumors. Compared with the CB-CIK cells, the PA-MSHA-treated CB-CIK cells demonstrated with increased proliferation rates, higher expression of activated cell surface marker CD28 and lower expression of inhibited cell surface markers PD-1 and CTLA-4. Furthermore, PA-MSHA-treated CB-CIK cells exhibited more effectively for secreting pro-inflammatory cytokine such as IFN-γ and expressing high levels of TLR2, TLR4 and TLR6. The expression of CD107a was higher in the CD3(+)CD56(+) subset of PA-MSHA-treated CB-CIK cells. Our results indicate that the PA-MSHA-treated CB-CIK cells exhibited a more potent in cytotoxic activity against tumor cells. Thus, PA-MSHA enhanced the antitumor ability of CB-CIK cells.