Expression of granulocyte colony stimulating factor receptor in human colorectal cancer

NLRP3-Induced NETosis: A Potential Therapeutic Target for Ischemic Thrombotic Diseases?

Ischemic thrombotic disease, characterized by the formation of obstructive blood clots within arteries or veins, is a condition associated with life-threatening events, such as stroke, myocardial infarction, deep vein thrombosis, and pulmonary embolism. The conventional therapeutic strategy relies on treatments with anticoagulants that unfortunately pose an inherent risk of bleeding complications. These anticoagulants primarily target clotting factors, often overlooking upstream events, including the release of neutrophil extracellular traps (NETs). Neutrophils are integral components of the innate immune system, traditionally known for their role in combating pathogens through NET formation. Emerging evidence has now revealed that NETs contribute to a prothrombotic milieu by promoting platelet activation, increasing thrombin generation, and providing a scaffold for clot formation. Additionally, NET components enhance clot stability and resistance to fibrinolysis. Clinical and preclinical studies have underscored the mechanistic involvement of NETs in the pathogenesis of thrombotic complications, since the clots obtained from patients and experimental models consistently exhibit the presence of NETs. Given these insights, the inhibition of NETs or NET formation is emerging as a promising therapeutic approach for ischemic thrombotic diseases. Recent investigations also implicate a role for the nucleotide-binding oligomerization domain (NOD)-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome as a mediator of NETosis and thrombosis, suggesting that NLRP3 inhibition may also hold potential for mitigating thrombotic events. Therefore, future preclinical and clinical studies aimed at identifying and validating NLRP3 inhibition as a novel therapeutic intervention for thrombotic disorders are imperative.

Tumor-derived GCSF Alters Tumor and Systemic Immune System Cell Subset Composition and Signaling

While immunotherapies such as immune checkpoint blockade and adoptive T-cell therapy improve survival for a subset of human malignancies, many patients fail to respond. Phagocytes including dendritic cells (DC), monocytes, and macrophages (MF) orchestrate innate and adaptive immune responses against tumors. However, tumor-derived factors may limit immunotherapy effectiveness by altering phagocyte signal transduction, development, and activity. Using Cytometry by Time-of-Flight, we found that tumor-derived GCSF altered myeloid cell distribution both locally and systemically. We distinguished a large number of GCSF-induced immune cell subset and signal transduction pathway perturbations in tumor-bearing mice, including a prominent increase in immature neutrophil/myeloid-derived suppressor cell (Neut/MDSC) subsets and tumor-resident PD-L1⁺ Neut/MDSCs. GCSF expression was also linked to distinct tumor-associated MF populations, decreased conventional DCs, and splenomegaly characterized by increased splenic progenitors with diminished DC differentiation potential. GCSF-dependent dysregulation of DC development was recapitulated in bone marrow cultures in vitro, using medium derived from GCSF-expressing tumor cell cultures. Importantly, tumor-derived GCSF impaired T-cell adoptive cell therapy effectiveness and was associated with increased tumor volume and diminished survival of mice with mammary cancer. Treatment with neutralizing anti-GCSF antibodies reduced colonic and circulatory Neut/MDSCs, normalized colonic immune cell composition and diminished tumor burden in a spontaneous model of mouse colon cancer. Analysis of human colorectal cancer patient gene expression data revealed a significant correlation between survival and low GCSF and Neut/MDSC gene expression. Our data suggest that normalizing GCSF bioactivity may improve immunotherapy in cancers associated with GCSF overexpression.

Significance

Tumor-derived GCSF leads to systemic immune population changes. GCSF blockade restores immune populations, improves immunotherapy, and reduces tumor size, paralleling human colorectal cancer data. GCSF inhibition may synergize with current immunotherapies to treat GCSF-secreting tumors.

Xuanhusuo powder has an anti-breast cancer effect by inhibiting myeloid-derived suppressor cell differentiation in the spleen of mice through down-regulating granulocyte colony stimulating factor

OBJECTIVES

To investigate the mechanism of Xuanhusuo powder (XHSP) inhibiting the differentiation of spleen myeloid-derived suppressor cells (MDSCs) in breast cancer mice.

METHODS

Forty-eight BALB/c female mice aged 4-5 weeks were selected, 6 of them were in normal control group, while others were in tumor-bearing models established by orthotopic injection of 4T1 cells into the subcutaneous fat pad of the second pair of left mammary glands. The tumor-bearing mice were divided into granulocyte colony stimulating factor (G-CSF) control group, G-CSF knock-down group, model control group, XHSP small dose group, XHSP medium dose group, XHSP high dose group, and cyclophosphamide (CTX) group, with 6 mice in each group. G-CSF control group and G-CSF knock-down group were constructed by stably transfecting 4T1 cells established by shRNA lentivirus combined with puromycin selection. 48 h after the model was established, XHSP small, medium, high dose group were given 2, 4, 8 g·kg－1·d－1 intragastric administration once a day, respectively. CTX was given 30 mg/kg by intraperitoneal injection, once every other day. The other groups were given an equal volume of 0.5% hydroxymethylcellulose sodium. The drugs in each group were continuously administered for 25 d. Histological changes in spleen were observed by HE staining, the proportion of MDSCs subsets in the spleen were detected by flow cytometry, the co-expression of CD11b and Ly6G in the spleen was detected by immunofluorescence, and the concentration of G-CSF in peripheral blood was detected by ELISA. The spleen of tumor-bearing mice was co-cultured with 4T1 stably transfected cell lines in vitro, treated with XHSP (30 μg/mL) for 24 h, and the co-expression of CD11b and Ly6G in the spleen was detected by immunofluorescence. 4T1 cells were treated by XHSP (10, 30, 100 μg/mL) for 12 h. The mRNA level of G-CSF was detected by realtime RT-PCR.

RESULTS

Compared with normal mice, the red pulp of the spleen in tumor-bearing mice was widened with megakaryocyte infiltration. The proportion of spleen polymorphonucleocyte-like MDSCs (PMN-MDSCs) was significantly increased (P<0.01) and the co-expression of CD11b and Ly6G was increased, and the concentration of G-CSF in peripheral blood was significantly increased (P<0.01). However, XHSP could significantly reduce the proportion of PMN-MDSCs (P<0.05) and the co-expression of CD11b and Ly6G in the spleen, down-regulate the mRNA level of G-CSF in 4T1 cells (P<0.01). The concentration of G-CSF in peripheral blood of tumor-bearing mice also decreased (P<0.05) and tumor volume was reduced and splenomegaly was improved (all P<0.05).

CONCLUSIONS

XHSP may play an anti-breast cancer role by down-regulating G-CSF, negatively regulating the differentiation of MDSCs, and reconstruct the spleen myeloid microenvironment.

No NETs no TIME: Crosstalk between neutrophil extracellular traps and the tumor immune microenvironment

The tumor immune microenvironment (TIME) controls tumorigenesis. Neutrophils are important components of TIME and control tumor progression and therapy resistance. Neutrophil extracellular traps (NETs) ejected by activated neutrophils are net-like structures composed of decondensed extracellular chromatin filaments decorated with a plethora of granules as well as cytoplasmic proteins. Many of these harbour post translational modifications. Cancer cells reportedly trigger NET formation, and conversely, NETs alter the TIME and promote tumor cell proliferation and migration. The specific interactions between NETs and TIME and the respective effects on tumor progression are still elusive. In certain tumors, a CD4⁺ T helper (Th) 2 cell-associated TIME induces NETs and exerts immunosuppressive functions via programmed death 1 (PD-1)/PD-L1, both associated with poorer prognosis. In other cases, NETs induce the proliferation of Th1 cells, associated with an improved prognosis in cancer. In addition, NETs can drive macrophage polarization and often rely on macrophages to promote cancer cell invasion and metastasis. In turn, macrophages can swiftly clear NETs in an immunologically silent manner. The aim of this review is to summarize the knowledge about the mutual interaction between NETs and TIME and its impact on tumor growth and therapy.

Azithromycin and Ceftriaxone Differentially Activate NLRP3 in LPS Primed Cancer Cells

Background: Cancer patients are prescribed antibiotics, such as macrolides and lactamides, for infection treatment. However, the effect of these antibiotics on NLRP3 activation remains largely unknown. Method: Lung cancer (A549) and prostate cancer (PC3) cell lines were primed with lipopolysaccharide (LPS) to activate NLRP3 transcription. Cells were then treated with azithromycin (Az) or ceftriaxone (Cf). NLRP3 activation was analyzed by qPCR, Western blot, and ELISA. Cell growth and viability were assessed by real-time cell analysis and Annexin V expression. Levels of 41 cytokines were also analyzed using a multiplex assay. Results: LPS-Az activated transcription of NLRP3, Pro-CASP-1, and Pro-IL-1β in A549 cells, while failing to upregulate NLRP3 and Pro-IL-1β in PC3 cells. LPS-Az decreased the secretion of pro-inflammatory cytokines while it induced the pro-angiogenic factors in A549 and PC3 cells. In contrast, LPS-Cf suppressed the expression of NLRP3-associated genes, NLRP3 protein expression, the inflammatory cytokine secretion in A549 and PC3 cells. LPS-Az and LPS-Cf had a limited effect on cell growth and viability. Discussion: Our data suggest that Cf could suppress LPS induced NLRP3, which should be considered when selecting antibiotics for cancer treatment. In contrast, the effect of Az on LPS primed NLRP3 and the inflammatory cytokines production appears to depend on the cancer cell origin. Therefore, these data indicate that considerations are required when selecting Az for the treatment of cancer patients.

Granulocyte colony-stimulating factor promotes an aggressive phenotype of colon and breast cancer cells with biochemical changes investigated by single-cell Raman microspectroscopy and machine learning analysis

Granulocyte colony-stimulating factor (G-CSF) is produced at high levels in several cancers and is directly linked with metastasis in gastrointestinal (GI) cancers. In order to further understand the alteration of molecular compositions and biochemical features triggered by G-CSF treatment at molecular and cell levels, we sought to investigate the long term treatment of G-CSF on colon and breast cancer cells measured by label-free, non-invasive single-cell Raman microspectroscopy. Raman spectrum captures the molecule-specific spectral signatures ("fingerprints") of different biomolecules presented on cells. In this work, mouse breast cancer line 4T1 and mouse colon cancer line CT26 were treated with G-CSF for 7 weeks and subsequently analyzed by machine learning based Raman spectroscopy and gene/cytokine expression. The principal component analysis (PCA) identified the Raman bands that most significantly changed between the control and G-CSF treated cells. Notably, here we proposed the concept of aggressiveness score, which can be derived from the posterior probability of linear discriminant analysis (LDA), for quantitative spectral analysis of tumorigenic cells. The aggressiveness score was effectively applied to analyze and differentiate the overall cell biochemical changes of G-CSF-treated two model cancer cells. All these tumorigenic progressions suggested by Raman analysis were confirmed by pro-tumorigenic cytokine and gene analysis. A high correlation between gene expression data and Raman spectra highlights that the machine learning based non-invasive Raman spectroscopy offers emerging and powerful tools to better understand the regulation mechanism of cytokines in the tumor microenvironment that could lead to the discovery of new targets for cancer therapy.

G-CSF in tumors: Aggressiveness, tumor microenvironment and immune cell regulation

Granulocyte colony-stimulating factor (G-CSF) is a cytokine most well-known for maturation and mobilization of bone marrow neutrophils. Although it is used therapeutically to treat chemotherapy induced neutropenia, it is also highly expressed in some tumors. Case reports suggest that tumors expressing high levels of G-CSF are aggressive, more difficult to treat, and present with poor prognosis and high mortality rates. Research on this topic suggests that G-CSF has tumor-promoting effects on both tumor cells and the tumor microenvironment. G-CSF has a direct effect on tumor cells to promote tumor stem cell longevity and overall tumor cell proliferation and migration. Additionally, it may promote pro-tumorigenic immune cell phenotypes such as M2 macrophages, myeloid-derived suppressor cells, and regulatory T cells. Overall, the literature suggests a plethora of pro-tumorigenic activity that should be balanced with the therapeutic use. In this review, we present an overview of the multiple complex roles of G-CSF and G-CSFR in tumors and their microenvironment and discuss how clinical advances and strategies may open new therapeutic avenues.

Expression of recombinant G-CSF receptor domains and their inhibitory role on G-CSF function

Background and purpose:

Granulocyte colony-stimulating factor (G-CSF) is routinely used in combination with chemotherapy to battle neutropenia. However, studies suggest that this chemokine may increase the risk of metastasis and malignancy in many cancers. To counteract the adverse effects of G-CSF in cancer, antibodies have been used to block its action. However, antibodies are large and complex molecules which makes their production expensive. Thus in this study, we aim to construct different structure variants of the G-CSF receptor containing different domains and select the best variant that prevents the adverse actions of this chemokine. These novel structures are smaller than antibodies and easier to produce.

Experimental approach:

Different domains of the G-CSF receptor were designed and cloned into the pET28a expression vector. These recombinant receptor subunits were then expressed in Escherichia coli and purified using standard affinity chromatography techniques. Interaction of recombinant receptor subunits with G-CSF was assessed using enzyme-linked immunosorbent assay and NFS60 cells.

Findings / Results:

Two recombinant receptor subunits containing D1 + D2 + D3 domains and D2 domain showed the strongest inhibitory activity to G-CSF.

Conclusion and implications:

These novel recombinant receptor variants could be candidates for further studies in the development of novel therapeutics.

Targeting Receptor Kinases in Colorectal Cancer

Colorectal cancer is the third most common malignancy in men and the second most common cancer in women. Despite the success of screening programs and the development of adjuvant therapies, the global burden of colorectal cancer is expected to increase by 60% to more than 2.2 million new cases and 1.1 million deaths by 2030. In recent years, a great effort has been made to demonstrate the utility of protein kinase inhibitors for cancer treatment. Considering this heterogeneous disease is defined by mutations that activate different Receptor Tyrosine Kinases (RTKs) and affect downstream components of RTK-activated transduction pathways, in this review we analyze the potential utility of different kinase inhibitors for colorectal cancer treatment.

The dark side of granulocyte-colony stimulating factor: a supportive therapy with potential to promote tumour progression

Granulocyte-colony stimulating factor (G-CSF) is one of several cytokines that can expand and mobilize haematopoietic precursor cells from bone marrow. In particular, G-CSF mobilizes neutrophils when the host is challenged by infection or tissue damage. Severe neutropenia, or febrile neutropenia is a life-threatening event that can be mitigated by administration of G-CSF. Consequently, G-CSF has been used to support patients undergoing chemotherapy who would otherwise require dose reduction due to neutropenia. Over the past 10-15 years it has become increasingly apparent, in preclinical tumour growth and metastasis models, that G-CSF can support tumour progression by mobilization of tumour-associated neutrophils which consequently promote tumour dissemination and metastasis. With the increasing use of G-CSF in the clinic, it is pertinent to ask if there is any evidence of a similar promotion of tumour progression in patients. Here, we have reviewed the preclinical and clinical data on the potential contribution of G-CSF to tumour progression. We conclude that, whilst the evidence for a promotion of metastasis is strong in preclinical models and that limited data indicate that high serum G-CSF levels in patients are associated with poorer prognosis, no studies published so far have revealed evidence of increased tumour progression associated with supportive G-CSF use during chemotherapy in patients. Analysis of G-CSF receptor positive cohorts within supportive trials, as well as studies of the role of G-CSF blockade in appropriate tumours in the absence of chemotherapy could yield clinically translatable findings.

Comparative transcriptomic analysis of porcine peripheral blood reveals differentially expressed genes from the cytokine-cytokine receptor interaction pathway related to health status

While some research has looked into the host genetic response in pigs challenged with specific viruses or bacteria, few studies have explored the expression changes of transcripts in the peripheral blood of sick pigs that may be infected with multiple pathogens on farms. In this study, the architecture of the peripheral blood transcriptome of 64 Duroc sired commercial pigs, including 18 healthy animals at entry to a growing facility (set as a control) and 23 pairs of samples from healthy and sick pen mates, was generated using RNA-Seq technology. In total, 246 differentially expressed genes were identified to be specific to the sick animals. Functional enrichment analysis for those genes revealed that the over-represented gene ontology terms for the biological processes category were exclusively immune activity related. The cytokine-cytokine receptor interaction pathway was significantly enriched. Nine functional genes from this pathway encoding members (as well as their receptors) of the interleukins, chemokines, tumor necrosis factors, colony stimulating factors, activins, and interferons exhibited significant transcriptional alteration in sick animals. Our results suggest a subset of novel marker genes that may be useful candidate genes in the evaluation and prediction of health status in pigs under commercial production conditions.

Recombinant Human Granulocyte Colony-Stimulating Factor Promotes Preinvasive and Invasive Estrogen Receptor-Positive Tumor Development in MMTV-erbB2 Mice

PURPOSE

We investigated whether recombinant human granulocyte colony-stimulating factor (rhG-CSF) could promote the development of preinvasive and invasive breast cancer in mouse mammary tumor virus (MMTV-erbB2) mice with estrogen receptor-positive tumors.

METHODS

MMTV-erbB2 mice were randomly divided into three experimental groups with 20 mice in each group. MMTV-erbB2 mice were treated with daily subcutaneous injections of vehicle or rhG-CSF (low-rhG-CSF group, rhG-CSF 0.125 µg; vehicle-rhG-CSF group, normal saline 0.25 µg; and high-rhG-CSF group, rhG-CSF 0.25 µg) at 3 months of age. Cellular and molecular mechanisms of G-CSF action in mammary glands were investigated via immunohistochemistry and reverse transcription polymerase chain reaction.

RESULTS

Low, but not high, rhG-CSF doses significantly accelerated mammary tumorigenesis in MMTV-erbB2 mice. Short-term treatment with rhG-CSF could significantly promote the development of preinvasive mammary lesions. The cancer prevention effect was associated with reduced expression of proliferating cell nuclear antigen, cluster of differentiation 34, and signal transducers and activators of transcription 3 in mammary glands by >80%.

CONCLUSION

We found that G-CSF was regulated by rhG-CSF both in vitro and in vivo. Identification of G-CSF genes helped us further understand the mechanism by which G-CSF promotes cancer. Low doses of rhG-CSF could significantly increase tumor latency and increase tumor multiplicity and burden. Moreover, rhG-CSF effectively promotes development of both malignant and premalignant mammary lesions in MMTV-erbB2 mice.

Preoperative Leukocytosis in Colorectal Cancer Patients

BACKGROUND

Preoperative asymptomatic leukocytosis has been reported as a factor that affects morbidity of surgical patients. We sought to identify the relationship between asymptomatic preoperative leukocytosis and postoperative complications in elective colorectal cancer surgery.

STUDY DESIGN

The NSQIP database was used to examine the clinical data of patients who had preoperative leukocytosis (white blood cell count more than 11,000/μL) and colorectal cancer resection from 2005 to 2013. Patients with preoperative sepsis, recent steroid use, disseminated cancer, renal failure, pneumonia, and emergently admitted patients were excluded from the study. Multivariate regression analysis was performed to identify outcomes of preoperative leukocytosis.

RESULTS

We evaluated a total of 59,805 patients with a diagnosis of colorectal cancer who underwent colorectal resection. The rate of preoperative asymptomatic leukocytosis was 5.6%. Asymptomatic leukocytosis was associated with preoperative serum albumin level (adjusted odds ratio [AOR] 0.58, p < 0.01) and blood urea nitrogen/creatinine ratio (AOR 1.01, p < 0.01). Preoperative asymptomatic leukocytosis had significant associations with increased mortality (AOR 1.76, p < 0.01) and morbidity of patients (AOR 1.26, p < 0.01). Postsurgical complications that had the strongest associations with asymptomatic leukocytosis were cardiac arrest (AOR 1.78, p = 0.03) and unplanned intubation (AOR 1.61, p < 0.01). Also, infectious complications were significantly higher in patients with leukocytosis (AOR 1.18, p = 0.01).

CONCLUSIONS

Preoperative asymptomatic leukocytosis has a prevalence of 5.6% in colorectal cancer resections and carries a significant increased risk of mortality and morbidity. Asymptomatic leukocytosis is associated with preoperative dehydration and malnutrition. Further studies are indicated to validate and explain these findings.

rhCSF3 accelerates the proliferation of human melanocytes in culture through binding CSF3R and the expression of CSF3R transcripts

Melanogenic paracrine and autocrine cytokine networks have recently been discovered in vitro between melanocytes and other types of skin cells. Granulocyte colony-stimulating factor receptor (CSF3R) controls the survival, proliferation and differentiation of many kinds of cells, including neutrophils. To understand the function of CSF3R and recombinant human granulocyte colony-stimulating factor (rhCSF3) on melanocyte proliferation, this study compared the expression of CSF3R and the effects of rhCSF3 in primary human melanocytes, neutrophils and HEL 92.1.7 cells. The results show that CSF3R is localized in the cytoplasm and on cell membranes of melanocytes and neutrophils. The percentage of CSF3R(+) melanocytes was higher than CSF3R(+) HEL 92.1.7 cells, but was lower than CSF3R(+) neutrophils. Both CSF3R mRNA and CSF3R protein levels in melanocytes were higher than in HEL 92.1.7 cells, but were lower than in neutrophils. Treatment with rhCSF3 increased the proliferation of human melanocytes, but not their tyrosinase activity. Transcripts of CSF3R in human melanocytes, M14, A375 melanoma and A431 squamous cell carcinoma cells were also detected. Expression of the CSF3R V3 transcript was lower in melanocytes than in M14, A375 melanoma and A431 squamous cell carcinoma cells. In conclusion, rhCSF3 can promote melanocyte proliferation through CSF3R without affecting tyrosinase activity.

Aberrant regulation of FBW7 in cancer

FBW7 (F-box and WD repeat domain-containing 7) or Fbxw7 is a tumor suppressor, which promotes the ubiquitination and subsequent degradation of numerous oncoproteins including Mcl-1, Cyclin E, Notch, c- Jun, and c-Myc. In turn, FBW7 is regulated by multiple upstream factors including p53, C/EBP-δ, EBP2, Pin1, Hes-5 and Numb4 as well as by microRNAs such as miR-223, miR-27a, miR-25, and miR-129-5p. Given that the Fbw7 tumor suppressor is frequently inactivated or deleted in various human cancers, targeting FBW7 regulators is a promising anti-cancer therapeutic strategy.

The Multifaceted Roles Neutrophils Play in the Tumor Microenvironment

Neutrophils are myeloid cells that constitute 50-70 % of all white blood cells in the human circulation. Traditionally, neutrophils are viewed as the first line of defense against infections and as a major component of the inflammatory process. In addition, accumulating evidence suggest that neutrophils may also play a key role in multiple aspects of cancer biology. The possible involvement of neutrophils in cancer prevention and promotion was already suggested more than half a century ago, however, despite being the major component of the immune system, their contribution has often been overshadowed by other immune components such as lymphocytes and macrophages. Neutrophils seem to have conflicting functions in cancer and can be classified into anti-tumor (N1) and pro-tumor (N2) sub-populations. The aim of this review is to discuss the varying nature of neutrophil function in the cancer microenvironment with a specific emphasis on the mechanisms that regulate neutrophil mobilization, recruitment and activation.

Expression of granulocyte colony-stimulating factor receptor in rectal cancer

AIM: To evaluate whether granulocyte colony-stimulating factor receptor (G-CSFR) expression before preoperative irradiation can predict the radiosensitivity of rectal cancer.

METHODS: The expression of G-CSFR was examined, using immunohistochemistry, in biopsy specimens from 126 patients with locally advanced rectal adenocarcinoma before preoperative irradiation. Radiosensitivity was then evaluated according to the Rectal Cancer Regression Grading. Endoscopic inspection was used to detect the tumor area in each patient. General patient information, such as age, gender, lymph node status, tumor size and degree of differentiation was recorded. A statistical analysis was then performed to evaluate the correlation between clinical or pathological parameters and G-CSFR expression in tumors.

RESULTS: According to endoscopic inspection, the tumor area ranged from 4 to 48 cm² (median, 15 cm²). Positive G-CSFR immunoreactions (G-CSFR⁺) were observed in 85 specimens, and negative (G-CSFR^-) in 41. No significant differences were found in age, gender, tumor invasion, lymph node status and tumor size between G-CSFR⁺ and G-CSFR^- patients. G-CSFR expression was positively correlated with poor radiotherapy response (58.8% vs 75.6%, P = 0.014, r = 0.219). The proportion of well-differentiated tumors in G-CSFR⁺ and G-CSFR^- patients was 24.7% and 36.6%, respectively. Sphincter preservation was observed in 57.6% of G-CSFR⁺ patients and 78.5% of G-CSFR^- patients. Significant correlations were found between G-CSFR expression and tumor differentiation (24.7% vs 36.6%, P = 0.019, r = 0.210), as well as sphincter preservation (57.6% vs 78.5%, P = 0.044, r = 0.180).

CONCLUSION: The expression of G-CSFR before preoperative irradiation may predict the radiosensitivity of rectal cancer.

Downregulation of hematopoietic MUC1 during experimental colitis increases tumor-promoting myeloid-derived suppressor cells

PURPOSE

MUC1 is a tumor-associated antigen that is aberrantly expressed in cancer and inflammatory bowel disease (IBD). Even though immune cells express low MUC1 levels, their modulations of MUC1 are important in tumor progression. Consistent with previous clinical data that show increased myeloid-derived suppressor cells (MDSCs) in IBD, we now show that downregulation of MUC1 on hematopoietic cells increases MDSCs in IBD, similar to our data in tumor-bearing mice. We hypothesize that MDSC expansion in IBD is critical for tumor progression.

EXPERIMENTAL DESIGN

To mechanistically confirm the linkage between Muc1 downregulation and MDSC expansion, we generated chimeric mice that did not express Muc1 in the hematopoietic compartment (KO→WT). These mice were used in two models of colitis and colitis-associated cancer (CAC) and their responses were compared with wild-type (WT) chimeras (WT→WT).

RESULTS

KO→WT mice show increased levels of MDSCs during colitis and increased protumorigenic signaling in the colon during CAC, resulting in larger colon tumors. RNA and protein analysis show increased upregulation of metalloproteinases, collagenases, defensins, complements, growth factors, cytokines, and chemokines in KO→WT mice as compared with WT→WT mice. Antibody-mediated depletion of MDSCs in mice during colitis reduced colon tumor formation during CAC.

CONCLUSION

Development of CAC is a serious complication of colitis and our data highlight MDSCs as a targetable link between inflammation and cancer. In addition, the lack of MUC1 expression on MDSCs can be a novel marker for MDSCs, given that MDSCs are still not well characterized in human cancers.

Effects of granulocyte-colony stimulating factor and the expression of its receptor on various malignant cells

Background

Granulocyte-colony stimulating factor (G-CSF) is extensively used to improve neutrophil count during anti-cancer chemotherapy. We investigated the effects of G-CSF on several leukemic cell lines and screened for the expression of the G-CSF receptor (G-CSFR) in various malignant cells.

Methods

We examined the effects of the most commonly used commercial forms of G-CSF (glycosylated lenograstim and nonglycosylated filgrastim) on various leukemic cell lines by flow cytometry. Moreover, we screened for the expression of G-CSFR mRNA in 38 solid tumor cell lines by using real-time PCR.

Results

G-CSF stimulated proliferation (40-80% increase in proliferation in treated cells as compared to that in control cells) in 3 leukemic cell lines and induced differentiation of AML1/ETO+ leukemic cells. Among the 38 solid tumor cell lines, 5 cell lines (hepatoblastoma, 2 breast carcinoma, squamous cell carcinoma of the larynx, and melanoma cell lines) showed G-CSFR mRNA expression.

Conclusion

The results of the present study show that therapeutic G-CSF might stimulate the proliferation and differentiation of malignant cells with G-CSFR expression, suggesting that prescreening for G-CSFR expression in primary tumor cells may be necessary before using G-CSF for treatment.

Expression of human granulocyte colony stimulating factor (hG-CSF) in colon adenocarcinoma cell line (Caco-2)

Growth and progression of many cancer cells are mediated by alterations in the microenvironment often caused by an aberrant expression of growth factors and receptors. There is no report on expression of growth factor granulocyte colony-stimulating factor (G-CSF) in the experimental model, colon adenocarcinoma cell line (Caco2), that is commonly used in drug permeability assays. We hypothesize that in vitro, the Caco2 model is associated with a constitutive neo-expression of the hematopoietic G-CSF thereby causing an autocrine stimulation of Caco2 growth and proliferation in vitro. To test our hypothesis, we analyzed mRNA and protein expression of G-CSF in Caco2 cells using reverse transcriptase-PCR and SDS-PAGE. G-CSF mRNA and protein were detected in Caco2 cells. Expression of G-CSF protein was similar at different passages of this cell line. The expression of G-CSF has a significant role in the autocrine regulation of Caco2 cell growth and proliferation.

Aggressive undifferentiated colon carcinoma producing granulocyte-colony stimulating factor: report of a case

We report a rare case of granulocyte-colony stimulating factor (G-CSF)-producing undifferentiated carcinoma of the ascending colon. A 52-year-old Japanese man presented with a rapidly growing, aggressive abdominal tumor, and severe leukocytosis (63 000/mm(3)). The serum level of G-CSF was remarkably elevated to 640 pg/ml (normal, <18.1 pg/ml). The patient underwent palliative cytoreductive surgery for ascending colon carcinoma with lymph node and liver metastases. Histological examination revealed an undifferentiated carcinoma of the ascending colon. The tumor cells were positive for G-CSF on immunohistochemical staining. The leukocyte counts and G-CSF level decreased after surgery. Thus, we diagnosed G-CSF-producing colon carcinoma. His general condition deteriorated rapidly and he died of residual tumor growth on postoperative day 24.

Recombinant human granulocyte colony-stimulating factor reduces colonic epithelial cell apoptosis and ameliorates murine dextran sulfate sodium-induced colitis

OBJECTIVE

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) is a potentially effective therapy for Crohn's disease. The purpose of this study was to test the rhG-CSF in murine dextran sulfate sodium-induced colitis (DSS colitis).

MATERIAL AND METHODS

Murine colitis was induced by feeding with water containing 3% DSS for 9 days. Six to 7-week-old female BALB/c mice were given rhG-CSF (100 microg/kg) or phosphate-buffered saline (PBS) subcutaneously once a day from day 0 to day 8, and the mice were sacrificed at days 3, 5, 7 and 9. Tissue specimens from the transverse colon, descending colon and rectum were obtained and stained with hematoxylin and eosin. Inflammation was scored for severity, extent, epithelial damage and crypt loss. TUNEL staining was performed to assess epithelial cell apoptosis.

RESULTS

Treatment with rhG-CSF significantly attenuated body-weight loss, stool score and shortening of the colon length in comparison with treatment with PBS (p<0.01,<0.05,<0.01, respectively). Histological scores for inflammation, epithelial cell damage and crypt loss of the rectum were less severe at day 9 in the rhG-CSF group than in the PBS group (p<0.01, 0.05, 0.01, respectively). The number of TUNEL-positive cells in the rectum was smaller in the rhG-CSF group than in the PBS group (p<0.001).

CONCLUSIONS

Treatment with rhG-CSF ameliorates murine DSS colitis by suppressing mucosal inflammation and epithelial damage in the rectum. The prevention of epithelial cell apoptosis seems to precede the anti-inflammatory action of rhG-CSF.

Granulocyte-colony stimulating factor producing rectal cancer

Background

Granulocyte-colony stimulating factor (G-CSF)-producing cancer has been reported to occur in various organs, especially the lung. However, G-CSF-producing colorectal cancer (CRC) has never been reported in the English literature.

Case presentation

A 57-year-old man was admitted for the surgical removal of a rectal cancer. Some hepatic tumors in the liver were revealed concurrently, and their appearance suggested multiple liver metastases. Low anterior resection was performed. with the help of histopathological examination and immunohistochemical studies, we diagnosed this case to be an undifferentiated carcinoma of the rectum. After the operation, the white blood cell (WBC) count increased gradually to 81,000 cells/μL. Modified-FOLFOX6 therapy was initiated to treat the liver metastases, but there was no effect, and peritoneal dissemination had also occurred. The serum level of G-CSF was elevated to 840 pg/mL (normal range, <18.1 pg/mL). Furthermore, immunohistochemistry with a specific monoclonal antibody against G-CSF was positive; therefore, we diagnosed this tumor as a G-CSF-producing cancer. The patient died from rapid growth of the liver metastases and peritoneal dissemination 2 months after surgery.

Conclusion

This is the first case of G-CSF-producing rectal cancer, and its prognosis was very poor.

Expression of granulocyte-colony-stimulating factor and its receptor in human Ewing sarcoma cells and patient tumor specimens: potential consequences of granulocyte-colony-stimulating factor administration

BACKGROUND

Ewing sarcoma (ES) is a highly vascular malignancy. It has been demonstrated that both angiogenesis and vasculogenesis contribute to the growth of ES tumors. Granulocyte-colony-stimulating factor (G-CSF), a cytokine known to stimulate bone marrow (BM) stem cell production and angiogenesis, is routinely administered to ES patients after chemotherapy. Whether ES cells and patient tumor samples express G-CSF and its receptor (G-CSFR) and whether treatment with this factor enhances tumor growth was examined.

METHODS

Human ES cell lines were analyzed for expression of G-CSF and G-CSFR in vitro and in vivo. Sixty-eight paraffin-embedded and 15 frozen tumor specimens from patients with ES were also evaluated for the presence of G-CSF and G-CSFR. The in vivo effect of G-CSF on angiogenesis and BM cell migration was determined. Using a TC/7-1 human ES mouse model, the effect of G-CSF administration on ES tumors was investigated.

RESULTS

G-CSF and G-CSFR protein and RNA expression was identified in all ES cell lines and patient samples analyzed. In addition, G-CSF was found to stimulate angiogenesis and BM cell migration in vivo. Tumor growth was found to be significantly increased in mice treated with G-CSF. The average tumor volume for the group treated with G-CSF was 1218 mm(3) compared with 577 mm(3) for the control group (P = .006).

CONCLUSIONS

The findings that ES cells and patient tumors expressed both G-CSF and its receptor in vitro and in vivo and that the administration of G-CSF promoted tumor growth in vivo suggest that the potential consequences of G-CSF administration should be investigated further.