Loss of alcohol dehydrogenase 1B in cancer-associated fibroblasts: contribution to the increase of tumor-promoting IL-6 in colon cancer

BACKGROUND

Increases in IL-6 by cancer-associated fibroblasts (CAFs) contribute to colon cancer progression, but the mechanisms involved in the increase of this tumor-promoting cytokine are unknown. The aim of this study was to identify novel targets involved in the dysregulation of IL-6 expression by CAFs in colon cancer.

METHODS

Colonic normal (N), hyperplastic, tubular adenoma, adenocarcinoma tissues, and tissue-derived myo-/fibroblasts (MFs) were used in these studies.

RESULTS

Transcriptomic analysis demonstrated a striking decrease in alcohol dehydrogenase 1B (ADH1B) expression, a gene potentially involved in IL-6 dysregulation in CAFs. ADH1B expression was downregulated in approximately 50% of studied tubular adenomas and all T1-4 colon tumors, but not in hyperplastic polyps. ADH1B metabolizes alcohols, including retinol (RO), and is involved in the generation of all-trans retinoic acid (atRA). LPS-induced IL-6 production was inhibited by either RO or its byproduct atRA in N-MFs, but only atRA was effective in CAFs. Silencing ADH1B in N-MFs significantly upregulated LPS-induced IL-6 similar to those observed in CAFs and lead to the loss of RO inhibitory effect on inducible IL-6 expression.

CONCLUSION

Our data identify ADH1B as a novel potential mesenchymal tumor suppressor, which plays a critical role in ADH1B/retinoid-mediated regulation of tumor-promoting IL-6.

Post-transplant native pneumonectomy for interstitial fibrosis and small cell lung cancer

Lung transplantation is a definitive treatment for select patients with end-stage pulmonary disease. Following transplantation, the reported rate of lung cancer is between 1-9% and is associated with a variety of risk factors, including smoking history and chronic immunosuppression. The majority of post-transplant lung cancer reported in the literature is histologically classified as non-small cell lung carcinoma (NSCLC). We report a unique case of early stage small cell lung carcinoma (SCLC) identified in the native lung following single lung transplantation.

Muscle-specific deletion of SOCS3 does not reduce the anabolic response to leucine in a mouse model of acute inflammation

Excessive inflammation reduces skeletal muscle protein synthesis leading to wasting and weakness. The janus kinase/signal transducers and activators of transcription-3 (JAK/STAT3) pathway is important for the regulation of inflammatory signaling. As such, suppressor of cytokine signaling-3 (SOCS3), the negative regulator of JAK/STAT signaling, is thought to be important in the control of muscle homeostasis. We hypothesized that muscle-specific deletion of SOCS3 would impair the anabolic response to leucine during an inflammatory insult. Twelve week old (n=8 per group) SOCS3 muscle-specific knockout mice (SOCS3-MKO) and littermate controls (WT) were injected with lipopolysaccharide (LPS, 1mg/kg) or saline and were studied during fasted conditions or after receiving 0.5g/kg leucine 3h after the injection of LPS. Markers of inflammation, anabolic signaling, and protein synthesis were measured 4h after LPS injection. LPS injection robustly increased mRNA expression of inflammatory molecules (Socs3, Socs1, Il-6, Ccl2, Tnfα and Cd68). In muscles from SOCS3-MKO mice, the Socs3 mRNA response to LPS was significantly blunted (∼6-fold) while STAT3 Tyr705 phosphorylation was exacerbated (18-fold). Leucine administration increased protein synthesis in both WT (∼1.6-fold) and SOCS3-MKO mice (∼1.5-fold) compared to basal levels. LPS administration blunted this effect, but there were no differences between WT and SOCS3-MKO mice. Muscle-specific SOCS3 deletion did not alter the response of AKT, mTOR, S6 or 4EBP1 under any treatment conditions. Therefore, SOCS3 does not appear to mediate the early inflammatory or leucine-induced changes in protein synthesis in skeletal muscle.

End-of-radiation PSA as a novel prognostic factor in patients undergoing definitive radiation and androgen deprivation therapy for prostate cancer

Background

In men undergoing definitive radiation for prostate cancer, it is unclear whether early biochemical response can provide additional prognostic value beyond pre-treatment risk stratification.

Methods

Prostate cancer patients consecutively treated with definitive radiation at our institution by a single provider from 1993–2006 and who had an EOR PSA (n=688, median follow-up 11.2 years). We analyzed the association of an end-of-radiation (EOR) prostate-specific antigen (PSA) level, obtained during the last week of radiation, with survival outcomes. Multivariable-adjusted cox proportional hazards models were constructed to assess associations between a detectable EOR PSA (defined as ≥0.1 ng ml⁻¹) and biochemical failure-free survival (BFFS), metastasis-free survival (MFS), prostate cancer-specific survival (PCSS), and overall survival (OS). Kaplan-Meier survival curves were constructed, with stratification by EOR PSA.

Results

At the end of radiation, the PSA level was undetectable in 30% of patients. Men with a detectable EOR PSA experienced inferior 10-year BFFS (49.7% vs. 64.4%, p<0.001), 10-year MFS (84.8% vs. 92.0%, p=0.003), 10-year PCSS (94.3% vs. 98.2%, p=0.007), and 10-year OS (75.8% vs. 82.5%, p=0.01), as compared to men with an undetectable EOR PSA. Among NCCN intermediate- and high-risk men who were treated with definitive radiation and androgen deprivation therapy (ADT), a detectable EOR PSA was more strongly associated with PCSS than initial NCCN risk level (EOR PSA: HR 5.89, 95% CI 2.37–14.65, p<0.001; NCCN risk level: HR 2.01, 95% CI 0.74–5.42, p=0.168). Main study limitations are retrospective study design and associated biases.

Conclusions

EOR PSA was significantly associated with survival endpoints in men who received treated with definitive radiation and ADT. Whether the EOR PSA can be used to modulate treatment intensity merits further investigation.

Diagnosing musculoskeletal tumours: How accurate is CT-guided core needle biopsy?

INTRODUCTION

Biopsy is a critical juncture in the diagnostic process for evaluating musculoskeletal tumours. The traditional diagnostic standard of open biopsy yields highly accurate diagnoses but associated with it is a significant rate of procedural complications. Imaging-guided needle biopsy is now being widely adopted as a competitive and minimally-invasive alternative with significantly lower complication rates. We assess its diagnostic outcomes at a tertiary referral centre in Melbourne, Australia.

METHOD

Data pertaining to biopsy and surgical histology were retrieved from the musculoskeletal tumour database at St Vincent's Hospital, Fitzroy following approval from the Human Research Ethics Committee (HREC 091/13). Data analyses were performed in STATA 12 to assess diagnostic parameters and related outcomes.

RESULTS

Bone tumours (n = 380) yielded accuracy of 80.8% with diagnostic error of 7.1% and undiagnostic rates of 12.1%. Soft-tissue tumours (n = 751) yielded accuracy of 83.2% with diagnostic error of 10.5% and undiagnostic rates of 6.3%. Biopsy of benign tumours (n = 648, accuracy = 85.3%, error = 5.9%, undiagnostic 8.8%) was more accurate than malignant tumours (n = 501, accuracy = 75.8%, error 14.0%, undiagnostic 7.4%). The overall procedural complication rate was 0.7%.

DISCUSSION

CT-guided core needle biopsy is a safe, accurate, and highly effective procedure that obviates the need for open and surgical biopsy in a significant number of cases. When combined with fusion imaging, CT guidance is an accurate method of targeting specific regions of interest.

Hepatitis B inactive carriers: clinical course and outcomes

OBJECTIVE

Hepatitis B virus (HBV) inactive carriers are HBV e antigen (HBeAg)-negative patients with normal alanine aminotransferase (ALT) levels and HBV DNA of ≤ 10000 copies/mL. We aimed to determine the clinical impact of ALT and HBV DNA elevations during the course of HBV infection.

METHODS

From January 1989 to January 2012, 146 inactive carriers were prospectively followed every 6-12 months with ALT and HBV DNA measurements and with hepatocellular carcinoma (HCC) surveillance.

RESULTS

During the follow-up of 8 ± 6.3 years, 56 of the 146 patients maintained ALT ≤ 40 U/L and HBV DNA ≤ 10000 copies/mL. However, 39 had rises of ALT > 40-80 U/L and 4 had ALT > 80 U/L; all except one reverted to baseline values. Also, during follow up, 69 (47.3%) inactive carriers had increases in HBV DNA of > 10000-999999 copies/mL; 38 of these patients' HBV DNA returned to baseline levels, while the remaining 31 patients maintained elevated HBV DNA values but had corresponding ALT of ≤ 40 U/L. There were four liver-related outcomes: 129 (88.4%) remained "inactive carriers", 13 (8.9%) had loss of hepatitis B surface antigen (HBsAg), one (0.7%) had a spontaneous reactivation to HBeAg-negative chronic hepatitis, and two (1.4%) developed HCC.

CONCLUSIONS

Although the prognosis of inactive carrier is favorable, transient ALT and HBV DNA elevations may be observed but have minimal clinical significance. Moreover, continuous HCC surveillance remains necessary since the risk of development still exists.

Co-expression of the P75 neurotrophin receptor and neurotrophin receptor-interacting melanoma antigen homolog in the mature rat brain

The p75 neurotrophin receptor (p75(NTR)) is involved in the regulation of neuronal survival and phenotype, but its signal transduction mechanisms are poorly understood. Recent evidence has implicated the cytoplasmic protein NRAGE (neurotrophin receptor-interacting MAGE (from Melanoma AntiGEn) homolog) in p75(NTR) signaling. To gain further insight into the role of NRAGE, we investigated the co-expression of NRAGE and p75(NTR) in mature rat brain. In all areas examined, NRAGE appeared to be confined to neurons. In the basal forebrain cholinergic complex, NRAGE immunoreactivity was evident in all p75(NTR)-positive neurons. There were many more NRAGE-positive than p75(NTR)-positive neurons in these regions, however. NRAGE was also expressed in areas of the basal forebrain that did not express p75(NTR), including the lateral septal nucleus and the nucleus accumbens. A finding in marked contrast to previous studies was the presence of p75(NTR) immunoreactivity in neuronal cell bodies in the hippocampus. Hippocampal p75(NTR) immunoreactivity was apparent in rats 6 months and older, and was localized to the dentate gyrus and stratum oriens. All p75(NTR)-positive neurons in the dentate gyrus and hippocampal formation were positive for NRAGE. The majority of granular cells of the dentate gyrus and pyramidal cells in the hippocampal formation were positive for NRAGE and negative for p75(NTR). NRAGE was also present in some neuronal populations that express p75(NTR) after injury, including striatal cholinergic interneurons, and motor neurons. A region of marked disparity was the cerebral cortex, in which NRAGE immunoreactivity was widespread whereas p75(NTR) was absent. The results are consistent with an important role for NRAGE in p75(NTR) signaling, as all cells that expressed p75(NTR) also expressed NRAGE. The wider distribution of NRAGE expression suggests that NRAGE may also participate in other signaling processes.