Voltage-gated sodium channels (VGSCs) play pivotal roles in cancer progression and have emerged as promising therapeutic targets and biomarkers. VGSCs comprise multiple subtypes with distinct tissue distributions, influencing tumour characteristics in different ways. Among these, the tetrodotoxin-sensitive α-subunits and the β1 subunit, commonly found in breast cancer, have been implicated in metastasis and tumour aggressiveness. The NaV1.5 channel and its neonatal variant (nNaV1.5) are overexpressed in aggressive cancers such as breast, prostate, colorectal, and lung cancers, thereby enhancing their invasive capacity. nNaV1.5 is particularly significant due to its tumour-specific expression and strong association with poor prognosis, especially in breast cancer, where it regulates cell proliferation, invasion, and tumour microenvironment remodelling. This review highlights nNaV1.5 as a critical ion channel that drives metastasis through ion regulation, extracellular acidification, and cytoskeletal remodelling. We further evaluate current therapeutic strategies, including siRNA, monoclonal antibodies, and small-molecule inhibitors, while addressing translational challenges such as tumour heterogeneity, drug delivery limitations, and off-target cardiotoxicity due to its similarity with the adult isoform. In addition, we explore the potential of nNaV1.5 as a biomarker subject to epigenetic regulations by factors including RE1-silencing transcription factor (REST) and histone deacetylase 2 (HDAC2), which may facilitate patient stratification and treatment optimization. By integrating mechanistic insights, therapeutic opportunities, and translational challenges, this review goes beyond descriptive summaries to provide a framework for advancing nNaV1.5 research from preclinical studies toward clinical application in cancer therapy.

CHARACTERISTICS OF SMEAR-POSITIVE PULMONARY TUBERCULOSIS WITH NORMAL CHEST RADIOGRAPHIC FINDINGS DURING A TUBERCULOSIS OUTBREAK IN NORTHEAST MALAYSIA: A CROSS-SECTIONAL STUDY Introduction: Tuberculosis (TB) remains a highly prevalent disease in Malaysia. Early identification using cost-effective methods such as chest radiography can reduce the health burden of a TB epidemic. However, normal chest radiographic findings are common. This study aimed to evaluate the characteristics of smear-positive pulmonary TB with normal chest radiographic findings during an outbreak. Methods: A cross-sectional study was conducted by reviewing the medical records of 56 pulmonary TB cases registered at Kodiang Health Clinic from April to October 2022. Smear-negative and extrapulmonary TB cases were excluded. Relevant information was extracted from the medical records and recorded in a case report form for data management and analysis. Results: Approximately 60.7% of the cases had symptoms lasting >2 weeks, and 89.3% showed abnormal findings upon clinical examination. Additionally, 73.2% had sputum acid-fast bacilli counts of ≥1+, and the sputum Mycobacterium tuberculosis culture and sensitivity test findings were positive in 82.1% of the cases. The proportion of smear-positive pulmonary TB with normal chest radiographic findings was 42.9%. The factors associated with smear-positive pulmonary TB with normal chest radiographic findings included being under 18 years old (P=0.021), being a student (P=0.010), being single (P=0.012) and being asymptomatic (P=0.04). Conclusion: Normal chest radiographic findings may lead to a misdiagnosis of smear-positive pulmonary TB, especially during an outbreak. Therefore, active case detection among close contacts with risk factors for normal radiographic findings should consider additional supportive tests.

Introduction: Upper respiratory tract infection (URTI) is commonly encountered at the primary care level. Its management is particularly challenging due to the similarity of its symptoms to coronavirus disease 2019 (COVID-19) infection. Our study evaluated the profiles and antibiotic use of patients seeking care from a dedicated community-based URTI clinic during the COVID-19 pandemic. Methods: A cross-sectional study was conducted. Data were obtained from the medical records of patients visiting the URTI clinic at the Alor Setar Primary Healthcare Centre between March and April 2020. Results: Overall, 587/4388 (13.3%) patients received treatment at the URTI clinic. Most patients were male (60.6%) and aged between 20 and 39 years (35.5%). Their most common symptoms were cough (68.4%), fever (31.6%), runny nose (24.6%), and sore throat (24.1%). Most patients were diagnosed with acute nasopharyngitis (52.5%), acute pharyngitis (18.6%), or acute tonsillitis (5.3%). The symptomatic medication prescription rate was 96.5%. Only 26 of the 435 patients diagnosed with URTI received antibiotics, yielding an antibiotic use rate of only 6.0% for URTI relative to overall drug use. Acute tonsillitis was more common in children <12 years old (p<0.001), while a cough and runny nose were more commonly indicative of acute nasopharyngitis than other conditions (p<0.001). Sore throat was more likely to be a symptom of acute pharyngitis (p<0.001) and acute tonsillitis (p<0.001). Conclusion Despite the challenges faced during the COVID-19 pandemic, the findings suggest that patients with URTI-like symptoms were properly managed, and the rate of antibiotic usage remained reasonable.
COVID-19 ; Primary Health Care ; Anti-Bacterial Agents