Rapid Increase of the Serum PSA Level in Response to High-Intensity Focused Ultrasound Therapy may be a Potential Indicator of Biochemical Recurrence of Low- and Intermediate-Risk Prostate Cancer

Objectives To determine the incidence and magnitude of the rapid increase in the serum PSA (riPSA) level after high-intensity focused ultrasound (HIFU) therapy for prostate cancer, and its correlation with clinical factors. Methods A total of 176 patients with localized prostate cancer underwent HIFU therapy. Serum riPSA was determined on the basis of the same criteria as those for “PSA bounce”, ie, an increase of ≥0.2 ng/ml with a spontaneous return to the prebounce level or lower. Patients were stratified according to neoadjuvant PSA level, T stage, risk group, age, Gleason score, pretreatment PSA level, post-treatment PSA nadir, and number of HIFU sessions. Results riPSA was seen in 53% of patients during a median follow-up period of 43 months. A PSA nadir was achieved within 3 months for 85.1% of the treatments. In all cases, onset of riPSA was seen two days after HIFU therapy, and the median magnitude was 23.69 ng/ml. A magnitude of >2 ng/ml was seen in 89.4% of cases. Univariate analysis revealed that patients with riPSA were associated with usage of hormonal therapy and the post-treatment PSA nadir level. Multivariate Cox regression analysis revealed that riPSA and the number of HIFU sessions were predictors of biochemical recurrence. A significant statistical association was found between the presence of riPSA and the risk of biochemical failure only in the low- and intermediate-risk group. Conclusion Patients treated with HIFU who experience post-treatment riPSA may have an increased risk of biochemical recurrence, especially in non-high-risk patients

Comparative lipidomics of 5-Fluorouracil-sensitive and -resistant colorectal cancer cells reveals altered sphingomyelin and ceramide controlled by acid sphingomyelinase (SMPD1).

5-Fluorouracil (5-FU) is a chemotherapeutic drug widely used to treat colorectal cancer. 5-FU is known to gradually lose its efficacy in treating colorectal cancer following the acquisition of resistance. We investigated the mechanism of 5-FU resistance using comprehensive lipidomic approaches. We performed lipidomic analysis on 5-FU-resistant (DLD-1/5-FU) and -sensitive (DLD-1) colorectal cancer cells using MALDI-MS and LC-MRM-MS. In particular, sphingomyelin (SM) species were significantly up-regulated in 5-FU-resistant cells in MALDI-TOF analysis. Further, we quantified sphingolipids including SM and Ceramide (Cer) using Multiple Reaction Monitoring (MRM), as they play a vital role in drug resistance. We found that 5-FU resistance in DLD-1/5-FU colorectal cancer cells was mainly associated with SM increase and Cer decrease, which are controlled by acid sphingomyelinase (SMPD1). In addition, reduction of SMPD1 expression was confirmed by LC-MRM-MS analysis and the effect of SMPD1 in drug resistance was assessed by treating DLD-1 cells with siRNA-SMPD1. Furthermore, clinical colorectal cancer data set analysis showed that down-regulation of SMPD1 was associated with resistance to chemotherapy regimens that include 5-FU. Thus, from our study, we propose that SM/Cer and SMPD1 are new potential target molecules for therapeutic strategies to overcome 5-FU resistance

CRISPR Screen Contributes to Novel Target Discovery in Prostate Cancer

Prostate cancer (PCa) is one of the common malignancies in male adults. Recent advances in omics technology, especially in next-generation sequencing, have increased the opportunity to identify genes that correlate with cancer diseases, including PCa. In addition, a genetic screen based on CRISPR/Cas9 technology has elucidated the mechanisms of cancer progression and drug resistance, which in turn has enabled the discovery of new targets as potential genes for new therapeutic targets. In the era of precision medicine, such knowledge is crucial for clinicians in their decision-making regarding patient treatment. In this review, we focus on how CRISPR screen for PCa performed to date has contributed to the identification of biologically critical and clinically relevant target genes

A Case of a Patient Who Successfully Achieved Early Wound Closure by Local Negative Pressure Wound Therapy (NPWT) against Compromised Wound Healing after Arterio-Venous Graft Infection

The primary treatment strategy for arterio-venous graft (AVG) infection includes appropriate antibiotic use and removal of the infected graft. It is well known that patients with hemodialysis are likely to experience compromised wound healing, which often leads to various postoperative complications. Negative pressure wound therapy (NPWT) is a non-invasive procedure that promotes wound healing by sealing the wound under negative pressure. Although NPWT is practically accepted in general surgery, there are only a few reports of this strategy to the vascular access operation for patients with hemodialysis due to the possibility of severe bleeding. In the present report, we report a case of a patient who successfully achieved safe and early wound closure by NPWT against compromised wound healing after AVG infection

Organ-Specific MicroRNAs (MIR122, 137, and 206) Contribute to Tissue Characteristics and Carcinogenesis by Regulating Pyruvate Kinase M1/2 (PKM) Expression

Pyruvate kinase is known as the glycolytic enzyme catalyzing the final step in glycolysis. In mammals, two different forms of it exist, i.e., pyruvate kinase M1/2 (PKM) and pyruvate kinase L/R (PKLR). Also, PKM has two isoforms, i.e., PKM1 and PKM2. These genes have tissue-specific distribution. Namely, PKM1 is distributed in high-energy-demanding organs, such as brain and muscle. Also, PKM2 is distributed in various other organs, such as the colon. On the other hand, PKLR is distributed in liver and red blood cells (RBCs). Interestingly, PKM2 has been recognized as one of the essential genes for the cancer-specific energy metabolism termed the “Warburg effect”. However, the mechanism(s) underlying this fact have remained largely unclear. Recently, we found that some organ-specific microRNAs (miRNAs, MIR) regulate PKM isoform expression through direct targeting of polypyrimidine tract binding protein 1 (PTBP1), which is the splicer responsible for PKM2-dominant expression. In this study, we examined whether this machinery was conserved in the case of other PTBP1- and PKM-targeting miRNAs. We focused on the MIRs 122, 137, and 206, and investigated the expression profiles of each of these miRNAs in tissues from mouse and human organs. Also, we examined the regulatory mechanisms of PKM isoform expression by testing each of these miRNAs in human cancer cell lines. Presently, we found that brain-specific MIR137 and muscle-specific MIR206 predominantly induced PKM1 expression through direct targeting of PTBP1. Also, liver-specific MIR122 suppressed the expression of both PKM1 and PKM2, which action occurred through direct targeting of PKM to enable the expression of PKLR. Moreover, the expression levels of these miRNAs were downregulated in cancer cells that had originated from these tissues, resulting in PKM2 dominance. Our results suggest that the organ-specific distribution of miRNAs is one of the principal means by which miRNA establishes characteristics of a tissue and that dysregulation of these miRNAs results in cancer development through a change in the ratio of PKM isoform expression. Also, our results contribute to cancer diagnosis and will be useful for cancer-specific therapy for the Warburg effect in the near future

SRSF3, a Splicer of the PKM Gene, Regulates Cell Growth and Maintenance of Cancer-Specific Energy Metabolism in Colon Cancer Cells

Serine and arginine rich splicing factor 3 (SRSF3), an SR-rich family protein, has an oncogenic function in various kinds of cancer. However, the detailed mechanism of the function had not been previously clarified. Here, we showed that the SRSF3 splicer regulated the expression profile of the pyruvate kinase, which is one of the rate-limiting enzymes in glycolysis. Most cancer cells express pyruvate kinase muscle 2 (PKM2) dominantly to maintain a glycolysis-dominant energy metabolism. Overexpression of SRSF3, as well as that of another splicer, polypyrimidine tract binding protein 1 (PTBP1) and heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1), in clinical cancer samples supported the notion that these proteins decreased the Pyruvate kinase muscle 1 (PKM1)/PKM2 ratio, which positively contributed to a glycolysis-dominant metabolism. The silencing of SRSF3 in human colon cancer cells induced a marked growth inhibition in both in vitro and in vivo experiments and caused an increase in the PKM1/PKM2 ratio, thus resulting in a metabolic shift from glycolysis to oxidative phosphorylation. At the same time, the silenced cells were induced to undergo autophagy. SRSF3 contributed to PKM mRNA splicing by co-operating with PTBP1 and hnRNPA1, which was validated by the results of RNP immunoprecipitation (RIP) and immunoprecipitation (IP) experiments. These findings altogether indicated that SRSF3 as a PKM splicer played a positive role in cancer-specific energy metabolism

Down-Grading of Ipsilateral Hydronephrosis by Neoadjuvant Chemotherapy Correlates with Favorable Oncological Outcomes in Patients Undergoing Radical Nephroureterectomy for Ureteral Carcinoma

Few studies have analyzed the details of neoadjuvant chemotherapy (NAC)-induced changes in patients with upper tract urothelial carcinoma. This study aimed to describe the impact of down-grading ipsilateral hydronephrosis by NAC for ureteral carcinoma. An observational study was conducted in 32 patients with cT1-3N0M0 ureteral carcinoma treated with NAC and radical nephroureterectomy. Hydronephrosis was classified into five grades based on computed tomography findings. We focused on the differences between the baseline and post-NAC status of ipsilateral hydronephrosis, radiographic tumor response, and blood markers. Down-grading, no change, and up-grading was observed in 10 (31%), 21 (66%), and 1 (3%) patients, respectively. In univariate analysis, locally advanced disease (cT3), severe hydronephrosis (grade 3/4) at baseline, no change/up-grading of hydronephrosis after NAC, and pathological lymphovascular involvement were identified as potential prognostic factors of progression-free and cancer-specific survival after radical nephroureterectomy. Locally advanced disease (cT3) at baseline and no change/up-grading of hydronephrosis by NAC were independently associated with poor progression-free survival. Notably, none of the patients with NAC-induced down-grading of hydronephrosis died of ureteral carcinoma during the follow-up. We reported the prognostic impact of down-grading of ipsilateral hydronephrosis, which could serve as a useful aid or clinical marker for decision-making

Comparison of Prognosis between Minimally Invasive and Abdominal Radical Hysterectomy for Patients with Early-Stage Cervical Cancer

Minimally invasive surgery (MIS) is performed to treat cervical cancer patients; however, a recent study showed that MIS was associated with higher recurrence and death rate compared with abdominal radical hysterectomy (ARH). In the current study, the prognosis of patients with early-stage cervical cancer who underwent MIS with vaginal closure or ARH was evaluated. One hundred and eighty-two patients underwent radical hysterectomy for cervical cancer with stage of IA2, IB1, and IIA1. MIS was performed by laparoscopy or a robot using the vaginal closure method. Disease-free survival (DFS) and overall survival (OS) were evaluated between the groups. Among the patients, 67 underwent MIS and 115 underwent ARH. The recurrence rate was 4.5% in MIS patients and 3.5% in ARH patients with a median follow-up (interquartile range) of 36 (18–60) and 78 (48–102) months, respectively. DFS and OS were not different between the groups (3y-DFS, 95.3% vs. 96.1%, p = 0.6; 3y-OS, 100% vs. 100%, p = 0.06). In early-stage cervical cancer patients, MIS with vaginal closure did not increase the risk for recurrence or death. Surgical techniques and procedures to avoid spillage of tumor cells could be important for a better prognosis