Methylprednisolone versus intravenous immune globulin as an initial therapy in adult primary immune thrombocytopenia

BACKGROUND/AIMS

Few studies have addressed whether there are differences in clinical efficacy between intravenous methylprednisolone (methyl-Pd) and intravenous immunoglobulin (IVIg) use.

METHODS

We retrospectively compared platelet responses and toxicities associated with these two treatments in adult patients with immune thrombocytopenia. Patients received intravenous methyl-Pd therapy followed by oral prednisolone (Pd) from 1993 to 2002 and IVIg together with oral Pd from 2003 to 2008.

RESULTS

Early response and maintenance of the response were assessed at 7 days and 6 months after treatment, respectively. Of the 87 patients enrolled, 77 (88.5%) were eligible for analysis. Early responses occurred in 30 of 39 patients (76.9%) receiving methyl-Pd versus 33 of 38 patients (86.6%) receiving IVIg (p = 0.187). The response was maintained in 28 patients (71.8%) in the methyl-Pd arm and in 23 patients (60.5%) in the IVIg arm (p = 0.187). The time to a complete response in the IVIg arm (6 days; range, 1 to 35) was shorter than that in the methyl-Pd arm (13.5 days; range, 2 to 29) (p = 0.002). Side effects were mild and tolerable in both arms. Five years after initiating treatment, 7 of 18 patients (38.9%) and five of 14 patients (35.7%) were still maintaining a response in the methyl-Pd and IVIg arms, respectively.

CONCLUSION

These results indicate that neither the early response rate nor the long-term outcome differed between the methyl-Pd and IVIg treatments. However, IVIg induced a complete response more rapidly than did methyl-Pd.

The Derived Neutrophil-to-Lymphocyte Ratio Is an Independent Prognostic Factor in Transplantation Ineligible Patients with Multiple Myeloma

BACKGROUND

The neutrophil-to-lymphocyte ratio (NLR) is an independent prognostic marker in solid and hematological cancers. While the derived NLR (dNLR) was shown to be non-inferior to the NLR in large cohorts of patients with different cancer types, it has not been validated as a prognostic marker for multiple myeloma (MM) to date.

METHODS

Between May 22, 2011 and May 29, 2014, 176 patients with MM from 38 centers who were ineligible for autologous stem cell transplantation were analyzed. The dNLR was calculated using complete blood count differential data. The optimal dNLR cut-off value according to receiver operating characteristic analysis of overall survival (OS) was 1.51. All patients were treated with melphalan and prednisone combined with bortezomib.

RESULTS

The complete response rate was lower in the high dNLR group compared to the low dNLR group (7 vs. 26.1%, respectively; p = 0.0148); the corresponding 2-year OS rates were 72.2 and 84.7%, respectively (p = 0.0354). A high dNLR was an independent poor prognostic factor for OS (hazard ratio 2.217, 95% CI 1.015-4.842; p = 0.0458).

CONCLUSION

The dNLR is a readily available and cheaply obtained parameter in clinical studies, and shows considerable potential as a new prognostic marker for transplantation-ineligible patients with MM.

A prospective, open-label, multicenter, observational study to evaluate the efficacy and safety of bortezomib-melphalan-prednisone as initial treatment for autologous stem cell transplantation-ineligible patients with multiple myeloma

Bortezomib-melphalan-prednisone (VMP) showed superior efficacy versus MP as first-line treatment for transplantation-ineligible multiple myeloma (MM). This study investigated the efficacy of VMP for Korean patients with MM.

Overall, 177 MM patients received 9 cycles of VMP in this prospective, multicenter, observational study. The primary endpoint was 2-year progression-free survival (PFS).

Thirty-nine (22%) patients were aged ≥ 75 years and 83 (47.4%) patients had International Staging System stage III. A median of 5 cycles were delivered. Overall response rate (ORR) was 72.9%, and complete response (CR) rate was 20.3%. With a median follow-up of 11.9 months, median PFS was 17 months. The 2-year PFS and overall survival (OS) rates were 29.2% and 80.0%, respectively. Median OS was not reached. PFS was significantly different depending on performance status (Eastern Cooperative Oncology Group < 2 vs. ≥ 2; p = 0.0002), β₂-microglobulin level (< 5.5 vs. ≥ 5.5 mg/L; p = 0.0481), and cumulative dose of bortezomib (< 35.1 vs. ≥ 35.1 mg/m²; p < 0001). The common adverse events (AEs) were in line with the well-known toxicity profiles associated with VMP.

In conclusion, VMP is a feasible and effective front-line treatment for transplant-ineligible older patients with MM in Korea. Continuing therapy with prompt adjustment of treatment according to AEs may be important to improve outcomes of elderly patients.

Abstract 3947: Atypical chemokine receptor ACKR3 expression is associated with aggressive behavior and poor prognosis in gastric cancer

Chemokine and their receptors are key mediators of normal physiology and a large number of pathologic conditions such as cancer, and this family of receptors is the emerging therapeutic target in the field of cancer treatment. ACKR3 is an atypical chemokine receptor first cloned from a dog cDNA library as the orphan receptor and was initially named Receptor Dog cDNA 1 (RDC1). Shortly after demonstrating that RDC1 binds with its ligand, stromal cell-derived factor-1α (SDF-1α) and interferon-inducible T-cell α chemoattractant (I-TAC), RDC1 was officially deorphanized. Accumulating evidence of recent studies have suggested that expression of ACKR3 is augmented in most of tumor cells as compared to their normal counterparts and is involved in cell proliferation, survival, migration, invasion during the initiation and progression of cancer. However, there is little information regarding their expression and clinical relevance in gastric cancer. The expression status of ACKR3 was investigated in 221 specimens of primary gastric cancer using immunohistochemistry. The correlation of ACKR3 expression with the clinicopathological features and survival outcomes was analyzed as well. Immunohistochemical staining of gastric cancer tissue sections revealed diverse cytoplasmic and membrane staining patterns for ACKR3. One hundred-fourteen cases (51.6%) showed low ACKR3 expression according to an arbitrary scoring system (grade 0-1; grade 0, n = 26; grade 1, n = 88), and one hundred-seven cases (48.4%) showed high expression (grade 2-3; grade 2, n = 58; grade 3, n = 49). There were no significant differences in age, gender, histology, tumor location, lymphatic and venous invasion among the two groups. However, high CXCR7 expression in cancer cells tended to be associated with proportion of tumor size greater than 5 cm (P = 0.055) and was significantly correlated with depth of tumor invasion (P &lt; 0.001), lymph node metastasis (P = 0.042), and higher stage (P = 0.002). Furthermore, patients with high ACKR3 expression showed worse overall survival rate of 47% compared to 56% in patients with low ACKR3 expression. In conclusion, ACKR3 is differentially expressed in gastric cancer cells, and high expression of ACKR3 is associated with aggressive tumor behavior and poor survival in patients with gastric cancer, suggesting that ACKR3 plays an important role during gastric cancer progression.

Citation Format: Nayoung Kim, Seung-Woo Baek, Hyewon Ryu, Yoon Seok Choi, Ik Chan Song, Hwan Jung Yun, Deog Yeon Jo, Samyong Kim, Hyo Jin Lee. Atypical chemokine receptor ACKR3 expression is associated with aggressive behavior and poor prognosis in gastric cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3947.

Loss of NDRG2 promotes epithelial-mesenchymal transition of gallbladder carcinoma cells through MMP-19-mediated Slug expression

BACKGROUND & AIMS

Gallbladder carcinoma (GBC) is the most common malignancy of the biliary tract and one of the most lethal forms of human cancer. However, there is limited information about the molecular pathogenesis of GBC. Here, we examined the functional role of the tumor suppressor N-myc downstream-regulated gene 2 (NDRG2) and the underlying molecular mechanisms of disease progression in GBC.

METHODS

Clinical correlations between NDRG2 expression and clinicopathological factors were determined by immunohistochemical analysis of tumor tissues from 86 GBC patients. Biological functions of NDRG2 and NDRG2-mediated signaling pathways were determined in GBC cell lines with NDRG2 knockdown or overexpression.

RESULTS

Loss of NDRG2 expression was an independent predictor of decreased survival and was significantly associated with a more advanced T stage, higher cellular grade, and lymphatic invasion in patients with GBC. GBC cells with loss of NDRG2 expression showed significantly enhanced proliferation, migration, and invasiveness in vitro, and tumor growth and metastasis in vivo. Loss of NDRG2 induced the expression of matrix metalloproteinase-19 (MMP-19), which regulated the expression of Slug at the transcriptional level. In addition, MMP-19-induced Slug, increased the expression of a receptor tyrosine kinase, Axl, which maintained Slug expression through a positive feedback loop, and stabilized epithelial-mesenchymal transition of GBC cells.

CONCLUSIONS

The results of our study help to explain why the loss of NDRG2 expression is closely correlated with malignancy of GBC. These results strongly suggest that NDRG2 could be a favorable prognostic indicator and promising target for therapeutic agents against GBC.

Early response to bortezomib combined chemotherapy can help predict survival in patients with multiple myeloma who are ineligible for stem cell transplantation

Novel agents to treat multiple myeloma (MM) have increased complete respone (CR) rates compared with conventional chemotherapy, and the quality of the response to treatment has been correlated with survival. The purpose of our study was to show how of early response to bortezomib combined chemotherapy influences survival in patients with newly diagnosed MM who are ineligible for stem cell transplantation. We assessed patient responses to at least four cycles of bortezomib using the International Myeloma Working Group response criteria. The endpoints were comparisons of progression free survival (PFS) and overall survival (OS) between early good response group (A group) and poor response group (B group). We retrospectively analyzed data from 129 patients registered by the Korean Multiple Myeloma Working Party, a nationwide registration of MM patients. The 3 yr PFS for the A and B groups was 55.6% and 18.4%, respectively (P < 0.001). The 3 yr OS for the A and B groups was 65.3% and 52.9%, respectively (P = 0.078). The early response to at least four cycle of bortezomib before next chemotherapy may help predict PFS in patients with MM who are ineligible stem cell transplantation.

The role of the CXCR4/CXCL12 axis and its clinical implications in gastric cancer

Gastric cancer is the second leading cause of cancer deaths worldwide. Despite the extensive body of research on gastric cancer, the prognosis of patients with advanced gastric cancer remains poor, and therapy for advanced gastric cancer relies largely on cytotoxic chemotherapy. Therefore, identifying the distinct molecular pathways underlying disease progression and treatment resistance may lead to novel therapeutic approaches, as well as improve the quality of life and survival of patients. The chemokine CXCL12 and its receptor CXCR4 are now known to play an important role in cancer development and progression. Here, we review the expression and function of CXCR4 and CXCL12, as well as their clinical relevance in gastric cancer. We also cover the current molecular mechanism, specifically the cell-signaling pathway, by which gastric cancer progresses through the CXCR4/CXCL12 axis, and discuss the potential of that axis as a therapeutic target in the treatment of gastric cancer.

Transitional cell carcinoma of the urinary bladder metastatic to the oral mucosa

Metastatic tumors in the oral cavity are rare and usually affect the jaws more often than the oral soft tissues. In particular, metastases confined to the oral mucosa are extremely rare and originate mainly from the lung and breast. Only one case restricted to the oral mucosa and originating from urinary bladder carcinoma has previously been described. We report on a painful polypoid mass located in the oral mucosa with no bone involvement that was confirmed to be a metastatic oral tumor that originated from transitional cell carcinoma of the urinary bladder and progressed rapidly.

Chemokine (C-X-C motif) ligand 12 is associated with gallbladder carcinoma progression and is a novel independent poor prognostic factor

PURPOSE

Although recent studies have suggested that chemokine (C-X-C motif) ligand 12 (CXCL12) is important in the progression of various malignancies, its role in gallbladder carcinoma (GBC) remains unknown. We investigated CXCL12 expression in GBC and its biologic and prognostic role in GBC tumorigenesis.

EXPERIMENTAL DESIGN

We examined CXCL12 expression in tumor specimens from 72 patients with GBC by immunohistochemistry and analyzed the correlation between CXCL12 expression and clinicopathologic factors or survival. The functional significance of CXCL12 expression was investigated by CXCL12 treatment and suppression of CXCR4, a major receptor of CXCL12, as well as by CXCL12 overexpression in in vitro and in vivo studies.

RESULTS

CXCL12 was differentially expressed in GBC tissues. CXCL12 expression was significantly associated with a high histologic grade (P = 0.042) and nodal metastasis (P = 0.015). Multivariate analyses showed that CXCL12 expression (HR, 8.675; P = 0.014) was an independent risk factor for patient survival. CXCL12 significantly increased anchorage-dependent and -independent growth, migration, invasion, adhesiveness, and survival of GBC cells in vitro, and these effects were dependent on CXCR4. Consistent with these results, overexpression of CXCL12 significantly promoted GBC tumorigenicity in a xenograft model.

CONCLUSIONS

Our results indicate that GBC cells express both CXCL12 and its receptor CXCR4, and CXCL12 may have a role in GBC progression through an autocrine mechanism. In addition, CXCL12 is a novel independent poor prognostic factor in patients with GBCs. Thus, targeting CXCL12 and CXCR4 may provide a novel therapeutic strategy for GBC treatment.

Abstract 1201: Hypoxia promotes not CXCR7 but CXCR4 expression and its biological activity in gastric cancer cell through activation of hypoxia-inducible factor-1β

Background: The chemokine receptor, CXCR4 and CXCR7, which bind with high affinity same chemokine CXCL12/SDF-1, are associated with the biological behavior in several kinds of cancer, but few studies have addressed the expression and regulation of CXCR4 and CXCR7 in gastric cancer. Methods: Gastric cancer cell line KATO III was subjected to hypoxia or normoxia. The expression of CXCR4 and CXCR7 were investigated using RT-PCR, Westerning blotting, and flow cytometry before and after hypoxic conditioning. The regulation of CXCR4 and CXCR7, and their biological effects by hypoxia were evaluated using gastric cancer cells transfected with hypoxia-inducible factor (HIF)-1α shRNA. Result: mRNA and proteins of both CXCR4 and CXCR7 were detectable by RT-PCR and Western blot analysis, respectively, in KATO III cells. A small population of KATO III cells expressed membrane CXCR4 and CXCR7 as determined by flow cytometry. Hypoxia up-regulated CXCR4 proteins and enhanced membrane expression of CXCR4 in human gastric cancer KATO III cells, which constitutively expressed membrane CXCR7 and CXCR4 in a steady state, as revealed by Western blotting and flow cytometry, respectively. In contrast, CXCR7 proteins remained unchanged under hypoxia, and promotion of CXCR7 surface expression on KATO III cells could not be demonstrated by flow cytometry. Hypoxia-induced expression of CXCR4 was mediated through activation of HIF-1α with phosphorylation of AKT and ERK, as revealed by HIF-1α knockdown using shRNA. The chemical inducer of HIF-1α, cobalt chloride, induced upregulation of CXCR4 in KATO III cells under normoxic conditions. In addition, KATO III cells exposed to hypoxic condition showed enhanced wound healing, transwell migration, and invasion in response to stromal cell-derived factor (SDF)-1α, a specific ligand for CXCR4. Conclusions: These findings provide evidences for differential regulation and different role of chemokine receptor, CXCR7 and CXCR4, in gastric cancer cell in vitro.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1201. doi:1538-7445.AM2012-1201

Abstract 2269: Loss of NDRG2 expression is an independent prognostic factor in patients with localized clear cell renal cell carcinoma

Background: NDRG2 is a candidate tumor suppressor because it induced apoptosis and was down-regulated or absent in some cancers. About renal cell carcinoma it has been reported that NDRG2 inhibit the proliferation of clear cell RCC (CCRCC) cell and induce arrest at G1 phase. Moreover, NDRG2 were down-regulated in fresh CCRCC tissues, suggesting NDRG2 may play an important role in the development of CCRCC as a tumor suppressor. However, the clinical effect of NDRG2 expression in RCC has not been previously investigated.

Method: NDRG2 mAb was generated using recombinant protein consisting of aminoacids 150-337 of NDRG2 (NM_201541). The expression of NDRG2 proteins were studied by immunohistochemistry in 112 TMA of patients who underwent nephrectomy for localized CCRCC. Tumors were classified into four grades based on the staining intensity (0, no staining intensity; +1, weak; +2, intermediate; +3, strong). The cases with 0 staining intensity were considered the NDRG2-negative group, whereas those with +1 to +3 staining intensity were considered the NDRG2-positive group. Correlations between NDRG2 expression and clinicopathologic features as well as patient survival were determined.

Results: A total of 7 cases (6.3%) showed 0 staining intensity (NDRG2-negative group), whereas 105 cases showed +1 (35 cases), +2 (33 cases), or +3 (37 cases) staining intensity (NDRG2-positive group). NDRG2-negative tumors tended to show higher T stage (pT2-3) compared to NDRG2-positive group (85.7% vs. 55.2%). Furthermore, NDRG2-negative group was significantly associated with higher proportion of tumor larger than 10 cm (P = .012) and higher nuclear grade (P = .003). About survival, the 5-year recurrence-free survival (RFS) rates of the NDRG2-positive and -negative group were 86.7% and 28.6%, respectively (P &lt; .001), and the rates of 5-year disease-specific survival (DSS) for NDRG2-positive and -negative group were 92.4% and 28.6%, respectively (P &lt; .001). Univariate analyses indicated that Fuhrman nuclear grade (P = .009) and loss of NDRG2 expression (P &lt; .001) were statistically significant risk factors affecting RFS of CCRCC patients. About DSS, Fuhrman nuclear grade (P = .005) and loss of NDRG2 expression (P &lt; .001) were also significant risk factors. Furthermore, Multivariate analyses showed that Fuhrman nuclear grade (HR, 2.990; P = .025) and loss of NDRG2 expression (HR, 7.901; P &lt;.001) were independent risk factors predicting RFS of CCRCC patients. Loss of NDRG2 expression was still an independent prognostic factor (HR, 15.395; P &lt; .001) for DSS.

Conclusion: NDRD2 expression was lost in some population of CCRCC patients, and loss of NDRG2 expression was correlated with larger tumor size and higher nuclear grade. Furthermore, loss of NDRG2 expression was an independent poor prognostic factor predicting RFS and DSS, suggesting that it could be a useful marker to predict outcomes in patients with CCRCC.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2269. doi:10.1158/1538-7445.AM2011-2269

Evaluation of the combined expression of chemokine SDF-1α and its receptor CXCR4 as a prognostic marker for gastric cancer

Chemokine stromal cell-derived factor (SDF)-1α and its receptor CXC chemokine receptor 4 (CXCR4) have been shown to impact cancer progression. Accumulating evidence suggests that CXCR4 and SDF-1α expression is useful for evaluating the risk of gastric cancer progression. Thus, combined analysis of SDF-1α and CXCR4 should have high prognostic potential as a molecular marker for gastric cancer. We investigated the expression of SDF-1α and CXCR4 using immunohistochemistry in relation to prognosis, clinicopathological features and clinical outcomes in 221 cases of primary gastric cancer. Patients were categorized into three groups according to CXCR4 and SDF-1α expression: high CXCR4/high SDF-1α, low CXCR4/low SDF-1α, and high CXCR4/low SDF-1α - low CXCR4/high SDF-1α. No significant differences were noted in age, gender, histology, tumor location, lymphovascular invasion or proportion of tumor size >5 cm among the three groups. However, high CXCR4/high SDF-1α expression in tumor cells was significantly associated with depth of invasion of the tumor, lymph node involvement, and higher tumor stage compared to tumors with low CXCR4/low SDF-1α expression or high CXCR4/low SDF-1α - low CXCR4/high SDF-1α expression. Furthermore, patients with high CXCR4/high SDF-1α expression had the worst patient prognosis, whereas patients who had low CXCR4/low SDF-1α expression showed the most favorable prognosis. In conclusion, CXCR4 and SDF-1α are useful prognostic factors in gastric cancer, and the combination of high CXCR4 protein expression with high SDF-1α expression suggests a dismal prognosis.

A prospective evaluation of adult men with iron-deficiency anemia in Korea

OBJECTIVE

Iron-deficiency anemia (IDA) is the most common nutritional deficiency worldwide. However, the information concerning various causes of IDA in adult men is still insufficient. The aim of our study was to evaluate adult men with IDA.

METHODS

We prospectively studied 206 adult men with IDA. All subjects had a direct history taken and underwent a physical examination. Esophagogastroduodenoscopy was performed in most patients, and colonoscopy was conducted if no lesion causing IDA was found or the fecal occult blood test was positive.

RESULTS

The history of prior gastrectomy and blood-letting cupping therapy that probably had caused IDA were reported in 24 (11.7%) and 11 (5.3%) patients, respectively. In terms of potential causes of IDA, 68 (33.0%) patients were found to have upper gastrointestinal disorders (34 peptic ulcers, 17 erosive gastritis, 16 gastric cancers, and one gastrointestinal stromal tumor). Colonoscopy showed 42 (20.4%) clinically relevant lesions that probably caused IDA: colon cancer (five patients), colon polyps (14 patients), ulcerative colitis (one patient), and hemorrhoids (22 patients). One small bowel tumor was detected at small bowel series. Concerning malignant lesions that were responsible for IDA, 22 malignant lesions were found in patients of 50 years or older, accounting for 16.8% (22 of 131 patients), while only one (1.3%) early gastric cancer was found in the younger patients.

CONCLUSION

This study demonstrated that gastrointestinal blood loss is the main cause of IDA in adult men, and that there is a high rate of malignancy in men older than 50 years, emphasizing the need for a complete, rigorous gastrointestinal examination in this group of patients. Considering blood-letting cupping therapy, there is a need to consider culture-specific procedures as a possible cause of IDA.

Fas and FasL polymorphisms are not associated with acute myeloid leukemia risk in Koreans

Fas and Fas ligand (FasL) polymorphisms in the promoter regions influence transcriptional activities. The interaction of these two genes plays a crucial role in apoptotic cell death regulation. They have been associated with esophageal, lung, uterine cervical, and urinary bladder cancers in human. We performed a case-control study to investigate the association between Fas and FasL polymorphisms and acute myeloid leukemia (AML) risk. Fas−1377G>A (rs2234767), −670T>C (rs1800682), and FasL−844T>C (rs763110) polymorphisms in 592 AML patients and 858 healthy controls were genotyped and tested for associations between polymorphisms and AML risk. There were no significant differences in genotypic and haplotypic distributions and gene-gene interaction between patients and controls in the overall analysis (p>0.05). These results suggested that polymorphisms of Fas and FasL genes were not associated with AML risk in the Korean population.

Chemokine receptor CXCR4 expression, function, and clinical implications in gastric cancer

The chemokine receptor CXCR4 is associated with the biological behavior of cancer, but few studies have addressed the expression and function of CXCR4 in human gastric cancer and its impact on disease prognosis. We studied the expression of CXCR4 using RT-PCR, Western blotting, flow cytometry, and confocal microscopy in five gastric cancer cell lines. We also examined cell proliferation, migration, and anti-apoptotic activity in response to stromal cell-derived factor (SDF)-1alpha and evaluated SDF-1alpha/CXCR4 signaling pathways. Furthermore, we investigated the correlation between CXCR4 expression and the clinical features of 221 gastric cancer tissue samples. CXCR4 transcripts and proteins were detectable in all five gastric cancer cell lines. However, MKN-28, MKN-45, MKN-74, and SNU16 cells did not express membrane CXCR4. In contrast, KATO III cells expressed membrane CXCR4. In these cells, SDF-1alpha-induced migration was observed and was blocked by AMD3100, a specific inhibitor of CXCR4. SDF-1alpha induced rapid phosphorylation of Erk1/2 MAPK but did not promote phosphorylation of Stat3 or Akt. Gastric cancer tissue samples expressed CXCR4 with variable intensities. Strong CXCR4 expression was significantly associated with lymph node metastases (P=0.028) and higher stages III/IV (P=0.047), and further tended to be correlated with a reduced 5-year survival rate (42.6% vs. 53.9%; P=0.1). In conclusion, CXCR4 expression is associated with gastric cancer cell migration in vitro, and strong expression of CXCR4 by gastric cancer cells is significantly associated with lymphatic metastasis in patients with gastric cancer, suggesting that CXCR4 plays an important role during gastric cancer progression.

Polymorphisms involved in the folate metabolizing pathway and risk of multiple myeloma

Folate and methionine metabolism plays an essential role in both DNA synthesis and methylation. Polymorphisms in the genes of the folate-dependent enzymes have been shown to affect disease susceptibility. We conducted a Korean population-based case-control study to evaluate whether genetic variation in folate metabolism may have a role in the risk of multiple myeloma (MM). The study subjects were 173 patients with MM and 1,700 population-based controls. The polymorphisms studied include methylenetetrahydrofolate reductase (MTHFR) 677 C > T and 1298 A > C, methionine synthase (MS) 2756 A > G, methionine synthase reductase (MTRR) 66A > G, thymidylate synthase (TS) 28-bp repeat (2R-->3R) and 6-bp deletion/insertion. MS 2756 AG genotypes were associated with a 1.5-fold lower risk of MM (OR = 0.66, 95%CI; 0.43-0.99, P = 0.047). There was no association between MTHFR C677T, A1298C, MTRR A66G, TS 2R-->3R and 6-bp deletion/insertion polymorphisms and MM. These results suggest that MTHFR C677T, A1298C, MTRR A66G, TS 2R-->3R, and 6-bp deletion/insertion do not significantly factor into the pathogenesis of MM in the Korean population, but that MS A2756G polymorphism may play an important role.

Monosomy 7 as the sole abnormality of an acute basophilic leukemia

We report the case of a 72-year-old man who had the very rare disease acute basophilic leukemia with the sole chromosomal finding of a monosomy 7. Most nuclear cells in the peripheral blood and bone marrow samples were either basophils or blasts. The blasts showed negative reaction with myeloperoxidase, periodic acid Schiff, chloroacetate esterase, alpha-naphthyl butyrate esterase, acid phosphatase, and Sudan black B. Metachromatic features of the blasts, however, were observed with toluidine blue stain. Electron microscopic evaluation showed the typical ultrastructure, with basophil and immature mast cell granules. Cytogenetic study revealed monosomy 7 in all metaphase cells, and this finding was confirmed by fluorescence in situ hybridization. The Philadelphia chromosome was absent. Review of the literature revealed abnormalities in cases of ABL. To our knowledge, the case reported here is the first to have basophilic leukemia with monosomy 7 as the only chromosome abnormality.

A case of recurrent solid pseudopapillary tumor of the pancreas with involvement of the spleen and kidney

Solid pseudopapillary tumor of the pancreas (SPTP) is a rare primary pancreatic tumor of an unknown etiology that is usually diagnosed in adolescent girls and young women. Most SPTPs are considered to be benign and only rarely metastasize. We report here on a 27-year old woman with recurrent SPTP with involvement of both the spleen and left kidney at the time of the initial diagnosis, and with aggressive behavior. In July 1995, she was admitted with abdominal discomfort and mass. She underwent exploratory laparotomy with distal pancreatectomy, left nephrectomy and splenectomy, and was diagnosed with SPTP with invasion to both the spleen and left kidney. In June 2001, she again presented with abdominal pain and was diagnosed as having recurrence of the tumor. She underwent mass excision and omentectomy. Then she was lost to follow-up. In November 2005, she presented once again with an abdominal mass and was diagnosed with recurred SPTP, which formed a huge intraperitoneal mass with peritoneal seeding and the tumor showed multiple metastases in the liver. She is currently being treated conservatively.

CXC chemokine receptor 4 expression and function in human anaplastic thyroid cancer cells

Anaplastic thyroid carcinomas (ATCs) are highly aggressive, extremely lethal human cancers with poor therapeutic response. Chemokines are a superfamily of small cytokine-like proteins that induce, through their interaction with G protein-coupled receptors, cytoskeletal rearrangement, firm adhesion to endothelial cells, and directional migration. In this study, we characterized the expression of CXC chemokine receptor 4 (CXCR4) and analyzed its functions in ARO cells, a human ATC cell. The normal primary cultured thyroid cells and ATC cell lines expressed CXCR4 and stromal cell-derived factor (SDF)-1 alpha transcripts, detected by RT-PCR. Fluorescence activated cell sorting analysis of CXCR4 expression in normal and ATC cells showed that ARO cells expressed significant levels of CXCR4. FRO, NPA, and normal thyroid cells did not express membrane CXCR4, as determined by fluorescence activated cell sorting analysis. To identify the functional role of CXCR4 in ARO cells, we treated ARO cells with SDF-1 alpha and analyzed the signaling pathways, cellular migration, and proliferation. SDF-1alpha enhanced the migration but did not affect the proliferation of ARO cells or activate the Janus kinase/signal transducer and activator of transcription signaling pathways. However, SDF-1 alpha/CXCR4 activation resulted in phosphorylation of the p70S6 kinase and its target protein, ribosomal S6 protein, and also activation of the ERK1/ERK2 signaling pathways. Furthermore, SDF-1 alpha/CXCR4- mediated activation of the p70S6 kinase and phosphorylation of the S6 protein were inhibited by treatment with an mTOR/FRAP inhibitor. The specificity of the CXCR4-mediated migration of ARO cells was demonstrated by the dose-dependent inhibition of migration by neutralizing anti-CXCR4. The ATC cells, FRO and NPA, which do not express CXCR4, did not demonstrate significant SDF-1 alpha-mediated migration in vitro. In addition, the CXCR4-mediated migration of ARO cells was inhibited by treatment with pertussis toxin (a Gi-protein inhibitor) and PD 98059 (a mitogen-activated ERK kinase inhibitor) but not by LY294002 and wortmanin, phosphatidylinositol 3-kinase inhibitors. These findings suggest that a subset of ATC cells expresses functional CXCR4, which may be important in tumor cell migration and local tumor invasion.

Ex vivo expansion of stem and progenitor cells in co-culture of mobilized peripheral blood CD34+ cells on human endothelium transfected with adenovectors expressing thrombopoietin, c-kit ligand, and Flt-3 ligand

To optimize conditions for ex vivo expansion of adult hematopoietic stem cells, we evaluated the co-culture of G-CSF mobilized human peripheral blood (PB) CD34(+) cells with endothelial cells engineered to overexpress various hematopoietic growth factors. Immortalized human bone marrow endothelial cells (BMEC) transfected with an expression vector carrying cDNA encoding the human telomerase reverse transcriptase (hTERT) and human umbilical vein endothelial cells (HUVEC) were transfected with combinations of adenovectors expressing murine c-kit ligand (KL), human thrombopoietin (TPO), human Flt3 ligand (FL), and human granulocyte-macrophage colony-stimulating factor (GM-CSF). Ex vivo expansion of PB CD34(+) cells from normal donors and non-Hodgkin lymphoma (NHL) patients in endothelial co-culture was evaluated weekly for total cell production, progenitor (CFU-GM, BFU-E) cell production, and stem cell production as measured by Week-5 Cobblestone Area Forming Cell assay (Wk-5 CAFC). HUVEC transfected with adenovectors expressing TPO, KL, and FL provided the best co-culture system for expanding CD34(+) cells. Maximal total nuclear cell, CFU-GM, and Wk-5 CAFC production occurred between weeks 2 and 3 with 113-fold, 25-fold, and 2.2-5.5-fold expansions, respectively. We did not detect significant differences when GM-CSF was added to the co-culture system. Expansion was also obtained using recombinant human cytokines, but was not maintained beyond 3 weeks. We demonstrated that continuous generation of high levels of TPO, FL, and KL as well as other factors secreted by endothelium provided a clinically relevant co-culture method for ex vivo expansion of stem and progenitor cells from cryopreserved CD34(+) populations.

Chemotaxis of primitive hematopoietic cells in response to stromal cell-derived factor-1

Stromal cell-derived factor-1 (SDF-1) provides a potent chemotactic stimulus for CD34(+) hematopoietic cells. We cultured mobilized peripheral blood (PB) and umbilical cord blood (CB) for up to 5 weeks and examined the migratory activity of cobblestone area-forming cells (CAFCs) and long-term culture-initiating cells (LTC-ICs) in a transwell assay. In this system, SDF-1 or MS-5 marrow stromal cells placed in the lower chamber induced transmembrane and transendothelial migration by 2- and 5-week-old CAFCs and LTC-ICs in 3 hours. Transmigration was blocked by preincubation of input CD34(+) cells with antibody to CXCR4. Transendothelial migration of CB CAFCs and LTC-ICs was higher than that of PB. We expanded CD34(+) cells from CB in serum-free medium with thrombopoietin, flk-2 ligand, and c-kit ligand, with or without IL-3 and found that CAFCs cultured in the absence of IL-3 had a chemotactic response equivalent to noncultured cells, even after 5 weeks. However, addition of IL-3 to the culture reduced this response by 20-50%. These data indicate that SDF-1 induces chemotaxis of primitive hematopoietic cells signaling through CXCR4 and that the chemoattraction could be downmodulated by culture ex vivo.

Stromal derived factor-1-induced chemokinesis of cord blood CD34(+) cells (long-term culture-initiating cells) through endothelial cells is mediated by E-selectin

Homing of hematopoietic stem cells to the bone marrow (BM) involves sequential interaction with adhesion molecules expressed on BM endothelium (BMEC) and chemokine stromal derived factor-1 (SDF-1). However, the mechanism whereby adhesion molecules regulate the SDF-1-induced transendothelial migration process is not known. E-selectin is an endothelial-specific selectin that is constitutively expressed by the BMEC in vivo. Hence, we hypothesized that E-selectin may mediate SDF-1-induced transendothelial migration of CD34(+) cells. We show that CD34(+) cells express both E-selectin ligand and fucosyltransferase-VII (FucT-VII). Soluble E-selectin-IgG chimera binds avidly to 75% +/- 10% of CD34(+) cells composed mostly of progenitors and cells with long-term culture-initiating cell (LTC-IC) potential. To assess the functional capacity of E-selectin to mediate CD34(+) cell migration in a transendothelial migration system, CD34(+) cells were placed on transwell plates coated with interleukin-1beta-activated BMEC. In the absence of SDF-1, there was spontaneous migration of 7.0% +/- 1.4% of CD34(+) cells and 14.1% +/- 2.2% of LTC-IC. SDF-1 induced migration of an additional 23.0% +/- 4.4% of CD34(+) cells and 17.6% +/- 3.6% of LTC-IC. Blocking MoAb to E-selectin inhibited SDF-1-induced migration of CD34(+) cells by 42.0% +/- 2.5% and LTC-IC by 90.9% +/- 16.6%. To define the mechanism of constitutive expression of E-selectin by the BMEC in vivo, we have found that vascular endothelial growth factor (VEGF(165)) induces E-selectin expression by cultured endothelial cells. VEGF-stimulated endothelial cells support transendothelial migration of CD34(+) cells that could be blocked by MoAb to E-selectin. These results suggest that trafficking of subsets of CD34(+) cells with LTC-IC potential is determined in part by sequential interactions with E-selectin and SDF-1.