Cancer progression is associated with increased expression of basement membrane proteins in three-dimensional in vitro models of human oral cancer

Background

Although basement membrane was traditionally considered an inert barrier that tumour cells had to cross before invasion into the surrounding stroma, recent studies suggest that basement membrane components are not only degraded during tumour progression, but also newly synthesised at the invasive front.

Objective

This study aimed at evaluating (1) the expression of basement membrane proteins in human oral carcinogenesis and (2) the role that epithelial-mesenchymal interactions play on it, by using an in vitro oral cancer progression model.

Material and methods

In vitro three-dimensional (3D) organotypic cultures of normal, early neoplastic and neoplastic human oral mucosa were developed by growing primary normal human oral keratinocytes, dysplastic human oral keratinocytes (DOK cell line), and neoplastic human oral keratinocytes (PE/CA-PJ15 cell line) on type I collagen biomatrices, with or without primary fibroblasts isolated from normal human oral mucosa. The cultured tissues were immunohistochemically assessed for the expression of the major basement membrane proteins laminin-332, type IV collagen, and fibronectin.

Results

Expression of laminin-332, type IV collagen, and fibronectin was gradually more pronounced in neoplastic models when compared to normal mucosa models, and, with the exception of laminin-332, it was further enhanced by presence of fibroblasts. Deposition of type IV collagen at the epithelium-biomatrix interface occurred only in presence of fibroblasts, as well as the extracellular matrix deposition of fibronectin.

Conclusions

These findings, obtained in a 3D in vitro model that closely mirrors the in vivo human oral cancer progression, show an enhanced basement membrane protein expression during human oral cancer progression that is dependent on the epithelial-mesenchymal environment, respectively the existence of fibroblasts.     

Khat induces G1-phase arrest and increased expression of stress-sensitive p53 and p16 proteins in normal human oral keratinocytes and fibroblasts

Khat is a psychostimulant plant used by over 10 million people daily, mainly in eastern Africa and the Middle East. Previous studies have suggested an association between khat use and oral lesions such as hyperkeratosis and oral cancer. This study investigated the effects of an extract of khat on primary normal human oral keratinocytes (NOK) and normal human oral fibroblasts (NOF). Low (sublethal) concentrations of khat inhibited the proliferation of both cell types in a dose-dependent and time-dependent manner. Both NOK and NOF treated with khat accumulated in the G1-phase of the cell cycle and showed increased expression of the stress-sensitive p53 protein after 24 h. Normal human oral keratinocytes showed a profound increase in p16^INK4A (p16) after 24 h and showed morphological changes suggesting cell differentiation. Normal human oral fibroblasts showed growth inhibition and increased expression of p21^WAF1/CIP1 (p21) within 24 h. The concentrations of khat tested in this study were within the range of those found in the oral cavity of khat chewers. The results show that stress induced by khat modulates the cell cycle in oral keratinocytes and fibroblasts. It is further speculated whether khat could have similar effects in vivo , especially in keratinocytes.     

Radiological findings correlate with neurological deficits but not with pain after operatively treated sacral fractures: An 11-year follow-up study of 28 patients

Background and purpose

Neurological deficits and pain are common after displaced sacral fractures. However, little is known about the association between the long-term clinical outcomes and radiological findings. We examined the long-term radiological findings and their correlations with lumbosacral pain and neurological deficits in the lower extremities after surgery for sacral fractures.

Methods

28 consecutive patients with operatively treated displaced sacral fractures were followed for mean 11 (8–13) years. Sensorimotor impairments of the lower extremities were classified according to the American Spinal Injury Association (ASIA). Pain was assessed using a visual analog scale (VAS). All patients underwent conventional radiographic examination and CT, and the images were scrutinized for nonunion, residual displacement, narrowing of the sacral foramina, and post-foraminal encroachment of the L5 and S1 nerves.

Results

There was residual displacement of ≥ 10 mm in 16 of the 28 patients. 26 patients had narrowing of 1 or more neural root foramina in L5-S4. 8 patients reported having no pain, 11 had pain only in the lumbosacral area, and 9 had pain in combination with radiating leg pain. Statistically significant correlations were found between narrowing of the sacral foramina and neurological deficits in the corresponding dermatomes. Significant correlations were also found between post-foraminal encroachment of L5 nerves and both sensory and motor deficits. No correlations were found between pain and radiological findings.

Interpretation

Pathological radiological findings are common 11 years after operatively treated displaced sacral fractures. Sacral foraminal and L5 post-foraminal bony encroachments were common findings and correlated with neurological deficits. However, lumbosacral pain did not correlate with radiological sequelae after fracture healing.High-energy trauma with displaced sacral fracture is frequently associated with concomitant injuries to the intrapelvic soft tissue structures, including the lumbosacral plexus (Huittinen 1972, Denis et al. 1988, Majeed 1992). These injuries may cause considerable morbidity (Pohlemann et al. 1994, Tornetta and Matta 1996, Tötterman et al. 2006). However, little is known about which factors determine long-term clinical outcome in these patients, or what may explain the progression of neurological symptoms observed in a small proportion of patients (Adelved et al. 2012). Pelvic malunions and nonunions have been put forward as prognostic factors for impaired long-term outcome (Matta et al. 1996, Mears and Velyvis 2003, Oransky and Tortora 2007), but long-term structural changes of the sacrum after fracture healing have not been explored.Our primary aim was to assess long-term radiological findings after surgically treated displaced sacral fractures. In addition, we wanted to assess whether pathological radiological findings, including bony structural changes of the sacrum, may contribute to neurological dysfunctions of the lower extremities or to the occurrence of pelvis-related pain.     

Small and similar amounts of micromotion in an anatomical stem and a customized cementless femoral stem in regular-shaped femurs: A 5-year follow-up randomized RSA study

Background and purpose

High primary stability is important for long-term survival of uncemented femoral stems. Different stem designs are currently in use. The ABG-I is a well-documented anatomical stem with a press-fit design. The Unique stem is designed for a tight customized fit to the cortical bone of the upper femur. This implant was initially developed for patients with abnormal anatomy, but the concept can also be used in patients with normal femoral anatomy. We present 5-year radiostereometric analysis (RSA) results from a randomized study comparing the ABG-I anatomical stem with the Unique femoral stem.

Patients and methods

100 hips with regular upper femur anatomy were randomized to either the ABG-I stem or the Unique femoral stem. RSA measurements were performed postoperatively and after 3, 6, 12, 24, and 60 months.

Results

RSA measurements from 80 hips were available for analysis at the 5-year follow-up. Small amounts of movement were observed for both stems, with no statistically significant differences between the 2 types.

Interpretation

No improvement in long-term stability was found from using a customized stem design. However, no patients with abnormal geometry of the upper femur were included in this study.High mechanical stability is a crucial factor for correct performance of uncemented femoral stems. Micromovements along the implant-bone interface may prevent ingrowth of bone to the surface of the prosthesis, and it may lead to the formation of a fibrous membrane and eventually to loosening of the implant. The critical thresholds of micromovements that can be tolerated are not exactly known, but they are probably dependent on both patient- and implant-specific factors (Viceconti et al. 2006). It has been shown, however, that interfacial motion of around 40 μm leads to partial bone ingrowth whereas motions exceeding 150 μm completely prevent ingrowth of bone (Pilliar et al. 1986, Jasty et al. 1997).Uncemented, customized femoral stems are mainly designed and manufactured for patients with abnormal size and shape of the proximal femur, but this does not preclude their use in patients with regular-shaped proximal femurs. The requirement for maximum primary stability with uncemented off-the-shelf stems also applies to customized stems. The optimized fit and fill of a customized stem should theoretically promote even better mechanical fixation than with standard implants.Radiostereometric analysis (RSA) enables measurement of migration and rotation in the range of 0.1 mm and 0.05º, respectively (Selvik 1989, Kadar et al. 2011). There is a correlation between postoperative migration of femoral stems and early loosening (Freeman and Plante-Bordeneuve 1994, Linder 1994, Karrholm et al. 2006, Karrholm 2012). On the other hand, a new implant showing large degrees of micromovement should not necessarily be regarded as having a performance equivalent to long-term failure (Karrholm et al. 2006). Recently published studies reporting medium- to long-term RSA results will probably contribute to a better understanding of the topic (Nieuwenhuijse et al. 2012, Rohrl et al. 2012).This randomized study was performed as part of the clinical documentation of the Unique customized stem (Scandinavian Customized Prosthesis (SCP), Trondheim, Norway), to compare the migration pattern of the Unique stem with that of a standard anatomical uncemented stem with a clinically well-proven stem design (the ABG-I).Our aim was to measure migration of the Unique customized stem and the ABG-I stem using RSA. Our hypothesis was that there would be no difference in migration between the 2 types of uncemented femoral stems in patients with regular anatomy in the upper femur.     

Building a Patient Ombudsman scheme: the Norwegian experience

The Patient Ombudsman scheme in Norway has gradually been established over the last 25 years, and has its basis in the Patients' Rights Act. The 18 ombudsmen are obliged to assist all users of health services. The question mainly to be dealt with is twofold: In which ways are the aims of the Patient Ombudsmen scheme attended to by the ombudsmen? What do the ombudsmen look upon as key elements in building a functional system? This is examined by means of data from the Norwegian Social Science Data Services, the Norwegian Board of Health Supervision and from a questionnaire presented to the ombudsmen. Besides giving information the ombudsmen take roles as advisors, mediators, advocates and arbitrators. Among the key elements in building a well functioning scheme the ombudsmen in particular mentioned; working independently of health care authorities, the right to investigate cases, and the possibility to make use of the supervisory authority.