High Bile Titer and High Bile to Serum Ratio of CYFRA 21 - 1 Reliably Discriminate Malignant Biliary Obstruction Caused by Cholangiocarcinoma.

INTRODUCTION: Previously we demonstrated that elevated serum CYFRA 21 - 1 is a reliable diagnostic and prognostic biomarker for biliary tract cancers. This study aims to explore the diagnostic performance of bile CYFRA 21 - 1 (bCYFRA 21 - 1) in discriminating malignant biliary obstruction (MBO) caused by cholangiocarcinoma (CCA). METHODS: 77 CCA patients ((17 intrahepatic CCA (iCCA), 49 perihilar CCA (pCCA) and 11 distal CCA (dCCA)) and 43 benign patients with biliary obstruction were enrolled. Serum and bile levels of CYFRA 21 - 1, carcinoembryonic antigen (CEA) and carbohydrate antigen 19 - 9 (CA19-9) were quantified. Diagnostic performances of these biomarkers were estimated by receiver operator characteristic curves. Subgroups analysis of these tumor markers among CCA subtypes was performed. RESULTS: High bCYFRA 21 - 1 (cut-off value of 59.25 ng/mL with sensitivity of 0.889 and specificity of 0.750) and high bile to serum ratio of CYFRA 21 - 1 (b/sCYFRA 21 - 1, cut-off value of 31.55 with sensitivity of 0.741 and specificity of 0.778) achieved better diagnostic performance than any other biomarker in discriminating MBO. Subgroup analysis revealed that bCYFRA 21 - 1 was significantly elevated in all CCA subtypes; moreover b/sCYFRA 21 - 1 was upregulated in pCCA and dCCA (the mean b/sCYFRA 21 - 1 of pCCA was highest among CCA subtypes: 57.90, IQR 29.82-112.27). CONCLUSIONS: Both high biliary CYFRA 21 - 1 and high bile to serum ratio of CYFRA 21 - 1 were reliable diagnostic biomarkers for MBO caused by CCA.

Gonadal Y-chromosome mosaicism with 45, X Turner syndrome complicated with bilateral HCG-secreting gonadoblastoma.

We report a rare case of bilateral HCG-secreting gonadoblastomas (Gb) in a 5.25-year-old girl of 45, X Turner syndrome (TS) with gonadal Y chromosome mosaicism. The clinical data were summarized, and the literatures were reviewed. The patient had enlarged breasts for 2 years and 3 months, with elevated ß-HCG of blood found for 8 months. The level of ß-HCG of cerebrospinal fluid, cranial MRI, chest and abdominal CT, and pelvic MRI were normal. After surgical gonad exploration, biopsy and excision, gonad venous blood hormone examination and SRY gene detection of gonad tissue, the diagnosis was confirmed as HCG-secreting Gb (bilateral) and TS (45, X) with gonad Y chromosome mosaicism. The patient received 4 courses of chemotherapy, and regular outpatient follow-up. At 9 months after gonadectomy, there was no clinical, laboratory, or radiological evidence of recurrence. We reported a nonclassical case of 45, X Turner syndrome (TS) with gonadal Y chromosome mosaicism, who presented with breast development as the first manifestation and then virilization due to bilateral HCG-secreting gonadoblastomas. Detection of serum ß-HCG and AFP is requisite for the diagnosis of precocious puberty, karyotyping is important for virilizing phenotypic female, and virilization in Turner syndrome implies the existence of Y chromosome(substance) (peripheral blood or tissue mosaicism) and the occurrence of gonadal tumors.

[Corrigendum] Screening of hub genes and evaluation of the growth regulatory role of CD44 in metastatic prostate cancer.

Subsequently to the publication of the above article, the authors have realized that they inadvertently included images of the same mice in Figs. 7A [the Negative Control (NC) experiment] and 8A [the 5B­3CT + Docetaxel (10 mg/kg) experiment]. After having consulted their original data, the authors have realized that these mice were correctly shown in the paper for the experiments portrayed in Fig. 7A; therefore, the corrected version of Fig. 8 is shown on the next page, showing the mice pertaining to the 5B­3CT + Docetaxel (10 mg/kg) experiment in Fig. 8A. The authors are grateful to the Editor of Oncology Reports for allowing them the opportunity to publish a Corrigendum, and all the authors agree to this Corrigendum. Furthermore, they apologize to the readership for any inconvenience caused. [Oncology Reports 46: 196, 2021; DOI: 10.3892/or.2021.8147].

Screening of hub genes and evaluation of the growth regulatory role of CD44 in metastatic prostate cancer.

Prostate cancer (PCa) is the most common cancer type in men worldwide. Currently, the management of metastatic PCa (mPCa) remains a challenge to urologists. The analysis of hub genes and pathways may facilitate the understanding of the molecular mechanism of PCa. In the present study, to identify the hub genes in the mPCa, the three datasets GSE3325, GSE6919 and GSE38241 were downloaded from the platform of the Gene Expression Omnibus and function enrichment analysis of differentially expressed genes (DEGs) was performed. A total of 168 DEGs were obtained and the DEGs were significantly enriched in 'cell junction' and 'cell adhesion', among others. The Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis demonstrated that DEGs were enriched in three pathways including 'focal adhesion', 'renal cell carcinoma' and 'Hippo signaling pathway'. The results of the protein­protein interaction network revealed that the hub genes in mPCa were separately PTEN, Rac GTPase­activating protein 1, protein regulator of cytokinesis 1, PDZ binding kinase, centromere­associated protein E, NUF2 component of NDC80 kinetochore complex, TPX2 microtubule nucleation factor, SOX2, CD44 and ubiquitin­like with PHD and ring finger domains 1. As a hub gene, CD44 was differentially expressed in PCa, as determined by Oncomine analysis. Further experiments in vivo demonstrated that SB­3CT, a selective matrix metalloproteinase inhibitor that has been reported to block CD44 cleavage and inhibit the downstream signaling pathway, suppressed the tumorigenicity of PCa cells by decreasing the expression levels of pyruvate dehydrogenase kinase 1 and 6­phosphofructo­2­kinase/fructose­2,6­biphosphatase 4. Moreover, the combination therapy with SB­3CT and docetaxel was more effective in inhibiting PCa compared with monotherapy. In conclusion, the identification of DEGs and the in vivo experimental results helped to elucidate the molecular mechanisms of PCa and provided a potential strategy for the treatment of PCa.

The metabolic role of PFKFB4 in androgen-independent growth in vitro and PFKFB4 expression in human prostate cancer tissue.

BACKGROUND: It is well known that androgen-deprivation therapy (ADT) can inevitably drive prostate cancer (PCa) cells into a castration-resistant state. According to the "Warburg effect", the metabolism of aggressive tumor cells increases significantly. The growth of cancer cells depends on glycolysis, which may be a potential target for cancer control. 6-Phosphofructo-2-kinase/fructose-2,6-biphosphatase 4 (PFKFB4) plays key roles in the proliferation and metastasis of PCa cells. However, there is very limited knowledge on the role of PFKFB4 in the conversion to castration resistance. The present study aimed to determine the changes in glucose consumption and PFKFB4 expression in LNCaP cells and androgen-independent LNCaP (LNCaP-AI) cells during the whole process of androgen-independent growth. Additionally, PFKFB4 expression in human PCa tissues was evaluated. METHODS: We established an androgen-independent LNCaP-AI cell line derived from LNCaP cells to mimic the traits of castration resistance in vitro. LNCaP-AI and LNCaP cells were cultured in the corresponding medium containing the same amount of glucose. At the end of experiments, the medium supernatant and blank medium were collected, and absorbance was measured. LNCaP-AI and LNCaP cells were harvested to detect PFKFB4 expression by Western blotting. Prostate tissue samples including PCa tissue, carcinoma-adjacent tissue and benign prostatic hyperplasia (BPH) tissue specimens were evaluated for PFKFB4 expression using immunohistochemistry. RESULTS: In 18 h supernatant samples, the glucose consumption and lactate secretion of LNCaP-AI cells were higher than those of LNCaP cells. The Western blot results indicated that PFKFB4 expression was increased in LNCaP-AI cells compared with LNCaP cells. Immunohistochemistry revealed that the expression of PFKFB4 in PCa tissue specimens was higher than that in BPH and adjacent tissue specimens. However, the differences in PCa tissue before and after ADT were not statistically significant. CONCLUSION: PFKFB4 may be associated with enhanced glycolysis during the androgen-independent growth of PCa cells in vitro. PFKFB4 may be a marker of PCa progression. Our results provide a rationale for further clinical investigation of PCa treatment focused on controlling PFKFB4 expression.

Cabin1 involves in renal tubular epithelial cells mitochondrial dysfunction through SIRT1/p53 pathway.

Background: Angiotensin II (AngII) induced Calcineurin binding protein 1 (Cabin1) protein expression significantly increased during Renal tubular epithelial cells (RTEC) injury. However, the detailed function of Cabin1 protein in RTEC was not characterized well. In this study, we aimed to explore the downstream target of Cabin1 in vitro model.Methods: Rat kidney epithelial cells were cultured and stimulated with AngII. Electron microscopy was performed to observe mitochondrial morphology change. Immunofluorescence staining was detected to observe the distribution of cytoskeleton and Cabin1. Mitochondrial morphology change and protein expression were detected by electrical microscopy and western blot.Results: AngII induced the disruption of cytoskeleton at 24 and 48 h. Western blot analysis showed AngII significantly induced the overexpression of Cabin1. AngII induced a great deal of small, long and irregular mitochondria in RTEC, aspect ratio which reflects the length-to-width ratio of mitochondria remarkably increased at 12 and 24 h. Knocking down Cabin1 aggravated mitochondrial morphological abnormality in AngII treated RTEC. In comparison with control, Cabin1, p53 and cyto C level were significantly increased in AngII treated cells, while SIRT1 level was obviously decreased. Knocked down Cabin1 plus AngII stimulated, SIRT1 was further decreased, while p53 and cyto C were significantly increased.Conclusions: Cabin1 involves in RTEC mitochondrial dysfunction through SIRT1/p53 pathway. Cabin1 may be used as a new marker for the mechanisms of RTEC injury.

Secreted Frizzled-Related Protein 2 Is Associated with Disease Progression and Poor Prognosis in Breast Cancer.

PURPOSE: Secreted frizzled-related protein 2 (sFRP2) is a secreted protein associated with cancer drug resistance and metastasis. However, few studies have reported serum sFRP2 levels in breast cancer. We evaluated serum sFRP2 as a potential biomarker for breast cancer. METHODS: Serum sFRP2 concentrations were detected in 274 breast cancer patients along with 147 normal healthy controls by enzyme-linked immunosorbent assay (ELISA). Diagnostic significance was evaluated by area under the curve (AUC) analysis and the Youden index. Prognostic significance was determined by Kaplan-Meier survival method and univariate and multivariate Cox proportional hazard regression model analyses. RESULTS: Serum sFRP2 was elevated in breast cancer patients compared to normal healthy controls (P < 0.001). The sensitivity of sFRP2 in diagnosing breast cancer was 76.9% at a specificity of 76.6%. Elevated serum sFRP2 levels are associated with primary tumor size, TNM stage, and lymph node metastases. The Kaplan-Meier curves showed a significant association of serum sFRP2 with progression-free survival. The multivariate Cox analysis confirmed that high serum sFRP2 was an independent prognostic factor for poor prognosis (HR = 3.89, 95% CI = 1.95-7.68, P = 0.001). CONCLUSIONS: In conclusion, serum sFRP2 may serve as a potential biomarker for breast cancer diagnosis and prognostic evaluation.

Upregulation of Cabin1 During Injury to Renal Tubular Epithelial Cells in Rats.

INTRODUCTION: Calcineurin-binding protein 1 (Cabin1) interacts with calcineurin and p53, but its function in renal tubular epithelial cell (RTEC) is unclear. We established 5/6 nephrectomized rats and angiotensin II-induced injury to the RTECs in vitro, to observe the expression of Cabin1 during RTEC injury. MATERIALS AND METHODS: Sprague-Dawley rats were sacrificed at 4 and 8 weeks after 5/6 nephrectomy. Renal pathology and mitochondrial damage were detected by light and electrical microscope. The distribution of E-cadherin and α-smad were detected by indirect immunofluorescence staining. Cabin1 protein expression was detected by Western blot. RESULTS: Obvious tubulointerstitial fibrosis was found in the nephrectomized rats at 8 weeks after 5/6 nephrectomy, accompanied by the increasing levels of creatinine, as well as the disruption of E-cadherin and overexpression of α-smad in RTECs. Moreover, the mitochondria became swollen and mitochondrial cristae were disrupted and poorly defined in the RTECs. Compared to the sham-operated rats, Cabin1 protein expression was significantly increased at 8 weeks after 5/6 nephrectomy, while angiotensin II-induced Cabin1 protein expression significantly increased 48 hours after stimulation in normal rat kidney epithelial cells. CONCLUSIONS: Injury to the RTEC and Cabin1 protein overexpression occurred in a time-dependent manner both in vitro and in vivo. Cabin1 may become a potential molecular target in RTEC injury.

CD44 regulates prostate cancer proliferation, invasion and migration via PDK1 and PFKFB4.

Our recent studies have shown that CD44, a cell-surface protein with functions in many biologic processes, involved in glucose metabolism of prostate cancer cells. However, the molecular mechanisms of the regulation need to be further elucidated. In present study, LNCaP cells infected with lentivirus vector overexpressing CD44. The expression levels of key enzymes in glucose metabolism known as PDK1 and PFKFB4 were determined using QRT-PCR and western blot. PDK1 and PFKFB4 in LNCaP and PC3 cells were knocked down with shRNA respectively, and then cell proliferation, invasion and cell migration assay were performed. We found that overexpression of CD44 increased expression levels of PDK1 and PFKFB4 in LNCaP cells. Silencing of PDK1 and PFKFB4 could decrease cell proliferation, inhibit invasion and migration ability of prostate cancer cells. In addition, CD44 inhibitor could decrease glucose consumption and increase ROS levels of PC-3 cells significantly, as well as sensitize PC-3 cells to docetaxel. Taken together, CD44 could modulate aggressive phenotype of prostate cancer cells, by regulation of the expression of PDK1 and PFKFB4. CD44 may be a novel potential therapeutic target.

Increased expression of ZEB1-AS1 correlates with higher histopathological grade and promotes tumorigenesis in bladder cancer.

Bladder cancer is one of the most common urinary cancers worldwide. Emerging studies indicated that long non-coding RNAs (lncRNAs) play crucial roles in cancer biology. In this study, we found that a novel lncRNA Zinc finger E-box-binding homeebox1 (ZEB1) antisense RNA (ZEB1-AS1) was overexpressed in bladder cancer tissues compared to paired noncancerous tissues. Moreover, the expression of ZEB1-AS1 was positive correlated with higher histological grade and TNM stage in bladder cancer. Furthermore, Loss-of-function experiments showed that down-regulation of ZEB1-AS1 not only can suppress cell growth but also can inhibit migration and induce apoptosis in bladder cancer cell lines 5637 and SW780. In conclusion, these findings indicated that ZEB1-AS1 plays regulatory roles in bladder cancer and it may become a novel molecular biomarker of prognosis and therapy in bladder cancer.

Elevated serum concentrations of HE4 as a novel biomarker of disease severity and renal fibrosis in kidney disease.

BACKGROUND: Human epididymis protein 4 (HE4), has recently been reported as a mediator of renal fibrosis. However, serum HE4 levels appear in a large number of patient samples with chronic kidney disease (CKD), and the relationship of these levels to disease severity and renal fibrosis is unknown. METHODS: In 427 patients at different stages of CKD excluding gynecologic cancer and 173 healthy subjects, serum HE4 concentrations were tested by chemiluminescent microparticle immunoassay. Renal biopsy was performed on 259 of 427 subjects. Histological findings were evaluated using standard immunohistochemistry. RESULTS: The levels of serum HE4 were higher in CKD patients than in healthy subjects, and higher levels were associated with more severe CKD stages. Patients with more severe renal fibrosis tended to have higher HE4 levels, and correlation analysis showed a significant correlation between HE4 and degree of renal fibrosis (r = 0.938, P < 0.0001). HE4 can be a predictor of renal fibrosis in CKD patients; the area under the receiver-operating characteristic curve (AUC-ROC) was 0.99, higher than the AUC-ROC of serum creatinine (0.89). CONCLUSION: Elevated levels of serum HE4 are associated with decreased kidney function, and also with an advanced stage of renal fibrosis, suggesting that HE4 may serve as a valuable clinical biomarker for renal fibrosis of CKD.

Value of serum human epididymis secretory protein 4 as a marker for differential diagnosis of malignant and benign gynecological diseases of patients in southern China.

BACKGROUND: This study investigated the clinical value of HE4 in distinguishing malignant and benign gynecological diseases of patients in southern China. METHODS: Preoperative serum CA125 and HE4 concentrations were tested in samples of women with malignant or benign gynecological diseases using fully automated methods (Abbott ARCHITECT) and validated cutoff values. RESULTS: For the discrimination of ovarian cancer from benign gynecological diseases, in premenopausal women, the sensitivity and specificity were 89.8% and 67.5% for CA125, 68.5% and 97.8% for HE4, and 88.9% and 78.6% for ROMA, whereas in postmenopausal women, the sensitivity and specificity were 86.6% and 88.9% for CA125, 57.3% and 100% for HE4, and 85.4% and 94.4% for ROMA. For the discrimination of endometrial cancer from benign gynecological diseases, in premenopausal women, the sensitivity and specificity were 20.3% and 67.5% for CA125, 56.8% and 97.8% for HE4, and 74.3% and 78.6% for ROMA, whereas in postmenopausal women, the sensitivity and specificity were 17.8% and 88.9% for CA125, 31.5% and 100% for HE4, and 32.9% and 94.4% for ROMA. CONCLUSIONS: We showed that HE4 had better specificity than CA125 in discriminating ovarian cancer, and endometrial cancer from benign gynecological diseases in southern China population.

Effect of the knockdown of Cabin1 on p53 in glomerular podocyte.

Calcineurin binding protein 1 (Cabin1) is a natural inhibitor of calcineurin (CN). Moreover, Cabin1 retards tumor cell apoptosis by regulating p53. This study was designed to observe the expression of Cabin1 during podocyte injury, as well as its relationship with p53. Sprague-Dawley rats were used for the establishment of 5/6 nephrectomized rat model. Sham-operated rats underwent ventral laparotomy without nephrectomy. Then, rats were sacrificed at 8 and 12 weeks after nephrectomy. WT-1, a podocyte nuclear protein, was used for indicating the localization of Cabin1 in glomeruli. As tacrolimus protects podocyte via inhibiting AngiotensinII (AngII) induced CN activation. Cultured podocytes were injured by AngII or restored by tacrolimus. The protein expression and localization was detected by western blot or immunofluorescence staining. Cabin1 was knocked down by siRNA in cultured podocytes. In 5/6 nephrectomized rats, the colocalization of Cabin1 and WT-1 became more obviously in podocyte nuclei. Cabin1 protein was markedly increased in rats at 8 and 12 weeks after nephrectomy, as well as in AngII injured podocytes at 48 h (0.99 ± 0.12 in AngII group versus 0.80 ± 0.16 in control group). Cabin1 and p53 colocalized in cultured podocyte nuclei, p53 expression was significantly decreased (0.21 ± 0.05 in siRNA group versus 0.31 ± 0.05 in negative control group) after Cabin1 was being knocked down. In conclusion, Cabin1 expression significantly increases during podocyte injury. Knockdown of Cabin1 induces p53 expression decrease in cultured podocyte. Cabin1 may provide a new target to investigate podocyte injury.

Cabin1 localizes in glomerular podocyte and undergoes nuclear translocation during podocyte injury.

CONTEXT: Podocyte injury is related to increasing proteinuria and contributes to the progression of kidney disease. Calcineurin binding protein 1 (Cabin1) is a repressor of myocyte enhancer factor 2 (MEF2) and calcineurin-mediated transcription in the immune system. Moreover, Cabin1 interacts with p53 and negatively regulates p53 in tumor cells. However, its function in kidney is unknown. OBJECTIVE: To explore the exact localization of Cabin1 in glomeruli, as well as the relationship between Cabin1 and podocyte injury. METHODS: Sprague-Dawley rats were sacrificed to observe the localization and protein expression of Cabin1 in the kidney. Cabin1 localization and protein expression were detected by immunofluorescence staining and western blot, respectively. Mouse podocytes were cultivated at 33 °C to propagate, then cells were transferred to an incubator at 37 °C to allow differentiation. Differentiated podocytes were stimulated by angiotensin II (AngII) or AngII plus tacrolimus. Cells were harvested to detect the localization and protein expression of Cabin1. Cytoplasmic and nuclear protein were separated by protein extraction kit. RESULTS: Cabin1 mainly localized in the nuclei of glomerular innate cells, it colocalized with WT-1 in podocytes nuclei. Western bolt showed Cabin1 protein remarkably expressed in renal cortex. AngII-induced Cabin1 nuclear protein significantly increased, accompanied by cytoskeleton disruption in cultured mouse podocytes. CONCLUSION: Cabin1 localizes in glomerular podocytes. AngII induces nuclear translocation of Cabin1 in cultured podocytes.

Phosphorylated signal transducer and activator of transcription 1 is a potential predictor of interferon response in patients with advanced renal cell carcinoma.

The present study aimed to evaluate the expression status of Janus kinase (JAK)-Signal Transducer and Activator of Transcription (STAT) in renal cell carcinoma and benign renal tissue, and identify a potential biomarker for interferon (IFN) response prediction. A total of 32 specimens of human renal cell carcinoma and 10 specimens of benign renal tissue were harvested from surgically removed kidneys. The expression levels of JAK­STAT were determined by immunohistochemical staining and quantitative polymerase chain reaction. Furthermore, the expression levels of JAK­STAT in renal cell carcinoma tissues that were stimulated with IFN-α were quantified by western blot analysis. The positive expression rates of JAK1, STAT1 and phosphorylated (P)­STAT1 in the renal cell carcinomas were significantly lower than that in the benign renal tissues (25.0, 31.2, and 12.5% vs. 70.0, 50.0, and 70.0%, respectively; P<0.05). The relative expression levels of JAK1 (0.696 ± 0.102) and STAT1 mRNA (0.341 ± 0.068) in the tumor tissue were lower than those in the benign tissue (0.957 ± 0.103 and 0.547 ± 0.082, respectively; P<0.05). IFN stimulation enhanced the expression levels of P­STAT1 in the renal cell carcinoma tissues, and enhancement of the P­STAT1 expression levels was associated with tumor relapse and metastasis. In conclusion, P­STAT1 is a potential predictor of IFN response in patients with advanced renal cell carcinoma.

[Relations of fetuin-A with estimated glomerular filtration rate and carotid artery calcification in patients with chronic kidney disease].

OBJECTIVE: To investigate the association of fetuin-A with residual renal function and carotid artery calcification in patients with chronic kidney disease (CKD). METHODS: Blood examples were collected form 60 CKD patients in stages CKD3 to CKD5 (20 patients per stage) for measurement of serum fetuin-A, albumin, calcium, phosphorus and parathyroid hormone, cholesterol, triglycercide, low-density lipoprotein, and high-density lipoprotein. MDRD equation was used to calculate the estimated glomerular filtration rate (eGFR), and ELISA was used to detect serum fetuin-A. Color Doppler ultrasound was performed to measure carotid intima-media thickness (CIMT). RESULTS: As the eGFR decreased, serum fetuin-A significantly decreased in CKD5 stage compared with that in CKD4 stage (P<0.05); compared with that in CKD3 stage, serum fetuin-A level was significantly lowered in CKD4 stage (P<0.05). Linear regression analysis suggested a significant positive correlation between fetuin-A and eGFR. The rate of carotid artery calcification was the highest in CKD5 stage. Rank correlation analysis showed a negative correlation between fetuin-A and cIMT, and logistic regression analysis identified decreased serum Fetuin-A as a risk factor of carotid artery calcification. CONCLUSION: Serum fetuin-A decreases following the decrease in eGFR, and decreased serum Fetuin-A level is a risk factor of carotid artery calcification in CKD patients.

Cigarette smoking has a positive and independent effect on testosterone levels.

Previous studies have suggested that testosterone levels are linked to a variety of diseases, such as cardiovascular disease, type-2 diabetes, the metabolic syndrome, erectile dysfunction, depression, stroke and osteoporosis. Since cigarette smoking is a major health problem and highly prevalent among men, several groups have studied the effects of cigarette smoking on testosterone levels in men. However, the results have been conflicting. Our objectives were to examine the association of cigarette smoking and serum levels of sex hormone-binding globulin (SHBG), total testosterone (TT) and free testosterone (FT) in a large male population. Data from 2,021 men (989 nonsmokers and 1,032 smokers), aged 20-69, were collected from the Fangchenggang Area Male Health and Examination survey using an in-person interview and self-administered questionnaires from September to December, 2009. We have found the following: (a) smokers had significantly higher TT and FT levels compared to nonsmokers, even after stratification as per age, BMI, triglycerides and alcohol consumption. (b) Both TT (r = -0.083, P <0.001) and FT (r = -0.271, P <0.001) levels were negatively correlated to the amount of tobacco exposure. (c) Smoking was an independent influencing factor for the levels of both TT (unadjusted OR = 1.64, 95% CI: 1.33-2.01, P <0.001; adjusted OR = 1.69, 95% CI: 1.34-2.13, P <0.001) and FT (unadjusted OR = 1.32, 95% CI: 1.08-1.61, P = 0.007; adjusted OR = 1.27, 95% CI: 1-1.61, P = 0.050) levels in multivariate logistic regression models before and after adjusting for age, BMI, fasting blood glucose, triglycerides, alcohol consumption and estradiol. (d) Smoking was not found to be an independent predictor of SHBG level after adjustment for confounders in multivariate regression model (P >0.05), although a positive association between increasing pack-years and SHBG level was observed (r = 0.174, P <0.001). More research is needed to elucidate the biological mechanisms and clinical significance of these associations.