The unique ability of tumour cells to proliferate indefinitely is crucial to neoplastic progression as it allows these cells to express the aggressive properties of cancer without the censure of physiological ageing. This is in contrast to normal somatic cells which are subject to a "mitotic clock," a phenomenon that has been linked to telomeric shortening after each round of cell replication, so that eventually the loss of genetic material reaches a critical stage and the cells undergo senescence and cell death. A study was conducted to investigate the role of telomerase, an RNA-containing enzyme that restores the telomere length, in the neoplastic cell immortalization and progression process. Fresh human tissue samples taken from excision specimens received by the Department of Pathology, University of Malaya Medical Centre, were investigated for telomerase activity using a commercial Telomerase PCR-ELISA kit (Boehringer Mannheim). Specimens comprised 33 breast lesions (10 infiltrating breast adenocarcinoma, 13 fibroadenoma and 10 non-neoplastic breast tissue), 27 colonic lesions (17 colonic adenocarcinoma and 10 non-neoplastic colonic mucosa) and 42 cervical lesions (20 cervical carcinoma and 22 non-neoplastic cervical tissues). Telomerase activity was found in 6 (60%) of 10 breast carcinomas, 6 (46%) of 13 fibroadenomas, none of the 10 nonneoplastic breast samples, 3 (17.6%) of 17 colon carcinomas and none of the 10 non-neoplastic colonic mucosal samples, 12 (60%) of 20 cervical carcinoma and 3 (13.6%) of 22 non-neoplastic cervical samples. 5/10 (50%) Stage I, 4/7 (57%) Stage II, 2/2 (100%) Stage III and 1/1 (100%) Stage IV cervical carcinomas showed telomerase activity. These findings support a contributory role for telomerase in tumourigenesis with activation occurring from neoplastic transformation and increasing with tumour progression.
Telomerase ; seconds ; Breast ; neoplastic cell ; Progression

Metastasising ability connotes one of the most important life-threatening properties of malignant neoplasms. Recent studies indicate that CD44 proteins, multifunctional cell adhesion molecules which contribute to "homing" of lymphocytes to lymph nodes as well as cell-cell and cell-matrix interactions, are potential markers of tumour progression. However, whether CD44 expression by human tumours contribute to increased metastatic risk remains controversial. In an attempt to clarify its role in breast cancer, we have investigated the correlation between CD44 expression by breast carcinoma and the presence of axillary lymph node metastases. CD44 expression was detected using a standard immunoperoxidase method on formalin-fixed, paraffin-embedded, primary infiltrating ductal breast carcinoma tissues taken from 60 female patients who underwent mastectomy with axillary node clearance. Tumours were graded according to the modified Bloom and Richardson criteria. 62% of patients had histologically-proven lymph node metastasis. 40% of primary cancers exhibited cytoplasmic membrane immunopositivity for CD44. 46% of primary tumours which have metastasied to axillary lymph nodes were CD44 positive whereas 30% of tumours which have not metastasised expressed CD44. CD44 positivity was expressed by 20% of grade 1, 31% grade 2 and 58% grade 3 tumours. Our results suggest that CD44 may have a role in the progression of breast cancer and emphasise the need to investigate its interaction with other mechanisms of cancer advancement.
Antigens, CD44 ; lymph nodes ; Neoplasm Metastasis ; Cells ; Malignant neoplasm of breast

Background: Adipose tissue provides an abundant source of multipotent cells, which represent a source of cell-based regeneration strategies for urinary bladder smooth muscle repair. Our objective was to confirm that adipose-derived stem cells (ADSCs) can be differentiated into smooth muscle cells. Methods: In this study, adipose tissue samples were digested with 0.075% collagenase, and the resulting ADSCs were cultured and expanded in vitro. ADSCs at passage two were differentiated by incubation in smooth muscle inductive media (SMIM) consisting of MCDB I31 medium, 1% FBS, and 100 U/mL heparin for three and six weeks. ADSCs in non-inductive media were used as controls. Characterisation was performed by cell morphology and gene and protein expression. Result: The differentiated cells became elongated and spindle shaped, and towards the end of six weeks, sporadic cell aggregation appeared that is typical of smooth muscle cell culture. Smooth muscle markers (i.e. alpha smooth muscle actin (ASMA), calponin, and myosin heavy chain (MHC)) were used to study gene expression. Expression of these genes was detected by PCR after three and six weeks of differentiation. At the protein expression level, ASMA, MHC, and smoothelin were expressed after six weeks of differentiation. However, only ASMA and smoothelin were expressed after three weeks of differentiation. Conclusion: Adipose tissue provides a possible source of smooth muscle precursor cells that possess the potential capability of smooth muscle differentiation. This represents a promising alternative for urinary bladder smooth muscle repair.
Adipose Tissue ; Stem Cells ; Muscle Cells ; Regeneration ; Urinary Bladder

BACKGROUND: Tendon and ligament injuries accounted for 30% of all musculoskeletal consultations with 4 million new incidences worldwide each year and thus imposed a significant burden to the society and the economy. Damaged tendon and ligament can severely affect the normal body movement and might lead to many complications if not treated promptly and adequately. Current conventional treatment through surgical repair and tissue graft are ineffective with a high rate of recurrence.METHODS: In this review, we first discussed the anatomy, physiology and pathophysiology of tendon and ligament injuries and its current treatment. Secondly, we explored the current role of tendon and ligament tissue engineering, describing its recent advances. After that, we also described stem cell and cell secreted product approaches in tendon and ligament injuries. Lastly, we examined the role of the bioreactor and mechanical loading in in vitro maturation of engineered tendon and ligament.RESULTS: Tissue engineering offers various alternative ways of treatment from biological tissue constructs to stem cell therapy and cell secreted products. Bioreactor with mechanical stimulation is instrumental in preparing mature engineered tendon and ligament substitutes in vitro.CONCLUSIONS: Tissue engineering showed great promise in replacing the damaged tendon and ligament. However, more study is needed to develop ideal engineered tendon and ligament.
Bioreactors ; Exosomes ; In Vitro Techniques ; Incidence ; Ligaments ; Physiology ; Recurrence ; Referral and Consultation ; Stem Cells ; Tendons ; Tissue Engineering ; Transplants

BACKGROUND: The urinary tract can be affected by both congenital abnormalities as well as acquired disorders, such ascancer, trauma, infection, inflammation, and iatrogenic injuries, all of which may lead to organ damage requiring eventualreconstruction. As a gold standard, gastrointestinal segment is used for urinary bladder reconstruction. However, one majorproblem is that while bladder tissue prevents reabsorption of specific solutes, gastrointestinal tissue actually absorbs them.Therefore, tissue engineering approach had been attempted to provide an alternative tissue graft for urinary bladderreconstruction. METHODS: Human adipose-derived stem cells isolated from fat tissues were differentiated into smooth muscle cells andthen seeded onto a triple-layered PLGA sheet to form a bladder construct. Adult athymic rats underwent subtotal urinarybladder resection and were divided into three treatment groups (n = 3): Group 1 (‘‘sham’’) underwent anastomosis of theremaining basal region, Group 2 underwent reconstruction with the cell-free scaffold, and Group 3 underwent reconstructionwith the tissue-engineered bladder construct. Animals were monitored on a daily basis and euthanisation wasperformed whenever a decline in animal health was detected. RESULTS: All animals in Groups 1, 2 and 3 survived for at least 7 days and were followed up to a maximum of 12 weekspost-operation. It was found that by Day 14, substantial ingrowth of smooth muscle and urothelial cells had occurred inGroup 2 and 3. In the long-term follow up of group 3 (tissue-engineered bladder construct group), it was found that theurinary bladder wall was completely regenerated and bladder function was fully restored. Urodynamic and radiologicalevaluations of the reconstructed bladder showed a return to normal bladder volume and function.Histological analysisrevealed the presence of three muscular layers and a urothelium similar to that of a normal bladder. Immunohistochemicalstaining using human-specific myocyte markers (myosin heavy chain and smoothelin) confirmed the incorporation of theseeded cells in the newly regenerated muscular layers. CONCLUSION Implantation of PLGA construct seeded with smooth muscle cells derived from human adipose stemcells can lead to regeneration of the muscular layers and urothelial ingrowth, leading to formation of a completelyfunctional urinary bladder.

BACKGROUND: Managing massive bone defects, a great challenge to orthopaedics reconstructive surgery. The problem arise is the supply of suitable bone is limited with many complications. Tissue-engineered hydroxyapatite bone (TEHB) scaffold impregnated with osteoprogenitor cells developed as an alternative to promote bone regeneration. METHODS: This animal protocol has been approved by Universiti Kebangsaan Malaysia Animal Ethical Committee. The TEHB scaffold prepared from hydroxyapatite using gel casting method. A total of six adolescent female sheep were chosen for this study. Later, all the sheep were euthanized in a proper manner and the bone harvested for biomechanical study.Bone marrow was collected from iliac crest of the sheep and bone marrow stem cells (BMSCs) isolated and cultured. BMSCs then cultured in osteogenic medium for osteoprogenitor cells development and the plasma collected was seeded with osteoprogenitor cells mixed with calcium chloride. Bone defect of 3 cm length of tibia bone created from each sheep leg and implanted with autologous and TEHB scaffold in 2 different groups of sheep. Wound site was monitored weekly until the wound completely healed and conventional X-ray performed at week 1 and 24. Shear test was conducted to determine the shear force on the autologous bone and TEHB scaffold after implantation for 24 weeks. RESULTS: All of the sheep survived without any complications during the study period and radiograph showed new bone formation. Later, the bone harvested was for biomechanical study. The highest shear force for the autologous group was 13 MPa and the lowest was 5 MPa while for the scaffold group, the highest was 10 MPa and the lowest was 3 MPa.Although, proximal and distal interface of autologous bone graft shows higher shear strength compared to the TEHB scaffold but there is no significant difference in both groups, p value [ 0.05. Histologically in both proximal and distal interface in both arms shows bone healing and woven bone formation. CONCLUSION TEHB scaffold impregnated with osteoprogenitor cells has the potential to be developed as a bone substitute in view of its strength and capability to promote bone regeneration.

BACKGROUND: The urinary tract can be affected by both congenital abnormalities as well as acquired disorders, such ascancer, trauma, infection, inflammation, and iatrogenic injuries, all of which may lead to organ damage requiring eventualreconstruction. As a gold standard, gastrointestinal segment is used for urinary bladder reconstruction. However, one majorproblem is that while bladder tissue prevents reabsorption of specific solutes, gastrointestinal tissue actually absorbs them.Therefore, tissue engineering approach had been attempted to provide an alternative tissue graft for urinary bladderreconstruction. METHODS: Human adipose-derived stem cells isolated from fat tissues were differentiated into smooth muscle cells andthen seeded onto a triple-layered PLGA sheet to form a bladder construct. Adult athymic rats underwent subtotal urinarybladder resection and were divided into three treatment groups (n = 3): Group 1 (‘‘sham’’) underwent anastomosis of theremaining basal region, Group 2 underwent reconstruction with the cell-free scaffold, and Group 3 underwent reconstructionwith the tissue-engineered bladder construct. Animals were monitored on a daily basis and euthanisation wasperformed whenever a decline in animal health was detected. RESULTS: All animals in Groups 1, 2 and 3 survived for at least 7 days and were followed up to a maximum of 12 weekspost-operation. It was found that by Day 14, substantial ingrowth of smooth muscle and urothelial cells had occurred inGroup 2 and 3. In the long-term follow up of group 3 (tissue-engineered bladder construct group), it was found that theurinary bladder wall was completely regenerated and bladder function was fully restored. Urodynamic and radiologicalevaluations of the reconstructed bladder showed a return to normal bladder volume and function.Histological analysisrevealed the presence of three muscular layers and a urothelium similar to that of a normal bladder. Immunohistochemicalstaining using human-specific myocyte markers (myosin heavy chain and smoothelin) confirmed the incorporation of theseeded cells in the newly regenerated muscular layers. CONCLUSION Implantation of PLGA construct seeded with smooth muscle cells derived from human adipose stemcells can lead to regeneration of the muscular layers and urothelial ingrowth, leading to formation of a completelyfunctional urinary bladder.

BACKGROUND: Managing massive bone defects, a great challenge to orthopaedics reconstructive surgery. The problem arise is the supply of suitable bone is limited with many complications. Tissue-engineered hydroxyapatite bone (TEHB) scaffold impregnated with osteoprogenitor cells developed as an alternative to promote bone regeneration. METHODS: This animal protocol has been approved by Universiti Kebangsaan Malaysia Animal Ethical Committee. The TEHB scaffold prepared from hydroxyapatite using gel casting method. A total of six adolescent female sheep were chosen for this study. Later, all the sheep were euthanized in a proper manner and the bone harvested for biomechanical study.Bone marrow was collected from iliac crest of the sheep and bone marrow stem cells (BMSCs) isolated and cultured. BMSCs then cultured in osteogenic medium for osteoprogenitor cells development and the plasma collected was seeded with osteoprogenitor cells mixed with calcium chloride. Bone defect of 3 cm length of tibia bone created from each sheep leg and implanted with autologous and TEHB scaffold in 2 different groups of sheep. Wound site was monitored weekly until the wound completely healed and conventional X-ray performed at week 1 and 24. Shear test was conducted to determine the shear force on the autologous bone and TEHB scaffold after implantation for 24 weeks. RESULTS: All of the sheep survived without any complications during the study period and radiograph showed new bone formation. Later, the bone harvested was for biomechanical study. The highest shear force for the autologous group was 13 MPa and the lowest was 5 MPa while for the scaffold group, the highest was 10 MPa and the lowest was 3 MPa.Although, proximal and distal interface of autologous bone graft shows higher shear strength compared to the TEHB scaffold but there is no significant difference in both groups, p value [ 0.05. Histologically in both proximal and distal interface in both arms shows bone healing and woven bone formation. CONCLUSION TEHB scaffold impregnated with osteoprogenitor cells has the potential to be developed as a bone substitute in view of its strength and capability to promote bone regeneration.

Umbilical cord (UC) is a discarded product from the operating theatre and a ready source of mesenchymal stromal cells (MSCs). MSCs from UC express both embryonic and adult mesenchymal stem cell markers and are known to be hypoimmunogenic and non-tumorigenic and thus suitable for allogeneic cell transplantation. Our study aimed to determine the degree of immunotolerance and bone-forming capacity of osteodifferentiated human Wharton's jelly-derived mesenchymal stromal cells (hWJ-MSCs) from different segments of UC in an allogenic setting. UCs were obtained from healthy donors delivering a full-term infant by elective Caesarean section. hWJ-MSCs were isolated from 3 cm length segment from the maternal and foetal ends of UCs. Three-dimensional fibrin constructs were formed and implanted intramuscularly into immunocompetent mice. The mice were implanted with 1) fibrin construct with maternal hWJ-MSCs, 2) fibrin construct with foetal hWJ-MSCs, or 3) fibrin without cells; the control group received sham surgery. After 1 month, the lymphoid organs were analysed to determine the degree of immune rejection and bone constructs were analysed to determine the amount of bone formed. A pronounced immune reaction was noted in the fibrin group. The maternal segment constructs demonstrated greater osteogenesis than the foetal segment constructs. Both maternal and foetal segment constructs caused minimal immune reaction and thus appear to be safe for allogeneic bone transplant. The suppression of inflammation may be a result of increased anti-inflammatory cytokine production mediated by the hWJ-MSC. In summary, this study demonstrates the feasibility of using bone constructs derived from hWJ-MSCs in an allogenic setting.
Adult ; Animals ; Bone Regeneration ; Cell Transplantation ; Cesarean Section ; Female ; Fibrin ; Humans ; Infant ; Inflammation ; Mesenchymal Stromal Cells ; Mice ; Osteogenesis ; Pregnancy ; Tissue Donors ; Tissue Engineering ; Transplants ; Umbilical Cord ; Wharton Jelly

BACKGROUND: Different methods have been used to inject stem cells into the eye for research. We previously explored the intravitreal route. Here, we investigate the efficacy of intravenous and subretinal-transplanted human dental pulp stem cells (DPSCs) in rescuing the photoreceptors of a sodium iodate-induced retinal degeneration model. METHODS: Three groups of Sprague Dawley rats were used: intervention, vehicle group and negative control groups (n = 6 in each). Intravenous injection of 60 mg/kg sodium iodate (day 0) induced retinal degeneration. On day 4 postinjection of sodium iodate, the rats in the intervention group received intravenous DPSC and subretinal DPSC in the right eye; rats in the vehicle group received subretinal Hank’s balance salt solution and intravenous normal saline; while negative control group received nothing. Electroretinogram (ERG) was performed to assess the retinal function at day 0 (baseline), day 4, day 11, day 18, day 26, and day 32. By the end of the study at day 32, the rats were euthanized, and both their enucleated eyes were sent for histology. RESULTS: No significant difference in maximal ERG a-wave (p = 0.107) and b-wave, (p= 0.153) amplitude was seen amongst the experimental groups. However, photopic 30 Hz flicker amplitude of the study eye showed significant differences in the 3 groups (p = 0.032). Within the intervention group, there was an improvement in 30 Hz flicker ERG response of all 6 treated right eyes, which was injected with subretinal DPSC; while the 30 Hz flicker ERG of the nontreated left eyes remained flat. Histology showed improved outer nuclear layer thickness in intervention group; however, findings were not significant compared to the negative and vehicle groups. CONCLUSION Combination of subretinal and intravenous injection of DPSCs may have potential to rescue cone function from a NaIO3 -induced retinal injury model.