The association between smoking and risk of skin cancer: a meta-analysis of cohort studies

The Increased Burden of Morbidity Over the Life-Course Among Patients with COPD: A Register-Based Cohort Study in Sweden

Purpose

Patients with a diagnosis of chronic obstructive pulmonary disease (COPD) often have other chronic disorders. This study aims to describe the life-course pattern of morbidity in patients with COPD.

Patients and Methods

Among all residents aged 50-90 years in Sweden in 1997, people with a hospital COPD diagnosis were identified using Swedish national registers (1997-2018). Each patient with COPD was matched by sex, birthyear and county of residency with up to five COPD-free controls. Other chronic disease diagnoses were identified during 1987-2018. Conditional logistic regression calculated risk of diseases diagnosed prior to first COPD diagnosis, producing odds ratios (OR) and 95% confidence intervals (95% CI). Cox regression estimated risk of diagnoses after first COPD diagnosis, producing hazard ratios (HR) and 95% CI.

Results

Among 2,706,814 individuals, 225,159 (8.3%) had COPD. The nested case-control sample included 223,945 COPD-cases with 1,062,731 controls. Prior to first COPD diagnosis, future COPD patients had higher risks than controls for most examined conditions. Highest risks were seen for chronic heart failure (OR = 3.25, 3.20-3.30), peripheral arterial disease (OR = 3.12, 3.06-3.18) and lung cancer (OR = 12.73, 12.12-13.37). Following the COPD diagnosis, individuals with COPD had higher risks of most conditions than individuals without COPD. Chronic heart failure (HR = 3.50, 3.46-3.53), osteoporosis (HR = 3.35, 3.30-3.42), depression (HR = 2.58, 2.53-2.64) and lung cancer (HR = 6.04, 5.90-6.18) predominated. The risk of vascular dementia was increased after COPD diagnosis (HR = 1.53, 1.48-1.58) but not Alzheimer's disease.

Conclusion

Accumulation of chronic morbidity may precede COPD. Following the diagnosis, an increased burden of cardiovascular disease and cancer is to be expected, but subsequent depression, osteoporosis, and vascular dementia should also be noted. Management strategies for patients with COPD should consider the higher-than-average risk of multimorbidity.

A Comprehensive Review of Various Therapeutic Strategies for the Management of Skin Cancer

Skin cancer (SC) poses a global threat to the healthcare system and is expected to increase significantly over the next two decades if not diagnosed at an early stage. Early diagnosis is crucial for successful treatment, as the disease becomes more challenging to cure as it progresses. However, identifying new drugs, achieving clinical success, and overcoming drug resistance remain significant challenges. To overcome these obstacles and provide effective treatment, it is crucial to understand the causes of skin cancer, how cells grow and divide, factors that affect cell growth, and how drug resistance occurs. In this review, we have explained various therapeutic approaches for SC treatment via ligands, targeted photosensitizers, natural and synthetic drugs for the treatment of SC, an epigenetic approach for management of melanoma, photodynamic therapy, and targeted therapy for BRAF-mutated melanoma. This article also provides a detailed summary of the various natural drugs that are effective in managing melanoma and reducing the occurrence of skin cancer at early stages and focuses on the current status and future prospects of various therapies available for the management of skin cancer.

Role of Insulin Use and Social Determinants of Health on Non-melanoma Skin Cancer: Results From the Behavioral Risk Factor Surveillance System

BACKGROUND

Non-melanoma skin cancer (NMSC) is a frequent type of malignancy with a steadily increasing incidence rate worldwide. Although NMSC was shown to be associated with diabetes, no studies have addressed the extent to which insulin use influences the risk of NMSC in light of social determinants of health (SDOH). We conducted a quantitative study that examined the interplay between insulin use, SDOH, additional covariates, and NMSC among individuals with diabetes.

METHODS

We based our analysis on the 2020 Behavioral Risk Factor Surveillance System (BRFSS), a national survey conducted yearly in the US. We performed weighted chi-squared test, logistic regression, and survival analyses on 8685 eligible participants with diabetes enrolled in the BRFSS.

RESULTS

Kaplan Meier survival curves showed higher probability of NMSC event-free survival for participants with diabetes using insulin compared to participants with diabetes not using insulin (log-rank test P < .001). Significant associations were detected between insulin use and reduced odds of NMSC (OR .56; 95% CI: .38-.82), and decreased hazard (HR .36; 95% CI: .21-.62), along with indices of SDOH.

CONCLUSIONS

Our findings suggest that socioeconomic differences related to the healthcare system and behavioral patterns are linked to discrepancies in the use of insulin and the development of NMSC.

Analysing the causal relationship between potentially protective and risk factors and cutaneous melanoma: A Mendelian randomization study

BACKGROUND

Previous observational studies reported altered melanoma risks in relation to many potential factors, such as coffee intake, smoking habits and photodamage-related conditions. Considering the susceptibility of epidemiological studies to residual confounders, there remains uncertainty about the actual causal roles of these reported factors in melanoma aetiology.

OBJECTIVES

This study aims to investigate the causal association between cutaneous melanoma (CM) and previously reported factors: coffee intake, alcohol consumption, lifetime smoking, socioeconomic status (SES), ease of skin tanning, childhood sunburn and facial ageing, providing insight into its underlying aetiology and preventative strategies.

METHODS

We utilized a two-sample MR analysis on data from the largest meta-analysis summary statistics of confirmed cutaneous melanoma including 30,134 patients. Genetic instrumental variables were constructed by identifying single nucleotide polymorphisms (SNPs) that associate with corresponding factors. Inverse variance weighted (IVW) was the primary MR method. For sensitivity and heterogeneity, MR Egger, weighted median, simple mode, weighted mode and MR Egger intercept tests were examined.

RESULTS

Cutaneous melanoma risks were found to be elevated in association with a predisposition towards ease of skin tanning (IVW: OR = 2.842, 95% CI 2.468-3.274, p < 0.001) and with childhood sunburn history (IVW: OR = 6.317, 95% CI 4.479-8.909, p < 0.001). Repeated MR after removing potential confounders and outliers demonstrated resolved horizontal pleiotropy and statistically significant results that closely mirrored the initial findings. Other potential factors, such as coffee intake, alcohol consumption, smoking and socioeconomic status (SES), indicated insignificant effects on melanoma risk in the analysis, and therefore, our Mendelian randomization study does not support their roles in modifying melanoma risks.

CONCLUSIONS

Our extensive MR analysis provides strong evidence of the causative role of ease of skin tanning and childhood sunburn history in elevating melanoma risk. Curtailing ultraviolet radiation (UVR) exposure may be the single best preventative strategy to reduce melanoma risk.

Bitter Phytochemicals as Novel Candidates for Skin Disease Treatment

Skin diseases represent a global healthcare challenge due to their rising incidence and substantial socio-economic burden. While biological, immunological, and targeted therapies have brought a revolution in improving quality of life and survival rates for certain dermatological conditions, there remains a stringent demand for new remedies. Nature has long served as an inspiration for drug development. Recent studies have identified bitter taste receptors (TAS2Rs) in both skin cell lines and human skin. Additionally, bitter natural compounds have shown promising benefits in addressing skin aging, wound healing, inflammatory skin conditions, and even skin cancer. Thus, TAS2Rs may represent a promising target in all these processes. In this review, we summarize evidence supporting the presence of TAS2Rs in the skin and emphasize their potential as drug targets for addressing skin aging, wound healing, inflammatory skin conditions, and skin carcinogenesis. To our knowledge, this is a pioneering work in connecting information on TAS2Rs expression in skin and skin cells with the impact of bitter phytochemicals on various beneficial effects related to skin disorders.

Systematic replication of smoking disease associations using survey responses and EHR data in the All of Us Research Program

OBJECTIVE

The All of Us Research Program (All of Us) aims to recruit over a million participants to further precision medicine. Essential to the verification of biobanks is a replication of known associations to establish validity. Here, we evaluated how well All of Us data replicated known cigarette smoking associations.

MATERIALS AND METHODS

We defined smoking exposure as follows: (1) an EHR Smoking exposure that used International Classification of Disease codes; (2) participant provided information (PPI) Ever Smoking; and, (3) PPI Current Smoking, both from the lifestyle survey. We performed a phenome-wide association study (PheWAS) for each smoking exposure measurement type. For each, we compared the effect sizes derived from the PheWAS to published meta-analyses that studied cigarette smoking from PubMed. We defined two levels of replication of meta-analyses: (1) nominally replicated: which required agreement of direction of effect size, and (2) fully replicated: which required overlap of confidence intervals.

RESULTS

PheWASes with EHR Smoking, PPI Ever Smoking, and PPI Current Smoking revealed 736, 492, and 639 phenome-wide significant associations, respectively. We identified 165 meta-analyses representing 99 distinct phenotypes that could be matched to EHR phenotypes. At P < .05, 74 were nominally replicated and 55 were fully replicated. At P < 2.68 × 10-5 (Bonferroni threshold), 58 were nominally replicated and 40 were fully replicated.

DISCUSSION

Most phenotypes found in published meta-analyses associated with smoking were nominally replicated in All of Us. Both survey and EHR definitions for smoking produced similar results.

CONCLUSION

This study demonstrated the feasibility of studying common exposures using All of Us data.

Skin Cancer and Hydrochlorothiazide: Novel Population-Based Analyses Considering Personal Risk Factors Including Race/Ethnicity

BACKGROUND

Hydrochlorothiazide, a common antihypertensive, has photosensitive properties, potentially increasing skin cancer risk. We evaluated melanoma and nonmelanoma skin cancer among hydrochlorothiazide users with 3 different cohorts as each allows assessment of different potential cofounders/effect modifiers, including race/ethnicity.

METHODS

We built 3 cohorts using IBM MarketScan Research Databases: Commercial and Encounters (>3.5 million individuals, 2010-2018), a subcohort with health risk assessment respondents (415, 330), and Medicaid (509, 767, 2011-2017). Adults (aged 18+ years) entered the respective cohort with a first-filled prescription (cohort entry) for hydrochlorothiazide (the exposure of interest) or angiotensin-converting enzyme (ACE) inhibitors (the active comparator), with ≥12 months of continuous enrollment with medical/pharmacy coverage at baseline. We excluded those who used hydrochlorothiazide/ACE inhibitor (including fixed-dose combination products) 12 months before cohort entry and those with prior skin cancer, HIV, or organ transplant. We compared the risk for hydrochlorothiazide versus ACE inhibitor using multivariate proportional hazards regression.

RESULTS

Baseline characteristics were similar, aside from more Black individuals among hydrochlorothiazide users (43.3% [95% CI, 43.0%-43.6%]) than ACE inhibitor users (28.1% [95% CI, 27.9%-28.3%]). The hazard ratio (95% CI) for nonmelanoma skin cancer related to hydrochlorothiazide (versus ACE inhibitor) was 0.96 (0.91-1.00) in the Commercial cohort, 1.01 (0.77-1.32) for the health risk assessment subcohort, and 1.33 (0.77-2.29) for Medicaid. For melanoma, the respective hazard ratios were 1.07 (0.95-1.20), 0.85 (0.43-1.67), and 0.93 (0.51-1.67), respectively.

CONCLUSIONS

Our evaluation using 3 different approaches, including adjustment for race/ethnicity, did not establish a clear difference between hydrochlorothiazide and ACE inhibitor in terms of skin cancer risk.

A registration trend in eyelid skin cancers and associated risk factors in Iran, 2005-2016

BACKGROUND

Eyelid skin cancers are the most prevalent ophthalmic malignancies. This study aimed to evaluate the association of the Human Development Index (HDI) and lifestyle risk factors with eyelid skin cancers in Iran.

METHODS

This ecological study analyzed the data collected from the Iranian National Population-based Cancer Registry (2005-2016). The data on provincial-level eyelid skin cancer risk factors were obtained from national sources. The association between provincial HDI and lifestyle risk factors with the prevalence of eyelid skin cancers was assessed.

RESULTS

The mean 12-year age-standardized incidence rate (ASIR) of eyelid skin cancers was 16.22 per 100,000 (9,104 cases). The overall ASIR showed an upward trend with an estimated annual average increase of 0.006 per year. There were positive correlations between the prevalence of overall eyelid skin cancers and provincial HDI, smoking, and obesity (r = 0.32, 0.42, and 0.37, respectively). In multivariate analysis, obesity/overweight remained a positive predictor for high prevalence of total eyelid skin cancers (OR = 1.97, 95%CI = 1.08-3.58, P = 0.026), carcinoma (2.10, 1.15-3.83, P = 0.015), and basal cell carcinoma (1.48, 0.99-2.20, P = 0.054).

CONCLUSIONS

An increasing trend in ASIR of eyelid skin cancers was observed in more than a decade in Iran which was positively associated with provincial HDI and prevalence of obesity. The findings of the study highlight the importance of promotional programs for preventing obesity/overweight and appropriate allocation of screening facilities based on the HDI level.

Skin cancer risk of menopausal hormone therapy in a Korean cohort

Conflicting studies exist on the association between menopausal hormone therapy (MHT) and skin cancers, such as melanoma and non-melanoma skin cancer (NMSC). This retrospective cohort study aimed to evaluate the risk of skin cancer from MHT using data from 2002 to 2019 from the National Health Insurance Service in South Korea. We included 192,202 patients with MHT and 494,343 healthy controls. Women > 40 years who had menopause between 2002 and 2011 were included. Patients with MHT had at least one MHT for at least 6 months and healthy controls had never been prescribed MHT agents. We measured the incidence of melanoma and NMSC. Melanoma developed in 70 (0.03%) patients with MHT and 249 (0.05%) controls, while the incidence of NMSC was 417 (0.22%) in the MHT group and 1680 (0.34%) in the controls. Tibolone (hazard ratio [HR] 0.812, 95% confidence interval [CI] 0.694-0.949) and combined oestrogen plus progestin by the manufacturer (COPM; HR 0.777, 95% CI 0.63-0.962) lowered the risk of NMSC, while other hormone groups did not change the risk. Overall, MHT was not associated with melanoma incidence in menopausal Korean women. Instead, tibolone and COPM were associated with a decrease in NMSC occurrence.

Carboxyhemoglobin (COHb): Unavoidable Bystander or Protective Player?

Carbon monoxide (CO) is a cytoprotective endogenous gas that is ubiquitously produced by the stress response enzyme heme-oxygenase. Being a gas, CO rapidly diffuses through tissues and binds to hemoglobin (Hb) increasing carboxyhemoglobin (COHb) levels. COHb can be formed in erythrocytes or in plasma from cell-free Hb. Herein, it is discussed as to whether endogenous COHb is an innocuous and inevitable metabolic waste product or not, and it is hypothesized that COHb has a biological role. In the present review, literature data are presented to support this hypothesis based on two main premises: (i) there is no direct correlation between COHb levels and CO toxicity, and (ii) COHb seems to have a direct cytoprotective and antioxidant role in erythrocytes and in hemorrhagic models in vivo. Moreover, CO is also an antioxidant by generating COHb, which protects against the pro-oxidant damaging effects of cell-free Hb. Up to now, COHb has been considered as a sink for both exogenous and endogenous CO generated during CO intoxication or heme metabolism, respectively. Hallmarking COHb as an important molecule with a biological (and eventually beneficial) role is a turning point in CO biology research, namely in CO intoxication and CO cytoprotection.

Skin Cancer Correlations in Psoriatic Patients

Psoriasis is a common chronic, immune-mediated, inflammatory disease with associated comorbidities. Common psoriasis-associated comorbidities include psoriatic arthritis, cardiovascular disease, metabolic syndrome, inflammatory digestive syndromes, and depression. A less studied association is between psoriasis and specific-site cancers. A key cell in the pathophysiology of psoriasis is the myeloid dendritic cell, which links the innate and adaptive immune systems, and therefore is involved in the control of cancer-prevention mechanisms. The relationship between cancer and inflammation is not new, with inflammation being recognized as a key element in the development of neoplastic foci. Infection leads to the development of local chronic inflammation, which further leads to the accumulation of inflammatory cells. Various phagocytes produce reactive oxygen species that cause mutations in cellular DNA and lead to the perpetuation of cells with altered genomes. Therefore, in inflammatory sites, there will be a multiplication of cells with damaged DNA, leading to tumor cells. Over the years, scientists have tried to assess the extent to which psoriasis can increase the risk of developing skin cancer. Our aim is to review the available data and present some information that might help both the patients and the care providers in properly managing psoriatic patients to prevent skin cancer development.

Cutaneous Squamous Cell Carcinoma in Immunocompromised Patients—A Comparison between Different Immunomodulating Conditions

Background: Immunosuppression is strongly associated with an increased risk of developing cutaneous squamous cell carcinoma (cSCC). Studies on solid organ transplant recipients (SOTR) and chronic lymphocytic leukemia (CLL) patients have already demonstrated higher rates of aggressive cSCC tumors in these populations compared to immunocompetent controls. Studies on other immunosuppressed patient groups are scarce. This study was aimed at assessing the effects of different immunomodulating conditions on patients diagnosed with cSCC. We sought to compare the clinical features, treatments, and survival rates among the different study groups, as well as outcomes to those of immunocompetent controls with cSCC. Methods: A retrospective analysis of 465 cSCC patients, both immunosuppressed (IS) and immunocompetent controls. Etiologies for immunosuppression included SOTR, CLL, chronic kidney disease (CKD), psoriasis, rheumatoid arthritis (RA) and systemic lupus erythematous (SLE). Results: Compared to the control group, IS patients demonstrated several significant differences. These include higher rates of positive resection margins, higher recurrence rates, and multiple SCC tumors. Patients in the IS group, who were also given immunomodulating agents, demonstrated even lower survival rates. Cox regression analysis demonstrated statistically significant decreased overall survival (OS) rates for IS patients compared to the controls (OR = 1.9, p = 0.031). SOTR patients tend to have multiple cSCC tumors (35%), with the highest number of primary tumors compared to controls (2.54 tumors per patient on average, p < 0.001), but also compared to all other IS groups. The average SCC lesion size in the SOTR group was the smallest, measuring at 13.5 mm, compared to the control group and all other IS groups. Decreased survival rates were seen on Cox regression analysis compared to controls (HR = 2.4, p = 0.001), but also to all other IS groups. CLL patients also had the highest rates of positive margins compared to controls (36% vs. 9%, p < 0.01) and to all other IS groups. They were also most likely to get adjuvant or definitive oncological treatments, either radiotherapy or chemotherapy, compared to controls (36% vs. 15%, p = 0.02) and to other IS groups. Patients in the CKD group demonstrated the highest rates for multiple cSCC (OR = 4.7, p = 0.001) and the worst rates of survival on Cox regression analysis (HR = 3.2, p = 0.001). Both rheumatoid arthritis and psoriasis patients demonstrated the shortest disease-free survival rates (2.9y ± 1.1, 2.3y ± 0.7, respectively), compared to controls (4.1y ± 2.8) and to all other IS groups. Conclusions: Among cSCC patients, immunosuppression due to SOTR, CLL, CKD, RA, and psoriasis is associated with worse outcomes compared to controls and other IS groups. These patients should be regarded as high-risk for developing aggressive cSCC tumors. This study is the first to assess and compare cSCC outcomes among multiple IS patient groups.

Skin cancer mortality in Spain: adjusted mortality rates by province and related risk factors

BACKGROUND

Ultraviolet radiation is the main environmental risk factor responsible for the development of skin cancer. Other occupational, socioeconomic, and environmental factors appear to be related to the risk of skin cancer. Furthermore, the factors appear to differ for melanoma and non-melanoma skin cancer (NMSC). The purpose of this study is to analyze mortality rates of skin cancer in the different provinces of Spain and to determine the influence of socioeconomic conditions and other environmental and demographic factors in rates.

METHODS

Deaths from melanoma and NMSC in the period 2000-2019 were obtained as well as socioeconomic and environmental variables. Annual standardized mortality rates (SMR) were calculated for all Spanish provinces. The Pearson correlation coefficient was calculated.

RESULTS

The SMR of melanoma was 2.10/100,000 inhabitants, while that of NMSC was 1.28/100,000. At the provincial level, a great variability is confirmed. Gross domestic product showed a positive correlation with melanoma mortality but a negative correlation with NMSC. Other environmental and socioeconomic variables also showed correlation, as a positive correlation between tobacco sales and melanoma and between agricultural development and the NMSC.

CONCLUSIONS

There are still important differences between each province that must be taken into account when planning health care and resource distribution. This ecological and province-wise study helps to elucidate the relationship between social and ambient exposure determinants and skin cancer mortality in Spain.

Frequency of skin cancer and evaluation of risk factors: A hospital-based study from Turkey

OBJECTIVES

Skin cancers are the most common type of cancer with a significantly increasing incidence. The purpose of the study was to uncover the one-year frequency of melanoma and non-melanoma skin cancers (NMSC) and to determine the risk factors in the development of skin cancer.

METHODS

The study included 7396 people from all age groups admitted to the dermatology clinic between October 2020 and 2021. The sociodemographic characteristics, sun protection habits, chronic diseases, and drug and vitamin use were evaluated. Lesions with clinical suspicion of skin cancer were excised.

RESULTS

The frequency of skin cancer was found to be 2.7%, basal cell cancer (BCC) 1.2%, squamous cell cancer (SCC) 1.1%, malignant melanoma (MM) was 0.4%. Daily black tea consumption was found to be a risk factor for three type of skin cancer, BCC (p = 0.021), SCC (p = 0.006), and MM (p = 0.002), respectively. Obesity was observed as a risk factor for BCC (p = 0.005) and MM (p = 0.008). We found that having a history of alcohol use were an independent risk factor for all skin cancer types and BMI <30 for SCC. Vitamin D and supplemental drugs intake were observed as protective factors for BCC (p = 0.035, p = 0.007, respectively). Daily coffee consumption was determined as a protective factor for SCC (p < 0.001) and MM (p = 0.049).

CONCLUSION

This study estimates the frequency of NMSC and melanoma. Also provides evidence to determine the risk factors and probably protective factors for the development of skin cancers.

Ear canal and middle-ear tumors: a single-institution series of 87 patients

BACKGROUND

Ear canal and middle ear tumors are rare and exhibit variability in histology and clinical manifestation. Surgical resection remains the treatment of choice, but individualized approach is needed to preserve function when possible.

AIMS/OBJECTIVES

To review the management and outcome of ear canal and middle ear tumors at an academic referral center.

MATERIALS AND METHODS

Helsinki University Hospital (HUS) patient files were searched for clinically and histologically confirmed ear canal and middle ear tumors over a 14-year period. The minimum follow-up time was 2 years.

RESULTS

Eighty-seven patients with 88 tumors were identified. There were 20 (23%) benign external auditory canal (EAC), 36 (41%) benign middle ear space (MES), 29 (33%) malignant EAC, and 3 (3%) malignant MES tumors. Most (92%) tumors were managed with primary resection. Thirty-five percent of the operatively managed patients had a residual or a recurrent tumor.

CONCLUSIONS AND SIGNIFICANCE

EAC and MES tumors show great diagnostic and histologic heterogeneity with need for individualized investigative and treatment approaches. In benign tumors, we advocate aggressive local surgical control without sacrificing vital structures. In malignant tumors, we recommend local surgical control with or without adjunct RT.

Tobacco Smoking and Liver Cancer Risk: Potential Avenues for Carcinogenesis

Smoking a cigarette generates over 4000 chemicals that have a deleterious impact on each part of the human body. It produces three main severe effects on the liver organ: oncogenic, immunological, and indirect or direct toxic effects. It results in the production of cytotoxic substances, which raises fibrosis and necro-inflammation. Additionally, it also directs the production of pro-inflammatory cytokines tumour necrosis factor alfa (TNF-α) and interleukins (IL-1β, IL-6) that will be responsible for the chronic liver injury. Furthermore, it gives rise to secondary polycythemia and successively raises the turnover and mass of red cells, which might be a common factor responsible for the development of oxidative stress in the liver due to iron overload. It also produces chemicals that are having oncogenic properties and raises the risk of liver cancer especially in sufferers of chronic hepatitis C. Smoking modulates both humoral and cell-mediated responses by restricting the proliferation of lymphocytes and inducing their apoptosis and ultimately decreasing the surveillance of cancer cells. Moreover, it has been determined that heavy smoking impacts the response of hepatitis C patients to interferon (IFN) therapy through different mechanisms, which can be improved by phlebotomy. Efforts are being made in different nations in decreasing the prevalence of smoking to improve premature death and ill effects of their nation's individuals.

The Role of p53 in Progression of Cutaneous Squamous Cell Carcinoma

Skin cancers are the most common types of cancer worldwide, and their incidence is increasing. Melanoma, basal cell carcinoma (BCC), and cutaneous squamous cell carcinoma (cSCC) are the three major types of skin cancer. Melanoma originates from melanocytes, whereas BCC and cSCC originate from epidermal keratinocytes and are therefore called keratinocyte carcinomas. Chronic exposure to ultraviolet radiation (UVR) is a common risk factor for skin cancers, but they differ with respect to oncogenic mutational profiles and alterations in cellular signaling pathways. cSCC is the most common metastatic skin cancer, and it is associated with poor prognosis in the advanced stage. An important early event in cSCC development is mutation of the TP53 gene and inactivation of the tumor suppressor function of the tumor protein 53 gene (TP53) in epidermal keratinocytes, which then leads to accumulation of additional oncogenic mutations. Additional genomic and proteomic alterations are required for the progression of premalignant lesion, actinic keratosis, to invasive and metastatic cSCC. Recently, the role of p53 in the invasion of cSCC has also been elucidated. In this review, the role of p53 in the progression of cSCC and as potential new therapeutic target for cSCC will be discussed.

Daily Lifestyle and Cutaneous Malignancies

Daily lifestyle is a fundamental part of human life and its influence accumulates daily in the human body. We observe that a good daily lifestyle has a beneficial impact on our health; however, the actual effects of individual daily lifestyle factors on human skin diseases, especially skin cancers, have not been summarized. In this review, we focused on the influence of daily lifestyle on the development of skin cancer and described the detailed molecular mechanisms of the development or regulation of cutaneous malignancies. Several daily lifestyle factors, such as circadian rhythm disruption, smoking, alcohol, fatty acids, dietary fiber, obesity, and ultraviolet light, are known to be associated with the risk of cutaneous malignancies, malignant melanoma, squamous cell carcinoma, basal cell carcinoma, and Merkel cell carcinoma. Although the influence of some daily lifestyles on the risk of skin cancers is controversial, this review provides us a better understanding of the relationship between daily lifestyle factors and skin cancers.

A brief history of carbon monoxide and its therapeutic origins

It is estimated that 10% of carbon throughout the cosmos is in the form of carbon monoxide (CO). Earth's earliest prebiotic atmosphere included the trinity of gasotransmitters CO, nitric oxide (NO), and hydrogen sulfide (H₂S), for which all of life has co-evolved with. The history of CO can be loosely traced to mythological and prehistoric origins with rudimentary understanding emerging in the middle ages. Ancient literature is focused on CO's deadly toxicity which is understandable in the context of our primitive relationship with coal and fire. Scientific inquiry into CO appears to have emerged throughout the 1700s followed by chemical and toxicological profiling throughout the 1800s. Despite CO's ghastly reputation, several of the 18th and 19th century scientists suggested a therapeutic application of CO. Since 2000, the fundamental understanding of CO as a deadly nuisance has undergone a paradigm shift such that CO is now recognized as a neurotransmitter and viable pharmaceutical candidate. This review is intended to provide a brief history on the trace origins pertaining to endogenous formation and therapeutic application of CO.