Genomic analyses identify hundreds of variants associated with age at menarche and support a role for puberty timing in cancer risk

The timing of puberty is a highly polygenic childhood trait that is epidemiologically associated with various adult diseases. Using 1000 Genomes Project-imputed genotype data in up to similar to 370,000 women, we identify 389 independent signals (P <5 x 10(-8)) for age at menarche, a milestone in female pubertal development. In Icelandic data, these signals explain similar to 7.4% of the population variance in age at menarche, corresponding to similar to 25% of the estimated heritability. We implicate similar to 250 genes via coding variation or associated expression, demonstrating significant enrichment in neural tissues. Rare variants near the imprinted genes MKRN3 and DLK1 were identified, exhibiting large effects when paternally inherited. Mendelian randomization analyses suggest causal inverse associations, independent of body mass index (BMI), between puberty timing and risks for breast and endometrial cancers in women and prostate cancer in men. In aggregate, our findings highlight the complexity of the genetic regulation of puberty timing and support causal links with cancer susceptibility

Causal effect of plasminogen activator inhibitor type 1 on coronary heart disease

Background--Plasminogen activator inhibitor type 1 (PAI-1) plays an essential role in the fibrinolysis system and thrombosis. Population studies have reported that blood PAI-1 levels are associated with increased risk of coronary heart disease (CHD). However, it is unclear whether the association reflects a causal influence of PAI-1 on CHD risk. Methods and Results--To evaluate the association between PAI-1 and CHD, we applied a 3-step strategy. First, we investigated the observational association between PAI-1 and CHD incidence using a systematic review based on a literature search for PAI-1 and CHD studies. Second, we explored the causal association between PAI-1 and CHD using a Mendelian randomization approach using summary statistics from large genome-wide association studies. Finally, we explored the causal effect of PAI-1 on cardiovascular risk factors including metabolic and subclinical atherosclerosis measures. In the systematic meta-analysis, the highest quantile of blood PAI-1 level was associated with higher CHD risk comparing with the lowest quantile (odds ratio=2.17; 95% CI: 1.53, 3.07) in an age- and sex-adjusted model. The effect size was reduced in studies using a multivariable-adjusted model (odds ratio=1.46; 95% CI: 1.13, 1.88). The Mendelian randomization analyses suggested a causal effect of increased PAI-1 level on CHD risk (odds ratio=1.22 per unit increase of log-transformed PAI-1; 95% CI: 1.01, 1.47). In addition, we also detected a causal effect of PAI-1 on elevating blood glucose and high-density lipoprotein cholesterol. Conclusions--Our study indicates a causal effect of elevated PAI-1 level on CHD risk, which may be mediated by glucose dysfunction

Genomic analyses identify hundreds of variants associated with age at menarche and support a role for puberty timing in cancer risk

The timing of puberty is a highly polygenic childhood trait that is epidemiologically associated with various adult diseases. Using 1000 Genomes Project–imputed genotype data in up to ~370,000 women, we identify 389 independent signals (P < 5 × 10$^{−8}$) for age at menarche, a milestone in female pubertal development. In Icelandic data, these signals explain ~7.4% of the population variance in age at menarche, corresponding to ~25% of the estimated heritability. We implicate ~250 genes via coding variation or associated expression, demonstrating significant enrichment in neural tissues. Rare variants near the imprinted genes MKRN3 and DLK1 were identified, exhibiting large effects when paternally inherited. Mendelian randomization analyses suggest causal inverse associations, independent of body mass index (BMI), between puberty timing and risks for breast and endometrial cancers in women and prostate cancer in men. In aggregate, our findings highlight the complexity of the genetic regulation of puberty timing and support causal links with cancer susceptibility

Renal Cell Carcinoma in End-Stage Renal Disease: A Review and Update

Renal cell carcinoma (RCC) occurring in the setting of end-stage renal disease (ESRD) shows unique clinicopathological characteristics. The two most frequent types of ESRD-associated RCC are acquired cystic kidney disease-associated renal cell carcinoma (ACKD-RCC) and clear-cell papillary renal cell carcinoma (ccpRCC). Other types of RCC also occur in ESRD, albeit with different frequencies from the non-ESRD general population. The histological features of RCC do not vary in the setting of ESRD vs. non-ESRD, yet other findings, such as multifocality and multiple tumor types, are more frequent in ESRD. Studies have generated novel and important knowledge of the etiology, epidemiology, diagnosis, treatment, immunophenotype, and molecular characteristics of ESRD-associated RCC. Knowledge of these data is important for both pathologists and other physicians who may encounter ESRD patients with RCC. This review presents a comprehensive summary and update of the literature on RCC in ESRD, with a focus on the two most frequent types, ACKD-RCC and ccpRCC

Experimental chronic renal ischemia: Morphologic and immunologic studies

Although unilateral clamping of the renal artery to induce chronic ischemia of the kidney tissue has been utilized in several animal species, the resultant morphologic, ultrastructural and immunologic changes have never been well characterized. Moreover, the pathogenesis of these changes, as well as their roles in causing or facilitating the development of chronic tubulointerstitial nephritis have not been known. To examine some of these issues, male Sprague-Dawley rats were subjected to unilateral stenosis of the left main renal artery for 28 days. Stenotic and contralateral kidneys of experimental animals and kidneys from sham-operated controls were subjected to: (1) light microscopic, electron microscopic and immunofluorescent studies; (2) morphometric quantitation of the structural changes; (3) staining for actin, epithelial membrane antigen, keratin, and vimentin by immunoperoxidase technique; (4) staining for complex glycoproteins by a panel of 13 lectins; and (5) phenotyping and quantitation of the interstitial inflammatory infiltrates by monoclonal antibodies, using immunoperoxidase technique. The results reveal that: (1) The ischemic kidney tissue displays marked tubulointerstitial damages including abundant interstitial chronic inflammatory infiltrates, with good preservation of glomerular structure, which is consistent with the standard criteria of chronic tubulointerstitial nephritis. (2) The antigenic profile of the ischemic tubular epithelium displayed marked alterations including a neo-expression of vimentin and keratin, as well as a loss of endogenous avidin binding activity, Ia antigen and several complex surface glycoproteins detectable by lectins. (3) Neither electron dense deposits nor immunoglobulins are detectable in the kidneys from experimental or control animals. (4) Tubulitis, defined as infiltration of tubular epithelium by inflammatory cells, was present in up to 42.2% of tubular cross sections of the ischemic kidneys. (5) The interstitial inflammatory infiltrates were composed of B lymphocytes, T helper lymphocytes, and macrophages whereas the T non-helper lymphocytes were scanty, a phenotypic pattern similar to that of several other experimental rat models of chronic tubulointerstitial nephritis. It is concluded that: (1) In the Sprague-Dawley rats, ischemia alone can cause a constellation of changes fulfilling the accepted features of chronic interstitial nephritis; (2) ischemia alters the antigenic profile of the tubular epithelium and thereby may initiate a cell mediated immune response, accounting for the observed tubulitis and interstitial inflammation; and (3) ischemia may well be the final common pathway for chronic tubulointerstitial nephritis of diverse etiologies

Tubulointerstitial nephritis in systemic lupus erythematosus: innocent bystander or ominous presage

SLE-associated tubulointerstitial injury (SLE TIN) is increasingly recognized in two forms, i.e., secondary and primary. The secondary form coexists with lupus glomerulonephritis, whereas the primary form develops against the background of no or mild glomerular or vascular involvement. Secondary SLE TIN is frequent, but its frequency and severity correlate with the class of the associated lupus glomerulonephritis (GN), being almost universal in Class IV lupus GN and less frequent in GN of other classes. Although the presence of underlying GN may mask its clinical manifestation, secondary SLE TIN has a major prognostic implication for the renal outcome. Yet, SLE TIN is not factored in the current therapyfocused International Society of Nephrology/Renal Pathology Society schema of renal lupus classification, and its management remains to be elucidated. The pathogenesis of secondary SLE TIN is either immunologic, i.e., the tubulointerstitial injury being mediated by SLE-related immunologic mechanisms akin to those responsible for lupus GN; or non-immunologic, i.e., a nonspecific tubulointerstitial injury secondary to any type of advanced glomerular lesion, regardless of etiology. Primary SLE TIN is rare with about 15 reported cases. It has a rather uniform and distinctive clinical manifestation including acute kidney injury with no or mild proteinuria. It responds well to steroid and usually carries a good prognosis. Its pathogenesis is almost certain immunologic, with immunoglobulin/complement deposits along the tubular basement membrane in each reported case. In spite of these profound clinical implications, the current review underlies a limited knowledge on the pathobiology of SLE TIN