Paclitaxel-Ifosfamide-based Therapy as Salvage Treatment in Platinum-resistant Recurrent/Metastatic Head and Neck Cancer.

BACKGROUND: Treatment options are limited, and the prognosis is poor for patients with platinum-resistant recurrent metastatic (R/M) head and neck squamous cell carcinoma (HNSCC). This study evaluated the efficacy and safety of a paclitaxel and ifosfamide (TI) regimen in patients with R/M HNSCC whose disease had progressed following platinum-based therapy. PATIENTS AND METHODS: In this retrospective study, we included 53 patients with R/M HNSCC who underwent at least one cycle of TI-based therapy, post platinum failure, between February 2020 and August 2023. Some patients received the TI regimen in combination with immunotherapy and/or cetuximab. Key metrics assessed included the objective response rate (ORR), disease control rate, and progression-free as well as overall survival. RESULTS: The study observed an ORR of 15.8% and a disease control rate of 36.8%. The median progression-free survival for the entire cohort was 3.3 months, and the median overall survival was 9.6 months. Notably, the combination of TI with immunotherapy yielded a higher ORR of 30.8%, compared to 14.3% with TI alone. The most prevalent grade 1-2 adverse events were anemia (81%), weight loss (68%) and hypernatremia (55%). CONCLUSION: The TI-based regimen demonstrated favorable efficacy and safety profile in treating R/M HNSCC. Enhanced outcomes may be attainable when combining it with immunotherapy. This study suggests that TI-based therapy could serve as a potential salvage option for this specific patient group.

Clinical outcomes of cetuximab-based treatment for distant metastatic head and neck squamous cell carcinoma: A real-world study using Taiwan Head Neck Society registry database.

BACKGROUND: For R/M HNSCC, the differences in prognosis and treatment options between distant metastasis (DM) and locoregional recurrence, especially in the DM group, remain unclear. METHODS: From the Taiwan Head Neck Society registry database, patients who were diagnosed with R/M HNSCC and received cetuximab-based frontline therapy were collected for analysis. RESULTS: Among the enrolled patients, 59.3% (491/827) belonged to the DM group. The DM group had less primary site of oral cavity, less betel nut chewing, higher lactate dehydrogenase (LDH) levels, and higher LDH/albumin ratio compared with the non-DM group. For the patients with primary site of oral cavity and current smokers, DM coexisted with poorer outcomes. In the DM group, EXTREME-like regimen was more suitable for older patients, those with elevated LDH, and those with higher LDH/albumin ratio than TPExtreme-like regimen. CONCLUSION: DM coexisted with poorer prognosis in certain groups. LDH-associated biomarkers may aid treatment options for DM patients.

Elevated PD-L1 Expression and Microsatellite Instability in Elderly Patients With Gastric Cancer.

Immunotherapy in combination with chemotherapy is the current treatment of choice for frontline programmed cell death ligand 1 (PD-L1)-positive gastric cancer. However, the best treatment strategy remains an unmet medical need for elderly or fragile patients with gastric cancer. Previous studies have revealed that PD-L1 expression, Epstein-Barr virus association, and microsatellite instability-high (MSI-H) are the potential predictive biomarkers for immunotherapy use in gastric cancer. In this study, we showed that PD-L1 expression, tumor mutation burden, and the proportion of MSI-H were significantly elevated in elderly patients with gastric cancer who were older than 70 years compared with patients younger than 70 years from analysis of The Cancer Genome Atlas gastric adenocarcinoma cohort [≥70/<70: MSI-H: 26.8%/15.0%, P =0.003; tumor mutation burden: 6.7/5.1 Mut/Mb, P =0.0004; PD-L1 mRNA: 5.6/3.9 counts per million mapped reads, P =0.005]. In our real-world study, 416 gastric cancer patients were analyzed and showed similar results (≥70/<70: MSI-H: 12.5%/6.6%, P =0.041; combined positive score ≥1: 38.1%/21.5%, P <0.001). We also evaluated 16 elderly patients with gastric cancer treated with immunotherapy and revealed an objective response of 43.8%, a median overall survival of 14.8 months, and a median progression-free survival of 7.0 months. Our research showed that a durable clinical response could be expected when treating elderly patients with gastric cancer with immunotherapy, and this approach is worth further study.

Tumor-associated tissue eosinophilia promotes angiogenesis and metastasis in head and neck squamous cell carcinoma.

Eosinophils are terminally differentiated leukocytes that participate in the process of chronic inflammation and allergy and are able to release multiple cytokines into the surrounding tissue environment. Tumor-associated tissue eosinophilia (TATE) is the presence of eosinophils in the tumor or in the neighboring stroma and has been observed in various types of cancer. In head and neck squamous cell carcinoma (HNSCC), the clinical relevance of TATE has not been concluded yet because of the inconsistent results in different studies. In our study, we focus on the prognostic effects of TATE on HNSCC and how TATE can influence tumor behavior and tumor microenvironment. We first showed that in both the TCGA-HNSC cohort and our cohort of patients with HNSCC who had received curative surgery, TATE is correlated with worse overall survival. To investigate the underlying mechanism of how TATE leads to poor clinical outcomes, we showed that activated eosinophils produce a variety of cytokines and chemokines, and activated TATE-derived culture medium promotes tumor migration mainly through CCL2. We also showed that eosinophils are capable of inducing angiogenesis and that HNSCC samples enriched with TATE are highly correlated with tumor angiogenesis. Furthermore, HNSCC enriched with TATE had more aggressive pathological features, including regional lymph node metastasis, perineural invasion, lymphovascular invasion, and tumor growth. Lastly, we showed that HNSCC enriched with TATE is associated with immunosuppressive tumor microenvironment. Taken together, our results suggest that TATE promotes cancer metastasis and angiogenesis which results in a poor clinical outcomes in HNSCC.

Treatment outcomes of cetuximab-containing regimen in locoregional recurrent and distant metastatic head and neck squamous cell carcinoma.

BACKGROUND: Recurrent/ metastatic squamous cell carcinoma of head and neck (R/M SCCNH) is still a difficult-to-treat disease with poor clinical outcomes and limited treatment choices. In view of locoregional recurrent versus distant metastatic SCCHN, the therapeutic efficacy of cetuximab-containing regimen and relevant prognostic factors for these two groups may be different. Thus, the aim of this study was to explore the treatment outcomes of cetuximab-containing regimen in locoregional recurrent and distant metastatic SCCHN groups, and to identify clinical factors correlated with better survival outcomes. METHODS: From 2016 to 2020, patients with R/M SCCHN who received cetuximab-containing regimen in our institute were enrolled in this study. Clinical outcomes including overall survival (OS), progression-free survival (PFS), objective response rate (ORR) and disease control rate (DCR) were evaluated in both locoregional recurrence and distant metastasis groups. Exploratory analysis were conducted to investigate major clinical features associated with better outcomes. RESULTS: A total of 107 patients with locoregional recurrent SCCHN (N = 66) and distant metastatic SCCNH (N = 41) who received cetuximab-containing regimen were enrolled in this retrospective study. Patients with oral cavity cancer and patients with disease recurrence within 6 months after radiation therapy were significantly increased in locoregional recurrence group. The median OS (15.6 vs. 9.7 months, P = 0.004) and PFS (5.8 months vs. 4.2 months, P = 0.008) were longer in locoregional recurrence group than in distant metastasis group. In multivariate analysis of clinical features, locoregional recurrence was still an important risk factor associated with better OS (Hazzard ratio (HR) 0.64, p = 0.06) and PFS (HR 0.67, p = 0.075). In addition, a trend of favorable disease control rate (DCR; 62.5% vs. 45.0%, p = 0.056) was noted in locoregional recurrence group. In locoregional recurrence group, prior salvage surgery was associated with longer OS (HR = 0.24, P = 0.008) and PFS (HR = 0.30, P = 0.005). CONCLUSION: SCCHN with locoregional recurrence is associated with better disease control and survival outcomes comparing to distant metastatic SCCHN when treated with cetuximab-containing regimen. Salvage surgery for locoregional recurrence may further improves clinical outcome.

Efficacy of cetuximab-containing regimens in the treatment of recurrent/metastatic head and neck cancer after progression to immune checkpoint inhibitors.

BACKGROUND: The antiepidermal growth factor receptor (EGFR) monoclonal antibody cetuximab and immune checkpoint inhibitors (ICIs) are the current front-line treatment for recurrent and metastatic head and neck squamous cell carcinoma (R/M HNSCC). However, understanding of the efficacy of cetuximab-containing regimens in patients who fail ICI treatments is limited. In this study, we present the efficacy of cetuximab-based regimens in heavily pretreated R/M HNSCC patients after progression to ICIs. METHODS: This was a retrospective study that analyzed patients diagnosed with R/M HNSCC who progressed after ICIs and then received their first-time cetuximab-based regimens at Taipei Veterans General Hospital from January 2017 to December 2020. The response rate, overall survival, and progression-free survival were measured. RESULTS: A total of 28 patients were included in this study. Most patients had received pembrolizumab as an ICI. The median duration of cetuximab-based regimens prescribed was 4.5 months. The objective response rate (ORR) was 32.1% (95% confidence interval [CI], 17.9%-50.6%), and the disease control rate (DCR) was 53.6% (95% CI, 42.4%-76.4%). The median overall survival and median progression-free survival were 9.1 months (95% CI, 1.3-16.8) and 2.9 months (95% CI, 2.2-3.5), respectively. The incidence of cetuximab-related adverse events was reported as 39.2%. CONCLUSION: A cetuximab-based regimen is still an effective and tolerable treatment for R/M HNSCC after progression on ICIs. Future prospective studies are needed to identify better treatments for previously ICI-treated or heavily treated R/M HNSCC patients.

Combination of pembrolizumab and lenvatinib is a potential treatment option for heavily pretreated recurrent and metastatic head and neck cancer.

BACKGROUND: Immunotherapy has become the current standard of care for recurrent and metastatic head and neck squamous cell carcinoma (R/M HNSCC). One potential approach to improve immunotherapy efficacy is to combine pembrolizumab, an anti-PD-1 agent, with lenvatinib, a potent multikinase inhibitor. In this study, we presented our up-to-date experience with pembrolizumab/lenvatinib combination therapy in heavily pretreated R/M HNSCC. METHODS: Patients who had R/M HNSCC, were ineligible for curative treatment, progressed after at least two lines of systemic treatment and had received pembrolizumab/lenvatinib combination therapy were enrolled in this study. The primary endpoint was the objective response rate. The secondary endpoints included the disease control rate, overall survival, progression-free survival, and the duration of response. RESULTS: A total of 14 patients were enrolled in this study. All the patients had received at least two lines of systemic treatment and radiation therapy, and 71% of patients had failed previous anti-PD-1 treatment. The objective response rate of pembrolizumab/lenvatinib combination therapy was 28.6% (95% confidence interval [CI], 5.0%-52.2%). The disease control rate was 42.9% (95% CI, 17.0%-68.8%). The overall survival and progression-free survival were 6.2 months (95% CI, 2.9-9.6) and 4.6 months (95% CI, 0.05-0.9.2), respectively. Of those who had failed previous anti-PD-1 therapy, partial responses were observed in two patients. All the patients with partial responses were in the tumor proportion score <50 and combined positive score 1 to 19 groups. CONCLUSION: Our study provided up-to-date evidence that pembrolizumab/lenvatinib combination therapy achieved objective responses in both heavily pretreated and anti-PD-1 refractory R/M HNSCC patients. This study supported the use of pembrolizumab/lenvatinib combination therapy in R/M HNSCC patients without standard of care.

Effect of Primary Tumor Location on Postmetastasectomy Survival in Patients with Colorectal Cancer Liver Metastasis.

BACKGROUND: The effects of primary tumor location on colorectal liver metastasis (CRLM) and post-hepatic-metastasectomy overall survival (OS) are controversial. This study evaluated the difference in post-hepatic-metastasectomy OS among right-sided colon, left-sided colon, and rectal cancer groups. METHODS: In total, 381 patients who underwent curative-intent CRLM resection were enrolled. Patients were grouped based on the primary tumor location (right-sided, left-sided, and rectum). The Kaplan-Meier analysis and log-rank test were performed for survival analysis. The univariate and multivariate analyses of clinical and pathological factors were performed using the Cox proportional hazards model. RESULTS: Significant OS difference was noted among the three groups (log-rank, p = 0.014). The multivariate analysis revealed a 32% lower death risk in left-sided colon cancer compared with right-sided colon cancer (hazard ratio [HR] 0.68, p = 0.042), whereas no OS difference was noted between the rectal cancer and right-sided colon cancer groups. The left- versus right-sided OS advantage was noted only in the KRAS wild-type subgroup (HR 0.46, p = 0.002), and a rectal versus right-sided OS disadvantage was noted in the KRAS mutant subgroup (HR 1.78, p = 0.03). CONCLUSIONS: The CRLM post-hepatic-metastasectomy OS was superior in left-sided colon cancer than in right-sided colon cancer and was similar in rectal and right-sided colon cancer. The OS difference in different primary tumor locations is dependent on KRAS mutation status, with a decreased left- versus right-sided death risk noted only in KRAS wild-type colon cancer and an increased rectal versus right-sided death risk noted only in KRAS mutant colon cancer.

Comparison of reversal of rat pulmonary fibrosis of nintedanib, pirfenidone, and human umbilical mesenchymal stem cells from Wharton's jelly.

BACKGROUND: The present study compared the effects of antifibrotic medications, pirfenidone, and nintedanib, with transplantation of human umbilical mesenchymal stem cells (HUMSCs) in restoring rat pulmonary fibrosis (PF). METHODS: A stable animal model was established via an intratracheal injection of 5 mg bleomycin (BLM). One single transplantation of 2.5× 107 HUMSCs or initiation of daily oral nintedanib/pirfenidone administration was performed on day 21 following BLM damage. RESULTS: Pulmonary function examination revealed that BLM rats exhibited a significant decrease in blood oxygen saturation and an increase in respiratory rates. While no significant improvements were found in BLM rats receiving nintedanib or pirfenidone, those who transplanted with HUMSCs showed a statistical amelioration in blood oxygen saturation and significant alleviation in respiratory rates. Quantification results revealed that a significant reduction in alveolar space and marked increases in substantial cell infiltration and collagen deposition in the left lungs of BLM rats. No significant alteration was observed in BLM rats administered nintedanib or pirfenidone. However, BLM rats transplanted with HUMSCs had a significant recovery in alveolar space and noticeable decreases in cell infiltration and collagen deposition. The inflammatory cell numbers in the bronchoalveolar lavage was increased in the BLM group. While the rats treated with nintedanib or pirfenidone had a lower cell number than the BLM group, a higher cell number was found as compared with the Normal group. In rats transplanted with HUMSCs, the cell number did not differ from the Normal group. CONCLUSIONS: Transplantation of HUMSCs could effectively treat PF as opposed to the administration of anti-fibrotic drugs with nintedanib or pirfenidone with a significant better result in lung volume, pathological changes, lung function, and blood oxygen saturation.

Calcitonin Induces Bone Formation by Increasing Expression of Wnt10b in Osteoclasts in Ovariectomy-Induced Osteoporotic Rats.

Calcitonin is a small peptide hormone secreted from the parafollicular cells of the thyroid gland in response to an increase in serum calcium. The inhibition of osteoclastic resorption is the main mechanism by which calcitonin quickly decreases circulating calcium levels. Although calcitonin pharmacologically acts on osteoclasts to prevent bone resorption, the results of studies on genetically modified animals have shown that the physiological effect of calcitonin is in the inhibition of osteoblastic bone formation. Because the calcitonin receptor is only expressed in osteoclasts, the effect of calcitonin on osteoblasts maybe indirect and mediated via osteoclasts. Wnt ligands are involved in various aspects of skeletal biology, including bone remodeling and endochondral bone formation. Wnt10b has recently been recognized as a clastokine, and is potentially a therapeutic target for treating bone disorders. However, the extent to which Wnt signaling is involved in bone physiology and disease is not yet fully understood. We hypothesize that calcitonin indirectly increases osteoblastic bone formation by inducing Wnt10b expression in osteoclasts. Micro-CT analysis revealed reduced bone loss in calcitonin-treated ovariectomized rats. The serum of animals treated with calcitonin had decreased TRAP5b and CTX-1 but increased osteocalcin, P1NP, and Wnt10b. Immunohistochemistry staining showed that the level of Wnt10b in the femur was increased in calcitonin-treated groups as compared with control groups. Hematopoietic mononuclear cells were separated from rat femur and tibia bone marrow, and were induced into osteoclasts following treatment with M-CSF and RANKL. In these cells, immunoconfocal microscopy and Western blot analysis showed that calcitonin induced an increase in Wnt10b expression. In a culture of osteoblasts isolated from neonatal rat calvariae, the calcitonin-treated osteoclast supernatant showed an increase in mineralization, as indicated by ALP and alizarin red staining. Taken together, these results indicate that calcitonin induces bone formation by increasing the expression of Wnt10b in osteoclasts in ovariectomy-induced osteoporotic rats. The present study provides in-depth information about the effects of calcitonin on bone remodeling and will thus help in the development of future potential therapeutic strategies for postmenopausal osteoporosis.

Comparison between the therapeutic effects of differentiated and undifferentiated Wharton's jelly mesenchymal stem cells in rats with streptozotocin-induced diabetes.

BACKGROUND: Despite the availability of current therapies, including oral antidiabetic drugs and insulin, for controlling the symptoms caused by high blood glucose, it is difficult to cure diabetes mellitus, especially type 1 diabetes mellitus. AIM: Cell therapies using mesenchymal stem cells (MSCs) may be a promising option. However, the therapeutic mechanisms by which MSCs exert their effects, such as whether they can differentiate into insulin-producing cells (IPCs) before transplantation, are uncertain. METHODS: In this study, we used three types of differentiation media over 10 d to generate IPCs from human Wharton's jelly MSCs (hWJ-MSCs). We further transplanted the undifferentiated hWJ-MSCs and differentiated IPCs derived from them into the portal vein of rats with streptozotocin-induced diabetes, and recorded the physiological and pathological changes. RESULTS: Using fluorescent staining and C-peptide enzyme-linked immunoassay, we were able to successfully induce the differentiation of hWJ-MSCs into IPCs. Transplantation of both IPCs derived from hWJ-MSCs and undifferentiated hWJ-MSCs had the therapeutic effect of ameliorating blood glucose levels and improving intraperitoneal glucose tolerance tests. The transplanted IPCs homed to the pancreas and functionally survived for at least 8 wk after transplantation, whereas the undifferentiated hWJ-MSCs were able to improve the insulitis and ameliorate the serum inflammatory cytokine in streptozotocin-induced diabetic rats. CONCLUSION: Differentiated IPCs can significantly improve blood glucose levels in diabetic rats due to the continuous secretion of insulin by transplanted cells that survive in the islets of diabetic rats. Transplantation of undifferentiated hWJ-MSCs can significantly improve insulitis and re-balance the inflammatory condition in diabetic rats with only a slight improvement in blood glucose levels.

Novel immune-modulating drugs for advanced head and neck cancer.

BACKGROUND: Recently, two anti-PD-1 immune checkpoint inhibitors, pembrolizumab and nivolumab, have been approved by the US Food and Drug Administration for patients who fail on platinum-based chemotherapy. However, overall response and progression-free survival are still limited, and multiple novel agents are under development to fulfill this unmet clinical need. METHODS: Publications between 1992 and 2019 regarding the immunological/biological mechanisms and early phase clinical trial outcomes of immunomodulatory agents for head and neck cancer were described in this review article. RESULTS: Eleven immunomodulatory agents for advanced head and neck, including small molecules, antibodies, and therapeutic vaccines were described. Treatment responses were noted in nearly all 11 agents, as monotherapy or combination therapy. CONCLUSIONS: Potentials of the novel immunomodulatory agents to improve treatment efficacy of head and neck cancer and to maintain tolerable safety profile have been disclosed.

Reversal of bleomycin-induced rat pulmonary fibrosis by a xenograft of human umbilical mesenchymal stem cells from Wharton's jelly.

Pulmonary fibrosis (PF) is a progressive and irreversible condition with various causes, and no effective treatment has been found to rescue fibrotic lungs. Successful recovery from PF requires inhibiting inflammation, promoting collagen degradation and stimulating alveolar regeneration. Human umbilical mesenchymal stem cells (HUMSCs) not only regulate immune responses but also synthesize and release hyaluronan to improve lung regeneration. This study investigated the feasibility of HUMSC engraftment into rats with bleomycin (BLM)-induced PF to explore HUMSC therapeutic effects/outcomes. Methods: A unique BLM-induced left-lung-dominated PF animal model was established. Rats were transplanted with low-dose (5×106) or high-dose (2.5×107) HUMSCs on Day 21 after BLM injection. Combinations in co-culture of pulmonary macrophages, fibroblasts, HUMSCs treated with BLM and the same conditions on alveolar epithelia versus HUMSCs were evaluated. Results: Rats with high-dose HUMSC engraftment displayed significant recovery, including improved blood oxygen saturation levels and respiratory rates. High-dose HUMSC transplantation reversed alveolar injury, reduced cell infiltration and ameliorated collagen deposition. One month posttransplantation, HUMSCs in the rats' lungs remained viable and secreted cytokines without differentiating into alveolar or vascular epithelial cells. Moreover, HUMSCs decreased epithelial-mesenchymal transition in pulmonary inflammation, enhanced macrophage matrix-metallopeptidase-9 (MMP-9) expression for collagen degradation, and promoted toll-like receptor-4 (TLR-4) expression in the lung for alveolar regeneration. In coculture studies, HUMSCs elevated the MMP-9 level in pulmonary macrophages, released hyaluronan into the medium and stimulated the TLR-4 quantity in the alveolar epithelium. Principal Conclusions: Transplanted HUMSCs exhibit long-term viability in rat lungs and can effectively reverse rat PF.

Xenografting of human umbilical mesenchymal stem cells from Wharton's jelly ameliorates mouse spinocerebellar ataxia type 1.

BACKGROUND: Spinocerebellar ataxia type 1 (SCA1) is an autosomal dominant neurodegenerative disorder caused by the expansion of CAG repeats in ATXN1 gene resulting in an expansion of polyglutamine repeats in the ATXN1 protein. Unfortunately, there has yet been any effective treatment so far for SCA1. This study investigated the feasibility of transplanting human umbilical mesenchymal stem cells (HUMSCs) into transgenic SCA1 mice containing an expanded uninterrupted allele with 82 repeats in the ATXN1-coding region. METHODS: 106 human umbilical mesenchymal stem cells were transplanted into the cerebella at 1 month of age. RESULTS: HUMSCs displayed significant ameliorating effects in SCA1 mice in terms of motor behaviors in balance beam test and open field test as compared with the untransplanted SCA1 mice. HUMSCs transplantation effectively reduced the cerebellar atrophy, salvaged Purkinje cell death, and alleviated molecular layer shrinkage. Electrophysiological studies showed higher amplitudes of compound motor action potentials as indicated by increasing neuronal-muscular response strength to stimuli after stem cell transplantation. At 5 months after transplantation, HUMSCs scattering in the mice cerebella remained viable and secreted cytokines without differentiating into neuronal or glia cells. CONCLUSIONS: Our findings provide hope for a new therapeutic direction for the treatment of SCA1.

Elevation of ß-galactoside α2,6-sialyltransferase 1 in a fructoseresponsive manner promotes pancreatic cancer metastasis.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive type of pancreatic cancer with clinical characteristics of local invasion and early metastasis. Recent cohort studies indicate high fructose intake is associated with an increase in pancreatic cancer risk. However, the mechanisms by which fructose promotes pancreatic tumorigenesis remain unclear. Herein, Kras+/LSLG12D mice were crossed with Elas-CreER transgenic mice to determine whether fructose intake directly contributes to tumor formation. Orthotopic tumor-xenograft experiments were performed to determine whether fructose substitution enhances the metastatic potential of PDAC cells. The mechanisms underlying the effects of fructose were explored by RNAseq analysis in combination with high-performance anion exchange chromatography. Dietary fructose was initially found to promote the development of aggressive pancreatic cancer in mice conditionally expressing KrasG12D in the adult pancreas. We further revealed that fructose substitution enhanced the metastatic potential of human PDAC cell via selective outgrowth of aggressive ABCG2-positive subpopulations and elevating N-acetylmannosamine levels that upregulated ß-galactoside α2,6-sialyltransferase 1 (ST6Gal1), thereby promoting distant metastasis. Finally, we observed that PDAC patients expressing higher levels of ST6Gal1 and GLUT5 presented poorer prognosis compared to other groups. In conclusion, our findings have elucidated a crucial role of ST6Gal1 in regulating the invasiveness of PDACs in a fructose-responsive manner.

Comparisons of Differentiation Potential in Human Mesenchymal Stem Cells from Wharton's Jelly, Bone Marrow, and Pancreatic Tissues.

Background. Type 1 diabetes mellitus results from autoimmune destruction of ß-cells. Insulin-producing cells (IPCs) differentiated from mesenchymal stem cells (MSCs) in human tissues decrease blood glucose levels and improve survival in diabetic rats. We compared the differential ability and the curative effect of IPCs from three types of human tissue to determine the ideal source of cell therapy for diabetes. Methods. We induced MSCs from Wharton's jelly (WJ), bone marrow (BM), and surgically resected pancreatic tissue to differentiate into IPCs. The in vitro differential function of these IPCs was compared by insulin-to-DNA ratios and C-peptide levels after glucose challenge. In vivo curative effects of IPCs transplanted into diabetic rats were monitored by weekly blood glucose measurement. Results. WJ-MSCs showed better proliferation and differentiation potential than pancreatic MSCs and BM-MSCs. In vivo, WJ-IPCs significantly reduced blood glucose levels at first week after transplantation and maintained significant decrease till week 8. BM-IPCs reduced blood glucose levels at first week but gradually increased since week 3. In resected pancreas-IPCs group, blood glucose levels were significantly reduced till two weeks after transplantation and gradually increased since week 4. Conclusion. WJ-MSCs are the most promising stem cell source for ß-cell regeneration in diabetes treatment.

Undifferentiated Wharton's Jelly Mesenchymal Stem Cell Transplantation Induces Insulin-Producing Cell Differentiation and Suppression of T-Cell-Mediated Autoimmunity in Nonobese Diabetic Mice.

Type 1 diabetes mellitus is caused by T-cell-mediated autoimmune destruction of pancreatic ß-cells. Systemic administration of mesenchymal stem cells (MSCs) brings about their incorporation into a variety of tissues with immunosuppressive effects, resulting in regeneration of pancreatic islets. We previously showed that human MSCs isolated from Wharton's jelly (WJ-MSCs) represent a potential cell source to treat diabetes. However, the underlying mechanisms are unclear. The purpose of this study was to discern whether undifferentiated WJ-MSCs can differentiate into pancreatic insulin-producing cells (IPCs) and modify immunological responses in nonobese diabetic (NOD) mice. Undifferentiated WJ-MSCs underwent lentiviral transduction to express green fluorescent protein (GFP) and then were injected into the retro-orbital venous sinus of NOD mice. Seven days after transplantation, fluorescent islet-like cell clusters in the pancreas were apparent. WJ-MSC-GFP-treated NOD mice had significantly lower blood glucose and higher survival rates than saline-treated mice. Systemic and local levels of autoaggressive T-cells, including T helper 1 cells and IL-17-producing T-cells, were reduced, and regulatory T-cell levels were increased. Furthermore, anti-inflammatory cytokine levels were increased, and dendritic cells were decreased. At 23 days, higher human C-peptide and serum insulin levels and improved glucose tolerance were found. Additionally, WJ-MSCs-GFP differentiated into IPCs as shown by colocalization of human C-peptide and GFP in the pancreas. Significantly more intact islets and less severe insulitis were observed. In conclusion, undifferentiated WJ-MSCs can differentiate into IPCs in vivo with immunomodulatory effects and repair the destroyed islets in NOD mice.

IL-1ß-Induced Mesenchymal Stem Cell Migration Involves MLCK Activation via PKC Signaling.

Mesenchymal stem cells (MSCs) migrate via the bloodstream to sites of injury, possibly attracted by inflammatory cytokines. Although many cytokines can induce stem cell migration, the underlying mechanism is not fully understood. We found that tail vein-injected MSCs migrate to the pancreas in nonobese diabetic (NOD) mice. An ELISA assay revealed that hyperglycemic NOD mice have higher pancreatic levels of interleukin-1ß (IL-1ß) than normal NOD mice and that IL-1ß stimulates MSC migration in a Transwell assay and electric cell-substrate impedance sensing system. Microarray analysis showed that myosin light chain kinase (MLCK) is involved in IL-1ß-induced MSC migration, while Western blots showed that IL-1ß stimulates MLCK expression and activation and that MLCK-siRNA transfection reduces MSC migration. Kinase inhibitors, chromatin immunoprecipitation, and a knockdown study revealed that IL-1ß-induced MLCK expression is regulated by the PKCδ/NF-κB signaling pathway, and a kinase inhibitor study revealed that IL-1ß-induced MLCK activation occurs via the PKCα/MEK/ERK signaling pathway. These results show that IL-1ß released from the pancreas of hyperglycemic NOD mice induces MSC migration and that this is dependent on MLCK expression via the PKCδ/NF-κB pathway and on MLCK activation via the PKCα/MEK/ERK signaling cascade. This study increases our understanding of the mechanisms by which MSCs home to injury sites.

Intraportal injection of insulin-producing cells generated from human bone marrow mesenchymal stem cells decreases blood glucose level in diabetic rats.

We studied the process of trans-differentiation of human bone marrow mesenchymal stem cells (hBM-MSCs) into insulin-producing cells. Streptozotocin (STZ)-induced diabetic rat model was used to study the effect of portal vein transplantation of these insulin-producing cells on blood sugar levels. The BM-MSCs were differentiated into insulin-producing cells under defined conditions. Real-time PCR, immunocytochemistry and glucose challenge were used to evaluate in vitro differentiation. Flow cytometry showed that hBM-MSCs were strongly positive for CD44, CD105 and CD73 and negative for hematopoietic markers CD34, CD38 and CD45. Differentiated cells expressed C-peptide as well as ß-cells specific genes and hormones. Glucose stimulation increased C-peptide secretion in these cells. The insulin-producing, differentiated cells were transplanted into the portal vein of STZ-induced diabetic rats using a Port-A catheter. The insulin-producing cells were localized in the liver of the recipient rat and expressed human C-peptide. Blood glucose levels were reduced in diabetic rats transplanted with insulin-producing cells. We concluded that hBM-MSCs could be trans-differentiated into insulin-producing cells in vitro. Portal vein transplantation of insulin-producing cells alleviated hyperglycemia in diabetic rats.

Enhanced membrane-type 1 matrix metalloproteinase expression by hyaluronan oligosaccharides in breast cancer cells facilitates CD44 cleavage and tumor cell migration.

Hyaluronan (HA), a component of the extracellular matrix, plays an important role in cell-cell adhesion and cell migration. Membrane type 1-matrix metalloproteinase (MT1­MMP) is often expressed in invasive cancer cells. CD44, a transmembrane receptor for HA, is implicated in various adhesion-dependent cellular processes including cell migration, tumor cell metastasis and invasion. Previous studies have shown that CD44 is highly expressed in cancer cells and may be proteolytically cleaved at the ectodomain by MT1-MMP; this process of inducing CD44 cleavage plays a critical role in cancer cell migration. We hypothesized that HA modulates MT1-MMP expression to facilitate breast cancer cell migration. Flow cytometry, real-time PCR, western blotting and immunofluorescence staining were used to quantify HA-induced MT1-MMP expression in breast cancer cells. In order to validate the relevance of cell migration and HA-induced MT1-MMP, we analyzed the cell migration via matrigel-coated transwell. We found that after HA oligosaccharide (6.5 kDA) stimulation, MT1-MMP expression in the membrane of breast cancer cells was increased. In response to HA oligosaccharide stimulation, significant upregulation of MT1-MMP mRNA occurred. Our data also provide evidence that HA oligosaccharide enhances MT1-MMP; the elevated expression of MT1-MMP confers enhanced CD44 cleavage and cell migration. In conclusion, we have identified a new function of HA in the induction of MT1-MMP expression in breast cancer cell lines and CD44 cleavage to increase cell migration during the invasion process. The HA oligosaccharide-induced MT1-MMP expression in breast cancer cells may be a critical step in the formation of metastatic colonies.