Mechanical stretch induces hair regeneration through the alternative activation of macrophages.

Tissues and cells in organism are continuously exposed to complex mechanical cues from the environment. Mechanical stimulations affect cell proliferation, differentiation, and migration, as well as determining tissue homeostasis and repair. By using a specially designed skin-stretching device, we discover that hair stem cells proliferate in response to stretch and hair regeneration occurs only when applying proper strain for an appropriate duration. A counterbalance between WNT and BMP-2 and the subsequent two-step mechanism are identified through molecular and genetic analyses. Macrophages are first recruited by chemokines produced by stretch and polarized to M2 phenotype. Growth factors such as HGF and IGF-1, released by M2 macrophages, then activate stem cells and facilitate hair regeneration. A hierarchical control system is revealed, from mechanical and chemical signals to cell behaviors and tissue responses, elucidating avenues of regenerative medicine and disease control by demonstrating the potential to manipulate cellular processes through simple mechanical stimulation.

Cancer Risks in Vitiligo Patients: A Nationwide Population-Based Study in Taiwan.

Vitiligo is an autoimmune disease characterized by destruction of melanocytes and associated with other autoimmune disease. Whether the dysregulation of immune system enhances oncogenesis or not remains obscure. Until now, no nationwide population-based study has been conducted regarding this. As such, this paper aims to clarify cancer risk in vitiligo patients. A retrospective nationwide population-based cohort study between 2000 and 2010 was performed based on data from the National Health Insurance Research Database of Taiwan. Standardized incidence ratios (SIRs) of cancers were analyzed. Among the 12,391 vitiligo patients (5364 males and 7027 females) and 48,531.09 person-years of observation, a total of 345 cancers were identified. Significantly increased SIRs were observed for prostate cancer in male patients, thyroid cancer and breast cancer in female patients and bladder cancers in both male and female patients. Unfortunately, the low incidence rate of certain cancers limited the power of our statistical analyses. This study demonstrated the patterns of malignancies in vitiligo patients of Taiwan. Compared with the general population, male patients had higher risks of prostate cancer and female patients had higher risks of thyroid cancer and breast cancer. The risks of bladder cancer were also increased in both male and female patients.

Cancer risk in patients with allergic rhinitis, asthma and atopic dermatitis: a nationwide cohort study in Taiwan.

It has long been a debate that whether atopy is a risk factor or protective factor for cancer. However, no large-scale study of different cancers in patients with atopic diseases has been conducted among Asians. Here, we conducted a nationwide study to evaluate the cancer risk in patients with allergic rhinitis (AR), asthma and atopic dermatitis (AD). Drawing on Taiwan's National Health Insurance Research Database, 225,315 patients with AR, 107,601 patients with asthma and 34,263 patients with AD without prior cancers were identified in the period from 1996 to 2008. The standard incidence ratio (SIR) of each cancer was calculated. Although the overall cancer risks in patients with atopic symptoms were not increased, the risks were slightly elevated in female patients with AR or asthma (SIR: 1.13 and 1.08, AR and asthma, respectively) and slightly decreased in males patients with AR. Those aged 20-39 years-old possessed the highest risk. A higher risk of developing brain cancer was found in patients with atopic diseases, and patient with AR or asthma also had an elevated risk of developing cancer of kidney and urinary bladder. In contrast, the risk of nonmelanoma skin cancer was lower in patients with AR and asthma. Compared to patients with only one atopic disease, those with more than one atopic disease had lower cancer risks. Our data suggests that the association between atopy and cancer is site-specific.

Malignancies after renal transplantation in Taiwan: a nationwide population-based study.

BACKGROUND: Renal transplantation has been regarded as the treatment of choice for end-stage renal disease. Renal transplantation increases the risk of cancers due to long-term immunosuppression. The types of post-transplantation malignancies may vary among different geographic regions and ethnic populations. To date, large population-based studies of post-transplantation malignancies in Asian renal transplant recipients (RTRs) have rarely been reported. METHODS: To investigate the patterns of post-transplantation malignancies in Chinese RTRs, we performed a nationwide population-based cohort study between 1997 and 2008 based on data from the National Health Insurance Database in Taiwan. Patterns of cancer incidence in RTRs were compared with those of the general population using standardized incidence ratios (SIRs). RESULTS: Among the 4716 RTRs (2475 males and 2241 females; mean age 44.1 ± 12.4 years) and 22 556 person-years of observation, 320 post-transplant cancers were diagnosed. The SIR of all cancers was 3.75 (95% confidence interval 3.36-4.18). Women had a higher risk than men for the development of malignancies (SIR 5.04 for women and SIR 2.88 for men). Renal, bladder and liver cancers were the most common cancers, with SIRs of 44.29, 42.89 and 5.07, respectively. When stratified by age, RTRs of young age at transplant (<20 years) had the highest risk of post-transplantation malignancies. CONCLUSIONS: This study demonstrates different patterns of malignancies after renal transplantation in Chinese RTRs, with higher incidences of kidney and bladder cancers. Physicians should be more vigilant in examining RTRs for post-transplantation malignancies especially in younger patients.

The risk of cancer in patients with psoriasis: a population-based cohort study in Taiwan.

BACKGROUND: An association between psoriasis and malignancy has been explored. However, no studies have been reported regarding cancer risk in Asian psoriasis populations. OBJECTIVES: The aim of this study was to investigate the risk of cancer development in association with psoriasis. The effects of age at diagnosis, treatment modalities, and observation time were also evaluated. METHODS: Data for this retrospective population-based cohort study were obtained from the Taiwan National Health Insurance Research Database (NHIRD). This study included 3,686 patients with first-time diagnosis of psoriasis between 1996 and 2000. Another 200,000 patients without psoriasis served as the comparison group. All enrolled subjects were followed-up until the end of 2007. Cumulative incidences and hazard ratios (HRs) of cancer development were determined. RESULTS: Among the 3,686 psoriasis patients, 116 had incident cancers. The 7-year cumulative incidence of cancer among psoriasis patients was 4.8%. The adjusted HR for developing a cancer in association with psoriasis was 1.66 (95% confidence interval [CI], 1.38-2.00). Cancer risk was higher in male patients than in female patients (adjusted HR 1.86 vs.1.14, respectively). Certain cancers were significantly associated with psoriasis, including those of the urinary bladder and skin, followed by oropharynx/larynx, liver/gallbladder, and colon/rectum. Patients with psoriasis had an increased adjusted HR for cancer that varied by age. Younger patients with psoriasis tended to have the greatest risk of cancer. Finally, systemic phototherapy and oral medication did not significantly increase the risk of cancer. Phototherapy with UVB appeared to reduce the risk of cancer in psoriasis (adjusted HR, 0.52; 95% CI, 0.29-0.95; P = .03). LIMITATIONS: NHIRD did not contain information regarding severity of psoriasis, status of smoking, alcohol use, family history of cancer, or diet. Misclassification of disease cannot be ruled out in a registry-based database. CONCLUSIONS: Psoriasis carries an elevated risk of malignancies, especially in younger and in male patients. This effect is independent of systemic treatment for psoriasis. Finally, phototherapy with UVB did not increase, but rather reduced, the risk of cancer in psoriasis.

Elevated risk of second primary cancer in patients with cutaneous malignant melanoma: a nationwide cohort study in Taiwan.

BACKGROUND: It has been described that Caucasian patients with cutaneous malignant melanoma (CMM) are at an increased risk of developing second primary cancer. However, no large-scale study of second primary cancer in CMM patients has been conducted among Asians, who have distinctly different skin types. OBJECTIVE: We sought to access the risk of second primary cancer among CMM patients based on data from a nationwide database in Taiwan. METHODS: Utilizing the catastrophic illness database of Taiwan's National Health Insurance Research Database, we identified 2665 CMM patients without prior cancers in the period from 1997 to 2008. The standard incidence ratio (SIR) of each cancer was calculated. RESULTS: The mean age ± standard deviation at diagnosis of CMM was 62.2 ± 17.4 years. The mean annual incidence was 0.9 cases per 100,000 people. The overall cancer risk was elevated (SIR: 2.54), with younger patients having a higher risk. The risk remained elevated during the first five years after the CMM diagnosis. CMM patients had a higher risk of developing cancers of eye (SIR: 275.68), connective tissue (SIR: 43.45), brain (SIR: 21.03), and non-melanoma skin cancer (SIR: 17.71). CONCLUSION: CMM patients have a 2.54-fold risk of second primary cancer, with younger patients at increased risk. The risk remains elevated during the first five years after the diagnosis of CMM. The sites with highest risk of second primary cancer are eye, connective tissue, brain, and non-melanoma skin cancer.