Downregulation of miR-506-3p Facilitates EGFR-TKI Resistance through Induction of Sonic Hedgehog Signaling in Non-Small-Cell Lung Cancer Cell Lines.

Non-small-cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutation eventually develop resistance to EGFR-targeted tyrosine kinase inhibitors (TKIs). Treatment resistance remains the primary obstacle to the successful treatment of NSCLC. Although drug resistance mechanisms have been studied extensively in NSCLC, the regulation of these mechanisms has not been completely understood. Recently, increasing numbers of microRNAs (miRNAs) are implicated in EGFR-TKI resistance, indicating that miRNAs may serve as novel targets and may hold promise as predictive biomarkers for anti-EGFR therapy. MicroRNA-506 (miR-506) has been identified as a tumor suppressor in many cancers, including lung cancer; however, the role of miR-506 in lung cancer chemoresistance has not yet been addressed. Here we report that miR-506-3p expression was markedly reduced in erlotinib-resistant (ER) cells. We identified Sonic Hedgehog (SHH) as a novel target of miR-506-3p, aberrantly activated in ER cells. The ectopic overexpression of miR-506-3p in ER cells downregulates SHH signaling, increases E-cadherin expression, and inhibits the expression of vimentin, thus counteracting the epithelial-mesenchymal transition (EMT)-mediated chemoresistance. Our results advanced our understanding of the molecular mechanisms underlying EGFR-TKI resistance and indicated that the miR-506/SHH axis might represent a novel therapeutic target for future EGFR mutated lung cancer treatment.

Beta-defensin index: A functional biomarker for oral cancer detection.

There is an unmet clinical need for a non-invasive and cost-effective test for oral squamous cell carcinoma (OSCC) that informs clinicians when a biopsy is warranted. Human beta-defensin 3 (hBD-3), an epithelial cell-derived anti-microbial peptide, is pro-tumorigenic and overexpressed in early-stage OSCC compared to hBD-2. We validate this expression dichotomy in carcinoma in situ and OSCC lesions using immunofluorescence microscopy and flow cytometry. The proportion of hBD-3/hBD-2 levels in non-invasively collected lesional cells compared to contralateral normal cells, obtained by ELISA, generates the beta-defensin index (BDI). Proof-of-principle and blinded discovery studies demonstrate that BDI discriminates OSCC from benign lesions. A multi-center validation study shows sensitivity and specificity values of 98.2% (95% confidence interval [CI] 90.3-99.9) and 82.6% (95% CI 68.6-92.2), respectively. A proof-of-principle study shows that BDI is adaptable to a point-of-care assay using microfluidics. We propose that BDI may fulfill a major unmet need in low-socioeconomic countries where pathology services are lacking.

Hepatitis B reactivation in cancer patients: role of prechemotherapy screening and antiviral prophylaxis.

Hepatitis B virus (HBV) infection is a potentially life-threatening condition that can be effectively prevented by vaccination. In the United States, more than 1.5 million people are infected with HBV, and that number continues to rise with the arrival of immigrants from HBV-endemic countries. Cancer is the second leading cause of death in the United States; 1 in 2 men and women will be diagnosed during their lifetime, and a large proportion of them will require chemotherapy. Chemotherapy-induced immunosuppression can result in HBV reactivation in asymptomatic HBV carriers or patients with resolved HBV infection, causing severe morbidity and mortality. The rate of HBV reactivation depends on several factors, including host and viral factors, and varies from 3-88%. Mortality rates in HBV reactivation range from 23-71%. However, a recent US survey showed that 20% of practicing oncologists never perform any type of HBV screening before the initiation of chemotherapy, and less than 40% perform HBV screening in patients who have high-risk factors for HBV or a history of hepatitis. Given the magnitude of this clinical problem, it is very important to increase awareness among physicians regarding this potentially life-threatening complication. In this article, we review the current understanding of the problem, discuss the existing guidelines from professional societies, and outline a management plan.

Outcomes of Daratumumab, Pomalidomide, and Dexamethasone, Followed by High-dose Chemotherapy and Autologous Stem Cell Transplantation, in Patients With Relapsed/Refractory Multiple Myeloma.

BACKGROUND: The number of therapeutic options for patients with relapsed/refractory multiple myeloma (RRMM) has increased significantly. Our institute treated a series of patients with RRMM using DPd (daratumumab, pomalidomide, dexamethasone) as salvage therapy, followed by high-dose chemotherapy (HDCT) and autologous stem cell transplantation (ASCT). PATIENTS AND METHODS: We treated 18 patients with RRMM from May 2016 to April 2020, with DPd as salvage therapy, followed by HDCT and ASCT. DPd was administered as daratumumab 16 mg/kg weekly for cycles 1 and 2, every 2 weeks for cycles 3 to 6, and then every 4 weeks. Pomalidomide was given at 4 mg orally on days 1 to 21 of a 28-day cycle, and dexamethasone at 20 or 40 mg weekly. RESULTS: The patients had received a median of 2 (range, 1-4) previous regimens. Of the 18 patients, 13 (72%) had received ASCT before this treatment. In addition, 78% had disease refractory to proteasome inhibitors, 78% refractory to immunomodulatory agents, and 72% double refractory to immunomodulatory agents and proteasome inhibitors. The overall response rate after salvage treatment with DPd was 100% and at day 100 after ASCT was 100%; 67% had achieved a complete response or better and 78% had achieved a very good partial response or better. No treatment-related mortality had occurred by day 100. The 2-year progression-free and overall survival rates were 83.3% and 94.4%, respectively. The most common grade ≥ 3 adverse events were thrombocytopenia (100%), neutropenia (100%), and neutropenic fever (67%). CONCLUSIONS: DPd as salvage therapy, followed by HDCT and ASCT, demonstrated deep, durable, and clinically meaningful responses with a manageable safety profile in patients with RRMM.

Unremitting chronic skin lesions: a case of delayed diagnosis of glucagonoma.

A 54-year-old Caucasian male with history of hypertension, hyperlipidemia, insulin-dependent diabetes mellitus, and chronic skin rash of 4 years presented to the emergency department with worsening rash and weight loss. Physical examination revealed diffuse erythematous rash, skin ulceration, bullae with associated paresthesia in the lower extremities, trunk, bilateral upper extremities, and palms and soles. A computed tomography (CT) scan with contrast showed a large, heterogenously enhancing pancreatic mass measuring 9.4 × 3.8 cm with surrounding low-attenuation soft tissue thickening. Blood tests showed hemoglobin A1C of 10.0%. Glucagon level was elevated to 2,178 (normal < 80 pg/dl). Endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) from the pancreatic mass was suggestive of pancreatic endocrine tumor. The tumor cells were positive for synaptophysin, chromogranin, CD56, and pan-cytokeratin with focal positivity for glucagon, suggestive of glucagonoma. The patient underwent distal pancreatectomy along with splenectomy and cholecystectomy. The glucagon level normalized to 25 pg/dl within a week of tumor resection, and during his 6-week outpatient follow up, skin rash had completely resolved.

Monitoring the Use of Telemonitor: A Resident-run Quality Improvement Initiative Decreases Inappropriate Use of Telemonitor in a Community Hospital.

Background Cardiac telemetry is an important tool to detect life-threatening conditions in hospitalized patients but is used widely and inappropriately. We sought to assess current usage and improve the appropriate use of telemetry in a community hospital. Methods We conducted a quality improvement project on patients who were admitted on telemetry floors between January and March 2017 (pre-intervention). The indication(s) and duration of telemonitor use, event(s) recorded on telemonitor and outcome of the event(s) were documented. A six-month educational intervention was undertaken and the effect of intervention was assessed among patients admitted between December 2017 and February 2018 (post-intervention). Results In the pre-intervention group, 329 patients qualified for the study, with a median age of 78 years. The post-intervention group had 383 qualified patients with a median age of 77 years. Mean duration of telemonitor use was four days in both groups. In the pre-intervention group, 54% had class I, 32% had class II, and 14% had class III indications. In post-intervention group, 46% had class I, 42% had class II, and 12% had class III indications. The educational intervention resulted in a trend towards less inappropriate use of telemetry, particularly in teaching service. Telemonitor events were recorded in 22 (7%) of the pre-intervention patients and 13 (4%) of the post-intervention group. Two patients died in the pre-intervention group and one in the post-intervention group from non-cardiac causes. Conclusion Our results highlight that change in practice requires sustained education interventions.

Digging deep into diabetes: achieving better glycemic control in diabetic patients in a resident-run clinic.

Background: Diabetes mellitus (DM) affects over 30 million Americans with an estimated annual cost of $327 billion in 2017. Patients with diabetes, especially with financial and/or social hardships, pose challenges in achieving target hemoglobin A1c (HbA1c) values. Understanding patient-specific barriers offer opportunities to improve outcomes in patient care. Objective: We aimed to improve a patient's glycemic control by reducing barriers to care. Furthermore, we evaluated the impact that a resident quality improvement effort had on providing high value diabetic care. Methods: We performed a retrospective cohort study of patients with HbA1c >9.0% in an underserved, resident-run clinic. Patients were surveyed on their knowledge of diabetes and reported obstacles to achieve diabetic control. We then implemented a 12 -month customized, patient-directed, multi-modal, multidisciplinary intervention. Results: Ninety-four patients with HbA1c >9.0% were identified, 65 surveyed, and 51 included in the intervention phase. After the intervention phase, re-evaluation of HbA1c in a paired sample comparison showed that the average HbA1c had decreased by 1.41% (11.28% vs. 9.87%, p < 0.01). Among the patients included in the intervention group, approximately 8% had their HbA1c reduced by ≥50% from their baseline, 23% had their HbA1c reduced by ≥25% from their baseline and 49% had their HbA1c reduced by ≥10% from their baseline. Conclusions: A strategically designed, a patient-centered customized intervention can have a positive impact on a patient's diabetic control.

An educational intervention to increase awareness reduces unnecessary laboratory testing in an internal medicine resident-run clinic.

At our resident-run clinic in an underserved community, laboratory test costs in 2013 exceeded the government subsidy by $400 000. To optimize limited resources and improve patient care, an education program to reduce testing was implemented. Between November 2014 and January 2015, residents attended lectures on utilization of laboratory testing, focusing on standard practice guidelines, and analyses of unnecessary tests. Multivariate nonparametric statistical methods and subgroup analysis were used to evaluate cost reduction. There were 453 clinic visits during the intervention period and 471 visits during the control period. Lectures were independently associated with a significant laboratory cost reduction. Median laboratory cost per visit decreased from $106.00 to $74.00. Total cost in the study period decreased from $79 403 to $51 463. There were similar reductions of laboratory costs in two subgroups: age groups of <50 years and ≥50 years, new encounters, and follow-up visits . In the analysis of individual tests, the cost of TSH and Vitamin D tests had the greatest reduction ($8176 and $5088 respectively). An appropriate physician education program can reduce laboratory tests and costs. Screening tests with inadequate evidence support were reduced most, whereas those with proven benefits did not decrease significantly.

Human papillomavirus oncogenic E6 protein regulates human ß-defensin 3 (hBD3) expression via the tumor suppressor protein p53.

Human ß-defensin-3 (hBD3) is an epithelial cell-derived innate immune regulatory molecule overexpressed in oral dysplastic lesions and fosters a tumor-promoting microenvironment. Expression of hBD3 is induced by the epidermal growth factor receptor signaling pathway. Here we describe a novel pathway through which the high-risk human papillomavirus type-16 (HPV-16) oncoprotein E6 induces hBD3 expression in mucosal keratinocytes. Ablation of E6 by siRNA induces the tumor suppressor p53 and diminishes hBD3 in HPV-16 positive CaSki cervical cancer cells and UM-SCC-104 head and neck cancer cells. Malignant cells in HPV-16-associated oropharyngeal cancer overexpress hBD3. HPV-16 E6 induces hBD3 mRNA expression, peptide production and gene promoter activity in mucosal keratinocytes. Reduction of cellular levels of p53 stimulates hBD3 expression, while activation of p53 by doxorubicin inhibits its expression in primary oral keratinocytes and CaSki cells, suggesting that p53 represses hBD3 expression. A p53 binding site in the hBD3 gene promoter has been identified by using electrophoretic mobility shift assays and chromatin immunoprecipitation (ChIP). In addition, the p63 protein isoform ΔNp63α, but not TAp63, stimulated transactivation of the hBD3 gene and was co-expressed with hBD3 in head and neck cancer specimens. Therefore, high-risk HPV E6 oncoproteins may stimulate hBD3 expression in tumor cells to facilitate tumorigenesis of HPV-associated head and neck cancer.

Identification and characterization of a cell-wall anchored DNase gene in Clostridium perfringens.

Completion of the whole genome sequence of Clostridium perfringens strain 13 revealed the presence of an extracellular nuclease gene, cadA. Transcriptional analysis showed that the cadA gene is negatively regulated by the two-component VirR/VirS system and its secondary regulator VR-RNA. The CadA protein possesses an N-terminal signal sequence and a Gram-positive cell wall anchoring motif consisting of a sorting signal (LPXTG motif), a hydrophobic domain, and positively charged residues at the end of C-terminus. By comparing the DNase production between the wild type and the cadA mutant, and DNase activity assay with the recombinant truncated CadA protein, we confirmed that the cadA gene product is one of the DNases produced by C. perfringens.

Atrial Papillary Fibroelastoma: A Stranger in a Strange Place.

Papillary fibroelastoma (PFE) is the most common primary tumor of cardiac valves and predominantly located on the left side. Its origin from non-valvular endocardium is extremely rare. We describe a case of an 81-year-old Caucasian male who presented with a mobile right atrial mass at the junction of right atrial wall and superior vena cava (SVC). Initially it was thought to be a thrombus and the patient was treated with anti-coagulation therapy without any change in size of the mass. Surgical excision was performed to establish the diagnosis and histopathology confirmed the diagnosis of PFE. In conclusion, this case is unique due to location of the tumor and its attachment with superior vena cava. Physicians should consider this unusual location of PFE in the differential diagnoses of an intra-atrial mass.

The VirR/VirS regulatory cascade affects transcription of plasmid-encoded putative virulence genes in Clostridium perfringens strain 13.

We analyzed the transcriptional regulation of the putative virulence genes encoded on the plasmid pCP13 from Clostridium perfringens strain 13. The transcription of the beta2-toxin (cpb2) and possible collagen adhesin (cna) genes were regulated in both a positive and negative manner, respectively, by the two-component VirR/VirS system. The secondary regulator of the VirR/VirS system, VR-RNA, also affects the expression of both of these genes in the same fashion as the VirR/VirS system. This indicates that the global regulatory cascade of the VirR/VirS system controls the expression of virulence genes located on the plasmid, as well as those found chromosomally in C. perfringens strain 13.

Organization and transcriptional regulation of myo-inositol operon in Clostridium perfringens.

myo-Inositol operon of Clostridium perfringens strain 13 consists of 13 genes with an upstream divergent regulator, iolR. Transcriptional analysis showed three separate transcripts for the operon of 15.6, 4.6 and 2.0 kb in length. iolR mutation studies showed that IolR is a negative regulator of the operon at transcriptional level. All the transcripts were induced by myo-Inositol in dose- and time-dependent manner. Glucose repressed the expression of all the transcripts of myo-Inositol operon. We also found that the operon was positively regulated by the two-component VirR/VirS system both in the presence and absence of myo-Inositol. This study shows that the global regulatory VirR/VirS system controls the expression of genes related to energy production (e.g. myo-Inositol operon) in addition to the virulence genes of C. perfringens strain 13.

Acute renal failure: a rare side effect of sunitinib therapy.

Sunitinib is an oral multiple tyrosine kinase receptor inhibitor. It is usually well tolerated but can cause fatigue, malaise, and rash. Sunitinib-induced cardiotoxicity has been well described, but nephrotoxicity is very rare. Here, we report a rare case of acute renal failure caused by sunitinib therapy in a 73-year-old Caucasian female who was enrolled in a phase II trial of sunitinib therapy for clear cell ovarian cancer. At presentation, her blood urea nitrogen (BUN) was 91 mg/dl and creatinine was 9.2 mg/dl. Sunitinib therapy was discontinued, and she was treated conservatively with intravenous fluid. Creatinine gradually returned to normal, and fatigue resolved. She was diagnosed with sunitinib-induced acute renal failure. The nephrologists and oncologists should be aware of sunitinib-induced rare nephrotoxicity, and patients should be closely monitored.

Constipation in Clostridium difficile infection.

A patient presented to our hospital with worsening shortness of breath, cough and respiratory distress that slowly worsened over 7-10 days. She had a viral-like illness with runny nose and cough for 1 week, which became productive of yellowish sputum. She was treated with antibiotic and steroid with clinical improvement. Her leucocyte count continued to increase despite discontinuation of both antibiotic and steroid. All culture results returned negative. She did not have any abdominal pain or diarrhoea. Her stool was positive for Clostridium difficile toxin assayed by PCR. A CT of abdomen showed distension of cecum and proximal colon. She was treated with intravenous metronidazole, oral and rectal vancomycin and intravenous immunoglobulin. She developed multi-organ failure and died.

Haematuria as an uncommon initial presenting symptom of metastatic squamous cell carcinoma (SCC) to kidney.

A 47-year-old female presented with a 2-week history of painless haematuria. Urine dipstick showed moderate leucocytes. Blood and urine cultures were negative and cytology was negative for malignant cells. Flexible cystoscopy was negative for any bladder pathology. An ultrasonogram of the abdomen showed a mass in the left kidney. CT showed a mass-like lesion within the left kidney suspicious for renal carcinoma, and cavitary lesions in both lungs. Biopsy of the lung showed clusters of atypical cells suspicious for squamous cell carcinoma (SCC), and left kidney lesion showed malignant cells derived from SCC. A whole body positron emission tomography/CT showed lesions in the lungs, left kidney and skeleton. Complete clinical examination, laboratory and imaging studies did not reveal any site of primary tumour in any part of the body. Haematuria is a very unusual initial presentation of metastatic tumour to kidney.

BOOP as a rare complication of gemcitabine therapy.

Gemcitabine is commonly used in combination with carboplatin in patients with advanced non-small-cell lung cancer (NSCLC). Gemcitabine has good clinical activity against NSCLC and is well tolerated by the patients. Myelosuppression is its dose-limiting toxicity. A potential side effect of gemcitabine is pulmonary toxicity. Among pulmonary toxicities, pneumonia, bronchospasm, acute respiratory distress syndrome, pleural effusion and interstitial pneumonitis are well documented, but bronchiolitis obliterans organising pneumonia (BOOP) is a rarely observed adverse effect of gemcitabine therapy. The authors report a female patient who presented with progressively worsening shortness of breath, low-grade fever and non-productive cough 10 days after completion of gemcitabine therapy for poorly differentiated invasive squamous cell carcinoma of lung with bone metastases. Histopathology of a transbronchial biopsy established the diagnosis of BOOP. Treatment with intravenous steroids resulted in prompt clinical improvement, but the patient later died of progression of her lung cancer.