Novel air-liquid interface culture model to investigate stiffness-dependent behaviors of alveolar epithelial cells.

Pulmonary alveoli are functional units in gas exchange in the lung, and their dysfunctions in lung diseases such as interstitial pneumonia are accompanied by fibrotic changes in structure, elevating the stiffness of extracellular matrix components. The present study aimed to test the hypothesis that such changes in alveoli stiffness induce functional alteration of epithelial cell functions, exacerbating lung diseases. For this, we have developed a novel method of culturing alveolar epithelial cells on polyacrylamide gel with different elastic modulus at an air-liquid interface. It was demonstrated that A549 cells on soft gels, mimicking the modulus of a healthy lung, upregulated mRNA expression and protein synthesis of surfactant protein C (SFTPC). By contrast, the cells on stiff gels, mimicking the modulus of the fibrotic lung, exhibited upregulation of SFTPC gene expression but not at the protein level. Cell morphology, as well as cell nucleus volume, were also different between the two types of gels.

Androgen promotes squamous differentiation of atypical cells in cervical intraepithelial neoplasia via an ELF3-dependent pathway.

BACKGROUND: Since the human papillomavirus vaccines do not eliminate preexisting infections, nonsurgical alternative approaches to cervical intraepithelial neoplasia (CIN) have been required. We previously reported that FOXP4 (forkhead box transcription factor P4) promoted proliferation and inhibited squamous differentiation of CIN1-derived W12 cells. Since it was reported that FOXP expressions were regulated by the androgen/androgen receptor (AR) complex and AR was expressed on the CIN lesions, in this study we examined the effects of androgen on CIN progression. METHODS: Since AR expression was negative in W12 cells and HaCaT cells, a human male skin-derived keratinocyte cell line, we transfected AR to these cell lines and investigated the effects of dihydrotestosterone (DHT) on their proliferation and squamous differentiation. We also examined the immunohistochemical expression of AR in CIN lesions. RESULTS: DHT reduced the intranuclear expression of FOXP4, attenuating cell proliferation and promoting squamous differentiation in AR-transfected W12 cells. Si-RNA treatments showed that DHT induced the expression of squamous differentiation-related genes in AR-transfected W12 cells via an ELF3-dependent pathway. DHT also reduced FOXP4 expression in AR-transfected HaCaT cells. An immunohistochemical study showed that AR was expressed in the basal to parabasal layers of the normal cervical epithelium. In CIN1 and 2 lesions, AR was detected in atypical squamous cells, whereas AR expression had almost disappeared in the CIN3 lesion and was not detected in SCC, suggesting that androgens do not act to promote squamous differentiation in the late stages of CIN. CONCLUSION: Androgen is a novel factor that regulates squamous differentiation in the early stage of CIN, providing a new strategy for nonsurgical and hormone-induced differentiation therapy against CIN1 and CIN2.

FOXP4 inhibits squamous differentiation of atypical cells in cervical intraepithelial neoplasia via an ELF3-dependent pathway.

Although the human papillomavirus (HPV) vaccine is effective for preventing cervical cancers, this vaccine does not eliminate pre-existing infections, and alternative strategies have been warranted. Here, we report that FOXP4 is a new target molecule for differentiation therapy of cervical intraepithelial neoplasia (CIN). An immunohistochemical study showed that FOXP4 was expressed in columnar epithelial, reserve, and immature squamous cells, but not in mature squamous cells of the normal uterine cervix. In contrast with normal mature squamous cells, FOXP4 was expressed in atypical squamous cells in CIN and squamous cell carcinoma lesions. The FOXP4-positive areas significantly increased according to the CIN stages from CIN1 to CIN3. In monolayer cultures, downregulation of FOXP4 attenuated proliferation and induced squamous differentiation in CIN1-derived HPV 16-positive W12 cells via an ELF3-dependent pathway. In organotypic raft cultures, FOXP4-downregulated W12 cells showed mature squamous phenotypes of CIN lesions. In human keratinocyte-derived HaCaT cells, FOXP4 downregulation also induced squamous differentiation via an ELF3-dependent pathway. These findings suggest that downregulation of FOXP4 inhibits cell proliferation and promotes the differentiation of atypical cells in CIN lesions. Based on these results, we propose that FOXP4 is a novel target molecule for nonsurgical CIN treatment that inhibits CIN progression by inducing squamous differentiation.

Microscopic characterisation of local strain field in healing tissue in the central third defect of mouse patellar tendon at early-phase of healing.

Tendons exhibit a hierarchical collagen structure, wherein higher-level components, such as collagen fibres and fascicles, are elongated, slid, and rotated during macroscopic stretching. These mechanical behaviours of collagen fibres play important roles in stimulating tenocytes, imposing stretching, compression, and shear deformation. It was hypothesised that a lack of local fibre behaviours in healing tendon tissue may result in a limited application of mechanical stimuli to cells within the tissue, leading to incomplete recovery of tissue structure and functions in regenerated tendons. Therefore, the present study aimed to measure the microscopic strain field in the healing tendon tissue. A central third defect was created in the patellar tendon of mice, and the regenerated tissue in the defect was examined by tensile testing, collagen fibre analysis, and local strain measurement using confocal microscopy at 3 and 6 weeks after surgery. Healing tissue at 3 weeks exhibited a significantly lower strength and disorganised collagen fibre structure compared with the normal tendon. These characteristics at 6 weeks remained significantly different from those of the normal tendon. Moreover, the magnitude of local shear strain in the healing tissue under 4% tissue strain was significantly smaller than that in the normal tendon. Differences in the local strain field may be reflected in the cell nuclear shape and possibly the amount of mechanical stimuli applied to the cells during tendon deformation. Accordingly, restoration of a normal local mechanical environment in the healing tissue may be key to a better healing outcome of tendon injury.

A direct endoscopic approach for left-sided infrarenal para-aortic lymphadenectomy immediately after hysterectomy for endometrial cancer treatment: left dome formation (LDF).

BACKGROUND: Endoscopic surgery for infrarenal para-aortic lymphadenectomy has been widely accepted. Two major approaches, "transperitoneal" and "extraperitoneal", are generally used; however, they have several disadvantages. A "transperitoneal" approach to the left para-aortic region is usually indirect, often performed after wide extension of the right para-aortic region. An "extraperitoneal" approach is unsuitable when a peritoneal tear exists after a prior surgical procedure such as hysterectomy. Here, we propose a modified transperitoneal technique, "Left dome formation (LDF)," which directly provides a surgical field for left infrarenal para-aortic lymphadenectomy even after hysterectomy. METHODS: The LDF procedure comprised three processes: (1) setting, (2) dissection of inframesenteric lymph nodes (step 1), and (3) dissection of infrarenal lymph nodes (step 2). SETTING: two trocars were added 4 cm bilateral to the low-mid abdominal trocar that was used in prior hysterectomy. Step 1: The posterior layer of the renal fascia along with the left ureter and left ovarian vessel were separated from the left common iliac artery and iliopsoas. Left inframesentric nodes were removed from the surgical field. Step 2: The left ureter was isolated from the posterior renal fascia, and the dome was expanded cranially to the left renal vein, with the ovarian vein always visualizable at the dome ceiling. Left infrarenal nodes were removed. RESULTS: We applied LDF to ten endometrial cancer patients, recommended for additional dissection of para-aortic nodes based on intraoperative evaluation using the laparoscopically removed uterus. The operative time and number of removed lymph nodes in Step 1 and Step 2 were 28.8 (20-49) min and 5.3 (2-10) and 54.6 (52-70) min and 6.5 (1-11), respectively. Blood loss was below 50 ml. No serious organ injury occurred during procedures. CONCLUSION: Since the left ureter is always observable, LDF procedure facilitates effective surgery to overcome the anatomical complexity of the left para-aortic region and is potentially useful for sentinel node sampling.

Shape-dependent regulation of differentiation lineages of bone marrow-derived cells under cyclic stretch.

Multipotent stem cells are considered as a key material in regenerative medicine, and the understanding of the heterogeneity in the differentiation potentials of bone marrow-derived cells is important in the successful regenerative tissue repair. Therefore, the present study has been performed to investigate how the differentiation of post-harvest, native bone marrow-derived cells is regulated by cyclic stretch in vitro. Bone marrow-derived cells were obtained from mouse femur of both hind limbs and categorized into the following five categories: amebocytes, round cells, spindle cells, stellate cells and others. The cells were seeded on a silicone-made stretch chamber, and subjected to cyclic stretch with an amplitude of 10% at a frequency of 1 Hz for 7 days for cell shape analysis and for 3 days for the analysis of the expression of marker proteins of osteogenic (osteocalcin), vascular smooth muscle (α-smooth muscle actin and smooth muscle myosin heavy chain) and neurogenic (neurofilament) differentiation. When disregarding the differences in the cell shapes, there was an overall trend that the application of 10% cyclic stretch inhibited osteogenic and neurogenic differentiation, but enhanced smooth muscle differentiation. Close examinations revealed that round cells were influenced the most by cyclic stretch (significant up- or down-regulation in all the four marker protein expressions) while amebocytes and spindle cells were only influenced by cyclic stretch for vascular smooth muscle and/or neurogenic differentiation. As far as the authors know, this is the first study reporting the shape-related differences in the fate decision criteria for mechanical strain in bone marrow-derived cells.

Detection of circulating tumor cells in cervical cancer using a conditionally replicative adenovirus targeting telomerase-positive cells.

Circulating tumor cells (CTC) are newly discovered biomarkers of cancers. Although many systems detect CTC, a gold standard has not yet been established. We analyzed CTC in uterine cervical cancer patients using an advanced version of conditionally replicative adenovirus targeting telomerase-positive cells, which was enabled to infect coxsackievirus-adenovirus receptor-negative cells and to reduce false-positive signals in myeloid cells. Blood samples from cervical cancer patients were hemolyzed and infected with the virus and then labeled with fluorescent anti-CD45 and anti-pan cytokeratin antibodies. GFP (+)/CD45 (-) cells were isolated and subjected to whole-genome amplification followed by polymerase chain reaction analysis of human papillomavirus (HPV) DNA. CTC were detected in 6 of 23 patients with cervical cancers (26.0%). Expression of CTC did not correlate with the stage of cancer or other clinicopathological factors. In 5 of the 6 CTC-positive cases, the same subtype of HPV DNA as that of the corresponding primary lesion was detected, indicating that the CTC originated from HPV-infected cancer cells. These CTC were all negative for cytokeratins. The CTC detected by our system were genetically confirmed. CTC derived from uterine cervical cancers had lost epithelial characteristics, indicating that epithelial marker-dependent systems do not have the capacity to detect these cells in cervical cancer patients.

Subserous invasion of VEGF-C-producing cancer cells is a possible risk factor for ileal ulceration in the non-metastatic mucosal layer during bevacizumab-combined chemotherapy for recurrent ovarian cancer: A case report.

A 65-year-old woman received chemotherapy using taxane and carboplatin prior and following optimal debulking surgery for ovarian cancer stage IV. Five months later, intra-abdominal recurrence was diagnosed, and second-line chemotherapy using nogitecan and bevacizumab was administered. After five courses, the patient presented with a symptom of subileus and subsequent intestinal perforation occurred. An emergent surgery revealed two perforation sites and longitudinally extended ulcerative lesions in the ileum. Pathologically, although metastatic sites were not observed in the submucus layer just beneath the ulcers, there were a number of vascular endothelial growth factor (VEGF)-C-positive cancer cell invasion sites along with marked edema and an increase of the lymphatic endothelial cell marker 'podoplanin'-positive cells in subserous regions. Since bevacizumab is able to inhibit VEGF-A, but not VEGF-C, and induce compensatory increase in VEGF-C production, these findings suggest that the local disturbance of lymphatic circulation in the subserous regions by VEGF-C-producing cancer cells is a possible risk factor for the development of intestinal ulceration and perforation during bevacizumab therapy.

Synchronous endometrioid adenocarcinomas in the uterine cervix and corpus.

It is frequently difficult to distinguish multiple primary carcinomas from single primary carcinoma with metastasis. Here, we report a case of synchronous endometrioid adenocarcinomas that independently occurred in the uterine cervix and corpus. A 47-year-old woman complaining of genital bleeding was preoperatively diagnosed with cervical adenocarcinoma with an endometrial lesion. On surgical treatment, two separate malignant lesions bearing endometrioid adenocarcinoma were identified in the uterine cervix and cavity. Although both lesions expressed the same type of human papillomavirus (HPV) gene, type 16, microscopic continuity was not observed. Furthermore, we detected a critical difference in PTEN mutation between the tumors and finally diagnosed this case as multiple primary cancers. This is the first report to show multiple primary endometrioid adenocarcinomas simultaneously arising in the uterine cervix and corpus. Considering the rarity of this case, the coexistence of HPV suggests its possible involvement in the carcinogenesis of the endometrioid adenocarcinomas.

Mechanical trapping of the nucleus on micropillared surfaces inhibits the proliferation of vascular smooth muscle cells but not cervical cancer HeLa cells.

The interaction between cells and the extracellular matrix on a topographically patterned surface can result in changes in cell shape and many cellular functions. In the present study, we demonstrated the mechanical deformation and trapping of the intracellular nucleus using polydimethylsiloxane (PDMS)-based microfabricated substrates with an array of micropillars. We investigated the differential effects of nuclear deformation on the proliferation of healthy vascular smooth muscle cells (SMCs) and cervical cancer HeLa cells. Both types of cell spread normally in the space between micropillars and completely invaded the extracellular microstructures, including parts of their cytoplasm and their nuclei. We found that the proliferation of SMCs but not HeLa cells was dramatically inhibited by cultivation on the micropillar substrates, even though remarkable deformation of nuclei was observed in both types of cells. Mechanical testing with an atomic force microscope and a detailed image analysis with confocal microscopy revealed that SMC nuclei had a thicker nuclear lamina and greater expression of lamin A/C than those of HeLa cells, which consequently increased the elastic modulus of the SMC nuclei and their nuclear mechanical resistance against extracellular microstructures. These results indicate that the inhibition of cell proliferation resulted from deformation of the mature lamin structures, which might be exposed to higher internal stress during nuclear deformation. This nuclear stress-induced inhibition of cell proliferation occurred rarely in cancer cells with deformable nuclei.

Mechanical properties and function of the spinal pia mater.

OBJECT: The pia mater has received little attention regarding its function in the deformation of the spinal cord under compression. In this study the mechanical properties and function of the spinal pia mater were investigated using three methods. METHODS: Spinal cord segments were excised from rabbits. The elastic modulus of the pia mater was measured by performing a tensile test using specimens with the pia mater intact and ones with the pia mater stripped off. The stiffness of the spinal cord was examined by performing a compression test with specimens containing an intact pia mater and ones with a pia mater that was incised at both sides. The cross-sectional area and circumference of the spinal cord were measured on axial views of magnetic resonance images in patients with cervical disc herniations before and after surgery. The pia mater had an elastic modulus of 2300 kPa, which was 460 times higher than that of spinal cord parenchyma. By covering the parenchyma, it tripled the overall elastic modulus of the spinal cord. The pia mater increased the stiffness of the spinal cord and enhanced its shape recovery after removal of the compression. The cross-sectional area of the spinal cord increased after surgery, whereas the circumference of the spinal cord changed little. CONCLUSIONS: The pia mater firmly covers the spinal cord and has a high elastic modulus; it therefore provides a constraint on the spinal cord surface. It prevents elongation of the circumference and produces a large strain energy that is responsible for shape restoration following decompression.