The epidermal growth factor receptor (EGFR)/RAS/RAF/MEK/MAPK pathway plays a crucial role in the carcinogenesis, invasion and metastasis of colorectal cancer (CRC). However, its role in the prognosis and prediction of relapse in patients with stage III CRC after adjuvant chemotherapy remains controversial. In the present study, the clinicopathological features of 173 patients with stage III CRC who underwent radical resection and adjuvant chemotherapy with the fluoropyrimidine/folinic acid, and oxaliplatin (FOLFOX) regimen, and their prognostic values of EGFR expression were retrospectively analyzed. By conducting an in vitro CRC cell line study through the knockdown of EGFR expression, we analyzed cell proliferation, colony formation and migration. Positive EGFR expression and an abnormal postoperative serum carcinoembryonic antigen (CEA) level were found to be significant independent negative predictive factors for postoperative relapse. Furthermore, positive EGFR expression was a significant independent negative prognostic factor for disease-free survival (DFS) and overall survival (OS). Additionally, an in vitro cell line study showed that the knockdown of EGFR expression significantly reduced CRC cell proliferation, colony formation and migration. The results of in vitro and in vivo experiments demonstrated that EGFR expression had a prognostic value for OS and DFS, as well as predictive roles for postoperative relapse, in patients with stage III CRC. By analyzing both EGFR expression and the postoperative CEA, the patients with stage III CRC who were at a high risk of postoperative relapse, or mortality following adjuvant chemotherapy could be identified. In short, CRC cells with EGFR expression would exhibit a highly malignant behavior.

Lack of mechanical stress may result in osteoporosis; however, the underlying mechanisms of disuse osteoporosis remain unclear. It has been indicated that mechanical loading causes extracellular glutamate accumulation in osteoblasts. We hypothesized that the glutamate receptor mediation on bone cells might also be involved in mechanically stimulated osteogenesis. In this study, we investigated the changes of bone formation and the expressions of osteogenic genes and N-methyl D-aspartate (NMDA) receptors, the major glutamate receptors, in disused bones. Rat modeled disuse osteopenia in hind limbs was induced by a 3-week tail suspension in Sprague-Dawley rats. Bone mineral density and trabecular bone volume of distal femurs were measured to verify the osteopenia of disused bones. The mRNA expressions of cbfa1/Runx2, type I collagen, alkaline phosphatase (ALP) and osteocalcin (OC) in bones were measured as osteogenic markers. The influences of mechanical unloading on the expressions of NMDA receptors (NR1 and NR2D) in bones were also examined. The effects of NMDA mediation on osteogenesis were tested by a treatment of MK-801, a non-competitive NMDA receptor antagonist, in cultured osteoblasts and bone marrow stroma cells. Our result showed that mRNA expressions of cbfa1/Runx2, type I collagen, ALP and OC were significantly decreased in disused bones. The mRNA and protein expressions of NR1 and NR2D were significantly decreased in disused bones; furthermore, immunolocalization of both receptors showed decreases in osteoblasts, but not in osteoclasts. The results from the in vitro study showed that MK-801 inhibited mRNA expression of cbfa1/Runx2 in bone marrow stroma cells and also inhibited those of collagen type I, ALP and OC of osteoblasts in a dose-dependent manner. These results suggest that NMDA receptor mediation may play an important role in transmitting mechanical loading in bones, and decreases of the expressions of NMDA receptors in disused bones, especially in osteoblasts, may contribute to the decrease of osteogenesis.

Colorectal cancer (CRC) is the third most common cancer worldwide. The incidence and mortality rates of CRC are significantly higher in Taiwan than in other developed countries. Genes involved in CRC tumorigenesis differ depending on whether the tumor occurs on the left or right side of the colon, and genomic analysis is a keystone in the study and treatment of CRC subtypes. However, few studies have focused on the genetic landscape of Taiwanese patients with CRC. This study comprehensively analyzed the genomes of 141 Taiwanese patients with CRC through whole-exome sequencing. Significant genomic differences related to the site of CRC development were observed. Blood metabolomic profiling and polygenic risk score analysis were performed to identify potential biomarkers for the early identification and prevention of CRC in the Taiwanese population. Our findings provide vital clues for establishing population-specific treatments and health policies for CRC prevention in Taiwan.

Studies have demonstrated that metformin has antitumor effects in addition to therapeutic effects on hyperglycemia; however, few studies have explored the effects of metformin in chemotherapy. Therefore, we hypothesized that the administration of metformin would enhance the therapeutic effects of 5-fluorouracil and oxaliplatin (FuOx) to inhibit the growth of colorectal cancer (CRC) cells in vitro and in vivo. The results of our in vitro experiments demonstrated that metformin significantly increased the effects of FuOx with respect to cell proliferation (p < 0.05), colony formation (p < 0.05), and migration (p < 0.01) and induced cell cycle arrest in the G0/G1 phase in HT29 cells and the S phase in SW480 and SW620 cells (p < 0.05). Flow cytometry analysis revealed that metformin combined with FuOx induced late apoptosis (p < 0.05) by mediating mitochondria-related Mcl-1 and Bim protein expression. Furthermore, in vivo, metformin combined with FuOx more notably reduced tumor volume than FuOx or metformin alone did in BALB/c mice (p < 0.05). These findings demonstrate that metformin may act as an adjunctive agent to enhance the chemosensitivity of CRC cells to FuOx. However, further clinical trials are warranted to validate the clinical implications of the findings.

There is now increasing evidence from the experimental and clinical setting that therapeutic hypercapnia from intentionally inspired carbon dioxide (CO(2)) or lower tidal volume might be a beneficial adjunct to the strategies of mechanical ventilation in critical illness. Although previous reports indicate that CO(2) exerts a beneficial effect in the lungs, the pulmonary vascular response to hypercapnia under various conditions remains to be clarified. The purpose of the present study is to characterize the pulmonary vascular response to CO(2) under the different conditions of pulmonary hypertension secondary to increased pulmonary blood flow and secondary to hypoxic pulmonary vasoconstriction. Isolated rat lung (n = 32) was used to study (1) the vasoactive action of 5% CO(2) in either N(2) (hypoxic-hypercapnia) or air (normoxic-hypercapnia) at different pulmonary arterial pressure levels induced by graded speed of perfusion flow and (2) the role of nitric oxide (NO) in mediating the pulmonary vascular response to hypercapnia, hypoxia, and flow-associated pulmonary hypertension. The results indicated that inhaled CO(2) reversed pulmonary hypertension induced by hypoxia but not by flow alteration. Endogenous NO attenuates hypoxic pulmonary vasoconstriction but does not augment the CO(2)-induced vasodilatation. Acute change in blood flow does not alter the endogenous NO production.

Sepsis and ensuing multiple organ failure continue to be the most leading cause of death in critically ill patients. Despite hepatocyte-related dysfunctions such as necrosis, apoptosis as well as mitochondrial damage are observed in the process of sepsis, the molecular mechanism of pathogenesis remains uncertain. We recently identified one of the differentially expressed genes, mitochondrial ATPase inhibitor protein (IF1) which is down-regulated in late septic liver. Hence, we further hypothesized that the variation of IF1 protein may be one of the causal events of the hepatic dysfunction during late sepsis. The results showed that the elevated mitochondrial F0F1-ATPase activity is concomitant with the decline of intramitochondrial ATP concentration in late septic liver. In addition, the key finding of this study showed that the mRNA and the mitochondrial content of IF1 were decreased in late sepsis while no detectable IF1 was found in cytoplasm. When analyzed by immunoprecipitation, it seems reasonable to imply that the association capability of IF1 with F1-ATPase beta-subunit is not affected. These results confirm the first evidence showing that the suppression of IF1 expression and subsequent elevated mitochondrial F0F1-ATPase activity might contribute to the bioenergetic failure in the liver during late sepsis.

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It has been shown that phosphodiesterase 5 (PDE5) inhibitors have anticancer effects in a variety of malignancies in both in vivo and in vitro experiments. The role of cGMP elevation in colorectal carcinoma (CRC) has been extensively studied. Additionally, DNA topoisomerase II (Topo II) inhibition is a well-established mechanism of action that mediates the effects of several approved anticancer drugs such as doxorubicin and mitoxantrone. Herein, we present 9-benzylaminoacridine derivatives as dual inhibitors of the PDE5 and Topo II enzymes. We synthesized 31 derivatives and evaluated them against PDE5, whereby 22 compounds showed micromolar or sub-micromolar inhibition. The anticancer activity of the compounds was evaluated with the NCI 60-cell line testing. Moreover, the effects of the compounds on HCT-116 colorectal carcinoma (CRC) were extensively studied, and potent compounds against HCT-116 cells were studied for their effects on Topo II, cell cycle progression, and apoptosis. In addition to exhibiting significant growth inhibition against HCT116 cells, compounds 11, 12, and 28 also exhibited the most superior Topo II inhibitory activity and low micromolar PDE5 inhibition and affected cell cycle progression. Knowing that compounds that combat cancer through multiple mechanisms are among the best candidates for effective therapy, we believe that the current class of compounds merits further optimization and investigation to unleash their full therapeutic potential.