Targeting cyclin-dependent kinases (CDKs) has recently emerged as a promising therapeutic approach against cancer. However, the anticancer mechanisms of different CDK inhibitors (CDKIs) are not well understood. Our recent study revealed that selective CDK4/6 inhibitors sensitize colorectal cancer (CRC) cells to therapy-induced apoptosis by inducing Death Receptor 5 (DR5) via the p53 family member p73. In this study, we investigated if this pathway is involved in anticancer effects of different CDKIs. We found that less-selective CDKIs, including flavopiridol, roscovitine, dinaciclib, and SNS-032, induced DR5 via p73-mediated transcriptional activation. The induction of DR5 by these CDKIs was mediated by dephosphorylation of p73 at Threonine 86 and p73 nuclear translocation. Knockdown of a common target of these CDKIs, including CDK1, 2, or 9, recapitulated p73-mediated DR5 induction. CDKIs strongly synergized with 5-fluorouracil (5-FU), the most commonly used CRC chemotherapy agent, in vitro and in vivo to promote growth suppression and apoptosis, which required DR5 and p73. Together, these findings indicate p73-mediated DR5 induction as a potential tumor suppressive mechanism and a critical target engaged by different CDKIs in potentiating therapy-induced apoptosis in CRC cells. These findings help better understand the anticancer mechanisms of CDKIs and may help facilitate their clinical development and applications in CRC.

Neoadjuvant chemotherapy (NAC) has been demonstrated effective in several tumours, but its benefit has not yet been elucidated in colorectal cancer, especially locally advanced colorectal cancer (LACRC).

Cryptococcal meningoencephalitis remains a global health threat with limited treatment options. Currently, the most effective treatment regimens are based on a combination therapy of flucytosine with either amphotericin B or fluconazole. Slow but steady progress is being made toward universal access to flucytosine-based therapies. The broadening access to flucytosine combination therapies will be accompanied by the need for microbiological methods that reliably determine strain susceptibility. This is especially true considering that flucytosine susceptibility can vary widely across clinical isolates. Identifying culture conditions that best represent the host environment are likely optimal and may even be required for accurately determining in vivo flucytosine susceptibility. Here, we report that culture conditions incorporating host-like concentrations of carbon dioxide (CO2) potentiated flucytosine susceptibilities across clinical isolates (10 of 11) that exhibited a range of MIC values under ambient growth conditions (2 to 8 μg/mL) by standard Clinical and Laboratory Standards Institute susceptibility testing. CO2 induced a dose-dependent increase in flucytosine susceptibility between 2- and 8-fold over standard conditions. The CO2-dependent increase in flucytosine susceptibility did not correspond to an increase in fluorouracil susceptibility, indicating a central role for flucytosine uptake through the cytosine permease in the presence of host-like CO2 concentrations. Indeed, the expression of the cytosine permease gene (FCY2) was induced 18- to 60-fold in the mouse lung environment. Therefore, the activity of flucytosine is likely to be very dependent upon host environment and may not be well represented by standard in vitro susceptibility testing. IMPORTANCE Cryptococcus neoformans causes life-threatening infections of the brain. The most effective treatment regimens are based on flucytosine-based combination therapy, which has led to increasingly successful broadening of access to flucytosine globally. Wider use of flucytosine-based therapies for cryptococcal infections will require the ability to reliably determine clinical isolate susceptibilities. We showed that host-like carbon dioxide stress affected flucytosine susceptibility, and this likely occurred through flucytosine uptake. We further showed that the gene encoding the permease, FCY2, and that is responsible for flucytosine uptake was strongly induced during cryptococcal infection. Our data provide insights into the distinctions between the activity of flucytosine in the host environment and during in vitro susceptibility testing.

Background: Tumor stem cells (TSCs) have been widely reported to play a critical role in tumor progression and metastasis. We explored the role of tumor stemness in intrahepatic cholangiocarcinoma (iCCA) and established a prognostic risk model related to tumor stemness for prognosis prediction and clinical treatment guidance in iCCA patients. Materials and Methods: The expression profiles of iCCA samples (E-MTAB-6389 and GSE107943 cohorts) were used in the study. One-class logistic regression algorithm calculated the mRNA stemness index (mRNAsi). The mRNAsi-related genes were used as a basis for the identification of mRNAsi-related molecular subtypes through consensus clustering. The immune characteristics and biological pathways of different subtypes were assessed. The mRNAsi-related risk model was constructed with differentially expressed genes (DEGs) between subtypes. Results: The patients with high mRNAsi had longer overall survival than that with low mRNAsi. Two subtypes were identified with that C2 had higher mRNAsi and better prognosis than C1. Tumor-related pathways such as TGF-β and epithelial-mesenchymal transition (EMT) were activated in C1. C1 had higher enrichment of cancer-associated fibroblasts and tumor-associated macrophages, as well as higher immune response and angiogenesis score than C2. We screened a total 98 prognostic DEGs between C1 and C2. Based on the prognostic DEGs, we constructed a risk model containing three genes (ANO1, CD109, and CTNND2) that could divide iCCA samples into high- and low-risk groups. The two groups had distinct prognosis and immune characteristics. Notably, the risk score was negatively associated with mRNAsi (R = -0.53). High-risk group had higher enrichment score of T cell inflamed GEP, INF-γ, and cytolytic activity, and lower score of estimated IC50 of 5-fluorouracil and cisplatin than low-risk group. Conclusions: This study clarified the important role of tumor stemness in iCCA and developed an mRNAsi-related risk model for predicting the prognosis and supporting the clinical treatment in iCCA patients. The three genes (ANO1, CD109, and CTNND2) may serve as potential targets for iCCA treatment.

Brivudin, ((E)-5-(2-bromovinyl)-2'-deoxyuridine (BVDU) can be considered the gold standard for the treatment of varicella-zoster virus (VZV) infections, such as herpes zoster (shingles). It is available for clinical use in most European countries (except for the UK) and over the whole world (except for the US and Canada). Besides VZV its activity spectrum also includes various other herpesviruses, such as herpes simplex virus type 1 (HSV-1). Its activity against VZV and HSV-1 depends on phosphorylation by the virus-encoded thymidine kinase (TK). In its active form (BVDU TP or BVDU 5'-triphosphate), it can act as both substrate and inhibitor of the viral (i.e., HSV-1) DNA polymerase. It has proven to be effective against herpes zoster, including post-herpetic neuralgia (PHN). It is contra-indicated in patients concomitantly treated by 5-fluorouracil (FU), since its degradation product, (E)-5-(2-bromovinyl)uracil, is inhibitory to the catabolism of FU, which may enhance the toxicity of the latter. A new compound, the bicyclic nucleoside analogue (BCNA) Cf-1743, has been described, which is a more potent inhibitor of VZV replication than BVDU and which does not interfere with the catabolism of FU. It is applicable orally, as its 5'-valine ester FV-100 (Fermavir), but has not (yet) been marketed for clinical use.

Objective: To explore the application and efficacy of paclitaxel liposome in the treatment of advanced breast cancer among Chinese population in the real world. Methods: The clinical characteristics of patients with advanced breast cancer who received paclitaxel liposome as salvage treatment from January 1, 2016 to August 31, 2019 in 11 hospitals were collected and retrospectively analyzed. The primary outcome was progression free survival (PFS), and the secondary outcome included objective response rate (ORR) and safety. The survival curve was drawn by Kaplan-Meier analysis and the Cox regression model were used for the multivariate analysis. Results: Among 647 patients with advanced breast cancer who received paclitaxel liposome, the first-line treatment accounted for 43.3% (280/647), the second-line treatment accounted for 27.7% (179/647), and the third-line and above treatment accounted for 29.1% (188/647). The median dose of first-line and second-line treatment was 260 mg per cycle, and 240 mg in third line and above treatment. The median period of paclitaxel liposome alone and combined chemotherapy or targeted therapy is 4 cycles and 6 cycles, respectively. In the whole group, 167 patients (25.8%) were treated with paclitaxel liposome combined with capecitabine±trastuzumab (TX±H), 123 patients (19.0%) were treated with paclitaxel liposome alone (T), and 119 patients (18.4%) were treated with paclitaxel liposome combined with platinum ± trastuzumab (TP±H), 108 patients (16.7%) were treated with paclitaxel liposome combined with trastuzumab ± pertuzumab (TH±P). The median PFS of first-line and second-line patients (5.5 and 5.5 months, respectively) were longer than that of patients treated with third line and above (4.9 months, P<0.05); The ORR of the first line, second line, third line and above patients were 46.7%, 36.8% and 28.2%, respectively. Multivariate analysis showed that event-free survival (EFS) and the number of treatment lines were independent prognostic factors for PFS. The common adverse events were myelosuppression, gastrointestinal reactions, hand foot syndrome and abnormal liver function. Conclusion: Paclitaxel liposomes is widely used and has promising efficacy in multi-subtype advanced breast cancer.

Drug nano-carriers are crucial for achieving targeted treatment against cancer disorders with minimal side effects. In this study, a pH-responsive nanocomposite based on halloysite nanotube (HNT) coated with carboxymethyl cellulose (CMC)/polyethylene glycol (PEG) hydrogel for controlled delivery of 5-Fluorouracil (5-FU), a hydrophobic chemotherapy drug prescribed for different types of cancers was synthesized for the first time using the water-in-oil-in-water (W/O/W) technique. The developed CMC/PEG/HNT/5-FU nanocomposite was characterized by dynamic light scattering (DLS), zeta potential, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and Field emission scanning electron microscope (FE-SEM) to get information about the particle size, surface charge, interactions between functional groups, crystalline structure and morphology, respectively. High efficiencies in terms of drug entrapment and loading (46 % and 87 %, respectively) were attained. In-vitro drug release results revealed an improved and sustained 5-FU delivery in an acid environment compared to the physiological medium, corroborating the pH-sensitivity of the developed nano-carrier. Flow cytometry and MTT assays demonstrated that the 5-FU loaded nanocomposite had considerable cytotoxicity on MCF-7 breast cancer cells while it is not toxic against L929 fibroblast cells. The nanocomposite synthesized herein could serve as a platform for the pH-sensitive release of anti-cancer drugs.

Cellulose was extracted from mango fibers and subjected to acid hydrolysis to obtain a nanofiber. Two morphological structures based on the polylactic acid (PLA)/nanocellulose (NC) combination have been synthesized and Fe3O4 NPs (M) are incorporated into both combinations. The first formulation is obtained by blending technique (PLA/M-NC) and the second formulation is obtained by self-assembly of grafted copolymer (M-PLA-co-NC). The magnetic nanocomposites are used as carriers for 5-fluorouracil (5-FU), an anti-cancer drug, and curcumin (CUR) to get PLA/M-NC/5-FU/CUR and M-PLA-co-NC/5-FU/CUR. The structural, morphological, and magnetic properties of the obtained nanocomposites were characterized by various techniques. The loading, release of 5-FU/CUR and the inhibition efficacy of nanocarriers loaded drugs against bacteria, HePG-2, MCF-7, and HCT-116 cell lines were studied. The two morphological forms of nanocarriers are considered close in loading % of 5-FU; however, the M-PLA-co-NC nanocarrier loaded double the loading % of CUR into PLA/M-NC nanocarrier, revealing superiority of copolymeric micelle than the blended formulation. The dual drugs loaded magnetic copolymeric micelles M-PLA-co-NC/5-FU/CUR revealed slower release, higher antibacterial and antitumor efficacy than the PLA/M-NC/5-FU/CUR. In this respect, the M-PLA-co-NC/5-FU/CUR could be considered a good nanomedicine against Streptococcus, Bacillus subtilis, Klebsiella pneumonia and Escherichia coli bacteria, besides the investigated cell lines.

Extracellular vesicles (EVs) are nowadays a target of interest in cancer therapy as a successful drug delivering tool. Based on their many beneficial biocompatible properties are designed to transport nucleic acids, proteins, various nanomaterials or chemotherapeutics. Extracellular vesicles derived from mesenchymal stem/stromal cells (MSCs) possess their tumor-homing abilities. This inspired us to engineer the MSC's EVs to be packed with chemotherapeutic agents and deliver it as a Trojan horse directly into tumor cells. In our study, human dental pulp MSCs (DP-MSCs) were cultivated with gemcitabine (GCB), which led to its absorption by the cells and subsequent secretion of the drug out into conditioned media in EVs. Concentrated conditioned media containing small EVs (potentially exosomes) significantly inhibited the cell growth of pancreatic carcinoma cell lines in vitro. DP-MSCs were simultaneously engineered to express a suicide gene fused yeast cytosinedeaminase:uracilphosphoribosyltransferase (yCD::UPRT). The product of the suicide gene converts non-toxic prodrug 5-fluorocytosine (5-FC) to highly cytotoxic chemotherapeutic drug 5-fluorouracil (5-FU) in the recipient cancer cells. Conversion of 5-FC to 5-FU had an additional effect on cancer cell's growth inhibition. Our results showed a therapeutic potential for DP-MSC-EVs to be designed for successful delivering of chemotherapeutic drugs, together with prodrug suicide gene therapy system.

Polysaccharide-based magnetic nanocomposites can eminently illuminate several attractive features as anticancer drug carriers. In this study, rice straw-based cellulose nanowhisker (CNW) was used as solid support for Fe3O4 nanofillers to synthesize magnetic CNW. Then, cross-linked chitosan-coated magnetic CNW for 5-fluorouracil carrier abbreviated as CH/MCNW/5FU. Fourier-transform infrared, X-Ray diffraction, and X-ray photoelectron spectroscopy analysis indicated successful fabrication and multifunctional properties of the CH/MCNW/5FU nanocomposites. In addition, CH/MCNW/5FU nanocomposites showed hydrodynamic diameter and zeta potential value of 181.31 ± 3.46 nm and +23 ± 1.8 mV, respectively. Based on images of transmission electron microscopy, magnetic CNW as reinforcement was coated with chitosan to obtain almost spherical CH/MCNW/5FU nanocomposites with an average diameter of 37.16 ± 3.08. The nanocomposites indicated desired saturation magnetization and thermal stability, high drug encapsulation efficiency, and pH-dependent swelling and drug release performance. CH/MCNW/5FU nanocomposites showed potent killing effects against colorectal cancer cells in both 2D monolayer and 3D spheroid models. These findings suggest CH/MCNW as a potential carrier for anticancer drugs with high tumour-penetrating capacity.

Many locally advanced nasopharyngeal carcinoma patients develop local recurrence or distant metastasis. Our retrospective real-world study aims to evaluate the efficacy and safety of curative sequential approach with induction chemotherapy followed by concurrent chemoradiation + nimotuzumab as first-line therapy in advanced nasopharyngeal carcinoma. From 2015 to 2021, the clinic data of 117 patients with advanced nasopharyngeal carcinoma (stage III-IV a) who were treated in the Affiliated Hospital of Guangdong Medical University were retrospectively reviewed. Fifty-four patients in observation group received taxanes, cisplatin, and 5-fluorouracil/taxanes and cisplatin induction chemotherapy and nimotuzumab (200 mg, weekly) combined with concurrent chemo-radiotherapy (cisplatin: 40 mg/m2 weekly; intensity-modulated radiation therapy); 63 patients in control group received same therapy without nimotuzumab. There was no significant difference in patients' characteristic baseline between 2 groups (P > .05). The complete response rate and objective response rate of the observational group was significantly higher than control group (46.30% vs 17.64%, P = .01; 96.30% vs 82.54%, P = .02). The median follow-up time was 24.77 (3.53-65.97) months. Both of the median progress free survival time and overall survival time were not reached. The 5-year progression-free survival rate of observation group was greater than control group (84.40% vs 63.70%, hazard ratios 0.365, 95% confidence intervals 0.147-0.909, P = .03). The 5-year overall survival rate of observation group and control group were 91.70% and 84.60%, respectively (P = .20). None of the patients withdrew from the study due to adverse events. Nimotuzumab combined with concurrent chemoradiotherapy as first-line therapy in advanced nasopharyngeal carcinoma can improve objective response rate and 5-year progress free survival rate with good safety profile.

Odontogenic keratocyst (OKC) is an aggressive cystic lesion of the jaw with high growth and recurrence. Patients are usually asymptomatic and detected during routine radiographic examination. Management of OKC varies from conservative procedures like simple Enucleation and peripheral ostectomy to aggressive resection. More attention is given to new treatment protocols to form them simple and successful. 5 fluorouracil is an anti-metabolite used to treat basal cell carcinoma and other malignancies act by inhibiting thymidylate synthase an enzyme required for DNA synthesis causing cell death. This is a case report of a 40-year-old female patient with OKC treated with topical 5 fluorouracil after enucleation, has less morbidity minimal recurrence, and low cost.

Ginkgo biloba, as a medicinal plant in both traditional and western medicine, emerged as a potential therapeutic agent for the management of a variety of diseases, but ginkgo biflavones (bilobetin, isoginkgetin, and ginkgetin) application in cancer therapy and underlying mechanisms of action remained elusive. In the present study, we identified ginkgo biflavones as potential p53 activators that could enhance p53 protein expression level by inhibiting MDM2 protein expression. At the same time, they induced cell death independent of p53 transcriptional activity. Moreover, ginkgetin was a standout among ginkgo biflavones that reduced the survival of HCT-116 cells by induction of apoptosis and G2/M phase arrest. Furthermore, ginkgo biflavones induced ROS generation significantly, which resulted in ferroptosis. Finally, we provide evidence that ginkgetin strengthened the antitumor effect of fluorouracil (5-FU) in the HCT-116 colon cancer xenograft model. To sum up, ginkgo biflavones represent a new class of p53 activator that depends on the p53 wild-type status and warrants further exploration as potential anticancer agents.

Background: Studies confirmed that trastuzumab plus fluorouracil-based chemotherapy improves the survival to more than 1 year in human with human epidermal growth factor receptor-2 (HER2)-positive advanced gastric cancer. However, there are still a small proportion of patients who do not benefit from trastuzumab treatment. Case summary: Here, we described a case report of de novo trastuzumab resistance in HER2-positive gastric cancer. Concomitant cyclin-E1 (CCNE1) and HER2 amplification are associated with de novo trastuzumab resistance. Genomic analysis demonstrated CCNE1 amplification and TP53 mutation in a HER2-positive gastric cancer patient. This patient achieved significant survival benefit and good safety when the patient received triple regimens consisting of trastuzumab, apatinib, and camrelizumab. Conclusion: Trastuzumab plus camrelizumab plus apatinib has the potential efficacy in HER2-positive gastric cancer patients who were previously treated with trastuzumab plus chemotherapy. This may lead to a new solution to trastuzumab resistance.

Oral and intestinal mucositis are debilitating inflammatory diseases observed in cancer patients undergoing chemo-radiotherapy. These are devastating clinical conditions which often lead to treatment disruption affecting underlying malignancy management. Although alimentary tract mucositis involves the entire gastrointestinal tract, oral and intestinal mucositis are often studied independently utilizing distinct organ-specific pre-clinical models. This approach has however hindered the development of potentially effective whole-patient treatment strategies. We now characterize a murine model of alimentary tract mucositis using 5-Fluorouracil (5-FU). Mice were given 5-FU intravenously (50 mg/kg) or saline every 48 h for 2 weeks. Post initial injection, mice were monitored clinically for weight loss and diarrhea. The incidence and extent of oral mucositis was assessed macroscopically. Microscopical and histomorphometric analyses of the tongue and intestinal tissues were conducted at 3 interim time points during the experimental period. Repeated 5-FU treatment caused severe oral and intestinal atrophy, including morphological damage, accompanied by body weight loss and mild to moderate diarrhea in up to 77.8% of mice. Oral mucositis was clinically evident throughout the observation period in 88.98% of mice. Toluidine blue staining of the tongue revealed that the ulcer size peaked at day-14. In summary, we have developed a model reproducing the clinical and histologic features of both oral and intestinal mucositis, which may represent a useful in vivo pre-clinical model for the study of chemotherapy-induced alimentary tract mucositis and the development of preventative therapies.

5-Fluorouracil (5-FU) is one of the most widely used chemotherapeutic agents; however, it often causes intestinal mucositis with severe diarrhea. An efficient treatment strategy to reduce this side effect is lacking. Glutamate (Glu), a nonessential amino acid, is the most important energy source in the small intestine and has been shown to maintain intestinal morphology, barrier function, and antioxidative capacity. However, the effects of Glu on intestinal mucositis induced by chemotherapeutic agents have not been explored. This study aimed to demonstrate the alleviative effects of Glu on 5-FU-induced intestinal mucositis. Mucositis was induced in C57B/6N mice by intraperitoneal injection of 5-FU (50 mg/kg) for 6 days and assessed by histological and physiological analyses. Glu (500 or 1000 mg/kg) was orally administered as a pretreatment twice daily for 7 days before the initial treatment of 5-FU. Cellular proliferation and apoptosis were assessed using Ki-67 immunostaining and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, respectively. Furthermore, fluorescein isothiocyanate-dextran infiltration was assessed to measure intestinal permeability. In vitro experiments using rat intestinal epithelial cells (IEC-6 cells) were performed to clarify the effect of Glu on 5-FU-induced barrier dysfunction. Glu alleviated 5-FU-induced intestinal mucositis by reducing villi shortening, enhancing cell proliferation, and suppressing apoptosis. It also alleviated the 5-FU-induced increased intestinal permeability. In vitro studies revealed significantly increased trans-epithelial electrical resistance (TEER) in Glu-pretreated IEC-6 cells compared to that in 5-FU-treated and control cells. In conclusion, the findings of this study provide evidence for the potential of Glu to protect against 5-FU-induced intestinal mucositis in patients with cancer.

The current research relies on a one-pot green biosynthesis of silver nanoparticles (SNPs) with various ratios of silver (Ag) in the existence of N, N, N-trimethyl chitosan chloride (TMC) and carboxymethyl kappa-carrageenan (CMKC), to investigate the effectiveness of the synthesized silver nanocomposites (SNCs) as pH sensitive biodegradable carrier for orally intestinal delivery of 5-fluorouracil (5-FU) drug. FTIR, XRD, TEM and FE-SEM/EDX methods were utilized to demonstrate the structure of the prepared polyelectrolyte complex PEC (TMC/CMKC) and SNCs (TMC/CMKC/Ag). The results showed that the 5-FU encapsulation effectiveness inside all of the prepared SNCs samples was improved by increasing the concentration of Ag, reaching 92.16 ± 0.57 % with 3 % Ag. In vitro release behavior of 5-FU loaded SNC 3 % (TMC/CMKC/Ag 3 %), displayed slow and sustained release reaching 96.3 ± 0.81 % up to 24 h into pH 7.4 medium. The successful release of 5-FU from the loaded SNC 3 % was confirmed through occurrence of strong cytotoxicity, with an IC50 value of 31.15 μg/ml, and high % of apoptotic cells (30.66 %) within the treated HCT116 cells. Besides, SNC 3 % showed good biodegradability and antimicrobial properties against different bacterial strains. Overall, SNC 3 % can be suggested as an effective system for both controlled drug delivery and antibacterial action.

Numerous ocular toxicities that have been associated with the use of chemotherapeutic agents present as problems with the ocular surface, ocular adnexa, and lacrimal system, and many chemotherapeutic agents have tearing as a side effect. In this study, 34 eyes from 17 patients with a mean age of 62.4±14.8 years were analyzed. Chemotherapy was administered for a mean of 13.8±7.6 months. Chemotherapeutic agents of the following types were included: titanium silicate-1 (58.8%), Docetaxel (23.5%), Paclitaxel (11.8%), and 5-fluorouracil (5.9%). Tearing began 9.1 to 10.9 months after chemotherapy treatment. Within 3 months of beginning chemotherapy, tearing occurred in 9 patients (52.9%), and within 6 months, it occurred in 11 patients (64.7%). Mean tear break-up time was 5.4±2.6 sec. Ten eyes (29.4%) had normal fluorescein dye disappearance test findings (within grade 1), and the mean fluorescein dye disappearance test was 1.91±0.87. Among the 34 eyes, 24 (70.6%) had normal puncta and 9 (26.5%) and 1 (2.9%) had stenosis and blockage, respectively. Ten eyes (29.4%) showed total regurgitation, 19 eyes (55.9%) showed partial regurgitation, and 5 eyes (14.7%) showed no regurgitation upon syringing. Four eyes (11.8%) and 30 eyes (88.2%), respectively, showed soft and hard stops upon probing. Dacryoscintigraphy confirmed that 6 eyes (17.6%) were normal, 8 eyes (23.5%) showed post-sac delay or obstruction, and 20 eyes (58.8%) showed pre-sac delay or obstruction. The mean meiboscores for the upper and lower eyelids on LipiView were 2.15±0.86 and 2.53±0.79, respectively. The difference in meiboscores between the upper and lower eyelids was significant (P=0.004). Obstruction of the lacrimal drainage system is a significant contributing factor to tearing in chemotherapy patients. However, reflex tearing because of meibomian gland dysfunction should also be fully considered to effectively manage the tearing because of the high incidence of accompanying meibomian glands loss when the lacrimal drainage system is obstructed.

Individuals with skin of color represent a diverse population of racial and ethnic backgrounds, including but not limited to Black or African American, American Indian or Alaska Native, Asian American or Pacific Islander, Hispanic or Latino, and Middle Eastern or North African. Dermatologic health disparities exist in part because of systemic racism and are exacerbated by inadequate physician training and a lack of high-quality research on skin diagnoses that disproportionately affect people with skin of color. These conditions, which include postinflammatory hyperpigmentation, keloids, dermatosis papulosa nigra, pseudofolliculitis barbae, and acne keloidalis nuchae, are usually diagnosed clinically and not associated with an underlying systemic disease. They can have significant impacts on mental health and quality of life and are often underdiagnosed or undertreated in skin of color. Hydroquinone 4% is considered the standard treatment for postinflammatory hyperpigmentation. Standard treatment for keloids includes combination intralesional therapy with triamcinolone and fluorouracil. If treatment is preferred for dermatosis papulosa nigra, options include scissor excision, cryotherapy, curettage, electrodesiccation, and laser therapies. Shaving cessation is the best initial treatment for pseudofolliculitis barbae. Individuals with acne keloidalis nuchae should avoid frequent close shaves or short haircuts on the nuchal area of the scalp.