High incidence of PI3K pathway gene mutations in South Indian cervical cancers.

INTRODUCTION: Cervical cancer is the second most common cancer in India. The phosphatidylinositol-3 kinase (PI3K) signaling is one of the most commonly activated pathways in cancer and comprises key molecules commonly targeted in cancer therapy. This study analyzed six PI3K pathway gene mutations. METHODS: We carried out targeted next-generation sequencing of six PI3K pathway genes (PIK3CA, PIK3R1, PTEN, AKT1, TSC2, and mTOR) in a total of 93 South Indian cervical cancer samples and confirmed them by sanger sequencing. RESULTS: The PI3K pathway gene mutations were observed in 54.8% (51/93) of the tumors and PIK3CA was the most mutated (34.4%, 32/93), followed by TSC2 (18.3%, 17/93), and PIK3R1 (14%, 13/93). The PIK3CA hotspot mutations E542K and E545K observed in this study were likely to disrupt the p110α-p85α interaction that could result in the PI3K pathway activation. We also found a few novel mutations in PIK3R1, PTEN, AKT1, TSC2, and mTOR genes while some of the tumors harbored multiple mutations in the genes of the PI3K pathway. The majority of the tumors were positive for high-risk HPV16/18 (60.7%). CONCLUSIONS: The high incidence of the PI3K pathway gene mutations observed in this study could be exploited for the therapeutic management of cervical cancers.

Linc-ROR genetic variants are associated with the advanced disease in oral squamous cell carcinoma.

OBJECTIVE: The objective of this study is to identify the association between linc-ROR genetic variants and oral squamous cell carcinoma tumorigenesis. DESIGN: Four genetic variants of linc-ROR (rs6420545, rs4801078, rs1942348, and rs9636089) were analyzed in 178 OSCCs and 191 controls of the South Indian population by PCR amplification followed by restriction digestion. In addition, we examined whether these variants alter linc-ROR expression levels and the progression of OSCC. RESULTS: The frequency of linc-ROR rs6420545 and rs4801078 genotypes were significantly associated with advanced tumor grade (>2) (p = 0.002 and p = 0.048), and nodal metastasis (p = 0.001 and p = 0.019), respectively. We observed a significant association of rs6420545 specifically in the over-dominant model [OR 1.77 (95%CI; 1.17-2.68); p = 0.006] and rs9636089 in dominant model [OR 2.17 (95%CI; 1.06 - 4.46); p = 0.03], and allelic model [OR 2.26 (95%CI; 1.13 - 4.53) p = 0.02], respectively. Further, significant upregulation of linc-ROR (p = 0.005) was observed in our cohort, consistent with the HNSCC TCGA dataset (p < 0.0001). CONCLUSIONS: Our findings suggest that the linc-ROR genetic variants could contribute to the metastasis and progression mainly in the late event of tumorigenesis of OSCCs and these variants could be useful in the precision therapeutic management of this cancer particularly in prognosis.

Genetic variant rs10251977 (G>A) in EGFR-AS1 modulates the expression of EGFR isoforms A and D.

Tyrosine kinase inhibitor is an effective chemo-therapeutic drug against tumors with deregulated EGFR pathway. Recently, a genetic variant rs10251977 (G>A) in exon 20 of EGFR reported to act as a prognostic marker for HNSCC. Genotyping of this polymorphism in oral cancer patients showed a similar frequency in cases and controls. EGFR-AS1 expressed significantly high level in tumors and EGFR-A isoform expression showed significant positive correlation (r = 0.6464, p < 0.0001) with reference to EGFR-AS1 expression levels, consistent with larger TCGA HNSCC tumor dataset. Our bioinformatic analysis showed enrichment of alternative splicing marks H3K36me3 and presence of intronic polyA sites spanning around exon 15a and 15b of EGFR facilitates skipping of exon 15b, thereby promoting the splicing of EGFR-A isoform. In addition, high level expression of PTBP1 and its binding site in EGFR and EGFR-AS1 enhances the expression of EGFR-A isoform (r = 0.7404, p < 0.0001) suggesting that EGFR-AS1 expression modulates the EGFR-A and D isoforms through alternative splicing. In addition, this polymorphism creates a binding site for miR-891b in EGFR-AS1 and may negatively regulate the EGFR-A. Collectively, our results suggested the presence of genetic variant in EGFR-AS1 modulates the expression of EGFR-D and A isoforms.

Managing cancer during COVID pandemic - Experience of a tertiary cancer care center.

OBJECTIVE: The COVID-19 pandemic has forced healthcare providers worldwide to bring in changes in the way cancer patients are cared for. Many cancer departments globally have brought in changes to their daily practice. This article is about our experience of evolving "COVID 19 PROTOCOL" devised in our department and taking a shape to suit a health care system with limited budget. MATERIALS AND METHODS: All the patient census & details of department of surgical oncology, Royapettah cancer hospital, from month of March 2020 to July 2020, who were subjected to COVID protocol were compared to patient census of similar duration in immediate past five months of October 2019 to February 2020. The data from out-patient department, ward in-patient census and healthcare personnel data was analyzed. RESULTS: There was a drop to 63.5% in OP census and 61.6% in IP census. There was a drop to 64.5% in number of major cases operated during initial phases of COVID pandemic. Health care workers were also infected with the COVID but cross infectivity can be checked if proper steps to adhere to an institutional protocol based on general measures of cleanliness are taken. CONCLUSION: Adherence to an institutional protocol based on compliance to general measures of masking, hand washing and social distancing plays a major role in minimizing disease spread. The Royapettah COVID protocol, though in process of evolution, can be recommended for any health care center with limited resources.

Bacterial and viral vectors as vaccine delivery vehicles for breast cancer therapy.

Breast cancer is the frequently diagnosed cancer among women and it is the most lethal malignancy in women globally. With one million cases every year, breast cancer is the fast-growing cancer type that has a high prevalence rate in young women. The limitations and undesirable side effects of conventional therapies like chemotherapy and radiotherapy on malignant tumors necessitate the development of alternative therapeutic approaches. Gene therapy has emerged as a promising approach to cure a variety of malignant cancer types which involves the delivery of functional gene directly into the target tumor tissue. Efficient gene therapy approach relies on the effective delivery of therapeutic genes to the desired cell type. In this regard, biological and non-biological gene delivery vectors are used to protect the naked foreign DNA to mediate effective tissue entry of the desired gene of interest. In this review, the use of bacterial and viral vectors for breast cancer gene therapy was summarized.

LncRNA OIP5-AS1 is overexpressed in undifferentiated oral tumors and integrated analysis identifies as a downstream effector of stemness-associated transcription factors.

Long non-coding RNAs (lncRNAs) play an important role in the regulation of key cellular processes in early development and cancer. LncRNA Oip5-as1 facilitates stem cell self-renewal in mouse by sponging mmu-miR-7 and modulating NANOG level, yet its role in cancer is less understood. We analyzed OIP5-AS1 expression in oral tumors and in TCGA datasets. We observed overexpression of OIP5-AS1 in oral tumors (P < 0.001) and in tumors of epithelial origin from TCGA. OIP5-AS1 expression was strongly associated with undifferentiated tumors (P = 0.0038). In silico analysis showed miR-7 binding site is conserved in mouse and human OIP5-AS1. However, human NANOG 3'-UTR lost the binding site for hsa-miR-7a-3. Therefore, we screened for other miRNAs that can be sponged by OIP5-AS1 and identified six potential miRNAs and their downstream target genes. Expression analysis showed downregulation of miRNAs and upregulation of downstream target genes, particularly in undifferentiated tumors with high-level of OIP5-AS1 suggesting OIP5-AS1 could post-transcriptionally modulate the downstream target genes. Further, systematic epigenomic analysis of OIP5-AS1 promoter revealed binding motifs for MYC, NANOG and KLF4 suggesting that OIP5-AS1 could be transactivated by stemness-associated transcription factors in cancer. OIP5-AS1 overexpression in undifferentiated oral tumors may be suggestive of enhanced cancer stemness, and consequently, poor clinical outcome.

Dysregulation of miR-200 family microRNAs and epithelial-mesenchymal transition markers in oral squamous cell carcinoma.

MicroRNAs (miRNAs) are reported to function as a major component in the cellular signaling circuit, which regulates epithelial-mesenchymal transition (EMT). Dysregulation of the microRNA-200 (miR-200) family and EMT-associated genes enables tumor metastasis and resistance to therapy. The present study profiled miR-200 family members miR-200a, miR-200b, miR-200c, miR-141 and miR-429, and also several EMT-regulatory genes including zinc finger E-box-binding homeobox (ZEB)1, ZEB2, epithelial cadherin and vimentin in 40 oral primary tumors in order to understand their role(s) in oral squamous cell carcinoma (OSCC). The reverse transcription-quantitative polymerase chain reaction was used to analyze each sample. Results demonstrated a significant downregulation of miR-200 family members in tumors with a history of tobacco chewing/smoking (P<0.0006, P=0.0467, P=0.0014, P=0.0087 and P=0.0230, respectively) and undifferentiated pathology (miR-200a, P=0.0067; miR-200c, P=0.0248). EMT markers ZEB2 (P=0.0451) and vimentin (P=0.0071) were significantly upregulated in the oral tumors. Furthermore, ZEB2 antisense RNA1 was overexpressed in 50% of OSCC samples (P=0.0075). EMT-regulatory genes did not exhibit any association with clinical outcome. The present study also analyzed the expression of EMT-regulatory genes in 523 head and neck squamous cell carcinoma (HNSCC) samples from The Cancer Genome Atlas (TCGA) database, and the association with treatment outcome. Analysis of TCGA datasets also demonstrated no significant association in the expression of EMT markers with disease recurrence and treatment outcome. The results of the present study revealed dysregulation of miR-200 family miRNAs and EMT-regulatory genes in OSCC without any significant effect on treatment outcome.

Long non-coding RNA CCAT1 is overexpressed in oral squamous cell carcinomas and predicts poor prognosis.

Oral squamous cell carcinoma (SCC) is the most common malignant tumor in India with 5-year survival rates totaling <50%. Recently, dysregulation of non-coding RNA was reported as a potential hallmark of carcinogenesis. Colon Cancer Associated Transcript 1 (CCAT1), an lncRNA located in chromosome 8q24, close to the c-Myc gene, has been reported to be overexpressed in many human cancers. In the present study, the authors analyzed the expression of CCAT1, c-Myc and the miRNAs miR155-5p, let7b-5p, miR490-3p and miR218-5p sponged by CCAT1 in 60 oral tumor and 8 normal tissue samples by reverse transcription-quantitative polymerase chain reaction. CCAT1 was significantly overexpressed in 27% (16/60) of oral tumors. Interestingly, a high level of c-Myc expression was observed in all CCAT1 overexpressing cases (P=0.0473). Furthermore, CCAT1 overexpression significantly downregulated miR155-5p (P=0.03) and let7b-5p (P<0.0001). Oral cancer cases expressing high level of CCAT1 (P=0.01) presented poor therapeutic outcome. To the best of the authors' knowledge, this is the first study to report the overexpression of the CCAT1 in oral SCCs, and the results suggested that CCAT1 overexpression may sponge miR155-5p and let7b-5p, and may account for poor treatment response.

Molecular subtypes as a predictor of response to neoadjuvant chemotherapy in breast cancer patients.

PURPOSE: The objective of this study was to assess response to neoadjuvant chemotherapy in molecular subtypes of breast cancer. METHODS: This study included 60 patients with locally advanced and metastatic breast cancer. The authors excluded patients who already underwent mastectomy or were given any chemotherapy/radiotherapy. They analyzed the clinical and immunohistochemical characteristics using core biopsy specimens to determine their correlations with response to chemotherapy. RESULTS: A clinical complete response was observed in 19 patients (31.7%), a clinical partial response in 30 patients (50%), clinical stable disease in 8 patients (13.3%), and progressive disease in 3 patients (5%). A pathologic complete response (pCR) was observed in 7 (21.87%) of 32 patients who underwent surgery. High Ki-67 was associated with human epidermal growth factor receptor 2 (HER2)-positive status (P = 0.027) and triple-negative breast cancer (TNBC) (P = 0.006). Multiple logistic regression analysis showed that pCR was correlated with HER2 status (odds ratio 26.589, confidence interval [CI] =1.606-44.190), P = 0.022. Of the seven patients found to have pCR, six patients (85.7%) were treated with taxol-containing regimen. The other parameters that were correlated with pCR are TNBC and estrogen receptor/progesterone receptor status. Tumor size, Ki-67 value, and grade of the tumor were not correlated with clinical response. CONCLUSION: Molecular subtype in breast cancer is an effective factor for predicting response to neoadjuvant chemotherapy. HER2-positive status was associated with high Ki-67 and high clinical and pathological response rate. Taxol needs to be added in neoadjuvant chemotherapy to improve pCR. Luminal subtypes respond poorly to chemotherapy.

Primary diffuse large B-cell lymphoma of the skull mimicking osteomyelitis.

Primary lymphomas of the skull are extremely rare, as fewer than 20 cases have been reported in the literature. We describe the case of a 51-year-old woman with Huntington chorea who presented with forehead swelling. Imaging studies detected an enhancing mass in the skull with some destruction of the underlying bone. These features were suggestive of osteomyelitis. Surgical excision was performed, and the mass was found to be a primary diffuse large B-cell lymphoma. The patient was administered postoperative chemotherapy, and she was in complete remission at the 1-year follow-up.