Potential of Z-100, extracted from Mycobacterium tuberculosis strain Aoyama B, as a hot tumor inducer.

The tumor microenvironment is one of the most important factors determining the efficacy of cancer immunotherapy. In particular, variability in efficacy has been linked to whether tumors are hot or cold, with hot tumors exhibiting greater T cell infiltration and responding better to immunotherapy. Z-100 extracted from Mycobacterium tuberculosis Aoyama B strain has been reported to increase cytokine production from immune cells. In this study, we examined its effect on the tumor microenvironment and its potential as a hot tumor inducer. The antitumor effect of Z-100 was confirmed in a mouse oral squamous cell carcinoma (Sq-1979) tumor model by starting administration before tumor injection. Treated tumors were collected to identify infiltrating CD8+ T cells. The antitumor effects of Z-100 were additionally examined in mice treated with anti-CD8 antibody and in IL-12p40 knockout (KO) mice. We found that Z-100 had strong antitumor effects and increased the proportion of CD8+ T cells in tumors. Moreover, the CD8+ T cells infiltrating tumors were identified as effector memory CD8+ T cells. Furthermore, the antitumor effects of Z-100 were abolished in mice treated with an anti-CD8 antibody and in IL-12p40 KO mice. Thus, Z-100 induces its antitumor effects by increasing tumor-infiltrating CD8+ T cells, suggesting that Z-100 may be a useful cancer therapy by acting as a hot tumor inducer.

Effects of the chelating agent DTPA on naturally accumulating metals in the body.

Diethylenetriaminepentaacetate (DTPA) is the most widely used chelating agent for Pu and Am. Volunteers were assigned to receive intravenous injections or aerosol inhalations of 1 g of DTPA on days 1-4; volunteers received once daily injections of CaDTPA or ZnDTPA, CaDTPA inhalation as an aerosol, or CaDTPA injection on day 1 and ZnDTPA on days 2-4. CaDTPA injection or inhalation increased the excretion rates of Zn in urine with concomitantly reduced levels of serum Zn. Injection of CaDTPA reduced activities of serum alkaline phosphatase (AP) in parallel with the kinetics of Zn, whereas CaDTPA and ZnDTPA injection reduced activities of lactate dehydrogenase (LDH), and reduced activities of creatinine kinase (CK) were observed upon CaDTPA injection and its inhalation. Intravenous administration of CaDTPA and ZnDTPA enhanced excretion rates of Mn in urine, whereas transient reduction of Mn levels in serum was detected only via CaDTPA injection. Both CaDTPA and ZnDTPA transiently reduced levels of Mg in serum without affecting the excretion rates. On the other hand, both DTPAs increased excretion rates of toxic metals such as Pb and Cd, and CaDTPA also increased the rates of Hg. These results suggest that DTPA, and especially CaDTPA, removes essential metals and that the activities of these metalloenzymes are good indicators for the imbalance of essential metals during the DTPA administration. Our results also show that CaDTPA injection is more potent for removing these metals than ZnDTPA and inhalation of CaDTPA, and DTPA may be useful for the treatment of acute heavy metal poisoning with Pb, Cd, or Hg.

In Situ Monitoring of Surface Reactions during Atomic Layer Etching of Silicon Nitride Using Hydrogen Plasma and Fluorine Radicals.

The atomic layer etching (ALE) of silicon nitride (SiN) via a hydrogen plasma followed by exposure to fluorine radicals was investigated by using in situ spectroscopic ellipsometry and attenuated total reflectance Fourier transform infrared (FTIR) spectroscopy to examine the surface reactions and etching mechanism. FTIR spectra of the surface following exposure to the hydrogen plasma showed an increase in the concentration of Si-H and N-H bonds, although the N-H bond concentration plateaued more quickly. In contrast, during fluorine radical exposure, the Si-H bond concentration decreased more rapidly. Secondary ion mass spectrometry demonstrated that the nitrogen atom concentration was decreased to a depth of 4 nm from the surface after the hydrogen plasma treatment and indicated a structure consisting of N-H rich, Si-H rich, and mixed layers. This indicated that Si-H bonds were primarily present near the surface, while N-H bonds were mainly located deeper into the film. The formations of the N-H and Si-H rich layers are important phenomena associated with modification by hydrogen plasma and fluorine radical etching, respectively.

Circulating nano-particulate TLR9 agonist scouts out tumor microenvironment to release immunogenic dead tumor cells.

Recent evidence suggest that a ß-glucan derived from mushroom Schizophyllan(SPG) complexed with a humanized TLR9 agonistic CpG DNA, K3 (K3-SPG) is a promising vaccine adjuvant that induces robust CD8 T cell responses to co-administered antigen. However, it has not been investigated whether K3-SPG alone can act as an anti-cancer immunotherapeutic agent or not. Here, we demonstrate that intravenous injection of K3-SPG, but not CpG alone, is accumulated in the tumor microenvironment and triggered immunogenic cell death (ICD) of tumor cells by local induction of type-I interferon (IFN) as well as IL-12. Resultant innate immune activation as well as subsequent tumor-specific CD8 T cell responses were contributed the tumor growth suppression. This anti-tumor effect of K3-SPG monotherapy was also confirmed by using various tumor models including pancreatic cancer peritoneal dissemination model. Taken together, nano-particulate TLR9 agonist injected intravenously can scout out tumor microenvironment to provoke local innate immune activation and release dead tumor cells into circulation that may induce broader and protective tumor antigen-specific CD8 T cells.

Impaired smooth-pursuit in Parkinson's disease: normal cue-information memory, but dysfunction of extra-retinal mechanisms for pursuit preparation and execution.

While retinal image motion is the primary input for smooth-pursuit, its efficiency depends on cognitive processes including prediction. Reports are conflicting on impaired prediction during pursuit in Parkinson's disease. By separating two major components of prediction (image motion direction memory and movement preparation) using a memory-based pursuit task, and by comparing tracking eye movements with those during a simple ramp-pursuit task that did not require visual memory, we examined smooth-pursuit in 25 patients with Parkinson's disease and compared the results with 14 age-matched controls. In the memory-based pursuit task, cue 1 indicated visual motion direction, whereas cue 2 instructed the subjects to prepare to pursue or not to pursue. Based on the cue-information memory, subjects were asked to pursue the correct spot from two oppositely moving spots or not to pursue. In 24/25 patients, the cue-information memory was normal, but movement preparation and execution were impaired. Specifically, unlike controls, most of the patients (18/24 = 75%) lacked initial pursuit during the memory task and started tracking the correct spot by saccades. Conversely, during simple ramp-pursuit, most patients (83%) exhibited initial pursuit. Popping-out of the correct spot motion during memory-based pursuit was ineffective for enhancing initial pursuit. The results were similar irrespective of levodopa/dopamine agonist medication. Our results indicate that the extra-retinal mechanisms of most patients are dysfunctional in initiating memory-based (not simple ramp) pursuit. A dysfunctional pursuit loop between frontal eye fields (FEF) and basal ganglia may contribute to the impairment of extra-retinal mechanisms, resulting in deficient pursuit commands from the FEF to brainstem.

Z-100, an immunomodulatory extract of Mycobacterium tuberculosis strain Aoyama B, prevents spontaneous lymphatic metastasis of B16-BL6 melanoma.

Lymphatic metastasis is common in advanced-stage carcinoma and is associated with a poor prognosis. However, few effective treatments to inhibit it are available. Z-100 is an immunomodulatory extract of Mycobacterium tuberculosis strain Aoyama B that contains polysaccharides such as arabinomannan and mannan. Here, we investigated the inhibitory effect of Z-100 on spontaneous lymphatic metastasis. C57BL/6N mice injected subcutaneously with B16-BL6 melanoma cells in the right hind footpad were administered Z-100 subcutaneously in the right inguinal region on a daily basis. On day twenty-one after the injection, the right inguinal lymph nodes were excised, and the extent of metastasis, the number of immune cells, and the amount of granzyme B protein in the lymph nodes were examined. We also investigated the combined effect of Z-100 and irradiation in this model. Results showed that Z-100 reduced number of animals with metastasis, with respective metastasis rates of 85.7%, 42.9%, 7.1% and 0.0% in saline, 0.1 mg/kg Z-100, 1 mg/kg Z-100 and 10 mg/kg Z-100 group. Further, mice that had been given Z-100 were found to have more immune cells and granzyme B protein in the lymph nodes than control mice. The combination of low dose Z-100 and irradiation also inhibited spontaneous lymph node metastases. These findings suggest that Z-100 may be beneficial in preventing lymphatic metastasis by enhancing the immune response.

[Cerebellum and eye movement control -- neuronal mechanisms of memory-based smooth-pursuit and their early clinical application].

Recent studies implicate the cerebellum in cognitive functions in addition to its well-established roles in motor control and learning. Using a memory-based smooth-pursuit task that separates visual working memory from motor preparation and execution, monkeys were trained to pursue (i.e., go) or not pursue (i.e., no-go), a cued direction, based on the working memory of visual motion-direction and a go/no-go instruction. Task-related neuronal activity was examined in cerebral and cerebellar major smooth-pursuit pathways. Different cerebral and cerebellar areas carried distinctly different signals during memory-based smooth-pursuit. In the cerebellum, prediction-related signals (visual working memory, pursuit selection and movement preparation) were represented in the vermal lobules VI-VII and caudal fastigial nucleus, whereas the floccular region (flocculus and ventral paraflocculus) contained predominantly execution-related signals. This task was applied to patients with cerebellar degeneration and idiopathic Parkinson's disease (PD). None of the PD patients tested exhibited impaired working memory of motion-direction and/or go/no-go selection, but they did show task-specific difficulty in generating an initial smooth-pursuit component, suggesting difficulty in smooth-pursuit preparation. In contrast, most cerebellar patients exhibited impaired visual working memory in addition to difficulty in preparing for and executing smooth-pursuit. These results suggest different roles for the basal ganglia and cerebellum in smooth-pursuit planning.

CCK-2/gastrin receptor signaling pathway is significant for gemcitabine-induced gene expression of VEGF in pancreatic carcinoma cells.

AIMS: As activation and overexpression of the cholecystokinin-2 (CCK-2)/gastrin receptor can lead to carcinogenesis, it has been explored as a therapeutic target in pancreatic cancer. We demonstrated that Z-360, a CCK-2/gastrin receptor antagonist, combined with gemcitabine prolonged survival and reduced gemcitabine-induced vascular endothelial growth factor (VEGF) expression in a pancreatic carcinoma orthotopic xenograft mouse. In this study, we investigated the role of the CCK-2/gastrin signaling pathway on gemcitabine-induced VEGF expression in PANC-1 human pancreatic carcinoma cells. MAIN METHODS: In PANC-1 cells treated with Z-360, anti-gastrin IgG or kinase inhibitors, the gene expression levels were analyzed by quantitative real-time RT-PCR, and the protein levels of Akt and phosphorylated Akt (p-Akt) in cellular extracts were measured by ELISA. KEY FINDINGS: Gemcitabine-induced expression of VEGF and hypoxia-inducible factor-1 alpha (HIF-1 alpha) were suppressed by the treatment with an anti-gastrin antibody. In addition, VEGF and HIF-1 alpha gene expression was inhibited by treatment with an inhibitor of phosphatidylinositol 3-kinase (PI3K), which is involved in the downstream signaling pathway of the CCK-2/gastrin receptor, and was also suppressed by treatment with Z-360. Moreover, although Akt phosphorylation was increased by treatment with gemcitabine, this elevation was partially, but significantly, inhibited by an exposure of Z-360. SIGNIFICANCE: Gemcitabine might induce gene expression of VEGF via the PI3K/Akt signaling pathway in the downstream of the CCK-2/gastrin receptor. The suppression of the CCK-2/gastrin signaling pathway by treatment with Z-360 could be a useful approach for potentiating prolonged survival of pancreatic cancer patients receiving gemcitabine therapy.

Z-360, a novel therapeutic agent for pancreatic cancer, prevents up-regulation of ephrin B1 gene expression and phosphorylation of NR2B via suppression of interleukin-1 ß production in a cancer-induced pain model in mice.

BACKGROUND: Z-360 is an orally active cholecystokinin-2 (CCK2)/gastrin receptor antagonist currently under development as a therapeutic drug for pancreatic cancer. It was previously reported that Z-360 treatment in combination with gemcitabine prolonged the survival period in a lethal pancreatic cancer xenograft model in mice. In a phase Ib/IIa clinical study, Z-360 treatment displayed a trend of reduced pain in patients with advanced pancreatic cancer in combination with gemcitabine including analgesics such as opioids. Here, we investigated the mechanism of analgesic action of Z-360 in a severe cancer-induced pain model in mice, which is considered to be opioid-resistant, by examining ephrin B1 gene expression, N-methyl-D-aspartate receptor NR2B subunit phosphorylation, and interleukin-1ß (IL-1ß) production. RESULTS: In a mouse model of cancer-induced pain, ephrin B1 gene expression in dorsal root ganglia (DRGs) and the phosphorylation of NR2B in the spinal cord were induced. Z-360 treatment inhibited both ephrin B1 gene expression and the phosphorylation of NR2B. In addition, IL-1ß production increased in the cancer-inoculated hind paw of mice, but could be suppressed by treatment with Z-360. Moreover, we observed that the CCK1 receptor antagonist devazepide similarly suppressed up-regulation of ephrin B1 gene expression and IL-1ß production, and that the intraperitoneal injection of sulfated CCK-8 induced the production of IL-1ß in the cancer-inoculated region. CONCLUSIONS: We have identified a novel pain cascade, in which IL-1ß production in cancer-inoculated regions induces ephrin B1 gene expression in DRGs and then ephrin B1 enhances the tyrosine phosphorylation of NR2B via Eph B receptor in the spinal cord. Notably, Z-360 relieves cancer-induced pain by preventing this pain cascade through the suppression of IL-1ß production, likely via the blockade of CCK1 receptor. The pre-clinical results presented here support the analgesic action of Z-360 in pancreatic cancer patients with severe, opioid-resistant pain. Pre-clinical and clinical results have demonstrated that Z-360 combined with gemcitabine represents a promising pancreatic cancer therapy approach with characteristic analgesic effects in addition to the prolongation of survival.

Z-360, a novel cholecystokinin-2/gastrin receptor antagonist, inhibits gemcitabine-induced expression of the vascular endothelial growth factor gene in human pancreatic cancer cells.

Z-360 is a novel cholecystokinin (CCK)-2/gastrin receptor antagonist that is being developed for the treatment of pancreatic adenocarcinoma in combination with gemcitabine. A previous study shows that the co-administration of Z-360 with gemcitabine significantly prolonged the survival of mice with orthotopically implanted human pancreatic adenocarcinoma cell lines. To clarify the therapeutic effects of Z-360 in combined with gemcitabine, we analyzed gene expression. When gemcitabine was administered, CCK-2/gastrin receptor expression was induced in an orthotropic xenograft model; the result indicating that Z-360 could act on gemcitabine-sensitive cells. Both in vitro and in vivo studies showed that gemcitabine increased the expression of vascular endothelial growth factor A (VEGFA), a prognostic factor for survival in pancreatic cancer, while Z-360 suppressed this induction of VEGFA gene expression. These results help to explain how Z-360 prolongs survival when used in combination with gemcitabine.

Characterization of the ATP-dependent sphingosine 1-phosphate transporter in rat erythrocytes.

Sphingosine 1-phosphate (S1P) is a bioactive lipid signal transmitter present in blood. Blood plasma S1P is supplied from erythrocytes and plays an important role in lymphocyte egress from lymphoid organs. However, the S1P export mechanism from erythrocytes to blood plasma is not well defined. To elucidate the mechanism of S1P export from erythrocytes, we performed the enzymatic characterization of S1P transporter in rat erythrocytes. Rat erythrocytes constitutively released S1P without any stimulus. The S1P release was reduced by an ABCA1 transporter inhibitor, glyburide, but not by a multidrug resistance-associated protein inhibitor, MK571, or a multidrug resistance protein inhibitor, cyclosporine A. Furthermore, we measured S1P transport activity using rat erythrocyte inside-out membrane vesicles (IOVs). Although the effective S1P transport into IOVs was observed in the presence of ATP, this activity was also supported by dATP and adenosine 5'-(beta,gamma-imido)triphosphate. The rate of S1P transport increased depending on S1P concentration, with an apparent K(m) value of 21 microm. Two phosphorylated sphingolipids, dihydrosphingosine 1-phosphate and ceramide 1-phosphate, did not inhibit S1P transport. Similar to the intact erythrocytes, the uptake of S1P into IOVs was inhibited by glyburide and vanadate but not by the other ABC transporter inhibitors. These results suggest that S1P is exported from the erythrocytes by a novel ATP-dependent transporter.

Effects of stroke-induced damage to swallow-related areas in the brain on swallowing mechanics of elderly patients.

AIM: Our objective was to determine the relationship between defective swallowing mechanics and the location of brain lesions in stroke patients. METHODS: We evaluated swallowing mechanics in 37 stroke patients and 10 age-matched control subjects by videofluoroscopy. Subjects were asked to swallow 10 successive 1.0-mL and three successive 2.5-mL boluses of barium suspension at intervals of approximately 15-30 s. We measured oral transit time, pharyngeal delay time and pharyngeal transit time. RESULTS: Patients could be divided into two groups based on the pharyngeal delay time for a 1.0-mL bolus swallow. One group showed little variation during successive swallowing tests, similar to the control group. In the other group pharyngeal delay times varied during successive trials often tending to increase with successive swallows. Magnetic resonance imaging studies of the brain revealed infarcts or hemorrhages in swallow-related areas in the latter group, while in the former group lesions were localized to areas unrelated to swallowing. CONCLUSION: Damage to swallow-related areas may reduce their sensitivity to incoming signals from the oral cavity thereby impairing preparations to generate motor command signals and compromising their ability to send sufficient voluntary descending command signals to activate the swallowing central pattern generator located in the medulla. This deficiency becomes more evident with successive swallows and manifests as impaired swallowing mechanics.

Age-related urinary excretion of BK polyomavirus by nonimmunocompromised individuals.

Two polyomaviruses, BK virus (BKV) and JC virus (JCV), are ubiquitous in the human population, generally infecting children asymptomatically and then persisting in renal tissue. It is generally thought that reactivation leads to productive infection for both viruses, with progeny shed in the urine. Several studies have shown that the rate of JC viruria increases with the age of the host, but a systematic approach to examine the shedding of BKV has not been developed. To elucidate the relationship between BK viruria and host age, we obtained urine from donors (healthy volunteers or nonimmunocompromised patients) who were divided into nine age groups, each containing 50 members. A high-sensitivity PCR was used to detect BKV and JCV DNA from urinary samples, and the specificity of amplification was confirmed by sequencing or restriction analysis of the amplified fragments. The rate of BK viruria was relatively low in subjects aged <30 years but gradually increased with age in subjects aged > or =30 years. However, BK viruria was less frequent than JC viruria in adults. The detected BKV isolates were classified into subtypes, and detection rates for individual subtypes were compared among age groups; this analysis showed that viruria of subtypes I (the most prevalent subtype) and IV (the second most prevalent subtype) occurred more frequently in older subjects. Therefore, our results reveal new aspects of BK viruria in nonimmunocompromised individuals.

Posterior-anterior body weight shift during stance period studied by measuring sole-floor reaction forces during healthy and hemiplegic human walking.

Posterior-anterior body weight shift during stance phase of human overground locomotion was investigated by recording sole-floor reaction force from five anatomically discrete points with strain gauge transducers of 14 mm diameter attached firmly to the sole of bare foot. At first the subject was asked to walk straight on the laboratory floor at his/her preferred velocity. Then the subject was asked to walk curved path of about 1m radius. For kicking off the body at the end of stance phase, sole-floor reaction force from 3rd metatarsal was stronger than 1st metatarsal or 5th metatarsal during the straight walking, thus body weight shift is represented from heel to 3rd metatarsal line. When walking along a curved path, two types of strategies were recognized; a group of subjects walked leaning to inner leading foot during stance period as judged by stronger forces recorded from 5th metatarsal combined with stronger force from 1st metatarsal of outer trailing foot. Another group of subjects showed almost the same patterns either in the straight and curved walking, suggesting the subjects changed direction of the foot during the immediately previous swing phase to the tangent direction of the curve and placed the foot without leaning the body weight to either direction. Hemiplegic patients showed strikingly different distribution of sole-floor reaction forces from the five points; strongest forces were recorded from 3rd and 5th metatarsals combined with reduced reaction force from heel, therefore characteristic y-vector patterns were observed.

Sphingosine 1-phosphate is released from the cytosol of rat platelets in a carrier-mediated manner.

Sphingosine 1-phosphate (S1P) is accumulated in platelets and released on stimulation by thrombin or Ca(2+). Thrombin-stimulated S1P release was inhibited by staurosporin, whereas Ca(2+)-stimulated release was not. When the platelet plasma membrane was permeabilized with streptolysin O (SLO), S1P leaked out with cytosol markers, whereas granular markers remained in the platelets. The SLO-induced S1P leakage required BSA, probably for solubilization of S1P in the medium. These results indicate that S1P is localized in the inner leaflet of the plasma membrane and that its release is a carrier-mediated process. We also used alpha-toxin (ATX), which makes smaller pores in the plasma membrane than SLO and depletes cytosolic ATP without BSA-dependent S1P leakage. The addition of ATP drove S1P release from ATX platelets. The ATP-driven S1P release from ATX platelets was greatly enhanced by thrombin. An ATP binding cassette transporter inhibitor, glyburide, prevents ATP- and thrombin-induced S1P release from platelets. Ca(2+) also stimulated S1P release from ATX platelets without ATP, whereas the Ca(2+)-induced release was not inhibited by glyburide. Our results indicate that two independent S1P release systems might exist in the platelet plasma membrane, an ATP-dependent system stimulated by thrombin and an ATP-independent system stimulated by Ca(2+).

Treadmill walking and overground walking of human subjects compared by recording sole-floor reaction force.

In order to clarify differences of treadmill from overground locomotion, experiments were carried out on 10 volunteers (five males and five females). Sole-floor reaction force was recorded from five anatomically discrete points with strain gauge transducers of 14 mm diameter attached firmly to the sole of bare-foot. At first the subject was asked to walk on the laboratory floor at his/her preferred velocity. After the average velocity was obtained, the subject was asked to walk on the treadmill at the same velocity of average overground walking. Stance period at treadmill walking shortened to 93.3% (P < 0.01) of the value at overground walking. Coefficient of variation of stance period was significantly smaller at the treadmill walking than at overground walking. Strain gauge-floor contact times were shorter in the treadmill walking; heel 81.2%, first metatarsal 93.5%, third metatarsal 93.6%, fifth metatarsal 90.6% and at great toe 93.2% of overground locomotion. Cadence during treadmill locomotion was significantly larger than overground walking (106.6%, P < 0.05). These results show that when subjects walk on the treadmill and on laboratory floor at the identical speed, stance period shortened by 6.7% while cadence increased by 6.6% on the treadmill.

[A case of non-curatively resected scirrhous gastric cancer successfully treated over 2 years with weekly administration of paclitaxel].

We report a patient with far-advanced gastric cancer treated by weekly administration of paclitaxel (TXL) over 2 years. The patient was a 66-year-old female with peritoneal metastasis and remarkable lymph node metastasis of scirrhous gastric cancer. She underwent a non-curative resection with total gastrectomy and splenectomy in May 2002. Postoperative chemotherapy with TS-1 (80 mg/body) was performed. Due to grade 4 neutropenia and grade 2 anorexia, this treatment could not be continued. Three months after surgery, the tumor marker (CA19-9) had elevated to an abnormal level. Alternatively, TXL was administered at a weekly dose of 70 mg/m2 for 3 weeks followed by 6 weeks rest from September 2002. The tumor marker (CA19-9) gradually decreased to the normal level. Because of the long rest interval, 10 courses of treatment could be continued, and the patient has been alive over 2 years with the cancer controlled. There have been few effective chemotherapies for gastric cancer with peritoneal metastasis. Weekly paclitaxel therapy is considered to be effective for the treatment of advanced scirrhous gastric cancer with peritoneal metastasis.

Analysis of human locomotion by recording sole-floor reaction forces from anatomically discrete points.

Sole-floor reaction forces were recorded from five anatomically discrete points to analyze characteristics of human locomotion. Strain gauge of 14 mm diameter were firmly attached to the sole of bare-foot for recording force changes from the following five points: (1) medial process of calcaneus, (2) head of 1st metatarsal, (3) head of 3rd metatarsal, (4) head of 5th metatarsal and (5) great toe. Fifteen healthy adults were asked to walk at 2, 4, 6 and 8 km/h and to run at 8 km/h on the treadmill. Sole-floor reaction forces from 1st to 5th metatarsals show reciprocal changes during stance phase, while force from 1st metatarsal is strong 5th metatarsal shows weak reaction and vice versa. This phenomenon may be an expression of locomotor program to maintain vertical stability of the body during stance phase. There was a linear relation between walking speeds and sum of force from the five points, although sum of forces from three metatarsals did not change significantly during the walking speeds, indicating mainly calcaneus and great toe contribute to increasing walking speed. During running the sum of force from the three metatarsals increased sharply, joining the other two points to increase thrust.