Voltage Gated Calcium Channels Negatively Regulate Protective Immunity to Mycobacterium tuberculosis

Mycobacterium tuberculosis modulates levels and activity of key intracellular second messengers to evade protective immune responses. Calcium release from voltage gated calcium channels (VGCC) regulates immune responses to pathogens. In this study, we investigated the roles of VGCC in regulating protective immunity to mycobacteria in vitro and in vivo. Inhibiting L-type or R-type VGCC in dendritic cells (DCs) either using antibodies or by siRNA increased calcium influx in an inositol 1,4,5-phosphate and calcium release calcium activated channel dependent mechanism that resulted in increased expression of genes favoring pro-inflammatory responses. Further, VGCC-blocked DCs activated T cells that in turn mediated killing of M. tuberculosis inside macrophages. Likewise, inhibiting VGCC in infected macrophages and PBMCs induced calcium influx, upregulated the expression of pro-inflammatory genes and resulted in enhanced killing of intracellular M. tuberculosis. Importantly, compared to healthy controls, PBMCs of tuberculosis patients expressed higher levels of both VGCC, which were significantly reduced following chemotherapy. Finally, blocking VGCC in vivo in M. tuberculosis infected mice using specific antibodies increased intracellular calcium and significantly reduced bacterial loads. These results indicate that L-type and R-type VGCC play a negative role in M. tuberculosis infection by regulating calcium mobilization in cells that determine protective immunity

Increased prevalence of testicular microlithiasis in men with familial testicular cancer and their relatives

Testicular germ cell tumours (TGCT) cluster in families, but responsible genes remain unidentified. The association between testicular microlithiasis (TM) and testicular carcinoma in situ (CIS) suggests that TM may be a TC risk factor. We report testicular ultrasound findings in men with familial TGCT (FTGCT) and their unaffected relatives. A total of 81 men (48 affected and 33 unaffected) from 31 families with ⩾2 TC cases underwent testicular ultrasound. Testicular microlithiasis was defined as either ‘classic' (⩾5 microliths) or ‘limited' (<5 microliths). Statistical analyses used Fisher's exact test and permutation testing. Testicular microlithiasis was more frequent in the contralateral testicles of men with a history of TGCT (affected men) than in unaffected men (48 vs 24%, P=0.04). The association appeared stronger for classic TM (21 vs 9%) than for limited TM (27 vs 15%). Testicular microlithiases were bilateral in six out of seven (87%) unaffected men. Among affected men, TM was not associated with histology, age at diagnosis or cancer treatment. Of the 31 families, 10 accounted for a majority (61%) of the TM cases identified (P=0.11). Testicular microlithiasis was more prevalent among FTGCT family members than described previously in the general population, and was more common among FTGCT cases vs unaffected blood relatives. Testicular microlithiasis appeared to cluster in certain families. These findings suggest both a familial predisposition to TM and an association between TM and FTGCT. If proven, this could be clinically important to men in FTGCT families, and may be useful in identifying specific genes involved in FTGCT

Carfilzomib-dexamethasone vs bortezomib-dexamethasone in relapsed or refractory multiple myeloma by cytogenetic risk in the phase 3 study ENDEAVOR

The randomized phase 3 study ENDEAVOR demonstrated a statistically significant and clinically meaningful improvement in progression-free survival (PFS) for carfilzomib and dexamethasone (Kd) vs bortezomib and dexamethasone (Vd) in relapsed or refractory multiple myeloma (MM). We conducted a preplanned subgroup analysis of ENDEAVOR to evaluate Kd vs Vd by cytogenetic risk. Of 785 patients with known cytogenetics, 210 (27%) had high-risk cytogenetics (Kd, n=97 [25%]; Vd, n=113 [28%]) and 575 (73%) had standard-risk cytogenetics (Kd, n=284 [75%]; Vd, n=291 [72%]). Median PFS in the high-risk group was 8.8 months for Kd vs 6.0 months for Vd (hazard ratio [HR], 0.65; 95% confidence interval [CI], 0.45-0.92; P=0.0075). Median PFS in the standard-risk group was not estimable for Kd vs 10.2 months for Vd (HR, 0.44; 95% CI, 0.33-0.58; P<0.0001). Overall response rates were 72.2% (Kd) vs 58.4% (Vd) in the high-risk group and 79.2% (Kd) vs 66.0% (Vd) in the standard-risk group. In the high-risk group, 15.5% (Kd) vs 4.4% (Vd) achieved a complete response (CR) or better. In the standard-risk group, 13.0% (Kd) vs 7.9% (Vd) achieved \u2a7eCR. This preplanned subgroup analysis found that Kd was superior to Vd in relapsed or refractory MM, regardless of cytogenetic risk.Leukemia accepted article preview online, 27 December 2016. doi:10.1038/leu.2016.390